1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * alloc.c
5  *
6  * Extent allocs and frees
7  *
8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation; either
13  * version 2 of the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public
21  * License along with this program; if not, write to the
22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23  * Boston, MA 021110-1307, USA.
24  */
25 
26 #include <linux/fs.h>
27 #include <linux/types.h>
28 #include <linux/slab.h>
29 #include <linux/highmem.h>
30 #include <linux/swap.h>
31 #include <linux/quotaops.h>
32 #include <linux/blkdev.h>
33 #include <linux/sched/signal.h>
34 
35 #include <cluster/masklog.h>
36 
37 #include "ocfs2.h"
38 
39 #include "alloc.h"
40 #include "aops.h"
41 #include "blockcheck.h"
42 #include "dlmglue.h"
43 #include "extent_map.h"
44 #include "inode.h"
45 #include "journal.h"
46 #include "localalloc.h"
47 #include "suballoc.h"
48 #include "sysfile.h"
49 #include "file.h"
50 #include "super.h"
51 #include "uptodate.h"
52 #include "xattr.h"
53 #include "refcounttree.h"
54 #include "ocfs2_trace.h"
55 
56 #include "buffer_head_io.h"
57 
58 enum ocfs2_contig_type {
59 	CONTIG_NONE = 0,
60 	CONTIG_LEFT,
61 	CONTIG_RIGHT,
62 	CONTIG_LEFTRIGHT,
63 };
64 
65 static enum ocfs2_contig_type
66 	ocfs2_extent_rec_contig(struct super_block *sb,
67 				struct ocfs2_extent_rec *ext,
68 				struct ocfs2_extent_rec *insert_rec);
69 /*
70  * Operations for a specific extent tree type.
71  *
72  * To implement an on-disk btree (extent tree) type in ocfs2, add
73  * an ocfs2_extent_tree_operations structure and the matching
74  * ocfs2_init_<thingy>_extent_tree() function.  That's pretty much it
75  * for the allocation portion of the extent tree.
76  */
77 struct ocfs2_extent_tree_operations {
78 	/*
79 	 * last_eb_blk is the block number of the right most leaf extent
80 	 * block.  Most on-disk structures containing an extent tree store
81 	 * this value for fast access.  The ->eo_set_last_eb_blk() and
82 	 * ->eo_get_last_eb_blk() operations access this value.  They are
83 	 *  both required.
84 	 */
85 	void (*eo_set_last_eb_blk)(struct ocfs2_extent_tree *et,
86 				   u64 blkno);
87 	u64 (*eo_get_last_eb_blk)(struct ocfs2_extent_tree *et);
88 
89 	/*
90 	 * The on-disk structure usually keeps track of how many total
91 	 * clusters are stored in this extent tree.  This function updates
92 	 * that value.  new_clusters is the delta, and must be
93 	 * added to the total.  Required.
94 	 */
95 	void (*eo_update_clusters)(struct ocfs2_extent_tree *et,
96 				   u32 new_clusters);
97 
98 	/*
99 	 * If this extent tree is supported by an extent map, insert
100 	 * a record into the map.
101 	 */
102 	void (*eo_extent_map_insert)(struct ocfs2_extent_tree *et,
103 				     struct ocfs2_extent_rec *rec);
104 
105 	/*
106 	 * If this extent tree is supported by an extent map, truncate the
107 	 * map to clusters,
108 	 */
109 	void (*eo_extent_map_truncate)(struct ocfs2_extent_tree *et,
110 				       u32 clusters);
111 
112 	/*
113 	 * If ->eo_insert_check() exists, it is called before rec is
114 	 * inserted into the extent tree.  It is optional.
115 	 */
116 	int (*eo_insert_check)(struct ocfs2_extent_tree *et,
117 			       struct ocfs2_extent_rec *rec);
118 	int (*eo_sanity_check)(struct ocfs2_extent_tree *et);
119 
120 	/*
121 	 * --------------------------------------------------------------
122 	 * The remaining are internal to ocfs2_extent_tree and don't have
123 	 * accessor functions
124 	 */
125 
126 	/*
127 	 * ->eo_fill_root_el() takes et->et_object and sets et->et_root_el.
128 	 * It is required.
129 	 */
130 	void (*eo_fill_root_el)(struct ocfs2_extent_tree *et);
131 
132 	/*
133 	 * ->eo_fill_max_leaf_clusters sets et->et_max_leaf_clusters if
134 	 * it exists.  If it does not, et->et_max_leaf_clusters is set
135 	 * to 0 (unlimited).  Optional.
136 	 */
137 	void (*eo_fill_max_leaf_clusters)(struct ocfs2_extent_tree *et);
138 
139 	/*
140 	 * ->eo_extent_contig test whether the 2 ocfs2_extent_rec
141 	 * are contiguous or not. Optional. Don't need to set it if use
142 	 * ocfs2_extent_rec as the tree leaf.
143 	 */
144 	enum ocfs2_contig_type
145 		(*eo_extent_contig)(struct ocfs2_extent_tree *et,
146 				    struct ocfs2_extent_rec *ext,
147 				    struct ocfs2_extent_rec *insert_rec);
148 };
149 
150 
151 /*
152  * Pre-declare ocfs2_dinode_et_ops so we can use it as a sanity check
153  * in the methods.
154  */
155 static u64 ocfs2_dinode_get_last_eb_blk(struct ocfs2_extent_tree *et);
156 static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
157 					 u64 blkno);
158 static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
159 					 u32 clusters);
160 static void ocfs2_dinode_extent_map_insert(struct ocfs2_extent_tree *et,
161 					   struct ocfs2_extent_rec *rec);
162 static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
163 					     u32 clusters);
164 static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
165 				     struct ocfs2_extent_rec *rec);
166 static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et);
167 static void ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree *et);
168 
169 static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
170 					struct ocfs2_extent_tree *et,
171 					struct buffer_head **new_eb_bh,
172 					int blk_wanted, int *blk_given);
173 static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et);
174 
175 static const struct ocfs2_extent_tree_operations ocfs2_dinode_et_ops = {
176 	.eo_set_last_eb_blk	= ocfs2_dinode_set_last_eb_blk,
177 	.eo_get_last_eb_blk	= ocfs2_dinode_get_last_eb_blk,
178 	.eo_update_clusters	= ocfs2_dinode_update_clusters,
179 	.eo_extent_map_insert	= ocfs2_dinode_extent_map_insert,
180 	.eo_extent_map_truncate	= ocfs2_dinode_extent_map_truncate,
181 	.eo_insert_check	= ocfs2_dinode_insert_check,
182 	.eo_sanity_check	= ocfs2_dinode_sanity_check,
183 	.eo_fill_root_el	= ocfs2_dinode_fill_root_el,
184 };
185 
ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 blkno)186 static void ocfs2_dinode_set_last_eb_blk(struct ocfs2_extent_tree *et,
187 					 u64 blkno)
188 {
189 	struct ocfs2_dinode *di = et->et_object;
190 
191 	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
192 	di->i_last_eb_blk = cpu_to_le64(blkno);
193 }
194 
ocfs2_dinode_get_last_eb_blk(struct ocfs2_extent_tree * et)195 static u64 ocfs2_dinode_get_last_eb_blk(struct ocfs2_extent_tree *et)
196 {
197 	struct ocfs2_dinode *di = et->et_object;
198 
199 	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
200 	return le64_to_cpu(di->i_last_eb_blk);
201 }
202 
ocfs2_dinode_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)203 static void ocfs2_dinode_update_clusters(struct ocfs2_extent_tree *et,
204 					 u32 clusters)
205 {
206 	struct ocfs2_inode_info *oi = cache_info_to_inode(et->et_ci);
207 	struct ocfs2_dinode *di = et->et_object;
208 
209 	le32_add_cpu(&di->i_clusters, clusters);
210 	spin_lock(&oi->ip_lock);
211 	oi->ip_clusters = le32_to_cpu(di->i_clusters);
212 	spin_unlock(&oi->ip_lock);
213 }
214 
ocfs2_dinode_extent_map_insert(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * rec)215 static void ocfs2_dinode_extent_map_insert(struct ocfs2_extent_tree *et,
216 					   struct ocfs2_extent_rec *rec)
217 {
218 	struct inode *inode = &cache_info_to_inode(et->et_ci)->vfs_inode;
219 
220 	ocfs2_extent_map_insert_rec(inode, rec);
221 }
222 
ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree * et,u32 clusters)223 static void ocfs2_dinode_extent_map_truncate(struct ocfs2_extent_tree *et,
224 					     u32 clusters)
225 {
226 	struct inode *inode = &cache_info_to_inode(et->et_ci)->vfs_inode;
227 
228 	ocfs2_extent_map_trunc(inode, clusters);
229 }
230 
ocfs2_dinode_insert_check(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * rec)231 static int ocfs2_dinode_insert_check(struct ocfs2_extent_tree *et,
232 				     struct ocfs2_extent_rec *rec)
233 {
234 	struct ocfs2_inode_info *oi = cache_info_to_inode(et->et_ci);
235 	struct ocfs2_super *osb = OCFS2_SB(oi->vfs_inode.i_sb);
236 
237 	BUG_ON(oi->ip_dyn_features & OCFS2_INLINE_DATA_FL);
238 	mlog_bug_on_msg(!ocfs2_sparse_alloc(osb) &&
239 			(oi->ip_clusters != le32_to_cpu(rec->e_cpos)),
240 			"Device %s, asking for sparse allocation: inode %llu, "
241 			"cpos %u, clusters %u\n",
242 			osb->dev_str,
243 			(unsigned long long)oi->ip_blkno,
244 			rec->e_cpos, oi->ip_clusters);
245 
246 	return 0;
247 }
248 
ocfs2_dinode_sanity_check(struct ocfs2_extent_tree * et)249 static int ocfs2_dinode_sanity_check(struct ocfs2_extent_tree *et)
250 {
251 	struct ocfs2_dinode *di = et->et_object;
252 
253 	BUG_ON(et->et_ops != &ocfs2_dinode_et_ops);
254 	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
255 
256 	return 0;
257 }
258 
ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree * et)259 static void ocfs2_dinode_fill_root_el(struct ocfs2_extent_tree *et)
260 {
261 	struct ocfs2_dinode *di = et->et_object;
262 
263 	et->et_root_el = &di->id2.i_list;
264 }
265 
266 
ocfs2_xattr_value_fill_root_el(struct ocfs2_extent_tree * et)267 static void ocfs2_xattr_value_fill_root_el(struct ocfs2_extent_tree *et)
268 {
269 	struct ocfs2_xattr_value_buf *vb = et->et_object;
270 
271 	et->et_root_el = &vb->vb_xv->xr_list;
272 }
273 
ocfs2_xattr_value_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 blkno)274 static void ocfs2_xattr_value_set_last_eb_blk(struct ocfs2_extent_tree *et,
275 					      u64 blkno)
276 {
277 	struct ocfs2_xattr_value_buf *vb = et->et_object;
278 
279 	vb->vb_xv->xr_last_eb_blk = cpu_to_le64(blkno);
280 }
281 
ocfs2_xattr_value_get_last_eb_blk(struct ocfs2_extent_tree * et)282 static u64 ocfs2_xattr_value_get_last_eb_blk(struct ocfs2_extent_tree *et)
283 {
284 	struct ocfs2_xattr_value_buf *vb = et->et_object;
285 
286 	return le64_to_cpu(vb->vb_xv->xr_last_eb_blk);
287 }
288 
ocfs2_xattr_value_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)289 static void ocfs2_xattr_value_update_clusters(struct ocfs2_extent_tree *et,
290 					      u32 clusters)
291 {
292 	struct ocfs2_xattr_value_buf *vb = et->et_object;
293 
294 	le32_add_cpu(&vb->vb_xv->xr_clusters, clusters);
295 }
296 
297 static const struct ocfs2_extent_tree_operations ocfs2_xattr_value_et_ops = {
298 	.eo_set_last_eb_blk	= ocfs2_xattr_value_set_last_eb_blk,
299 	.eo_get_last_eb_blk	= ocfs2_xattr_value_get_last_eb_blk,
300 	.eo_update_clusters	= ocfs2_xattr_value_update_clusters,
301 	.eo_fill_root_el	= ocfs2_xattr_value_fill_root_el,
302 };
303 
ocfs2_xattr_tree_fill_root_el(struct ocfs2_extent_tree * et)304 static void ocfs2_xattr_tree_fill_root_el(struct ocfs2_extent_tree *et)
305 {
306 	struct ocfs2_xattr_block *xb = et->et_object;
307 
308 	et->et_root_el = &xb->xb_attrs.xb_root.xt_list;
309 }
310 
ocfs2_xattr_tree_fill_max_leaf_clusters(struct ocfs2_extent_tree * et)311 static void ocfs2_xattr_tree_fill_max_leaf_clusters(struct ocfs2_extent_tree *et)
312 {
313 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
314 	et->et_max_leaf_clusters =
315 		ocfs2_clusters_for_bytes(sb, OCFS2_MAX_XATTR_TREE_LEAF_SIZE);
316 }
317 
ocfs2_xattr_tree_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 blkno)318 static void ocfs2_xattr_tree_set_last_eb_blk(struct ocfs2_extent_tree *et,
319 					     u64 blkno)
320 {
321 	struct ocfs2_xattr_block *xb = et->et_object;
322 	struct ocfs2_xattr_tree_root *xt = &xb->xb_attrs.xb_root;
323 
324 	xt->xt_last_eb_blk = cpu_to_le64(blkno);
325 }
326 
ocfs2_xattr_tree_get_last_eb_blk(struct ocfs2_extent_tree * et)327 static u64 ocfs2_xattr_tree_get_last_eb_blk(struct ocfs2_extent_tree *et)
328 {
329 	struct ocfs2_xattr_block *xb = et->et_object;
330 	struct ocfs2_xattr_tree_root *xt = &xb->xb_attrs.xb_root;
331 
332 	return le64_to_cpu(xt->xt_last_eb_blk);
333 }
334 
ocfs2_xattr_tree_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)335 static void ocfs2_xattr_tree_update_clusters(struct ocfs2_extent_tree *et,
336 					     u32 clusters)
337 {
338 	struct ocfs2_xattr_block *xb = et->et_object;
339 
340 	le32_add_cpu(&xb->xb_attrs.xb_root.xt_clusters, clusters);
341 }
342 
343 static const struct ocfs2_extent_tree_operations ocfs2_xattr_tree_et_ops = {
344 	.eo_set_last_eb_blk	= ocfs2_xattr_tree_set_last_eb_blk,
345 	.eo_get_last_eb_blk	= ocfs2_xattr_tree_get_last_eb_blk,
346 	.eo_update_clusters	= ocfs2_xattr_tree_update_clusters,
347 	.eo_fill_root_el	= ocfs2_xattr_tree_fill_root_el,
348 	.eo_fill_max_leaf_clusters = ocfs2_xattr_tree_fill_max_leaf_clusters,
349 };
350 
ocfs2_dx_root_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 blkno)351 static void ocfs2_dx_root_set_last_eb_blk(struct ocfs2_extent_tree *et,
352 					  u64 blkno)
353 {
354 	struct ocfs2_dx_root_block *dx_root = et->et_object;
355 
356 	dx_root->dr_last_eb_blk = cpu_to_le64(blkno);
357 }
358 
ocfs2_dx_root_get_last_eb_blk(struct ocfs2_extent_tree * et)359 static u64 ocfs2_dx_root_get_last_eb_blk(struct ocfs2_extent_tree *et)
360 {
361 	struct ocfs2_dx_root_block *dx_root = et->et_object;
362 
363 	return le64_to_cpu(dx_root->dr_last_eb_blk);
364 }
365 
ocfs2_dx_root_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)366 static void ocfs2_dx_root_update_clusters(struct ocfs2_extent_tree *et,
367 					  u32 clusters)
368 {
369 	struct ocfs2_dx_root_block *dx_root = et->et_object;
370 
371 	le32_add_cpu(&dx_root->dr_clusters, clusters);
372 }
373 
ocfs2_dx_root_sanity_check(struct ocfs2_extent_tree * et)374 static int ocfs2_dx_root_sanity_check(struct ocfs2_extent_tree *et)
375 {
376 	struct ocfs2_dx_root_block *dx_root = et->et_object;
377 
378 	BUG_ON(!OCFS2_IS_VALID_DX_ROOT(dx_root));
379 
380 	return 0;
381 }
382 
ocfs2_dx_root_fill_root_el(struct ocfs2_extent_tree * et)383 static void ocfs2_dx_root_fill_root_el(struct ocfs2_extent_tree *et)
384 {
385 	struct ocfs2_dx_root_block *dx_root = et->et_object;
386 
387 	et->et_root_el = &dx_root->dr_list;
388 }
389 
390 static const struct ocfs2_extent_tree_operations ocfs2_dx_root_et_ops = {
391 	.eo_set_last_eb_blk	= ocfs2_dx_root_set_last_eb_blk,
392 	.eo_get_last_eb_blk	= ocfs2_dx_root_get_last_eb_blk,
393 	.eo_update_clusters	= ocfs2_dx_root_update_clusters,
394 	.eo_sanity_check	= ocfs2_dx_root_sanity_check,
395 	.eo_fill_root_el	= ocfs2_dx_root_fill_root_el,
396 };
397 
ocfs2_refcount_tree_fill_root_el(struct ocfs2_extent_tree * et)398 static void ocfs2_refcount_tree_fill_root_el(struct ocfs2_extent_tree *et)
399 {
400 	struct ocfs2_refcount_block *rb = et->et_object;
401 
402 	et->et_root_el = &rb->rf_list;
403 }
404 
ocfs2_refcount_tree_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 blkno)405 static void ocfs2_refcount_tree_set_last_eb_blk(struct ocfs2_extent_tree *et,
406 						u64 blkno)
407 {
408 	struct ocfs2_refcount_block *rb = et->et_object;
409 
410 	rb->rf_last_eb_blk = cpu_to_le64(blkno);
411 }
412 
ocfs2_refcount_tree_get_last_eb_blk(struct ocfs2_extent_tree * et)413 static u64 ocfs2_refcount_tree_get_last_eb_blk(struct ocfs2_extent_tree *et)
414 {
415 	struct ocfs2_refcount_block *rb = et->et_object;
416 
417 	return le64_to_cpu(rb->rf_last_eb_blk);
418 }
419 
ocfs2_refcount_tree_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)420 static void ocfs2_refcount_tree_update_clusters(struct ocfs2_extent_tree *et,
421 						u32 clusters)
422 {
423 	struct ocfs2_refcount_block *rb = et->et_object;
424 
425 	le32_add_cpu(&rb->rf_clusters, clusters);
426 }
427 
428 static enum ocfs2_contig_type
ocfs2_refcount_tree_extent_contig(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * ext,struct ocfs2_extent_rec * insert_rec)429 ocfs2_refcount_tree_extent_contig(struct ocfs2_extent_tree *et,
430 				  struct ocfs2_extent_rec *ext,
431 				  struct ocfs2_extent_rec *insert_rec)
432 {
433 	return CONTIG_NONE;
434 }
435 
436 static const struct ocfs2_extent_tree_operations ocfs2_refcount_tree_et_ops = {
437 	.eo_set_last_eb_blk	= ocfs2_refcount_tree_set_last_eb_blk,
438 	.eo_get_last_eb_blk	= ocfs2_refcount_tree_get_last_eb_blk,
439 	.eo_update_clusters	= ocfs2_refcount_tree_update_clusters,
440 	.eo_fill_root_el	= ocfs2_refcount_tree_fill_root_el,
441 	.eo_extent_contig	= ocfs2_refcount_tree_extent_contig,
442 };
443 
__ocfs2_init_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct buffer_head * bh,ocfs2_journal_access_func access,void * obj,const struct ocfs2_extent_tree_operations * ops)444 static void __ocfs2_init_extent_tree(struct ocfs2_extent_tree *et,
445 				     struct ocfs2_caching_info *ci,
446 				     struct buffer_head *bh,
447 				     ocfs2_journal_access_func access,
448 				     void *obj,
449 				     const struct ocfs2_extent_tree_operations *ops)
450 {
451 	et->et_ops = ops;
452 	et->et_root_bh = bh;
453 	et->et_ci = ci;
454 	et->et_root_journal_access = access;
455 	if (!obj)
456 		obj = (void *)bh->b_data;
457 	et->et_object = obj;
458 	et->et_dealloc = NULL;
459 
460 	et->et_ops->eo_fill_root_el(et);
461 	if (!et->et_ops->eo_fill_max_leaf_clusters)
462 		et->et_max_leaf_clusters = 0;
463 	else
464 		et->et_ops->eo_fill_max_leaf_clusters(et);
465 }
466 
ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct buffer_head * bh)467 void ocfs2_init_dinode_extent_tree(struct ocfs2_extent_tree *et,
468 				   struct ocfs2_caching_info *ci,
469 				   struct buffer_head *bh)
470 {
471 	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_di,
472 				 NULL, &ocfs2_dinode_et_ops);
473 }
474 
ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct buffer_head * bh)475 void ocfs2_init_xattr_tree_extent_tree(struct ocfs2_extent_tree *et,
476 				       struct ocfs2_caching_info *ci,
477 				       struct buffer_head *bh)
478 {
479 	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_xb,
480 				 NULL, &ocfs2_xattr_tree_et_ops);
481 }
482 
ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct ocfs2_xattr_value_buf * vb)483 void ocfs2_init_xattr_value_extent_tree(struct ocfs2_extent_tree *et,
484 					struct ocfs2_caching_info *ci,
485 					struct ocfs2_xattr_value_buf *vb)
486 {
487 	__ocfs2_init_extent_tree(et, ci, vb->vb_bh, vb->vb_access, vb,
488 				 &ocfs2_xattr_value_et_ops);
489 }
490 
ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct buffer_head * bh)491 void ocfs2_init_dx_root_extent_tree(struct ocfs2_extent_tree *et,
492 				    struct ocfs2_caching_info *ci,
493 				    struct buffer_head *bh)
494 {
495 	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_dr,
496 				 NULL, &ocfs2_dx_root_et_ops);
497 }
498 
ocfs2_init_refcount_extent_tree(struct ocfs2_extent_tree * et,struct ocfs2_caching_info * ci,struct buffer_head * bh)499 void ocfs2_init_refcount_extent_tree(struct ocfs2_extent_tree *et,
500 				     struct ocfs2_caching_info *ci,
501 				     struct buffer_head *bh)
502 {
503 	__ocfs2_init_extent_tree(et, ci, bh, ocfs2_journal_access_rb,
504 				 NULL, &ocfs2_refcount_tree_et_ops);
505 }
506 
ocfs2_et_set_last_eb_blk(struct ocfs2_extent_tree * et,u64 new_last_eb_blk)507 static inline void ocfs2_et_set_last_eb_blk(struct ocfs2_extent_tree *et,
508 					    u64 new_last_eb_blk)
509 {
510 	et->et_ops->eo_set_last_eb_blk(et, new_last_eb_blk);
511 }
512 
ocfs2_et_get_last_eb_blk(struct ocfs2_extent_tree * et)513 static inline u64 ocfs2_et_get_last_eb_blk(struct ocfs2_extent_tree *et)
514 {
515 	return et->et_ops->eo_get_last_eb_blk(et);
516 }
517 
ocfs2_et_update_clusters(struct ocfs2_extent_tree * et,u32 clusters)518 static inline void ocfs2_et_update_clusters(struct ocfs2_extent_tree *et,
519 					    u32 clusters)
520 {
521 	et->et_ops->eo_update_clusters(et, clusters);
522 }
523 
ocfs2_et_extent_map_insert(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * rec)524 static inline void ocfs2_et_extent_map_insert(struct ocfs2_extent_tree *et,
525 					      struct ocfs2_extent_rec *rec)
526 {
527 	if (et->et_ops->eo_extent_map_insert)
528 		et->et_ops->eo_extent_map_insert(et, rec);
529 }
530 
ocfs2_et_extent_map_truncate(struct ocfs2_extent_tree * et,u32 clusters)531 static inline void ocfs2_et_extent_map_truncate(struct ocfs2_extent_tree *et,
532 						u32 clusters)
533 {
534 	if (et->et_ops->eo_extent_map_truncate)
535 		et->et_ops->eo_extent_map_truncate(et, clusters);
536 }
537 
ocfs2_et_root_journal_access(handle_t * handle,struct ocfs2_extent_tree * et,int type)538 static inline int ocfs2_et_root_journal_access(handle_t *handle,
539 					       struct ocfs2_extent_tree *et,
540 					       int type)
541 {
542 	return et->et_root_journal_access(handle, et->et_ci, et->et_root_bh,
543 					  type);
544 }
545 
546 static inline enum ocfs2_contig_type
ocfs2_et_extent_contig(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * rec,struct ocfs2_extent_rec * insert_rec)547 	ocfs2_et_extent_contig(struct ocfs2_extent_tree *et,
548 			       struct ocfs2_extent_rec *rec,
549 			       struct ocfs2_extent_rec *insert_rec)
550 {
551 	if (et->et_ops->eo_extent_contig)
552 		return et->et_ops->eo_extent_contig(et, rec, insert_rec);
553 
554 	return ocfs2_extent_rec_contig(
555 				ocfs2_metadata_cache_get_super(et->et_ci),
556 				rec, insert_rec);
557 }
558 
ocfs2_et_insert_check(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * rec)559 static inline int ocfs2_et_insert_check(struct ocfs2_extent_tree *et,
560 					struct ocfs2_extent_rec *rec)
561 {
562 	int ret = 0;
563 
564 	if (et->et_ops->eo_insert_check)
565 		ret = et->et_ops->eo_insert_check(et, rec);
566 	return ret;
567 }
568 
ocfs2_et_sanity_check(struct ocfs2_extent_tree * et)569 static inline int ocfs2_et_sanity_check(struct ocfs2_extent_tree *et)
570 {
571 	int ret = 0;
572 
573 	if (et->et_ops->eo_sanity_check)
574 		ret = et->et_ops->eo_sanity_check(et);
575 	return ret;
576 }
577 
578 static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
579 					 struct ocfs2_extent_block *eb);
580 static void ocfs2_adjust_rightmost_records(handle_t *handle,
581 					   struct ocfs2_extent_tree *et,
582 					   struct ocfs2_path *path,
583 					   struct ocfs2_extent_rec *insert_rec);
584 /*
585  * Reset the actual path elements so that we can re-use the structure
586  * to build another path. Generally, this involves freeing the buffer
587  * heads.
588  */
ocfs2_reinit_path(struct ocfs2_path * path,int keep_root)589 void ocfs2_reinit_path(struct ocfs2_path *path, int keep_root)
590 {
591 	int i, start = 0, depth = 0;
592 	struct ocfs2_path_item *node;
593 
594 	if (keep_root)
595 		start = 1;
596 
597 	for(i = start; i < path_num_items(path); i++) {
598 		node = &path->p_node[i];
599 
600 		brelse(node->bh);
601 		node->bh = NULL;
602 		node->el = NULL;
603 	}
604 
605 	/*
606 	 * Tree depth may change during truncate, or insert. If we're
607 	 * keeping the root extent list, then make sure that our path
608 	 * structure reflects the proper depth.
609 	 */
610 	if (keep_root)
611 		depth = le16_to_cpu(path_root_el(path)->l_tree_depth);
612 	else
613 		path_root_access(path) = NULL;
614 
615 	path->p_tree_depth = depth;
616 }
617 
ocfs2_free_path(struct ocfs2_path * path)618 void ocfs2_free_path(struct ocfs2_path *path)
619 {
620 	if (path) {
621 		ocfs2_reinit_path(path, 0);
622 		kfree(path);
623 	}
624 }
625 
626 /*
627  * All the elements of src into dest. After this call, src could be freed
628  * without affecting dest.
629  *
630  * Both paths should have the same root. Any non-root elements of dest
631  * will be freed.
632  */
ocfs2_cp_path(struct ocfs2_path * dest,struct ocfs2_path * src)633 static void ocfs2_cp_path(struct ocfs2_path *dest, struct ocfs2_path *src)
634 {
635 	int i;
636 
637 	BUG_ON(path_root_bh(dest) != path_root_bh(src));
638 	BUG_ON(path_root_el(dest) != path_root_el(src));
639 	BUG_ON(path_root_access(dest) != path_root_access(src));
640 
641 	ocfs2_reinit_path(dest, 1);
642 
643 	for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
644 		dest->p_node[i].bh = src->p_node[i].bh;
645 		dest->p_node[i].el = src->p_node[i].el;
646 
647 		if (dest->p_node[i].bh)
648 			get_bh(dest->p_node[i].bh);
649 	}
650 }
651 
652 /*
653  * Make the *dest path the same as src and re-initialize src path to
654  * have a root only.
655  */
ocfs2_mv_path(struct ocfs2_path * dest,struct ocfs2_path * src)656 static void ocfs2_mv_path(struct ocfs2_path *dest, struct ocfs2_path *src)
657 {
658 	int i;
659 
660 	BUG_ON(path_root_bh(dest) != path_root_bh(src));
661 	BUG_ON(path_root_access(dest) != path_root_access(src));
662 
663 	for(i = 1; i < OCFS2_MAX_PATH_DEPTH; i++) {
664 		brelse(dest->p_node[i].bh);
665 
666 		dest->p_node[i].bh = src->p_node[i].bh;
667 		dest->p_node[i].el = src->p_node[i].el;
668 
669 		src->p_node[i].bh = NULL;
670 		src->p_node[i].el = NULL;
671 	}
672 }
673 
674 /*
675  * Insert an extent block at given index.
676  *
677  * This will not take an additional reference on eb_bh.
678  */
ocfs2_path_insert_eb(struct ocfs2_path * path,int index,struct buffer_head * eb_bh)679 static inline void ocfs2_path_insert_eb(struct ocfs2_path *path, int index,
680 					struct buffer_head *eb_bh)
681 {
682 	struct ocfs2_extent_block *eb = (struct ocfs2_extent_block *)eb_bh->b_data;
683 
684 	/*
685 	 * Right now, no root bh is an extent block, so this helps
686 	 * catch code errors with dinode trees. The assertion can be
687 	 * safely removed if we ever need to insert extent block
688 	 * structures at the root.
689 	 */
690 	BUG_ON(index == 0);
691 
692 	path->p_node[index].bh = eb_bh;
693 	path->p_node[index].el = &eb->h_list;
694 }
695 
ocfs2_new_path(struct buffer_head * root_bh,struct ocfs2_extent_list * root_el,ocfs2_journal_access_func access)696 static struct ocfs2_path *ocfs2_new_path(struct buffer_head *root_bh,
697 					 struct ocfs2_extent_list *root_el,
698 					 ocfs2_journal_access_func access)
699 {
700 	struct ocfs2_path *path;
701 
702 	BUG_ON(le16_to_cpu(root_el->l_tree_depth) >= OCFS2_MAX_PATH_DEPTH);
703 
704 	path = kzalloc(sizeof(*path), GFP_NOFS);
705 	if (path) {
706 		path->p_tree_depth = le16_to_cpu(root_el->l_tree_depth);
707 		get_bh(root_bh);
708 		path_root_bh(path) = root_bh;
709 		path_root_el(path) = root_el;
710 		path_root_access(path) = access;
711 	}
712 
713 	return path;
714 }
715 
ocfs2_new_path_from_path(struct ocfs2_path * path)716 struct ocfs2_path *ocfs2_new_path_from_path(struct ocfs2_path *path)
717 {
718 	return ocfs2_new_path(path_root_bh(path), path_root_el(path),
719 			      path_root_access(path));
720 }
721 
ocfs2_new_path_from_et(struct ocfs2_extent_tree * et)722 struct ocfs2_path *ocfs2_new_path_from_et(struct ocfs2_extent_tree *et)
723 {
724 	return ocfs2_new_path(et->et_root_bh, et->et_root_el,
725 			      et->et_root_journal_access);
726 }
727 
728 /*
729  * Journal the buffer at depth idx.  All idx>0 are extent_blocks,
730  * otherwise it's the root_access function.
731  *
732  * I don't like the way this function's name looks next to
733  * ocfs2_journal_access_path(), but I don't have a better one.
734  */
ocfs2_path_bh_journal_access(handle_t * handle,struct ocfs2_caching_info * ci,struct ocfs2_path * path,int idx)735 int ocfs2_path_bh_journal_access(handle_t *handle,
736 				 struct ocfs2_caching_info *ci,
737 				 struct ocfs2_path *path,
738 				 int idx)
739 {
740 	ocfs2_journal_access_func access = path_root_access(path);
741 
742 	if (!access)
743 		access = ocfs2_journal_access;
744 
745 	if (idx)
746 		access = ocfs2_journal_access_eb;
747 
748 	return access(handle, ci, path->p_node[idx].bh,
749 		      OCFS2_JOURNAL_ACCESS_WRITE);
750 }
751 
752 /*
753  * Convenience function to journal all components in a path.
754  */
ocfs2_journal_access_path(struct ocfs2_caching_info * ci,handle_t * handle,struct ocfs2_path * path)755 int ocfs2_journal_access_path(struct ocfs2_caching_info *ci,
756 			      handle_t *handle,
757 			      struct ocfs2_path *path)
758 {
759 	int i, ret = 0;
760 
761 	if (!path)
762 		goto out;
763 
764 	for(i = 0; i < path_num_items(path); i++) {
765 		ret = ocfs2_path_bh_journal_access(handle, ci, path, i);
766 		if (ret < 0) {
767 			mlog_errno(ret);
768 			goto out;
769 		}
770 	}
771 
772 out:
773 	return ret;
774 }
775 
776 /*
777  * Return the index of the extent record which contains cluster #v_cluster.
778  * -1 is returned if it was not found.
779  *
780  * Should work fine on interior and exterior nodes.
781  */
ocfs2_search_extent_list(struct ocfs2_extent_list * el,u32 v_cluster)782 int ocfs2_search_extent_list(struct ocfs2_extent_list *el, u32 v_cluster)
783 {
784 	int ret = -1;
785 	int i;
786 	struct ocfs2_extent_rec *rec;
787 	u32 rec_end, rec_start, clusters;
788 
789 	for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
790 		rec = &el->l_recs[i];
791 
792 		rec_start = le32_to_cpu(rec->e_cpos);
793 		clusters = ocfs2_rec_clusters(el, rec);
794 
795 		rec_end = rec_start + clusters;
796 
797 		if (v_cluster >= rec_start && v_cluster < rec_end) {
798 			ret = i;
799 			break;
800 		}
801 	}
802 
803 	return ret;
804 }
805 
806 /*
807  * NOTE: ocfs2_block_extent_contig(), ocfs2_extents_adjacent() and
808  * ocfs2_extent_rec_contig only work properly against leaf nodes!
809  */
ocfs2_block_extent_contig(struct super_block * sb,struct ocfs2_extent_rec * ext,u64 blkno)810 static int ocfs2_block_extent_contig(struct super_block *sb,
811 				     struct ocfs2_extent_rec *ext,
812 				     u64 blkno)
813 {
814 	u64 blk_end = le64_to_cpu(ext->e_blkno);
815 
816 	blk_end += ocfs2_clusters_to_blocks(sb,
817 				    le16_to_cpu(ext->e_leaf_clusters));
818 
819 	return blkno == blk_end;
820 }
821 
ocfs2_extents_adjacent(struct ocfs2_extent_rec * left,struct ocfs2_extent_rec * right)822 static int ocfs2_extents_adjacent(struct ocfs2_extent_rec *left,
823 				  struct ocfs2_extent_rec *right)
824 {
825 	u32 left_range;
826 
827 	left_range = le32_to_cpu(left->e_cpos) +
828 		le16_to_cpu(left->e_leaf_clusters);
829 
830 	return (left_range == le32_to_cpu(right->e_cpos));
831 }
832 
833 static enum ocfs2_contig_type
ocfs2_extent_rec_contig(struct super_block * sb,struct ocfs2_extent_rec * ext,struct ocfs2_extent_rec * insert_rec)834 	ocfs2_extent_rec_contig(struct super_block *sb,
835 				struct ocfs2_extent_rec *ext,
836 				struct ocfs2_extent_rec *insert_rec)
837 {
838 	u64 blkno = le64_to_cpu(insert_rec->e_blkno);
839 
840 	/*
841 	 * Refuse to coalesce extent records with different flag
842 	 * fields - we don't want to mix unwritten extents with user
843 	 * data.
844 	 */
845 	if (ext->e_flags != insert_rec->e_flags)
846 		return CONTIG_NONE;
847 
848 	if (ocfs2_extents_adjacent(ext, insert_rec) &&
849 	    ocfs2_block_extent_contig(sb, ext, blkno))
850 			return CONTIG_RIGHT;
851 
852 	blkno = le64_to_cpu(ext->e_blkno);
853 	if (ocfs2_extents_adjacent(insert_rec, ext) &&
854 	    ocfs2_block_extent_contig(sb, insert_rec, blkno))
855 		return CONTIG_LEFT;
856 
857 	return CONTIG_NONE;
858 }
859 
860 /*
861  * NOTE: We can have pretty much any combination of contiguousness and
862  * appending.
863  *
864  * The usefulness of APPEND_TAIL is more in that it lets us know that
865  * we'll have to update the path to that leaf.
866  */
867 enum ocfs2_append_type {
868 	APPEND_NONE = 0,
869 	APPEND_TAIL,
870 };
871 
872 enum ocfs2_split_type {
873 	SPLIT_NONE = 0,
874 	SPLIT_LEFT,
875 	SPLIT_RIGHT,
876 };
877 
878 struct ocfs2_insert_type {
879 	enum ocfs2_split_type	ins_split;
880 	enum ocfs2_append_type	ins_appending;
881 	enum ocfs2_contig_type	ins_contig;
882 	int			ins_contig_index;
883 	int			ins_tree_depth;
884 };
885 
886 struct ocfs2_merge_ctxt {
887 	enum ocfs2_contig_type	c_contig_type;
888 	int			c_has_empty_extent;
889 	int			c_split_covers_rec;
890 };
891 
ocfs2_validate_extent_block(struct super_block * sb,struct buffer_head * bh)892 static int ocfs2_validate_extent_block(struct super_block *sb,
893 				       struct buffer_head *bh)
894 {
895 	int rc;
896 	struct ocfs2_extent_block *eb =
897 		(struct ocfs2_extent_block *)bh->b_data;
898 
899 	trace_ocfs2_validate_extent_block((unsigned long long)bh->b_blocknr);
900 
901 	BUG_ON(!buffer_uptodate(bh));
902 
903 	/*
904 	 * If the ecc fails, we return the error but otherwise
905 	 * leave the filesystem running.  We know any error is
906 	 * local to this block.
