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 #include <linux/refcount.h> 11 12 #include <linux/ceph/types.h> 13 #include <linux/ceph/messenger.h> 14 #include <linux/ceph/mdsmap.h> 15 #include <linux/ceph/auth.h> 16 17 /* 18 * Some lock dependencies: 19 * 20 * session->s_mutex 21 * mdsc->mutex 22 * 23 * mdsc->snap_rwsem 24 * 25 * ci->i_ceph_lock 26 * mdsc->snap_flush_lock 27 * mdsc->cap_delay_lock 28 * 29 */ 30 31 struct ceph_fs_client; 32 struct ceph_cap; 33 34 /* 35 * parsed info about a single inode. pointers are into the encoded 36 * on-wire structures within the mds reply message payload. 37 */ 38 struct ceph_mds_reply_info_in { 39 struct ceph_mds_reply_inode *in; 40 struct ceph_dir_layout dir_layout; 41 u32 symlink_len; 42 char *symlink; 43 u32 xattr_len; 44 char *xattr_data; 45 u64 inline_version; 46 u32 inline_len; 47 char *inline_data; 48 u32 pool_ns_len; 49 char *pool_ns_data; 50 }; 51 52 struct ceph_mds_reply_dir_entry { 53 char *name; 54 u32 name_len; 55 struct ceph_mds_reply_lease *lease; 56 struct ceph_mds_reply_info_in inode; 57 loff_t offset; 58 }; 59 60 /* 61 * parsed info about an mds reply, including information about 62 * either: 1) the target inode and/or its parent directory and dentry, 63 * and directory contents (for readdir results), or 64 * 2) the file range lock info (for fcntl F_GETLK results). 65 */ 66 struct ceph_mds_reply_info_parsed { 67 struct ceph_mds_reply_head *head; 68 69 /* trace */ 70 struct ceph_mds_reply_info_in diri, targeti; 71 struct ceph_mds_reply_dirfrag *dirfrag; 72 char *dname; 73 u32 dname_len; 74 struct ceph_mds_reply_lease *dlease; 75 76 /* extra */ 77 union { 78 /* for fcntl F_GETLK results */ 79 struct ceph_filelock *filelock_reply; 80 81 /* for readdir results */ 82 struct { 83 struct ceph_mds_reply_dirfrag *dir_dir; 84 size_t dir_buf_size; 85 int dir_nr; 86 bool dir_end; 87 bool dir_complete; 88 bool hash_order; 89 bool offset_hash; 90 struct ceph_mds_reply_dir_entry *dir_entries; 91 }; 92 93 /* for create results */ 94 struct { 95 bool has_create_ino; 96 u64 ino; 97 }; 98 }; 99 100 /* encoded blob describing snapshot contexts for certain 101 operations (e.g., open) */ 102 void *snapblob; 103 int snapblob_len; 104 }; 105 106 107 /* 108 * cap releases are batched and sent to the MDS en masse. 109 * 110 * Account for per-message overhead of mds_cap_release header 111 * and __le32 for osd epoch barrier trailing field. 112 */ 113 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) - \ 114 sizeof(struct ceph_mds_cap_release)) / \ 115 sizeof(struct ceph_mds_cap_item)) 116 117 118 /* 119 * state associated with each MDS<->client session 120 */ 121 enum { 122 CEPH_MDS_SESSION_NEW = 1, 123 CEPH_MDS_SESSION_OPENING = 2, 124 CEPH_MDS_SESSION_OPEN = 3, 125 CEPH_MDS_SESSION_HUNG = 4, 126 CEPH_MDS_SESSION_CLOSING = 5, 127 CEPH_MDS_SESSION_RESTARTING = 6, 128 CEPH_MDS_SESSION_RECONNECTING = 7, 129 CEPH_MDS_SESSION_REJECTED = 8, 130 }; 131 132 struct ceph_mds_session { 133 struct ceph_mds_client *s_mdsc; 134 int s_mds; 135 int s_state; 136 unsigned long s_ttl; /* time until mds kills us */ 137 u64 s_seq; /* incoming msg seq # */ 138 struct mutex s_mutex; /* serialize session messages */ 139 140 struct ceph_connection s_con; 141 142 struct ceph_auth_handshake s_auth; 143 144 /* protected by s_gen_ttl_lock */ 145 spinlock_t s_gen_ttl_lock; 146 u32 s_cap_gen; /* inc each time we get mds stale msg */ 147 unsigned long s_cap_ttl; /* when session caps expire */ 148 149 /* protected by s_cap_lock */ 150 spinlock_t s_cap_lock; 151 struct list_head s_caps; /* all caps issued by this session */ 152 int s_nr_caps, s_trim_caps; 153 int s_num_cap_releases; 154 int s_cap_reconnect; 155 int s_readonly; 156 struct list_head s_cap_releases; /* waiting cap_release messages */ 157 struct ceph_cap *s_cap_iterator; 158 159 /* protected by mutex */ 160 struct list_head s_cap_flushing; /* inodes w/ flushing caps */ 161 unsigned long s_renew_requested; /* last time we sent a renew req */ 162 u64 s_renew_seq; 163 164 refcount_t s_ref; 165 struct list_head s_waiting; /* waiting requests */ 166 struct list_head s_unsafe; /* unsafe requests */ 167 }; 168 169 /* 170 * modes of choosing which MDS to send a request to 171 */ 172 enum { 173 USE_ANY_MDS, 