1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _FS_CEPH_MDS_CLIENT_H
3 #define _FS_CEPH_MDS_CLIENT_H
4
5 #include <linux/completion.h>
6 #include <linux/kref.h>
7 #include <linux/list.h>
8 #include <linux/mutex.h>
9 #include <linux/rbtree.h>
10 #include <linux/spinlock.h>
11 #include <linux/refcount.h>
12 #include <linux/utsname.h>
13
14 #include <linux/ceph/types.h>
15 #include <linux/ceph/messenger.h>
16 #include <linux/ceph/mdsmap.h>
17 #include <linux/ceph/auth.h>
18
19 /* The first 8 bits are reserved for old ceph releases */
20 #define CEPHFS_FEATURE_MIMIC 8
21
22 #define CEPHFS_FEATURES_ALL { \
23 0, 1, 2, 3, 4, 5, 6, 7, \
24 CEPHFS_FEATURE_MIMIC, \
25 }
26
27 #define CEPHFS_FEATURES_CLIENT_SUPPORTED CEPHFS_FEATURES_ALL
28 #define CEPHFS_FEATURES_CLIENT_REQUIRED {}
29
30
31 /*
32 * Some lock dependencies:
33 *
34 * session->s_mutex
35 * mdsc->mutex
36 *
37 * mdsc->snap_rwsem
38 *
39 * ci->i_ceph_lock
40 * mdsc->snap_flush_lock
41 * mdsc->cap_delay_lock
42 *
43 */
44
45 struct ceph_fs_client;
46 struct ceph_cap;
47
48 /*
49 * parsed info about a single inode. pointers are into the encoded
50 * on-wire structures within the mds reply message payload.
51 */
52 struct ceph_mds_reply_info_in {
53 struct ceph_mds_reply_inode *in;
54 struct ceph_dir_layout dir_layout;
55 u32 symlink_len;
56 char *symlink;
57 u32 xattr_len;
58 char *xattr_data;
59 u64 inline_version;
60 u32 inline_len;
61 char *inline_data;
62 u32 pool_ns_len;
63 char *pool_ns_data;
64 u64 max_bytes;
65 u64 max_files;
66 };
67
68 struct ceph_mds_reply_dir_entry {
69 char *name;
70 u32 name_len;
71 struct ceph_mds_reply_lease *lease;
72 struct ceph_mds_reply_info_in inode;
73 loff_t offset;
74 };
75
76 /*
77 * parsed info about an mds reply, including information about
78 * either: 1) the target inode and/or its parent directory and dentry,
79 * and directory contents (for readdir results), or
80 * 2) the file range lock info (for fcntl F_GETLK results).
81 */
82 struct ceph_mds_reply_info_parsed {
83 struct ceph_mds_reply_head *head;
84
85 /* trace */
86 struct ceph_mds_reply_info_in diri, targeti;
87 struct ceph_mds_reply_dirfrag *dirfrag;
88 char *dname;
89 u32 dname_len;
90 struct ceph_mds_reply_lease *dlease;
91
92 /* extra */
93 union {
94 /* for fcntl F_GETLK results */
95 struct ceph_filelock *filelock_reply;
96
97 /* for readdir results */
98 struct {
99 struct ceph_mds_reply_dirfrag *dir_dir;
100 size_t dir_buf_size;
101 int dir_nr;
102 bool dir_end;
103 bool dir_complete;
104 bool hash_order;
105 bool offset_hash;
106 struct ceph_mds_reply_dir_entry *dir_entries;
107 };
108
109 /* for create results */
110 struct {
111 bool has_create_ino;
112 u64 ino;
113 };
114 };
115
116 /* encoded blob describing snapshot contexts for certain
117 operations (e.g., open) */
118 void *snapblob;
119 int snapblob_len;
120 };
121
122
123 /*
124 * cap releases are batched and sent to the MDS en masse.
125 *
126 * Account for per-message overhead of mds_cap_release header
127 * and __le32 for osd epoch barrier trailing field.
