xref: /linux/fs/ceph/mds_client.h (revision b37042b2bb7cd751f03b73afb90364a418d870f4)
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 #include <linux/ktime.h>
14 
15 #include <linux/ceph/types.h>
16 #include <linux/ceph/messenger.h>
17 #include <linux/ceph/mdsmap.h>
18 #include <linux/ceph/auth.h>
19 
20 #include "metric.h"
21 #include "super.h"
22 
23 /* The first 8 bits are reserved for old ceph releases */
24 enum ceph_feature_type {
25 	CEPHFS_FEATURE_MIMIC = 8,
26 	CEPHFS_FEATURE_REPLY_ENCODING,
27 	CEPHFS_FEATURE_RECLAIM_CLIENT,
28 	CEPHFS_FEATURE_LAZY_CAP_WANTED,
29 	CEPHFS_FEATURE_MULTI_RECONNECT,
30 	CEPHFS_FEATURE_DELEG_INO,
31 	CEPHFS_FEATURE_METRIC_COLLECT,
32 	CEPHFS_FEATURE_ALTERNATE_NAME,
33 	CEPHFS_FEATURE_NOTIFY_SESSION_STATE,
34 
35 	CEPHFS_FEATURE_MAX = CEPHFS_FEATURE_NOTIFY_SESSION_STATE,
36 };
37 
38 #define CEPHFS_FEATURES_CLIENT_SUPPORTED {	\
39 	0, 1, 2, 3, 4, 5, 6, 7,			\
40 	CEPHFS_FEATURE_MIMIC,			\
41 	CEPHFS_FEATURE_REPLY_ENCODING,		\
42 	CEPHFS_FEATURE_LAZY_CAP_WANTED,		\
43 	CEPHFS_FEATURE_MULTI_RECONNECT,		\
44 	CEPHFS_FEATURE_DELEG_INO,		\
45 	CEPHFS_FEATURE_METRIC_COLLECT,		\
46 	CEPHFS_FEATURE_NOTIFY_SESSION_STATE,	\
47 }
48 
49 /*
50  * Some lock dependencies:
51  *
52  * session->s_mutex
53  *         mdsc->mutex
54  *
55  *         mdsc->snap_rwsem
56  *
57  *         ci->i_ceph_lock
58  *                 mdsc->snap_flush_lock
59  *                 mdsc->cap_delay_lock
60  *
61  */
62 
63 struct ceph_fs_client;
64 struct ceph_cap;
65 
66 /*
67  * parsed info about a single inode.  pointers are into the encoded
68  * on-wire structures within the mds reply message payload.
69  */
70 struct ceph_mds_reply_info_in {
71 	struct ceph_mds_reply_inode *in;
72 	struct ceph_dir_layout dir_layout;
73 	u32 symlink_len;
74 	char *symlink;
75 	u32 xattr_len;
76 	char *xattr_data;
77 	u64 inline_version;
78 	u32 inline_len;
79 	char *inline_data;
80 	u32 pool_ns_len;
81 	char *pool_ns_data;
82 	u64 max_bytes;
83 	u64 max_files;
84 	s32 dir_pin;
85 	struct ceph_timespec btime;
86 	struct ceph_timespec snap_btime;
87 	u64 rsnaps;
88 	u64 change_attr;
89 };
90 
91 struct ceph_mds_reply_dir_entry {
92 	char                          *name;
93 	u32                           name_len;
94 	struct ceph_mds_reply_lease   *lease;
95 	struct ceph_mds_reply_info_in inode;
96 	loff_t			      offset;
97 };
98 
99 struct ceph_mds_reply_xattr {
100 	char *xattr_value;
101 	size_t xattr_value_len;
102 };
103 
104 /*
105  * parsed info about an mds reply, including information about
106  * either: 1) the target inode and/or its parent directory and dentry,
107  * and directory contents (for readdir results), or
108  * 2) the file range lock info (for fcntl F_GETLK results).
