1 #ifndef _FS_CEPH_MDS_CLIENT_H
2 #define _FS_CEPH_MDS_CLIENT_H
4 #include <linux/completion.h>
5 #include <linux/list.h>
6 #include <linux/mutex.h>
7 #include <linux/radix-tree.h>
8 #include <linux/spinlock.h>
11 #include "messenger.h"
15 * Some lock dependencies:
23 * mdsc->snap_flush_lock
24 * mdsc->cap_delay_lock
32 * parsed info about a single inode. pointers are into the encoded
33 * on-wire structures within the mds reply message payload.
35 struct ceph_mds_reply_info_in
{
36 struct ceph_mds_reply_inode
*in
;
44 * parsed info about an mds reply, including information about the
45 * target inode and/or its parent directory and dentry, and directory
46 * contents (for readdir results).
48 struct ceph_mds_reply_info_parsed
{
49 struct ceph_mds_reply_head
*head
;
51 struct ceph_mds_reply_info_in diri
, targeti
;
52 struct ceph_mds_reply_dirfrag
*dirfrag
;
55 struct ceph_mds_reply_lease
*dlease
;
57 struct ceph_mds_reply_dirfrag
*dir_dir
;
61 struct ceph_mds_reply_lease
**dir_dlease
;
62 struct ceph_mds_reply_info_in
*dir_in
;
63 u8 dir_complete
, dir_end
;
65 /* encoded blob describing snapshot contexts for certain
66 operations (e.g., open) */
73 * cap releases are batched and sent to the MDS en masse.
75 #define CEPH_CAPS_PER_RELEASE ((PAGE_CACHE_SIZE - \
76 sizeof(struct ceph_mds_cap_release)) / \
77 sizeof(struct ceph_mds_cap_item))
81 * state associated with each MDS<->client session
84 CEPH_MDS_SESSION_NEW
= 1,
85 CEPH_MDS_SESSION_OPENING
= 2,
86 CEPH_MDS_SESSION_OPEN
= 3,
87 CEPH_MDS_SESSION_HUNG
= 4,
88 CEPH_MDS_SESSION_CLOSING
= 5,
89 CEPH_MDS_SESSION_RESTARTING
= 6,
90 CEPH_MDS_SESSION_RECONNECTING
= 7,
93 struct ceph_mds_session
{
94 struct ceph_mds_client
*s_mdsc
;
97 unsigned long s_ttl
; /* time until mds kills us */
98 u64 s_seq
; /* incoming msg seq # */
99 struct mutex s_mutex
; /* serialize session messages */
101 struct ceph_connection s_con
;
103 /* protected by s_cap_lock */
104 spinlock_t s_cap_lock
;
105 u32 s_cap_gen
; /* inc each time we get mds stale msg */
106 unsigned long s_cap_ttl
; /* when session caps expire */
107 struct list_head s_caps
; /* all caps issued by this session */
108 int s_nr_caps
, s_trim_caps
;
109 int s_num_cap_releases
;
110 struct list_head s_cap_releases
; /* waiting cap_release messages */
111 struct list_head s_cap_releases_done
; /* ready to send */
113 /* protected by mutex */
114 struct list_head s_cap_flushing
; /* inodes w/ flushing caps */
115 struct list_head s_cap_snaps_flushing
;
116 unsigned long s_renew_requested
; /* last time we sent a renew req */
120 struct list_head s_waiting
; /* waiting requests */
121 struct list_head s_unsafe
; /* unsafe requests */
125 * modes of choosing which MDS to send a request to
130 USE_AUTH_MDS
, /* prefer authoritative mds for this metadata item */
133 struct ceph_mds_request
;
134 struct ceph_mds_client
;
137 * request completion callback
139 typedef void (*ceph_mds_request_callback_t
) (struct ceph_mds_client
*mdsc
,
140 struct ceph_mds_request
*req
);
143 * an in-flight mds request
145 struct ceph_mds_request
{
146 u64 r_tid
; /* transaction id */
148 int r_op
; /* mds op code */
151 /* operation on what? */
152 struct inode
*r_inode
; /* arg1 */
153 struct dentry
*r_dentry
; /* arg1 */
154 struct dentry
*r_old_dentry
; /* arg2: rename from or link from */
155 char *r_path1
, *r_path2
;
156 struct ceph_vino r_ino1
, r_ino2
;
158 struct inode
*r_locked_dir
; /* dir (if any) i_mutex locked by vfs */
159 struct inode
*r_target_inode
; /* resulting inode */
161 union ceph_mds_request_args r_args
;
162 int r_fmode
; /* file mode, if expecting cap */
164 /* for choosing which mds to send this request to */
166 u32 r_direct_hash
; /* choose dir frag based on this dentry hash */
167 bool r_direct_is_hash
; /* true if r_direct_hash is valid */
169 /* data payload is used for xattr ops */
170 struct page
**r_pages
;
174 /* what caps shall we drop? */
175 int r_inode_drop
, r_inode_unless
;
176 int r_dentry_drop
, r_dentry_unless
;
177 int r_old_dentry_drop
, r_old_dentry_unless
;
178 struct inode
*r_old_inode
;
179 int r_old_inode_drop
, r_old_inode_unless
;
181 struct ceph_msg
*r_request
; /* original request */
182 struct ceph_msg
*r_reply
;
183 struct ceph_mds_reply_info_parsed r_reply_info
;
186 unsigned long r_timeout
; /* optional. jiffies */
187 unsigned long r_started
