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>
12 #include "messenger.h"
16 * Some lock dependencies:
24 * mdsc->snap_flush_lock
25 * mdsc->cap_delay_lock
33 * parsed info about a single inode. pointers are into the encoded
34 * on-wire structures within the mds reply message payload.
36 struct ceph_mds_reply_info_in
{
37 struct ceph_mds_reply_inode
*in
;
45 * parsed info about an mds reply, including information about the
46 * target inode and/or its parent directory and dentry, and directory
47 * contents (for readdir results).
49 struct ceph_mds_reply_info_parsed
{
50 struct ceph_mds_reply_head
*head
;
52 struct ceph_mds_reply_info_in diri
, targeti
;
53 struct ceph_mds_reply_dirfrag
*dirfrag
;
56 struct ceph_mds_reply_lease
*dlease
;
58 struct ceph_mds_reply_dirfrag
*dir_dir
;
62 struct ceph_mds_reply_lease
**dir_dlease
;
63 struct ceph_mds_reply_info_in
*dir_in
;
64 u8 dir_complete
, dir_end
;
66 /* encoded blob describing snapshot contexts for certain
67 operations (e.g., open) */
74 * cap releases are batched and sent to the MDS en masse.
76 #define CEPH_CAPS_PER_RELEASE ((PAGE_CACHE_SIZE - \
77 sizeof(struct ceph_mds_cap_release)) / \
78 sizeof(struct ceph_mds_cap_item))
82 * state associated with each MDS<->client session
85 CEPH_MDS_SESSION_NEW
= 1,
86 CEPH_MDS_SESSION_OPENING
= 2,
87 CEPH_MDS_SESSION_OPEN
= 3,
88 CEPH_MDS_SESSION_HUNG
= 4,
89 CEPH_MDS_SESSION_CLOSING
= 5,
90 CEPH_MDS_SESSION_RESTARTING
= 6,
91 CEPH_MDS_SESSION_RECONNECTING
= 7,
94 struct ceph_mds_session
{
95 struct ceph_mds_client
*s_mdsc
;
98 unsigned long s_ttl
; /* time until mds kills us */
99 u64 s_seq
; /* incoming msg seq # */
100 struct mutex s_mutex
; /* serialize session messages */
102 struct ceph_connection s_con
;
104 struct ceph_authorizer
*s_authorizer
;
105 void *s_authorizer_buf
, *s_authorizer_reply_buf
;
106 size_t s_authorizer_buf_len
, s_authorizer_reply_buf_len
;
108 /* protected by s_cap_lock */
109 spinlock_t s_cap_lock
;
110 u32 s_cap_gen
; /* inc each time we get mds stale msg */
111 unsigned long s_cap_ttl
; /* when session caps expire */
112 struct list_head s_caps
; /* all caps issued by this session */
113 int s_nr_caps
, s_trim_caps
;
114 int s_num_cap_releases
;
115 struct list_head s_cap_releases
; /* waiting cap_release messages */
116 struct list_head s_cap_releases_done
; /* ready to send */
117 struct ceph_cap
*s_cap_iterator
;
119 /* protected by mutex */
120 struct list_head s_cap_flushing
; /* inodes w/ flushing caps */
121 struct list_head s_cap_snaps_flushing
;
122 unsigned long s_renew_requested
; /* last time we sent a renew req */
126 struct list_head s_waiting
; /* waiting requests */
127 struct list_head s_unsafe
; /* unsafe requests */
131 * modes of choosing which MDS to send a request to
136 USE_AUTH_MDS
, /* prefer authoritative mds for this metadata item */
139 struct ceph_mds_request
;
140 struct ceph_mds_client
;
143 * request completion callback
145 typedef void (*ceph_mds_request_callback_t
) (struct ceph_mds_client
*mdsc
,
146 struct ceph_mds_request
*req
);
149 * an in-flight mds request
151 struct ceph_mds_request
{
152 u64 r_tid
; /* transaction id */
153 struct rb_node r_node
;
154 struct ceph_mds_client
*r_mdsc
;
156 int r_op
; /* mds op code */
159 /* operation on what? */
160 struct inode
*r_inode
; /* arg1 */
161 struct dentry
*r_dentry
; /* arg1 */
162 struct dentry
*r_old_dentry
; /* arg2: rename from or link from */
163 char *r_path1
, *r_path2
;
164 struct ceph_vino r_ino1
, r_ino2
;
166 struct inode
*r_locked_dir
; /* dir (if any) i_mutex locked by vfs */
167 struct inode
*r_target_inode
; /* resulting inode */
169 struct mutex r_fill_mutex
;
171 union ceph_mds_request_args r_args