907 	 */
908 	rc = ocfs2_validate_meta_ecc(sb, bh->b_data, &eb->h_check);
909 	if (rc) {
910 		mlog(ML_ERROR, "Checksum failed for extent block %llu\n",
911 		     (unsigned long long)bh->b_blocknr);
912 		return rc;
913 	}
914 
915 	/*
916 	 * Errors after here are fatal.
917 	 */
918 
919 	if (!OCFS2_IS_VALID_EXTENT_BLOCK(eb)) {
920 		rc = ocfs2_error(sb,
921 				 "Extent block #%llu has bad signature %.*s\n",
922 				 (unsigned long long)bh->b_blocknr, 7,
923 				 eb->h_signature);
924 		goto bail;
925 	}
926 
927 	if (le64_to_cpu(eb->h_blkno) != bh->b_blocknr) {
928 		rc = ocfs2_error(sb,
929 				 "Extent block #%llu has an invalid h_blkno of %llu\n",
930 				 (unsigned long long)bh->b_blocknr,
931 				 (unsigned long long)le64_to_cpu(eb->h_blkno));
932 		goto bail;
933 	}
934 
935 	if (le32_to_cpu(eb->h_fs_generation) != OCFS2_SB(sb)->fs_generation)
936 		rc = ocfs2_error(sb,
937 				 "Extent block #%llu has an invalid h_fs_generation of #%u\n",
938 				 (unsigned long long)bh->b_blocknr,
939 				 le32_to_cpu(eb->h_fs_generation));
940 bail:
941 	return rc;
942 }
943 
ocfs2_read_extent_block(struct ocfs2_caching_info * ci,u64 eb_blkno,struct buffer_head ** bh)944 int ocfs2_read_extent_block(struct ocfs2_caching_info *ci, u64 eb_blkno,
945 			    struct buffer_head **bh)
946 {
947 	int rc;
948 	struct buffer_head *tmp = *bh;
949 
950 	rc = ocfs2_read_block(ci, eb_blkno, &tmp,
951 			      ocfs2_validate_extent_block);
952 
953 	/* If ocfs2_read_block() got us a new bh, pass it up. */
954 	if (!rc && !*bh)
955 		*bh = tmp;
956 
957 	return rc;
958 }
959 
960 
961 /*
962  * How many free extents have we got before we need more meta data?
963  */
ocfs2_num_free_extents(struct ocfs2_extent_tree * et)964 int ocfs2_num_free_extents(struct ocfs2_extent_tree *et)
965 {
966 	int retval;
967 	struct ocfs2_extent_list *el = NULL;
968 	struct ocfs2_extent_block *eb;
969 	struct buffer_head *eb_bh = NULL;
970 	u64 last_eb_blk = 0;
971 
972 	el = et->et_root_el;
973 	last_eb_blk = ocfs2_et_get_last_eb_blk(et);
974 
975 	if (last_eb_blk) {
976 		retval = ocfs2_read_extent_block(et->et_ci, last_eb_blk,
977 						 &eb_bh);
978 		if (retval < 0) {
979 			mlog_errno(retval);
980 			goto bail;
981 		}
982 		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
983 		el = &eb->h_list;
984 	}
985 
986 	BUG_ON(el->l_tree_depth != 0);
987 
988 	retval = le16_to_cpu(el->l_count) - le16_to_cpu(el->l_next_free_rec);
989 bail:
990 	brelse(eb_bh);
991 
992 	trace_ocfs2_num_free_extents(retval);
993 	return retval;
994 }
995 
996 /* expects array to already be allocated
997  *
998  * sets h_signature, h_blkno, h_suballoc_bit, h_suballoc_slot, and
999  * l_count for you
1000  */
ocfs2_create_new_meta_bhs(handle_t * handle,struct ocfs2_extent_tree * et,int wanted,struct ocfs2_alloc_context * meta_ac,struct buffer_head * bhs[])1001 static int ocfs2_create_new_meta_bhs(handle_t *handle,
1002 				     struct ocfs2_extent_tree *et,
1003 				     int wanted,
1004 				     struct ocfs2_alloc_context *meta_ac,
1005 				     struct buffer_head *bhs[])
1006 {
1007 	int count, status, i;
1008 	u16 suballoc_bit_start;
1009 	u32 num_got;
1010 	u64 suballoc_loc, first_blkno;
1011 	struct ocfs2_super *osb =
1012 		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
1013 	struct ocfs2_extent_block *eb;
1014 
1015 	count = 0;
1016 	while (count < wanted) {
1017 		status = ocfs2_claim_metadata(handle,
1018 					      meta_ac,
1019 					      wanted - count,
1020 					      &suballoc_loc,
1021 					      &suballoc_bit_start,
1022 					      &num_got,
1023 					      &first_blkno);
1024 		if (status < 0) {
1025 			mlog_errno(status);
1026 			goto bail;
1027 		}
1028 
1029 		for(i = count;  i < (num_got + count); i++) {
1030 			bhs[i] = sb_getblk(osb->sb, first_blkno);
1031 			if (bhs[i] == NULL) {
1032 				status = -ENOMEM;
1033 				mlog_errno(status);
1034 				goto bail;
1035 			}
1036 			ocfs2_set_new_buffer_uptodate(et->et_ci, bhs[i]);
1037 
1038 			status = ocfs2_journal_access_eb(handle, et->et_ci,
1039 							 bhs[i],
1040 							 OCFS2_JOURNAL_ACCESS_CREATE);
1041 			if (status < 0) {
1042 				mlog_errno(status);
1043 				goto bail;
1044 			}
1045 
1046 			memset(bhs[i]->b_data, 0, osb->sb->s_blocksize);
1047 			eb = (struct ocfs2_extent_block *) bhs[i]->b_data;
1048 			/* Ok, setup the minimal stuff here. */
1049 			strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
1050 			eb->h_blkno = cpu_to_le64(first_blkno);
1051 			eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
1052 			eb->h_suballoc_slot =
1053 				cpu_to_le16(meta_ac->ac_alloc_slot);
1054 			eb->h_suballoc_loc = cpu_to_le64(suballoc_loc);
1055 			eb->h_suballoc_bit = cpu_to_le16(suballoc_bit_start);
1056 			eb->h_list.l_count =
1057 				cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
1058 
1059 			suballoc_bit_start++;
1060 			first_blkno++;
1061 
1062 			/* We'll also be dirtied by the caller, so
1063 			 * this isn't absolutely necessary. */
1064 			ocfs2_journal_dirty(handle, bhs[i]);
1065 		}
1066 
1067 		count += num_got;
1068 	}
1069 
1070 	status = 0;
1071 bail:
1072 	if (status < 0) {
1073 		for(i = 0; i < wanted; i++) {
1074 			brelse(bhs[i]);
1075 			bhs[i] = NULL;
1076 		}
1077 		mlog_errno(status);
1078 	}
1079 	return status;
1080 }
1081 
1082 /*
1083  * Helper function for ocfs2_add_branch() and ocfs2_shift_tree_depth().
1084  *
1085  * Returns the sum of the rightmost extent rec logical offset and
1086  * cluster count.
1087  *
1088  * ocfs2_add_branch() uses this to determine what logical cluster
1089  * value should be populated into the leftmost new branch records.
1090  *
1091  * ocfs2_shift_tree_depth() uses this to determine the # clusters
1092  * value for the new topmost tree record.
1093  */
ocfs2_sum_rightmost_rec(struct ocfs2_extent_list * el)1094 static inline u32 ocfs2_sum_rightmost_rec(struct ocfs2_extent_list  *el)
1095 {
1096 	int i;
1097 
1098 	i = le16_to_cpu(el->l_next_free_rec) - 1;
1099 
1100 	return le32_to_cpu(el->l_recs[i].e_cpos) +
1101 		ocfs2_rec_clusters(el, &el->l_recs[i]);
1102 }
1103 
1104 /*
1105  * Change range of the branches in the right most path according to the leaf
1106  * extent block's rightmost record.
1107  */
ocfs2_adjust_rightmost_branch(handle_t * handle,struct ocfs2_extent_tree * et)1108 static int ocfs2_adjust_rightmost_branch(handle_t *handle,
1109 					 struct ocfs2_extent_tree *et)
1110 {
1111 	int status;
1112 	struct ocfs2_path *path = NULL;
1113 	struct ocfs2_extent_list *el;
1114 	struct ocfs2_extent_rec *rec;
1115 
1116 	path = ocfs2_new_path_from_et(et);
1117 	if (!path) {
1118 		status = -ENOMEM;
1119 		return status;
1120 	}
1121 
1122 	status = ocfs2_find_path(et->et_ci, path, UINT_MAX);
1123 	if (status < 0) {
1124 		mlog_errno(status);
1125 		goto out;
1126 	}
1127 
1128 	status = ocfs2_extend_trans(handle, path_num_items(path));
1129 	if (status < 0) {
1130 		mlog_errno(status);
1131 		goto out;
1132 	}
1133 
1134 	status = ocfs2_journal_access_path(et->et_ci, handle, path);
1135 	if (status < 0) {
1136 		mlog_errno(status);
1137 		goto out;
1138 	}
1139 
1140 	el = path_leaf_el(path);
1141 	rec = &el->l_recs[le16_to_cpu(el->l_next_free_rec) - 1];
1142 
1143 	ocfs2_adjust_rightmost_records(handle, et, path, rec);
1144 
1145 out:
1146 	ocfs2_free_path(path);
1147 	return status;
1148 }
1149 
1150 /*
1151  * Add an entire tree branch to our inode. eb_bh is the extent block
1152  * to start at, if we don't want to start the branch at the root
1153  * structure.
1154  *
1155  * last_eb_bh is required as we have to update it's next_leaf pointer
1156  * for the new last extent block.
1157  *
1158  * the new branch will be 'empty' in the sense that every block will
1159  * contain a single record with cluster count == 0.
1160  */
ocfs2_add_branch(handle_t * handle,struct ocfs2_extent_tree * et,struct buffer_head * eb_bh,struct buffer_head ** last_eb_bh,struct ocfs2_alloc_context * meta_ac)1161 static int ocfs2_add_branch(handle_t *handle,
1162 			    struct ocfs2_extent_tree *et,
1163 			    struct buffer_head *eb_bh,
1164 			    struct buffer_head **last_eb_bh,
1165 			    struct ocfs2_alloc_context *meta_ac)
1166 {
1167 	int status, new_blocks, i, block_given = 0;
1168 	u64 next_blkno, new_last_eb_blk;
1169 	struct buffer_head *bh;
1170 	struct buffer_head **new_eb_bhs = NULL;
1171 	struct ocfs2_extent_block *eb;
1172 	struct ocfs2_extent_list  *eb_el;
1173 	struct ocfs2_extent_list  *el;
1174 	u32 new_cpos, root_end;
1175 
1176 	BUG_ON(!last_eb_bh || !*last_eb_bh);
1177 
1178 	if (eb_bh) {
1179 		eb = (struct ocfs2_extent_block *) eb_bh->b_data;
1180 		el = &eb->h_list;
1181 	} else
1182 		el = et->et_root_el;
1183 
1184 	/* we never add a branch to a leaf. */
1185 	BUG_ON(!el->l_tree_depth);
1186 
1187 	new_blocks = le16_to_cpu(el->l_tree_depth);
1188 
1189 	eb = (struct ocfs2_extent_block *)(*last_eb_bh)->b_data;
1190 	new_cpos = ocfs2_sum_rightmost_rec(&eb->h_list);
1191 	root_end = ocfs2_sum_rightmost_rec(et->et_root_el);
1192 
1193 	/*
1194 	 * If there is a gap before the root end and the real end
1195 	 * of the righmost leaf block, we need to remove the gap
1196 	 * between new_cpos and root_end first so that the tree
1197 	 * is consistent after we add a new branch(it will start
1198 	 * from new_cpos).
1199 	 */
1200 	if (root_end > new_cpos) {
1201 		trace_ocfs2_adjust_rightmost_branch(
1202 			(unsigned long long)
1203 			ocfs2_metadata_cache_owner(et->et_ci),
1204 			root_end, new_cpos);
1205 
1206 		status = ocfs2_adjust_rightmost_branch(handle, et);
1207 		if (status) {
1208 			mlog_errno(status);
1209 			goto bail;
1210 		}
1211 	}
1212 
1213 	/* allocate the number of new eb blocks we need */
1214 	new_eb_bhs = kcalloc(new_blocks, sizeof(struct buffer_head *),
1215 			     GFP_KERNEL);
1216 	if (!new_eb_bhs) {
1217 		status = -ENOMEM;
1218 		mlog_errno(status);
1219 		goto bail;
1220 	}
1221 
1222 	/* Firstyly, try to reuse dealloc since we have already estimated how
1223 	 * many extent blocks we may use.
1224 	 */
1225 	if (!ocfs2_is_dealloc_empty(et)) {
1226 		status = ocfs2_reuse_blk_from_dealloc(handle, et,
1227 						      new_eb_bhs, new_blocks,
1228 						      &block_given);
1229 		if (status < 0) {
1230 			mlog_errno(status);
1231 			goto bail;
1232 		}
1233 	}
1234 
1235 	BUG_ON(block_given > new_blocks);
1236 
1237 	if (block_given < new_blocks) {
1238 		BUG_ON(!meta_ac);
1239 		status = ocfs2_create_new_meta_bhs(handle, et,
1240 						   new_blocks - block_given,
1241 						   meta_ac,
1242 						   &new_eb_bhs[block_given]);
1243 		if (status < 0) {
1244 			mlog_errno(status);
1245 			goto bail;
1246 		}
1247 	}
1248 
1249 	/* Note: new_eb_bhs[new_blocks - 1] is the guy which will be
1250 	 * linked with the rest of the tree.
1251 	 * conversly, new_eb_bhs[0] is the new bottommost leaf.
1252 	 *
1253 	 * when we leave the loop, new_last_eb_blk will point to the
1254 	 * newest leaf, and next_blkno will point to the topmost extent
1255 	 * block. */
1256 	next_blkno = new_last_eb_blk = 0;
1257 	for(i = 0; i < new_blocks; i++) {
1258 		bh = new_eb_bhs[i];
1259 		eb = (struct ocfs2_extent_block *) bh->b_data;
1260 		/* ocfs2_create_new_meta_bhs() should create it right! */
1261 		BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
1262 		eb_el = &eb->h_list;
1263 
1264 		status = ocfs2_journal_access_eb(handle, et->et_ci, bh,
1265 						 OCFS2_JOURNAL_ACCESS_CREATE);
1266 		if (status < 0) {
1267 			mlog_errno(status);
1268 			goto bail;
1269 		}
1270 
1271 		eb->h_next_leaf_blk = 0;
1272 		eb_el->l_tree_depth = cpu_to_le16(i);
1273 		eb_el->l_next_free_rec = cpu_to_le16(1);
1274 		/*
1275 		 * This actually counts as an empty extent as
1276 		 * c_clusters == 0
1277 		 */
1278 		eb_el->l_recs[0].e_cpos = cpu_to_le32(new_cpos);
1279 		eb_el->l_recs[0].e_blkno = cpu_to_le64(next_blkno);
1280 		/*
1281 		 * eb_el isn't always an interior node, but even leaf
1282 		 * nodes want a zero'd flags and reserved field so
1283 		 * this gets the whole 32 bits regardless of use.
1284 		 */
1285 		eb_el->l_recs[0].e_int_clusters = cpu_to_le32(0);
1286 		if (!eb_el->l_tree_depth)
1287 			new_last_eb_blk = le64_to_cpu(eb->h_blkno);
1288 
1289 		ocfs2_journal_dirty(handle, bh);
1290 		next_blkno = le64_to_cpu(eb->h_blkno);
1291 	}
1292 
1293 	/* This is a bit hairy. We want to update up to three blocks
1294 	 * here without leaving any of them in an inconsistent state
1295 	 * in case of error. We don't have to worry about
1296 	 * journal_dirty erroring as it won't unless we've aborted the
1297 	 * handle (in which case we would never be here) so reserving
1298 	 * the write with journal_access is all we need to do. */
1299 	status = ocfs2_journal_access_eb(handle, et->et_ci, *last_eb_bh,
1300 					 OCFS2_JOURNAL_ACCESS_WRITE);
1301 	if (status < 0) {
1302 		mlog_errno(status);
1303 		goto bail;
1304 	}
1305 	status = ocfs2_et_root_journal_access(handle, et,
1306 					      OCFS2_JOURNAL_ACCESS_WRITE);
1307 	if (status < 0) {
1308 		mlog_errno(status);
1309 		goto bail;
1310 	}
1311 	if (eb_bh) {
1312 		status = ocfs2_journal_access_eb(handle, et->et_ci, eb_bh,
1313 						 OCFS2_JOURNAL_ACCESS_WRITE);
1314 		if (status < 0) {
1315 			mlog_errno(status);
1316 			goto bail;
1317 		}
1318 	}
1319 
1320 	/* Link the new branch into the rest of the tree (el will
1321 	 * either be on the root_bh, or the extent block passed in. */
1322 	i = le16_to_cpu(el->l_next_free_rec);
1323 	el->l_recs[i].e_blkno = cpu_to_le64(next_blkno);
1324 	el->l_recs[i].e_cpos = cpu_to_le32(new_cpos);
1325 	el->l_recs[i].e_int_clusters = 0;
1326 	le16_add_cpu(&el->l_next_free_rec, 1);
1327 
1328 	/* fe needs a new last extent block pointer, as does the
1329 	 * next_leaf on the previously last-extent-block. */
1330 	ocfs2_et_set_last_eb_blk(et, new_last_eb_blk);
1331 
1332 	eb = (struct ocfs2_extent_block *) (*last_eb_bh)->b_data;
1333 	eb->h_next_leaf_blk = cpu_to_le64(new_last_eb_blk);
1334 
1335 	ocfs2_journal_dirty(handle, *last_eb_bh);
1336 	ocfs2_journal_dirty(handle, et->et_root_bh);
1337 	if (eb_bh)
1338 		ocfs2_journal_dirty(handle, eb_bh);
1339 
1340 	/*
1341 	 * Some callers want to track the rightmost leaf so pass it
1342 	 * back here.
1343 	 */
1344 	brelse(*last_eb_bh);
1345 	get_bh(new_eb_bhs[0]);
1346 	*last_eb_bh = new_eb_bhs[0];
1347 
1348 	status = 0;
1349 bail:
1350 	if (new_eb_bhs) {
1351 		for (i = 0; i < new_blocks; i++)
1352 			brelse(new_eb_bhs[i]);
1353 		kfree(new_eb_bhs);
1354 	}
1355 
1356 	return status;
1357 }
1358 
1359 /*
1360  * adds another level to the allocation tree.
1361  * returns back the new extent block so you can add a branch to it
1362  * after this call.
1363  */
ocfs2_shift_tree_depth(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_alloc_context * meta_ac,struct buffer_head ** ret_new_eb_bh)1364 static int ocfs2_shift_tree_depth(handle_t *handle,
1365 				  struct ocfs2_extent_tree *et,
1366 				  struct ocfs2_alloc_context *meta_ac,
1367 				  struct buffer_head **ret_new_eb_bh)
1368 {
1369 	int status, i, block_given = 0;
1370 	u32 new_clusters;
1371 	struct buffer_head *new_eb_bh = NULL;
1372 	struct ocfs2_extent_block *eb;
1373 	struct ocfs2_extent_list  *root_el;
1374 	struct ocfs2_extent_list  *eb_el;
1375 
1376 	if (!ocfs2_is_dealloc_empty(et)) {
1377 		status = ocfs2_reuse_blk_from_dealloc(handle, et,
1378 						      &new_eb_bh, 1,
1379 						      &block_given);
1380 	} else if (meta_ac) {
1381 		status = ocfs2_create_new_meta_bhs(handle, et, 1, meta_ac,
1382 						   &new_eb_bh);
1383 
1384 	} else {
1385 		BUG();
1386 	}
1387 
1388 	if (status < 0) {
1389 		mlog_errno(status);
1390 		goto bail;
1391 	}
1392 
1393 	eb = (struct ocfs2_extent_block *) new_eb_bh->b_data;
1394 	/* ocfs2_create_new_meta_bhs() should create it right! */
1395 	BUG_ON(!OCFS2_IS_VALID_EXTENT_BLOCK(eb));
1396 
1397 	eb_el = &eb->h_list;
1398 	root_el = et->et_root_el;
1399 
1400 	status = ocfs2_journal_access_eb(handle, et->et_ci, new_eb_bh,
1401 					 OCFS2_JOURNAL_ACCESS_CREATE);
1402 	if (status < 0) {
1403 		mlog_errno(status);
1404 		goto bail;
1405 	}
1406 
1407 	/* copy the root extent list data into the new extent block */
1408 	eb_el->l_tree_depth = root_el->l_tree_depth;
1409 	eb_el->l_next_free_rec = root_el->l_next_free_rec;
1410 	for (i = 0; i < le16_to_cpu(root_el->l_next_free_rec); i++)
1411 		eb_el->l_recs[i] = root_el->l_recs[i];
1412 
1413 	ocfs2_journal_dirty(handle, new_eb_bh);
1414 
1415 	status = ocfs2_et_root_journal_access(handle, et,
1416 					      OCFS2_JOURNAL_ACCESS_WRITE);
1417 	if (status < 0) {
1418 		mlog_errno(status);
1419 		goto bail;
1420 	}
1421 
1422 	new_clusters = ocfs2_sum_rightmost_rec(eb_el);
1423 
1424 	/* update root_bh now */
1425 	le16_add_cpu(&root_el->l_tree_depth, 1);
1426 	root_el->l_recs[0].e_cpos = 0;
1427 	root_el->l_recs[0].e_blkno = eb->h_blkno;
1428 	root_el->l_recs[0].e_int_clusters = cpu_to_le32(new_clusters);
1429 	for (i = 1; i < le16_to_cpu(root_el->l_next_free_rec); i++)
1430 		memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
1431 	root_el->l_next_free_rec = cpu_to_le16(1);
1432 
1433 	/* If this is our 1st tree depth shift, then last_eb_blk
1434 	 * becomes the allocated extent block */
1435 	if (root_el->l_tree_depth == cpu_to_le16(1))
1436 		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
1437 
1438 	ocfs2_journal_dirty(handle, et->et_root_bh);
1439 
1440 	*ret_new_eb_bh = new_eb_bh;
1441 	new_eb_bh = NULL;
1442 	status = 0;
1443 bail:
1444 	brelse(new_eb_bh);
1445 
1446 	return status;
1447 }
1448 
1449 /*
1450  * Should only be called when there is no space left in any of the
1451  * leaf nodes. What we want to do is find the lowest tree depth
1452  * non-leaf extent block with room for new records. There are three
1453  * valid results of this search:
1454  *
1455  * 1) a lowest extent block is found, then we pass it back in
1456  *    *lowest_eb_bh and return '0'
1457  *
1458  * 2) the search fails to find anything, but the root_el has room. We
1459  *    pass NULL back in *lowest_eb_bh, but still return '0'
1460  *
1461  * 3) the search fails to find anything AND the root_el is full, in
1462  *    which case we return > 0
1463  *
1464  * return status < 0 indicates an error.
1465  */
ocfs2_find_branch_target(struct ocfs2_extent_tree * et,struct buffer_head ** target_bh)1466 static int ocfs2_find_branch_target(struct ocfs2_extent_tree *et,
1467 				    struct buffer_head **target_bh)
1468 {
1469 	int status = 0, i;
1470 	u64 blkno;
1471 	struct ocfs2_extent_block *eb;
1472 	struct ocfs2_extent_list  *el;
1473 	struct buffer_head *bh = NULL;
1474 	struct buffer_head *lowest_bh = NULL;
1475 
1476 	*target_bh = NULL;
1477 
1478 	el = et->et_root_el;
1479 
1480 	while(le16_to_cpu(el->l_tree_depth) > 1) {
1481 		if (le16_to_cpu(el->l_next_free_rec) == 0) {
1482 			status = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
1483 					"Owner %llu has empty extent list (next_free_rec == 0)\n",
1484 					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci));
1485 			goto bail;
1486 		}
1487 		i = le16_to_cpu(el->l_next_free_rec) - 1;
1488 		blkno = le64_to_cpu(el->l_recs[i].e_blkno);
1489 		if (!blkno) {
1490 			status = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
1491 					"Owner %llu has extent list where extent # %d has no physical block start\n",
1492 					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci), i);
1493 			goto bail;
1494 		}
1495 
1496 		brelse(bh);
1497 		bh = NULL;
1498 
1499 		status = ocfs2_read_extent_block(et->et_ci, blkno, &bh);
1500 		if (status < 0) {
1501 			mlog_errno(status);
1502 			goto bail;
1503 		}
1504 
1505 		eb = (struct ocfs2_extent_block *) bh->b_data;
1506 		el = &eb->h_list;
1507 
1508 		if (le16_to_cpu(el->l_next_free_rec) <
1509 		    le16_to_cpu(el->l_count)) {
1510 			brelse(lowest_bh);
1511 			lowest_bh = bh;
1512 			get_bh(lowest_bh);
1513 		}
1514 	}
1515 
1516 	/* If we didn't find one and the fe doesn't have any room,
1517 	 * then return '1' */
1518 	el = et->et_root_el;
1519 	if (!lowest_bh && (el->l_next_free_rec == el->l_count))
1520 		status = 1;
1521 
1522 	*target_bh = lowest_bh;
1523 bail:
1524 	brelse(bh);
1525 
1526 	return status;
1527 }
1528 
1529 /*
1530  * Grow a b-tree so that it has more records.
1531  *
1532  * We might shift the tree depth in which case existing paths should
1533  * be considered invalid.
1534  *
1535  * Tree depth after the grow is returned via *final_depth.
1536  *
1537  * *last_eb_bh will be updated by ocfs2_add_branch().
1538  */
ocfs2_grow_tree(handle_t * handle,struct ocfs2_extent_tree * et,int * final_depth,struct buffer_head ** last_eb_bh,struct ocfs2_alloc_context * meta_ac)1539 static int ocfs2_grow_tree(handle_t *handle, struct ocfs2_extent_tree *et,
1540 			   int *final_depth, struct buffer_head **last_eb_bh,
1541 			   struct ocfs2_alloc_context *meta_ac)
1542 {
1543 	int ret, shift;
1544 	struct ocfs2_extent_list *el = et->et_root_el;
1545 	int depth = le16_to_cpu(el->l_tree_depth);
1546 	struct buffer_head *bh = NULL;
1547 
1548 	BUG_ON(meta_ac == NULL && ocfs2_is_dealloc_empty(et));
1549 
1550 	shift = ocfs2_find_branch_target(et, &bh);
1551 	if (shift < 0) {
1552 		ret = shift;
1553 		mlog_errno(ret);
1554 		goto out;
1555 	}
1556 
1557 	/* We traveled all the way to the bottom of the allocation tree
1558 	 * and didn't find room for any more extents - we need to add
1559 	 * another tree level */
1560 	if (shift) {
1561 		BUG_ON(bh);
1562 		trace_ocfs2_grow_tree(
1563 			(unsigned long long)
1564 			ocfs2_metadata_cache_owner(et->et_ci),
1565 			depth);
1566 
1567 		/* ocfs2_shift_tree_depth will return us a buffer with
1568 		 * the new extent block (so we can pass that to
1569 		 * ocfs2_add_branch). */
1570 		ret = ocfs2_shift_tree_depth(handle, et, meta_ac, &bh);
1571 		if (ret < 0) {
1572 			mlog_errno(ret);
1573 			goto out;
1574 		}
1575 		depth++;
1576 		if (depth == 1) {
1577 			/*
1578 			 * Special case: we have room now if we shifted from
1579 			 * tree_depth 0, so no more work needs to be done.
1580 			 *
1581 			 * We won't be calling add_branch, so pass
1582 			 * back *last_eb_bh as the new leaf. At depth
1583 			 * zero, it should always be null so there's
1584 			 * no reason to brelse.
1585 			 */
1586 			BUG_ON(*last_eb_bh);
1587 			get_bh(bh);
1588 			*last_eb_bh = bh;
1589 			goto out;
1590 		}
1591 	}
1592 
1593 	/* call ocfs2_add_branch to add the final part of the tree with
1594 	 * the new data. */
1595 	ret = ocfs2_add_branch(handle, et, bh, last_eb_bh,
1596 			       meta_ac);
1597 	if (ret < 0)
1598 		mlog_errno(ret);
1599 
1600 out:
1601 	if (final_depth)
1602 		*final_depth = depth;
1603 	brelse(bh);
1604 	return ret;
1605 }
1606 
1607 /*
1608  * This function will discard the rightmost extent record.
1609  */
ocfs2_shift_records_right(struct ocfs2_extent_list * el)1610 static void ocfs2_shift_records_right(struct ocfs2_extent_list *el)
1611 {
1612 	int next_free = le16_to_cpu(el->l_next_free_rec);
1613 	int count = le16_to_cpu(el->l_count);
1614 	unsigned int num_bytes;
1615 
1616 	BUG_ON(!next_free);
1617 	/* This will cause us to go off the end of our extent list. */
1618 	BUG_ON(next_free >= count);
1619 
1620 	num_bytes = sizeof(struct ocfs2_extent_rec) * next_free;
1621 
1622 	memmove(&el->l_recs[1], &el->l_recs[0], num_bytes);
1623 }
1624 
ocfs2_rotate_leaf(struct ocfs2_extent_list * el,struct ocfs2_extent_rec * insert_rec)1625 static void ocfs2_rotate_leaf(struct ocfs2_extent_list *el,
1626 			      struct ocfs2_extent_rec *insert_rec)
1627 {
1628 	int i, insert_index, next_free, has_empty, num_bytes;
1629 	u32 insert_cpos = le32_to_cpu(insert_rec->e_cpos);
1630 	struct ocfs2_extent_rec *rec;
1631 
1632 	next_free = le16_to_cpu(el->l_next_free_rec);
1633 	has_empty = ocfs2_is_empty_extent(&el->l_recs[0]);
1634 
1635 	BUG_ON(!next_free);
1636 
1637 	/* The tree code before us didn't allow enough room in the leaf. */
1638 	BUG_ON(el->l_next_free_rec == el->l_count && !has_empty);
1639 
1640 	/*
1641 	 * The easiest way to approach this is to just remove the
1642 	 * empty extent and temporarily decrement next_free.
1643 	 */
1644 	if (has_empty) {
1645 		/*
1646 		 * If next_free was 1 (only an empty extent), this
1647 		 * loop won't execute, which is fine. We still want
1648 		 * the decrement above to happen.
1649 		 */
1650 		for(i = 0; i < (next_free - 1); i++)
1651 			el->l_recs[i] = el->l_recs[i+1];
1652 
1653 		next_free--;
1654 	}
1655 
1656 	/*
1657 	 * Figure out what the new record index should be.
1658 	 */
1659 	for(i = 0; i < next_free; i++) {
1660 		rec = &el->l_recs[i];
1661 
1662 		if (insert_cpos < le32_to_cpu(rec->e_cpos))
1663 			break;
1664 	}
1665 	insert_index = i;
1666 
1667 	trace_ocfs2_rotate_leaf(insert_cpos, insert_index,
1668 				has_empty, next_free,
1669 				le16_to_cpu(el->l_count));
1670 
1671 	BUG_ON(insert_index < 0);
1672 	BUG_ON(insert_index >= le16_to_cpu(el->l_count));
1673 	BUG_ON(insert_index > next_free);
1674 
1675 	/*
1676 	 * No need to memmove if we're just adding to the tail.
1677 	 */
1678 	if (insert_index != next_free) {
1679 		BUG_ON(next_free >= le16_to_cpu(el->l_count));
1680 
1681 		num_bytes = next_free - insert_index;
1682 		num_bytes *= sizeof(struct ocfs2_extent_rec);
1683 		memmove(&el->l_recs[insert_index + 1],
1684 			&el->l_recs[insert_index],
1685 			num_bytes);
1686 	}
1687 
1688 	/*
1689 	 * Either we had an empty extent, and need to re-increment or
1690 	 * there was no empty extent on a non full rightmost leaf node,
1691 	 * in which case we still need to increment.
1692 	 */
1693 	next_free++;
1694 	el->l_next_free_rec = cpu_to_le16(next_free);
1695 	/*
1696 	 * Make sure none of the math above just messed up our tree.
1697 	 */
1698 	BUG_ON(le16_to_cpu(el->l_next_free_rec) > le16_to_cpu(el->l_count));
1699 
1700 	el->l_recs[insert_index] = *insert_rec;
1701 
1702 }
1703 
ocfs2_remove_empty_extent(struct ocfs2_extent_list * el)1704 static void ocfs2_remove_empty_extent(struct ocfs2_extent_list *el)
1705 {
1706 	int size, num_recs = le16_to_cpu(el->l_next_free_rec);
1707 
1708 	BUG_ON(num_recs == 0);
1709 
1710 	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
1711 		num_recs--;
1712 		size = num_recs * sizeof(struct ocfs2_extent_rec);
1713 		memmove(&el->l_recs[0], &el->l_recs[1], size);
1714 		memset(&el->l_recs[num_recs], 0,
1715 		       sizeof(struct ocfs2_extent_rec));
1716 		el->l_next_free_rec = cpu_to_le16(num_recs);
1717 	}
1718 }
1719 
1720 /*
1721  * Create an empty extent record .
1722  *
1723  * l_next_free_rec may be updated.
1724  *
1725  * If an empty extent already exists do nothing.
1726  */
ocfs2_create_empty_extent(struct ocfs2_extent_list * el)1727 static void ocfs2_create_empty_extent(struct ocfs2_extent_list *el)
1728 {
1729 	int next_free = le16_to_cpu(el->l_next_free_rec);
1730 
1731 	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
1732 
1733 	if (next_free == 0)
1734 		goto set_and_inc;
1735 
1736 	if (ocfs2_is_empty_extent(&el->l_recs[0]))
1737 		return;
1738 
1739 	mlog_bug_on_msg(el->l_count == el->l_next_free_rec,
1740 			"Asked to create an empty extent in a full list:\n"
1741 			"count = %u, tree depth = %u",
1742 			le16_to_cpu(el->l_count),
1743 			le16_to_cpu(el->l_tree_depth));
1744 
1745 	ocfs2_shift_records_right(el);
1746 
1747 set_and_inc:
1748 	le16_add_cpu(&el->l_next_free_rec, 1);
1749 	memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
1750 }
1751 
1752 /*
1753  * For a rotation which involves two leaf nodes, the "root node" is
1754  * the lowest level tree node which contains a path to both leafs. This
1755  * resulting set of information can be used to form a complete "subtree"
1756  *
1757  * This function is passed two full paths from the dinode down to a
1758  * pair of adjacent leaves. It's task is to figure out which path
1759  * index contains the subtree root - this can be the root index itself
1760  * in a worst-case rotation.
1761  *
1762  * The array index of the subtree root is passed back.
1763  */
ocfs2_find_subtree_root(struct ocfs2_extent_tree * et,struct ocfs2_path * left,struct ocfs2_path * right)1764 int ocfs2_find_subtree_root(struct ocfs2_extent_tree *et,
1765 			    struct ocfs2_path *left,
1766 			    struct ocfs2_path *right)
1767 {
1768 	int i = 0;
1769 
1770 	/*
1771 	 * Check that the caller passed in two paths from the same tree.
1772 	 */
1773 	BUG_ON(path_root_bh(left) != path_root_bh(right));
1774 
1775 	do {
1776 		i++;
1777 
1778 		/*
1779 		 * The caller didn't pass two adjacent paths.
1780 		 */
1781 		mlog_bug_on_msg(i > left->p_tree_depth,
1782 				"Owner %llu, left depth %u, right depth %u\n"
1783 				"left leaf blk %llu, right leaf blk %llu\n",
1784 				(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
1785 				left->p_tree_depth, right->p_tree_depth,
1786 				(unsigned long long)path_leaf_bh(left)->b_blocknr,
1787 				(unsigned long long)path_leaf_bh(right)->b_blocknr);
1788 	} while (left->p_node[i].bh->b_blocknr ==
1789 		 right->p_node[i].bh->b_blocknr);
1790 
1791 	return i - 1;
1792 }
1793 
1794 typedef void (path_insert_t)(void *, struct buffer_head *);
1795 
1796 /*
1797  * Traverse a btree path in search of cpos, starting at root_el.
1798  *
1799  * This code can be called with a cpos larger than the tree, in which
1800  * case it will return the rightmost path.
1801  */
__ocfs2_find_path(struct ocfs2_caching_info * ci,struct ocfs2_extent_list * root_el,u32 cpos,path_insert_t * func,void * data)1802 static int __ocfs2_find_path(struct ocfs2_caching_info *ci,
1803 			     struct ocfs2_extent_list *root_el, u32 cpos,
1804 			     path_insert_t *func, void *data)
1805 {
1806 	int i, ret = 0;
1807 	u32 range;
1808 	u64 blkno;
1809 	struct buffer_head *bh = NULL;
1810 	struct ocfs2_extent_block *eb;
1811 	struct ocfs2_extent_list *el;
1812 	struct ocfs2_extent_rec *rec;
1813 
1814 	el = root_el;
1815 	while (el->l_tree_depth) {
1816 		if (le16_to_cpu(el->l_next_free_rec) == 0) {
1817 			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1818 				    "Owner %llu has empty extent list at depth %u\n",
1819 				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1820 				    le16_to_cpu(el->l_tree_depth));
1821 			ret = -EROFS;
1822 			goto out;
1823 
1824 		}
1825 
1826 		for(i = 0; i < le16_to_cpu(el->l_next_free_rec) - 1; i++) {
1827 			rec = &el->l_recs[i];
1828 
1829 			/*
1830 			 * In the case that cpos is off the allocation
1831 			 * tree, this should just wind up returning the
1832 			 * rightmost record.
1833 			 */
1834 			range = le32_to_cpu(rec->e_cpos) +
1835 				ocfs2_rec_clusters(el, rec);
1836 			if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
1837 			    break;
1838 		}
1839 
1840 		blkno = le64_to_cpu(el->l_recs[i].e_blkno);
1841 		if (blkno == 0) {
1842 			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1843 				    "Owner %llu has bad blkno in extent list at depth %u (index %d)\n",
1844 				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1845 				    le16_to_cpu(el->l_tree_depth), i);
1846 			ret = -EROFS;
1847 			goto out;
1848 		}
1849 
1850 		brelse(bh);
1851 		bh = NULL;
1852 		ret = ocfs2_read_extent_block(ci, blkno, &bh);
1853 		if (ret) {
1854 			mlog_errno(ret);
1855 			goto out;
1856 		}
1857 
1858 		eb = (struct ocfs2_extent_block *) bh->b_data;
1859 		el = &eb->h_list;
1860 
1861 		if (le16_to_cpu(el->l_next_free_rec) >
1862 		    le16_to_cpu(el->l_count)) {
1863 			ocfs2_error(ocfs2_metadata_cache_get_super(ci),
1864 				    "Owner %llu has bad count in extent list at block %llu (next free=%u, count=%u)\n",
1865 				    (unsigned long long)ocfs2_metadata_cache_owner(ci),
1866 				    (unsigned long long)bh->b_blocknr,
1867 				    le16_to_cpu(el->l_next_free_rec),
1868 				    le16_to_cpu(el->l_count));
1869 			ret = -EROFS;
1870 			goto out;
1871 		}
1872 
1873 		if (func)
1874 			func(data, bh);
1875 	}
1876 
1877 out:
1878 	/*
1879 	 * Catch any trailing bh that the loop didn't handle.