; /* start time to measure timeout against */
188 unsigned long r_request_started
; /* start time for mds request only,
189 used to measure lease durations */
191 /* link unsafe requests to parent directory, for fsync */
192 struct inode
*r_unsafe_dir
;
193 struct list_head r_unsafe_dir_item
;
195 struct ceph_mds_session
*r_session
;
197 int r_attempts
; /* resend attempts */
198 int r_num_fwd
; /* number of forward attempts */
200 int r_resend_mds
; /* mds to resend to next, if any*/
203 struct list_head r_wait
;
204 struct completion r_completion
;
205 struct completion r_safe_completion
;
206 ceph_mds_request_callback_t r_callback
;
207 struct list_head r_unsafe_item
; /* per-session unsafe list item */
208 bool r_got_unsafe
, r_got_safe
;
210 bool r_did_prepopulate
;
211 u32 r_readdir_offset
;
213 struct ceph_cap_reservation r_caps_reservation
;
220 struct ceph_mds_client
{
221 struct ceph_client
*client
;
222 struct mutex mutex
; /* all nested structures */
224 struct ceph_mdsmap
*mdsmap
;
225 struct completion safe_umount_waiters
, session_close_waiters
;
226 struct list_head waiting_for_map
;
228 struct ceph_mds_session
**sessions
; /* NULL for mds if no session */
229 int max_sessions
; /* len of s_mds_sessions */
230 int stopping
; /* true if shutting down */
233 * snap_rwsem will cover cap linkage into snaprealms, and
234 * realm snap contexts. (later, we can do per-realm snap
235 * contexts locks..) the empty list contains realms with no
236 * references (implying they contain no inodes with caps) that
237 * should be destroyed.
239 struct rw_semaphore snap_rwsem
;
240 struct radix_tree_root snap_realms
;
241 struct list_head snap_empty
;
242 spinlock_t snap_empty_lock
; /* protect snap_empty */
244 u64 last_tid
; /* most recent mds request */
245 struct radix_tree_root request_tree
; /* pending mds requests */
246 struct delayed_work delayed_work
; /* delayed work */
247 unsigned long last_renew_caps
; /* last time we renewed our caps */
248 struct list_head cap_delay_list
; /* caps with delayed release */
249 spinlock_t cap_delay_lock
; /* protects cap_delay_list */
250 struct list_head snap_flush_list
; /* cap_snaps ready to flush */
251 spinlock_t snap_flush_lock
;
254 struct list_head cap_dirty
; /* inodes with dirty caps */
255 int num_cap_flushing
; /* # caps we are flushing */
256 spinlock_t cap_dirty_lock
; /* protects above items */
257 wait_queue_head_t cap_flushing_wq
;
259 #ifdef CONFIG_DEBUG_FS
260 struct dentry
*debugfs_file
;
263 spinlock_t dentry_lru_lock
;
264 struct list_head dentry_lru
;
268 extern const char *ceph_mds_op_name(int op
);
270 extern struct ceph_mds_session
*
271 __ceph_lookup_mds_session(struct ceph_mds_client
*, int mds
);
273 static inline struct ceph_mds_session
*
274 ceph_get_mds_session(struct ceph_mds_session
*s
)
276 atomic_inc(&s
->s_ref
);
280 extern void ceph_put_mds_session(struct ceph_mds_session
*s
);
282 extern int ceph_send_msg_mds(struct ceph_mds_client
*mdsc
,
283 struct ceph_msg
*msg
, int mds
);
285 extern int ceph_mdsc_init(struct ceph_mds_client
*mdsc
,
286 struct ceph_client
*client
);
287 extern void ceph_mdsc_close_sessions(struct ceph_mds_client
*mdsc
);
288 extern void ceph_mdsc_stop(struct ceph_mds_client
*mdsc
);
290 extern void ceph_mdsc_sync(struct ceph_mds_client
*mdsc
);
292 extern void ceph_mdsc_lease_release(struct ceph_mds_client
*mdsc
,
294 struct dentry
*dn
, int mask
);
296 extern struct ceph_mds_request
*
297 ceph_mdsc_create_request(struct ceph_mds_client
*mdsc
, int op
, int mode
);
298 extern void ceph_mdsc_submit_request(struct ceph_mds_client
*mdsc
,
299 struct ceph_mds_request
*req
);
300 extern int ceph_mdsc_do_request(struct ceph_mds_client
*mdsc
,
302 struct ceph_mds_request
*req
);
303 static inline void ceph_mdsc_get_request(struct ceph_mds_request
*req
)
305 atomic_inc(&req
->r_ref
);
307 extern void ceph_mdsc_put_request(struct ceph_mds_request
*req
);
309 extern void ceph_mdsc_pre_umount(struct ceph_mds_client
*mdsc
);
311 extern char *ceph_mdsc_build_path(struct dentry
*dentry
, int *plen
, u64
*base
,
314 extern void __ceph_mdsc_drop_dentry_lease(struct dentry
*dentry
);
315 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session
*session
,
317 struct dentry
*dentry
, char action
,
320 extern void ceph_mdsc_handle_map(struct ceph_mds_client
*mdsc
,
321 struct ceph_msg
*msg
);