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 u32 pool_ns_len; 48 char *pool_ns_data; 49 }; 50 51 struct ceph_mds_reply_dir_entry { 52 char *name; 53 u32 name_len; 54 struct ceph_mds_reply_lease *lease; 55 struct ceph_mds_reply_info_in inode; 56 loff_t offset; 57 }; 58 59 /* 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). 64 */ 65 struct ceph_mds_reply_info_parsed { 66 struct ceph_mds_reply_head *head; 67 68 /* trace */ 69 struct ceph_mds_reply_info_in diri, targeti; 70 struct ceph_mds_reply_dirfrag *dirfrag; 71 char *dname; 72 u32 dname_len; 73 struct ceph_mds_reply_lease *dlease; 74 75 /* extra */ 76 union { 77 /* for fcntl F_GETLK results */ 78 struct ceph_filelock *filelock_reply; 79 80 /* for readdir results */ 81 struct { 82 struct ceph_mds_reply_dirfrag *dir_dir; 83 size_t dir_buf_size; 84 int dir_nr; 85 bool dir_complete; 86 bool dir_end; 87 bool hash_order; 88 struct ceph_mds_reply_dir_entry *dir_entries; 89 }; 90 91 /* for create results */ 92 struct { 93 bool has_create_ino; 94 u64 ino; 95 }; 96 }; 97 98 /* encoded blob describing snapshot contexts for certain 99 operations (e.g., open) */ 100 void *snapblob; 101 int snapblob_len; 102 }; 103 104 105 /* 106 * cap releases are batched and sent to the MDS en masse. 107 */ 108 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - \ 109 sizeof(struct ceph_mds_cap_release)) / \ 110 sizeof(struct ceph_mds_cap_item)) 111 112 113 /* 114 * state associated with each MDS<->client session 115 */ 116 enum { 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, 124 CEPH_MDS_SESSION_REJECTED = 8, 125 }; 126 127 struct ceph_mds_session { 128 struct ceph_mds_client *s_mdsc; 129 int s_mds; 130 int s_state; 131 unsigned long s_ttl; /* time until mds kills us */ 132 u64 s_seq; /* incoming msg seq # */ 133 struct mutex s_mutex; /* serialize session messages */ 134 135 struct ceph_connection s_con; 136 137 struct ceph_auth_handshake s_auth; 138 139 /* protected by s_gen_ttl_lock */ 140 spinlock_t s_gen_ttl_lock; 141 u32 s_cap_gen; /* inc each time we get mds stale msg */ 142 unsigned long s_cap_ttl; /* when session caps expire */ 143 144 /* protected by s_cap_lock */ 145 spinlock_t s_cap_lock; 146 struct list_head s_caps; /* all caps issued by this session */ 147 int s_nr_caps, s_trim_caps; 148 int s_num_cap_releases; 149 int s_cap_reconnect; 150 int s_readonly; 151 struct list_head s_cap_releases; /* waiting cap_release messages */ 152 struct ceph_cap *s_cap_iterator; 153 154 /* protected by mutex */ 155 struct list_head s_cap_flushing; /* inodes w/ flushing caps */ 156 unsigned long s_renew_requested; /* last time we sent a renew req */ 157 u64 s_renew_seq; 158 159 atomic_t s_ref; 160 struct list_head s_waiting; /* waiting requests */ 161 struct list_head s_unsafe; /* unsafe requests */ 162 }; 163 164 /* 165 * modes of choosing which MDS to send a request to 166 */ 167 enum { 168 USE_ANY_MDS, 169 USE_RANDOM_MDS, 170 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */ 171 }; 172 173 struct ceph_mds_request; 174 struct ceph_mds_client; 175 176 /* 177 * request completion callback 178 */ 179 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc, 180 struct ceph_mds_request *req); 181 /* 182 * wait for request completion callback 183 */ 184 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc, 185 struct ceph_mds_request *req); 186 187 /* 188 * an in-flight mds request 189 */ 190 struct ceph_mds_request { 191 u64 r_tid; /* transaction id */ 192 struct rb_node r_node; 193 struct ceph_mds_client *r_mdsc; 194 195 int r_op; /* mds op code */ 196 197 /* operation on what? */ 198 struct inode *r_inode; /* arg1 */ 199 struct dentry *r_dentry; /* arg1 */ 200 struct dentry *r_old_dentry; /* arg2: rename from or link from */ 201 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */ 202 char *r_path1, *r_path2; 203 struct ceph_vino r_ino1, r_ino2; 204 205 struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */ 206 struct inode *r_target_inode; /* resulting inode */ 207 208 struct mutex r_fill_mutex; 209 210 union ceph_mds_request_args r_args; 211 int r_fmode; /* file mode, if expecting cap */ 212 kuid_t r_uid; 213 kgid_t r_gid; 214 struct timespec r_stamp; 215 216 /* for choosing which mds to send this request to */ 217 int r_direct_mode; 218 u32 r_direct_hash; /* choose dir frag based on this dentry hash */ 219 bool r_direct_is_hash; /* true if r_direct_hash is valid */ 220 221 /* data payload is used for xattr ops */ 222 struct ceph_pagelist *r_pagelist; 223 224 /* what caps shall we drop? */ 225 int r_inode_drop, r_inode_unless; 226 int r_dentry_drop, r_dentry_unless; 227 int r_old_dentry_drop, r_old_dentry_unless; 228 struct inode *r_old_inode; 229 int r_old_inode_drop, r_old_inode_unless; 230 231 struct ceph_msg *r_request; /* original request */ 232 int r_request_release_offset; 233 struct ceph_msg *r_reply; 234 struct ceph_mds_reply_info_parsed r_reply_info; 235 struct page *r_locked_page; 236 int r_err; 237 bool r_aborted; 238 239 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */ 240 unsigned long r_started; /* start time to measure timeout against */ 241 unsigned long r_request_started; /* start time for mds request only, 242 used to measure lease durations */ 243 244 /* link unsafe requests to parent directory, for fsync */ 245 struct inode *r_unsafe_dir; 246 struct list_head r_unsafe_dir_item; 247 248 /* unsafe requests that modify the target inode */ 249 struct list_head r_unsafe_target_item; 250 251 struct ceph_mds_session *r_session; 252 253 int r_attempts; /* resend attempts */ 254 int r_num_fwd; /* number of forward attempts */ 255 int r_resend_mds; /* mds to resend to next, if any*/ 256 u32 r_sent_on_mseq; /* cap mseq request was sent at*/ 257 258 struct kref r_kref; 259 struct list_head r_wait; 260 struct completion r_completion; 261 struct completion r_safe_completion; 262 ceph_mds_request_callback_t r_callback; 263 ceph_mds_request_wait_callback_t r_wait_for_completion; 264 struct list_head r_unsafe_item; /* per-session unsafe list item */ 265 bool r_got_unsafe, r_got_safe, r_got_result; 266 267 bool r_did_prepopulate; 268 long long r_dir_release_cnt; 269 long long r_dir_ordered_cnt; 270 int r_readdir_cache_idx; 271 u32 r_readdir_offset; 272 273 struct ceph_cap_reservation r_caps_reservation; 274 int r_num_caps; 275 }; 276 277 struct ceph_pool_perm { 278 struct rb_node node; 279 int perm; 280 s64 pool; 281 size_t pool_ns_len; 282 char pool_ns[]; 283 }; 284 285 /* 286 * mds client state 287 */ 288 struct ceph_mds_client { 289 struct ceph_fs_client *fsc; 290 struct mutex mutex; /* all nested structures */ 291 292 struct ceph_mdsmap *mdsmap; 293 struct completion safe_umount_waiters; 294 wait_queue_head_t session_close_wq; 295 struct list_head waiting_for_map; 296 int mdsmap_err; 297 298 struct ceph_mds_session **sessions; /* NULL for mds if no session */ 299 atomic_t num_sessions; 300 int max_sessions; /* len of s_mds_sessions */ 301 int stopping; /* true if shutting down */ 302 303 /* 304 * snap_rwsem will cover cap linkage into snaprealms, and 305 * realm snap contexts. (later, we can do per-realm snap 306 * contexts locks..) the empty list contains realms with no 307 * references (implying they contain no inodes with caps) that 308 * should be destroyed. 309 */ 310 u64 last_snap_seq; 311 struct rw_semaphore snap_rwsem; 312 struct rb_root snap_realms; 313 struct list_head snap_empty; 314 spinlock_t snap_empty_lock; /* protect snap_empty */ 315 316 u64 last_tid; /* most recent mds request */ 317 u64 oldest_tid; /* oldest incomplete mds request, 318 excluding setfilelock requests */ 319 struct rb_root request_tree; /* pending mds requests */ 320 struct delayed_work delayed_work; /* delayed work */ 321 unsigned long last_renew_caps; /* last time we renewed our caps */ 322 struct list_head cap_delay_list; /* caps with delayed release */ 323 spinlock_t cap_delay_lock; /* protects