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 #define CEPHFS_FEATURE_REPLY_ENCODING 9
22 #define CEPHFS_FEATURE_RECLAIM_CLIENT 10
23 #define CEPHFS_FEATURE_LAZY_CAP_WANTED 11
24 #define CEPHFS_FEATURE_MULTI_RECONNECT 12
25
26 #define CEPHFS_FEATURES_CLIENT_SUPPORTED { \
27 0, 1, 2, 3, 4, 5, 6, 7, \
28 CEPHFS_FEATURE_MIMIC, \
29 CEPHFS_FEATURE_REPLY_ENCODING, \
30 CEPHFS_FEATURE_LAZY_CAP_WANTED, \
31 CEPHFS_FEATURE_MULTI_RECONNECT, \
32 }
33 #define CEPHFS_FEATURES_CLIENT_REQUIRED {}
34
35
36 /*
37 * Some lock dependencies:
38 *
39 * session->s_mutex
40 * mdsc->mutex
41 *
42 * mdsc->snap_rwsem
43 *
44 * ci->i_ceph_lock
45 * mdsc->snap_flush_lock
46 * mdsc->cap_delay_lock
47 *
48 */
49
50 struct ceph_fs_client;
51 struct ceph_cap;
52
53 /*
54 * parsed info about a single inode. pointers are into the encoded
55 * on-wire structures within the mds reply message payload.
56 */
57 struct ceph_mds_reply_info_in {
58 struct ceph_mds_reply_inode *in;
59 struct ceph_dir_layout dir_layout;
60 u32 symlink_len;
61 char *symlink;
62 u32 xattr_len;
63 char *xattr_data;
64 u64 inline_version;
65 u32 inline_len;
66 char *inline_data;
67 u32 pool_ns_len;
68 char *pool_ns_data;
69 u64 max_bytes;
70 u64 max_files;
71 s32 dir_pin;
72 struct ceph_timespec btime;
73 struct ceph_timespec snap_btime;
74 u64 change_attr;
75 };
76
77 struct ceph_mds_reply_dir_entry {
78 char *name;
79 u32 name_len;
80 struct ceph_mds_reply_lease *lease;
81 struct ceph_mds_reply_info_in inode;
82 loff_t offset;
83 };
84
85 /*
86 * parsed info about an mds reply, including information about
87 * either: 1) the target inode and/or its parent directory and dentry,
88 * and directory contents (for readdir results), or
89 * 2) the file range lock info (for fcntl F_GETLK results).
90 */
91 struct ceph_mds_reply_info_parsed {
92 struct ceph_mds_reply_head *head;
93
94 /* trace */
95 struct ceph_mds_reply_info_in diri, targeti;
96 struct ceph_mds_reply_dirfrag *dirfrag;
97 char *dname;
98 u32 dname_len;
99 struct ceph_mds_reply_lease *dlease;
100
101 /* extra */
102 union {
103 /* for fcntl F_GETLK results */
104 struct ceph_filelock *filelock_reply;
105
106 /* for readdir results */
107 struct {
108 struct ceph_mds_reply_dirfrag *dir_dir;
109 size_t dir_buf_size;
110 int dir_nr;
111 bool dir_end;
112 bool dir_complete;
113 bool hash_order;
114 bool offset_hash;
115 struct ceph_mds_reply_dir_entry *dir_entries;
116 };
117
118 /* for create results */
119 struct {
120 bool has_create_ino;
121 u64 ino;
122 };
123 };
124
125 /* encoded blob describing snapshot contexts for certain
126 operations (e.g., open) */
127 void *snapblob;
128 int snapblob_len;
129 };
130
131
132 /*
133 * cap releases are batched and sent to the MDS en masse.
134 *
135 * Account for per-message overhead of mds_cap_release header
136 * and __le32 for osd epoch barrier trailing field.