1880 	 */
1881 	brelse(bh);
1882 
1883 	return ret;
1884 }
1885 
1886 /*
1887  * Given an initialized path (that is, it has a valid root extent
1888  * list), this function will traverse the btree in search of the path
1889  * which would contain cpos.
1890  *
1891  * The path traveled is recorded in the path structure.
1892  *
1893  * Note that this will not do any comparisons on leaf node extent
1894  * records, so it will work fine in the case that we just added a tree
1895  * branch.
1896  */
1897 struct find_path_data {
1898 	int index;
1899 	struct ocfs2_path *path;
1900 };
find_path_ins(void * data,struct buffer_head * bh)1901 static void find_path_ins(void *data, struct buffer_head *bh)
1902 {
1903 	struct find_path_data *fp = data;
1904 
1905 	get_bh(bh);
1906 	ocfs2_path_insert_eb(fp->path, fp->index, bh);
1907 	fp->index++;
1908 }
ocfs2_find_path(struct ocfs2_caching_info * ci,struct ocfs2_path * path,u32 cpos)1909 int ocfs2_find_path(struct ocfs2_caching_info *ci,
1910 		    struct ocfs2_path *path, u32 cpos)
1911 {
1912 	struct find_path_data data;
1913 
1914 	data.index = 1;
1915 	data.path = path;
1916 	return __ocfs2_find_path(ci, path_root_el(path), cpos,
1917 				 find_path_ins, &data);
1918 }
1919 
find_leaf_ins(void * data,struct buffer_head * bh)1920 static void find_leaf_ins(void *data, struct buffer_head *bh)
1921 {
1922 	struct ocfs2_extent_block *eb =(struct ocfs2_extent_block *)bh->b_data;
1923 	struct ocfs2_extent_list *el = &eb->h_list;
1924 	struct buffer_head **ret = data;
1925 
1926 	/* We want to retain only the leaf block. */
1927 	if (le16_to_cpu(el->l_tree_depth) == 0) {
1928 		get_bh(bh);
1929 		*ret = bh;
1930 	}
1931 }
1932 /*
1933  * Find the leaf block in the tree which would contain cpos. No
1934  * checking of the actual leaf is done.
1935  *
1936  * Some paths want to call this instead of allocating a path structure
1937  * and calling ocfs2_find_path().
1938  *
1939  * This function doesn't handle non btree extent lists.
1940  */
ocfs2_find_leaf(struct ocfs2_caching_info * ci,struct ocfs2_extent_list * root_el,u32 cpos,struct buffer_head ** leaf_bh)1941 int ocfs2_find_leaf(struct ocfs2_caching_info *ci,
1942 		    struct ocfs2_extent_list *root_el, u32 cpos,
1943 		    struct buffer_head **leaf_bh)
1944 {
1945 	int ret;
1946 	struct buffer_head *bh = NULL;
1947 
1948 	ret = __ocfs2_find_path(ci, root_el, cpos, find_leaf_ins, &bh);
1949 	if (ret) {
1950 		mlog_errno(ret);
1951 		goto out;
1952 	}
1953 
1954 	*leaf_bh = bh;
1955 out:
1956 	return ret;
1957 }
1958 
1959 /*
1960  * Adjust the adjacent records (left_rec, right_rec) involved in a rotation.
1961  *
1962  * Basically, we've moved stuff around at the bottom of the tree and
1963  * we need to fix up the extent records above the changes to reflect
1964  * the new changes.
1965  *
1966  * left_rec: the record on the left.
1967  * right_rec: the record to the right of left_rec
1968  * right_child_el: is the child list pointed to by right_rec
1969  *
1970  * By definition, this only works on interior nodes.
1971  */
ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec * left_rec,struct ocfs2_extent_rec * right_rec,struct ocfs2_extent_list * right_child_el)1972 static void ocfs2_adjust_adjacent_records(struct ocfs2_extent_rec *left_rec,
1973 				  struct ocfs2_extent_rec *right_rec,
1974 				  struct ocfs2_extent_list *right_child_el)
1975 {
1976 	u32 left_clusters, right_end;
1977 
1978 	/*
1979 	 * Interior nodes never have holes. Their cpos is the cpos of
1980 	 * the leftmost record in their child list. Their cluster
1981 	 * count covers the full theoretical range of their child list
1982 	 * - the range between their cpos and the cpos of the record
1983 	 * immediately to their right.
1984 	 */
1985 	left_clusters = le32_to_cpu(right_child_el->l_recs[0].e_cpos);
1986 	if (!ocfs2_rec_clusters(right_child_el, &right_child_el->l_recs[0])) {
1987 		BUG_ON(right_child_el->l_tree_depth);
1988 		BUG_ON(le16_to_cpu(right_child_el->l_next_free_rec) <= 1);
1989 		left_clusters = le32_to_cpu(right_child_el->l_recs[1].e_cpos);
1990 	}
1991 	left_clusters -= le32_to_cpu(left_rec->e_cpos);
1992 	left_rec->e_int_clusters = cpu_to_le32(left_clusters);
1993 
1994 	/*
1995 	 * Calculate the rightmost cluster count boundary before
1996 	 * moving cpos - we will need to adjust clusters after
1997 	 * updating e_cpos to keep the same highest cluster count.
1998 	 */
1999 	right_end = le32_to_cpu(right_rec->e_cpos);
2000 	right_end += le32_to_cpu(right_rec->e_int_clusters);
2001 
2002 	right_rec->e_cpos = left_rec->e_cpos;
2003 	le32_add_cpu(&right_rec->e_cpos, left_clusters);
2004 
2005 	right_end -= le32_to_cpu(right_rec->e_cpos);
2006 	right_rec->e_int_clusters = cpu_to_le32(right_end);
2007 }
2008 
2009 /*
2010  * Adjust the adjacent root node records involved in a
2011  * rotation. left_el_blkno is passed in as a key so that we can easily
2012  * find it's index in the root list.
2013  */
ocfs2_adjust_root_records(struct ocfs2_extent_list * root_el,struct ocfs2_extent_list * left_el,struct ocfs2_extent_list * right_el,u64 left_el_blkno)2014 static void ocfs2_adjust_root_records(struct ocfs2_extent_list *root_el,
2015 				      struct ocfs2_extent_list *left_el,
2016 				      struct ocfs2_extent_list *right_el,
2017 				      u64 left_el_blkno)
2018 {
2019 	int i;
2020 
2021 	BUG_ON(le16_to_cpu(root_el->l_tree_depth) <=
2022 	       le16_to_cpu(left_el->l_tree_depth));
2023 
2024 	for(i = 0; i < le16_to_cpu(root_el->l_next_free_rec) - 1; i++) {
2025 		if (le64_to_cpu(root_el->l_recs[i].e_blkno) == left_el_blkno)
2026 			break;
2027 	}
2028 
2029 	/*
2030 	 * The path walking code should have never returned a root and
2031 	 * two paths which are not adjacent.
2032 	 */
2033 	BUG_ON(i >= (le16_to_cpu(root_el->l_next_free_rec) - 1));
2034 
2035 	ocfs2_adjust_adjacent_records(&root_el->l_recs[i],
2036 				      &root_el->l_recs[i + 1], right_el);
2037 }
2038 
2039 /*
2040  * We've changed a leaf block (in right_path) and need to reflect that
2041  * change back up the subtree.
2042  *
2043  * This happens in multiple places:
2044  *   - When we've moved an extent record from the left path leaf to the right
2045  *     path leaf to make room for an empty extent in the left path leaf.
2046  *   - When our insert into the right path leaf is at the leftmost edge
2047  *     and requires an update of the path immediately to it's left. This
2048  *     can occur at the end of some types of rotation and appending inserts.
2049  *   - When we've adjusted the last extent record in the left path leaf and the
2050  *     1st extent record in the right path leaf during cross extent block merge.
2051  */
ocfs2_complete_edge_insert(handle_t * handle,struct ocfs2_path * left_path,struct ocfs2_path * right_path,int subtree_index)2052 static void ocfs2_complete_edge_insert(handle_t *handle,
2053 				       struct ocfs2_path *left_path,
2054 				       struct ocfs2_path *right_path,
2055 				       int subtree_index)
2056 {
2057 	int i, idx;
2058 	struct ocfs2_extent_list *el, *left_el, *right_el;
2059 	struct ocfs2_extent_rec *left_rec, *right_rec;
2060 	struct buffer_head *root_bh = left_path->p_node[subtree_index].bh;
2061 
2062 	/*
2063 	 * Update the counts and position values within all the
2064 	 * interior nodes to reflect the leaf rotation we just did.
2065 	 *
2066 	 * The root node is handled below the loop.
2067 	 *
2068 	 * We begin the loop with right_el and left_el pointing to the
2069 	 * leaf lists and work our way up.
2070 	 *
2071 	 * NOTE: within this loop, left_el and right_el always refer
2072 	 * to the *child* lists.
2073 	 */
2074 	left_el = path_leaf_el(left_path);
2075 	right_el = path_leaf_el(right_path);
2076 	for(i = left_path->p_tree_depth - 1; i > subtree_index; i--) {
2077 		trace_ocfs2_complete_edge_insert(i);
2078 
2079 		/*
2080 		 * One nice property of knowing that all of these
2081 		 * nodes are below the root is that we only deal with
2082 		 * the leftmost right node record and the rightmost
2083 		 * left node record.
2084 		 */
2085 		el = left_path->p_node[i].el;
2086 		idx = le16_to_cpu(left_el->l_next_free_rec) - 1;
2087 		left_rec = &el->l_recs[idx];
2088 
2089 		el = right_path->p_node[i].el;
2090 		right_rec = &el->l_recs[0];
2091 
2092 		ocfs2_adjust_adjacent_records(left_rec, right_rec, right_el);
2093 
2094 		ocfs2_journal_dirty(handle, left_path->p_node[i].bh);
2095 		ocfs2_journal_dirty(handle, right_path->p_node[i].bh);
2096 
2097 		/*
2098 		 * Setup our list pointers now so that the current
2099 		 * parents become children in the next iteration.
2100 		 */
2101 		left_el = left_path->p_node[i].el;
2102 		right_el = right_path->p_node[i].el;
2103 	}
2104 
2105 	/*
2106 	 * At the root node, adjust the two adjacent records which
2107 	 * begin our path to the leaves.
2108 	 */
2109 
2110 	el = left_path->p_node[subtree_index].el;
2111 	left_el = left_path->p_node[subtree_index + 1].el;
2112 	right_el = right_path->p_node[subtree_index + 1].el;
2113 
2114 	ocfs2_adjust_root_records(el, left_el, right_el,
2115 				  left_path->p_node[subtree_index + 1].bh->b_blocknr);
2116 
2117 	root_bh = left_path->p_node[subtree_index].bh;
2118 
2119 	ocfs2_journal_dirty(handle, root_bh);
2120 }
2121 
ocfs2_rotate_subtree_right(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path * right_path,int subtree_index)2122 static int ocfs2_rotate_subtree_right(handle_t *handle,
2123 				      struct ocfs2_extent_tree *et,
2124 				      struct ocfs2_path *left_path,
2125 				      struct ocfs2_path *right_path,
2126 				      int subtree_index)
2127 {
2128 	int ret, i;
2129 	struct buffer_head *right_leaf_bh;
2130 	struct buffer_head *left_leaf_bh = NULL;
2131 	struct buffer_head *root_bh;
2132 	struct ocfs2_extent_list *right_el, *left_el;
2133 	struct ocfs2_extent_rec move_rec;
2134 
2135 	left_leaf_bh = path_leaf_bh(left_path);
2136 	left_el = path_leaf_el(left_path);
2137 
2138 	if (left_el->l_next_free_rec != left_el->l_count) {
2139 		ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
2140 			    "Inode %llu has non-full interior leaf node %llu (next free = %u)\n",
2141 			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2142 			    (unsigned long long)left_leaf_bh->b_blocknr,
2143 			    le16_to_cpu(left_el->l_next_free_rec));
2144 		return -EROFS;
2145 	}
2146 
2147 	/*
2148 	 * This extent block may already have an empty record, so we
2149 	 * return early if so.
2150 	 */
2151 	if (ocfs2_is_empty_extent(&left_el->l_recs[0]))
2152 		return 0;
2153 
2154 	root_bh = left_path->p_node[subtree_index].bh;
2155 	BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
2156 
2157 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
2158 					   subtree_index);
2159 	if (ret) {
2160 		mlog_errno(ret);
2161 		goto out;
2162 	}
2163 
2164 	for(i = subtree_index + 1; i < path_num_items(right_path); i++) {
2165 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2166 						   right_path, i);
2167 		if (ret) {
2168 			mlog_errno(ret);
2169 			goto out;
2170 		}
2171 
2172 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2173 						   left_path, i);
2174 		if (ret) {
2175 			mlog_errno(ret);
2176 			goto out;
2177 		}
2178 	}
2179 
2180 	right_leaf_bh = path_leaf_bh(right_path);
2181 	right_el = path_leaf_el(right_path);
2182 
2183 	/* This is a code error, not a disk corruption. */
2184 	mlog_bug_on_msg(!right_el->l_next_free_rec, "Inode %llu: Rotate fails "
2185 			"because rightmost leaf block %llu is empty\n",
2186 			(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2187 			(unsigned long long)right_leaf_bh->b_blocknr);
2188 
2189 	ocfs2_create_empty_extent(right_el);
2190 
2191 	ocfs2_journal_dirty(handle, right_leaf_bh);
2192 
2193 	/* Do the copy now. */
2194 	i = le16_to_cpu(left_el->l_next_free_rec) - 1;
2195 	move_rec = left_el->l_recs[i];
2196 	right_el->l_recs[0] = move_rec;
2197 
2198 	/*
2199 	 * Clear out the record we just copied and shift everything
2200 	 * over, leaving an empty extent in the left leaf.
2201 	 *
2202 	 * We temporarily subtract from next_free_rec so that the
2203 	 * shift will lose the tail record (which is now defunct).
2204 	 */
2205 	le16_add_cpu(&left_el->l_next_free_rec, -1);
2206 	ocfs2_shift_records_right(left_el);
2207 	memset(&left_el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
2208 	le16_add_cpu(&left_el->l_next_free_rec, 1);
2209 
2210 	ocfs2_journal_dirty(handle, left_leaf_bh);
2211 
2212 	ocfs2_complete_edge_insert(handle, left_path, right_path,
2213 				   subtree_index);
2214 
2215 out:
2216 	return ret;
2217 }
2218 
2219 /*
2220  * Given a full path, determine what cpos value would return us a path
2221  * containing the leaf immediately to the left of the current one.
2222  *
2223  * Will return zero if the path passed in is already the leftmost path.
2224  */
ocfs2_find_cpos_for_left_leaf(struct super_block * sb,struct ocfs2_path * path,u32 * cpos)2225 int ocfs2_find_cpos_for_left_leaf(struct super_block *sb,
2226 				  struct ocfs2_path *path, u32 *cpos)
2227 {
2228 	int i, j, ret = 0;
2229 	u64 blkno;
2230 	struct ocfs2_extent_list *el;
2231 
2232 	BUG_ON(path->p_tree_depth == 0);
2233 
2234 	*cpos = 0;
2235 
2236 	blkno = path_leaf_bh(path)->b_blocknr;
2237 
2238 	/* Start at the tree node just above the leaf and work our way up. */
2239 	i = path->p_tree_depth - 1;
2240 	while (i >= 0) {
2241 		el = path->p_node[i].el;
2242 
2243 		/*
2244 		 * Find the extent record just before the one in our
2245 		 * path.
2246 		 */
2247 		for(j = 0; j < le16_to_cpu(el->l_next_free_rec); j++) {
2248 			if (le64_to_cpu(el->l_recs[j].e_blkno) == blkno) {
2249 				if (j == 0) {
2250 					if (i == 0) {
2251 						/*
2252 						 * We've determined that the
2253 						 * path specified is already
2254 						 * the leftmost one - return a
2255 						 * cpos of zero.
2256 						 */
2257 						goto out;
2258 					}
2259 					/*
2260 					 * The leftmost record points to our
2261 					 * leaf - we need to travel up the
2262 					 * tree one level.
2263 					 */
2264 					goto next_node;
2265 				}
2266 
2267 				*cpos = le32_to_cpu(el->l_recs[j - 1].e_cpos);
2268 				*cpos = *cpos + ocfs2_rec_clusters(el,
2269 							   &el->l_recs[j - 1]);
2270 				*cpos = *cpos - 1;
2271 				goto out;
2272 			}
2273 		}
2274 
2275 		/*
2276 		 * If we got here, we never found a valid node where
2277 		 * the tree indicated one should be.
2278 		 */
2279 		ocfs2_error(sb, "Invalid extent tree at extent block %llu\n",
2280 			    (unsigned long long)blkno);
2281 		ret = -EROFS;
2282 		goto out;
2283 
2284 next_node:
2285 		blkno = path->p_node[i].bh->b_blocknr;
2286 		i--;
2287 	}
2288 
2289 out:
2290 	return ret;
2291 }
2292 
2293 /*
2294  * Extend the transaction by enough credits to complete the rotation,
2295  * and still leave at least the original number of credits allocated
2296  * to this transaction.
2297  */
ocfs2_extend_rotate_transaction(handle_t * handle,int subtree_depth,int op_credits,struct ocfs2_path * path)2298 static int ocfs2_extend_rotate_transaction(handle_t *handle, int subtree_depth,
2299 					   int op_credits,
2300 					   struct ocfs2_path *path)
2301 {
2302 	int ret = 0;
2303 	int credits = (path->p_tree_depth - subtree_depth) * 2 + 1 + op_credits;
2304 
2305 	if (handle->h_buffer_credits < credits)
2306 		ret = ocfs2_extend_trans(handle,
2307 					 credits - handle->h_buffer_credits);
2308 
2309 	return ret;
2310 }
2311 
2312 /*
2313  * Trap the case where we're inserting into the theoretical range past
2314  * the _actual_ left leaf range. Otherwise, we'll rotate a record
2315  * whose cpos is less than ours into the right leaf.
2316  *
2317  * It's only necessary to look at the rightmost record of the left
2318  * leaf because the logic that calls us should ensure that the
2319  * theoretical ranges in the path components above the leaves are
2320  * correct.
2321  */
ocfs2_rotate_requires_path_adjustment(struct ocfs2_path * left_path,u32 insert_cpos)2322 static int ocfs2_rotate_requires_path_adjustment(struct ocfs2_path *left_path,
2323 						 u32 insert_cpos)
2324 {
2325 	struct ocfs2_extent_list *left_el;
2326 	struct ocfs2_extent_rec *rec;
2327 	int next_free;
2328 
2329 	left_el = path_leaf_el(left_path);
2330 	next_free = le16_to_cpu(left_el->l_next_free_rec);
2331 	rec = &left_el->l_recs[next_free - 1];
2332 
2333 	if (insert_cpos > le32_to_cpu(rec->e_cpos))
2334 		return 1;
2335 	return 0;
2336 }
2337 
ocfs2_leftmost_rec_contains(struct ocfs2_extent_list * el,u32 cpos)2338 static int ocfs2_leftmost_rec_contains(struct ocfs2_extent_list *el, u32 cpos)
2339 {
2340 	int next_free = le16_to_cpu(el->l_next_free_rec);
2341 	unsigned int range;
2342 	struct ocfs2_extent_rec *rec;
2343 
2344 	if (next_free == 0)
2345 		return 0;
2346 
2347 	rec = &el->l_recs[0];
2348 	if (ocfs2_is_empty_extent(rec)) {
2349 		/* Empty list. */
2350 		if (next_free == 1)
2351 			return 0;
2352 		rec = &el->l_recs[1];
2353 	}
2354 
2355 	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
2356 	if (cpos >= le32_to_cpu(rec->e_cpos) && cpos < range)
2357 		return 1;
2358 	return 0;
2359 }
2360 
2361 /*
2362  * Rotate all the records in a btree right one record, starting at insert_cpos.
2363  *
2364  * The path to the rightmost leaf should be passed in.
2365  *
2366  * The array is assumed to be large enough to hold an entire path (tree depth).
2367  *
2368  * Upon successful return from this function:
2369  *
2370  * - The 'right_path' array will contain a path to the leaf block
2371  *   whose range contains e_cpos.
2372  * - That leaf block will have a single empty extent in list index 0.
2373  * - In the case that the rotation requires a post-insert update,
2374  *   *ret_left_path will contain a valid path which can be passed to
2375  *   ocfs2_insert_path().
2376  */
ocfs2_rotate_tree_right(handle_t * handle,struct ocfs2_extent_tree * et,enum ocfs2_split_type split,u32 insert_cpos,struct ocfs2_path * right_path,struct ocfs2_path ** ret_left_path)2377 static int ocfs2_rotate_tree_right(handle_t *handle,
2378 				   struct ocfs2_extent_tree *et,
2379 				   enum ocfs2_split_type split,
2380 				   u32 insert_cpos,
2381 				   struct ocfs2_path *right_path,
2382 				   struct ocfs2_path **ret_left_path)
2383 {
2384 	int ret, start, orig_credits = handle->h_buffer_credits;
2385 	u32 cpos;
2386 	struct ocfs2_path *left_path = NULL;
2387 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
2388 
2389 	*ret_left_path = NULL;
2390 
2391 	left_path = ocfs2_new_path_from_path(right_path);
2392 	if (!left_path) {
2393 		ret = -ENOMEM;
2394 		mlog_errno(ret);
2395 		goto out;
2396 	}
2397 
2398 	ret = ocfs2_find_cpos_for_left_leaf(sb, right_path, &cpos);
2399 	if (ret) {
2400 		mlog_errno(ret);
2401 		goto out;
2402 	}
2403 
2404 	trace_ocfs2_rotate_tree_right(
2405 		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2406 		insert_cpos, cpos);
2407 
2408 	/*
2409 	 * What we want to do here is:
2410 	 *
2411 	 * 1) Start with the rightmost path.
2412 	 *
2413 	 * 2) Determine a path to the leaf block directly to the left
2414 	 *    of that leaf.
2415 	 *
2416 	 * 3) Determine the 'subtree root' - the lowest level tree node
2417 	 *    which contains a path to both leaves.
2418 	 *
2419 	 * 4) Rotate the subtree.
2420 	 *
2421 	 * 5) Find the next subtree by considering the left path to be
2422 	 *    the new right path.
2423 	 *
2424 	 * The check at the top of this while loop also accepts
2425 	 * insert_cpos == cpos because cpos is only a _theoretical_
2426 	 * value to get us the left path - insert_cpos might very well
2427 	 * be filling that hole.
2428 	 *
2429 	 * Stop at a cpos of '0' because we either started at the
2430 	 * leftmost branch (i.e., a tree with one branch and a
2431 	 * rotation inside of it), or we've gone as far as we can in
2432 	 * rotating subtrees.
2433 	 */
2434 	while (cpos && insert_cpos <= cpos) {
2435 		trace_ocfs2_rotate_tree_right(
2436 			(unsigned long long)
2437 			ocfs2_metadata_cache_owner(et->et_ci),
2438 			insert_cpos, cpos);
2439 
2440 		ret = ocfs2_find_path(et->et_ci, left_path, cpos);
2441 		if (ret) {
2442 			mlog_errno(ret);
2443 			goto out;
2444 		}
2445 
2446 		mlog_bug_on_msg(path_leaf_bh(left_path) ==
2447 				path_leaf_bh(right_path),
2448 				"Owner %llu: error during insert of %u "
2449 				"(left path cpos %u) results in two identical "
2450 				"paths ending at %llu\n",
2451 				(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2452 				insert_cpos, cpos,
2453 				(unsigned long long)
2454 				path_leaf_bh(left_path)->b_blocknr);
2455 
2456 		if (split == SPLIT_NONE &&
2457 		    ocfs2_rotate_requires_path_adjustment(left_path,
2458 							  insert_cpos)) {
2459 
2460 			/*
2461 			 * We've rotated the tree as much as we
2462 			 * should. The rest is up to
2463 			 * ocfs2_insert_path() to complete, after the
2464 			 * record insertion. We indicate this
2465 			 * situation by returning the left path.
2466 			 *
2467 			 * The reason we don't adjust the records here
2468 			 * before the record insert is that an error
2469 			 * later might break the rule where a parent
2470 			 * record e_cpos will reflect the actual
2471 			 * e_cpos of the 1st nonempty record of the
2472 			 * child list.
2473 			 */
2474 			*ret_left_path = left_path;
2475 			goto out_ret_path;
2476 		}
2477 
2478 		start = ocfs2_find_subtree_root(et, left_path, right_path);
2479 
2480 		trace_ocfs2_rotate_subtree(start,
2481 			(unsigned long long)
2482 			right_path->p_node[start].bh->b_blocknr,
2483 			right_path->p_tree_depth);
2484 
2485 		ret = ocfs2_extend_rotate_transaction(handle, start,
2486 						      orig_credits, right_path);
2487 		if (ret) {
2488 			mlog_errno(ret);
2489 			goto out;
2490 		}
2491 
2492 		ret = ocfs2_rotate_subtree_right(handle, et, left_path,
2493 						 right_path, start);
2494 		if (ret) {
2495 			mlog_errno(ret);
2496 			goto out;
2497 		}
2498 
2499 		if (split != SPLIT_NONE &&
2500 		    ocfs2_leftmost_rec_contains(path_leaf_el(right_path),
2501 						insert_cpos)) {
2502 			/*
2503 			 * A rotate moves the rightmost left leaf
2504 			 * record over to the leftmost right leaf
2505 			 * slot. If we're doing an extent split
2506 			 * instead of a real insert, then we have to
2507 			 * check that the extent to be split wasn't
2508 			 * just moved over. If it was, then we can
2509 			 * exit here, passing left_path back -
2510 			 * ocfs2_split_extent() is smart enough to
2511 			 * search both leaves.
2512 			 */
2513 			*ret_left_path = left_path;
2514 			goto out_ret_path;
2515 		}
2516 
2517 		/*
2518 		 * There is no need to re-read the next right path
2519 		 * as we know that it'll be our current left
2520 		 * path. Optimize by copying values instead.
2521 		 */
2522 		ocfs2_mv_path(right_path, left_path);
2523 
2524 		ret = ocfs2_find_cpos_for_left_leaf(sb, right_path, &cpos);
2525 		if (ret) {
2526 			mlog_errno(ret);
2527 			goto out;
2528 		}
2529 	}
2530 
2531 out:
2532 	ocfs2_free_path(left_path);
2533 
2534 out_ret_path:
2535 	return ret;
2536 }
2537 
ocfs2_update_edge_lengths(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path)2538 static int ocfs2_update_edge_lengths(handle_t *handle,
2539 				     struct ocfs2_extent_tree *et,
2540 				     struct ocfs2_path *path)
2541 {
2542 	int i, idx, ret;
2543 	struct ocfs2_extent_rec *rec;
2544 	struct ocfs2_extent_list *el;
2545 	struct ocfs2_extent_block *eb;
2546 	u32 range;
2547 
2548 	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
2549 	if (ret) {
2550 		mlog_errno(ret);
2551 		goto out;
2552 	}
2553 
2554 	/* Path should always be rightmost. */
2555 	eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
2556 	BUG_ON(eb->h_next_leaf_blk != 0ULL);
2557 
2558 	el = &eb->h_list;
2559 	BUG_ON(le16_to_cpu(el->l_next_free_rec) == 0);
2560 	idx = le16_to_cpu(el->l_next_free_rec) - 1;
2561 	rec = &el->l_recs[idx];
2562 	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
2563 
2564 	for (i = 0; i < path->p_tree_depth; i++) {
2565 		el = path->p_node[i].el;
2566 		idx = le16_to_cpu(el->l_next_free_rec) - 1;
2567 		rec = &el->l_recs[idx];
2568 
2569 		rec->e_int_clusters = cpu_to_le32(range);
2570 		le32_add_cpu(&rec->e_int_clusters, -le32_to_cpu(rec->e_cpos));
2571 
2572 		ocfs2_journal_dirty(handle, path->p_node[i].bh);
2573 	}
2574 out:
2575 	return ret;
2576 }
2577 
ocfs2_unlink_path(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_cached_dealloc_ctxt * dealloc,struct ocfs2_path * path,int unlink_start)2578 static void ocfs2_unlink_path(handle_t *handle,
2579 			      struct ocfs2_extent_tree *et,
2580 			      struct ocfs2_cached_dealloc_ctxt *dealloc,
2581 			      struct ocfs2_path *path, int unlink_start)
2582 {
2583 	int ret, i;
2584 	struct ocfs2_extent_block *eb;
2585 	struct ocfs2_extent_list *el;
2586 	struct buffer_head *bh;
2587 
2588 	for(i = unlink_start; i < path_num_items(path); i++) {
2589 		bh = path->p_node[i].bh;
2590 
2591 		eb = (struct ocfs2_extent_block *)bh->b_data;
2592 		/*
2593 		 * Not all nodes might have had their final count
2594 		 * decremented by the caller - handle this here.
2595 		 */
2596 		el = &eb->h_list;
2597 		if (le16_to_cpu(el->l_next_free_rec) > 1) {
2598 			mlog(ML_ERROR,
2599 			     "Inode %llu, attempted to remove extent block "
2600 			     "%llu with %u records\n",
2601 			     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
2602 			     (unsigned long long)le64_to_cpu(eb->h_blkno),
2603 			     le16_to_cpu(el->l_next_free_rec));
2604 
2605 			ocfs2_journal_dirty(handle, bh);
2606 			ocfs2_remove_from_cache(et->et_ci, bh);
2607 			continue;
2608 		}
2609 
2610 		el->l_next_free_rec = 0;
2611 		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
2612 
2613 		ocfs2_journal_dirty(handle, bh);
2614 
2615 		ret = ocfs2_cache_extent_block_free(dealloc, eb);
2616 		if (ret)
2617 			mlog_errno(ret);
2618 
2619 		ocfs2_remove_from_cache(et->et_ci, bh);
2620 	}
2621 }
2622 
ocfs2_unlink_subtree(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path * right_path,int subtree_index,struct ocfs2_cached_dealloc_ctxt * dealloc)2623 static void ocfs2_unlink_subtree(handle_t *handle,
2624 				 struct ocfs2_extent_tree *et,
2625 				 struct ocfs2_path *left_path,
2626 				 struct ocfs2_path *right_path,
2627 				 int subtree_index,
2628 				 struct ocfs2_cached_dealloc_ctxt *dealloc)
2629 {
2630 	int i;
2631 	struct buffer_head *root_bh = left_path->p_node[subtree_index].bh;
2632 	struct ocfs2_extent_list *root_el = left_path->p_node[subtree_index].el;
2633 	struct ocfs2_extent_block *eb;
2634 
2635 	eb = (struct ocfs2_extent_block *)right_path->p_node[subtree_index + 1].bh->b_data;
2636 
2637 	for(i = 1; i < le16_to_cpu(root_el->l_next_free_rec); i++)
2638 		if (root_el->l_recs[i].e_blkno == eb->h_blkno)
2639 			break;
2640 
2641 	BUG_ON(i >= le16_to_cpu(root_el->l_next_free_rec));
2642 
2643 	memset(&root_el->l_recs[i], 0, sizeof(struct ocfs2_extent_rec));
2644 	le16_add_cpu(&root_el->l_next_free_rec, -1);
2645 
2646 	eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
2647 	eb->h_next_leaf_blk = 0;
2648 
2649 	ocfs2_journal_dirty(handle, root_bh);
2650 	ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
2651 
2652 	ocfs2_unlink_path(handle, et, dealloc, right_path,
2653 			  subtree_index + 1);
2654 }
2655 
ocfs2_rotate_subtree_left(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path * right_path,int subtree_index,struct ocfs2_cached_dealloc_ctxt * dealloc,int * deleted)2656 static int ocfs2_rotate_subtree_left(handle_t *handle,
2657 				     struct ocfs2_extent_tree *et,
2658 				     struct ocfs2_path *left_path,
2659 				     struct ocfs2_path *right_path,
2660 				     int subtree_index,
2661 				     struct ocfs2_cached_dealloc_ctxt *dealloc,
2662 				     int *deleted)
2663 {
2664 	int ret, i, del_right_subtree = 0, right_has_empty = 0;
2665 	struct buffer_head *root_bh, *et_root_bh = path_root_bh(right_path);
2666 	struct ocfs2_extent_list *right_leaf_el, *left_leaf_el;
2667 	struct ocfs2_extent_block *eb;
2668 
2669 	*deleted = 0;
2670 
2671 	right_leaf_el = path_leaf_el(right_path);
2672 	left_leaf_el = path_leaf_el(left_path);
2673 	root_bh = left_path->p_node[subtree_index].bh;
2674 	BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
2675 
2676 	if (!ocfs2_is_empty_extent(&left_leaf_el->l_recs[0]))
2677 		return 0;
2678 
2679 	eb = (struct ocfs2_extent_block *)path_leaf_bh(right_path)->b_data;
2680 	if (ocfs2_is_empty_extent(&right_leaf_el->l_recs[0])) {
2681 		/*
2682 		 * It's legal for us to proceed if the right leaf is
2683 		 * the rightmost one and it has an empty extent. There
2684 		 * are two cases to handle - whether the leaf will be
2685 		 * empty after removal or not. If the leaf isn't empty
2686 		 * then just remove the empty extent up front. The
2687 		 * next block will handle empty leaves by flagging
2688 		 * them for unlink.
2689 		 *
2690 		 * Non rightmost leaves will throw -EAGAIN and the
2691 		 * caller can manually move the subtree and retry.
2692 		 */
2693 
2694 		if (eb->h_next_leaf_blk != 0ULL)
2695 			return -EAGAIN;
2696 
2697 		if (le16_to_cpu(right_leaf_el->l_next_free_rec) > 1) {
2698 			ret = ocfs2_journal_access_eb(handle, et->et_ci,
2699 						      path_leaf_bh(right_path),
2700 						      OCFS2_JOURNAL_ACCESS_WRITE);
2701 			if (ret) {
2702 				mlog_errno(ret);
2703 				goto out;
2704 			}
2705 
2706 			ocfs2_remove_empty_extent(right_leaf_el);
2707 		} else
2708 			right_has_empty = 1;
2709 	}
2710 
2711 	if (eb->h_next_leaf_blk == 0ULL &&
2712 	    le16_to_cpu(right_leaf_el->l_next_free_rec) == 1) {
2713 		/*
2714 		 * We have to update i_last_eb_blk during the meta
2715 		 * data delete.
2716 		 */
2717 		ret = ocfs2_et_root_journal_access(handle, et,
2718 						   OCFS2_JOURNAL_ACCESS_WRITE);
2719 		if (ret) {
2720 			mlog_errno(ret);
2721 			goto out;
2722 		}
2723 
2724 		del_right_subtree = 1;
2725 	}
2726 
2727 	/*
2728 	 * Getting here with an empty extent in the right path implies
2729 	 * that it's the rightmost path and will be deleted.
2730 	 */
2731 	BUG_ON(right_has_empty && !del_right_subtree);
2732 
2733 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
2734 					   subtree_index);
2735 	if (ret) {
2736 		mlog_errno(ret);
2737 		goto out;
2738 	}
2739 
2740 	for(i = subtree_index + 1; i < path_num_items(right_path); i++) {
2741 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2742 						   right_path, i);
2743 		if (ret) {
2744 			mlog_errno(ret);
2745 			goto out;
2746 		}
2747 
2748 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2749 						   left_path, i);
2750 		if (ret) {
2751 			mlog_errno(ret);
2752 			goto out;
2753 		}
2754 	}
2755 
2756 	if (!right_has_empty) {
2757 		/*
2758 		 * Only do this if we're moving a real
2759 		 * record. Otherwise, the action is delayed until
2760 		 * after removal of the right path in which case we
2761 		 * can do a simple shift to remove the empty extent.
2762 		 */
2763 		ocfs2_rotate_leaf(left_leaf_el, &right_leaf_el->l_recs[0]);
2764 		memset(&right_leaf_el->l_recs[0], 0,
2765 		       sizeof(struct ocfs2_extent_rec));
2766 	}
2767 	if (eb->h_next_leaf_blk == 0ULL) {
2768 		/*
2769 		 * Move recs over to get rid of empty extent, decrease
2770 		 * next_free. This is allowed to remove the last
2771 		 * extent in our leaf (setting l_next_free_rec to
2772 		 * zero) - the delete code below won't care.
2773 		 */
2774 		ocfs2_remove_empty_extent(right_leaf_el);
2775 	}
2776 
2777 	ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
2778 	ocfs2_journal_dirty(handle, path_leaf_bh(right_path));
2779 
2780 	if (del_right_subtree) {
2781 		ocfs2_unlink_subtree(handle, et, left_path, right_path,
2782 				     subtree_index, dealloc);
2783 		ret = ocfs2_update_edge_lengths(handle, et, left_path);
2784 		if (ret) {
2785 			mlog_errno(ret);
2786 			goto out;
2787 		}
2788 
2789 		eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
2790 		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
2791 
2792 		/*
2793 		 * Removal of the extent in the left leaf was skipped
2794 		 * above so we could delete the right path
2795 		 * 1st.
2796 		 */
2797 		if (right_has_empty)
2798 			ocfs2_remove_empty_extent(left_leaf_el);
2799 
2800 		ocfs2_journal_dirty(handle, et_root_bh);
2801 
2802 		*deleted = 1;
2803 	} else
2804 		ocfs2_complete_edge_insert(handle, left_path, right_path,
2805 					   subtree_index);
2806 
2807 out:
2808 	return ret;
2809 }
2810 
2811 /*
2812  * Given a full path, determine what cpos value would return us a path
2813  * containing the leaf immediately to the right of the current one.
2814  *
2815  * Will return zero if the path passed in is already the rightmost path.
2816  *
2817  * This looks similar, but is subtly different to
2818  * ocfs2_find_cpos_for_left_leaf().