109  */
110 struct ceph_mds_reply_info_parsed {
111 	struct ceph_mds_reply_head    *head;
112 
113 	/* trace */
114 	struct ceph_mds_reply_info_in diri, targeti;
115 	struct ceph_mds_reply_dirfrag *dirfrag;
116 	char                          *dname;
117 	u32                           dname_len;
118 	struct ceph_mds_reply_lease   *dlease;
119 	struct ceph_mds_reply_xattr   xattr_info;
120 
121 	/* extra */
122 	union {
123 		/* for fcntl F_GETLK results */
124 		struct ceph_filelock *filelock_reply;
125 
126 		/* for readdir results */
127 		struct {
128 			struct ceph_mds_reply_dirfrag *dir_dir;
129 			size_t			      dir_buf_size;
130 			int                           dir_nr;
131 			bool			      dir_end;
132 			bool			      dir_complete;
133 			bool			      hash_order;
134 			bool			      offset_hash;
135 			struct ceph_mds_reply_dir_entry  *dir_entries;
136 		};
137 
138 		/* for create results */
139 		struct {
140 			bool has_create_ino;
141 			u64 ino;
142 		};
143 	};
144 
145 	/* encoded blob describing snapshot contexts for certain
146 	   operations (e.g., open) */
147 	void *snapblob;
148 	int snapblob_len;
149 };
150 
151 
152 /*
153  * cap releases are batched and sent to the MDS en masse.
154  *
155  * Account for per-message overhead of mds_cap_release header
156  * and __le32 for osd epoch barrier trailing field.
157  */
158 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) -		\
159 				sizeof(struct ceph_mds_cap_release)) /	\
160 			        sizeof(struct ceph_mds_cap_item))
161 
162 
163 /*
164  * state associated with each MDS<->client session
165  */
166 enum {
167 	CEPH_MDS_SESSION_NEW = 1,
168 	CEPH_MDS_SESSION_OPENING = 2,
169 	CEPH_MDS_SESSION_OPEN = 3,
170 	CEPH_MDS_SESSION_HUNG = 4,
171 	CEPH_MDS_SESSION_RESTARTING = 5,
172 	CEPH_MDS_SESSION_RECONNECTING = 6,
173 	CEPH_MDS_SESSION_CLOSING = 7,
174 	CEPH_MDS_SESSION_CLOSED = 8,
175 	CEPH_MDS_SESSION_REJECTED = 9,
176 };
177 
178 struct ceph_mds_session {
179 	struct ceph_mds_client *s_mdsc;
180 	int               s_mds;
181 	int               s_state;
182 	unsigned long     s_ttl;      /* time until mds kills us */
183 	unsigned long	  s_features;
184 	u64               s_seq;      /* incoming msg seq # */
185 	struct mutex      s_mutex;    /* serialize session messages */
186 
187 	struct ceph_connection s_con;
188 
189 	struct ceph_auth_handshake s_auth;
190 
191 	atomic_t          s_cap_gen;  /* inc each time we get mds stale msg */
192 	unsigned long     s_cap_ttl;  /* when session caps expire. protected by s_mutex */
193 
194 	/* protected by s_cap_lock */
195 	spinlock_t        s_cap_lock;
196 	refcount_t        s_ref;
197 	struct list_head  s_caps;     /* all caps issued by this session */
198 	struct ceph_cap  *s_cap_iterator;
199 	int               s_nr_caps;
200 	int               s_num_cap_releases;
201 	int		  s_cap_reconnect;
202 	int		  s_readonly;
203 	struct list_head  s_cap_releases; /* waiting cap_release messages */
204 	struct work_struct s_cap_release_work;
205 
206 	/* See ceph_inode_info->i_dirty_item. */
207 	struct list_head  s_cap_dirty;	      /* inodes w/ dirty caps */
208 
209 	/* See ceph_inode_info->i_flushing_item. */
210 	struct list_head  s_cap_flushing;     /* inodes w/ flushing caps */
211 
212 	unsigned long     s_renew_requested; /* last time we sent a renew req */
213 	u64               s_renew_seq;
214 
215 	struct list_head  s_waiting;  /* waiting requests */
216 	struct list_head  s_unsafe;   /* unsafe requests */
217 	struct xarray	  s_delegated_inos;
218 };
219 
220 /*
221  * modes of choosing which MDS to send a request to
222  */
223 enum {
224 	USE_ANY_MDS,
225 	USE_RANDOM_MDS,
226 	USE_AUTH_MDS,   /* prefer authoritative mds for this metadata item */
227 };
228 
229 struct ceph_mds_request;
230 struct ceph_mds_client;
231 
232 /*
233  * request completion callback
234  */
235 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
236 					     struct ceph_mds_request *req);
237 /*
238  * wait for request completion callback
239  */
240 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
241 						 struct ceph_mds_request *req);
242 
243 /*
244  * an in-flight mds request
245  */