137 */
138 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) - \
139 sizeof(struct ceph_mds_cap_release)) / \
140 sizeof(struct ceph_mds_cap_item))
141
142
143 /*
144 * state associated with each MDS<->client session
145 */
146 enum {
147 CEPH_MDS_SESSION_NEW = 1,
148 CEPH_MDS_SESSION_OPENING = 2,
149 CEPH_MDS_SESSION_OPEN = 3,
150 CEPH_MDS_SESSION_HUNG = 4,
151 CEPH_MDS_SESSION_RESTARTING = 5,
152 CEPH_MDS_SESSION_RECONNECTING = 6,
153 CEPH_MDS_SESSION_CLOSING = 7,
154 CEPH_MDS_SESSION_REJECTED = 8,
155 };
156
157 struct ceph_mds_session {
158 struct ceph_mds_client *s_mdsc;
159 int s_mds;
160 int s_state;
161 unsigned long s_ttl; /* time until mds kills us */
162 unsigned long s_features;
163 u64 s_seq; /* incoming msg seq # */
164 struct mutex s_mutex; /* serialize session messages */
165
166 struct ceph_connection s_con;
167
168 struct ceph_auth_handshake s_auth;
169
170 /* protected by s_gen_ttl_lock */
171 spinlock_t s_gen_ttl_lock;
172 u32 s_cap_gen; /* inc each time we get mds stale msg */
173 unsigned long s_cap_ttl; /* when session caps expire */
174
175 /* protected by s_cap_lock */
176 spinlock_t s_cap_lock;
177 struct list_head s_caps; /* all caps issued by this session */
178 struct ceph_cap *s_cap_iterator;
179 int s_nr_caps;
180 int s_num_cap_releases;
181 int s_cap_reconnect;
182 int s_readonly;
183 struct list_head s_cap_releases; /* waiting cap_release messages */
184 struct work_struct s_cap_release_work;
185
186 /* protected by mutex */
187 struct list_head s_cap_flushing; /* inodes w/ flushing caps */
188 unsigned long s_renew_requested; /* last time we sent a renew req */
189 u64 s_renew_seq;
190
191 refcount_t s_ref;
192 struct list_head s_waiting; /* waiting requests */
193 struct list_head s_unsafe; /* unsafe requests */
194 };
195
196 /*
197 * modes of choosing which MDS to send a request to
198 */
199 enum {
200 USE_ANY_MDS,
201 USE_RANDOM_MDS,
202 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
203 };
204
205 struct ceph_mds_request;
206 struct ceph_mds_client;
207
208 /*
209 * request completion callback
210 */
211 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
212 struct ceph_mds_request *req);
213 /*
214 * wait for request completion callback
215 */
216 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
217 struct ceph_mds_request *req);
218
219 /*
220 * an in-flight mds request
221 */
222 struct ceph_mds_request {
223 u64 r_tid; /* transaction id */
224 struct rb_node r_node;
225 struct ceph_mds_client *r_mdsc;
226
227 int r_op; /* mds op code */
228
229 /* operation on what? */
230 struct inode *r_inode; /* arg1 */
231 struct dentry *r_dentry; /* arg1 */
232 struct dentry *r_old_dentry; /* arg2: rename from or link from */
233 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */
234 char *r_path1, *r_path2;
235 struct ceph_vino r_ino1, r_ino2;
236
237 struct inode *r_parent; /* parent dir inode */
238 struct inode *r_target_inode; /* resulting inode */
239
240 #define CEPH_MDS_R_DIRECT_IS_HASH (1) /* r_direct_hash is valid */
241 #define CEPH_MDS_R_ABORTED (2) /* call was aborted */
242 #define CEPH_MDS_R_GOT_UNSAFE (3) /* got an unsafe reply */
243 #define CEPH_MDS_R_GOT_SAFE (4) /* got a safe reply */
244 #define CEPH_MDS_R_GOT_RESULT (5) /* got a result */
245 #define CEPH_MDS_R_DID_PREPOPULATE (6) /* prepopulated readdir */
246 #define CEPH_MDS_R_PARENT_LOCKED (7) /* is r_parent->i_rwsem wlocked? */
247 unsigned long r_req_flags;
248
249 struct mutex r_fill_mutex;
250
251 union ceph_mds_request_args r_args;
252 int r_fmode; /* file mode, if expecting cap */
253 kuid_t r_uid;
254 kgid_t r_gid;
255 struct timespec64 r_stamp;
256
257 /* for choosing which mds to send this request to */