174 USE_RANDOM_MDS, 175 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */ 176 }; 177 178 struct ceph_mds_request; 179 struct ceph_mds_client; 180 181 /* 182 * request completion callback 183 */ 184 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc, 185 struct ceph_mds_request *req); 186 /* 187 * wait for request completion callback 188 */ 189 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc, 190 struct ceph_mds_request *req); 191 192 /* 193 * an in-flight mds request 194 */ 195 struct ceph_mds_request { 196 u64 r_tid; /* transaction id */ 197 struct rb_node r_node; 198 struct ceph_mds_client *r_mdsc; 199 200 int r_op; /* mds op code */ 201 202 /* operation on what? */ 203 struct inode *r_inode; /* arg1 */ 204 struct dentry *r_dentry; /* arg1 */ 205 struct dentry *r_old_dentry; /* arg2: rename from or link from */ 206 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */ 207 char *r_path1, *r_path2; 208 struct ceph_vino r_ino1, r_ino2; 209 210 struct inode *r_parent; /* parent dir inode */ 211 struct inode *r_target_inode; /* resulting inode */ 212 213 #define CEPH_MDS_R_DIRECT_IS_HASH (1) /* r_direct_hash is valid */ 214 #define CEPH_MDS_R_ABORTED (2) /* call was aborted */ 215 #define CEPH_MDS_R_GOT_UNSAFE (3) /* got an unsafe reply */ 216 #define CEPH_MDS_R_GOT_SAFE (4) /* got a safe reply */ 217 #define CEPH_MDS_R_GOT_RESULT (5) /* got a result */ 218 #define CEPH_MDS_R_DID_PREPOPULATE (6) /* prepopulated readdir */ 219 #define CEPH_MDS_R_PARENT_LOCKED (7) /* is r_parent->i_rwsem wlocked? */ 220 unsigned long r_req_flags; 221 222 struct mutex r_fill_mutex; 223 224 union ceph_mds_request_args r_args; 225 int r_fmode; /* file mode, if expecting cap */ 226 kuid_t r_uid; 227 kgid_t r_gid; 228 struct timespec r_stamp; 229 230 /* for choosing which mds to send this request to */ 231 int r_direct_mode; 232 u32 r_direct_hash; /* choose dir frag based on this dentry hash */ 233 234 /* data payload is used for xattr ops */ 235 struct ceph_pagelist *r_pagelist; 236 237 /* what caps shall we drop? */ 238 int r_inode_drop, r_inode_unless; 239 int r_dentry_drop, r_dentry_unless; 240 int r_old_dentry_drop, r_old_dentry_unless; 241 struct inode *r_old_inode; 242 int r_old_inode_drop, r_old_inode_unless; 243 244 struct ceph_msg *r_request; /* original request */ 245 int r_request_release_offset; 246 struct ceph_msg *r_reply; 247 struct ceph_mds_reply_info_parsed r_reply_info; 248 struct page *r_locked_page; 249 int r_err; 250 251 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */ 252 unsigned long r_started; /* start time to measure timeout against */ 253 unsigned long r_request_started; /* start time for mds request only, 254 used to measure lease durations */ 255 256 /* link unsafe requests to parent directory, for fsync */ 257 struct inode *r_unsafe_dir; 258 struct list_head r_unsafe_dir_item; 259 260 /* unsafe requests that modify the target inode */ 261 struct list_head r_unsafe_target_item; 262 263 struct ceph_mds_session *r_session; 264 265 int r_attempts; /* resend attempts */ 266 int r_num_fwd; /* number of forward attempts */ 267 int r_resend_mds; /* mds to resend to next, if any*/ 268 u32 r_sent_on_mseq; /* cap mseq request was sent at*/ 269 270 struct kref r_kref; 271 struct list_head r_wait; 272 struct completion r_completion; 273 struct completion r_safe_completion; 274 ceph_mds_request_callback_t r_callback; 275 ceph_mds_request_wait_callback_t r_wait_for_completion; 276 struct list_head r_unsafe_item; /* per-session unsafe list item */ 277 278 long long r_dir_release_cnt; 279 long long r_dir_ordered_cnt; 280 int r_readdir_cache_idx; 281 u32 r_readdir_offset; 282 283 struct ceph_cap_reservation r_caps_reservation; 284 int r_num_caps; 285 }; 286 287 struct ceph_pool_perm { 288 struct rb_node node; 289 int perm; 290 s64 pool; 291 size_t pool_ns_len; 292 char pool_ns[]; 293 }; 294 295 /* 296 * mds client state 297 */ 298 struct ceph_mds_client { 299 struct ceph_fs_client *fsc; 300 struct mutex mutex; /* all nested structures */ 301 302 struct ceph_mdsmap *mdsmap; 303 struct completion safe_umount_waiters; 304 wait_queue_head_t session_close_wq; 305 struct list_head waiting_for_map; 306 int mdsmap_err; 307 308 struct ceph_mds_session **sessions; /* NULL for mds if no session */ 309 atomic_t num_sessions; 310 int max_sessions; /* len of s_mds_sessions */ 311 int stopping; /* true if shutting down */ 312 313 /* 314 * snap_rwsem will cover cap linkage into snaprealms, and 315 * realm snap contexts. (later, we can do per-realm snap 316 * contexts locks..) the empty list contains realms with no 317 * references (implying they contain no inodes with caps) that 318 * should be destroyed. 