mds_client.h revision d095559c
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 */
24enum 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
33	CEPHFS_FEATURE_MAX = CEPHFS_FEATURE_METRIC_COLLECT,
34};
35
36/*
37 * This will always have the highest feature bit value
38 * as the last element of the array.
39 */
40#define CEPHFS_FEATURES_CLIENT_SUPPORTED {	\
41	0, 1, 2, 3, 4, 5, 6, 7,			\
42	CEPHFS_FEATURE_MIMIC,			\
43	CEPHFS_FEATURE_REPLY_ENCODING,		\
44	CEPHFS_FEATURE_LAZY_CAP_WANTED,		\
45	CEPHFS_FEATURE_MULTI_RECONNECT,		\
46	CEPHFS_FEATURE_DELEG_INO,		\
47	CEPHFS_FEATURE_METRIC_COLLECT,		\
48						\
49	CEPHFS_FEATURE_MAX,			\
50}
51#define CEPHFS_FEATURES_CLIENT_REQUIRED {}
52
53/*
54 * Some lock dependencies:
55 *
56 * session->s_mutex
57 *         mdsc->mutex
58 *
59 *         mdsc->snap_rwsem
60 *
61 *         ci->i_ceph_lock
62 *                 mdsc->snap_flush_lock
63 *                 mdsc->cap_delay_lock
64 *
65 */
66
67struct ceph_fs_client;
68struct ceph_cap;
69
70/*
71 * parsed info about a single inode.  pointers are into the encoded
72 * on-wire structures within the mds reply message payload.
73 */
74struct ceph_mds_reply_info_in {
75	struct ceph_mds_reply_inode *in;
76	struct ceph_dir_layout dir_layout;
77	u32 symlink_len;
78	char *symlink;
79	u32 xattr_len;
80	char *xattr_data;
81	u64 inline_version;
82	u32 inline_len;
83	char *inline_data;
84	u32 pool_ns_len;
85	char *pool_ns_data;
86	u64 max_bytes;
87	u64 max_files;
88	s32 dir_pin;
89	struct ceph_timespec btime;
90	struct ceph_timespec snap_btime;
91	u64 rsnaps;
92	u64 change_attr;
93};
94
95struct ceph_mds_reply_dir_entry {
96	char                          *name;
97	u32                           name_len;
98	struct ceph_mds_reply_lease   *lease;
99	struct ceph_mds_reply_info_in inode;
100	loff_t			      offset;
101};
102
103/*
104 * parsed info about an mds reply, including information about
105 * either: 1) the target inode and/or its parent directory and dentry,
106 * and directory contents (for readdir results), or
107 * 2) the file range lock info (for fcntl F_GETLK results).
108 */
109struct ceph_mds_reply_info_parsed {
110	struct ceph_mds_reply_head    *head;
111
112	/* trace */
113	struct ceph_mds_reply_info_in diri, targeti;
114	struct ceph_mds_reply_dirfrag *dirfrag;
115	char                          *dname;
116	u32                           dname_len;
117	struct ceph_mds_reply_lease   *dlease;
118
119	/* extra */
120	union {
121		/* for fcntl F_GETLK results */
122		struct ceph_filelock *filelock_reply;
123
124		/* for readdir results */
125		struct {
126			struct ceph_mds_reply_dirfrag *dir_dir;
127			size_t			      dir_buf_size;
128			int                           dir_nr;
129			bool			      dir_end;
130			bool			      dir_complete;
131			bool			      hash_order;
132			bool			      offset_hash;
133			struct ceph_mds_reply_dir_entry  *dir_entries;
134		};
135
136		/* for create results */
137		struct {
138			bool has_create_ino;
139			u64 ino;
140		};
141	};
142
143	/* encoded blob describing snapshot contexts for certain
144	   operations (e.g., open) */
145	void *snapblob;
146	int snapblob_len;
147};
148
149
150/*
151 * cap releases are batched and sent to the MDS en masse.
152 *
153 * Account for per-message overhead of mds_cap_release header
154 * and __le32 for osd epoch barrier trailing field.