128 */
129 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) - \
130 sizeof(struct ceph_mds_cap_release)) / \
131 sizeof(struct ceph_mds_cap_item))
132
133
134 /*
135 * state associated with each MDS<->client session
136 */
137 enum {
138 CEPH_MDS_SESSION_NEW = 1,
139 CEPH_MDS_SESSION_OPENING = 2,
140 CEPH_MDS_SESSION_OPEN = 3,
141 CEPH_MDS_SESSION_HUNG = 4,
142 CEPH_MDS_SESSION_CLOSING = 5,
143 CEPH_MDS_SESSION_RESTARTING = 6,
144 CEPH_MDS_SESSION_RECONNECTING = 7,
145 CEPH_MDS_SESSION_REJECTED = 8,
146 };
147
148 struct ceph_mds_session {
149 struct ceph_mds_client *s_mdsc;
150 int s_mds;
151 int s_state;
152 unsigned long s_ttl; /* time until mds kills us */
153 u64 s_seq; /* incoming msg seq # */
154 struct mutex s_mutex; /* serialize session messages */
155
156 struct ceph_connection s_con;
157
158 struct ceph_auth_handshake s_auth;
159
160 /* protected by s_gen_ttl_lock */
161 spinlock_t s_gen_ttl_lock;
162 u32 s_cap_gen; /* inc each time we get mds stale msg */
163 unsigned long s_cap_ttl; /* when session caps expire */
164
165 /* protected by s_cap_lock */
166 spinlock_t s_cap_lock;
167 struct list_head s_caps; /* all caps issued by this session */
168 int s_nr_caps, s_trim_caps;
169 int s_num_cap_releases;
170 int s_cap_reconnect;
171 int s_readonly;
172 struct list_head s_cap_releases; /* waiting cap_release messages */
173 struct ceph_cap *s_cap_iterator;
174
175 /* protected by mutex */
176 struct list_head s_cap_flushing; /* inodes w/ flushing caps */
177 unsigned long s_renew_requested; /* last time we sent a renew req */
178 u64 s_renew_seq;
179
180 refcount_t s_ref;
181 struct list_head s_waiting; /* waiting requests */
182 struct list_head s_unsafe; /* unsafe requests */
183 };
184
185 /*
186 * modes of choosing which MDS to send a request to
187 */
188 enum {
189 USE_ANY_MDS,
190 USE_RANDOM_MDS,
191 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
192 };
193
194 struct ceph_mds_request;
195 struct ceph_mds_client;
196
197 /*
198 * request completion callback
199 */
200 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
201 struct ceph_mds_request *req);
202 /*
203 * wait for request completion callback
204 */
205 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
206 struct ceph_mds_request *req);
207
208 /*
209 * an in-flight mds request
210 */
211 struct ceph_mds_request {
212 u64 r_tid; /* transaction id */
213 struct rb_node r_node;
214 struct ceph_mds_client *r_mdsc;
215
216 int r_op; /* mds op code */
217
218 /* operation on what? */
219 struct inode *r_inode; /* arg1 */
220 struct dentry *r_dentry; /* arg1 */
221 struct dentry *r_old_dentry; /* arg2: rename from or link from */
222 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */
223 char *r_path1, *r_path2;
224 struct ceph_vino r_ino1, r_ino2;
225
226 struct inode *r_parent; /* parent dir inode */
227 struct inode *r_target_inode; /* resulting inode */
228
229 #define CEPH_MDS_R_DIRECT_IS_HASH (1) /* r_direct_hash is valid */
230 #define CEPH_MDS_R_ABORTED (2) /* call was aborted */
231 #define CEPH_MDS_R_GOT_UNSAFE (3) /* got an unsafe reply */
232 #define CEPH_MDS_R_GOT_SAFE (4) /* got a safe reply */
233 #define CEPH_MDS_R_GOT_RESULT (5) /* got a result */
234 #define CEPH_MDS_R_DID_PREPOPULATE (6) /* prepopulated readdir */