;
172 int r_fmode
; /* file mode, if expecting cap */
174 /* for choosing which mds to send this request to */
176 u32 r_direct_hash
; /* choose dir frag based on this dentry hash */
177 bool r_direct_is_hash
; /* true if r_direct_hash is valid */
179 /* data payload is used for xattr ops */
180 struct page
**r_pages
;
184 /* what caps shall we drop? */
185 int r_inode_drop
, r_inode_unless
;
186 int r_dentry_drop
, r_dentry_unless
;
187 int r_old_dentry_drop
, r_old_dentry_unless
;
188 struct inode
*r_old_inode
;
189 int r_old_inode_drop
, r_old_inode_unless
;
191 struct ceph_msg
*r_request
; /* original request */
192 int r_request_release_offset
;
193 struct ceph_msg
*r_reply
;
194 struct ceph_mds_reply_info_parsed r_reply_info
;
198 unsigned long r_timeout
; /* optional. jiffies */
199 unsigned long r_started
; /* start time to measure timeout against */
200 unsigned long r_request_started
; /* start time for mds request only,
201 used to measure lease durations */
203 /* link unsafe requests to parent directory, for fsync */
204 struct inode
*r_unsafe_dir
;
205 struct list_head r_unsafe_dir_item
;
207 struct ceph_mds_session
*r_session
;
209 int r_attempts
; /* resend attempts */
210 int r_num_fwd
; /* number of forward attempts */
211 int r_resend_mds
; /* mds to resend to next, if any*/
212 u32 r_sent_on_mseq
; /* cap mseq request was sent at*/
215 struct list_head r_wait
;
216 struct completion r_completion
;
217 struct completion r_safe_completion
;
218 ceph_mds_request_callback_t r_callback
;
219 struct list_head r_unsafe_item
; /* per-session unsafe list item */
220 bool r_got_unsafe
, r_got_safe
, r_got_result
;
222 bool r_did_prepopulate
;
223 u32 r_readdir_offset
;
225 struct ceph_cap_reservation r_caps_reservation
;
232 struct ceph_mds_client
{
233 struct ceph_client
*client
;
234 struct mutex mutex
; /* all nested structures */
236 struct ceph_mdsmap
*mdsmap
;
237 struct completion safe_umount_waiters
;
238 wait_queue_head_t session_close_wq
;
239 struct list_head waiting_for_map
;
241 struct ceph_mds_session
**sessions
; /* NULL for mds if no session */
242 int max_sessions
; /* len of s_mds_sessions */
243 int stopping
; /* true if shutting down */
246 * snap_rwsem will cover cap linkage into snaprealms, and
247 * realm snap contexts. (later, we can do per-realm snap
248 * contexts locks..) the empty list contains realms with no
249 * references (implying they contain no inodes with caps) that
250 * should be destroyed.
252 struct rw_semaphore snap_rwsem
;
253 struct rb_root snap_realms
;
254 struct list_head snap_empty
;
255 spinlock_t snap_empty_lock
; /* protect snap_empty */
257 u64 last_tid
; /* most recent mds request */
258 struct rb_root request_tree
; /* pending mds requests */
259 struct delayed_work delayed_work
; /* delayed work */
260 unsigned long last_renew_caps
; /* last time we renewed our caps */
261 struct list_head cap_delay_list
; /* caps with delayed release */
262 spinlock_t cap_delay_lock
; /* protects cap_delay_list */
263 struct list_head snap_flush_list
; /* cap_snaps ready to flush */
264 spinlock_t snap_flush_lock
;
267 struct list_head cap_dirty
; /* inodes with dirty caps */
268 int num_cap_flushing
; /* # caps we are flushing */
269 spinlock_t cap_dirty_lock
; /* protects above items */
270 wait_queue_head_t cap_flushing_wq
;
275 * Maintain a global pool of preallocated struct ceph_caps, referenced
276 * by struct ceph_caps_reservations. This ensures that we preallocate
277 * memory needed to successfully process an MDS response. (If an MDS
278 * sends us cap information and we fail to process it, we will have
279 * problems due to the client and MDS being out of sync.)
