1 #ifndef _FS_CEPH_MDS_CLIENT_H 2 #define _FS_CEPH_MDS_CLIENT_H 3 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> 10 11 #include <linux/ceph/types.h> 12 #include <linux/ceph/messenger.h> 13 #include <linux/ceph/mdsmap.h> 14 #include <linux/ceph/auth.h> 15 16 /* 17 * Some lock dependencies: 18 * 19 * session->s_mutex 20 * mdsc->mutex 21 * 22 * mdsc->snap_rwsem 23 * 24 * ci->i_ceph_lock 25 * mdsc->snap_flush_lock 26 * mdsc->cap_delay_lock 27 * 28 */ 29 30 struct ceph_fs_client; 31 struct ceph_cap; 32 33 /* 34 * parsed info about a single inode. pointers are into the encoded 35 * on-wire structures within the mds reply message payload. 36 */ 37 struct ceph_mds_reply_info_in { 38 struct ceph_mds_reply_inode *in; 39 struct ceph_dir_layout dir_layout; 40 u32 symlink_len; 41 char *symlink; 42 u32 xattr_len; 43 char *xattr_data; 44 u64 inline_version; 45 u32 inline_len; 46 char *inline_data; 47 }; 48 49 /* 50 * parsed info about an mds reply, including information about 51 * either: 1) the target inode and/or its parent directory and dentry, 52 * and directory contents (for readdir results), or 53 * 2) the file range lock info (for fcntl F_GETLK results). 54 */ 55 struct ceph_mds_reply_info_parsed { 56 struct ceph_mds_reply_head *head; 57 58 /* trace */ 59 struct ceph_mds_reply_info_in diri, targeti; 60 struct ceph_mds_reply_dirfrag *dirfrag; 61 char *dname; 62 u32 dname_len; 63 struct ceph_mds_reply_lease *dlease; 64 65 /* extra */ 66 union { 67 /* for fcntl F_GETLK results */ 68 struct ceph_filelock *filelock_reply; 69 70 /* for readdir results */ 71 struct { 72 struct ceph_mds_reply_dirfrag *dir_dir; 73 size_t dir_buf_size; 74 int dir_nr; 75 char **dir_dname; 76 u32 *dir_dname_len; 77 struct ceph_mds_reply_lease **dir_dlease; 78 struct ceph_mds_reply_info_in *dir_in; 79 u8 dir_complete, dir_end; 80 }; 81 82 /* for create results */ 83 struct { 84 bool has_create_ino; 85 u64 ino; 86 }; 87 }; 88 89 /* encoded blob describing snapshot contexts for certain 90 operations (e.g., open) */ 91 void *snapblob; 92 int snapblob_len; 93 }; 94 95 96 /* 97 * cap releases are batched and sent to the MDS en masse. 98 */ 99 #define CEPH_CAPS_PER_RELEASE ((PAGE_CACHE_SIZE - \ 100 sizeof(struct ceph_mds_cap_release)) / \ 101 sizeof(struct ceph_mds_cap_item)) 102 103 104 /* 105 * state associated with each MDS<->client session 106 */ 107 enum { 108 CEPH_MDS_SESSION_NEW = 1, 109 CEPH_MDS_SESSION_OPENING = 2, 110 CEPH_MDS_SESSION_OPEN = 3, 111 CEPH_MDS_SESSION_HUNG = 4, 112 CEPH_MDS_SESSION_CLOSING = 5, 113 CEPH_MDS_SESSION_RESTARTING = 6, 114 CEPH_MDS_SESSION_RECONNECTING = 7, 115 }; 116 117 struct ceph_mds_session { 118 struct ceph_mds_client *s_mdsc; 119 int s_mds; 120 int s_state; 121 unsigned long s_ttl; /* time until mds kills us */ 122 u64 s_seq; /* incoming msg seq # */ 123 struct mutex s_mutex; /* serialize session messages */ 124 125 struct ceph_connection s_con; 126 127 struct ceph_auth_handshake s_auth; 128 129 /* protected by s_gen_ttl_lock */ 130 spinlock_t s_gen_ttl_lock; 131 u32 s_cap_gen; /* inc each time we get mds stale msg */ 132 unsigned long s_cap_ttl; /* when session caps expire */ 133 134 /* protected by s_cap_lock */ 135 spinlock_t s_cap_lock; 136 struct list_head s_caps; /* all caps issued by this session */ 137 int s_nr_caps, s_trim_caps; 138 int s_num_cap_releases; 139 int s_cap_reconnect; 140 int s_readonly; 141 struct list_head s_cap_releases; /* waiting cap_release messages */ 142 struct ceph_cap *s_cap_iterator; 143 144 /* protected by mutex */ 145 struct list_head s_cap_flushing; /* inodes w/ flushing caps */ 146 struct list_head s_cap_snaps_flushing; 147 unsigned long s_renew_requested; /* last time we sent a renew req */ 148 u64 s_renew_seq; 149 150 atomic_t s_ref; 151 struct list_head s_waiting; /* waiting requests */ 152 struct list_head s_unsafe; /* unsafe requests */ 153 }; 154 155 /* 156 * modes of choosing which MDS to send a request to 157 */ 158 enum { 159 USE_ANY_MDS, 160 USE_RANDOM_MDS, 161 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */ 162 }; 163 164 struct ceph_mds_request; 165 struct ceph_mds_client; 166 167 /* 168 * request completion callback 169 */ 170 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc, 171 struct ceph_mds_request *req); 172 /* 173 * wait for request completion