2819  */
ocfs2_find_cpos_for_right_leaf(struct super_block * sb,struct ocfs2_path * path,u32 * cpos)2820 int ocfs2_find_cpos_for_right_leaf(struct super_block *sb,
2821 				   struct ocfs2_path *path, u32 *cpos)
2822 {
2823 	int i, j, ret = 0;
2824 	u64 blkno;
2825 	struct ocfs2_extent_list *el;
2826 
2827 	*cpos = 0;
2828 
2829 	if (path->p_tree_depth == 0)
2830 		return 0;
2831 
2832 	blkno = path_leaf_bh(path)->b_blocknr;
2833 
2834 	/* Start at the tree node just above the leaf and work our way up. */
2835 	i = path->p_tree_depth - 1;
2836 	while (i >= 0) {
2837 		int next_free;
2838 
2839 		el = path->p_node[i].el;
2840 
2841 		/*
2842 		 * Find the extent record just after the one in our
2843 		 * path.
2844 		 */
2845 		next_free = le16_to_cpu(el->l_next_free_rec);
2846 		for(j = 0; j < le16_to_cpu(el->l_next_free_rec); j++) {
2847 			if (le64_to_cpu(el->l_recs[j].e_blkno) == blkno) {
2848 				if (j == (next_free - 1)) {
2849 					if (i == 0) {
2850 						/*
2851 						 * We've determined that the
2852 						 * path specified is already
2853 						 * the rightmost one - return a
2854 						 * cpos of zero.
2855 						 */
2856 						goto out;
2857 					}
2858 					/*
2859 					 * The rightmost record points to our
2860 					 * leaf - we need to travel up the
2861 					 * tree one level.
2862 					 */
2863 					goto next_node;
2864 				}
2865 
2866 				*cpos = le32_to_cpu(el->l_recs[j + 1].e_cpos);
2867 				goto out;
2868 			}
2869 		}
2870 
2871 		/*
2872 		 * If we got here, we never found a valid node where
2873 		 * the tree indicated one should be.
2874 		 */
2875 		ocfs2_error(sb, "Invalid extent tree at extent block %llu\n",
2876 			    (unsigned long long)blkno);
2877 		ret = -EROFS;
2878 		goto out;
2879 
2880 next_node:
2881 		blkno = path->p_node[i].bh->b_blocknr;
2882 		i--;
2883 	}
2884 
2885 out:
2886 	return ret;
2887 }
2888 
ocfs2_rotate_rightmost_leaf_left(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path)2889 static int ocfs2_rotate_rightmost_leaf_left(handle_t *handle,
2890 					    struct ocfs2_extent_tree *et,
2891 					    struct ocfs2_path *path)
2892 {
2893 	int ret;
2894 	struct buffer_head *bh = path_leaf_bh(path);
2895 	struct ocfs2_extent_list *el = path_leaf_el(path);
2896 
2897 	if (!ocfs2_is_empty_extent(&el->l_recs[0]))
2898 		return 0;
2899 
2900 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, path,
2901 					   path_num_items(path) - 1);
2902 	if (ret) {
2903 		mlog_errno(ret);
2904 		goto out;
2905 	}
2906 
2907 	ocfs2_remove_empty_extent(el);
2908 	ocfs2_journal_dirty(handle, bh);
2909 
2910 out:
2911 	return ret;
2912 }
2913 
__ocfs2_rotate_tree_left(handle_t * handle,struct ocfs2_extent_tree * et,int orig_credits,struct ocfs2_path * path,struct ocfs2_cached_dealloc_ctxt * dealloc,struct ocfs2_path ** empty_extent_path)2914 static int __ocfs2_rotate_tree_left(handle_t *handle,
2915 				    struct ocfs2_extent_tree *et,
2916 				    int orig_credits,
2917 				    struct ocfs2_path *path,
2918 				    struct ocfs2_cached_dealloc_ctxt *dealloc,
2919 				    struct ocfs2_path **empty_extent_path)
2920 {
2921 	int ret, subtree_root, deleted;
2922 	u32 right_cpos;
2923 	struct ocfs2_path *left_path = NULL;
2924 	struct ocfs2_path *right_path = NULL;
2925 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
2926 
2927 	if (!ocfs2_is_empty_extent(&(path_leaf_el(path)->l_recs[0])))
2928 		return 0;
2929 
2930 	*empty_extent_path = NULL;
2931 
2932 	ret = ocfs2_find_cpos_for_right_leaf(sb, path, &right_cpos);
2933 	if (ret) {
2934 		mlog_errno(ret);
2935 		goto out;
2936 	}
2937 
2938 	left_path = ocfs2_new_path_from_path(path);
2939 	if (!left_path) {
2940 		ret = -ENOMEM;
2941 		mlog_errno(ret);
2942 		goto out;
2943 	}
2944 
2945 	ocfs2_cp_path(left_path, path);
2946 
2947 	right_path = ocfs2_new_path_from_path(path);
2948 	if (!right_path) {
2949 		ret = -ENOMEM;
2950 		mlog_errno(ret);
2951 		goto out;
2952 	}
2953 
2954 	while (right_cpos) {
2955 		ret = ocfs2_find_path(et->et_ci, right_path, right_cpos);
2956 		if (ret) {
2957 			mlog_errno(ret);
2958 			goto out;
2959 		}
2960 
2961 		subtree_root = ocfs2_find_subtree_root(et, left_path,
2962 						       right_path);
2963 
2964 		trace_ocfs2_rotate_subtree(subtree_root,
2965 		     (unsigned long long)
2966 		     right_path->p_node[subtree_root].bh->b_blocknr,
2967 		     right_path->p_tree_depth);
2968 
2969 		ret = ocfs2_extend_rotate_transaction(handle, 0,
2970 						      orig_credits, left_path);
2971 		if (ret) {
2972 			mlog_errno(ret);
2973 			goto out;
2974 		}
2975 
2976 		/*
2977 		 * Caller might still want to make changes to the
2978 		 * tree root, so re-add it to the journal here.
2979 		 */
2980 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
2981 						   left_path, 0);
2982 		if (ret) {
2983 			mlog_errno(ret);
2984 			goto out;
2985 		}
2986 
2987 		ret = ocfs2_rotate_subtree_left(handle, et, left_path,
2988 						right_path, subtree_root,
2989 						dealloc, &deleted);
2990 		if (ret == -EAGAIN) {
2991 			/*
2992 			 * The rotation has to temporarily stop due to
2993 			 * the right subtree having an empty
2994 			 * extent. Pass it back to the caller for a
2995 			 * fixup.
2996 			 */
2997 			*empty_extent_path = right_path;
2998 			right_path = NULL;
2999 			goto out;
3000 		}
3001 		if (ret) {
3002 			mlog_errno(ret);
3003 			goto out;
3004 		}
3005 
3006 		/*
3007 		 * The subtree rotate might have removed records on
3008 		 * the rightmost edge. If so, then rotation is
3009 		 * complete.
3010 		 */
3011 		if (deleted)
3012 			break;
3013 
3014 		ocfs2_mv_path(left_path, right_path);
3015 
3016 		ret = ocfs2_find_cpos_for_right_leaf(sb, left_path,
3017 						     &right_cpos);
3018 		if (ret) {
3019 			mlog_errno(ret);
3020 			goto out;
3021 		}
3022 	}
3023 
3024 out:
3025 	ocfs2_free_path(right_path);
3026 	ocfs2_free_path(left_path);
3027 
3028 	return ret;
3029 }
3030 
ocfs2_remove_rightmost_path(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_cached_dealloc_ctxt * dealloc)3031 static int ocfs2_remove_rightmost_path(handle_t *handle,
3032 				struct ocfs2_extent_tree *et,
3033 				struct ocfs2_path *path,
3034 				struct ocfs2_cached_dealloc_ctxt *dealloc)
3035 {
3036 	int ret, subtree_index;
3037 	u32 cpos;
3038 	struct ocfs2_path *left_path = NULL;
3039 	struct ocfs2_extent_block *eb;
3040 	struct ocfs2_extent_list *el;
3041 
3042 	ret = ocfs2_et_sanity_check(et);
3043 	if (ret)
3044 		goto out;
3045 
3046 	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
3047 	if (ret) {
3048 		mlog_errno(ret);
3049 		goto out;
3050 	}
3051 
3052 	ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3053 					    path, &cpos);
3054 	if (ret) {
3055 		mlog_errno(ret);
3056 		goto out;
3057 	}
3058 
3059 	if (cpos) {
3060 		/*
3061 		 * We have a path to the left of this one - it needs
3062 		 * an update too.
3063 		 */
3064 		left_path = ocfs2_new_path_from_path(path);
3065 		if (!left_path) {
3066 			ret = -ENOMEM;
3067 			mlog_errno(ret);
3068 			goto out;
3069 		}
3070 
3071 		ret = ocfs2_find_path(et->et_ci, left_path, cpos);
3072 		if (ret) {
3073 			mlog_errno(ret);
3074 			goto out;
3075 		}
3076 
3077 		ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
3078 		if (ret) {
3079 			mlog_errno(ret);
3080 			goto out;
3081 		}
3082 
3083 		subtree_index = ocfs2_find_subtree_root(et, left_path, path);
3084 
3085 		ocfs2_unlink_subtree(handle, et, left_path, path,
3086 				     subtree_index, dealloc);
3087 		ret = ocfs2_update_edge_lengths(handle, et, left_path);
3088 		if (ret) {
3089 			mlog_errno(ret);
3090 			goto out;
3091 		}
3092 
3093 		eb = (struct ocfs2_extent_block *)path_leaf_bh(left_path)->b_data;
3094 		ocfs2_et_set_last_eb_blk(et, le64_to_cpu(eb->h_blkno));
3095 	} else {
3096 		/*
3097 		 * 'path' is also the leftmost path which
3098 		 * means it must be the only one. This gets
3099 		 * handled differently because we want to
3100 		 * revert the root back to having extents
3101 		 * in-line.
3102 		 */
3103 		ocfs2_unlink_path(handle, et, dealloc, path, 1);
3104 
3105 		el = et->et_root_el;
3106 		el->l_tree_depth = 0;
3107 		el->l_next_free_rec = 0;
3108 		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
3109 
3110 		ocfs2_et_set_last_eb_blk(et, 0);
3111 	}
3112 
3113 	ocfs2_journal_dirty(handle, path_root_bh(path));
3114 
3115 out:
3116 	ocfs2_free_path(left_path);
3117 	return ret;
3118 }
3119 
ocfs2_remove_rightmost_empty_extent(struct ocfs2_super * osb,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_cached_dealloc_ctxt * dealloc)3120 static int ocfs2_remove_rightmost_empty_extent(struct ocfs2_super *osb,
3121 				struct ocfs2_extent_tree *et,
3122 				struct ocfs2_path *path,
3123 				struct ocfs2_cached_dealloc_ctxt *dealloc)
3124 {
3125 	handle_t *handle;
3126 	int ret;
3127 	int credits = path->p_tree_depth * 2 + 1;
3128 
3129 	handle = ocfs2_start_trans(osb, credits);
3130 	if (IS_ERR(handle)) {
3131 		ret = PTR_ERR(handle);
3132 		mlog_errno(ret);
3133 		return ret;
3134 	}
3135 
3136 	ret = ocfs2_remove_rightmost_path(handle, et, path, dealloc);
3137 	if (ret)
3138 		mlog_errno(ret);
3139 
3140 	ocfs2_commit_trans(osb, handle);
3141 	return ret;
3142 }
3143 
3144 /*
3145  * Left rotation of btree records.
3146  *
3147  * In many ways, this is (unsurprisingly) the opposite of right
3148  * rotation. We start at some non-rightmost path containing an empty
3149  * extent in the leaf block. The code works its way to the rightmost
3150  * path by rotating records to the left in every subtree.
3151  *
3152  * This is used by any code which reduces the number of extent records
3153  * in a leaf. After removal, an empty record should be placed in the
3154  * leftmost list position.
3155  *
3156  * This won't handle a length update of the rightmost path records if
3157  * the rightmost tree leaf record is removed so the caller is
3158  * responsible for detecting and correcting that.
3159  */
ocfs2_rotate_tree_left(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_cached_dealloc_ctxt * dealloc)3160 static int ocfs2_rotate_tree_left(handle_t *handle,
3161 				  struct ocfs2_extent_tree *et,
3162 				  struct ocfs2_path *path,
3163 				  struct ocfs2_cached_dealloc_ctxt *dealloc)
3164 {
3165 	int ret, orig_credits = handle->h_buffer_credits;
3166 	struct ocfs2_path *tmp_path = NULL, *restart_path = NULL;
3167 	struct ocfs2_extent_block *eb;
3168 	struct ocfs2_extent_list *el;
3169 
3170 	el = path_leaf_el(path);
3171 	if (!ocfs2_is_empty_extent(&el->l_recs[0]))
3172 		return 0;
3173 
3174 	if (path->p_tree_depth == 0) {
3175 rightmost_no_delete:
3176 		/*
3177 		 * Inline extents. This is trivially handled, so do
3178 		 * it up front.
3179 		 */
3180 		ret = ocfs2_rotate_rightmost_leaf_left(handle, et, path);
3181 		if (ret)
3182 			mlog_errno(ret);
3183 		goto out;
3184 	}
3185 
3186 	/*
3187 	 * Handle rightmost branch now. There's several cases:
3188 	 *  1) simple rotation leaving records in there. That's trivial.
3189 	 *  2) rotation requiring a branch delete - there's no more
3190 	 *     records left. Two cases of this:
3191 	 *     a) There are branches to the left.
3192 	 *     b) This is also the leftmost (the only) branch.
3193 	 *
3194 	 *  1) is handled via ocfs2_rotate_rightmost_leaf_left()
3195 	 *  2a) we need the left branch so that we can update it with the unlink
3196 	 *  2b) we need to bring the root back to inline extents.
3197 	 */
3198 
3199 	eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
3200 	el = &eb->h_list;
3201 	if (eb->h_next_leaf_blk == 0) {
3202 		/*
3203 		 * This gets a bit tricky if we're going to delete the
3204 		 * rightmost path. Get the other cases out of the way
3205 		 * 1st.
3206 		 */
3207 		if (le16_to_cpu(el->l_next_free_rec) > 1)
3208 			goto rightmost_no_delete;
3209 
3210 		if (le16_to_cpu(el->l_next_free_rec) == 0) {
3211 			ret = ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
3212 					"Owner %llu has empty extent block at %llu\n",
3213 					(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
3214 					(unsigned long long)le64_to_cpu(eb->h_blkno));
3215 			goto out;
3216 		}
3217 
3218 		/*
3219 		 * XXX: The caller can not trust "path" any more after
3220 		 * this as it will have been deleted. What do we do?
3221 		 *
3222 		 * In theory the rotate-for-merge code will never get
3223 		 * here because it'll always ask for a rotate in a
3224 		 * nonempty list.
3225 		 */
3226 
3227 		ret = ocfs2_remove_rightmost_path(handle, et, path,
3228 						  dealloc);
3229 		if (ret)
3230 			mlog_errno(ret);
3231 		goto out;
3232 	}
3233 
3234 	/*
3235 	 * Now we can loop, remembering the path we get from -EAGAIN
3236 	 * and restarting from there.
3237 	 */
3238 try_rotate:
3239 	ret = __ocfs2_rotate_tree_left(handle, et, orig_credits, path,
3240 				       dealloc, &restart_path);
3241 	if (ret && ret != -EAGAIN) {
3242 		mlog_errno(ret);
3243 		goto out;
3244 	}
3245 
3246 	while (ret == -EAGAIN) {
3247 		tmp_path = restart_path;
3248 		restart_path = NULL;
3249 
3250 		ret = __ocfs2_rotate_tree_left(handle, et, orig_credits,
3251 					       tmp_path, dealloc,
3252 					       &restart_path);
3253 		if (ret && ret != -EAGAIN) {
3254 			mlog_errno(ret);
3255 			goto out;
3256 		}
3257 
3258 		ocfs2_free_path(tmp_path);
3259 		tmp_path = NULL;
3260 
3261 		if (ret == 0)
3262 			goto try_rotate;
3263 	}
3264 
3265 out:
3266 	ocfs2_free_path(tmp_path);
3267 	ocfs2_free_path(restart_path);
3268 	return ret;
3269 }
3270 
ocfs2_cleanup_merge(struct ocfs2_extent_list * el,int index)3271 static void ocfs2_cleanup_merge(struct ocfs2_extent_list *el,
3272 				int index)
3273 {
3274 	struct ocfs2_extent_rec *rec = &el->l_recs[index];
3275 	unsigned int size;
3276 
3277 	if (rec->e_leaf_clusters == 0) {
3278 		/*
3279 		 * We consumed all of the merged-from record. An empty
3280 		 * extent cannot exist anywhere but the 1st array
3281 		 * position, so move things over if the merged-from
3282 		 * record doesn't occupy that position.
3283 		 *
3284 		 * This creates a new empty extent so the caller
3285 		 * should be smart enough to have removed any existing
3286 		 * ones.
3287 		 */
3288 		if (index > 0) {
3289 			BUG_ON(ocfs2_is_empty_extent(&el->l_recs[0]));
3290 			size = index * sizeof(struct ocfs2_extent_rec);
3291 			memmove(&el->l_recs[1], &el->l_recs[0], size);
3292 		}
3293 
3294 		/*
3295 		 * Always memset - the caller doesn't check whether it
3296 		 * created an empty extent, so there could be junk in
3297 		 * the other fields.
3298 		 */
3299 		memset(&el->l_recs[0], 0, sizeof(struct ocfs2_extent_rec));
3300 	}
3301 }
3302 
ocfs2_get_right_path(struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path ** ret_right_path)3303 static int ocfs2_get_right_path(struct ocfs2_extent_tree *et,
3304 				struct ocfs2_path *left_path,
3305 				struct ocfs2_path **ret_right_path)
3306 {
3307 	int ret;
3308 	u32 right_cpos;
3309 	struct ocfs2_path *right_path = NULL;
3310 	struct ocfs2_extent_list *left_el;
3311 
3312 	*ret_right_path = NULL;
3313 
3314 	/* This function shouldn't be called for non-trees. */
3315 	BUG_ON(left_path->p_tree_depth == 0);
3316 
3317 	left_el = path_leaf_el(left_path);
3318 	BUG_ON(left_el->l_next_free_rec != left_el->l_count);
3319 
3320 	ret = ocfs2_find_cpos_for_right_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3321 					     left_path, &right_cpos);
3322 	if (ret) {
3323 		mlog_errno(ret);
3324 		goto out;
3325 	}
3326 
3327 	/* This function shouldn't be called for the rightmost leaf. */
3328 	BUG_ON(right_cpos == 0);
3329 
3330 	right_path = ocfs2_new_path_from_path(left_path);
3331 	if (!right_path) {
3332 		ret = -ENOMEM;
3333 		mlog_errno(ret);
3334 		goto out;
3335 	}
3336 
3337 	ret = ocfs2_find_path(et->et_ci, right_path, right_cpos);
3338 	if (ret) {
3339 		mlog_errno(ret);
3340 		goto out;
3341 	}
3342 
3343 	*ret_right_path = right_path;
3344 out:
3345 	if (ret)
3346 		ocfs2_free_path(right_path);
3347 	return ret;
3348 }
3349 
3350 /*
3351  * Remove split_rec clusters from the record at index and merge them
3352  * onto the beginning of the record "next" to it.
3353  * For index < l_count - 1, the next means the extent rec at index + 1.
3354  * For index == l_count - 1, the "next" means the 1st extent rec of the
3355  * next extent block.
3356  */
ocfs2_merge_rec_right(struct ocfs2_path * left_path,handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * split_rec,int index)3357 static int ocfs2_merge_rec_right(struct ocfs2_path *left_path,
3358 				 handle_t *handle,
3359 				 struct ocfs2_extent_tree *et,
3360 				 struct ocfs2_extent_rec *split_rec,
3361 				 int index)
3362 {
3363 	int ret, next_free, i;
3364 	unsigned int split_clusters = le16_to_cpu(split_rec->e_leaf_clusters);
3365 	struct ocfs2_extent_rec *left_rec;
3366 	struct ocfs2_extent_rec *right_rec;
3367 	struct ocfs2_extent_list *right_el;
3368 	struct ocfs2_path *right_path = NULL;
3369 	int subtree_index = 0;
3370 	struct ocfs2_extent_list *el = path_leaf_el(left_path);
3371 	struct buffer_head *bh = path_leaf_bh(left_path);
3372 	struct buffer_head *root_bh = NULL;
3373 
3374 	BUG_ON(index >= le16_to_cpu(el->l_next_free_rec));
3375 	left_rec = &el->l_recs[index];
3376 
3377 	if (index == le16_to_cpu(el->l_next_free_rec) - 1 &&
3378 	    le16_to_cpu(el->l_next_free_rec) == le16_to_cpu(el->l_count)) {
3379 		/* we meet with a cross extent block merge. */
3380 		ret = ocfs2_get_right_path(et, left_path, &right_path);
3381 		if (ret) {
3382 			mlog_errno(ret);
3383 			return ret;
3384 		}
3385 
3386 		right_el = path_leaf_el(right_path);
3387 		next_free = le16_to_cpu(right_el->l_next_free_rec);
3388 		BUG_ON(next_free <= 0);
3389 		right_rec = &right_el->l_recs[0];
3390 		if (ocfs2_is_empty_extent(right_rec)) {
3391 			BUG_ON(next_free <= 1);
3392 			right_rec = &right_el->l_recs[1];
3393 		}
3394 
3395 		BUG_ON(le32_to_cpu(left_rec->e_cpos) +
3396 		       le16_to_cpu(left_rec->e_leaf_clusters) !=
3397 		       le32_to_cpu(right_rec->e_cpos));
3398 
3399 		subtree_index = ocfs2_find_subtree_root(et, left_path,
3400 							right_path);
3401 
3402 		ret = ocfs2_extend_rotate_transaction(handle, subtree_index,
3403 						      handle->h_buffer_credits,
3404 						      right_path);
3405 		if (ret) {
3406 			mlog_errno(ret);
3407 			goto out;
3408 		}
3409 
3410 		root_bh = left_path->p_node[subtree_index].bh;
3411 		BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
3412 
3413 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3414 						   subtree_index);
3415 		if (ret) {
3416 			mlog_errno(ret);
3417 			goto out;
3418 		}
3419 
3420 		for (i = subtree_index + 1;
3421 		     i < path_num_items(right_path); i++) {
3422 			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3423 							   right_path, i);
3424 			if (ret) {
3425 				mlog_errno(ret);
3426 				goto out;
3427 			}
3428 
3429 			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3430 							   left_path, i);
3431 			if (ret) {
3432 				mlog_errno(ret);
3433 				goto out;
3434 			}
3435 		}
3436 
3437 	} else {
3438 		BUG_ON(index == le16_to_cpu(el->l_next_free_rec) - 1);
3439 		right_rec = &el->l_recs[index + 1];
3440 	}
3441 
3442 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, left_path,
3443 					   path_num_items(left_path) - 1);
3444 	if (ret) {
3445 		mlog_errno(ret);
3446 		goto out;
3447 	}
3448 
3449 	le16_add_cpu(&left_rec->e_leaf_clusters, -split_clusters);
3450 
3451 	le32_add_cpu(&right_rec->e_cpos, -split_clusters);
3452 	le64_add_cpu(&right_rec->e_blkno,
3453 		     -ocfs2_clusters_to_blocks(ocfs2_metadata_cache_get_super(et->et_ci),
3454 					       split_clusters));
3455 	le16_add_cpu(&right_rec->e_leaf_clusters, split_clusters);
3456 
3457 	ocfs2_cleanup_merge(el, index);
3458 
3459 	ocfs2_journal_dirty(handle, bh);
3460 	if (right_path) {
3461 		ocfs2_journal_dirty(handle, path_leaf_bh(right_path));
3462 		ocfs2_complete_edge_insert(handle, left_path, right_path,
3463 					   subtree_index);
3464 	}
3465 out:
3466 	ocfs2_free_path(right_path);
3467 	return ret;
3468 }
3469 
ocfs2_get_left_path(struct ocfs2_extent_tree * et,struct ocfs2_path * right_path,struct ocfs2_path ** ret_left_path)3470 static int ocfs2_get_left_path(struct ocfs2_extent_tree *et,
3471 			       struct ocfs2_path *right_path,
3472 			       struct ocfs2_path **ret_left_path)
3473 {
3474 	int ret;
3475 	u32 left_cpos;
3476 	struct ocfs2_path *left_path = NULL;
3477 
3478 	*ret_left_path = NULL;
3479 
3480 	/* This function shouldn't be called for non-trees. */
3481 	BUG_ON(right_path->p_tree_depth == 0);
3482 
3483 	ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
3484 					    right_path, &left_cpos);
3485 	if (ret) {
3486 		mlog_errno(ret);
3487 		goto out;
3488 	}
3489 
3490 	/* This function shouldn't be called for the leftmost leaf. */
3491 	BUG_ON(left_cpos == 0);
3492 
3493 	left_path = ocfs2_new_path_from_path(right_path);
3494 	if (!left_path) {
3495 		ret = -ENOMEM;
3496 		mlog_errno(ret);
3497 		goto out;
3498 	}
3499 
3500 	ret = ocfs2_find_path(et->et_ci, left_path, left_cpos);
3501 	if (ret) {
3502 		mlog_errno(ret);
3503 		goto out;
3504 	}
3505 
3506 	*ret_left_path = left_path;
3507 out:
3508 	if (ret)
3509 		ocfs2_free_path(left_path);
3510 	return ret;
3511 }
3512 
3513 /*
3514  * Remove split_rec clusters from the record at index and merge them
3515  * onto the tail of the record "before" it.
3516  * For index > 0, the "before" means the extent rec at index - 1.
3517  *
3518  * For index == 0, the "before" means the last record of the previous
3519  * extent block. And there is also a situation that we may need to
3520  * remove the rightmost leaf extent block in the right_path and change
3521  * the right path to indicate the new rightmost path.
3522  */
ocfs2_merge_rec_left(struct ocfs2_path * right_path,handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * split_rec,struct ocfs2_cached_dealloc_ctxt * dealloc,int index)3523 static int ocfs2_merge_rec_left(struct ocfs2_path *right_path,
3524 				handle_t *handle,
3525 				struct ocfs2_extent_tree *et,
3526 				struct ocfs2_extent_rec *split_rec,
3527 				struct ocfs2_cached_dealloc_ctxt *dealloc,
3528 				int index)
3529 {
3530 	int ret, i, subtree_index = 0, has_empty_extent = 0;
3531 	unsigned int split_clusters = le16_to_cpu(split_rec->e_leaf_clusters);
3532 	struct ocfs2_extent_rec *left_rec;
3533 	struct ocfs2_extent_rec *right_rec;
3534 	struct ocfs2_extent_list *el = path_leaf_el(right_path);
3535 	struct buffer_head *bh = path_leaf_bh(right_path);
3536 	struct buffer_head *root_bh = NULL;
3537 	struct ocfs2_path *left_path = NULL;
3538 	struct ocfs2_extent_list *left_el;
3539 
3540 	BUG_ON(index < 0);
3541 
3542 	right_rec = &el->l_recs[index];
3543 	if (index == 0) {
3544 		/* we meet with a cross extent block merge. */
3545 		ret = ocfs2_get_left_path(et, right_path, &left_path);
3546 		if (ret) {
3547 			mlog_errno(ret);
3548 			return ret;
3549 		}
3550 
3551 		left_el = path_leaf_el(left_path);
3552 		BUG_ON(le16_to_cpu(left_el->l_next_free_rec) !=
3553 		       le16_to_cpu(left_el->l_count));
3554 
3555 		left_rec = &left_el->l_recs[
3556 				le16_to_cpu(left_el->l_next_free_rec) - 1];
3557 		BUG_ON(le32_to_cpu(left_rec->e_cpos) +
3558 		       le16_to_cpu(left_rec->e_leaf_clusters) !=
3559 		       le32_to_cpu(split_rec->e_cpos));
3560 
3561 		subtree_index = ocfs2_find_subtree_root(et, left_path,
3562 							right_path);
3563 
3564 		ret = ocfs2_extend_rotate_transaction(handle, subtree_index,
3565 						      handle->h_buffer_credits,
3566 						      left_path);
3567 		if (ret) {
3568 			mlog_errno(ret);
3569 			goto out;
3570 		}
3571 
3572 		root_bh = left_path->p_node[subtree_index].bh;
3573 		BUG_ON(root_bh != right_path->p_node[subtree_index].bh);
3574 
3575 		ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3576 						   subtree_index);
3577 		if (ret) {
3578 			mlog_errno(ret);
3579 			goto out;
3580 		}
3581 
3582 		for (i = subtree_index + 1;
3583 		     i < path_num_items(right_path); i++) {
3584 			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3585 							   right_path, i);
3586 			if (ret) {
3587 				mlog_errno(ret);
3588 				goto out;
3589 			}
3590 
3591 			ret = ocfs2_path_bh_journal_access(handle, et->et_ci,
3592 							   left_path, i);
3593 			if (ret) {
3594 				mlog_errno(ret);
3595 				goto out;
3596 			}
3597 		}
3598 	} else {
3599 		left_rec = &el->l_recs[index - 1];
3600 		if (ocfs2_is_empty_extent(&el->l_recs[0]))
3601 			has_empty_extent = 1;
3602 	}
3603 
3604 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, right_path,
3605 					   path_num_items(right_path) - 1);
3606 	if (ret) {
3607 		mlog_errno(ret);
3608 		goto out;
3609 	}
3610 
3611 	if (has_empty_extent && index == 1) {
3612 		/*
3613 		 * The easy case - we can just plop the record right in.
3614 		 */
3615 		*left_rec = *split_rec;
3616 	} else
3617 		le16_add_cpu(&left_rec->e_leaf_clusters, split_clusters);
3618 
3619 	le32_add_cpu(&right_rec->e_cpos, split_clusters);
3620 	le64_add_cpu(&right_rec->e_blkno,
3621 		     ocfs2_clusters_to_blocks(ocfs2_metadata_cache_get_super(et->et_ci),
3622 					      split_clusters));
3623 	le16_add_cpu(&right_rec->e_leaf_clusters, -split_clusters);
3624 
3625 	ocfs2_cleanup_merge(el, index);
3626 
3627 	ocfs2_journal_dirty(handle, bh);
3628 	if (left_path) {
3629 		ocfs2_journal_dirty(handle, path_leaf_bh(left_path));
3630 
3631 		/*
3632 		 * In the situation that the right_rec is empty and the extent
3633 		 * block is empty also,  ocfs2_complete_edge_insert can't handle
3634 		 * it and we need to delete the right extent block.
3635 		 */
3636 		if (le16_to_cpu(right_rec->e_leaf_clusters) == 0 &&
3637 		    le16_to_cpu(el->l_next_free_rec) == 1) {
3638 			/* extend credit for ocfs2_remove_rightmost_path */
3639 			ret = ocfs2_extend_rotate_transaction(handle, 0,
3640 					handle->h_buffer_credits,
3641 					right_path);
3642 			if (ret) {
3643 				mlog_errno(ret);
3644 				goto out;
3645 			}
3646 
3647 			ret = ocfs2_remove_rightmost_path(handle, et,
3648 							  right_path,
3649 							  dealloc);
3650 			if (ret) {
3651 				mlog_errno(ret);
3652 				goto out;
3653 			}
3654 
3655 			/* Now the rightmost extent block has been deleted.
3656 			 * So we use the new rightmost path.
3657 			 */
3658 			ocfs2_mv_path(right_path, left_path);
3659 			left_path = NULL;
3660 		} else
3661 			ocfs2_complete_edge_insert(handle, left_path,
3662 						   right_path, subtree_index);
3663 	}
3664 out:
3665 	ocfs2_free_path(left_path);
3666 	return ret;
3667 }
3668 
ocfs2_try_to_merge_extent(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,int split_index,struct ocfs2_extent_rec * split_rec,struct ocfs2_cached_dealloc_ctxt * dealloc,struct ocfs2_merge_ctxt * ctxt)3669 static int ocfs2_try_to_merge_extent(handle_t *handle,
3670 				     struct ocfs2_extent_tree *et,
3671 				     struct ocfs2_path *path,
3672 				     int split_index,
3673 				     struct ocfs2_extent_rec *split_rec,
3674 				     struct ocfs2_cached_dealloc_ctxt *dealloc,
3675 				     struct ocfs2_merge_ctxt *ctxt)
3676 {
3677 	int ret = 0;
3678 	struct ocfs2_extent_list *el = path_leaf_el(path);
3679 	struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
3680 
3681 	BUG_ON(ctxt->c_contig_type == CONTIG_NONE);
3682 
3683 	if (ctxt->c_split_covers_rec && ctxt->c_has_empty_extent) {
3684 		/* extend credit for ocfs2_remove_rightmost_path */
3685 		ret = ocfs2_extend_rotate_transaction(handle, 0,
3686 				handle->h_buffer_credits,
3687 				path);
3688 		if (ret) {
3689 			mlog_errno(ret);
3690 			goto out;
3691 		}
3692 		/*
3693 		 * The merge code will need to create an empty
3694 		 * extent to take the place of the newly
3695 		 * emptied slot. Remove any pre-existing empty
3696 		 * extents - having more than one in a leaf is
3697 		 * illegal.
3698 		 */
3699 		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3700 		if (ret) {
3701 			mlog_errno(ret);
3702 			goto out;
3703 		}
3704 		split_index--;
3705 		rec = &el->l_recs[split_index];
3706 	}
3707 
3708 	if (ctxt->c_contig_type == CONTIG_LEFTRIGHT) {
3709 		/*
3710 		 * Left-right contig implies this.
3711 		 */
3712 		BUG_ON(!ctxt->c_split_covers_rec);
3713 
3714 		/*
3715 		 * Since the leftright insert always covers the entire
3716 		 * extent, this call will delete the insert record
3717 		 * entirely, resulting in an empty extent record added to
3718 		 * the extent block.
3719 		 *
3720 		 * Since the adding of an empty extent shifts
3721 		 * everything back to the right, there's no need to
3722 		 * update split_index here.
3723 		 *
3724 		 * When the split_index is zero, we need to merge it to the
3725 		 * prevoius extent block. It is more efficient and easier
3726 		 * if we do merge_right first and merge_left later.
3727 		 */
3728 		ret = ocfs2_merge_rec_right(path, handle, et, split_rec,
3729 					    split_index);
3730 		if (ret) {
3731 			mlog_errno(ret);
3732 			goto out;
3733 		}
3734 
3735 		/*
3736 		 * We can only get this from logic error above.
3737 		 */
3738 		BUG_ON(!ocfs2_is_empty_extent(&el->l_recs[0]));
3739 
3740 		/* extend credit for ocfs2_remove_rightmost_path */
3741 		ret = ocfs2_extend_rotate_transaction(handle, 0,
3742 					handle->h_buffer_credits,
3743 					path);
3744 		if (ret) {
3745 			mlog_errno(ret);
3746 			goto out;
3747 		}
3748 
3749 		/* The merge left us with an empty extent, remove it. */
3750 		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3751 		if (ret) {
3752 			mlog_errno(ret);
3753 			goto out;
3754 		}
3755 
3756 		rec = &el->l_recs[split_index];
3757 
3758 		/*
3759 		 * Note that we don't pass split_rec here on purpose -
3760 		 * we've merged it into the rec already.
3761 		 */
3762 		ret = ocfs2_merge_rec_left(path, handle, et, rec,
3763 					   dealloc, split_index);
3764 
3765 		if (ret) {
3766 			mlog_errno(ret);
3767 			goto out;
3768 		}
3769 
3770 		/* extend credit for ocfs2_remove_rightmost_path */
3771 		ret = ocfs2_extend_rotate_transaction(handle, 0,
3772 				handle->h_buffer_credits,
3773 				path);
3774 		if (ret) {
3775 			mlog_errno(ret);
3776 			goto out;
3777 		}
3778 
3779 		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
3780 		/*
3781 		 * Error from this last rotate is not critical, so
3782 		 * print but don't bubble it up.
3783 		 */
3784 		if (ret)
3785 			mlog_errno(ret);
3786 		ret = 0;
3787 	} else {
3788 		/*
3789 		 * Merge a record to the left or right.
3790 		 *
3791 		 * 'contig_type' is relative to the existing record,
3792 		 * so for example, if we're "right contig", it's to
3793 		 * the record on the left (hence the left merge).
3794 		 */
3795 		if (ctxt->c_contig_type == CONTIG_RIGHT) {
3796 			ret = ocfs2_merge_rec_left(path, handle, et,
3797 						   split_rec, dealloc,
3798 						   split_index);
3799 			if (ret) {
3800 				mlog_errno(ret);
3801 				goto out;
3802 			}
3803 		} else {
3804 			ret = ocfs2_merge_rec_right(path, handle,
3805 						    et, split_rec,
3806 						    split_index);
3807 			if (ret) {
3808 				mlog_errno(ret);
3809 				goto out;
3810 			}
3811 		}
3812 
3813 		if (ctxt->c_split_covers_rec) {
3814 			/* extend credit for ocfs2_remove_rightmost_path */
3815 			ret = ocfs2_extend_rotate_transaction(handle, 0,
3816 					handle->h_buffer_credits,
3817 					path);
3818 			if (ret) {
3819 				mlog_errno(ret);
3820 				ret = 0;
3821 				goto out;
3822 			}
3823 
3824 			/*
3825 			 * The merge may have left an empty extent in
3826 			 * our leaf. Try to rotate it away.
3827 			 */
3828 			ret = ocfs2_rotate_tree_left(handle, et, path,
3829 						     dealloc);
3830 			if (ret)
3831 				mlog_errno(ret);
3832 			ret = 0;
3833 		}
3834 	}
3835 
3836 out:
3837 	return ret;
3838 }
3839 
ocfs2_subtract_from_rec(struct super_block * sb,enum ocfs2_split_type split,struct ocfs2_extent_rec * rec,struct ocfs2_extent_rec * split_rec)3840 static void ocfs2_subtract_from_rec(struct super_block *sb,
3841 				    enum ocfs2_split_type split,
3842 				    struct ocfs2_extent_rec *rec,
3843 				    struct ocfs2_extent_rec *split_rec)
3844 {
3845 	u64 len_blocks;
3846 
3847 	len_blocks = ocfs2_clusters_to_blocks(sb,
3848 				le16_to_cpu(split_rec->e_leaf_clusters));
3849 
3850 	if (split == SPLIT_LEFT) {
3851 		/*
3852 		 * Region is on the left edge of the existing
3853 		 * record.