246 struct ceph_mds_request {
247 	u64 r_tid;                   /* transaction id */
248 	struct rb_node r_node;
249 	struct ceph_mds_client *r_mdsc;
250 
251 	struct kref       r_kref;
252 	int r_op;                    /* mds op code */
253 
254 	/* operation on what? */
255 	struct inode *r_inode;              /* arg1 */
256 	struct dentry *r_dentry;            /* arg1 */
257 	struct dentry *r_old_dentry;        /* arg2: rename from or link from */
258 	struct inode *r_old_dentry_dir;     /* arg2: old dentry's parent dir */
259 	char *r_path1, *r_path2;
260 	struct ceph_vino r_ino1, r_ino2;
261 
262 	struct inode *r_parent;		    /* parent dir inode */
263 	struct inode *r_target_inode;       /* resulting inode */
264 
265 #define CEPH_MDS_R_DIRECT_IS_HASH	(1) /* r_direct_hash is valid */
266 #define CEPH_MDS_R_ABORTED		(2) /* call was aborted */
267 #define CEPH_MDS_R_GOT_UNSAFE		(3) /* got an unsafe reply */
268 #define CEPH_MDS_R_GOT_SAFE		(4) /* got a safe reply */
269 #define CEPH_MDS_R_GOT_RESULT		(5) /* got a result */
270 #define CEPH_MDS_R_DID_PREPOPULATE	(6) /* prepopulated readdir */
271 #define CEPH_MDS_R_PARENT_LOCKED	(7) /* is r_parent->i_rwsem wlocked? */
272 #define CEPH_MDS_R_ASYNC		(8) /* async request */
273 	unsigned long	r_req_flags;
274 
275 	struct mutex r_fill_mutex;
276 
277 	union ceph_mds_request_args r_args;
278 	int r_fmode;        /* file mode, if expecting cap */
279 	int r_request_release_offset;
280 	const struct cred *r_cred;
281 	struct timespec64 r_stamp;
282 
283 	/* for choosing which mds to send this request to */
284 	int r_direct_mode;
285 	u32 r_direct_hash;      /* choose dir frag based on this dentry hash */
286 
287 	/* data payload is used for xattr ops */
288 	struct ceph_pagelist *r_pagelist;
289 
290 	/* what caps shall we drop? */
291 	int r_inode_drop, r_inode_unless;
292 	int r_dentry_drop, r_dentry_unless;
293 	int r_old_dentry_drop, r_old_dentry_unless;
294 	struct inode *r_old_inode;
295 	int r_old_inode_drop, r_old_inode_unless;
296 
297 	struct ceph_msg  *r_request;  /* original request */
298 	struct ceph_msg  *r_reply;
299 	struct ceph_mds_reply_info_parsed r_reply_info;
300 	int r_err;
301 	u32               r_readdir_offset;
302 
303 	struct page *r_locked_page;
304 	int r_dir_caps;
305 	int r_num_caps;
306 
307 	unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */
308 	unsigned long r_started;  /* start time to measure timeout against */
309 	unsigned long r_start_latency;  /* start time to measure latency */
310 	unsigned long r_end_latency;    /* finish time to measure latency */
311 	unsigned long r_request_started; /* start time for mds request only,
312 					    used to measure lease durations */
313 
314 	/* link unsafe requests to parent directory, for fsync */
315 	struct inode	*r_unsafe_dir;
316 	struct list_head r_unsafe_dir_item;
317 
318 	/* unsafe requests that modify the target inode */
319 	struct list_head r_unsafe_target_item;
320 
321 	struct ceph_mds_session *r_session;
322 
323 	int               r_attempts;   /* resend attempts */
324 	int               r_num_fwd;    /* number of forward attempts */
325 	int               r_resend_mds; /* mds to resend to next, if any*/
326 	u32               r_sent_on_mseq; /* cap mseq request was sent at*/
327 	u64		  r_deleg_ino;
328 
329 	struct list_head  r_wait;
330 	struct completion r_completion;
331 	struct completion r_safe_completion;
332 	ceph_mds_request_callback_t r_callback;
333 	struct list_head  r_unsafe_item;  /* per-session unsafe list item */
334 
335 	long long	  r_dir_release_cnt;
336 	long long	  r_dir_ordered_cnt;
337 	int		  r_readdir_cache_idx;
338 
339 	struct ceph_cap_reservation r_caps_reservation;
340 };
341 
342 struct ceph_pool_perm {
343 	struct rb_node node;
344 	int perm;
345 	s64 pool;
346 	size_t pool_ns_len;
347 	char pool_ns[];
348 };
349 
350 struct ceph_snapid_map {
351 	struct rb_node node;
352 	struct list_head lru;
353 	atomic_t ref;
354 	u64 snap;
355 	dev_t dev;
356 	unsigned long last_used;
357 };
358 
359 /*
360  * node for list of quotarealm inodes that are not visible from the filesystem
361  * mountpoint, but required to handle, e.g. quotas.
