1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * Copyright (C) 2014 Facebook. All rights reserved.
4 */
5
6 #ifndef BTRFS_QGROUP_H
7 #define BTRFS_QGROUP_H
8
9 #include "ulist.h"
10 #include "delayed-ref.h"
11
12 /*
13 * Btrfs qgroup overview
14 *
15 * Btrfs qgroup splits into 3 main part:
16 * 1) Reserve
17 * Reserve metadata/data space for incoming operations
18 * Affect how qgroup limit works
19 *
20 * 2) Trace
21 * Tell btrfs qgroup to trace dirty extents.
22 *
23 * Dirty extents including:
24 * - Newly allocated extents
25 * - Extents going to be deleted (in this trans)
26 * - Extents whose owner is going to be modified
27 *
28 * This is the main part affects whether qgroup numbers will stay
29 * consistent.
30 * Btrfs qgroup can trace clean extents and won't cause any problem,
31 * but it will consume extra CPU time, it should be avoided if possible.
32 *
33 * 3) Account
34 * Btrfs qgroup will updates its numbers, based on dirty extents traced
35 * in previous step.
36 *
37 * Normally at qgroup rescan and transaction commit time.
38 */
39
40 /*
41 * Record a dirty extent, and info qgroup to update quota on it
42 * TODO: Use kmem cache to alloc it.
43 */
44 struct btrfs_qgroup_extent_record {
45 struct rb_node node;
46 u64 bytenr;
47 u64 num_bytes;
48 struct ulist *old_roots;
49 };
50
51 /*
52 * Qgroup reservation types:
53 *
54 * DATA:
55 * space reserved for data
56 *
57 * META_PERTRANS:
58 * Space reserved for metadata (per-transaction)
59 * Due to the fact that qgroup data is only updated at transaction commit
60 * time, reserved space for metadata must be kept until transaction
61 * commits.
62 * Any metadata reserved that are used in btrfs_start_transaction() should
63 * be of this type.
64 *
65 * META_PREALLOC:
66 * There are cases where metadata space is reserved before starting
67 * transaction, and then btrfs_join_transaction() to get a trans handle.
68 * Any metadata reserved for such usage should be of this type.
69 * And after join_transaction() part (or all) of such reservation should
70 * be converted into META_PERTRANS.
71 */
72 enum btrfs_qgroup_rsv_type {
73 BTRFS_QGROUP_RSV_DATA = 0,
74 BTRFS_QGROUP_RSV_META_PERTRANS,
75 BTRFS_QGROUP_RSV_META_PREALLOC,
76 BTRFS_QGROUP_RSV_LAST,
77 };
78
79 /*
80 * Represents how many bytes we have reserved for this qgroup.
81 *
82 * Each type should have different reservation behavior.
83 * E.g, data follows its io_tree flag modification, while
84 * *currently* meta is just reserve-and-clear during transcation.
85 *
86 * TODO: Add new type for reservation which can survive transaction commit.
87 * Currect metadata reservation behavior is not suitable for such case.
88 */
89 struct btrfs_qgroup_rsv {
90 u64 values[BTRFS_QGROUP_RSV_LAST];
91 };
92
93 /*
94 * one struct for each qgroup, organized in fs_info->qgroup_tree.
95 */
96 struct btrfs_qgroup {
97 u64 qgroupid;
98
99 /*
100 * state
101 */
102 u64 rfer; /* referenced */
103 u64 rfer_cmpr; /* referenced compressed */
104 u64 excl; /* exclusive */
105 u64 excl_cmpr; /* exclusive compressed */
106
107 /*
108 * limits
109 */
110 u64 lim_flags; /* which limits are set */
111 u64 max_rfer;
112 u64 max_excl;
113 u64 rsv_rfer;
114 u64 rsv_excl;
115
116 /*
117 * reservation tracking
118 */
119 struct btrfs_qgroup_rsv rsv;
120
121 /*
122 * lists
123 */
124 struct list_head groups; /* groups this group is member of */
125 struct list_head members; /* groups that are members of this group */
126 struct list_head dirty; /* dirty groups */
127 struct rb_node node; /* tree of qgroups */
128
129 /*
130 * temp variables for accounting operations
131 * Refer to qgroup_shared_accounting() for details.