3854 		 */
3855 		le32_add_cpu(&rec->e_cpos,
3856 			     le16_to_cpu(split_rec->e_leaf_clusters));
3857 		le64_add_cpu(&rec->e_blkno, len_blocks);
3858 		le16_add_cpu(&rec->e_leaf_clusters,
3859 			     -le16_to_cpu(split_rec->e_leaf_clusters));
3860 	} else {
3861 		/*
3862 		 * Region is on the right edge of the existing
3863 		 * record.
3864 		 */
3865 		le16_add_cpu(&rec->e_leaf_clusters,
3866 			     -le16_to_cpu(split_rec->e_leaf_clusters));
3867 	}
3868 }
3869 
3870 /*
3871  * Do the final bits of extent record insertion at the target leaf
3872  * list. If this leaf is part of an allocation tree, it is assumed
3873  * that the tree above has been prepared.
3874  */
ocfs2_insert_at_leaf(struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * insert_rec,struct ocfs2_extent_list * el,struct ocfs2_insert_type * insert)3875 static void ocfs2_insert_at_leaf(struct ocfs2_extent_tree *et,
3876 				 struct ocfs2_extent_rec *insert_rec,
3877 				 struct ocfs2_extent_list *el,
3878 				 struct ocfs2_insert_type *insert)
3879 {
3880 	int i = insert->ins_contig_index;
3881 	unsigned int range;
3882 	struct ocfs2_extent_rec *rec;
3883 
3884 	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
3885 
3886 	if (insert->ins_split != SPLIT_NONE) {
3887 		i = ocfs2_search_extent_list(el, le32_to_cpu(insert_rec->e_cpos));
3888 		BUG_ON(i == -1);
3889 		rec = &el->l_recs[i];
3890 		ocfs2_subtract_from_rec(ocfs2_metadata_cache_get_super(et->et_ci),
3891 					insert->ins_split, rec,
3892 					insert_rec);
3893 		goto rotate;
3894 	}
3895 
3896 	/*
3897 	 * Contiguous insert - either left or right.
3898 	 */
3899 	if (insert->ins_contig != CONTIG_NONE) {
3900 		rec = &el->l_recs[i];
3901 		if (insert->ins_contig == CONTIG_LEFT) {
3902 			rec->e_blkno = insert_rec->e_blkno;
3903 			rec->e_cpos = insert_rec->e_cpos;
3904 		}
3905 		le16_add_cpu(&rec->e_leaf_clusters,
3906 			     le16_to_cpu(insert_rec->e_leaf_clusters));
3907 		return;
3908 	}
3909 
3910 	/*
3911 	 * Handle insert into an empty leaf.
3912 	 */
3913 	if (le16_to_cpu(el->l_next_free_rec) == 0 ||
3914 	    ((le16_to_cpu(el->l_next_free_rec) == 1) &&
3915 	     ocfs2_is_empty_extent(&el->l_recs[0]))) {
3916 		el->l_recs[0] = *insert_rec;
3917 		el->l_next_free_rec = cpu_to_le16(1);
3918 		return;
3919 	}
3920 
3921 	/*
3922 	 * Appending insert.
3923 	 */
3924 	if (insert->ins_appending == APPEND_TAIL) {
3925 		i = le16_to_cpu(el->l_next_free_rec) - 1;
3926 		rec = &el->l_recs[i];
3927 		range = le32_to_cpu(rec->e_cpos)
3928 			+ le16_to_cpu(rec->e_leaf_clusters);
3929 		BUG_ON(le32_to_cpu(insert_rec->e_cpos) < range);
3930 
3931 		mlog_bug_on_msg(le16_to_cpu(el->l_next_free_rec) >=
3932 				le16_to_cpu(el->l_count),
3933 				"owner %llu, depth %u, count %u, next free %u, "
3934 				"rec.cpos %u, rec.clusters %u, "
3935 				"insert.cpos %u, insert.clusters %u\n",
3936 				ocfs2_metadata_cache_owner(et->et_ci),
3937 				le16_to_cpu(el->l_tree_depth),
3938 				le16_to_cpu(el->l_count),
3939 				le16_to_cpu(el->l_next_free_rec),
3940 				le32_to_cpu(el->l_recs[i].e_cpos),
3941 				le16_to_cpu(el->l_recs[i].e_leaf_clusters),
3942 				le32_to_cpu(insert_rec->e_cpos),
3943 				le16_to_cpu(insert_rec->e_leaf_clusters));
3944 		i++;
3945 		el->l_recs[i] = *insert_rec;
3946 		le16_add_cpu(&el->l_next_free_rec, 1);
3947 		return;
3948 	}
3949 
3950 rotate:
3951 	/*
3952 	 * Ok, we have to rotate.
3953 	 *
3954 	 * At this point, it is safe to assume that inserting into an
3955 	 * empty leaf and appending to a leaf have both been handled
3956 	 * above.
3957 	 *
3958 	 * This leaf needs to have space, either by the empty 1st
3959 	 * extent record, or by virtue of an l_next_rec < l_count.
3960 	 */
3961 	ocfs2_rotate_leaf(el, insert_rec);
3962 }
3963 
ocfs2_adjust_rightmost_records(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_extent_rec * insert_rec)3964 static void ocfs2_adjust_rightmost_records(handle_t *handle,
3965 					   struct ocfs2_extent_tree *et,
3966 					   struct ocfs2_path *path,
3967 					   struct ocfs2_extent_rec *insert_rec)
3968 {
3969 	int i, next_free;
3970 	struct buffer_head *bh;
3971 	struct ocfs2_extent_list *el;
3972 	struct ocfs2_extent_rec *rec;
3973 
3974 	/*
3975 	 * Update everything except the leaf block.
3976 	 */
3977 	for (i = 0; i < path->p_tree_depth; i++) {
3978 		bh = path->p_node[i].bh;
3979 		el = path->p_node[i].el;
3980 
3981 		next_free = le16_to_cpu(el->l_next_free_rec);
3982 		if (next_free == 0) {
3983 			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
3984 				    "Owner %llu has a bad extent list\n",
3985 				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci));
3986 			return;
3987 		}
3988 
3989 		rec = &el->l_recs[next_free - 1];
3990 
3991 		rec->e_int_clusters = insert_rec->e_cpos;
3992 		le32_add_cpu(&rec->e_int_clusters,
3993 			     le16_to_cpu(insert_rec->e_leaf_clusters));
3994 		le32_add_cpu(&rec->e_int_clusters,
3995 			     -le32_to_cpu(rec->e_cpos));
3996 
3997 		ocfs2_journal_dirty(handle, bh);
3998 	}
3999 }
4000 
ocfs2_append_rec_to_path(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * insert_rec,struct ocfs2_path * right_path,struct ocfs2_path ** ret_left_path)4001 static int ocfs2_append_rec_to_path(handle_t *handle,
4002 				    struct ocfs2_extent_tree *et,
4003 				    struct ocfs2_extent_rec *insert_rec,
4004 				    struct ocfs2_path *right_path,
4005 				    struct ocfs2_path **ret_left_path)
4006 {
4007 	int ret, next_free;
4008 	struct ocfs2_extent_list *el;
4009 	struct ocfs2_path *left_path = NULL;
4010 
4011 	*ret_left_path = NULL;
4012 
4013 	/*
4014 	 * This shouldn't happen for non-trees. The extent rec cluster
4015 	 * count manipulation below only works for interior nodes.
4016 	 */
4017 	BUG_ON(right_path->p_tree_depth == 0);
4018 
4019 	/*
4020 	 * If our appending insert is at the leftmost edge of a leaf,
4021 	 * then we might need to update the rightmost records of the
4022 	 * neighboring path.
4023 	 */
4024 	el = path_leaf_el(right_path);
4025 	next_free = le16_to_cpu(el->l_next_free_rec);
4026 	if (next_free == 0 ||
4027 	    (next_free == 1 && ocfs2_is_empty_extent(&el->l_recs[0]))) {
4028 		u32 left_cpos;
4029 
4030 		ret = ocfs2_find_cpos_for_left_leaf(ocfs2_metadata_cache_get_super(et->et_ci),
4031 						    right_path, &left_cpos);
4032 		if (ret) {
4033 			mlog_errno(ret);
4034 			goto out;
4035 		}
4036 
4037 		trace_ocfs2_append_rec_to_path(
4038 			(unsigned long long)
4039 			ocfs2_metadata_cache_owner(et->et_ci),
4040 			le32_to_cpu(insert_rec->e_cpos),
4041 			left_cpos);
4042 
4043 		/*
4044 		 * No need to worry if the append is already in the
4045 		 * leftmost leaf.
4046 		 */
4047 		if (left_cpos) {
4048 			left_path = ocfs2_new_path_from_path(right_path);
4049 			if (!left_path) {
4050 				ret = -ENOMEM;
4051 				mlog_errno(ret);
4052 				goto out;
4053 			}
4054 
4055 			ret = ocfs2_find_path(et->et_ci, left_path,
4056 					      left_cpos);
4057 			if (ret) {
4058 				mlog_errno(ret);
4059 				goto out;
4060 			}
4061 
4062 			/*
4063 			 * ocfs2_insert_path() will pass the left_path to the
4064 			 * journal for us.
4065 			 */
4066 		}
4067 	}
4068 
4069 	ret = ocfs2_journal_access_path(et->et_ci, handle, right_path);
4070 	if (ret) {
4071 		mlog_errno(ret);
4072 		goto out;
4073 	}
4074 
4075 	ocfs2_adjust_rightmost_records(handle, et, right_path, insert_rec);
4076 
4077 	*ret_left_path = left_path;
4078 	ret = 0;
4079 out:
4080 	if (ret != 0)
4081 		ocfs2_free_path(left_path);
4082 
4083 	return ret;
4084 }
4085 
ocfs2_split_record(struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path * right_path,struct ocfs2_extent_rec * split_rec,enum ocfs2_split_type split)4086 static void ocfs2_split_record(struct ocfs2_extent_tree *et,
4087 			       struct ocfs2_path *left_path,
4088 			       struct ocfs2_path *right_path,
4089 			       struct ocfs2_extent_rec *split_rec,
4090 			       enum ocfs2_split_type split)
4091 {
4092 	int index;
4093 	u32 cpos = le32_to_cpu(split_rec->e_cpos);
4094 	struct ocfs2_extent_list *left_el = NULL, *right_el, *insert_el, *el;
4095 	struct ocfs2_extent_rec *rec, *tmprec;
4096 
4097 	right_el = path_leaf_el(right_path);
4098 	if (left_path)
4099 		left_el = path_leaf_el(left_path);
4100 
4101 	el = right_el;
4102 	insert_el = right_el;
4103 	index = ocfs2_search_extent_list(el, cpos);
4104 	if (index != -1) {
4105 		if (index == 0 && left_path) {
4106 			BUG_ON(ocfs2_is_empty_extent(&el->l_recs[0]));
4107 
4108 			/*
4109 			 * This typically means that the record
4110 			 * started in the left path but moved to the
4111 			 * right as a result of rotation. We either
4112 			 * move the existing record to the left, or we
4113 			 * do the later insert there.
4114 			 *
4115 			 * In this case, the left path should always
4116 			 * exist as the rotate code will have passed
4117 			 * it back for a post-insert update.
4118 			 */
4119 
4120 			if (split == SPLIT_LEFT) {
4121 				/*
4122 				 * It's a left split. Since we know
4123 				 * that the rotate code gave us an
4124 				 * empty extent in the left path, we
4125 				 * can just do the insert there.
4126 				 */
4127 				insert_el = left_el;
4128 			} else {
4129 				/*
4130 				 * Right split - we have to move the
4131 				 * existing record over to the left
4132 				 * leaf. The insert will be into the
4133 				 * newly created empty extent in the
4134 				 * right leaf.
4135 				 */
4136 				tmprec = &right_el->l_recs[index];
4137 				ocfs2_rotate_leaf(left_el, tmprec);
4138 				el = left_el;
4139 
4140 				memset(tmprec, 0, sizeof(*tmprec));
4141 				index = ocfs2_search_extent_list(left_el, cpos);
4142 				BUG_ON(index == -1);
4143 			}
4144 		}
4145 	} else {
4146 		BUG_ON(!left_path);
4147 		BUG_ON(!ocfs2_is_empty_extent(&left_el->l_recs[0]));
4148 		/*
4149 		 * Left path is easy - we can just allow the insert to
4150 		 * happen.
4151 		 */
4152 		el = left_el;
4153 		insert_el = left_el;
4154 		index = ocfs2_search_extent_list(el, cpos);
4155 		BUG_ON(index == -1);
4156 	}
4157 
4158 	rec = &el->l_recs[index];
4159 	ocfs2_subtract_from_rec(ocfs2_metadata_cache_get_super(et->et_ci),
4160 				split, rec, split_rec);
4161 	ocfs2_rotate_leaf(insert_el, split_rec);
4162 }
4163 
4164 /*
4165  * This function only does inserts on an allocation b-tree. For tree
4166  * depth = 0, ocfs2_insert_at_leaf() is called directly.
4167  *
4168  * right_path is the path we want to do the actual insert
4169  * in. left_path should only be passed in if we need to update that
4170  * portion of the tree after an edge insert.
4171  */
ocfs2_insert_path(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * left_path,struct ocfs2_path * right_path,struct ocfs2_extent_rec * insert_rec,struct ocfs2_insert_type * insert)4172 static int ocfs2_insert_path(handle_t *handle,
4173 			     struct ocfs2_extent_tree *et,
4174 			     struct ocfs2_path *left_path,
4175 			     struct ocfs2_path *right_path,
4176 			     struct ocfs2_extent_rec *insert_rec,
4177 			     struct ocfs2_insert_type *insert)
4178 {
4179 	int ret, subtree_index;
4180 	struct buffer_head *leaf_bh = path_leaf_bh(right_path);
4181 
4182 	if (left_path) {
4183 		/*
4184 		 * There's a chance that left_path got passed back to
4185 		 * us without being accounted for in the
4186 		 * journal. Extend our transaction here to be sure we
4187 		 * can change those blocks.
4188 		 */
4189 		ret = ocfs2_extend_trans(handle, left_path->p_tree_depth);
4190 		if (ret < 0) {
4191 			mlog_errno(ret);
4192 			goto out;
4193 		}
4194 
4195 		ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
4196 		if (ret < 0) {
4197 			mlog_errno(ret);
4198 			goto out;
4199 		}
4200 	}
4201 
4202 	/*
4203 	 * Pass both paths to the journal. The majority of inserts
4204 	 * will be touching all components anyway.
4205 	 */
4206 	ret = ocfs2_journal_access_path(et->et_ci, handle, right_path);
4207 	if (ret < 0) {
4208 		mlog_errno(ret);
4209 		goto out;
4210 	}
4211 
4212 	if (insert->ins_split != SPLIT_NONE) {
4213 		/*
4214 		 * We could call ocfs2_insert_at_leaf() for some types
4215 		 * of splits, but it's easier to just let one separate
4216 		 * function sort it all out.
4217 		 */
4218 		ocfs2_split_record(et, left_path, right_path,
4219 				   insert_rec, insert->ins_split);
4220 
4221 		/*
4222 		 * Split might have modified either leaf and we don't
4223 		 * have a guarantee that the later edge insert will
4224 		 * dirty this for us.
4225 		 */
4226 		if (left_path)
4227 			ocfs2_journal_dirty(handle,
4228 					    path_leaf_bh(left_path));
4229 	} else
4230 		ocfs2_insert_at_leaf(et, insert_rec, path_leaf_el(right_path),
4231 				     insert);
4232 
4233 	ocfs2_journal_dirty(handle, leaf_bh);
4234 
4235 	if (left_path) {
4236 		/*
4237 		 * The rotate code has indicated that we need to fix
4238 		 * up portions of the tree after the insert.
4239 		 *
4240 		 * XXX: Should we extend the transaction here?
4241 		 */
4242 		subtree_index = ocfs2_find_subtree_root(et, left_path,
4243 							right_path);
4244 		ocfs2_complete_edge_insert(handle, left_path, right_path,
4245 					   subtree_index);
4246 	}
4247 
4248 	ret = 0;
4249 out:
4250 	return ret;
4251 }
4252 
ocfs2_do_insert_extent(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_extent_rec * insert_rec,struct ocfs2_insert_type * type)4253 static int ocfs2_do_insert_extent(handle_t *handle,
4254 				  struct ocfs2_extent_tree *et,
4255 				  struct ocfs2_extent_rec *insert_rec,
4256 				  struct ocfs2_insert_type *type)
4257 {
4258 	int ret, rotate = 0;
4259 	u32 cpos;
4260 	struct ocfs2_path *right_path = NULL;
4261 	struct ocfs2_path *left_path = NULL;
4262 	struct ocfs2_extent_list *el;
4263 
4264 	el = et->et_root_el;
4265 
4266 	ret = ocfs2_et_root_journal_access(handle, et,
4267 					   OCFS2_JOURNAL_ACCESS_WRITE);
4268 	if (ret) {
4269 		mlog_errno(ret);
4270 		goto out;
4271 	}
4272 
4273 	if (le16_to_cpu(el->l_tree_depth) == 0) {
4274 		ocfs2_insert_at_leaf(et, insert_rec, el, type);
4275 		goto out_update_clusters;
4276 	}
4277 
4278 	right_path = ocfs2_new_path_from_et(et);
4279 	if (!right_path) {
4280 		ret = -ENOMEM;
4281 		mlog_errno(ret);
4282 		goto out;
4283 	}
4284 
4285 	/*
4286 	 * Determine the path to start with. Rotations need the
4287 	 * rightmost path, everything else can go directly to the
4288 	 * target leaf.
4289 	 */
4290 	cpos = le32_to_cpu(insert_rec->e_cpos);
4291 	if (type->ins_appending == APPEND_NONE &&
4292 	    type->ins_contig == CONTIG_NONE) {
4293 		rotate = 1;
4294 		cpos = UINT_MAX;
4295 	}
4296 
4297 	ret = ocfs2_find_path(et->et_ci, right_path, cpos);
4298 	if (ret) {
4299 		mlog_errno(ret);
4300 		goto out;
4301 	}
4302 
4303 	/*
4304 	 * Rotations and appends need special treatment - they modify
4305 	 * parts of the tree's above them.
4306 	 *
4307 	 * Both might pass back a path immediate to the left of the
4308 	 * one being inserted to. This will be cause
4309 	 * ocfs2_insert_path() to modify the rightmost records of
4310 	 * left_path to account for an edge insert.
4311 	 *
4312 	 * XXX: When modifying this code, keep in mind that an insert
4313 	 * can wind up skipping both of these two special cases...
4314 	 */
4315 	if (rotate) {
4316 		ret = ocfs2_rotate_tree_right(handle, et, type->ins_split,
4317 					      le32_to_cpu(insert_rec->e_cpos),
4318 					      right_path, &left_path);
4319 		if (ret) {
4320 			mlog_errno(ret);
4321 			goto out;
4322 		}
4323 
4324 		/*
4325 		 * ocfs2_rotate_tree_right() might have extended the
4326 		 * transaction without re-journaling our tree root.
4327 		 */
4328 		ret = ocfs2_et_root_journal_access(handle, et,
4329 						   OCFS2_JOURNAL_ACCESS_WRITE);
4330 		if (ret) {
4331 			mlog_errno(ret);
4332 			goto out;
4333 		}
4334 	} else if (type->ins_appending == APPEND_TAIL
4335 		   && type->ins_contig != CONTIG_LEFT) {
4336 		ret = ocfs2_append_rec_to_path(handle, et, insert_rec,
4337 					       right_path, &left_path);
4338 		if (ret) {
4339 			mlog_errno(ret);
4340 			goto out;
4341 		}
4342 	}
4343 
4344 	ret = ocfs2_insert_path(handle, et, left_path, right_path,
4345 				insert_rec, type);
4346 	if (ret) {
4347 		mlog_errno(ret);
4348 		goto out;
4349 	}
4350 
4351 out_update_clusters:
4352 	if (type->ins_split == SPLIT_NONE)
4353 		ocfs2_et_update_clusters(et,
4354 					 le16_to_cpu(insert_rec->e_leaf_clusters));
4355 
4356 	ocfs2_journal_dirty(handle, et->et_root_bh);
4357 
4358 out:
4359 	ocfs2_free_path(left_path);
4360 	ocfs2_free_path(right_path);
4361 
4362 	return ret;
4363 }
4364 
ocfs2_figure_merge_contig_type(struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_extent_list * el,int index,struct ocfs2_extent_rec * split_rec,struct ocfs2_merge_ctxt * ctxt)4365 static int ocfs2_figure_merge_contig_type(struct ocfs2_extent_tree *et,
4366 			       struct ocfs2_path *path,
4367 			       struct ocfs2_extent_list *el, int index,
4368 			       struct ocfs2_extent_rec *split_rec,
4369 			       struct ocfs2_merge_ctxt *ctxt)
4370 {
4371 	int status = 0;
4372 	enum ocfs2_contig_type ret = CONTIG_NONE;
4373 	u32 left_cpos, right_cpos;
4374 	struct ocfs2_extent_rec *rec = NULL;
4375 	struct ocfs2_extent_list *new_el;
4376 	struct ocfs2_path *left_path = NULL, *right_path = NULL;
4377 	struct buffer_head *bh;
4378 	struct ocfs2_extent_block *eb;
4379 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
4380 
4381 	if (index > 0) {
4382 		rec = &el->l_recs[index - 1];
4383 	} else if (path->p_tree_depth > 0) {
4384 		status = ocfs2_find_cpos_for_left_leaf(sb, path, &left_cpos);
4385 		if (status)
4386 			goto exit;
4387 
4388 		if (left_cpos != 0) {
4389 			left_path = ocfs2_new_path_from_path(path);
4390 			if (!left_path) {
4391 				status = -ENOMEM;
4392 				mlog_errno(status);
4393 				goto exit;
4394 			}
4395 
4396 			status = ocfs2_find_path(et->et_ci, left_path,
4397 						 left_cpos);
4398 			if (status)
4399 				goto free_left_path;
4400 
4401 			new_el = path_leaf_el(left_path);
4402 
4403 			if (le16_to_cpu(new_el->l_next_free_rec) !=
4404 			    le16_to_cpu(new_el->l_count)) {
4405 				bh = path_leaf_bh(left_path);
4406 				eb = (struct ocfs2_extent_block *)bh->b_data;
4407 				status = ocfs2_error(sb,
4408 						"Extent block #%llu has an invalid l_next_free_rec of %d.  It should have matched the l_count of %d\n",
4409 						(unsigned long long)le64_to_cpu(eb->h_blkno),
4410 						le16_to_cpu(new_el->l_next_free_rec),
4411 						le16_to_cpu(new_el->l_count));
4412 				goto free_left_path;
4413 			}
4414 			rec = &new_el->l_recs[
4415 				le16_to_cpu(new_el->l_next_free_rec) - 1];
4416 		}
4417 	}
4418 
4419 	/*
4420 	 * We're careful to check for an empty extent record here -
4421 	 * the merge code will know what to do if it sees one.
4422 	 */
4423 	if (rec) {
4424 		if (index == 1 && ocfs2_is_empty_extent(rec)) {
4425 			if (split_rec->e_cpos == el->l_recs[index].e_cpos)
4426 				ret = CONTIG_RIGHT;
4427 		} else {
4428 			ret = ocfs2_et_extent_contig(et, rec, split_rec);
4429 		}
4430 	}
4431 
4432 	rec = NULL;
4433 	if (index < (le16_to_cpu(el->l_next_free_rec) - 1))
4434 		rec = &el->l_recs[index + 1];
4435 	else if (le16_to_cpu(el->l_next_free_rec) == le16_to_cpu(el->l_count) &&
4436 		 path->p_tree_depth > 0) {
4437 		status = ocfs2_find_cpos_for_right_leaf(sb, path, &right_cpos);
4438 		if (status)
4439 			goto free_left_path;
4440 
4441 		if (right_cpos == 0)
4442 			goto free_left_path;
4443 
4444 		right_path = ocfs2_new_path_from_path(path);
4445 		if (!right_path) {
4446 			status = -ENOMEM;
4447 			mlog_errno(status);
4448 			goto free_left_path;
4449 		}
4450 
4451 		status = ocfs2_find_path(et->et_ci, right_path, right_cpos);
4452 		if (status)
4453 			goto free_right_path;
4454 
4455 		new_el = path_leaf_el(right_path);
4456 		rec = &new_el->l_recs[0];
4457 		if (ocfs2_is_empty_extent(rec)) {
4458 			if (le16_to_cpu(new_el->l_next_free_rec) <= 1) {
4459 				bh = path_leaf_bh(right_path);
4460 				eb = (struct ocfs2_extent_block *)bh->b_data;
4461 				status = ocfs2_error(sb,
4462 						"Extent block #%llu has an invalid l_next_free_rec of %d\n",
4463 						(unsigned long long)le64_to_cpu(eb->h_blkno),
4464 						le16_to_cpu(new_el->l_next_free_rec));
4465 				goto free_right_path;
4466 			}
4467 			rec = &new_el->l_recs[1];
4468 		}
4469 	}
4470 
4471 	if (rec) {
4472 		enum ocfs2_contig_type contig_type;
4473 
4474 		contig_type = ocfs2_et_extent_contig(et, rec, split_rec);
4475 
4476 		if (contig_type == CONTIG_LEFT && ret == CONTIG_RIGHT)
4477 			ret = CONTIG_LEFTRIGHT;
4478 		else if (ret == CONTIG_NONE)
4479 			ret = contig_type;
4480 	}
4481 
4482 free_right_path:
4483 	ocfs2_free_path(right_path);
4484 free_left_path:
4485 	ocfs2_free_path(left_path);
4486 exit:
4487 	if (status == 0)
4488 		ctxt->c_contig_type = ret;
4489 
4490 	return status;
4491 }
4492 
ocfs2_figure_contig_type(struct ocfs2_extent_tree * et,struct ocfs2_insert_type * insert,struct ocfs2_extent_list * el,struct ocfs2_extent_rec * insert_rec)4493 static void ocfs2_figure_contig_type(struct ocfs2_extent_tree *et,
4494 				     struct ocfs2_insert_type *insert,
4495 				     struct ocfs2_extent_list *el,
4496 				     struct ocfs2_extent_rec *insert_rec)
4497 {
4498 	int i;
4499 	enum ocfs2_contig_type contig_type = CONTIG_NONE;
4500 
4501 	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
4502 
4503 	for(i = 0; i < le16_to_cpu(el->l_next_free_rec); i++) {
4504 		contig_type = ocfs2_et_extent_contig(et, &el->l_recs[i],
4505 						     insert_rec);
4506 		if (contig_type != CONTIG_NONE) {
4507 			insert->ins_contig_index = i;
4508 			break;
4509 		}
4510 	}
4511 	insert->ins_contig = contig_type;
4512 
4513 	if (insert->ins_contig != CONTIG_NONE) {
4514 		struct ocfs2_extent_rec *rec =
4515 				&el->l_recs[insert->ins_contig_index];
4516 		unsigned int len = le16_to_cpu(rec->e_leaf_clusters) +
4517 				   le16_to_cpu(insert_rec->e_leaf_clusters);
4518 
4519 		/*
4520 		 * Caller might want us to limit the size of extents, don't
4521 		 * calculate contiguousness if we might exceed that limit.
4522 		 */
4523 		if (et->et_max_leaf_clusters &&
4524 		    (len > et->et_max_leaf_clusters))
4525 			insert->ins_contig = CONTIG_NONE;
4526 	}
4527 }
4528 
4529 /*
4530  * This should only be called against the righmost leaf extent list.
4531  *
4532  * ocfs2_figure_appending_type() will figure out whether we'll have to
4533  * insert at the tail of the rightmost leaf.
4534  *
4535  * This should also work against the root extent list for tree's with 0
4536  * depth. If we consider the root extent list to be the rightmost leaf node
4537  * then the logic here makes sense.
4538  */
ocfs2_figure_appending_type(struct ocfs2_insert_type * insert,struct ocfs2_extent_list * el,struct ocfs2_extent_rec * insert_rec)4539 static void ocfs2_figure_appending_type(struct ocfs2_insert_type *insert,
4540 					struct ocfs2_extent_list *el,
4541 					struct ocfs2_extent_rec *insert_rec)
4542 {
4543 	int i;
4544 	u32 cpos = le32_to_cpu(insert_rec->e_cpos);
4545 	struct ocfs2_extent_rec *rec;
4546 
4547 	insert->ins_appending = APPEND_NONE;
4548 
4549 	BUG_ON(le16_to_cpu(el->l_tree_depth) != 0);
4550 
4551 	if (!el->l_next_free_rec)
4552 		goto set_tail_append;
4553 
4554 	if (ocfs2_is_empty_extent(&el->l_recs[0])) {
4555 		/* Were all records empty? */
4556 		if (le16_to_cpu(el->l_next_free_rec) == 1)
4557 			goto set_tail_append;
4558 	}
4559 
4560 	i = le16_to_cpu(el->l_next_free_rec) - 1;
4561 	rec = &el->l_recs[i];
4562 
4563 	if (cpos >=
4564 	    (le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)))
4565 		goto set_tail_append;
4566 
4567 	return;
4568 
4569 set_tail_append:
4570 	insert->ins_appending = APPEND_TAIL;
4571 }
4572 
4573 /*
4574  * Helper function called at the beginning of an insert.
4575  *
4576  * This computes a few things that are commonly used in the process of
4577  * inserting into the btree:
4578  *   - Whether the new extent is contiguous with an existing one.
4579  *   - The current tree depth.
4580  *   - Whether the insert is an appending one.
4581  *   - The total # of free records in the tree.
4582  *
4583  * All of the information is stored on the ocfs2_insert_type
4584  * structure.
4585  */
ocfs2_figure_insert_type(struct ocfs2_extent_tree * et,struct buffer_head ** last_eb_bh,struct ocfs2_extent_rec * insert_rec,int * free_records,struct ocfs2_insert_type * insert)4586 static int ocfs2_figure_insert_type(struct ocfs2_extent_tree *et,
4587 				    struct buffer_head **last_eb_bh,
4588 				    struct ocfs2_extent_rec *insert_rec,
4589 				    int *free_records,
4590 				    struct ocfs2_insert_type *insert)
4591 {
4592 	int ret;
4593 	struct ocfs2_extent_block *eb;
4594 	struct ocfs2_extent_list *el;
4595 	struct ocfs2_path *path = NULL;
4596 	struct buffer_head *bh = NULL;
4597 
4598 	insert->ins_split = SPLIT_NONE;
4599 
4600 	el = et->et_root_el;
4601 	insert->ins_tree_depth = le16_to_cpu(el->l_tree_depth);
4602 
4603 	if (el->l_tree_depth) {
4604 		/*
4605 		 * If we have tree depth, we read in the
4606 		 * rightmost extent block ahead of time as
4607 		 * ocfs2_figure_insert_type() and ocfs2_add_branch()
4608 		 * may want it later.
4609 		 */
4610 		ret = ocfs2_read_extent_block(et->et_ci,
4611 					      ocfs2_et_get_last_eb_blk(et),
4612 					      &bh);
4613 		if (ret) {
4614 			mlog_errno(ret);
4615 			goto out;
4616 		}
4617 		eb = (struct ocfs2_extent_block *) bh->b_data;
4618 		el = &eb->h_list;
4619 	}
4620 
4621 	/*
4622 	 * Unless we have a contiguous insert, we'll need to know if
4623 	 * there is room left in our allocation tree for another
4624 	 * extent record.
4625 	 *
4626 	 * XXX: This test is simplistic, we can search for empty
4627 	 * extent records too.
4628 	 */
4629 	*free_records = le16_to_cpu(el->l_count) -
4630 		le16_to_cpu(el->l_next_free_rec);
4631 
4632 	if (!insert->ins_tree_depth) {
4633 		ocfs2_figure_contig_type(et, insert, el, insert_rec);
4634 		ocfs2_figure_appending_type(insert, el, insert_rec);
4635 		return 0;
4636 	}
4637 
4638 	path = ocfs2_new_path_from_et(et);
4639 	if (!path) {
4640 		ret = -ENOMEM;
4641 		mlog_errno(ret);
4642 		goto out;
4643 	}
4644 
4645 	/*
4646 	 * In the case that we're inserting past what the tree
4647 	 * currently accounts for, ocfs2_find_path() will return for
4648 	 * us the rightmost tree path. This is accounted for below in
4649 	 * the appending code.
4650 	 */
4651 	ret = ocfs2_find_path(et->et_ci, path, le32_to_cpu(insert_rec->e_cpos));
4652 	if (ret) {
4653 		mlog_errno(ret);
4654 		goto out;
4655 	}
4656 
4657 	el = path_leaf_el(path);
4658 
4659 	/*
4660 	 * Now that we have the path, there's two things we want to determine:
4661 	 * 1) Contiguousness (also set contig_index if this is so)
4662 	 *
4663 	 * 2) Are we doing an append? We can trivially break this up
4664          *     into two types of appends: simple record append, or a
4665          *     rotate inside the tail leaf.
4666 	 */
4667 	ocfs2_figure_contig_type(et, insert, el, insert_rec);
4668 
4669 	/*
4670 	 * The insert code isn't quite ready to deal with all cases of
4671 	 * left contiguousness. Specifically, if it's an insert into
4672 	 * the 1st record in a leaf, it will require the adjustment of
4673 	 * cluster count on the last record of the path directly to it's
4674 	 * left. For now, just catch that case and fool the layers
4675 	 * above us. This works just fine for tree_depth == 0, which
4676 	 * is why we allow that above.
4677 	 */
4678 	if (insert->ins_contig == CONTIG_LEFT &&
4679 	    insert->ins_contig_index == 0)
4680 		insert->ins_contig = CONTIG_NONE;
4681 
4682 	/*
4683 	 * Ok, so we can simply compare against last_eb to figure out
4684 	 * whether the path doesn't exist. This will only happen in
4685 	 * the case that we're doing a tail append, so maybe we can
4686 	 * take advantage of that information somehow.
4687 	 */
4688 	if (ocfs2_et_get_last_eb_blk(et) ==
4689 	    path_leaf_bh(path)->b_blocknr) {
4690 		/*
4691 		 * Ok, ocfs2_find_path() returned us the rightmost
4692 		 * tree path. This might be an appending insert. There are
4693 		 * two cases:
4694 		 *    1) We're doing a true append at the tail:
4695 		 *	-This might even be off the end of the leaf
4696 		 *    2) We're "appending" by rotating in the tail
4697 		 */
4698 		ocfs2_figure_appending_type(insert, el, insert_rec);
4699 	}
4700 
4701 out:
4702 	ocfs2_free_path(path);
4703 
4704 	if (ret == 0)
4705 		*last_eb_bh = bh;
4706 	else
4707 		brelse(bh);
4708 	return ret;
4709 }
4710 
4711 /*
4712  * Insert an extent into a btree.
4713  *
4714  * The caller needs to update the owning btree's cluster count.
4715  */
ocfs2_insert_extent(handle_t * handle,struct ocfs2_extent_tree * et,u32 cpos,u64 start_blk,u32 new_clusters,u8 flags,struct ocfs2_alloc_context * meta_ac)4716 int ocfs2_insert_extent(handle_t *handle,
4717 			struct ocfs2_extent_tree *et,
4718 			u32 cpos,
4719 			u64 start_blk,
4720 			u32 new_clusters,
4721 			u8 flags,
4722 			struct ocfs2_alloc_context *meta_ac)
4723 {
4724 	int status;
4725 	int free_records;
4726 	struct buffer_head *last_eb_bh = NULL;
4727 	struct ocfs2_insert_type insert = {0, };
4728 	struct ocfs2_extent_rec rec;
4729 
4730 	trace_ocfs2_insert_extent_start(
4731 		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
4732 		cpos, new_clusters);
4733 
4734 	memset(&rec, 0, sizeof(rec));
4735 	rec.e_cpos = cpu_to_le32(cpos);
4736 	rec.e_blkno = cpu_to_le64(start_blk);
4737 	rec.e_leaf_clusters = cpu_to_le16(new_clusters);
4738 	rec.e_flags = flags;
4739 	status = ocfs2_et_insert_check(et, &rec);
4740 	if (status) {
4741 		mlog_errno(status);
4742 		goto bail;
4743 	}
4744 
4745 	status = ocfs2_figure_insert_type(et, &last_eb_bh, &rec,
4746 					  &free_records, &insert);
4747 	if (status < 0) {
4748 		mlog_errno(status);
4749 		goto bail;
4750 	}
4751 
4752 	trace_ocfs2_insert_extent(insert.ins_appending, insert.ins_contig,
4753 				  insert.ins_contig_index, free_records,
4754 				  insert.ins_tree_depth);
4755 
4756 	if (insert.ins_contig == CONTIG_NONE && free_records == 0) {
4757 		status = ocfs2_grow_tree(handle, et,
4758 					 &insert.ins_tree_depth, &last_eb_bh,
4759 					 meta_ac);
4760 		if (status) {
4761 			mlog_errno(status);
4762 			goto bail;
4763 		}
4764 	}
4765 
4766 	/* Finally, we can add clusters. This might rotate the tree for us. */
4767 	status = ocfs2_do_insert_extent(handle, et, &rec, &insert);
4768 	if (status < 0)
4769 		mlog_errno(status);
4770 	else
4771 		ocfs2_et_extent_map_insert(et, &rec);
4772 
4773 bail:
4774 	brelse(last_eb_bh);
4775 
4776 	return status;
4777 }
4778 
4779 /*
4780  * Allcate and add clusters into the extent b-tree.
4781  * The new clusters(clusters_to_add) will be inserted at logical_offset.
4782  * The extent b-tree's root is specified by et, and
4783  * it is not limited to the file storage. Any extent tree can use this
4784  * function if it implements the proper ocfs2_extent_tree.