362  */
363 struct ceph_quotarealm_inode {
364 	struct rb_node node;
365 	u64 ino;
366 	unsigned long timeout; /* last time a lookup failed for this inode */
367 	struct mutex mutex;
368 	struct inode *inode;
369 };
370 
371 struct cap_wait {
372 	struct list_head	list;
373 	u64			ino;
374 	pid_t			tgid;
375 	int			need;
376 	int			want;
377 };
378 
379 /*
380  * mds client state
381  */
382 struct ceph_mds_client {
383 	struct ceph_fs_client  *fsc;
384 	struct mutex            mutex;         /* all nested structures */
385 
386 	struct ceph_mdsmap      *mdsmap;
387 	struct completion       safe_umount_waiters;
388 	wait_queue_head_t       session_close_wq;
389 	struct list_head        waiting_for_map;
390 	int 			mdsmap_err;
391 
392 	struct ceph_mds_session **sessions;    /* NULL for mds if no session */
393 	atomic_t		num_sessions;
394 	int                     max_sessions;  /* len of sessions array */
395 	int                     stopping;      /* true if shutting down */
396 
397 	atomic64_t		quotarealms_count; /* # realms with quota */
398 	/*
399 	 * We keep a list of inodes we don't see in the mountpoint but that we
400 	 * need to track quota realms.
401 	 */
402 	struct rb_root		quotarealms_inodes;
403 	struct mutex		quotarealms_inodes_mutex;
404 
405 	/*
406 	 * snap_rwsem will cover cap linkage into snaprealms, and
407 	 * realm snap contexts.  (later, we can do per-realm snap
408 	 * contexts locks..)  the empty list contains realms with no
409 	 * references (implying they contain no inodes with caps) that
410 	 * should be destroyed.
411 	 */
412 	u64			last_snap_seq;
413 	struct rw_semaphore     snap_rwsem;
414 	struct rb_root          snap_realms;
415 	struct list_head        snap_empty;
416 	int			num_snap_realms;
417 	spinlock_t              snap_empty_lock;  /* protect snap_empty */
418 
419 	u64                    last_tid;      /* most recent mds request */
420 	u64                    oldest_tid;    /* oldest incomplete mds request,
421 						 excluding setfilelock requests */
422 	struct rb_root         request_tree;  /* pending mds requests */
423 	struct delayed_work    delayed_work;  /* delayed work */
424 	unsigned long    last_renew_caps;  /* last time we renewed our caps */
425 	struct list_head cap_delay_list;   /* caps with delayed release */
426 	spinlock_t       cap_delay_lock;   /* protects cap_delay_list */
427 	struct list_head snap_flush_list;  /* cap_snaps ready to flush */
428 	spinlock_t       snap_flush_lock;
429 
430 	u64               last_cap_flush_tid;
431 	struct list_head  cap_flush_list;
432 	struct list_head  cap_dirty_migrating; /* ...that are migration... */
433 	int               num_cap_flushing; /* # caps we are flushing */
434 	spinlock_t        cap_dirty_lock;   /* protects above items */
435 	wait_queue_head_t cap_flushing_wq;
436 
437 	struct work_struct cap_reclaim_work;
438 	atomic_t	   cap_reclaim_pending;
439 
440 	/*
441 	 * Cap reservations
442 	 *
443 	 * Maintain a global pool of preallocated struct ceph_caps, referenced
444 	 * by struct ceph_caps_reservations.  This ensures that we preallocate
445 	 * memory needed to successfully process an MDS response.  (If an MDS
446 	 * sends us cap information and we fail to process it, we will have
447 	 * problems due to the client and MDS being out of sync.)
448 	 *
449 	 * Reservations are 'owned' by a ceph_cap_reservation context.