155 */
156#define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) -		\
157				sizeof(struct ceph_mds_cap_release)) /	\
158			        sizeof(struct ceph_mds_cap_item))
159
160
161/*
162 * state associated with each MDS<->client session
163 */
164enum {
165	CEPH_MDS_SESSION_NEW = 1,
166	CEPH_MDS_SESSION_OPENING = 2,
167	CEPH_MDS_SESSION_OPEN = 3,
168	CEPH_MDS_SESSION_HUNG = 4,
169	CEPH_MDS_SESSION_RESTARTING = 5,
170	CEPH_MDS_SESSION_RECONNECTING = 6,
171	CEPH_MDS_SESSION_CLOSING = 7,
172	CEPH_MDS_SESSION_CLOSED = 8,
173	CEPH_MDS_SESSION_REJECTED = 9,
174};
175
176struct ceph_mds_session {
177	struct ceph_mds_client *s_mdsc;
178	int               s_mds;
179	int               s_state;
180	unsigned long     s_ttl;      /* time until mds kills us */
181	unsigned long	  s_features;
182	u64               s_seq;      /* incoming msg seq # */
183	struct mutex      s_mutex;    /* serialize session messages */
184
185	struct ceph_connection s_con;
186
187	struct ceph_auth_handshake s_auth;
188
189	atomic_t          s_cap_gen;  /* inc each time we get mds stale msg */
190	unsigned long     s_cap_ttl;  /* when session caps expire. protected by s_mutex */
191
192	/* protected by s_cap_lock */
193	spinlock_t        s_cap_lock;
194	refcount_t        s_ref;
195	struct list_head  s_caps;     /* all caps issued by this session */
196	struct ceph_cap  *s_cap_iterator;
197	int               s_nr_caps;
198	int               s_num_cap_releases;
199	int		  s_cap_reconnect;
200	int		  s_readonly;
201	struct list_head  s_cap_releases; /* waiting cap_release messages */
202	struct work_struct s_cap_release_work;
203
204	/* See ceph_inode_info->i_dirty_item. */
205	struct list_head  s_cap_dirty;	      /* inodes w/ dirty caps */
206
207	/* See ceph_inode_info->i_flushing_item. */
208	struct list_head  s_cap_flushing;     /* inodes w/ flushing caps */
209
210	unsigned long     s_renew_requested; /* last time we sent a renew req */
211	u64               s_renew_seq;
212
213	struct list_head  s_waiting;  /* waiting requests */
214	struct list_head  s_unsafe;   /* unsafe requests */
215	struct xarray	  s_delegated_inos;
216};
217
218/*
219 * modes of choosing which MDS to send a request to
220 */
221enum {
222	USE_ANY_MDS,
223	USE_RANDOM_MDS,
224	USE_AUTH_MDS,   /* prefer authoritative mds for this metadata item */
225};
226
227struct ceph_mds_request;
228struct ceph_mds_client;
229
230/*
231 * request completion callback
232 */
233typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
234					     struct ceph_mds_request *req);
235/*
236 * wait for request completion callback
237 */
238typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
239						 struct ceph_mds_request *req);
240
241/*
242 * an in-flight mds request
243 */
244struct ceph_mds_request {
245	u64 r_tid;                   /* transaction id */
246	struct rb_node r_node;
247	struct ceph_mds_client *r_mdsc;
248
249	struct kref       r_kref;
250	int r_op;                    /* mds op code */
251
252	/* operation on what? */
253	struct inode *r_inode;              /* arg1 */
254	struct dentry *r_dentry;            /* arg1 */
255	struct dentry *r_old_dentry;        /* arg2: rename from or link from */
256	struct inode *r_old_dentry_dir;     /* arg2: old dentry's parent dir */
257	char *r_path1, *r_path2;
258	struct ceph_vino r_ino1, r_ino2;
259
260	struct inode *r_parent;		    /* parent dir inode */
261	struct inode *r_target_inode;       /* resulting inode */
262
263#define CEPH_MDS_R_DIRECT_IS_HASH	(1) /* r_direct_hash is valid */
264#define CEPH_MDS_R_ABORTED		(2) /* call was aborted */
265#define CEPH_MDS_R_GOT_UNSAFE		(3) /* got an unsafe reply */
266#define CEPH_MDS_R_GOT_SAFE		(4) /* got a safe reply */
267#define CEPH_MDS_R_GOT_RESULT		(5) /* got a result */
268#define CEPH_MDS_R_DID_PREPOPULATE	(6) /* prepopulated readdir */
269#define CEPH_MDS_R_PARENT_LOCKED	(7) /* is r_parent->i_rwsem wlocked? */
270#define CEPH_MDS_R_ASYNC		(8) /* async request */
271	unsigned long	r_req_flags;
272
273	struct mutex r_fill_mutex;
274
275	union ceph_mds_request_args r_args;
276	int r_fmode;        /* file mode, if expecting cap */
277	const struct cred *r_cred;
278	int r_request_release_offset;
279	struct timespec64 r_stamp;
280
281	/* for choosing which mds to send this request to */
282	int r_direct_mode;
283	u32 r_direct_hash;      /* choose dir frag based on this dentry hash */
284
285	/* data payload is used for xattr ops */
286	struct ceph_pagelist *r_pagelist;
287
288	/* what caps shall we drop? */
289	int r_inode_drop, r_inode_unless;
290	int r_dentry_drop, r_dentry_unless;
291	int r_old_dentry_drop, r_old_dentry_unless;
292	struct inode *r_old_inode;
293	int r_old_inode_drop, r_old_inode_unless;
294
295	struct ceph_msg  *r_request;  /* original request */
296	struct ceph_msg  *r_reply;
297	struct ceph_mds_reply_info_parsed r_reply_info;
298	int r_err;
299
300
301	struct page *r_locked_page;
302	int r_dir_caps;
303	int r_num_caps;
304	u32               r_readdir_offset;
305
306	unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */
307	unsigned long r_started;  /* start time to measure timeout against */
308	unsigned long r_start_latency;  /* start time to measure latency */
309	unsigned long r_end_latency;    /* finish time to measure latency */
310	unsigned long r_request_started; /* start time for mds request only,