4785  */
ocfs2_add_clusters_in_btree(handle_t * handle,struct ocfs2_extent_tree * et,u32 * logical_offset,u32 clusters_to_add,int mark_unwritten,struct ocfs2_alloc_context * data_ac,struct ocfs2_alloc_context * meta_ac,enum ocfs2_alloc_restarted * reason_ret)4786 int ocfs2_add_clusters_in_btree(handle_t *handle,
4787 				struct ocfs2_extent_tree *et,
4788 				u32 *logical_offset,
4789 				u32 clusters_to_add,
4790 				int mark_unwritten,
4791 				struct ocfs2_alloc_context *data_ac,
4792 				struct ocfs2_alloc_context *meta_ac,
4793 				enum ocfs2_alloc_restarted *reason_ret)
4794 {
4795 	int status = 0, err = 0;
4796 	int need_free = 0;
4797 	int free_extents;
4798 	enum ocfs2_alloc_restarted reason = RESTART_NONE;
4799 	u32 bit_off, num_bits;
4800 	u64 block;
4801 	u8 flags = 0;
4802 	struct ocfs2_super *osb =
4803 		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
4804 
4805 	BUG_ON(!clusters_to_add);
4806 
4807 	if (mark_unwritten)
4808 		flags = OCFS2_EXT_UNWRITTEN;
4809 
4810 	free_extents = ocfs2_num_free_extents(et);
4811 	if (free_extents < 0) {
4812 		status = free_extents;
4813 		mlog_errno(status);
4814 		goto leave;
4815 	}
4816 
4817 	/* there are two cases which could cause us to EAGAIN in the
4818 	 * we-need-more-metadata case:
4819 	 * 1) we haven't reserved *any*
4820 	 * 2) we are so fragmented, we've needed to add metadata too
4821 	 *    many times. */
4822 	if (!free_extents && !meta_ac) {
4823 		err = -1;
4824 		status = -EAGAIN;
4825 		reason = RESTART_META;
4826 		goto leave;
4827 	} else if ((!free_extents)
4828 		   && (ocfs2_alloc_context_bits_left(meta_ac)
4829 		       < ocfs2_extend_meta_needed(et->et_root_el))) {
4830 		err = -2;
4831 		status = -EAGAIN;
4832 		reason = RESTART_META;
4833 		goto leave;
4834 	}
4835 
4836 	status = __ocfs2_claim_clusters(handle, data_ac, 1,
4837 					clusters_to_add, &bit_off, &num_bits);
4838 	if (status < 0) {
4839 		if (status != -ENOSPC)
4840 			mlog_errno(status);
4841 		goto leave;
4842 	}
4843 
4844 	BUG_ON(num_bits > clusters_to_add);
4845 
4846 	/* reserve our write early -- insert_extent may update the tree root */
4847 	status = ocfs2_et_root_journal_access(handle, et,
4848 					      OCFS2_JOURNAL_ACCESS_WRITE);
4849 	if (status < 0) {
4850 		mlog_errno(status);
4851 		need_free = 1;
4852 		goto bail;
4853 	}
4854 
4855 	block = ocfs2_clusters_to_blocks(osb->sb, bit_off);
4856 	trace_ocfs2_add_clusters_in_btree(
4857 	     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
4858 	     bit_off, num_bits);
4859 	status = ocfs2_insert_extent(handle, et, *logical_offset, block,
4860 				     num_bits, flags, meta_ac);
4861 	if (status < 0) {
4862 		mlog_errno(status);
4863 		need_free = 1;
4864 		goto bail;
4865 	}
4866 
4867 	ocfs2_journal_dirty(handle, et->et_root_bh);
4868 
4869 	clusters_to_add -= num_bits;
4870 	*logical_offset += num_bits;
4871 
4872 	if (clusters_to_add) {
4873 		err = clusters_to_add;
4874 		status = -EAGAIN;
4875 		reason = RESTART_TRANS;
4876 	}
4877 
4878 bail:
4879 	if (need_free) {
4880 		if (data_ac->ac_which == OCFS2_AC_USE_LOCAL)
4881 			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
4882 					bit_off, num_bits);
4883 		else
4884 			ocfs2_free_clusters(handle,
4885 					data_ac->ac_inode,
4886 					data_ac->ac_bh,
4887 					ocfs2_clusters_to_blocks(osb->sb, bit_off),
4888 					num_bits);
4889 	}
4890 
4891 leave:
4892 	if (reason_ret)
4893 		*reason_ret = reason;
4894 	trace_ocfs2_add_clusters_in_btree_ret(status, reason, err);
4895 	return status;
4896 }
4897 
ocfs2_make_right_split_rec(struct super_block * sb,struct ocfs2_extent_rec * split_rec,u32 cpos,struct ocfs2_extent_rec * rec)4898 static void ocfs2_make_right_split_rec(struct super_block *sb,
4899 				       struct ocfs2_extent_rec *split_rec,
4900 				       u32 cpos,
4901 				       struct ocfs2_extent_rec *rec)
4902 {
4903 	u32 rec_cpos = le32_to_cpu(rec->e_cpos);
4904 	u32 rec_range = rec_cpos + le16_to_cpu(rec->e_leaf_clusters);
4905 
4906 	memset(split_rec, 0, sizeof(struct ocfs2_extent_rec));
4907 
4908 	split_rec->e_cpos = cpu_to_le32(cpos);
4909 	split_rec->e_leaf_clusters = cpu_to_le16(rec_range - cpos);
4910 
4911 	split_rec->e_blkno = rec->e_blkno;
4912 	le64_add_cpu(&split_rec->e_blkno,
4913 		     ocfs2_clusters_to_blocks(sb, cpos - rec_cpos));
4914 
4915 	split_rec->e_flags = rec->e_flags;
4916 }
4917 
ocfs2_split_and_insert(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct buffer_head ** last_eb_bh,int split_index,struct ocfs2_extent_rec * orig_split_rec,struct ocfs2_alloc_context * meta_ac)4918 static int ocfs2_split_and_insert(handle_t *handle,
4919 				  struct ocfs2_extent_tree *et,
4920 				  struct ocfs2_path *path,
4921 				  struct buffer_head **last_eb_bh,
4922 				  int split_index,
4923 				  struct ocfs2_extent_rec *orig_split_rec,
4924 				  struct ocfs2_alloc_context *meta_ac)
4925 {
4926 	int ret = 0, depth;
4927 	unsigned int insert_range, rec_range, do_leftright = 0;
4928 	struct ocfs2_extent_rec tmprec;
4929 	struct ocfs2_extent_list *rightmost_el;
4930 	struct ocfs2_extent_rec rec;
4931 	struct ocfs2_extent_rec split_rec = *orig_split_rec;
4932 	struct ocfs2_insert_type insert;
4933 	struct ocfs2_extent_block *eb;
4934 
4935 leftright:
4936 	/*
4937 	 * Store a copy of the record on the stack - it might move
4938 	 * around as the tree is manipulated below.
4939 	 */
4940 	rec = path_leaf_el(path)->l_recs[split_index];
4941 
4942 	rightmost_el = et->et_root_el;
4943 
4944 	depth = le16_to_cpu(rightmost_el->l_tree_depth);
4945 	if (depth) {
4946 		BUG_ON(!(*last_eb_bh));
4947 		eb = (struct ocfs2_extent_block *) (*last_eb_bh)->b_data;
4948 		rightmost_el = &eb->h_list;
4949 	}
4950 
4951 	if (le16_to_cpu(rightmost_el->l_next_free_rec) ==
4952 	    le16_to_cpu(rightmost_el->l_count)) {
4953 		ret = ocfs2_grow_tree(handle, et,
4954 				      &depth, last_eb_bh, meta_ac);
4955 		if (ret) {
4956 			mlog_errno(ret);
4957 			goto out;
4958 		}
4959 	}
4960 
4961 	memset(&insert, 0, sizeof(struct ocfs2_insert_type));
4962 	insert.ins_appending = APPEND_NONE;
4963 	insert.ins_contig = CONTIG_NONE;
4964 	insert.ins_tree_depth = depth;
4965 
4966 	insert_range = le32_to_cpu(split_rec.e_cpos) +
4967 		le16_to_cpu(split_rec.e_leaf_clusters);
4968 	rec_range = le32_to_cpu(rec.e_cpos) +
4969 		le16_to_cpu(rec.e_leaf_clusters);
4970 
4971 	if (split_rec.e_cpos == rec.e_cpos) {
4972 		insert.ins_split = SPLIT_LEFT;
4973 	} else if (insert_range == rec_range) {
4974 		insert.ins_split = SPLIT_RIGHT;
4975 	} else {
4976 		/*
4977 		 * Left/right split. We fake this as a right split
4978 		 * first and then make a second pass as a left split.
4979 		 */
4980 		insert.ins_split = SPLIT_RIGHT;
4981 
4982 		ocfs2_make_right_split_rec(ocfs2_metadata_cache_get_super(et->et_ci),
4983 					   &tmprec, insert_range, &rec);
4984 
4985 		split_rec = tmprec;
4986 
4987 		BUG_ON(do_leftright);
4988 		do_leftright = 1;
4989 	}
4990 
4991 	ret = ocfs2_do_insert_extent(handle, et, &split_rec, &insert);
4992 	if (ret) {
4993 		mlog_errno(ret);
4994 		goto out;
4995 	}
4996 
4997 	if (do_leftright == 1) {
4998 		u32 cpos;
4999 		struct ocfs2_extent_list *el;
5000 
5001 		do_leftright++;
5002 		split_rec = *orig_split_rec;
5003 
5004 		ocfs2_reinit_path(path, 1);
5005 
5006 		cpos = le32_to_cpu(split_rec.e_cpos);
5007 		ret = ocfs2_find_path(et->et_ci, path, cpos);
5008 		if (ret) {
5009 			mlog_errno(ret);
5010 			goto out;
5011 		}
5012 
5013 		el = path_leaf_el(path);
5014 		split_index = ocfs2_search_extent_list(el, cpos);
5015 		if (split_index == -1) {
5016 			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5017 				    "Owner %llu has an extent at cpos %u which can no longer be found\n",
5018 				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5019 				    cpos);
5020 			ret = -EROFS;
5021 			goto out;
5022 		}
5023 		goto leftright;
5024 	}
5025 out:
5026 
5027 	return ret;
5028 }
5029 
ocfs2_replace_extent_rec(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,struct ocfs2_extent_list * el,int split_index,struct ocfs2_extent_rec * split_rec)5030 static int ocfs2_replace_extent_rec(handle_t *handle,
5031 				    struct ocfs2_extent_tree *et,
5032 				    struct ocfs2_path *path,
5033 				    struct ocfs2_extent_list *el,
5034 				    int split_index,
5035 				    struct ocfs2_extent_rec *split_rec)
5036 {
5037 	int ret;
5038 
5039 	ret = ocfs2_path_bh_journal_access(handle, et->et_ci, path,
5040 					   path_num_items(path) - 1);
5041 	if (ret) {
5042 		mlog_errno(ret);
5043 		goto out;
5044 	}
5045 
5046 	el->l_recs[split_index] = *split_rec;
5047 
5048 	ocfs2_journal_dirty(handle, path_leaf_bh(path));
5049 out:
5050 	return ret;
5051 }
5052 
5053 /*
5054  * Split part or all of the extent record at split_index in the leaf
5055  * pointed to by path. Merge with the contiguous extent record if needed.
5056  *
5057  * Care is taken to handle contiguousness so as to not grow the tree.
5058  *
5059  * meta_ac is not strictly necessary - we only truly need it if growth
5060  * of the tree is required. All other cases will degrade into a less
5061  * optimal tree layout.
5062  *
5063  * last_eb_bh should be the rightmost leaf block for any extent
5064  * btree. Since a split may grow the tree or a merge might shrink it,
5065  * the caller cannot trust the contents of that buffer after this call.
5066  *
5067  * This code is optimized for readability - several passes might be
5068  * made over certain portions of the tree. All of those blocks will
5069  * have been brought into cache (and pinned via the journal), so the
5070  * extra overhead is not expressed in terms of disk reads.
5071  */
ocfs2_split_extent(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,int split_index,struct ocfs2_extent_rec * split_rec,struct ocfs2_alloc_context * meta_ac,struct ocfs2_cached_dealloc_ctxt * dealloc)5072 int ocfs2_split_extent(handle_t *handle,
5073 		       struct ocfs2_extent_tree *et,
5074 		       struct ocfs2_path *path,
5075 		       int split_index,
5076 		       struct ocfs2_extent_rec *split_rec,
5077 		       struct ocfs2_alloc_context *meta_ac,
5078 		       struct ocfs2_cached_dealloc_ctxt *dealloc)
5079 {
5080 	int ret = 0;
5081 	struct ocfs2_extent_list *el = path_leaf_el(path);
5082 	struct buffer_head *last_eb_bh = NULL;
5083 	struct ocfs2_extent_rec *rec = &el->l_recs[split_index];
5084 	struct ocfs2_merge_ctxt ctxt;
5085 
5086 	if (le32_to_cpu(rec->e_cpos) > le32_to_cpu(split_rec->e_cpos) ||
5087 	    ((le32_to_cpu(rec->e_cpos) + le16_to_cpu(rec->e_leaf_clusters)) <
5088 	     (le32_to_cpu(split_rec->e_cpos) + le16_to_cpu(split_rec->e_leaf_clusters)))) {
5089 		ret = -EIO;
5090 		mlog_errno(ret);
5091 		goto out;
5092 	}
5093 
5094 	ret = ocfs2_figure_merge_contig_type(et, path, el,
5095 					     split_index,
5096 					     split_rec,
5097 					     &ctxt);
5098 	if (ret) {
5099 		mlog_errno(ret);
5100 		goto out;
5101 	}
5102 
5103 	/*
5104 	 * The core merge / split code wants to know how much room is
5105 	 * left in this allocation tree, so we pass the
5106 	 * rightmost extent list.
5107 	 */
5108 	if (path->p_tree_depth) {
5109 		struct ocfs2_extent_block *eb;
5110 
5111 		ret = ocfs2_read_extent_block(et->et_ci,
5112 					      ocfs2_et_get_last_eb_blk(et),
5113 					      &last_eb_bh);
5114 		if (ret) {
5115 			mlog_errno(ret);
5116 			goto out;
5117 		}
5118 
5119 		eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
5120 	}
5121 
5122 	if (rec->e_cpos == split_rec->e_cpos &&
5123 	    rec->e_leaf_clusters == split_rec->e_leaf_clusters)
5124 		ctxt.c_split_covers_rec = 1;
5125 	else
5126 		ctxt.c_split_covers_rec = 0;
5127 
5128 	ctxt.c_has_empty_extent = ocfs2_is_empty_extent(&el->l_recs[0]);
5129 
5130 	trace_ocfs2_split_extent(split_index, ctxt.c_contig_type,
5131 				 ctxt.c_has_empty_extent,
5132 				 ctxt.c_split_covers_rec);
5133 
5134 	if (ctxt.c_contig_type == CONTIG_NONE) {
5135 		if (ctxt.c_split_covers_rec)
5136 			ret = ocfs2_replace_extent_rec(handle, et, path, el,
5137 						       split_index, split_rec);
5138 		else
5139 			ret = ocfs2_split_and_insert(handle, et, path,
5140 						     &last_eb_bh, split_index,
5141 						     split_rec, meta_ac);
5142 		if (ret)
5143 			mlog_errno(ret);
5144 	} else {
5145 		ret = ocfs2_try_to_merge_extent(handle, et, path,
5146 						split_index, split_rec,
5147 						dealloc, &ctxt);
5148 		if (ret)
5149 			mlog_errno(ret);
5150 	}
5151 
5152 out:
5153 	brelse(last_eb_bh);
5154 	return ret;
5155 }
5156 
5157 /*
5158  * Change the flags of the already-existing extent at cpos for len clusters.
5159  *
5160  * new_flags: the flags we want to set.
5161  * clear_flags: the flags we want to clear.
5162  * phys: the new physical offset we want this new extent starts from.
5163  *
5164  * If the existing extent is larger than the request, initiate a
5165  * split. An attempt will be made at merging with adjacent extents.
5166  *
5167  * The caller is responsible for passing down meta_ac if we'll need it.
5168  */
ocfs2_change_extent_flag(handle_t * handle,struct ocfs2_extent_tree * et,u32 cpos,u32 len,u32 phys,struct ocfs2_alloc_context * meta_ac,struct ocfs2_cached_dealloc_ctxt * dealloc,int new_flags,int clear_flags)5169 int ocfs2_change_extent_flag(handle_t *handle,
5170 			     struct ocfs2_extent_tree *et,
5171 			     u32 cpos, u32 len, u32 phys,
5172 			     struct ocfs2_alloc_context *meta_ac,
5173 			     struct ocfs2_cached_dealloc_ctxt *dealloc,
5174 			     int new_flags, int clear_flags)
5175 {
5176 	int ret, index;
5177 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
5178 	u64 start_blkno = ocfs2_clusters_to_blocks(sb, phys);
5179 	struct ocfs2_extent_rec split_rec;
5180 	struct ocfs2_path *left_path = NULL;
5181 	struct ocfs2_extent_list *el;
5182 	struct ocfs2_extent_rec *rec;
5183 
5184 	left_path = ocfs2_new_path_from_et(et);
5185 	if (!left_path) {
5186 		ret = -ENOMEM;
5187 		mlog_errno(ret);
5188 		goto out;
5189 	}
5190 
5191 	ret = ocfs2_find_path(et->et_ci, left_path, cpos);
5192 	if (ret) {
5193 		mlog_errno(ret);
5194 		goto out;
5195 	}
5196 	el = path_leaf_el(left_path);
5197 
5198 	index = ocfs2_search_extent_list(el, cpos);
5199 	if (index == -1) {
5200 		ocfs2_error(sb,
5201 			    "Owner %llu has an extent at cpos %u which can no longer be found\n",
5202 			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5203 			    cpos);
5204 		ret = -EROFS;
5205 		goto out;
5206 	}
5207 
5208 	ret = -EIO;
5209 	rec = &el->l_recs[index];
5210 	if (new_flags && (rec->e_flags & new_flags)) {
5211 		mlog(ML_ERROR, "Owner %llu tried to set %d flags on an "
5212 		     "extent that already had them\n",
5213 		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5214 		     new_flags);
5215 		goto out;
5216 	}
5217 
5218 	if (clear_flags && !(rec->e_flags & clear_flags)) {
5219 		mlog(ML_ERROR, "Owner %llu tried to clear %d flags on an "
5220 		     "extent that didn't have them\n",
5221 		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5222 		     clear_flags);
5223 		goto out;
5224 	}
5225 
5226 	memset(&split_rec, 0, sizeof(struct ocfs2_extent_rec));
5227 	split_rec.e_cpos = cpu_to_le32(cpos);
5228 	split_rec.e_leaf_clusters = cpu_to_le16(len);
5229 	split_rec.e_blkno = cpu_to_le64(start_blkno);
5230 	split_rec.e_flags = rec->e_flags;
5231 	if (new_flags)
5232 		split_rec.e_flags |= new_flags;
5233 	if (clear_flags)
5234 		split_rec.e_flags &= ~clear_flags;
5235 
5236 	ret = ocfs2_split_extent(handle, et, left_path,
5237 				 index, &split_rec, meta_ac,
5238 				 dealloc);
5239 	if (ret)
5240 		mlog_errno(ret);
5241 
5242 out:
5243 	ocfs2_free_path(left_path);
5244 	return ret;
5245 
5246 }
5247 
5248 /*
5249  * Mark the already-existing extent at cpos as written for len clusters.
5250  * This removes the unwritten extent flag.
5251  *
5252  * If the existing extent is larger than the request, initiate a
5253  * split. An attempt will be made at merging with adjacent extents.
5254  *
5255  * The caller is responsible for passing down meta_ac if we'll need it.
5256  */
ocfs2_mark_extent_written(struct inode * inode,struct ocfs2_extent_tree * et,handle_t * handle,u32 cpos,u32 len,u32 phys,struct ocfs2_alloc_context * meta_ac,struct ocfs2_cached_dealloc_ctxt * dealloc)5257 int ocfs2_mark_extent_written(struct inode *inode,
5258 			      struct ocfs2_extent_tree *et,
5259 			      handle_t *handle, u32 cpos, u32 len, u32 phys,
5260 			      struct ocfs2_alloc_context *meta_ac,
5261 			      struct ocfs2_cached_dealloc_ctxt *dealloc)
5262 {
5263 	int ret;
5264 
5265 	trace_ocfs2_mark_extent_written(
5266 		(unsigned long long)OCFS2_I(inode)->ip_blkno,
5267 		cpos, len, phys);
5268 
5269 	if (!ocfs2_writes_unwritten_extents(OCFS2_SB(inode->i_sb))) {
5270 		ocfs2_error(inode->i_sb, "Inode %llu has unwritten extents that are being written to, but the feature bit is not set in the super block\n",
5271 			    (unsigned long long)OCFS2_I(inode)->ip_blkno);
5272 		ret = -EROFS;
5273 		goto out;
5274 	}
5275 
5276 	/*
5277 	 * XXX: This should be fixed up so that we just re-insert the
5278 	 * next extent records.
5279 	 */
5280 	ocfs2_et_extent_map_truncate(et, 0);
5281 
5282 	ret = ocfs2_change_extent_flag(handle, et, cpos,
5283 				       len, phys, meta_ac, dealloc,
5284 				       0, OCFS2_EXT_UNWRITTEN);
5285 	if (ret)
5286 		mlog_errno(ret);
5287 
5288 out:
5289 	return ret;
5290 }
5291 
ocfs2_split_tree(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,int index,u32 new_range,struct ocfs2_alloc_context * meta_ac)5292 static int ocfs2_split_tree(handle_t *handle, struct ocfs2_extent_tree *et,
5293 			    struct ocfs2_path *path,
5294 			    int index, u32 new_range,
5295 			    struct ocfs2_alloc_context *meta_ac)
5296 {
5297 	int ret, depth, credits;
5298 	struct buffer_head *last_eb_bh = NULL;
5299 	struct ocfs2_extent_block *eb;
5300 	struct ocfs2_extent_list *rightmost_el, *el;
5301 	struct ocfs2_extent_rec split_rec;
5302 	struct ocfs2_extent_rec *rec;
5303 	struct ocfs2_insert_type insert;
5304 
5305 	/*
5306 	 * Setup the record to split before we grow the tree.
5307 	 */
5308 	el = path_leaf_el(path);
5309 	rec = &el->l_recs[index];
5310 	ocfs2_make_right_split_rec(ocfs2_metadata_cache_get_super(et->et_ci),
5311 				   &split_rec, new_range, rec);
5312 
5313 	depth = path->p_tree_depth;
5314 	if (depth > 0) {
5315 		ret = ocfs2_read_extent_block(et->et_ci,
5316 					      ocfs2_et_get_last_eb_blk(et),
5317 					      &last_eb_bh);
5318 		if (ret < 0) {
5319 			mlog_errno(ret);
5320 			goto out;
5321 		}
5322 
5323 		eb = (struct ocfs2_extent_block *) last_eb_bh->b_data;
5324 		rightmost_el = &eb->h_list;
5325 	} else
5326 		rightmost_el = path_leaf_el(path);
5327 
5328 	credits = path->p_tree_depth +
5329 		  ocfs2_extend_meta_needed(et->et_root_el);
5330 	ret = ocfs2_extend_trans(handle, credits);
5331 	if (ret) {
5332 		mlog_errno(ret);
5333 		goto out;
5334 	}
5335 
5336 	if (le16_to_cpu(rightmost_el->l_next_free_rec) ==
5337 	    le16_to_cpu(rightmost_el->l_count)) {
5338 		ret = ocfs2_grow_tree(handle, et, &depth, &last_eb_bh,
5339 				      meta_ac);
5340 		if (ret) {
5341 			mlog_errno(ret);
5342 			goto out;
5343 		}
5344 	}
5345 
5346 	memset(&insert, 0, sizeof(struct ocfs2_insert_type));
5347 	insert.ins_appending = APPEND_NONE;
5348 	insert.ins_contig = CONTIG_NONE;
5349 	insert.ins_split = SPLIT_RIGHT;
5350 	insert.ins_tree_depth = depth;
5351 
5352 	ret = ocfs2_do_insert_extent(handle, et, &split_rec, &insert);
5353 	if (ret)
5354 		mlog_errno(ret);
5355 
5356 out:
5357 	brelse(last_eb_bh);
5358 	return ret;
5359 }
5360 
ocfs2_truncate_rec(handle_t * handle,struct ocfs2_extent_tree * et,struct ocfs2_path * path,int index,struct ocfs2_cached_dealloc_ctxt * dealloc,u32 cpos,u32 len)5361 static int ocfs2_truncate_rec(handle_t *handle,
5362 			      struct ocfs2_extent_tree *et,
5363 			      struct ocfs2_path *path, int index,
5364 			      struct ocfs2_cached_dealloc_ctxt *dealloc,
5365 			      u32 cpos, u32 len)
5366 {
5367 	int ret;
5368 	u32 left_cpos, rec_range, trunc_range;
5369 	int is_rightmost_tree_rec = 0;
5370 	struct super_block *sb = ocfs2_metadata_cache_get_super(et->et_ci);
5371 	struct ocfs2_path *left_path = NULL;
5372 	struct ocfs2_extent_list *el = path_leaf_el(path);
5373 	struct ocfs2_extent_rec *rec;
5374 	struct ocfs2_extent_block *eb;
5375 
5376 	if (ocfs2_is_empty_extent(&el->l_recs[0]) && index > 0) {
5377 		/* extend credit for ocfs2_remove_rightmost_path */
5378 		ret = ocfs2_extend_rotate_transaction(handle, 0,
5379 				handle->h_buffer_credits,
5380 				path);
5381 		if (ret) {
5382 			mlog_errno(ret);
5383 			goto out;
5384 		}
5385 
5386 		ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
5387 		if (ret) {
5388 			mlog_errno(ret);
5389 			goto out;
5390 		}
5391 
5392 		index--;
5393 	}
5394 
5395 	if (index == (le16_to_cpu(el->l_next_free_rec) - 1) &&
5396 	    path->p_tree_depth) {
5397 		/*
5398 		 * Check whether this is the rightmost tree record. If
5399 		 * we remove all of this record or part of its right
5400 		 * edge then an update of the record lengths above it
5401 		 * will be required.
5402 		 */
5403 		eb = (struct ocfs2_extent_block *)path_leaf_bh(path)->b_data;
5404 		if (eb->h_next_leaf_blk == 0)
5405 			is_rightmost_tree_rec = 1;
5406 	}
5407 
5408 	rec = &el->l_recs[index];
5409 	if (index == 0 && path->p_tree_depth &&
5410 	    le32_to_cpu(rec->e_cpos) == cpos) {
5411 		/*
5412 		 * Changing the leftmost offset (via partial or whole
5413 		 * record truncate) of an interior (or rightmost) path
5414 		 * means we have to update the subtree that is formed
5415 		 * by this leaf and the one to it's left.
5416 		 *
5417 		 * There are two cases we can skip:
5418 		 *   1) Path is the leftmost one in our btree.
5419 		 *   2) The leaf is rightmost and will be empty after
5420 		 *      we remove the extent record - the rotate code
5421 		 *      knows how to update the newly formed edge.
5422 		 */
5423 
5424 		ret = ocfs2_find_cpos_for_left_leaf(sb, path, &left_cpos);
5425 		if (ret) {
5426 			mlog_errno(ret);
5427 			goto out;
5428 		}
5429 
5430 		if (left_cpos && le16_to_cpu(el->l_next_free_rec) > 1) {
5431 			left_path = ocfs2_new_path_from_path(path);
5432 			if (!left_path) {
5433 				ret = -ENOMEM;
5434 				mlog_errno(ret);
5435 				goto out;
5436 			}
5437 
5438 			ret = ocfs2_find_path(et->et_ci, left_path,
5439 					      left_cpos);
5440 			if (ret) {
5441 				mlog_errno(ret);
5442 				goto out;
5443 			}
5444 		}
5445 	}
5446 
5447 	ret = ocfs2_extend_rotate_transaction(handle, 0,
5448 					      handle->h_buffer_credits,
5449 					      path);
5450 	if (ret) {
5451 		mlog_errno(ret);
5452 		goto out;
5453 	}
5454 
5455 	ret = ocfs2_journal_access_path(et->et_ci, handle, path);
5456 	if (ret) {
5457 		mlog_errno(ret);
5458 		goto out;
5459 	}
5460 
5461 	ret = ocfs2_journal_access_path(et->et_ci, handle, left_path);
5462 	if (ret) {
5463 		mlog_errno(ret);
5464 		goto out;
5465 	}
5466 
5467 	rec_range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
5468 	trunc_range = cpos + len;
5469 
5470 	if (le32_to_cpu(rec->e_cpos) == cpos && rec_range == trunc_range) {
5471 		int next_free;
5472 
5473 		memset(rec, 0, sizeof(*rec));
5474 		ocfs2_cleanup_merge(el, index);
5475 
5476 		next_free = le16_to_cpu(el->l_next_free_rec);
5477 		if (is_rightmost_tree_rec && next_free > 1) {
5478 			/*
5479 			 * We skip the edge update if this path will
5480 			 * be deleted by the rotate code.
5481 			 */
5482 			rec = &el->l_recs[next_free - 1];
5483 			ocfs2_adjust_rightmost_records(handle, et, path,
5484 						       rec);
5485 		}
5486 	} else if (le32_to_cpu(rec->e_cpos) == cpos) {
5487 		/* Remove leftmost portion of the record. */
5488 		le32_add_cpu(&rec->e_cpos, len);
5489 		le64_add_cpu(&rec->e_blkno, ocfs2_clusters_to_blocks(sb, len));
5490 		le16_add_cpu(&rec->e_leaf_clusters, -len);
5491 	} else if (rec_range == trunc_range) {
5492 		/* Remove rightmost portion of the record */
5493 		le16_add_cpu(&rec->e_leaf_clusters, -len);
5494 		if (is_rightmost_tree_rec)
5495 			ocfs2_adjust_rightmost_records(handle, et, path, rec);
5496 	} else {
5497 		/* Caller should have trapped this. */
5498 		mlog(ML_ERROR, "Owner %llu: Invalid record truncate: (%u, %u) "
5499 		     "(%u, %u)\n",
5500 		     (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5501 		     le32_to_cpu(rec->e_cpos),
5502 		     le16_to_cpu(rec->e_leaf_clusters), cpos, len);
5503 		BUG();
5504 	}
5505 
5506 	if (left_path) {
5507 		int subtree_index;
5508 
5509 		subtree_index = ocfs2_find_subtree_root(et, left_path, path);
5510 		ocfs2_complete_edge_insert(handle, left_path, path,
5511 					   subtree_index);
5512 	}
5513 
5514 	ocfs2_journal_dirty(handle, path_leaf_bh(path));
5515 
5516 	ret = ocfs2_rotate_tree_left(handle, et, path, dealloc);
5517 	if (ret)
5518 		mlog_errno(ret);
5519 
5520 out:
5521 	ocfs2_free_path(left_path);
5522 	return ret;
5523 }
5524 
ocfs2_remove_extent(handle_t * handle,struct ocfs2_extent_tree * et,u32 cpos,u32 len,struct ocfs2_alloc_context * meta_ac,struct ocfs2_cached_dealloc_ctxt * dealloc)5525 int ocfs2_remove_extent(handle_t *handle,
5526 			struct ocfs2_extent_tree *et,
5527 			u32 cpos, u32 len,
5528 			struct ocfs2_alloc_context *meta_ac,
5529 			struct ocfs2_cached_dealloc_ctxt *dealloc)
5530 {
5531 	int ret, index;
5532 	u32 rec_range, trunc_range;
5533 	struct ocfs2_extent_rec *rec;
5534 	struct ocfs2_extent_list *el;
5535 	struct ocfs2_path *path = NULL;
5536 
5537 	/*
5538 	 * XXX: Why are we truncating to 0 instead of wherever this
5539 	 * affects us?
5540 	 */
5541 	ocfs2_et_extent_map_truncate(et, 0);
5542 
5543 	path = ocfs2_new_path_from_et(et);
5544 	if (!path) {
5545 		ret = -ENOMEM;
5546 		mlog_errno(ret);
5547 		goto out;
5548 	}
5549 
5550 	ret = ocfs2_find_path(et->et_ci, path, cpos);
5551 	if (ret) {
5552 		mlog_errno(ret);
5553 		goto out;
5554 	}
5555 
5556 	el = path_leaf_el(path);
5557 	index = ocfs2_search_extent_list(el, cpos);
5558 	if (index == -1) {
5559 		ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5560 			    "Owner %llu has an extent at cpos %u which can no longer be found\n",
5561 			    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5562 			    cpos);
5563 		ret = -EROFS;
5564 		goto out;
5565 	}
5566 
5567 	/*
5568 	 * We have 3 cases of extent removal:
5569 	 *   1) Range covers the entire extent rec
5570 	 *   2) Range begins or ends on one edge of the extent rec
5571 	 *   3) Range is in the middle of the extent rec (no shared edges)
5572 	 *
5573 	 * For case 1 we remove the extent rec and left rotate to
5574 	 * fill the hole.
5575 	 *
5576 	 * For case 2 we just shrink the existing extent rec, with a
5577 	 * tree update if the shrinking edge is also the edge of an
5578 	 * extent block.
5579 	 *
5580 	 * For case 3 we do a right split to turn the extent rec into
5581 	 * something case 2 can handle.
5582 	 */
5583 	rec = &el->l_recs[index];
5584 	rec_range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
5585 	trunc_range = cpos + len;
5586 
5587 	BUG_ON(cpos < le32_to_cpu(rec->e_cpos) || trunc_range > rec_range);
5588 
5589 	trace_ocfs2_remove_extent(
5590 		(unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5591 		cpos, len, index, le32_to_cpu(rec->e_cpos),
5592 		ocfs2_rec_clusters(el, rec));
5593 
5594 	if (le32_to_cpu(rec->e_cpos) == cpos || rec_range == trunc_range) {
5595 		ret = ocfs2_truncate_rec(handle, et, path, index, dealloc,
5596 					 cpos, len);
5597 		if (ret) {
5598 			mlog_errno(ret);
5599 			goto out;
5600 		}
5601 	} else {
5602 		ret = ocfs2_split_tree(handle, et, path, index,
5603 				       trunc_range, meta_ac);
5604 		if (ret) {
5605 			mlog_errno(ret);
5606 			goto out;
5607 		}
5608 
5609 		/*
5610 		 * The split could have manipulated the tree enough to
5611 		 * move the record location, so we have to look for it again.
5612 		 */
5613 		ocfs2_reinit_path(path, 1);
5614 
5615 		ret = ocfs2_find_path(et->et_ci, path, cpos);
5616 		if (ret) {
5617 			mlog_errno(ret);
5618 			goto out;
5619 		}
5620 
5621 		el = path_leaf_el(path);
5622 		index = ocfs2_search_extent_list(el, cpos);
5623 		if (index == -1) {
5624 			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5625 				    "Owner %llu: split at cpos %u lost record\n",
5626 				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5627 				    cpos);
5628 			ret = -EROFS;
5629 			goto out;
5630 		}
5631 
5632 		/*
5633 		 * Double check our values here. If anything is fishy,
5634 		 * it's easier to catch it at the top level.
5635 		 */
5636 		rec = &el->l_recs[index];
5637 		rec_range = le32_to_cpu(rec->e_cpos) +
5638 			ocfs2_rec_clusters(el, rec);
5639 		if (rec_range != trunc_range) {
5640 			ocfs2_error(ocfs2_metadata_cache_get_super(et->et_ci),
5641 				    "Owner %llu: error after split at cpos %u trunc len %u, existing record is (%u,%u)\n",
5642 				    (unsigned long long)ocfs2_metadata_cache_owner(et->et_ci),
5643 				    cpos, len, le32_to_cpu(rec->e_cpos),
5644 				    ocfs2_rec_clusters(el, rec));
5645 			ret = -EROFS;
5646 			goto out;
5647 		}
5648 
5649 		ret = ocfs2_truncate_rec(handle, et, path, index, dealloc,
5650 					 cpos, len);
5651 		if (ret)
5652 			mlog_errno(ret);
5653 	}
5654 
5655 out:
5656 	ocfs2_free_path(path);
5657 	return ret;
5658 }
5659 
5660 /*
5661  * ocfs2_reserve_blocks_for_rec_trunc() would look basically the
5662  * same as ocfs2_lock_alloctors(), except for it accepts a blocks
5663  * number to reserve some extra blocks, and it only handles meta
5664  * data allocations.
5665  *
5666  * Currently, only ocfs2_remove_btree_range() uses it for truncating
5667  * and punching holes.
