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 struct dentry *debugfs_file;
261 spinlock_t dentry_lru_lock;
262 struct list_head dentry_lru;
266 extern const char *ceph_mds_op_name(int op);
268 extern struct ceph_mds_session *
269 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
271 static inline struct ceph_mds_session *
272 ceph_get_mds_session(struct ceph_mds_session *s)
274 atomic_inc(&s->s_ref);
278 extern void ceph_put_mds_session(struct ceph_mds_session *s);
280 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
281 struct ceph_msg *msg, int mds);
283 extern void ceph_mdsc_init(struct ceph_mds_client *mdsc,
284 struct ceph_client *client);
285 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
286 extern void ceph_mdsc_stop(struct ceph_mds_client *mdsc);
288 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
290 extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc,
292 struct dentry *dn, int mask);
294 extern struct ceph_mds_request *
295 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
296 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
297 struct ceph_mds_request *req);
298 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
300 struct ceph_mds_request *req);
301 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
303 atomic_inc(&req->r_ref);
305 extern void ceph_mdsc_put_request(struct ceph_mds_request *req);
307 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
309 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
312 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
313 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
315 struct dentry *dentry, char action,
318 extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc,
319 struct ceph_msg *msg);