1 #ifndef _FS_CEPH_MDS_CLIENT_H
2 #define _FS_CEPH_MDS_CLIENT_H
4 #include <linux/completion.h>
5 #include <linux/kref.h>
6 #include <linux/list.h>
7 #include <linux/mutex.h>
8 #include <linux/rbtree.h>
9 #include <linux/spinlock.h>
11 #include <linux/ceph/types.h>
12 #include <linux/ceph/messenger.h>
13 #include <linux/ceph/mdsmap.h>
14 #include <linux/ceph/auth.h>
17 * Some lock dependencies:
25 * mdsc->snap_flush_lock
26 * mdsc->cap_delay_lock
30 struct ceph_fs_client;
34 * parsed info about a single inode. pointers are into the encoded
35 * on-wire structures within the mds reply message payload.
37 struct ceph_mds_reply_info_in {
38 struct ceph_mds_reply_inode *in;
39 struct ceph_dir_layout dir_layout;
50 struct ceph_mds_reply_dir_entry {
53 struct ceph_mds_reply_lease *lease;
54 struct ceph_mds_reply_info_in inode;
58 * parsed info about an mds reply, including information about
59 * either: 1) the target inode and/or its parent directory and dentry,
60 * and directory contents (for readdir results), or
61 * 2) the file range lock info (for fcntl F_GETLK results).
63 struct ceph_mds_reply_info_parsed {
64 struct ceph_mds_reply_head *head;
67 struct ceph_mds_reply_info_in diri, targeti;
68 struct ceph_mds_reply_dirfrag *dirfrag;
71 struct ceph_mds_reply_lease *dlease;
75 /* for fcntl F_GETLK results */
76 struct ceph_filelock *filelock_reply;
78 /* for readdir results */
80 struct ceph_mds_reply_dirfrag *dir_dir;
83 bool dir_complete, dir_end;
84 struct ceph_mds_reply_dir_entry *dir_entries;
87 /* for create results */
94 /* encoded blob describing snapshot contexts for certain
95 operations (e.g., open) */
102 * cap releases are batched and sent to the MDS en masse.
104 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - \
105 sizeof(struct ceph_mds_cap_release)) / \
106 sizeof(struct ceph_mds_cap_item))
110 * state associated with each MDS<->client session
113 CEPH_MDS_SESSION_NEW = 1,
114 CEPH_MDS_SESSION_OPENING = 2,
115 CEPH_MDS_SESSION_OPEN = 3,
116 CEPH_MDS_SESSION_HUNG = 4,
117 CEPH_MDS_SESSION_CLOSING = 5,
118 CEPH_MDS_SESSION_RESTARTING = 6,
119 CEPH_MDS_SESSION_RECONNECTING = 7,
122 struct ceph_mds_session {
123 struct ceph_mds_client *s_mdsc;
126 unsigned long s_ttl; /* time until mds kills us */
127 u64 s_seq; /* incoming msg seq # */
128 struct mutex s_mutex; /* serialize session messages */
130 struct ceph_connection s_con;
132 struct ceph_auth_handshake s_auth;
134 /* protected by s_gen_ttl_lock */
135 spinlock_t s_gen_ttl_lock;
136 u32 s_cap_gen; /* inc each time we get mds stale msg */
137 unsigned long s_cap_ttl; /* when session caps expire */
139 /* protected by s_cap_lock */
140 spinlock_t s_cap_lock;
141 struct list_head s_caps; /* all caps issued by this session */
142 int s_nr_caps, s_trim_caps;
143 int s_num_cap_releases;
146 struct list_head s_cap_releases; /* waiting cap_release messages */
147 struct ceph_cap *s_cap_iterator;
149 /* protected by mutex */
150 struct list_head s_cap_flushing; /* inodes w/ flushing caps */
151 struct list_head s_cap_snaps_flushing;
152 unsigned long s_renew_requested; /* last time we sent a renew req */
156 struct list_head s_waiting; /* waiting requests */
157 struct list_head s_unsafe; /* unsafe requests */
161 * modes of choosing which MDS to send a request to
166 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
169 struct ceph_mds_request;
170 struct ceph_mds_client;
173 * request completion callback
175 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
176 struct ceph_mds_request *req);
178 * wait for request completion callback
180 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
181 struct ceph_mds_request *req);
184 * an in-flight mds request
186 struct ceph_mds_request {
187 u64 r_tid; /* transaction id */
188 struct rb_node r_node;
189 struct ceph_mds_client *r_mdsc;
191 int r_op; /* mds op code */
193 /* operation on what? */
194 struct inode *r_inode; /* arg1 */
195 struct dentry *r_dentry; /* arg1 */
196 struct dentry *r_old_dentry; /* arg2: rename from or link from */
197 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */
198 char *r_path1, *r_path2;
199 struct ceph_vino r_ino1, r_ino2;
201 struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */
202 struct inode *r_target_inode; /* resulting inode */
204 struct mutex r_fill_mutex;
206 union ceph_mds_request_args r_args;
207 int r_fmode; /* file mode, if expecting cap */
210 struct timespec r_stamp;
212 /* for choosing which mds to send this request to */
214 u32 r_direct_hash; /* choose dir frag based on this dentry hash */
215 bool r_direct_is_hash; /* true if r_direct_hash is valid */
217 /* data payload is used for xattr ops */
218 struct ceph_pagelist *r_pagelist;
220 /* what caps shall we drop? */
221 int r_inode_drop, r_inode_unless;
222 int r_dentry_drop, r_dentry_unless;
223 int r_old_dentry_drop, r_old_dentry_unless;
224 struct inode *r_old_inode;
225 int r_old_inode_drop, r_old_inode_unless;
227 struct ceph_msg *r_request; /* original request */
228 int r_request_release_offset;
229 struct ceph_msg *r_reply;
230 struct ceph_mds_reply_info_parsed r_reply_info;
231 struct page *r_locked_page;
235 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */
236 unsigned long r_started; /* start time to measure timeout against */
237 unsigned long r_request_started; /* start time for mds request only,
238 used to measure lease durations */
240 /* link unsafe requests to parent directory, for fsync */
241 struct inode *r_unsafe_dir;
242 struct list_head r_unsafe_dir_item;
244 /* unsafe requests that modify the target inode */
245 struct list_head r_unsafe_target_item;