callback 174 */ 175 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc, 176 struct ceph_mds_request *req); 177 178 /* 179 * an in-flight mds request 180 */ 181 struct ceph_mds_request { 182 u64 r_tid; /* transaction id */ 183 struct rb_node r_node; 184 struct ceph_mds_client *r_mdsc; 185 186 int r_op; /* mds op code */ 187 188 /* operation on what? */ 189 struct inode *r_inode; /* arg1 */ 190 struct dentry *r_dentry; /* arg1 */ 191 struct dentry *r_old_dentry; /* arg2: rename from or link from */ 192 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */ 193 char *r_path1, *r_path2; 194 struct ceph_vino r_ino1, r_ino2; 195 196 struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */ 197 struct inode *r_target_inode; /* resulting inode */ 198 199 struct mutex r_fill_mutex; 200 201 union ceph_mds_request_args r_args; 202 int r_fmode; /* file mode, if expecting cap */ 203 kuid_t r_uid; 204 kgid_t r_gid; 205 struct timespec r_stamp; 206 207 /* for choosing which mds to send this request to */ 208 int r_direct_mode; 209 u32 r_direct_hash; /* choose dir frag based on this dentry hash */ 210 bool r_direct_is_hash; /* true if r_direct_hash is valid */ 211 212 /* data payload is used for xattr ops */ 213 struct ceph_pagelist *r_pagelist; 214 215 /* what caps shall we drop? */ 216 int r_inode_drop, r_inode_unless; 217 int r_dentry_drop, r_dentry_unless; 218 int r_old_dentry_drop, r_old_dentry_unless; 219 struct inode *r_old_inode; 220 int r_old_inode_drop, r_old_inode_unless; 221 222 struct ceph_msg *r_request; /* original request */ 223 int r_request_release_offset; 224 struct ceph_msg *r_reply; 225 struct ceph_mds_reply_info_parsed r_reply_info; 226 struct page *r_locked_page; 227 int r_err; 228 bool r_aborted; 229 230 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */ 231 unsigned long r_started; /* start time to measure timeout against */ 232 unsigned long r_request_started; /* start time for mds request only, 233 used to measure lease durations */ 234 235 /* link unsafe requests to parent directory, for fsync */ 236 struct inode *r_unsafe_dir; 237 struct list_head r_unsafe_dir_item; 238 239 /* unsafe requests that modify the target inode */ 240 struct list_head r_unsafe_target_item; 241 242 struct ceph_mds_session *r_session; 243 244 int r_attempts; /* resend attempts */ 245 int r_num_fwd; /* number of forward attempts */ 246 int r_resend_mds; /* mds to resend to next, if any*/ 247 u32 r_sent_on_mseq; /* cap mseq request was sent at*/ 248 249 struct kref r_kref; 250 struct list_head r_wait; 251 struct completion r_completion; 252 struct completion r_safe_completion; 253 ceph_mds_request_callback_t r_callback; 254 ceph_mds_request_wait_callback_t r_wait_for_completion; 255 struct list_head r_unsafe_item; /* per-session unsafe list item */ 256 bool r_got_unsafe, r_got_safe, r_got_result; 257 258 bool r_did_prepopulate; 259 long long r_dir_release_cnt; 260 long long r_dir_ordered_cnt; 261 int r_readdir_cache_idx; 262 u32 r_readdir_offset; 263 264 struct ceph_cap_reservation r_caps_reservation; 265 int r_num_caps; 266 }; 267 268 struct ceph_pool_perm { 269 struct rb_node node; 270 u32 pool; 271 int perm; 272 }; 273 274 /* 275 * mds client state 276 */ 277 struct ceph_mds_client { 278 struct ceph_fs_client *fsc; 279 struct mutex mutex; /* all nested structures */ 280 281 struct ceph_mdsmap *mdsmap; 282 struct completion safe_umount_waiters; 283 wait_queue_head_t session_close_wq; 284 struct list_head waiting_for_map; 285 286 struct ceph_mds_session **sessions; /* NULL for mds if no session */ 287 atomic_t num_sessions; 288 int max_sessions; /* len of s_mds_sessions */ 289 int stopping; /* true if shutting down */ 290 291 /* 292 * snap_rwsem will cover cap linkage into snaprealms, and 293 * realm snap contexts. (later, we can do per-realm snap 294 * contexts locks..) the empty list contains realms with no 295 * references (implying they contain no inodes with caps) that 296 * should be destroyed. 