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;
51 struct ceph_mds_reply_dir_entry {
54 struct ceph_mds_reply_lease *lease;
55 struct ceph_mds_reply_info_in inode;
60 * parsed info about an mds reply, including information about
61 * either: 1) the target inode and/or its parent directory and dentry,
62 * and directory contents (for readdir results), or
63 * 2) the file range lock info (for fcntl F_GETLK results).
65 struct ceph_mds_reply_info_parsed {
66 struct ceph_mds_reply_head *head;
69 struct ceph_mds_reply_info_in diri, targeti;
70 struct ceph_mds_reply_dirfrag *dirfrag;
73 struct ceph_mds_reply_lease *dlease;
77 /* for fcntl F_GETLK results */
78 struct ceph_filelock *filelock_reply;
80 /* for readdir results */
82 struct ceph_mds_reply_dirfrag *dir_dir;
88 struct ceph_mds_reply_dir_entry *dir_entries;
91 /* for create results */
98 /* encoded blob describing snapshot contexts for certain
99 operations (e.g., open) */
106 * cap releases are batched and sent to the MDS en masse.
108 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - \
109 sizeof(struct ceph_mds_cap_release)) / \
110 sizeof(struct ceph_mds_cap_item))
114 * state associated with each MDS<->client session
117 CEPH_MDS_SESSION_NEW = 1,
118 CEPH_MDS_SESSION_OPENING = 2,
119 CEPH_MDS_SESSION_OPEN = 3,
120 CEPH_MDS_SESSION_HUNG = 4,
121 CEPH_MDS_SESSION_CLOSING = 5,
122 CEPH_MDS_SESSION_RESTARTING = 6,
123 CEPH_MDS_SESSION_RECONNECTING = 7,
126 struct ceph_mds_session {
127 struct ceph_mds_client *s_mdsc;
130 unsigned long s_ttl; /* time until mds kills us */
131 u64 s_seq; /* incoming msg seq # */
132 struct mutex s_mutex; /* serialize session messages */
134 struct ceph_connection s_con;
136 struct ceph_auth_handshake s_auth;
138 /* protected by s_gen_ttl_lock */
139 spinlock_t s_gen_ttl_lock;
140 u32 s_cap_gen; /* inc each time we get mds stale msg */
141 unsigned long s_cap_ttl; /* when session caps expire */
143 /* protected by s_cap_lock */
144 spinlock_t s_cap_lock;
145 struct list_head s_caps; /* all caps issued by this session */
146 int s_nr_caps, s_trim_caps;
147 int s_num_cap_releases;
150 struct list_head s_cap_releases; /* waiting cap_release messages */
151 struct ceph_cap *s_cap_iterator;
153 /* protected by mutex */
154 struct list_head s_cap_flushing; /* inodes w/ flushing caps */
155 unsigned long s_renew_requested; /* last time we sent a renew req */
159 struct list_head s_waiting; /* waiting requests */
160 struct list_head s_unsafe; /* unsafe requests */
164 * modes of choosing which MDS to send a request to
169 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */
172 struct ceph_mds_request;
173 struct ceph_mds_client;
176 * request completion callback
178 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
179 struct ceph_mds_request *req);
181 * wait for request completion callback
183 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
184 struct ceph_mds_request *req);
187 * an in-flight mds request
189 struct ceph_mds_request {
190 u64 r_tid; /* transaction id */
191 struct rb_node r_node;
192 struct ceph_mds_client *r_mdsc;
194 int r_op; /* mds op code */
196 /* operation on what? */
197 struct inode *r_inode; /* arg1 */
198 struct dentry *r_dentry; /* arg1 */
199 struct dentry *r_old_dentry; /* arg2: rename from or link from */
200 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */
201 char *r_path1, *r_path2;
202 struct ceph_vino r_ino1, r_ino2;
204 struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */
205 struct inode *r_target_inode; /* resulting inode */
207 struct mutex r_fill_mutex;
209 union ceph_mds_request_args r_args;
210 int r_fmode; /* file mode, if expecting cap */
213 struct timespec r_stamp;
215 /* for choosing which mds to send this request to */
217 u32 r_direct_hash; /* choose dir frag based on this dentry hash */
218 bool r_direct_is_hash; /* true if r_direct_hash is valid */
220 /* data payload is used for xattr ops */
221 struct ceph_pagelist *r_pagelist;
223 /* what caps shall we drop? */
224 int r_inode_drop, r_inode_unless;
225 int r_dentry_drop, r_dentry_unless;
226 int r_old_dentry_drop, r_old_dentry_unless;
227 struct inode *r_old_inode;
228 int r_old_inode_drop, r_old_inode_unless;
230 struct ceph_msg *r_request; /* original request */
231 int r_request_release_offset;
232 struct ceph_msg *r_reply;
233 struct ceph_mds_reply_info_parsed r_reply_info;
234 struct page *r_locked_page;
238 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */
239 unsigned long r_started; /* start time to measure timeout against */
240 unsigned long r_request_started; /* start time for mds request only,
241 used to measure lease durations */
243 /* link unsafe requests to parent directory, for fsync */
244 struct inode *r_unsafe_dir;
245 struct list_head r_unsafe_dir_item;
247 /* unsafe requests that modify the target inode */
248 struct list_head r_unsafe_target_item;
250 struct ceph_mds_session *r_session;
252 int r_attempts; /* resend attempts */
253 int r_num_fwd; /* number of forward attempts */
254 int r_resend_mds; /* mds to resend to next, if any*/
255 u32 r_sent_on_mseq; /* cap mseq request was sent at*/
258 struct list_head r_wait;
259 struct completion r_completion;
260 struct completion r_safe_completion;
261 ceph_mds_request_callback_t r_callback;