cap_delay_list */ 324 struct list_head snap_flush_list; /* cap_snaps ready to flush */ 325 spinlock_t snap_flush_lock; 326 327 u64 last_cap_flush_tid; 328 struct list_head cap_flush_list; 329 struct list_head cap_dirty; /* inodes with dirty caps */ 330 struct list_head cap_dirty_migrating; /* ...that are migration... */ 331 int num_cap_flushing; /* # caps we are flushing */ 332 spinlock_t cap_dirty_lock; /* protects above items */ 333 wait_queue_head_t cap_flushing_wq; 334 335 /* 336 * Cap reservations 337 * 338 * Maintain a global pool of preallocated struct ceph_caps, referenced 339 * by struct ceph_caps_reservations. This ensures that we preallocate 340 * memory needed to successfully process an MDS response. (If an MDS 341 * sends us cap information and we fail to process it, we will have 342 * problems due to the client and MDS being out of sync.) 343 * 344 * Reservations are 'owned' by a ceph_cap_reservation context. 345 */ 346 spinlock_t caps_list_lock; 347 struct list_head caps_list; /* unused (reserved or 348 unreserved) */ 349 int caps_total_count; /* total caps allocated */ 350 int caps_use_count; /* in use */ 351 int caps_reserve_count; /* unused, reserved */ 352 int caps_avail_count; /* unused, unreserved */ 353 int caps_min_count; /* keep at least this many 354 (unreserved) */ 355 spinlock_t dentry_lru_lock; 356 struct list_head dentry_lru; 357 int num_dentry; 358 359 struct rw_semaphore pool_perm_rwsem; 360 struct rb_root pool_perm_tree; 361 }; 362 363 extern const char *ceph_mds_op_name(int op); 364 365 extern struct ceph_mds_session * 366 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds); 367 368 static inline struct ceph_mds_session * 369 ceph_get_mds_session(struct ceph_mds_session *s) 370 { 371 atomic_inc(&s->s_ref); 372 return s; 373 } 374 375 extern const char *ceph_session_state_name(int s); 376 377 extern void ceph_put_mds_session(struct ceph_mds_session *s); 378 379 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc, 380 struct ceph_msg *msg, int mds); 381 382 extern int ceph_mdsc_init(struct ceph_fs_client *fsc); 383 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc); 384 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc); 385 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc); 386 387 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc); 388 389 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req); 390 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, 391 struct inode *dir); 392 extern struct ceph_mds_request * 393 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode); 394 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc, 395 struct ceph_mds_request *req); 396 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc, 397 struct inode *dir, 398 struct ceph_mds_request *req); 399 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req) 400 { 401 kref_get(&req->r_kref); 402 } 403 extern void ceph_mdsc_release_request(struct kref *kref); 404 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req) 405 { 406 kref_put(&req->r_kref, ceph_mdsc_release_request); 407 } 408 409 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc, 410 struct ceph_mds_session *session); 411 412 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc); 413 414 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base, 415 int stop_on_nosnap); 416 417 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry); 418 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session, 419 struct inode *inode, 420 struct dentry *dentry, char action, 421 u32 seq); 422 423 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc, 424 struct ceph_msg *msg); 425 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, 426 struct ceph_msg *msg); 427 428 extern struct ceph_mds_session * 429 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target); 430 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, 431 struct ceph_mds_session *session); 432 433 #endif 434