450 	 */
451 	spinlock_t	caps_list_lock;
452 	struct		list_head caps_list; /* unused (reserved or
453 						unreserved) */
454 	struct		list_head cap_wait_list;
455 	int		caps_total_count;    /* total caps allocated */
456 	int		caps_use_count;      /* in use */
457 	int		caps_use_max;	     /* max used caps */
458 	int		caps_reserve_count;  /* unused, reserved */
459 	int		caps_avail_count;    /* unused, unreserved */
460 	int		caps_min_count;      /* keep at least this many
461 						(unreserved) */
462 	spinlock_t	  dentry_list_lock;
463 	struct list_head  dentry_leases;     /* fifo list */
464 	struct list_head  dentry_dir_leases; /* lru list */
465 
466 	struct ceph_client_metric metric;
467 
468 	spinlock_t		snapid_map_lock;
469 	struct rb_root		snapid_map_tree;
470 	struct list_head	snapid_map_lru;
471 
472 	struct rw_semaphore     pool_perm_rwsem;
473 	struct rb_root		pool_perm_tree;
474 
475 	char nodename[__NEW_UTS_LEN + 1];
476 };
477 
478 extern const char *ceph_mds_op_name(int op);
479 
480 extern bool check_session_state(struct ceph_mds_session *s);
481 void inc_session_sequence(struct ceph_mds_session *s);
482 
483 extern struct ceph_mds_session *
484 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
485 
486 extern const char *ceph_session_state_name(int s);
487 
488 extern struct ceph_mds_session *
489 ceph_get_mds_session(struct ceph_mds_session *s);
490 extern void ceph_put_mds_session(struct ceph_mds_session *s);
491 
492 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
493 			     struct ceph_msg *msg, int mds);
494 
495 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
496 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
497 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
498 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
499 
500 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
501 
502 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
503 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
504 					   struct inode *dir);
505 extern struct ceph_mds_request *
506 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
507 extern int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
508 				    struct inode *dir,
509 				    struct ceph_mds_request *req);
510 int ceph_mdsc_wait_request(struct ceph_mds_client *mdsc,
511 			struct ceph_mds_request *req,
512 			ceph_mds_request_wait_callback_t wait_func);
513 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
514 				struct inode *dir,
515 				struct ceph_mds_request *req);
516 extern void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req);
517 extern void ceph_mdsc_release_dir_caps_no_check(struct ceph_mds_request *req);
518 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
519 {
520 	kref_get(&req->r_kref);
521 }
522 extern void ceph_mdsc_release_request(struct kref *kref);
523 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
524 {
525 	kref_put(&req->r_kref, ceph_mdsc_release_request);
526 }
527 
528 extern void send_flush_mdlog(struct ceph_mds_session *s);
529 extern void ceph_mdsc_iterate_sessions(struct ceph_mds_client *mdsc,
530 				       void (*cb)(struct ceph_mds_session *),
531 				       bool check_state);
532 extern struct ceph_msg *ceph_create_session_msg(u32 op, u64 seq);
533 extern void __ceph_queue_cap_release(struct ceph_mds_session *session,
534 				    struct ceph_cap *cap);
535 extern void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
536 				    struct ceph_mds_session *session);
537 extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
538 extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
539 extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
540 				     int (*cb)(struct inode *,
541 					       struct ceph_cap *, void *),
542 				     void *arg);
543 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
544 
545 static inline void ceph_mdsc_free_path(char *path, int len)
546 {
547 	if (!IS_ERR_OR_NULL(path))
548 		__putname(path - (PATH_MAX - 1 - len));
549 }
550 
551 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
552 				  int stop_on_nosnap);
553 
554 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
555 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
556 				     struct dentry *dentry, char action,
557 				     u32 seq);
558 
559 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
560 				    struct ceph_msg *msg);
561 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
562 				   struct ceph_msg *msg);
563 
564 extern struct ceph_mds_session *
565 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
566 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
567 					  struct ceph_mds_session *session);
568 
569 extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
570 			  struct ceph_mds_session *session,
571 			  int max_caps);
572 
573 static inline int ceph_wait_on_async_create(struct inode *inode)
574 {
575 	struct ceph_inode_info *ci = ceph_inode(inode);
576 
577 	return wait_on_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT,
578 			   TASK_KILLABLE);
579 }
580 
581 extern int ceph_wait_on_conflict_unlink(struct dentry *dentry);
582 extern u64 ceph_get_deleg_ino(struct ceph_mds_session *session);
583 extern int ceph_restore_deleg_ino(struct ceph_mds_session *session, u64 ino);
584 #endif
585