262 ceph_mds_request_wait_callback_t r_wait_for_completion;
263 struct list_head r_unsafe_item; /* per-session unsafe list item */
264 bool r_got_unsafe, r_got_safe, r_got_result;
266 bool r_did_prepopulate;
267 long long r_dir_release_cnt;
268 long long r_dir_ordered_cnt;
269 int r_readdir_cache_idx;
270 u32 r_readdir_offset;
272 struct ceph_cap_reservation r_caps_reservation;
276 struct ceph_pool_perm {
287 struct ceph_mds_client {
288 struct ceph_fs_client *fsc;
289 struct mutex mutex; /* all nested structures */
291 struct ceph_mdsmap *mdsmap;
292 struct completion safe_umount_waiters;
293 wait_queue_head_t session_close_wq;
294 struct list_head waiting_for_map;
297 struct ceph_mds_session **sessions; /* NULL for mds if no session */
298 atomic_t num_sessions;
299 int max_sessions; /* len of s_mds_sessions */
300 int stopping; /* true if shutting down */
303 * snap_rwsem will cover cap linkage into snaprealms, and
304 * realm snap contexts. (later, we can do per-realm snap
305 * contexts locks..) the empty list contains realms with no
306 * references (implying they contain no inodes with caps) that
307 * should be destroyed.
310 struct rw_semaphore snap_rwsem;
311 struct rb_root snap_realms;
312 struct list_head snap_empty;
313 spinlock_t snap_empty_lock; /* protect snap_empty */
315 u64 last_tid; /* most recent mds request */
316 u64 oldest_tid; /* oldest incomplete mds request,
317 excluding setfilelock requests */
318 struct rb_root request_tree; /* pending mds requests */
319 struct delayed_work delayed_work; /* delayed work */
320 unsigned long last_renew_caps; /* last time we renewed our caps */
321 struct list_head cap_delay_list; /* caps with delayed release */
322 spinlock_t cap_delay_lock; /* protects cap_delay_list */
323 struct list_head snap_flush_list; /* cap_snaps ready to flush */
324 spinlock_t snap_flush_lock;
326 u64 last_cap_flush_tid;
327 struct list_head cap_flush_list;
328 struct list_head cap_dirty; /* inodes with dirty caps */
329 struct list_head cap_dirty_migrating; /* ...that are migration... */
330 int num_cap_flushing; /* # caps we are flushing */
331 spinlock_t cap_dirty_lock; /* protects above items */
332 wait_queue_head_t cap_flushing_wq;
337 * Maintain a global pool of preallocated struct ceph_caps, referenced
338 * by struct ceph_caps_reservations. This ensures that we preallocate
339 * memory needed to successfully process an MDS response. (If an MDS
340 * sends us cap information and we fail to process it, we will have
341 * problems due to the client and MDS being out of sync.)
343 * Reservations are 'owned' by a ceph_cap_reservation context.
345 spinlock_t caps_list_lock;
346 struct list_head caps_list; /* unused (reserved or
348 int caps_total_count; /* total caps allocated */
349 int caps_use_count; /* in use */
350 int caps_reserve_count; /* unused, reserved */
351 int caps_avail_count; /* unused, unreserved */
352 int caps_min_count; /* keep at least this many
354 spinlock_t dentry_lru_lock;
355 struct list_head dentry_lru;
358 struct rw_semaphore pool_perm_rwsem;
359 struct rb_root pool_perm_tree;
362 extern const char *ceph_mds_op_name(int op);
364 extern struct ceph_mds_session *
365 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
367 static inline struct ceph_mds_session *
368 ceph_get_mds_session(struct ceph_mds_session *s)
370 atomic_inc(&s->s_ref);
374 extern const char *ceph_session_state_name(int s);
376 extern void ceph_put_mds_session(struct ceph_mds_session *s);
378 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
379 struct ceph_msg *msg, int mds);
381 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
382 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
383 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
384 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
386 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
388 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
389 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
391 extern struct ceph_mds_request *
392 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
393 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
394 struct ceph_mds_request *req);
395 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
397 struct ceph_mds_request *req);
398 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
400 kref_get(&req->r_kref);
402 extern void ceph_mdsc_release_request(struct kref *kref);
403 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
405 kref_put(&req->r_kref, ceph_mdsc_release_request);
408 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc,
409 struct ceph_mds_session *session);
411 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
413 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
416 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
417 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
419 struct dentry *dentry, char action,
422 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
423 struct ceph_msg *msg);
424 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
425 struct ceph_msg *msg);
427 extern struct ceph_mds_session *
428 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
429 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
430 struct ceph_mds_session *session);