5668  */
ocfs2_reserve_blocks_for_rec_trunc(struct inode * inode,struct ocfs2_extent_tree * et,u32 extents_to_split,struct ocfs2_alloc_context ** ac,int extra_blocks)5669 static int ocfs2_reserve_blocks_for_rec_trunc(struct inode *inode,
5670 					      struct ocfs2_extent_tree *et,
5671 					      u32 extents_to_split,
5672 					      struct ocfs2_alloc_context **ac,
5673 					      int extra_blocks)
5674 {
5675 	int ret = 0, num_free_extents;
5676 	unsigned int max_recs_needed = 2 * extents_to_split;
5677 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
5678 
5679 	*ac = NULL;
5680 
5681 	num_free_extents = ocfs2_num_free_extents(et);
5682 	if (num_free_extents < 0) {
5683 		ret = num_free_extents;
5684 		mlog_errno(ret);
5685 		goto out;
5686 	}
5687 
5688 	if (!num_free_extents ||
5689 	    (ocfs2_sparse_alloc(osb) && num_free_extents < max_recs_needed))
5690 		extra_blocks += ocfs2_extend_meta_needed(et->et_root_el);
5691 
5692 	if (extra_blocks) {
5693 		ret = ocfs2_reserve_new_metadata_blocks(osb, extra_blocks, ac);
5694 		if (ret < 0) {
5695 			if (ret != -ENOSPC)
5696 				mlog_errno(ret);
5697 		}
5698 	}
5699 
5700 out:
5701 	if (ret) {
5702 		if (*ac) {
5703 			ocfs2_free_alloc_context(*ac);
5704 			*ac = NULL;
5705 		}
5706 	}
5707 
5708 	return ret;
5709 }
5710 
ocfs2_remove_btree_range(struct inode * inode,struct ocfs2_extent_tree * et,u32 cpos,u32 phys_cpos,u32 len,int flags,struct ocfs2_cached_dealloc_ctxt * dealloc,u64 refcount_loc,bool refcount_tree_locked)5711 int ocfs2_remove_btree_range(struct inode *inode,
5712 			     struct ocfs2_extent_tree *et,
5713 			     u32 cpos, u32 phys_cpos, u32 len, int flags,
5714 			     struct ocfs2_cached_dealloc_ctxt *dealloc,
5715 			     u64 refcount_loc, bool refcount_tree_locked)
5716 {
5717 	int ret, credits = 0, extra_blocks = 0;
5718 	u64 phys_blkno = ocfs2_clusters_to_blocks(inode->i_sb, phys_cpos);
5719 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
5720 	struct inode *tl_inode = osb->osb_tl_inode;
5721 	handle_t *handle;
5722 	struct ocfs2_alloc_context *meta_ac = NULL;
5723 	struct ocfs2_refcount_tree *ref_tree = NULL;
5724 
5725 	if ((flags & OCFS2_EXT_REFCOUNTED) && len) {
5726 		BUG_ON(!ocfs2_is_refcount_inode(inode));
5727 
5728 		if (!refcount_tree_locked) {
5729 			ret = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
5730 						       &ref_tree, NULL);
5731 			if (ret) {
5732 				mlog_errno(ret);
5733 				goto bail;
5734 			}
5735 		}
5736 
5737 		ret = ocfs2_prepare_refcount_change_for_del(inode,
5738 							    refcount_loc,
5739 							    phys_blkno,
5740 							    len,
5741 							    &credits,
5742 							    &extra_blocks);
5743 		if (ret < 0) {
5744 			mlog_errno(ret);
5745 			goto bail;
5746 		}
5747 	}
5748 
5749 	ret = ocfs2_reserve_blocks_for_rec_trunc(inode, et, 1, &meta_ac,
5750 						 extra_blocks);
5751 	if (ret) {
5752 		mlog_errno(ret);
5753 		goto bail;
5754 	}
5755 
5756 	inode_lock(tl_inode);
5757 
5758 	if (ocfs2_truncate_log_needs_flush(osb)) {
5759 		ret = __ocfs2_flush_truncate_log(osb);
5760 		if (ret < 0) {
5761 			mlog_errno(ret);
5762 			goto out;
5763 		}
5764 	}
5765 
5766 	handle = ocfs2_start_trans(osb,
5767 			ocfs2_remove_extent_credits(osb->sb) + credits);
5768 	if (IS_ERR(handle)) {
5769 		ret = PTR_ERR(handle);
5770 		mlog_errno(ret);
5771 		goto out;
5772 	}
5773 
5774 	ret = ocfs2_et_root_journal_access(handle, et,
5775 					   OCFS2_JOURNAL_ACCESS_WRITE);
5776 	if (ret) {
5777 		mlog_errno(ret);
5778 		goto out_commit;
5779 	}
5780 
5781 	dquot_free_space_nodirty(inode,
5782 				  ocfs2_clusters_to_bytes(inode->i_sb, len));
5783 
5784 	ret = ocfs2_remove_extent(handle, et, cpos, len, meta_ac, dealloc);
5785 	if (ret) {
5786 		mlog_errno(ret);
5787 		goto out_commit;
5788 	}
5789 
5790 	ocfs2_et_update_clusters(et, -len);
5791 	ocfs2_update_inode_fsync_trans(handle, inode, 1);
5792 
5793 	ocfs2_journal_dirty(handle, et->et_root_bh);
5794 
5795 	if (phys_blkno) {
5796 		if (flags & OCFS2_EXT_REFCOUNTED)
5797 			ret = ocfs2_decrease_refcount(inode, handle,
5798 					ocfs2_blocks_to_clusters(osb->sb,
5799 								 phys_blkno),
5800 					len, meta_ac,
5801 					dealloc, 1);
5802 		else
5803 			ret = ocfs2_truncate_log_append(osb, handle,
5804 							phys_blkno, len);
5805 		if (ret)
5806 			mlog_errno(ret);
5807 
5808 	}
5809 
5810 out_commit:
5811 	ocfs2_commit_trans(osb, handle);
5812 out:
5813 	inode_unlock(tl_inode);
5814 bail:
5815 	if (meta_ac)
5816 		ocfs2_free_alloc_context(meta_ac);
5817 
5818 	if (ref_tree)
5819 		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
5820 
5821 	return ret;
5822 }
5823 
ocfs2_truncate_log_needs_flush(struct ocfs2_super * osb)5824 int ocfs2_truncate_log_needs_flush(struct ocfs2_super *osb)
5825 {
5826 	struct buffer_head *tl_bh = osb->osb_tl_bh;
5827 	struct ocfs2_dinode *di;
5828 	struct ocfs2_truncate_log *tl;
5829 
5830 	di = (struct ocfs2_dinode *) tl_bh->b_data;
5831 	tl = &di->id2.i_dealloc;
5832 
5833 	mlog_bug_on_msg(le16_to_cpu(tl->tl_used) > le16_to_cpu(tl->tl_count),
5834 			"slot %d, invalid truncate log parameters: used = "
5835 			"%u, count = %u\n", osb->slot_num,
5836 			le16_to_cpu(tl->tl_used), le16_to_cpu(tl->tl_count));
5837 	return le16_to_cpu(tl->tl_used) == le16_to_cpu(tl->tl_count);
5838 }
5839 
ocfs2_truncate_log_can_coalesce(struct ocfs2_truncate_log * tl,unsigned int new_start)5840 static int ocfs2_truncate_log_can_coalesce(struct ocfs2_truncate_log *tl,
5841 					   unsigned int new_start)
5842 {
5843 	unsigned int tail_index;
5844 	unsigned int current_tail;
5845 
5846 	/* No records, nothing to coalesce */
5847 	if (!le16_to_cpu(tl->tl_used))
5848 		return 0;
5849 
5850 	tail_index = le16_to_cpu(tl->tl_used) - 1;
5851 	current_tail = le32_to_cpu(tl->tl_recs[tail_index].t_start);
5852 	current_tail += le32_to_cpu(tl->tl_recs[tail_index].t_clusters);
5853 
5854 	return current_tail == new_start;
5855 }
5856 
ocfs2_truncate_log_append(struct ocfs2_super * osb,handle_t * handle,u64 start_blk,unsigned int num_clusters)5857 int ocfs2_truncate_log_append(struct ocfs2_super *osb,
5858 			      handle_t *handle,
5859 			      u64 start_blk,
5860 			      unsigned int num_clusters)
5861 {
5862 	int status, index;
5863 	unsigned int start_cluster, tl_count;
5864 	struct inode *tl_inode = osb->osb_tl_inode;
5865 	struct buffer_head *tl_bh = osb->osb_tl_bh;
5866 	struct ocfs2_dinode *di;
5867 	struct ocfs2_truncate_log *tl;
5868 
5869 	BUG_ON(inode_trylock(tl_inode));
5870 
5871 	start_cluster = ocfs2_blocks_to_clusters(osb->sb, start_blk);
5872 
5873 	di = (struct ocfs2_dinode *) tl_bh->b_data;
5874 
5875 	/* tl_bh is loaded from ocfs2_truncate_log_init().  It's validated
5876 	 * by the underlying call to ocfs2_read_inode_block(), so any
5877 	 * corruption is a code bug */
5878 	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
5879 
5880 	tl = &di->id2.i_dealloc;
5881 	tl_count = le16_to_cpu(tl->tl_count);
5882 	mlog_bug_on_msg(tl_count > ocfs2_truncate_recs_per_inode(osb->sb) ||
5883 			tl_count == 0,
5884 			"Truncate record count on #%llu invalid "
5885 			"wanted %u, actual %u\n",
5886 			(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5887 			ocfs2_truncate_recs_per_inode(osb->sb),
5888 			le16_to_cpu(tl->tl_count));
5889 
5890 	/* Caller should have known to flush before calling us. */
5891 	index = le16_to_cpu(tl->tl_used);
5892 	if (index >= tl_count) {
5893 		status = -ENOSPC;
5894 		mlog_errno(status);
5895 		goto bail;
5896 	}
5897 
5898 	status = ocfs2_journal_access_di(handle, INODE_CACHE(tl_inode), tl_bh,
5899 					 OCFS2_JOURNAL_ACCESS_WRITE);
5900 	if (status < 0) {
5901 		mlog_errno(status);
5902 		goto bail;
5903 	}
5904 
5905 	trace_ocfs2_truncate_log_append(
5906 		(unsigned long long)OCFS2_I(tl_inode)->ip_blkno, index,
5907 		start_cluster, num_clusters);
5908 	if (ocfs2_truncate_log_can_coalesce(tl, start_cluster)) {
5909 		/*
5910 		 * Move index back to the record we are coalescing with.
5911 		 * ocfs2_truncate_log_can_coalesce() guarantees nonzero
5912 		 */
5913 		index--;
5914 
5915 		num_clusters += le32_to_cpu(tl->tl_recs[index].t_clusters);
5916 		trace_ocfs2_truncate_log_append(
5917 			(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5918 			index, le32_to_cpu(tl->tl_recs[index].t_start),
5919 			num_clusters);
5920 	} else {
5921 		tl->tl_recs[index].t_start = cpu_to_le32(start_cluster);
5922 		tl->tl_used = cpu_to_le16(index + 1);
5923 	}
5924 	tl->tl_recs[index].t_clusters = cpu_to_le32(num_clusters);
5925 
5926 	ocfs2_journal_dirty(handle, tl_bh);
5927 
5928 	osb->truncated_clusters += num_clusters;
5929 bail:
5930 	return status;
5931 }
5932 
ocfs2_replay_truncate_records(struct ocfs2_super * osb,struct inode * data_alloc_inode,struct buffer_head * data_alloc_bh)5933 static int ocfs2_replay_truncate_records(struct ocfs2_super *osb,
5934 					 struct inode *data_alloc_inode,
5935 					 struct buffer_head *data_alloc_bh)
5936 {
5937 	int status = 0;
5938 	int i;
5939 	unsigned int num_clusters;
5940 	u64 start_blk;
5941 	struct ocfs2_truncate_rec rec;
5942 	struct ocfs2_dinode *di;
5943 	struct ocfs2_truncate_log *tl;
5944 	struct inode *tl_inode = osb->osb_tl_inode;
5945 	struct buffer_head *tl_bh = osb->osb_tl_bh;
5946 	handle_t *handle;
5947 
5948 	di = (struct ocfs2_dinode *) tl_bh->b_data;
5949 	tl = &di->id2.i_dealloc;
5950 	i = le16_to_cpu(tl->tl_used) - 1;
5951 	while (i >= 0) {
5952 		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_FLUSH_ONE_REC);
5953 		if (IS_ERR(handle)) {
5954 			status = PTR_ERR(handle);
5955 			mlog_errno(status);
5956 			goto bail;
5957 		}
5958 
5959 		/* Caller has given us at least enough credits to
5960 		 * update the truncate log dinode */
5961 		status = ocfs2_journal_access_di(handle, INODE_CACHE(tl_inode), tl_bh,
5962 						 OCFS2_JOURNAL_ACCESS_WRITE);
5963 		if (status < 0) {
5964 			mlog_errno(status);
5965 			goto bail;
5966 		}
5967 
5968 		tl->tl_used = cpu_to_le16(i);
5969 
5970 		ocfs2_journal_dirty(handle, tl_bh);
5971 
5972 		rec = tl->tl_recs[i];
5973 		start_blk = ocfs2_clusters_to_blocks(data_alloc_inode->i_sb,
5974 						    le32_to_cpu(rec.t_start));
5975 		num_clusters = le32_to_cpu(rec.t_clusters);
5976 
5977 		/* if start_blk is not set, we ignore the record as
5978 		 * invalid. */
5979 		if (start_blk) {
5980 			trace_ocfs2_replay_truncate_records(
5981 				(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
5982 				i, le32_to_cpu(rec.t_start), num_clusters);
5983 
5984 			status = ocfs2_free_clusters(handle, data_alloc_inode,
5985 						     data_alloc_bh, start_blk,
5986 						     num_clusters);
5987 			if (status < 0) {
5988 				mlog_errno(status);
5989 				goto bail;
5990 			}
5991 		}
5992 
5993 		ocfs2_commit_trans(osb, handle);
5994 		i--;
5995 	}
5996 
5997 	osb->truncated_clusters = 0;
5998 
5999 bail:
6000 	return status;
6001 }
6002 
6003 /* Expects you to already be holding tl_inode->i_mutex */
__ocfs2_flush_truncate_log(struct ocfs2_super * osb)6004 int __ocfs2_flush_truncate_log(struct ocfs2_super *osb)
6005 {
6006 	int status;
6007 	unsigned int num_to_flush;
6008 	struct inode *tl_inode = osb->osb_tl_inode;
6009 	struct inode *data_alloc_inode = NULL;
6010 	struct buffer_head *tl_bh = osb->osb_tl_bh;
6011 	struct buffer_head *data_alloc_bh = NULL;
6012 	struct ocfs2_dinode *di;
6013 	struct ocfs2_truncate_log *tl;
6014 
6015 	BUG_ON(inode_trylock(tl_inode));
6016 
6017 	di = (struct ocfs2_dinode *) tl_bh->b_data;
6018 
6019 	/* tl_bh is loaded from ocfs2_truncate_log_init().  It's validated
6020 	 * by the underlying call to ocfs2_read_inode_block(), so any
6021 	 * corruption is a code bug */
6022 	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
6023 
6024 	tl = &di->id2.i_dealloc;
6025 	num_to_flush = le16_to_cpu(tl->tl_used);
6026 	trace_ocfs2_flush_truncate_log(
6027 		(unsigned long long)OCFS2_I(tl_inode)->ip_blkno,
6028 		num_to_flush);
6029 	if (!num_to_flush) {
6030 		status = 0;
6031 		goto out;
6032 	}
6033 
6034 	data_alloc_inode = ocfs2_get_system_file_inode(osb,
6035 						       GLOBAL_BITMAP_SYSTEM_INODE,
6036 						       OCFS2_INVALID_SLOT);
6037 	if (!data_alloc_inode) {
6038 		status = -EINVAL;
6039 		mlog(ML_ERROR, "Could not get bitmap inode!\n");
6040 		goto out;
6041 	}
6042 
6043 	inode_lock(data_alloc_inode);
6044 
6045 	status = ocfs2_inode_lock(data_alloc_inode, &data_alloc_bh, 1);
6046 	if (status < 0) {
6047 		mlog_errno(status);
6048 		goto out_mutex;
6049 	}
6050 
6051 	status = ocfs2_replay_truncate_records(osb, data_alloc_inode,
6052 					       data_alloc_bh);
6053 	if (status < 0)
6054 		mlog_errno(status);
6055 
6056 	brelse(data_alloc_bh);
6057 	ocfs2_inode_unlock(data_alloc_inode, 1);
6058 
6059 out_mutex:
6060 	inode_unlock(data_alloc_inode);
6061 	iput(data_alloc_inode);
6062 
6063 out:
6064 	return status;
6065 }
6066 
ocfs2_flush_truncate_log(struct ocfs2_super * osb)6067 int ocfs2_flush_truncate_log(struct ocfs2_super *osb)
6068 {
6069 	int status;
6070 	struct inode *tl_inode = osb->osb_tl_inode;
6071 
6072 	inode_lock(tl_inode);
6073 	status = __ocfs2_flush_truncate_log(osb);
6074 	inode_unlock(tl_inode);
6075 
6076 	return status;
6077 }
6078 
ocfs2_truncate_log_worker(struct work_struct * work)6079 static void ocfs2_truncate_log_worker(struct work_struct *work)
6080 {
6081 	int status;
6082 	struct ocfs2_super *osb =
6083 		container_of(work, struct ocfs2_super,
6084 			     osb_truncate_log_wq.work);
6085 
6086 	status = ocfs2_flush_truncate_log(osb);
6087 	if (status < 0)
6088 		mlog_errno(status);
6089 	else
6090 		ocfs2_init_steal_slots(osb);
6091 }
6092 
6093 #define OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL (2 * HZ)
ocfs2_schedule_truncate_log_flush(struct ocfs2_super * osb,int cancel)6094 void ocfs2_schedule_truncate_log_flush(struct ocfs2_super *osb,
6095 				       int cancel)
6096 {
6097 	if (osb->osb_tl_inode &&
6098 			atomic_read(&osb->osb_tl_disable) == 0) {
6099 		/* We want to push off log flushes while truncates are
6100 		 * still running. */
6101 		if (cancel)
6102 			cancel_delayed_work(&osb->osb_truncate_log_wq);
6103 
6104 		queue_delayed_work(osb->ocfs2_wq, &osb->osb_truncate_log_wq,
6105 				   OCFS2_TRUNCATE_LOG_FLUSH_INTERVAL);
6106 	}
6107 }
6108 
6109 /*
6110  * Try to flush truncate logs if we can free enough clusters from it.
6111  * As for return value, "< 0" means error, "0" no space and "1" means
6112  * we have freed enough spaces and let the caller try to allocate again.
6113  */
ocfs2_try_to_free_truncate_log(struct ocfs2_super * osb,unsigned int needed)6114 int ocfs2_try_to_free_truncate_log(struct ocfs2_super *osb,
6115 					unsigned int needed)
6116 {
6117 	tid_t target;
6118 	int ret = 0;
6119 	unsigned int truncated_clusters;
6120 
6121 	inode_lock(osb->osb_tl_inode);
6122 	truncated_clusters = osb->truncated_clusters;
6123 	inode_unlock(osb->osb_tl_inode);
6124 
6125 	/*
6126 	 * Check whether we can succeed in allocating if we free
6127 	 * the truncate log.
6128 	 */
6129 	if (truncated_clusters < needed)
6130 		goto out;
6131 
6132 	ret = ocfs2_flush_truncate_log(osb);
6133 	if (ret) {
6134 		mlog_errno(ret);
6135 		goto out;
6136 	}
6137 
6138 	if (jbd2_journal_start_commit(osb->journal->j_journal, &target)) {
6139 		jbd2_log_wait_commit(osb->journal->j_journal, target);
6140 		ret = 1;
6141 	}
6142 out:
6143 	return ret;
6144 }
6145 
ocfs2_get_truncate_log_info(struct ocfs2_super * osb,int slot_num,struct inode ** tl_inode,struct buffer_head ** tl_bh)6146 static int ocfs2_get_truncate_log_info(struct ocfs2_super *osb,
6147 				       int slot_num,
6148 				       struct inode **tl_inode,
6149 				       struct buffer_head **tl_bh)
6150 {
6151 	int status;
6152 	struct inode *inode = NULL;
6153 	struct buffer_head *bh = NULL;
6154 
6155 	inode = ocfs2_get_system_file_inode(osb,
6156 					   TRUNCATE_LOG_SYSTEM_INODE,
6157 					   slot_num);
6158 	if (!inode) {
6159 		status = -EINVAL;
6160 		mlog(ML_ERROR, "Could not get load truncate log inode!\n");
6161 		goto bail;
6162 	}
6163 
6164 	status = ocfs2_read_inode_block(inode, &bh);
6165 	if (status < 0) {
6166 		iput(inode);
6167 		mlog_errno(status);
6168 		goto bail;
6169 	}
6170 
6171 	*tl_inode = inode;
6172 	*tl_bh    = bh;
6173 bail:
6174 	return status;
6175 }
6176 
6177 /* called during the 1st stage of node recovery. we stamp a clean
6178  * truncate log and pass back a copy for processing later. if the
6179  * truncate log does not require processing, a *tl_copy is set to
6180  * NULL. */
ocfs2_begin_truncate_log_recovery(struct ocfs2_super * osb,int slot_num,struct ocfs2_dinode ** tl_copy)6181 int ocfs2_begin_truncate_log_recovery(struct ocfs2_super *osb,
6182 				      int slot_num,
6183 				      struct ocfs2_dinode **tl_copy)
6184 {
6185 	int status;
6186 	struct inode *tl_inode = NULL;
6187 	struct buffer_head *tl_bh = NULL;
6188 	struct ocfs2_dinode *di;
6189 	struct ocfs2_truncate_log *tl;
6190 
6191 	*tl_copy = NULL;
6192 
6193 	trace_ocfs2_begin_truncate_log_recovery(slot_num);
6194 
6195 	status = ocfs2_get_truncate_log_info(osb, slot_num, &tl_inode, &tl_bh);
6196 	if (status < 0) {
6197 		mlog_errno(status);
6198 		goto bail;
6199 	}
6200 
6201 	di = (struct ocfs2_dinode *) tl_bh->b_data;
6202 
6203 	/* tl_bh is loaded from ocfs2_get_truncate_log_info().  It's
6204 	 * validated by the underlying call to ocfs2_read_inode_block(),
6205 	 * so any corruption is a code bug */
6206 	BUG_ON(!OCFS2_IS_VALID_DINODE(di));
6207 
6208 	tl = &di->id2.i_dealloc;
6209 	if (le16_to_cpu(tl->tl_used)) {
6210 		trace_ocfs2_truncate_log_recovery_num(le16_to_cpu(tl->tl_used));
6211 
6212 		*tl_copy = kmalloc(tl_bh->b_size, GFP_KERNEL);
6213 		if (!(*tl_copy)) {
6214 			status = -ENOMEM;
6215 			mlog_errno(status);
6216 			goto bail;
6217 		}
6218 
6219 		/* Assuming the write-out below goes well, this copy
6220 		 * will be passed back to recovery for processing. */
6221 		memcpy(*tl_copy, tl_bh->b_data, tl_bh->b_size);
6222 
6223 		/* All we need to do to clear the truncate log is set
6224 		 * tl_used. */
6225 		tl->tl_used = 0;
6226 
6227 		ocfs2_compute_meta_ecc(osb->sb, tl_bh->b_data, &di->i_check);
6228 		status = ocfs2_write_block(osb, tl_bh, INODE_CACHE(tl_inode));
6229 		if (status < 0) {
6230 			mlog_errno(status);
6231 			goto bail;
6232 		}
6233 	}
6234 
6235 bail:
6236 	iput(tl_inode);
6237 	brelse(tl_bh);
6238 
6239 	if (status < 0) {
6240 		kfree(*tl_copy);
6241 		*tl_copy = NULL;
6242 		mlog_errno(status);
6243 	}
6244 
6245 	return status;
6246 }
6247 
ocfs2_complete_truncate_log_recovery(struct ocfs2_super * osb,struct ocfs2_dinode * tl_copy)6248 int ocfs2_complete_truncate_log_recovery(struct ocfs2_super *osb,
6249 					 struct ocfs2_dinode *tl_copy)
6250 {
6251 	int status = 0;
6252 	int i;
6253 	unsigned int clusters, num_recs, start_cluster;
6254 	u64 start_blk;
6255 	handle_t *handle;
6256 	struct inode *tl_inode = osb->osb_tl_inode;
6257 	struct ocfs2_truncate_log *tl;
6258 
6259 	if (OCFS2_I(tl_inode)->ip_blkno == le64_to_cpu(tl_copy->i_blkno)) {
6260 		mlog(ML_ERROR, "Asked to recover my own truncate log!\n");
6261 		return -EINVAL;
6262 	}
6263 
6264 	tl = &tl_copy->id2.i_dealloc;
6265 	num_recs = le16_to_cpu(tl->tl_used);
6266 	trace_ocfs2_complete_truncate_log_recovery(
6267 		(unsigned long long)le64_to_cpu(tl_copy->i_blkno),
6268 		num_recs);
6269 
6270 	inode_lock(tl_inode);
6271 	for(i = 0; i < num_recs; i++) {
6272 		if (ocfs2_truncate_log_needs_flush(osb)) {
6273 			status = __ocfs2_flush_truncate_log(osb);
6274 			if (status < 0) {
6275 				mlog_errno(status);
6276 				goto bail_up;
6277 			}
6278 		}
6279 
6280 		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
6281 		if (IS_ERR(handle)) {
6282 			status = PTR_ERR(handle);
6283 			mlog_errno(status);
6284 			goto bail_up;
6285 		}
6286 
6287 		clusters = le32_to_cpu(tl->tl_recs[i].t_clusters);
6288 		start_cluster = le32_to_cpu(tl->tl_recs[i].t_start);
6289 		start_blk = ocfs2_clusters_to_blocks(osb->sb, start_cluster);
6290 
6291 		status = ocfs2_truncate_log_append(osb, handle,
6292 						   start_blk, clusters);
6293 		ocfs2_commit_trans(osb, handle);
6294 		if (status < 0) {
6295 			mlog_errno(status);
6296 			goto bail_up;
6297 		}
6298 	}
6299 
6300 bail_up:
6301 	inode_unlock(tl_inode);
6302 
6303 	return status;
6304 }
6305 
ocfs2_truncate_log_shutdown(struct ocfs2_super * osb)6306 void ocfs2_truncate_log_shutdown(struct ocfs2_super *osb)
6307 {
6308 	int status;
6309 	struct inode *tl_inode = osb->osb_tl_inode;
6310 
6311 	atomic_set(&osb->osb_tl_disable, 1);
6312 
6313 	if (tl_inode) {
6314 		cancel_delayed_work(&osb->osb_truncate_log_wq);
6315 		flush_workqueue(osb->ocfs2_wq);
6316 
6317 		status = ocfs2_flush_truncate_log(osb);
6318 		if (status < 0)
6319 			mlog_errno(status);
6320 
6321 		brelse(osb->osb_tl_bh);
6322 		iput(osb->osb_tl_inode);
6323 	}
6324 }
6325 
ocfs2_truncate_log_init(struct ocfs2_super * osb)6326 int ocfs2_truncate_log_init(struct ocfs2_super *osb)
6327 {
6328 	int status;
6329 	struct inode *tl_inode = NULL;
6330 	struct buffer_head *tl_bh = NULL;
6331 
6332 	status = ocfs2_get_truncate_log_info(osb,
6333 					     osb->slot_num,
6334 					     &tl_inode,
6335 					     &tl_bh);
6336 	if (status < 0)
6337 		mlog_errno(status);
6338 
6339 	/* ocfs2_truncate_log_shutdown keys on the existence of
6340 	 * osb->osb_tl_inode so we don't set any of the osb variables
6341 	 * until we're sure all is well. */
6342 	INIT_DELAYED_WORK(&osb->osb_truncate_log_wq,
6343 			  ocfs2_truncate_log_worker);
6344 	atomic_set(&osb->osb_tl_disable, 0);
6345 	osb->osb_tl_bh    = tl_bh;
6346 	osb->osb_tl_inode = tl_inode;
6347 
6348 	return status;
6349 }
6350 
6351 /*
6352  * Delayed de-allocation of suballocator blocks.
6353  *
6354  * Some sets of block de-allocations might involve multiple suballocator inodes.
6355  *
6356  * The locking for this can get extremely complicated, especially when
6357  * the suballocator inodes to delete from aren't known until deep
6358  * within an unrelated codepath.
6359  *
6360  * ocfs2_extent_block structures are a good example of this - an inode
6361  * btree could have been grown by any number of nodes each allocating
6362  * out of their own suballoc inode.
6363  *
6364  * These structures allow the delay of block de-allocation until a
6365  * later time, when locking of multiple cluster inodes won't cause
6366  * deadlock.
6367  */
6368 
6369 /*
6370  * Describe a single bit freed from a suballocator.  For the block
6371  * suballocators, it represents one block.  For the global cluster
6372  * allocator, it represents some clusters and free_bit indicates
6373  * clusters number.
6374  */
6375 struct ocfs2_cached_block_free {
6376 	struct ocfs2_cached_block_free		*free_next;
6377 	u64					free_bg;
6378 	u64					free_blk;
6379 	unsigned int				free_bit;
6380 };
6381 
6382 struct ocfs2_per_slot_free_list {
6383 	struct ocfs2_per_slot_free_list		*f_next_suballocator;
6384 	int					f_inode_type;
6385 	int					f_slot;
6386 	struct ocfs2_cached_block_free		*f_first;
6387 };
6388 
ocfs2_free_cached_blocks(struct ocfs2_super * osb,int sysfile_type,int slot,struct ocfs2_cached_block_free * head)6389 static int ocfs2_free_cached_blocks(struct ocfs2_super *osb,
6390 				    int sysfile_type,
6391 				    int slot,
6392 				    struct ocfs2_cached_block_free *head)
6393 {
6394 	int ret;
6395 	u64 bg_blkno;
6396 	handle_t *handle;
6397 	struct inode *inode;
6398 	struct buffer_head *di_bh = NULL;
6399 	struct ocfs2_cached_block_free *tmp;
6400 
6401 	inode = ocfs2_get_system_file_inode(osb, sysfile_type, slot);
6402 	if (!inode) {
6403 		ret = -EINVAL;
6404 		mlog_errno(ret);
6405 		goto out;
6406 	}
6407 
6408 	inode_lock(inode);
6409 
6410 	ret = ocfs2_inode_lock(inode, &di_bh, 1);
6411 	if (ret) {
6412 		mlog_errno(ret);
6413 		goto out_mutex;
6414 	}
6415 
6416 	while (head) {
6417 		if (head->free_bg)
6418 			bg_blkno = head->free_bg;
6419 		else
6420 			bg_blkno = ocfs2_which_suballoc_group(head->free_blk,
6421 							      head->free_bit);
6422 		handle = ocfs2_start_trans(osb, OCFS2_SUBALLOC_FREE);
6423 		if (IS_ERR(handle)) {
6424 			ret = PTR_ERR(handle);
6425 			mlog_errno(ret);
6426 			goto out_unlock;
6427 		}
6428 
6429 		trace_ocfs2_free_cached_blocks(
6430 		     (unsigned long long)head->free_blk, head->free_bit);
6431 
6432 		ret = ocfs2_free_suballoc_bits(handle, inode, di_bh,
6433 					       head->free_bit, bg_blkno, 1);
6434 		if (ret)
6435 			mlog_errno(ret);
6436 
6437 		ocfs2_commit_trans(osb, handle);
6438 
6439 		tmp = head;
6440 		head = head->free_next;
6441 		kfree(tmp);
6442 	}
6443 
6444 out_unlock:
6445 	ocfs2_inode_unlock(inode, 1);
6446 	brelse(di_bh);
6447 out_mutex:
6448 	inode_unlock(inode);
6449 	iput(inode);
6450 out:
6451 	while(head) {
6452 		/* Premature exit may have left some dangling items. */
6453 		tmp = head;
6454 		head = head->free_next;
6455 		kfree(tmp);
6456 	}
6457 
6458 	return ret;
6459 }
6460 
ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt * ctxt,u64 blkno,unsigned int bit)6461 int ocfs2_cache_cluster_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
6462 				u64 blkno, unsigned int bit)
6463 {
6464 	int ret = 0;
6465 	struct ocfs2_cached_block_free *item;
6466 
6467 	item = kzalloc(sizeof(*item), GFP_NOFS);
6468 	if (item == NULL) {
6469 		ret = -ENOMEM;
6470 		mlog_errno(ret);
6471 		return ret;
6472 	}
6473 
6474 	trace_ocfs2_cache_cluster_dealloc((unsigned long long)blkno, bit);
6475 
6476 	item->free_blk = blkno;
6477 	item->free_bit = bit;
6478 	item->free_next = ctxt->c_global_allocator;
6479 
6480 	ctxt->c_global_allocator = item;
6481 	return ret;
6482 }
6483 
ocfs2_free_cached_clusters(struct ocfs2_super * osb,struct ocfs2_cached_block_free * head)6484 static int ocfs2_free_cached_clusters(struct ocfs2_super *osb,
6485 				      struct ocfs2_cached_block_free *head)
6486 {
6487 	struct ocfs2_cached_block_free *tmp;
6488 	struct inode *tl_inode = osb->osb_tl_inode;
6489 	handle_t *handle;
6490 	int ret = 0;
6491 
6492 	inode_lock(tl_inode);
6493 
6494 	while (head) {
6495 		if (ocfs2_truncate_log_needs_flush(osb)) {
6496 			ret = __ocfs2_flush_truncate_log(osb);
6497 			if (ret < 0) {
6498 				mlog_errno(ret);
6499 				break;
6500 			}
6501 		}
6502 
6503 		handle = ocfs2_start_trans(osb, OCFS2_TRUNCATE_LOG_UPDATE);
6504 		if (IS_ERR(handle)) {
6505 			ret = PTR_ERR(handle);
6506 			mlog_errno(ret);
6507 			break;
6508 		}
6509 
6510 		ret = ocfs2_truncate_log_append(osb, handle, head->free_blk,
6511 						head->free_bit);
6512 
6513 		ocfs2_commit_trans(osb, handle);
6514 		tmp = head;
6515 		head = head->free_next;
6516 		kfree(tmp);
6517 
6518 		if (ret < 0) {
6519 			mlog_errno(ret);
6520 			break;
6521 		}
6522 	}
6523 
6524 	inode_unlock(tl_inode);
6525 
6526 	while (head) {
6527 		/* Premature exit may have left some dangling items. */
6528 		tmp = head;
6529 		head = head->free_next;
6530 		kfree(tmp);
6531 	}
6532 
6533 	return ret;
6534 }
6535 
ocfs2_run_deallocs(struct ocfs2_super * osb,struct ocfs2_cached_dealloc_ctxt * ctxt)6536 int ocfs2_run_deallocs(struct ocfs2_super *osb,
6537 		       struct ocfs2_cached_dealloc_ctxt *ctxt)
6538 {
6539 	int ret = 0, ret2;
6540 	struct ocfs2_per_slot_free_list *fl;
6541 
6542 	if (!ctxt)
6543 		return 0;
6544 
6545 	while (ctxt->c_first_suballocator) {
6546 		fl = ctxt->c_first_suballocator;
6547 
6548 		if (fl->f_first) {
6549 			trace_ocfs2_run_deallocs(fl->f_inode_type,
6550 						 fl->f_slot);
6551 			ret2 = ocfs2_free_cached_blocks(osb,
6552 							fl->f_inode_type,
6553 							fl->f_slot,
6554 							fl->f_first);
6555 			if (ret2)
6556 				mlog_errno(ret2);
6557 			if (!ret)
6558 				ret = ret2;
6559 		}
6560 
6561 		ctxt->c_first_suballocator = fl->f_next_suballocator;
6562 		kfree(fl);
6563 	}
6564 
6565 	if (ctxt->c_global_allocator) {
6566 		ret2 = ocfs2_free_cached_clusters(osb,
6567 						  ctxt->c_global_allocator);
6568 		if (ret2)
6569 			mlog_errno(ret2);
6570 		if (!ret)
6571 			ret = ret2;
6572 
6573 		ctxt->c_global_allocator = NULL;
6574 	}
6575 
6576 	return ret;
6577 }
6578 
6579 static struct ocfs2_per_slot_free_list *
ocfs2_find_per_slot_free_list(int type,int slot,struct ocfs2_cached_dealloc_ctxt * ctxt)6580 ocfs2_find_per_slot_free_list(int type,
6581 			      int slot,
6582 			      struct ocfs2_cached_dealloc_ctxt *ctxt)
6583 {
6584 	struct ocfs2_per_slot_free_list *fl = ctxt->c_first_suballocator;
6585 
6586 	while (fl) {
6587 		if (fl->f_inode_type == type && fl->f_slot == slot)
6588 			return fl;
6589 
6590 		fl = fl->f_next_suballocator;
6591 	}
6592 
6593 	fl = kmalloc(sizeof(*fl), GFP_NOFS);
6594 	if (fl) {
6595 		fl->f_inode_type = type;
6596 		fl->f_slot = slot;
6597 		fl->f_first = NULL;
6598 		fl->f_next_suballocator = ctxt->c_first_suballocator;
6599 
6600 		ctxt->c_first_suballocator = fl;
6601 	}
6602 	return fl;
6603 }
6604 
6605 static struct ocfs2_per_slot_free_list *
ocfs2_find_preferred_free_list(int type,int preferred_slot,int * real_slot,struct ocfs2_cached_dealloc_ctxt * ctxt)6606 ocfs2_find_preferred_free_list(int type,
6607 			       int preferred_slot,
6608 			       int *real_slot,
6609 			       struct ocfs2_cached_dealloc_ctxt *ctxt)
6610 {
6611 	struct ocfs2_per_slot_free_list *fl = ctxt->c_first_suballocator;
6612 
6613 	while (fl) {
6614 		if (fl->f_inode_type == type && fl->f_slot == preferred_slot) {
6615 			*real_slot = fl->f_slot;
6616 			return fl;
6617 		}
6618 
6619 		fl = fl->f_next_suballocator;
6620 	}
6621 
6622 	/* If we can't find any free list matching preferred slot, just use
6623 	 * the first one.
6624 	 */
6625 	fl = ctxt->c_first_suballocator;
6626 	*real_slot = fl->f_slot;
6627 
6628 	return fl;
6629 }
6630 
6631 /* Return Value 1 indicates empty */
ocfs2_is_dealloc_empty(struct ocfs2_extent_tree * et)6632 static int ocfs2_is_dealloc_empty(struct ocfs2_extent_tree *et)
6633 {
6634 	struct ocfs2_per_slot_free_list *fl = NULL;
6635 
6636 	if (!et->et_dealloc)
6637 		return 1;
6638 
6639 	fl = et->et_dealloc->c_first_suballocator;
6640 	if (!fl)
6641 		return 1;
6642 
6643 	if (!fl->f_first)
6644 		return 1;
6645 
6646 	return 0;
6647 }
6648 
6649 /* If extent was deleted from tree due to extent rotation and merging, and
6650  * no metadata is reserved ahead of time. Try to reuse some extents
6651  * just deleted. This is only used to reuse extent blocks.
6652  * It is supposed to find enough extent blocks in dealloc if our estimation
6653  * on metadata is accurate.
6654  */
ocfs2_reuse_blk_from_dealloc(handle_t * handle,struct ocfs2_extent_tree * et,struct buffer_head ** new_eb_bh,int blk_wanted,int * blk_given)6655 static int ocfs2_reuse_blk_from_dealloc(handle_t *handle,
6656 					struct ocfs2_extent_tree *et,
6657 					struct buffer_head **new_eb_bh,
6658 					int blk_wanted, int *blk_given)
6659 {
6660 	int i, status = 0, real_slot;
6661 	struct ocfs2_cached_dealloc_ctxt *dealloc;
6662 	struct ocfs2_per_slot_free_list *fl;
6663 	struct ocfs2_cached_block_free *bf;
6664 	struct ocfs2_extent_block *eb;
6665 	struct ocfs2_super *osb =
6666 		OCFS2_SB(ocfs2_metadata_cache_get_super(et->et_ci));
6667 
6668 	*blk_given = 0;
6669 
6670 	/* If extent tree doesn't have a dealloc, this is not faulty. Just
6671 	 * tell upper caller dealloc can't provide any block and it should
6672 	 * ask for alloc to claim more space.
6673 	 */
6674 	dealloc = et->et_dealloc;
6675 	if (!dealloc)
6676 		goto bail;
6677 
6678 	for (i = 0; i < blk_wanted; i++) {
6679 		/* Prefer to use local slot */
6680 		fl = ocfs2_find_preferred_free_list(EXTENT_ALLOC_SYSTEM_INODE,
6681 						    osb->slot_num, &real_slot,
6682 						    dealloc);
6683 		/* If no more block can be reused, we should claim more
6684 		 * from alloc. Just return here normally.