258 int r_direct_mode;
259 u32 r_direct_hash; /* choose dir frag based on this dentry hash */
260
261 /* data payload is used for xattr ops */
262 struct ceph_pagelist *r_pagelist;
263
264 /* what caps shall we drop? */
265 int r_inode_drop, r_inode_unless;
266 int r_dentry_drop, r_dentry_unless;
267 int r_old_dentry_drop, r_old_dentry_unless;
268 struct inode *r_old_inode;
269 int r_old_inode_drop, r_old_inode_unless;
270
271 struct ceph_msg *r_request; /* original request */
272 int r_request_release_offset;
273 struct ceph_msg *r_reply;
274 struct ceph_mds_reply_info_parsed r_reply_info;
275 struct page *r_locked_page;
276 int r_err;
277
278 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */
279 unsigned long r_started; /* start time to measure timeout against */
280 unsigned long r_request_started; /* start time for mds request only,
281 used to measure lease durations */
282
283 /* link unsafe requests to parent directory, for fsync */
284 struct inode *r_unsafe_dir;
285 struct list_head r_unsafe_dir_item;
286
287 /* unsafe requests that modify the target inode */
288 struct list_head r_unsafe_target_item;
289
290 struct ceph_mds_session *r_session;
291
292 int r_attempts; /* resend attempts */
293 int r_num_fwd; /* number of forward attempts */
294 int r_resend_mds; /* mds to resend to next, if any*/
295 u32 r_sent_on_mseq; /* cap mseq request was sent at*/
296
297 struct kref r_kref;
298 struct list_head r_wait;
299 struct completion r_completion;
300 struct completion r_safe_completion;
301 ceph_mds_request_callback_t r_callback;
302 ceph_mds_request_wait_callback_t r_wait_for_completion;
303 struct list_head r_unsafe_item; /* per-session unsafe list item */
304
305 long long r_dir_release_cnt;
306 long long r_dir_ordered_cnt;
307 int r_readdir_cache_idx;
308 u32 r_readdir_offset;
309
310 struct ceph_cap_reservation r_caps_reservation;
311 int r_num_caps;
312 };
313
314 struct ceph_pool_perm {
315 struct rb_node node;
316 int perm;
317 s64 pool;
318 size_t pool_ns_len;
319 char pool_ns[];
320 };
321
322 struct ceph_snapid_map {
323 struct rb_node node;
324 struct list_head lru;
325 atomic_t ref;
326 u64 snap;
327 dev_t dev;
328 unsigned long last_used;
329 };
330
331 /*
332 * node for list of quotarealm inodes that are not visible from the filesystem
333 * mountpoint, but required to handle, e.g. quotas.
334 */
335 struct ceph_quotarealm_inode {
336 struct rb_node node;
337 u64 ino;
338 unsigned long timeout; /* last time a lookup failed for this inode */
339 struct mutex mutex;
340 struct inode *inode;
341 };
342
343 /*
344 * mds client state
345 */
346 struct ceph_mds_client {
347 struct ceph_fs_client *fsc;
348 struct mutex mutex; /* all nested structures */
349
350 struct ceph_mdsmap *mdsmap;
351 struct completion safe_umount_waiters;
352 wait_queue_head_t session_close_wq;
353 struct list_head waiting_for_map;
354 int mdsmap_err;
355
356 struct ceph_mds_session **sessions; /* NULL for mds if no session */
357 atomic_t num_sessions;
358 int max_sessions; /* len of s_mds_sessions */
359 int stopping; /* true if shutting down */
360
361 atomic64_t quotarealms_count; /* # realms with quota */
362 /*
363 * We keep a list of inodes we don't see in the mountpoint but that we
364 * need to track quota realms.
365 */
366 struct rb_root quotarealms_inodes;
367 struct mutex quotarealms_inodes_mutex;
368
369 /*
370 * snap_rwsem will cover cap linkage into snaprealms, and
371 * realm snap contexts. (later, we can do per-realm snap
372 * contexts locks..) the empty list contains realms with no
373 * references (implying they contain no inodes with caps) that
374 * should be destroyed.