311					    used to measure lease durations */
312
313	/* link unsafe requests to parent directory, for fsync */
314	struct inode	*r_unsafe_dir;
315	struct list_head r_unsafe_dir_item;
316
317	/* unsafe requests that modify the target inode */
318	struct list_head r_unsafe_target_item;
319
320	struct ceph_mds_session *r_session;
321
322	int               r_attempts;   /* resend attempts */
323	int               r_num_fwd;    /* number of forward attempts */
324	int               r_resend_mds; /* mds to resend to next, if any*/
325	u32               r_sent_on_mseq; /* cap mseq request was sent at*/
326	u64		  r_deleg_ino;
327
328	struct list_head  r_wait;
329	struct completion r_completion;
330	struct completion r_safe_completion;
331	ceph_mds_request_callback_t r_callback;
332	ceph_mds_request_wait_callback_t r_wait_for_completion;
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
342struct 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
350struct 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 */
363struct 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
371struct 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 */
382struct 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
478extern const char *ceph_mds_op_name(int op);
479
480extern bool check_session_state(struct ceph_mds_session *s);
481void inc_session_sequence(struct ceph_mds_session *s);
482
483extern struct ceph_mds_session *
484__ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
485
486extern const char *ceph_session_state_name(int s);
487
488extern struct ceph_mds_session *
489ceph_get_mds_session(struct ceph_mds_session *s);
490extern void ceph_put_mds_session(struct ceph_mds_session *s);
491
492extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
493			     struct ceph_msg *msg, int mds);
494
495extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
496extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
497extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
498extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
499
500extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
501
502extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
503extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
504					   struct inode *dir);
505extern struct ceph_mds_request *
506ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
507extern int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
508				    struct inode *dir,
509				    struct ceph_mds_request *req);
510extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
511				struct inode *dir,
512				struct ceph_mds_request *req);
513extern void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req);
514extern void ceph_mdsc_release_dir_caps_no_check(struct ceph_mds_request *req);
515static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
516{
517	kref_get(&req->r_kref);
518}
519extern void ceph_mdsc_release_request(struct kref *kref);
520static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
521{
522	kref_put(&req->r_kref, ceph_mdsc_release_request);
523}
524
525extern void send_flush_mdlog(struct ceph_mds_session *s);
526extern void ceph_mdsc_iterate_sessions(struct ceph_mds_client *mdsc,
527				       void (*cb)(struct ceph_mds_session *),
528				       bool check_state);
529extern struct ceph_msg *ceph_create_session_msg(u32 op, u64 seq);
530extern void __ceph_queue_cap_release(struct ceph_mds_session *session,
531				    struct ceph_cap *cap);
532extern void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
533				    struct ceph_mds_session *session);
534extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
535extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
536extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
537				     int (*cb)(struct inode *,
538					       struct ceph_cap *, void *),
539				     void *arg);
540extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
541
542static inline void ceph_mdsc_free_path(char *path, int len)
543{
544	if (!IS_ERR_OR_NULL(path))
545		__putname(path - (PATH_MAX - 1 - len));
546}
547
548extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
549				  int stop_on_nosnap);
550
551extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
552extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
553				     struct dentry *dentry, char action,
554				     u32 seq);
555
556extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
557				    struct ceph_msg *msg);
558extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
559				   struct ceph_msg *msg);
560
561extern struct ceph_mds_session *
562ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
563extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
564					  struct ceph_mds_session *session);
565
566extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
567			  struct ceph_mds_session *session,
568			  int max_caps);
569
570static inline int ceph_wait_on_async_create(struct inode *inode)
571{
572	struct ceph_inode_info *ci = ceph_inode(inode);
573
574	return wait_on_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT,
575			   TASK_INTERRUPTIBLE);
576}
577
578extern u64 ceph_get_deleg_ino(struct ceph_mds_session *session);
579extern int ceph_restore_deleg_ino(struct ceph_mds_session *session, u64 ino);
580#endif
581