247 struct ceph_mds_session *r_session;
249 int r_attempts; /* resend attempts */
250 int r_num_fwd; /* number of forward attempts */
251 int r_resend_mds; /* mds to resend to next, if any*/
252 u32 r_sent_on_mseq; /* cap mseq request was sent at*/
255 struct list_head r_wait;
256 struct completion r_completion;
257 struct completion r_safe_completion;
258 ceph_mds_request_callback_t r_callback;
259 ceph_mds_request_wait_callback_t r_wait_for_completion;
260 struct list_head r_unsafe_item; /* per-session unsafe list item */
261 bool r_got_unsafe, r_got_safe, r_got_result;
263 bool r_did_prepopulate;
264 long long r_dir_release_cnt;
265 long long r_dir_ordered_cnt;
266 int r_readdir_cache_idx;
267 u32 r_readdir_offset;
269 struct ceph_cap_reservation r_caps_reservation;
273 struct ceph_pool_perm {
282 struct ceph_mds_client {
283 struct ceph_fs_client *fsc;
284 struct mutex mutex; /* all nested structures */
286 struct ceph_mdsmap *mdsmap;
287 struct completion safe_umount_waiters;
288 wait_queue_head_t session_close_wq;
289 struct list_head waiting_for_map;
291 struct ceph_mds_session **sessions; /* NULL for mds if no session */
292 atomic_t num_sessions;
293 int max_sessions; /* len of s_mds_sessions */
294 int stopping; /* true if shutting down */
297 * snap_rwsem will cover cap linkage into snaprealms, and
298 * realm snap contexts. (later, we can do per-realm snap
299 * contexts locks..) the empty list contains realms with no
300 * references (implying they contain no inodes with caps) that
301 * should be destroyed.
304 struct rw_semaphore snap_rwsem;
305 struct rb_root snap_realms;
306 struct list_head snap_empty;
307 spinlock_t snap_empty_lock; /* protect snap_empty */
309 u64 last_tid; /* most recent mds request */
310 u64 oldest_tid; /* oldest incomplete mds request,
311 excluding setfilelock requests */
312 struct rb_root request_tree; /* pending mds requests */
313 struct delayed_work delayed_work; /* delayed work */
314 unsigned long last_renew_caps; /* last time we renewed our caps */
315 struct list_head cap_delay_list; /* caps with delayed release */
316 spinlock_t cap_delay_lock; /* protects cap_delay_list */
317 struct list_head snap_flush_list; /* cap_snaps ready to flush */
318 spinlock_t snap_flush_lock;
320 u64 last_cap_flush_tid;
321 struct rb_root cap_flush_tree;
322 struct list_head cap_dirty; /* inodes with dirty caps */
323 struct list_head cap_dirty_migrating; /* ...that are migration... */
324 int num_cap_flushing; /* # caps we are flushing */
325 spinlock_t cap_dirty_lock; /* protects above items */
326 wait_queue_head_t cap_flushing_wq;
331 * Maintain a global pool of preallocated struct ceph_caps, referenced
332 * by struct ceph_caps_reservations. This ensures that we preallocate
333 * memory needed to successfully process an MDS response. (If an MDS
334 * sends us cap information and we fail to process it, we will have
335 * problems due to the client and MDS being out of sync.)
337 * Reservations are 'owned' by a ceph_cap_reservation context.
339 spinlock_t caps_list_lock;
340 struct list_head caps_list; /* unused (reserved or
342 int caps_total_count; /* total caps allocated */
343 int caps_use_count; /* in use */
344 int caps_reserve_count; /* unused, reserved */
345 int caps_avail_count; /* unused, unreserved */
346 int caps_min_count; /* keep at least this many
348 spinlock_t dentry_lru_lock;
349 struct list_head dentry_lru;
352 struct rw_semaphore pool_perm_rwsem;
353 struct rb_root pool_perm_tree;
356 extern const char *ceph_mds_op_name(int op);
358 extern struct ceph_mds_session *
359 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
361 static inline struct ceph_mds_session *
362 ceph_get_mds_session(struct ceph_mds_session *s)
364 atomic_inc(&s->s_ref);
368 extern const char *ceph_session_state_name(int s);
370 extern void ceph_put_mds_session(struct ceph_mds_session *s);
372 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
373 struct ceph_msg *msg, int mds);
375 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
376 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
377 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
378 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
380 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
382 extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc,
386 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
387 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
389 extern struct ceph_mds_request *
390 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
391 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
392 struct ceph_mds_request *req);
393 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
395 struct ceph_mds_request *req);
396 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
398 kref_get(&req->r_kref);
400 extern void ceph_mdsc_release_request(struct kref *kref);
401 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
403 kref_put(&req->r_kref, ceph_mdsc_release_request);
406 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
407 struct ceph_mds_session *session);
409 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
411 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
414 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
415 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
417 struct dentry *dentry, char action,
420 extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc,
421 struct ceph_msg *msg);
423 extern struct ceph_mds_session *
424 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
425 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
426 struct ceph_mds_session *session);