6685 		 */
6686 		if (!fl) {
6687 			status = 0;
6688 			break;
6689 		}
6690 
6691 		bf = fl->f_first;
6692 		fl->f_first = bf->free_next;
6693 
6694 		new_eb_bh[i] = sb_getblk(osb->sb, bf->free_blk);
6695 		if (new_eb_bh[i] == NULL) {
6696 			status = -ENOMEM;
6697 			mlog_errno(status);
6698 			goto bail;
6699 		}
6700 
6701 		mlog(0, "Reusing block(%llu) from "
6702 		     "dealloc(local slot:%d, real slot:%d)\n",
6703 		     bf->free_blk, osb->slot_num, real_slot);
6704 
6705 		ocfs2_set_new_buffer_uptodate(et->et_ci, new_eb_bh[i]);
6706 
6707 		status = ocfs2_journal_access_eb(handle, et->et_ci,
6708 						 new_eb_bh[i],
6709 						 OCFS2_JOURNAL_ACCESS_CREATE);
6710 		if (status < 0) {
6711 			mlog_errno(status);
6712 			goto bail;
6713 		}
6714 
6715 		memset(new_eb_bh[i]->b_data, 0, osb->sb->s_blocksize);
6716 		eb = (struct ocfs2_extent_block *) new_eb_bh[i]->b_data;
6717 
6718 		/* We can't guarantee that buffer head is still cached, so
6719 		 * polutlate the extent block again.
6720 		 */
6721 		strcpy(eb->h_signature, OCFS2_EXTENT_BLOCK_SIGNATURE);
6722 		eb->h_blkno = cpu_to_le64(bf->free_blk);
6723 		eb->h_fs_generation = cpu_to_le32(osb->fs_generation);
6724 		eb->h_suballoc_slot = cpu_to_le16(real_slot);
6725 		eb->h_suballoc_loc = cpu_to_le64(bf->free_bg);
6726 		eb->h_suballoc_bit = cpu_to_le16(bf->free_bit);
6727 		eb->h_list.l_count =
6728 			cpu_to_le16(ocfs2_extent_recs_per_eb(osb->sb));
6729 
6730 		/* We'll also be dirtied by the caller, so
6731 		 * this isn't absolutely necessary.
6732 		 */
6733 		ocfs2_journal_dirty(handle, new_eb_bh[i]);
6734 
6735 		if (!fl->f_first) {
6736 			dealloc->c_first_suballocator = fl->f_next_suballocator;
6737 			kfree(fl);
6738 		}
6739 		kfree(bf);
6740 	}
6741 
6742 	*blk_given = i;
6743 
6744 bail:
6745 	if (unlikely(status < 0)) {
6746 		for (i = 0; i < blk_wanted; i++)
6747 			brelse(new_eb_bh[i]);
6748 	}
6749 
6750 	return status;
6751 }
6752 
ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt * ctxt,int type,int slot,u64 suballoc,u64 blkno,unsigned int bit)6753 int ocfs2_cache_block_dealloc(struct ocfs2_cached_dealloc_ctxt *ctxt,
6754 			      int type, int slot, u64 suballoc,
6755 			      u64 blkno, unsigned int bit)
6756 {
6757 	int ret;
6758 	struct ocfs2_per_slot_free_list *fl;
6759 	struct ocfs2_cached_block_free *item;
6760 
6761 	fl = ocfs2_find_per_slot_free_list(type, slot, ctxt);
6762 	if (fl == NULL) {
6763 		ret = -ENOMEM;
6764 		mlog_errno(ret);
6765 		goto out;
6766 	}
6767 
6768 	item = kzalloc(sizeof(*item), GFP_NOFS);
6769 	if (item == NULL) {
6770 		ret = -ENOMEM;
6771 		mlog_errno(ret);
6772 		goto out;
6773 	}
6774 
6775 	trace_ocfs2_cache_block_dealloc(type, slot,
6776 					(unsigned long long)suballoc,
6777 					(unsigned long long)blkno, bit);
6778 
6779 	item->free_bg = suballoc;
6780 	item->free_blk = blkno;
6781 	item->free_bit = bit;
6782 	item->free_next = fl->f_first;
6783 
6784 	fl->f_first = item;
6785 
6786 	ret = 0;
6787 out:
6788 	return ret;
6789 }
6790 
ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt * ctxt,struct ocfs2_extent_block * eb)6791 static int ocfs2_cache_extent_block_free(struct ocfs2_cached_dealloc_ctxt *ctxt,
6792 					 struct ocfs2_extent_block *eb)
6793 {
6794 	return ocfs2_cache_block_dealloc(ctxt, EXTENT_ALLOC_SYSTEM_INODE,
6795 					 le16_to_cpu(eb->h_suballoc_slot),
6796 					 le64_to_cpu(eb->h_suballoc_loc),
6797 					 le64_to_cpu(eb->h_blkno),
6798 					 le16_to_cpu(eb->h_suballoc_bit));
6799 }
6800 
ocfs2_zero_func(handle_t * handle,struct buffer_head * bh)6801 static int ocfs2_zero_func(handle_t *handle, struct buffer_head *bh)
6802 {
6803 	set_buffer_uptodate(bh);
6804 	mark_buffer_dirty(bh);
6805 	return 0;
6806 }
6807 
ocfs2_map_and_dirty_page(struct inode * inode,handle_t * handle,unsigned int from,unsigned int to,struct page * page,int zero,u64 * phys)6808 void ocfs2_map_and_dirty_page(struct inode *inode, handle_t *handle,
6809 			      unsigned int from, unsigned int to,
6810 			      struct page *page, int zero, u64 *phys)
6811 {
6812 	int ret, partial = 0;
6813 
6814 	ret = ocfs2_map_page_blocks(page, phys, inode, from, to, 0);
6815 	if (ret)
6816 		mlog_errno(ret);
6817 
6818 	if (zero)
6819 		zero_user_segment(page, from, to);
6820 
6821 	/*
6822 	 * Need to set the buffers we zero'd into uptodate
6823 	 * here if they aren't - ocfs2_map_page_blocks()
6824 	 * might've skipped some
6825 	 */
6826 	ret = walk_page_buffers(handle, page_buffers(page),
6827 				from, to, &partial,
6828 				ocfs2_zero_func);
6829 	if (ret < 0)
6830 		mlog_errno(ret);
6831 	else if (ocfs2_should_order_data(inode)) {
6832 		ret = ocfs2_jbd2_file_inode(handle, inode);
6833 		if (ret < 0)
6834 			mlog_errno(ret);
6835 	}
6836 
6837 	if (!partial)
6838 		SetPageUptodate(page);
6839 
6840 	flush_dcache_page(page);
6841 }
6842 
ocfs2_zero_cluster_pages(struct inode * inode,loff_t start,loff_t end,struct page ** pages,int numpages,u64 phys,handle_t * handle)6843 static void ocfs2_zero_cluster_pages(struct inode *inode, loff_t start,
6844 				     loff_t end, struct page **pages,
6845 				     int numpages, u64 phys, handle_t *handle)
6846 {
6847 	int i;
6848 	struct page *page;
6849 	unsigned int from, to = PAGE_SIZE;
6850 	struct super_block *sb = inode->i_sb;
6851 
6852 	BUG_ON(!ocfs2_sparse_alloc(OCFS2_SB(sb)));
6853 
6854 	if (numpages == 0)
6855 		goto out;
6856 
6857 	to = PAGE_SIZE;
6858 	for(i = 0; i < numpages; i++) {
6859 		page = pages[i];
6860 
6861 		from = start & (PAGE_SIZE - 1);
6862 		if ((end >> PAGE_SHIFT) == page->index)
6863 			to = end & (PAGE_SIZE - 1);
6864 
6865 		BUG_ON(from > PAGE_SIZE);
6866 		BUG_ON(to > PAGE_SIZE);
6867 
6868 		ocfs2_map_and_dirty_page(inode, handle, from, to, page, 1,
6869 					 &phys);
6870 
6871 		start = (page->index + 1) << PAGE_SHIFT;
6872 	}
6873 out:
6874 	if (pages)
6875 		ocfs2_unlock_and_free_pages(pages, numpages);
6876 }
6877 
ocfs2_grab_pages(struct inode * inode,loff_t start,loff_t end,struct page ** pages,int * num)6878 int ocfs2_grab_pages(struct inode *inode, loff_t start, loff_t end,
6879 		     struct page **pages, int *num)
6880 {
6881 	int numpages, ret = 0;
6882 	struct address_space *mapping = inode->i_mapping;
6883 	unsigned long index;
6884 	loff_t last_page_bytes;
6885 
6886 	BUG_ON(start > end);
6887 
6888 	numpages = 0;
6889 	last_page_bytes = PAGE_ALIGN(end);
6890 	index = start >> PAGE_SHIFT;
6891 	do {
6892 		pages[numpages] = find_or_create_page(mapping, index, GFP_NOFS);
6893 		if (!pages[numpages]) {
6894 			ret = -ENOMEM;
6895 			mlog_errno(ret);
6896 			goto out;
6897 		}
6898 
6899 		numpages++;
6900 		index++;
6901 	} while (index < (last_page_bytes >> PAGE_SHIFT));
6902 
6903 out:
6904 	if (ret != 0) {
6905 		if (pages)
6906 			ocfs2_unlock_and_free_pages(pages, numpages);
6907 		numpages = 0;
6908 	}
6909 
6910 	*num = numpages;
6911 
6912 	return ret;
6913 }
6914 
ocfs2_grab_eof_pages(struct inode * inode,loff_t start,loff_t end,struct page ** pages,int * num)6915 static int ocfs2_grab_eof_pages(struct inode *inode, loff_t start, loff_t end,
6916 				struct page **pages, int *num)
6917 {
6918 	struct super_block *sb = inode->i_sb;
6919 
6920 	BUG_ON(start >> OCFS2_SB(sb)->s_clustersize_bits !=
6921 	       (end - 1) >> OCFS2_SB(sb)->s_clustersize_bits);
6922 
6923 	return ocfs2_grab_pages(inode, start, end, pages, num);
6924 }
6925 
6926 /*
6927  * Zero the area past i_size but still within an allocated
6928  * cluster. This avoids exposing nonzero data on subsequent file
6929  * extends.
6930  *
6931  * We need to call this before i_size is updated on the inode because
6932  * otherwise block_write_full_page() will skip writeout of pages past
6933  * i_size. The new_i_size parameter is passed for this reason.
6934  */
ocfs2_zero_range_for_truncate(struct inode * inode,handle_t * handle,u64 range_start,u64 range_end)6935 int ocfs2_zero_range_for_truncate(struct inode *inode, handle_t *handle,
6936 				  u64 range_start, u64 range_end)
6937 {
6938 	int ret = 0, numpages;
6939 	struct page **pages = NULL;
6940 	u64 phys;
6941 	unsigned int ext_flags;
6942 	struct super_block *sb = inode->i_sb;
6943 
6944 	/*
6945 	 * File systems which don't support sparse files zero on every
6946 	 * extend.
6947 	 */
6948 	if (!ocfs2_sparse_alloc(OCFS2_SB(sb)))
6949 		return 0;
6950 
6951 	pages = kcalloc(ocfs2_pages_per_cluster(sb),
6952 			sizeof(struct page *), GFP_NOFS);
6953 	if (pages == NULL) {
6954 		ret = -ENOMEM;
6955 		mlog_errno(ret);
6956 		goto out;
6957 	}
6958 
6959 	if (range_start == range_end)
6960 		goto out;
6961 
6962 	ret = ocfs2_extent_map_get_blocks(inode,
6963 					  range_start >> sb->s_blocksize_bits,
6964 					  &phys, NULL, &ext_flags);
6965 	if (ret) {
6966 		mlog_errno(ret);
6967 		goto out;
6968 	}
6969 
6970 	/*
6971 	 * Tail is a hole, or is marked unwritten. In either case, we
6972 	 * can count on read and write to return/push zero's.
6973 	 */
6974 	if (phys == 0 || ext_flags & OCFS2_EXT_UNWRITTEN)
6975 		goto out;
6976 
6977 	ret = ocfs2_grab_eof_pages(inode, range_start, range_end, pages,
6978 				   &numpages);
6979 	if (ret) {
6980 		mlog_errno(ret);
6981 		goto out;
6982 	}
6983 
6984 	ocfs2_zero_cluster_pages(inode, range_start, range_end, pages,
6985 				 numpages, phys, handle);
6986 
6987 	/*
6988 	 * Initiate writeout of the pages we zero'd here. We don't
6989 	 * wait on them - the truncate_inode_pages() call later will
6990 	 * do that for us.
6991 	 */
6992 	ret = filemap_fdatawrite_range(inode->i_mapping, range_start,
6993 				       range_end - 1);
6994 	if (ret)
6995 		mlog_errno(ret);
6996 
6997 out:
6998 	kfree(pages);
6999 
7000 	return ret;
7001 }
7002 
ocfs2_zero_dinode_id2_with_xattr(struct inode * inode,struct ocfs2_dinode * di)7003 static void ocfs2_zero_dinode_id2_with_xattr(struct inode *inode,
7004 					     struct ocfs2_dinode *di)
7005 {
7006 	unsigned int blocksize = 1 << inode->i_sb->s_blocksize_bits;
7007 	unsigned int xattrsize = le16_to_cpu(di->i_xattr_inline_size);
7008 
7009 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_XATTR_FL)
7010 		memset(&di->id2, 0, blocksize -
7011 				    offsetof(struct ocfs2_dinode, id2) -
7012 				    xattrsize);
7013 	else
7014 		memset(&di->id2, 0, blocksize -
7015 				    offsetof(struct ocfs2_dinode, id2));
7016 }
7017 
ocfs2_dinode_new_extent_list(struct inode * inode,struct ocfs2_dinode * di)7018 void ocfs2_dinode_new_extent_list(struct inode *inode,
7019 				  struct ocfs2_dinode *di)
7020 {
7021 	ocfs2_zero_dinode_id2_with_xattr(inode, di);
7022 	di->id2.i_list.l_tree_depth = 0;
7023 	di->id2.i_list.l_next_free_rec = 0;
7024 	di->id2.i_list.l_count = cpu_to_le16(
7025 		ocfs2_extent_recs_per_inode_with_xattr(inode->i_sb, di));
7026 }
7027 
ocfs2_set_inode_data_inline(struct inode * inode,struct ocfs2_dinode * di)7028 void ocfs2_set_inode_data_inline(struct inode *inode, struct ocfs2_dinode *di)
7029 {
7030 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
7031 	struct ocfs2_inline_data *idata = &di->id2.i_data;
7032 
7033 	spin_lock(&oi->ip_lock);
7034 	oi->ip_dyn_features |= OCFS2_INLINE_DATA_FL;
7035 	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
7036 	spin_unlock(&oi->ip_lock);
7037 
7038 	/*
7039 	 * We clear the entire i_data structure here so that all
7040 	 * fields can be properly initialized.
7041 	 */
7042 	ocfs2_zero_dinode_id2_with_xattr(inode, di);
7043 
7044 	idata->id_count = cpu_to_le16(
7045 			ocfs2_max_inline_data_with_xattr(inode->i_sb, di));
7046 }
7047 
ocfs2_convert_inline_data_to_extents(struct inode * inode,struct buffer_head * di_bh)7048 int ocfs2_convert_inline_data_to_extents(struct inode *inode,
7049 					 struct buffer_head *di_bh)
7050 {
7051 	int ret, has_data, num_pages = 0;
7052 	int need_free = 0;
7053 	u32 bit_off, num;
7054 	handle_t *handle;
7055 	u64 block;
7056 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
7057 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
7058 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7059 	struct ocfs2_alloc_context *data_ac = NULL;
7060 	struct page *page = NULL;
7061 	struct ocfs2_extent_tree et;
7062 	int did_quota = 0;
7063 
7064 	has_data = i_size_read(inode) ? 1 : 0;
7065 
7066 	if (has_data) {
7067 		ret = ocfs2_reserve_clusters(osb, 1, &data_ac);
7068 		if (ret) {
7069 			mlog_errno(ret);
7070 			goto out;
7071 		}
7072 	}
7073 
7074 	handle = ocfs2_start_trans(osb,
7075 				   ocfs2_inline_to_extents_credits(osb->sb));
7076 	if (IS_ERR(handle)) {
7077 		ret = PTR_ERR(handle);
7078 		mlog_errno(ret);
7079 		goto out;
7080 	}
7081 
7082 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
7083 				      OCFS2_JOURNAL_ACCESS_WRITE);
7084 	if (ret) {
7085 		mlog_errno(ret);
7086 		goto out_commit;
7087 	}
7088 
7089 	if (has_data) {
7090 		unsigned int page_end = min_t(unsigned, PAGE_SIZE,
7091 							osb->s_clustersize);
7092 		u64 phys;
7093 
7094 		ret = dquot_alloc_space_nodirty(inode,
7095 				       ocfs2_clusters_to_bytes(osb->sb, 1));
7096 		if (ret)
7097 			goto out_commit;
7098 		did_quota = 1;
7099 
7100 		data_ac->ac_resv = &oi->ip_la_data_resv;
7101 
7102 		ret = ocfs2_claim_clusters(handle, data_ac, 1, &bit_off,
7103 					   &num);
7104 		if (ret) {
7105 			mlog_errno(ret);
7106 			goto out_commit;
7107 		}
7108 
7109 		/*
7110 		 * Save two copies, one for insert, and one that can
7111 		 * be changed by ocfs2_map_and_dirty_page() below.
7112 		 */
7113 		block = phys = ocfs2_clusters_to_blocks(inode->i_sb, bit_off);
7114 
7115 		ret = ocfs2_grab_eof_pages(inode, 0, page_end, &page,
7116 					   &num_pages);
7117 		if (ret) {
7118 			mlog_errno(ret);
7119 			need_free = 1;
7120 			goto out_commit;
7121 		}
7122 
7123 		/*
7124 		 * This should populate the 1st page for us and mark
7125 		 * it up to date.
7126 		 */
7127 		ret = ocfs2_read_inline_data(inode, page, di_bh);
7128 		if (ret) {
7129 			mlog_errno(ret);
7130 			need_free = 1;
7131 			goto out_unlock;
7132 		}
7133 
7134 		ocfs2_map_and_dirty_page(inode, handle, 0, page_end, page, 0,
7135 					 &phys);
7136 	}
7137 
7138 	spin_lock(&oi->ip_lock);
7139 	oi->ip_dyn_features &= ~OCFS2_INLINE_DATA_FL;
7140 	di->i_dyn_features = cpu_to_le16(oi->ip_dyn_features);
7141 	spin_unlock(&oi->ip_lock);
7142 
7143 	ocfs2_update_inode_fsync_trans(handle, inode, 1);
7144 	ocfs2_dinode_new_extent_list(inode, di);
7145 
7146 	ocfs2_journal_dirty(handle, di_bh);
7147 
7148 	if (has_data) {
7149 		/*
7150 		 * An error at this point should be extremely rare. If
7151 		 * this proves to be false, we could always re-build
7152 		 * the in-inode data from our pages.
7153 		 */
7154 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
7155 		ret = ocfs2_insert_extent(handle, &et, 0, block, 1, 0, NULL);
7156 		if (ret) {
7157 			mlog_errno(ret);
7158 			need_free = 1;
7159 			goto out_unlock;
7160 		}
7161 
7162 		inode->i_blocks = ocfs2_inode_sector_count(inode);
7163 	}
7164 
7165 out_unlock:
7166 	if (page)
7167 		ocfs2_unlock_and_free_pages(&page, num_pages);
7168 
7169 out_commit:
7170 	if (ret < 0 && did_quota)
7171 		dquot_free_space_nodirty(inode,
7172 					  ocfs2_clusters_to_bytes(osb->sb, 1));
7173 
7174 	if (need_free) {
7175 		if (data_ac->ac_which == OCFS2_AC_USE_LOCAL)
7176 			ocfs2_free_local_alloc_bits(osb, handle, data_ac,
7177 					bit_off, num);
7178 		else
7179 			ocfs2_free_clusters(handle,
7180 					data_ac->ac_inode,
7181 					data_ac->ac_bh,
7182 					ocfs2_clusters_to_blocks(osb->sb, bit_off),
7183 					num);
7184 	}
7185 
7186 	ocfs2_commit_trans(osb, handle);
7187 
7188 out:
7189 	if (data_ac)
7190 		ocfs2_free_alloc_context(data_ac);
7191 	return ret;
7192 }
7193 
7194 /*
7195  * It is expected, that by the time you call this function,
7196  * inode->i_size and fe->i_size have been adjusted.
7197  *
7198  * WARNING: This will kfree the truncate context
7199  */
ocfs2_commit_truncate(struct ocfs2_super * osb,struct inode * inode,struct buffer_head * di_bh)7200 int ocfs2_commit_truncate(struct ocfs2_super *osb,
7201 			  struct inode *inode,
7202 			  struct buffer_head *di_bh)
7203 {
7204 	int status = 0, i, flags = 0;
7205 	u32 new_highest_cpos, range, trunc_cpos, trunc_len, phys_cpos, coff;
7206 	u64 blkno = 0;
7207 	struct ocfs2_extent_list *el;
7208 	struct ocfs2_extent_rec *rec;
7209 	struct ocfs2_path *path = NULL;
7210 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7211 	struct ocfs2_extent_list *root_el = &(di->id2.i_list);
7212 	u64 refcount_loc = le64_to_cpu(di->i_refcount_loc);
7213 	struct ocfs2_extent_tree et;
7214 	struct ocfs2_cached_dealloc_ctxt dealloc;
7215 	struct ocfs2_refcount_tree *ref_tree = NULL;
7216 
7217 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
7218 	ocfs2_init_dealloc_ctxt(&dealloc);
7219 
7220 	new_highest_cpos = ocfs2_clusters_for_bytes(osb->sb,
7221 						     i_size_read(inode));
7222 
7223 	path = ocfs2_new_path(di_bh, &di->id2.i_list,
7224 			      ocfs2_journal_access_di);
7225 	if (!path) {
7226 		status = -ENOMEM;
7227 		mlog_errno(status);
7228 		goto bail;
7229 	}
7230 
7231 	ocfs2_extent_map_trunc(inode, new_highest_cpos);
7232 
7233 start:
7234 	/*
7235 	 * Check that we still have allocation to delete.
7236 	 */
7237 	if (OCFS2_I(inode)->ip_clusters == 0) {
7238 		status = 0;
7239 		goto bail;
7240 	}
7241 
7242 	/*
7243 	 * Truncate always works against the rightmost tree branch.
7244 	 */
7245 	status = ocfs2_find_path(INODE_CACHE(inode), path, UINT_MAX);
7246 	if (status) {
7247 		mlog_errno(status);
7248 		goto bail;
7249 	}
7250 
7251 	trace_ocfs2_commit_truncate(
7252 		(unsigned long long)OCFS2_I(inode)->ip_blkno,
7253 		new_highest_cpos,
7254 		OCFS2_I(inode)->ip_clusters,
7255 		path->p_tree_depth);
7256 
7257 	/*
7258 	 * By now, el will point to the extent list on the bottom most
7259 	 * portion of this tree. Only the tail record is considered in
7260 	 * each pass.
7261 	 *
7262 	 * We handle the following cases, in order:
7263 	 * - empty extent: delete the remaining branch
7264 	 * - remove the entire record
7265 	 * - remove a partial record
7266 	 * - no record needs to be removed (truncate has completed)
7267 	 */
7268 	el = path_leaf_el(path);
7269 	if (le16_to_cpu(el->l_next_free_rec) == 0) {
7270 		ocfs2_error(inode->i_sb,
7271 			    "Inode %llu has empty extent block at %llu\n",
7272 			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
7273 			    (unsigned long long)path_leaf_bh(path)->b_blocknr);
7274 		status = -EROFS;
7275 		goto bail;
7276 	}
7277 
7278 	i = le16_to_cpu(el->l_next_free_rec) - 1;
7279 	rec = &el->l_recs[i];
7280 	flags = rec->e_flags;
7281 	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
7282 
7283 	if (i == 0 && ocfs2_is_empty_extent(rec)) {
7284 		/*
7285 		 * Lower levels depend on this never happening, but it's best
7286 		 * to check it up here before changing the tree.
7287 		*/
7288 		if (root_el->l_tree_depth && rec->e_int_clusters == 0) {
7289 			mlog(ML_ERROR, "Inode %lu has an empty "
7290 				    "extent record, depth %u\n", inode->i_ino,
7291 				    le16_to_cpu(root_el->l_tree_depth));
7292 			status = ocfs2_remove_rightmost_empty_extent(osb,
7293 					&et, path, &dealloc);
7294 			if (status) {
7295 				mlog_errno(status);
7296 				goto bail;
7297 			}
7298 
7299 			ocfs2_reinit_path(path, 1);
7300 			goto start;
7301 		} else {
7302 			trunc_cpos = le32_to_cpu(rec->e_cpos);
7303 			trunc_len = 0;
7304 			blkno = 0;
7305 		}
7306 	} else if (le32_to_cpu(rec->e_cpos) >= new_highest_cpos) {
7307 		/*
7308 		 * Truncate entire record.
7309 		 */
7310 		trunc_cpos = le32_to_cpu(rec->e_cpos);
7311 		trunc_len = ocfs2_rec_clusters(el, rec);
7312 		blkno = le64_to_cpu(rec->e_blkno);
7313 	} else if (range > new_highest_cpos) {
7314 		/*
7315 		 * Partial truncate. it also should be
7316 		 * the last truncate we're doing.
7317 		 */
7318 		trunc_cpos = new_highest_cpos;
7319 		trunc_len = range - new_highest_cpos;
7320 		coff = new_highest_cpos - le32_to_cpu(rec->e_cpos);
7321 		blkno = le64_to_cpu(rec->e_blkno) +
7322 				ocfs2_clusters_to_blocks(inode->i_sb, coff);
7323 	} else {
7324 		/*
7325 		 * Truncate completed, leave happily.
7326 		 */
7327 		status = 0;
7328 		goto bail;
7329 	}
7330 
7331 	phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
7332 
7333 	if ((flags & OCFS2_EXT_REFCOUNTED) && trunc_len && !ref_tree) {
7334 		status = ocfs2_lock_refcount_tree(osb, refcount_loc, 1,
7335 				&ref_tree, NULL);
7336 		if (status) {
7337 			mlog_errno(status);
7338 			goto bail;
7339 		}
7340 	}
7341 
7342 	status = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
7343 					  phys_cpos, trunc_len, flags, &dealloc,
7344 					  refcount_loc, true);
7345 	if (status < 0) {
7346 		mlog_errno(status);
7347 		goto bail;
7348 	}
7349 
7350 	ocfs2_reinit_path(path, 1);
7351 
7352 	/*
7353 	 * The check above will catch the case where we've truncated
7354 	 * away all allocation.
7355 	 */
7356 	goto start;
7357 
7358 bail:
7359 	if (ref_tree)
7360 		ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
7361 
7362 	ocfs2_schedule_truncate_log_flush(osb, 1);
7363 
7364 	ocfs2_run_deallocs(osb, &dealloc);
7365 
7366 	ocfs2_free_path(path);
7367 
7368 	return status;
7369 }
7370 
7371 /*
7372  * 'start' is inclusive, 'end' is not.
7373  */
ocfs2_truncate_inline(struct inode * inode,struct buffer_head * di_bh,unsigned int start,unsigned int end,int trunc)7374 int ocfs2_truncate_inline(struct inode *inode, struct buffer_head *di_bh,
7375 			  unsigned int start, unsigned int end, int trunc)
7376 {
7377 	int ret;
7378 	unsigned int numbytes;
7379 	handle_t *handle;
7380 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
7381 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
7382 	struct ocfs2_inline_data *idata = &di->id2.i_data;
7383 
7384 	/* No need to punch hole beyond i_size. */
7385 	if (start >= i_size_read(inode))
7386 		return 0;
7387 
7388 	if (end > i_size_read(inode))
7389 		end = i_size_read(inode);
7390 
7391 	BUG_ON(start > end);
7392 
7393 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) ||
7394 	    !(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL) ||
7395 	    !ocfs2_supports_inline_data(osb)) {
7396 		ocfs2_error(inode->i_sb,
7397 			    "Inline data flags for inode %llu don't agree! Disk: 0x%x, Memory: 0x%x, Superblock: 0x%x\n",
7398 			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
7399 			    le16_to_cpu(di->i_dyn_features),
7400 			    OCFS2_I(inode)->ip_dyn_features,
7401 			    osb->s_feature_incompat);
7402 		ret = -EROFS;
7403 		goto out;
7404 	}
7405 
7406 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
7407 	if (IS_ERR(handle)) {
7408 		ret = PTR_ERR(handle);
7409 		mlog_errno(ret);
7410 		goto out;
7411 	}
7412 
7413 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
7414 				      OCFS2_JOURNAL_ACCESS_WRITE);
7415 	if (ret) {
7416 		mlog_errno(ret);
7417 		goto out_commit;
7418 	}
7419 
7420 	numbytes = end - start;
7421 	memset(idata->id_data + start, 0, numbytes);
7422 
7423 	/*
7424 	 * No need to worry about the data page here - it's been
7425 	 * truncated already and inline data doesn't need it for
7426 	 * pushing zero's to disk, so we'll let readpage pick it up
7427 	 * later.
7428 	 */
7429 	if (trunc) {
7430 		i_size_write(inode, start);
7431 		di->i_size = cpu_to_le64(start);
7432 	}
7433 
7434 	inode->i_blocks = ocfs2_inode_sector_count(inode);
7435 	inode->i_ctime = inode->i_mtime = current_time(inode);
7436 
7437 	di->i_ctime = di->i_mtime = cpu_to_le64(inode->i_ctime.tv_sec);
7438 	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
7439 
7440 	ocfs2_update_inode_fsync_trans(handle, inode, 1);
7441 	ocfs2_journal_dirty(handle, di_bh);
7442 
7443 out_commit:
7444 	ocfs2_commit_trans(osb, handle);
7445 
7446 out:
7447 	return ret;
7448 }
7449 
ocfs2_trim_extent(struct super_block * sb,struct ocfs2_group_desc * gd,u64 group,u32 start,u32 count)7450 static int ocfs2_trim_extent(struct super_block *sb,
7451 			     struct ocfs2_group_desc *gd,
7452 			     u64 group, u32 start, u32 count)
7453 {
7454 	u64 discard, bcount;
7455 	struct ocfs2_super *osb = OCFS2_SB(sb);
7456 
7457 	bcount = ocfs2_clusters_to_blocks(sb, count);
7458 	discard = ocfs2_clusters_to_blocks(sb, start);
7459 
7460 	/*
7461 	 * For the first cluster group, the gd->bg_blkno is not at the start
7462 	 * of the group, but at an offset from the start. If we add it while
7463 	 * calculating discard for first group, we will wrongly start fstrim a
7464 	 * few blocks after the desried start block and the range can cross
7465 	 * over into the next cluster group. So, add it only if this is not
7466 	 * the first cluster group.
7467 	 */
7468 	if (group != osb->first_cluster_group_blkno)
7469 		discard += le64_to_cpu(gd->bg_blkno);
7470 
7471 	trace_ocfs2_trim_extent(sb, (unsigned long long)discard, bcount);
7472 
7473 	return sb_issue_discard(sb, discard, bcount, GFP_NOFS, 0);
7474 }
7475 
ocfs2_trim_group(struct super_block * sb,struct ocfs2_group_desc * gd,u64 group,u32 start,u32 max,u32 minbits)7476 static int ocfs2_trim_group(struct super_block *sb,
7477 			    struct ocfs2_group_desc *gd, u64 group,
7478 			    u32 start, u32 max, u32 minbits)
7479 {
7480 	int ret = 0, count = 0, next;
7481 	void *bitmap = gd->bg_bitmap;
7482 
7483 	if (le16_to_cpu(gd->bg_free_bits_count) < minbits)
7484 		return 0;
7485 
7486 	trace_ocfs2_trim_group((unsigned long long)le64_to_cpu(gd->bg_blkno),
7487 			       start, max, minbits);
7488 
7489 	while (start < max) {
7490 		start = ocfs2_find_next_zero_bit(bitmap, max, start);
7491 		if (start >= max)
7492 			break;
7493 		next = ocfs2_find_next_bit(bitmap, max, start);
7494 
7495 		if ((next - start) >= minbits) {
7496 			ret = ocfs2_trim_extent(sb, gd, group,
7497 						start, next - start);
7498 			if (ret < 0) {
7499 				mlog_errno(ret);
7500 				break;
7501 			}
7502 			count += next - start;
7503 		}
7504 		start = next + 1;
7505 
7506 		if (fatal_signal_pending(current)) {
7507 			count = -ERESTARTSYS;
7508 			break;
7509 		}
7510 
7511 		if ((le16_to_cpu(gd->bg_free_bits_count) - count) < minbits)
7512 			break;
7513 	}
7514 
7515 	if (ret < 0)
7516 		count = ret;
7517 
7518 	return count;
7519 }
7520 
ocfs2_trim_fs(struct super_block * sb,struct fstrim_range * range)7521 int ocfs2_trim_fs(struct super_block *sb, struct fstrim_range *range)
7522 {
7523 	struct ocfs2_super *osb = OCFS2_SB(sb);
7524 	u64 start, len, trimmed, first_group, last_group, group;
7525 	int ret, cnt;
7526 	u32 first_bit, last_bit, minlen;
7527 	struct buffer_head *main_bm_bh = NULL;
7528 	struct inode *main_bm_inode = NULL;
7529 	struct buffer_head *gd_bh = NULL;
7530 	struct ocfs2_dinode *main_bm;
7531 	struct ocfs2_group_desc *gd = NULL;
7532 	struct ocfs2_trim_fs_info info, *pinfo = NULL;
7533 
7534 	start = range->start >> osb->s_clustersize_bits;
7535 	len = range->len >> osb->s_clustersize_bits;
7536 	minlen = range->minlen >> osb->s_clustersize_bits;
7537 
7538 	if (minlen >= osb->bitmap_cpg || range->len < sb->s_blocksize)
7539 		return -EINVAL;
7540 
7541 	main_bm_inode = ocfs2_get_system_file_inode(osb,
7542 						    GLOBAL_BITMAP_SYSTEM_INODE,
7543 						    OCFS2_INVALID_SLOT);
7544 	if (!main_bm_inode) {
7545 		ret = -EIO;
7546 		mlog_errno(ret);
7547 		goto out;
7548 	}
7549 
7550 	inode_lock(main_bm_inode);
7551 
7552 	ret = ocfs2_inode_lock(main_bm_inode, &main_bm_bh, 0);
7553 	if (ret < 0) {
7554 		mlog_errno(ret);
7555 		goto out_mutex;
7556 	}
7557 	main_bm = (struct ocfs2_dinode *)main_bm_bh->b_data;
7558 
7559 	if (start >= le32_to_cpu(main_bm->i_clusters)) {
7560 		ret = -EINVAL;
7561 		goto out_unlock;
7562 	}
7563 
7564 	len = range->len >> osb->s_clustersize_bits;
7565 	if (start + len > le32_to_cpu(main_bm->i_clusters))
7566 		len = le32_to_cpu(main_bm->i_clusters) - start;
7567 
7568 	trace_ocfs2_trim_fs(start, len, minlen);
7569 
7570 	ocfs2_trim_fs_lock_res_init(osb);
7571 	ret = ocfs2_trim_fs_lock(osb, NULL, 1);
7572 	if (ret < 0) {
7573 		if (ret != -EAGAIN) {
7574 			mlog_errno(ret);
7575 			ocfs2_trim_fs_lock_res_uninit(osb);
7576 			goto out_unlock;
7577 		}
7578 
7579 		mlog(ML_NOTICE, "Wait for trim on device (%s) to "
7580 		     "finish, which is running from another node.\n",
7581 		     osb->dev_str);
7582 		ret = ocfs2_trim_fs_lock(osb, &info, 0);
7583 		if (ret < 0) {
7584 			mlog_errno(ret);
7585 			ocfs2_trim_fs_lock_res_uninit(osb);
7586 			goto out_unlock;
7587 		}
7588 
7589 		if (info.tf_valid && info.tf_success &&
7590 		    info.tf_start == start && info.tf_len == len &&
7591 		    info.tf_minlen == minlen) {
7592 			/* Avoid sending duplicated trim to a shared device */
7593 			mlog(ML_NOTICE, "The same trim on device (%s) was "
7594 			     "just done from node (%u), return.\n",
7595 			     osb->dev_str, info.tf_nodenum);
7596 			range->len = info.tf_trimlen;
7597 			goto out_trimunlock;
7598 		}
7599 	}
7600 
7601 	info.tf_nodenum = osb->node_num;
7602 	info.tf_start = start;
7603 	info.tf_len = len;
7604 	info.tf_minlen = minlen;
7605 
7606 	/* Determine first and last group to examine based on start and len */
7607 	first_group = ocfs2_which_cluster_group(main_bm_inode, start);
7608 	if (first_group == osb->first_cluster_group_blkno)
7609 		first_bit = start;
7610 	else
7611 		first_bit = start - ocfs2_blocks_to_clusters(sb, first_group);
7612 	last_group = ocfs2_which_cluster_group(main_bm_inode, start + len - 1);
7613 	last_bit = osb->bitmap_cpg;
7614 
7615 	trimmed = 0;
7616 	for (group = first_group; group <= last_group;) {
7617 		if (first_bit + len >= osb->bitmap_cpg)
7618 			last_bit = osb->bitmap_cpg;
7619 		else
7620 			last_bit = first_bit + len;
7621 
7622 		ret = ocfs2_read_group_descriptor(main_bm_inode,
7623 						  main_bm, group,
7624 						  &gd_bh);
7625 		if (ret < 0) {
7626 			mlog_errno(ret);
7627 			break;
7628 		}
7629 
7630 		gd = (struct ocfs2_group_desc *)gd_bh->b_data;
7631 		cnt = ocfs2_trim_group(sb, gd, group,
7632 				       first_bit, last_bit, minlen);
7633 		brelse(gd_bh);
7634 		gd_bh = NULL;
7635 		if (cnt < 0) {
7636 			ret = cnt;
7637 			mlog_errno(ret);
7638 			break;
7639 		}
7640 
7641 		trimmed += cnt;
7642 		len -= osb->bitmap_cpg - first_bit;
7643 		first_bit = 0;
7644 		if (group == osb->first_cluster_group_blkno)
7645 			group = ocfs2_clusters_to_blocks(sb, osb->bitmap_cpg);
7646 		else
7647 			group += ocfs2_clusters_to_blocks(sb, osb->bitmap_cpg);
7648 	}
7649 	range->len = trimmed * sb->s_blocksize;
7650 
7651 	info.tf_trimlen = range->len;
7652 	info.tf_success = (ret ? 0 : 1);
7653 	pinfo = &info;
7654 out_trimunlock:
7655 	ocfs2_trim_fs_unlock(osb, pinfo);
7656 	ocfs2_trim_fs_lock_res_uninit(osb);
7657 out_unlock:
7658 	ocfs2_inode_unlock(main_bm_inode, 0);
7659 	brelse(main_bm_bh);
7660 out_mutex:
7661 	inode_unlock(main_bm_inode);
7662 	iput(main_bm_inode);
7663 out:
7664 	return ret;
7665 }
7666