297 */ 298 u64 last_snap_seq; 299 struct rw_semaphore snap_rwsem; 300 struct rb_root snap_realms; 301 struct list_head snap_empty; 302 spinlock_t snap_empty_lock; /* protect snap_empty */ 303 304 u64 last_tid; /* most recent mds request */ 305 u64 oldest_tid; /* oldest incomplete mds request, 306 excluding setfilelock requests */ 307 struct rb_root request_tree; /* pending mds requests */ 308 struct delayed_work delayed_work; /* delayed work */ 309 unsigned long last_renew_caps; /* last time we renewed our caps */ 310 struct list_head cap_delay_list; /* caps with delayed release */ 311 spinlock_t cap_delay_lock; /* protects cap_delay_list */ 312 struct list_head snap_flush_list; /* cap_snaps ready to flush */ 313 spinlock_t snap_flush_lock; 314 315 u64 last_cap_flush_tid; 316 struct rb_root cap_flush_tree; 317 struct list_head cap_dirty; /* inodes with dirty caps */ 318 struct list_head cap_dirty_migrating; /* ...that are migration... */ 319 int num_cap_flushing; /* # caps we are flushing */ 320 spinlock_t cap_dirty_lock; /* protects above items */ 321 wait_queue_head_t cap_flushing_wq; 322 323 /* 324 * Cap reservations 325 * 326 * Maintain a global pool of preallocated struct ceph_caps, referenced 327 * by struct ceph_caps_reservations. This ensures that we preallocate 328 * memory needed to successfully process an MDS response. (If an MDS 329 * sends us cap information and we fail to process it, we will have 330 * problems due to the client and MDS being out of sync.) 331 * 332 * Reservations are 'owned' by a ceph_cap_reservation context. 333 */ 334 spinlock_t caps_list_lock; 335 struct list_head caps_list; /* unused (reserved or 336 unreserved) */ 337 int caps_total_count; /* total caps allocated */ 338 int caps_use_count; /* in use */ 339 int caps_reserve_count; /* unused, reserved */ 340 int caps_avail_count; /* unused, unreserved */ 341 int caps_min_count; /* keep at least this many 342 (unreserved) */ 343 spinlock_t dentry_lru_lock; 344 struct list_head dentry_lru; 345 int num_dentry; 346 347 struct rw_semaphore pool_perm_rwsem; 348 struct rb_root pool_perm_tree; 349 }; 350 351 extern const char *ceph_mds_op_name(int op); 352 353 extern struct ceph_mds_session * 354 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds); 355 356 static inline struct ceph_mds_session * 357 ceph_get_mds_session(struct ceph_mds_session *s) 358 { 359 atomic_inc(&s->s_ref); 360 return s; 361 } 362 363 extern const char *ceph_session_state_name(int s); 364 365 extern void ceph_put_mds_session(struct ceph_mds_session *s); 366 367 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc, 368 struct ceph_msg *msg, int mds); 369 370 extern int ceph_mdsc_init(struct ceph_fs_client *fsc); 371 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc); 372 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc); 373 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc); 374 375 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc); 376 377 extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, 378 struct inode *inode, 379 struct dentry *dn); 380 381 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req); 382 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, 383 struct inode *dir); 384 extern struct ceph_mds_request * 385 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode); 386 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc, 387 struct ceph_mds_request *req); 388 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc, 389 struct inode *dir, 390 struct ceph_mds_request *req); 391 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req) 392 { 393 kref_get(&req->r_kref); 394 } 395 extern void ceph_mdsc_release_request(struct kref *kref); 396 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req) 397 { 398 kref_put(&req->r_kref, ceph_mdsc_release_request); 399 } 400 401 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc, 402 struct ceph_mds_session *session); 403 404 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc); 405 406 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base, 407 int stop_on_nosnap); 408 409 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry); 410 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session, 411 struct inode *inode, 412 struct dentry *dentry, char action, 413 u32 seq); 414 415 extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, 416 struct ceph_msg *msg); 417 418 extern struct ceph_mds_session * 419 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target); 420 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, 421 struct ceph_mds_session *session); 422 423 #endif 424