132 */
133 u64 old_refcnt;
134 u64 new_refcnt;
135 };
136
137 /*
138 * For qgroup event trace points only
139 */
140 #define QGROUP_RESERVE (1<<0)
141 #define QGROUP_RELEASE (1<<1)
142 #define QGROUP_FREE (1<<2)
143
144 int btrfs_quota_enable(struct btrfs_fs_info *fs_info);
145 int btrfs_quota_disable(struct btrfs_fs_info *fs_info);
146 int btrfs_qgroup_rescan(struct btrfs_fs_info *fs_info);
147 void btrfs_qgroup_rescan_resume(struct btrfs_fs_info *fs_info);
148 int btrfs_qgroup_wait_for_completion(struct btrfs_fs_info *fs_info,
149 bool interruptible);
150 int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
151 u64 dst);
152 int btrfs_del_qgroup_relation(struct btrfs_trans_handle *trans, u64 src,
153 u64 dst);
154 int btrfs_create_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid);
155 int btrfs_remove_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid);
156 int btrfs_limit_qgroup(struct btrfs_trans_handle *trans, u64 qgroupid,
157 struct btrfs_qgroup_limit *limit);
158 int btrfs_read_qgroup_config(struct btrfs_fs_info *fs_info);
159 void btrfs_free_qgroup_config(struct btrfs_fs_info *fs_info);
160 struct btrfs_delayed_extent_op;
161
162 /*
163 * Inform qgroup to trace one dirty extent, its info is recorded in @record.
164 * So qgroup can account it at transaction committing time.
165 *
166 * No lock version, caller must acquire delayed ref lock and allocated memory,
167 * then call btrfs_qgroup_trace_extent_post() after exiting lock context.
168 *
169 * Return 0 for success insert
170 * Return >0 for existing record, caller can free @record safely.
171 * Error is not possible
172 */
173 int btrfs_qgroup_trace_extent_nolock(
174 struct btrfs_fs_info *fs_info,
175 struct btrfs_delayed_ref_root *delayed_refs,
176 struct btrfs_qgroup_extent_record *record);
177
178 /*
179 * Post handler after qgroup_trace_extent_nolock().
180 *
181 * NOTE: Current qgroup does the expensive backref walk at transaction
182 * committing time with TRANS_STATE_COMMIT_DOING, this blocks incoming
183 * new transaction.
184 * This is designed to allow btrfs_find_all_roots() to get correct new_roots
185 * result.
186 *
187 * However for old_roots there is no need to do backref walk at that time,
188 * since we search commit roots to walk backref and result will always be
189 * correct.
190 *
191 * Due to the nature of no lock version, we can't do backref there.
192 * So we must call btrfs_qgroup_trace_extent_post() after exiting
193 * spinlock context.
194 *
195 * TODO: If we can fix and prove btrfs_find_all_roots() can get correct result
196 * using current root, then we can move all expensive backref walk out of
197 * transaction committing, but not now as qgroup accounting will be wrong again.
198 */
199 int btrfs_qgroup_trace_extent_post(struct btrfs_fs_info *fs_info,
200 struct btrfs_qgroup_extent_record *qrecord);
201
202 /*
203 * Inform qgroup to trace one dirty extent, specified by @bytenr and
204 * @num_bytes.
205 * So qgroup can account it at commit trans time.
206 *
207 * Better encapsulated version, with memory allocation and backref walk for
208 * commit roots.
209 * So this can sleep.
210 *
211 * Return 0 if the operation is done.
212 * Return <0 for error, like memory allocation failure or invalid parameter
213 * (NULL trans)
214 */
215 int btrfs_qgroup_trace_extent(struct btrfs_trans_handle *trans, u64 bytenr,
216 u64 num_bytes, gfp_t gfp_flag);
217
218 /*
219 * Inform qgroup to trace all leaf items of data
220 *
221 * Return 0 for success
222 * Return <0 for error(ENOMEM)
223 */
224 int btrfs_qgroup_trace_leaf_items(struct btrfs_trans_handle *trans,
225 struct extent_buffer *eb);
226 /*
227 * Inform qgroup to trace a whole subtree, including all its child tree
228 * blocks and data.
229 * The root tree block is specified by @root_eb.
230 *
231 * Normally used by relocation(tree block swap) and subvolume deletion.