235 #define CEPH_MDS_R_PARENT_LOCKED (7) /* is r_parent->i_rwsem wlocked? */
236 unsigned long r_req_flags;
237
238 struct mutex r_fill_mutex;
239
240 union ceph_mds_request_args r_args;
241 int r_fmode; /* file mode, if expecting cap */
242 kuid_t r_uid;
243 kgid_t r_gid;
244 struct timespec64 r_stamp;
245
246 /* for choosing which mds to send this request to */
247 int r_direct_mode;
248 u32 r_direct_hash; /* choose dir frag based on this dentry hash */
249
250 /* data payload is used for xattr ops */
251 struct ceph_pagelist *r_pagelist;
252
253 /* what caps shall we drop? */
254 int r_inode_drop, r_inode_unless;
255 int r_dentry_drop, r_dentry_unless;
256 int r_old_dentry_drop, r_old_dentry_unless;
257 struct inode *r_old_inode;
258 int r_old_inode_drop, r_old_inode_unless;
259
260 struct ceph_msg *r_request; /* original request */
261 int r_request_release_offset;
262 struct ceph_msg *r_reply;
263 struct ceph_mds_reply_info_parsed r_reply_info;
264 struct page *r_locked_page;
265 int r_err;
266
267 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */
268 unsigned long r_started; /* start time to measure timeout against */
269 unsigned long r_request_started; /* start time for mds request only,
270 used to measure lease durations */
271
272 /* link unsafe requests to parent directory, for fsync */
273 struct inode *r_unsafe_dir;
274 struct list_head r_unsafe_dir_item;
275
276 /* unsafe requests that modify the target inode */
277 struct list_head r_unsafe_target_item;
278
279 struct ceph_mds_session *r_session;
280
281 int r_attempts; /* resend attempts */
282 int r_num_fwd; /* number of forward attempts */
283 int r_resend_mds; /* mds to resend to next, if any*/
284 u32 r_sent_on_mseq; /* cap mseq request was sent at*/
285
286 struct kref r_kref;
287 struct list_head r_wait;
288 struct completion r_completion;
289 struct completion r_safe_completion;
290 ceph_mds_request_callback_t r_callback;
291 ceph_mds_request_wait_callback_t r_wait_for_completion;
292 struct list_head r_unsafe_item; /* per-session unsafe list item */
293
294 long long r_dir_release_cnt;
295 long long r_dir_ordered_cnt;
296 int r_readdir_cache_idx;
297 u32 r_readdir_offset;
298
299 struct ceph_cap_reservation r_caps_reservation;
300 int r_num_caps;
301 };
302
303 struct ceph_pool_perm {
304 struct rb_node node;
305 int perm;
306 s64 pool;
307 size_t pool_ns_len;
308 char pool_ns[];
309 };
310
311 /*
312 * mds client state
313 */
314 struct ceph_mds_client {
315 struct ceph_fs_client *fsc;
316 struct mutex mutex; /* all nested structures */
317
318 struct ceph_mdsmap *mdsmap;
319 struct completion safe_umount_waiters;
320 wait_queue_head_t session_close_wq;
321 struct list_head waiting_for_map;
322 int mdsmap_err;
323
324 struct ceph_mds_session **sessions; /* NULL for mds if no session */
325 atomic_t num_sessions;
326 int max_sessions; /* len of s_mds_sessions */
327 int stopping; /* true if shutting down */
328
329 atomic64_t quotarealms_count; /* # realms with quota */
330
331 /*
332 * snap_rwsem will cover cap linkage into snaprealms, and
333 * realm snap contexts. (later, we can do per-realm snap
334 * contexts locks..) the empty list contains realms with no
335 * references (implying they contain no inodes with caps) that
336 * should be destroyed.