375 */
376 u64 last_snap_seq;
377 struct rw_semaphore snap_rwsem;
378 struct rb_root snap_realms;
379 struct list_head snap_empty;
380 int num_snap_realms;
381 spinlock_t snap_empty_lock; /* protect snap_empty */
382
383 u64 last_tid; /* most recent mds request */
384 u64 oldest_tid; /* oldest incomplete mds request,
385 excluding setfilelock requests */
386 struct rb_root request_tree; /* pending mds requests */
387 struct delayed_work delayed_work; /* delayed work */
388 unsigned long last_renew_caps; /* last time we renewed our caps */
389 struct list_head cap_delay_list; /* caps with delayed release */
390 spinlock_t cap_delay_lock; /* protects cap_delay_list */
391 struct list_head snap_flush_list; /* cap_snaps ready to flush */
392 spinlock_t snap_flush_lock;
393
394 u64 last_cap_flush_tid;
395 struct list_head cap_flush_list;
396 struct list_head cap_dirty; /* inodes with dirty caps */
397 struct list_head cap_dirty_migrating; /* ...that are migration... */
398 int num_cap_flushing; /* # caps we are flushing */
399 spinlock_t cap_dirty_lock; /* protects above items */
400 wait_queue_head_t cap_flushing_wq;
401
402 struct work_struct cap_reclaim_work;
403 atomic_t cap_reclaim_pending;
404
405 /*
406 * Cap reservations
407 *
408 * Maintain a global pool of preallocated struct ceph_caps, referenced
409 * by struct ceph_caps_reservations. This ensures that we preallocate
410 * memory needed to successfully process an MDS response. (If an MDS
411 * sends us cap information and we fail to process it, we will have
412 * problems due to the client and MDS being out of sync.)
413 *
414 * Reservations are 'owned' by a ceph_cap_reservation context.
415 */
416 spinlock_t caps_list_lock;
417 struct list_head caps_list; /* unused (reserved or
418 unreserved) */
419 int caps_total_count; /* total caps allocated */
420 int caps_use_count; /* in use */
421 int caps_use_max; /* max used caps */
422 int caps_reserve_count; /* unused, reserved */
423 int caps_avail_count; /* unused, unreserved */
424 int caps_min_count; /* keep at least this many
425 (unreserved) */
426 spinlock_t dentry_list_lock;
427 struct list_head dentry_leases; /* fifo list */
428 struct list_head dentry_dir_leases; /* lru list */
429
430 spinlock_t snapid_map_lock;
431 struct rb_root snapid_map_tree;
432 struct list_head snapid_map_lru;
433
434 struct rw_semaphore pool_perm_rwsem;
435 struct rb_root pool_perm_tree;
436
437 char nodename[__NEW_UTS_LEN + 1];
438 };
439
440 extern const char *ceph_mds_op_name(int op);
441
442 extern struct ceph_mds_session *
443 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
444
445 static inline struct ceph_mds_session *
ceph_get_mds_session(struct ceph_mds_session * s)446 ceph_get_mds_session(struct ceph_mds_session *s)
447 {
448 refcount_inc(&s->s_ref);
449 return s;
450 }
451
452 extern const char *ceph_session_state_name(int s);
453
454 extern void ceph_put_mds_session(struct ceph_mds_session *s);
455
456 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
457 struct ceph_msg *msg, int mds);
458
459 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
460 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
461 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
462 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
463
464 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
465
466 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
467 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
468 struct inode *dir);
469 extern struct ceph_mds_request *
470 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
471 extern int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
472 struct inode *dir,
473 struct ceph_mds_request *req);
474 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
475 struct inode *dir,
476 struct ceph_mds_request *req);
ceph_mdsc_get_request(struct ceph_mds_request * req)477 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
478 {
479 kref_get(&req->r_kref);
480 }
481 extern void ceph_mdsc_release_request(struct kref *kref);
ceph_mdsc_put_request(struct ceph_mds_request * req)482 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
483 {
484 kref_put(&req->r_kref, ceph_mdsc_release_request);
485 }
486
487 extern void __ceph_queue_cap_release(struct ceph_mds_session *session,
488 struct ceph_cap *cap);
489 extern void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
490 struct ceph_mds_session *session);
491 extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
492 extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
493 extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
494 int (*cb)(struct inode *,
495 struct ceph_cap *, void *),
496 void *arg);
497 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
498
ceph_mdsc_free_path(char * path,int len)499 static inline void ceph_mdsc_free_path(char *path, int len)
500 {
501 if (path)
502 __putname(path - (PATH_MAX - 1 - len));
503 }
504
505 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
506 int stop_on_nosnap);
507
508 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
509 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
510 struct dentry *dentry, char action,
511 u32 seq);
512
513 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
514 struct ceph_msg *msg);
515 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
516 struct ceph_msg *msg);
517
518 extern struct ceph_mds_session *
519 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
520 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
521 struct ceph_mds_session *session);
522
523 extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
524 struct ceph_mds_session *session,
525 int max_caps);
526 #endif
527