232 *
233 * Return 0 for success
234 * Return <0 for error(ENOMEM or tree search error)
235 */
236 int btrfs_qgroup_trace_subtree(struct btrfs_trans_handle *trans,
237 struct extent_buffer *root_eb,
238 u64 root_gen, int root_level);
239 int btrfs_qgroup_account_extent(struct btrfs_trans_handle *trans, u64 bytenr,
240 u64 num_bytes, struct ulist *old_roots,
241 struct ulist *new_roots);
242 int btrfs_qgroup_account_extents(struct btrfs_trans_handle *trans);
243 int btrfs_run_qgroups(struct btrfs_trans_handle *trans);
244 int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, u64 srcid,
245 u64 objectid, struct btrfs_qgroup_inherit *inherit);
246 void btrfs_qgroup_free_refroot(struct btrfs_fs_info *fs_info,
247 u64 ref_root, u64 num_bytes,
248 enum btrfs_qgroup_rsv_type type);
btrfs_qgroup_free_delayed_ref(struct btrfs_fs_info * fs_info,u64 ref_root,u64 num_bytes)249 static inline void btrfs_qgroup_free_delayed_ref(struct btrfs_fs_info *fs_info,
250 u64 ref_root, u64 num_bytes)
251 {
252 if (!test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags))
253 return;
254 trace_btrfs_qgroup_free_delayed_ref(fs_info, ref_root, num_bytes);
255 btrfs_qgroup_free_refroot(fs_info, ref_root, num_bytes,
256 BTRFS_QGROUP_RSV_DATA);
257 }
258
259 #ifdef CONFIG_BTRFS_FS_RUN_SANITY_TESTS
260 int btrfs_verify_qgroup_counts(struct btrfs_fs_info *fs_info, u64 qgroupid,
261 u64 rfer, u64 excl);
262 #endif
263
264 /* New io_tree based accurate qgroup reserve API */
265 int btrfs_qgroup_reserve_data(struct inode *inode,
266 struct extent_changeset **reserved, u64 start, u64 len);
267 int btrfs_qgroup_release_data(struct inode *inode, u64 start, u64 len);
268 int btrfs_qgroup_free_data(struct inode *inode,
269 struct extent_changeset *reserved, u64 start, u64 len);
270
271 int __btrfs_qgroup_reserve_meta(struct btrfs_root *root, int num_bytes,
272 enum btrfs_qgroup_rsv_type type, bool enforce);
273 /* Reserve metadata space for pertrans and prealloc type */
btrfs_qgroup_reserve_meta_pertrans(struct btrfs_root * root,int num_bytes,bool enforce)274 static inline int btrfs_qgroup_reserve_meta_pertrans(struct btrfs_root *root,
275 int num_bytes, bool enforce)
276 {
277 return __btrfs_qgroup_reserve_meta(root, num_bytes,
278 BTRFS_QGROUP_RSV_META_PERTRANS, enforce);
279 }
btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root * root,int num_bytes,bool enforce)280 static inline int btrfs_qgroup_reserve_meta_prealloc(struct btrfs_root *root,
281 int num_bytes, bool enforce)
282 {
283 return __btrfs_qgroup_reserve_meta(root, num_bytes,
284 BTRFS_QGROUP_RSV_META_PREALLOC, enforce);
285 }
286
287 void __btrfs_qgroup_free_meta(struct btrfs_root *root, int num_bytes,
288 enum btrfs_qgroup_rsv_type type);
289
290 /* Free per-transaction meta reservation for error handling */
btrfs_qgroup_free_meta_pertrans(struct btrfs_root * root,int num_bytes)291 static inline void btrfs_qgroup_free_meta_pertrans(struct btrfs_root *root,
292 int num_bytes)
293 {
294 __btrfs_qgroup_free_meta(root, num_bytes,
295 BTRFS_QGROUP_RSV_META_PERTRANS);
296 }
297
298 /* Pre-allocated meta reservation can be freed at need */
btrfs_qgroup_free_meta_prealloc(struct btrfs_root * root,int num_bytes)299 static inline void btrfs_qgroup_free_meta_prealloc(struct btrfs_root *root,
300 int num_bytes)
301 {
302 __btrfs_qgroup_free_meta(root, num_bytes,
303 BTRFS_QGROUP_RSV_META_PREALLOC);
304 }
305
306 /*
307 * Per-transaction meta reservation should be all freed at transaction commit
308 * time
309 */
310 void btrfs_qgroup_free_meta_all_pertrans(struct btrfs_root *root);
311
312 /*
313 * Convert @num_bytes of META_PREALLOCATED reservation to META_PERTRANS.
314 *
315 * This is called when preallocated meta reservation needs to be used.
316 * Normally after btrfs_join_transaction() call.
317 */
318 void btrfs_qgroup_convert_reserved_meta(struct btrfs_root *root, int num_bytes);
319
320 void btrfs_qgroup_check_reserved_leak(struct inode *inode);
321
322 #endif
323