337 */
338 u64 last_snap_seq;
339 struct rw_semaphore snap_rwsem;
340 struct rb_root snap_realms;
341 struct list_head snap_empty;
342 spinlock_t snap_empty_lock; /* protect snap_empty */
343
344 u64 last_tid; /* most recent mds request */
345 u64 oldest_tid; /* oldest incomplete mds request,
346 excluding setfilelock requests */
347 struct rb_root request_tree; /* pending mds requests */
348 struct delayed_work delayed_work; /* delayed work */
349 unsigned long last_renew_caps; /* last time we renewed our caps */
350 struct list_head cap_delay_list; /* caps with delayed release */
351 spinlock_t cap_delay_lock; /* protects cap_delay_list */
352 struct list_head snap_flush_list; /* cap_snaps ready to flush */
353 spinlock_t snap_flush_lock;
354
355 u64 last_cap_flush_tid;
356 struct list_head cap_flush_list;
357 struct list_head cap_dirty; /* inodes with dirty caps */
358 struct list_head cap_dirty_migrating; /* ...that are migration... */
359 int num_cap_flushing; /* # caps we are flushing */
360 spinlock_t cap_dirty_lock; /* protects above items */
361 wait_queue_head_t cap_flushing_wq;
362
363 /*
364 * Cap reservations
365 *
366 * Maintain a global pool of preallocated struct ceph_caps, referenced
367 * by struct ceph_caps_reservations. This ensures that we preallocate
368 * memory needed to successfully process an MDS response. (If an MDS
369 * sends us cap information and we fail to process it, we will have
370 * problems due to the client and MDS being out of sync.)
371 *
372 * Reservations are 'owned' by a ceph_cap_reservation context.
373 */
374 spinlock_t caps_list_lock;
375 struct list_head caps_list; /* unused (reserved or
376 unreserved) */
377 int caps_total_count; /* total caps allocated */
378 int caps_use_count; /* in use */
379 int caps_reserve_count; /* unused, reserved */
380 int caps_avail_count; /* unused, unreserved */
381 int caps_min_count; /* keep at least this many
382 (unreserved) */
383 spinlock_t dentry_lru_lock;
384 struct list_head dentry_lru;
385 int num_dentry;
386
387 struct rw_semaphore pool_perm_rwsem;
388 struct rb_root pool_perm_tree;
389
390 char nodename[__NEW_UTS_LEN + 1];
391 };
392
393 extern const char *ceph_mds_op_name(int op);
394
395 extern struct ceph_mds_session *
396 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
397
398 static inline struct ceph_mds_session *
ceph_get_mds_session(struct ceph_mds_session * s)399 ceph_get_mds_session(struct ceph_mds_session *s)
400 {
401 refcount_inc(&s->s_ref);
402 return s;
403 }
404
405 extern const char *ceph_session_state_name(int s);
406
407 extern void ceph_put_mds_session(struct ceph_mds_session *s);
408
409 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
410 struct ceph_msg *msg, int mds);
411
412 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
413 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
414 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
415 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
416
417 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
418
419 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
420 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
421 struct inode *dir);
422 extern struct ceph_mds_request *
423 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
424 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
425 struct ceph_mds_request *req);
426 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
427 struct inode *dir,
428 struct ceph_mds_request *req);
ceph_mdsc_get_request(struct ceph_mds_request * req)429 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
430 {
431 kref_get(&req->r_kref);
432 }
433 extern void ceph_mdsc_release_request(struct kref *kref);
ceph_mdsc_put_request(struct ceph_mds_request * req)434 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
435 {
436 kref_put(&req->r_kref, ceph_mdsc_release_request);
437 }
438
439 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
440 struct ceph_mds_session *session);
441
442 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
443
444 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
445 int stop_on_nosnap);
446
447 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
448 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
449 struct inode *inode,
450 struct dentry *dentry, char action,
451 u32 seq);
452
453 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
454 struct ceph_msg *msg);
455 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
456 struct ceph_msg *msg);
457
458 extern struct ceph_mds_session *
459 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
460 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
461 struct ceph_mds_session *session);
462
463 extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
464 struct ceph_mds_session *session,
465 int max_caps);
466 #endif
467