281 * Reservations are 'owned' by a ceph_cap_reservation context.
283 spinlock_t caps_list_lock
;
284 struct list_head caps_list
; /* unused (reserved or
286 int caps_total_count
; /* total caps allocated */
287 int caps_use_count
; /* in use */
288 int caps_reserve_count
; /* unused, reserved */
289 int caps_avail_count
; /* unused, unreserved */
290 int caps_min_count
; /* keep at least this many
293 #ifdef CONFIG_DEBUG_FS
294 struct dentry
*debugfs_file
;
297 spinlock_t dentry_lru_lock
;
298 struct list_head dentry_lru
;
302 extern const char *ceph_mds_op_name(int op
);
304 extern struct ceph_mds_session
*
305 __ceph_lookup_mds_session(struct ceph_mds_client
*, int mds
);
307 static inline struct ceph_mds_session
*
308 ceph_get_mds_session(struct ceph_mds_session
*s
)
310 atomic_inc(&s
->s_ref
);
314 extern void ceph_put_mds_session(struct ceph_mds_session
*s
);
316 extern int ceph_send_msg_mds(struct ceph_mds_client
*mdsc
,
317 struct ceph_msg
*msg
, int mds
);
319 extern int ceph_mdsc_init(struct ceph_mds_client
*mdsc
,
320 struct ceph_client
*client
);
321 extern void ceph_mdsc_close_sessions(struct ceph_mds_client
*mdsc
);
322 extern void ceph_mdsc_stop(struct ceph_mds_client
*mdsc
);
324 extern void ceph_mdsc_sync(struct ceph_mds_client
*mdsc
);
326 extern void ceph_mdsc_lease_release(struct ceph_mds_client
*mdsc
,
328 struct dentry
*dn
, int mask
);
330 extern void ceph_invalidate_dir_request(struct ceph_mds_request
*req
);
332 extern struct ceph_mds_request
*
333 ceph_mdsc_create_request(struct ceph_mds_client
*mdsc
, int op
, int mode
);
334 extern void ceph_mdsc_submit_request(struct ceph_mds_client
*mdsc
,
335 struct ceph_mds_request
*req
);
336 extern int ceph_mdsc_do_request(struct ceph_mds_client
*mdsc
,
338 struct ceph_mds_request
*req
);
339 static inline void ceph_mdsc_get_request(struct ceph_mds_request
*req
)
341 kref_get(&req
->r_kref
);
343 extern void ceph_mdsc_release_request(struct kref
*kref
);
344 static inline void ceph_mdsc_put_request(struct ceph_mds_request
*req
)
346 kref_put(&req
->r_kref
, ceph_mdsc_release_request
);
349 extern int ceph_add_cap_releases(struct ceph_mds_client
*mdsc
,
350 struct ceph_mds_session
*session
);
351 extern void ceph_send_cap_releases(struct ceph_mds_client
*mdsc
,
352 struct ceph_mds_session
*session
);
354 extern void ceph_mdsc_pre_umount(struct ceph_mds_client
*mdsc
);
356 extern char *ceph_mdsc_build_path(struct dentry
*dentry
, int *plen
, u64
*base
,
359 extern void __ceph_mdsc_drop_dentry_lease(struct dentry
*dentry
);
360 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session
*session
,
362 struct dentry
*dentry
, char action
,
365 extern void ceph_mdsc_handle_map(struct ceph_mds_client
*mdsc
,
366 struct ceph_msg
*msg
);
368 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client
*mdsc
,
369 struct ceph_mds_session
*session
);