319 */ 320 u64 last_snap_seq; 321 struct rw_semaphore snap_rwsem; 322 struct rb_root snap_realms; 323 struct list_head snap_empty; 324 spinlock_t snap_empty_lock; /* protect snap_empty */ 325 326 u64 last_tid; /* most recent mds request */ 327 u64 oldest_tid; /* oldest incomplete mds request, 328 excluding setfilelock requests */ 329 struct rb_root request_tree; /* pending mds requests */ 330 struct delayed_work delayed_work; /* delayed work */ 331 unsigned long last_renew_caps; /* last time we renewed our caps */ 332 struct list_head cap_delay_list; /* caps with delayed release */ 333 spinlock_t cap_delay_lock; /* protects cap_delay_list */ 334 struct list_head snap_flush_list; /* cap_snaps ready to flush */ 335 spinlock_t snap_flush_lock; 336 337 u64 last_cap_flush_tid; 338 struct list_head cap_flush_list; 339 struct list_head cap_dirty; /* inodes with dirty caps */ 340 struct list_head cap_dirty_migrating; /* ...that are migration... */ 341 int num_cap_flushing; /* # caps we are flushing */ 342 spinlock_t cap_dirty_lock; /* protects above items */ 343 wait_queue_head_t cap_flushing_wq; 344 345 /* 346 * Cap reservations 347 * 348 * Maintain a global pool of preallocated struct ceph_caps, referenced 349 * by struct ceph_caps_reservations. This ensures that we preallocate 350 * memory needed to successfully process an MDS response. (If an MDS 351 * sends us cap information and we fail to process it, we will have 352 * problems due to the client and MDS being out of sync.) 353 * 354 * Reservations are 'owned' by a ceph_cap_reservation context. 355 */ 356 spinlock_t caps_list_lock; 357 struct list_head caps_list; /* unused (reserved or 358 unreserved) */ 359 int caps_total_count; /* total caps allocated */ 360 int caps_use_count; /* in use */ 361 int caps_reserve_count; /* unused, reserved */ 362 int caps_avail_count; /* unused, unreserved */ 363 int caps_min_count; /* keep at least this many 364 (unreserved) */ 365 spinlock_t dentry_lru_lock; 366 struct list_head dentry_lru; 367 int num_dentry; 368 369 struct rw_semaphore pool_perm_rwsem; 370 struct rb_root pool_perm_tree; 371 }; 372 373 extern const char *ceph_mds_op_name(int op); 374 375 extern struct ceph_mds_session * 376 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds); 377 378 static inline struct ceph_mds_session * 379 ceph_get_mds_session(struct ceph_mds_session *s) 380 { 381 refcount_inc(&s->s_ref); 382 return s; 383 } 384 385 extern const char *ceph_session_state_name(int s); 386 387 extern void ceph_put_mds_session(struct ceph_mds_session *s); 388 389 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc, 390 struct ceph_msg *msg, int mds); 391 392 extern int ceph_mdsc_init(struct ceph_fs_client *fsc); 393 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc); 394 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc); 395 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc); 396 397 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc); 398 399 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req); 400 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, 401 struct inode *dir); 402 extern struct ceph_mds_request * 403 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode); 404 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc, 405 struct ceph_mds_request *req); 406 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc, 407 struct inode *dir, 408 struct ceph_mds_request *req); 409 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req) 410 { 411 kref_get(&req->r_kref); 412 } 413 extern void ceph_mdsc_release_request(struct kref *kref); 414 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req) 415 { 416 kref_put(&req->r_kref, ceph_mdsc_release_request); 417 } 418 419 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc, 420 struct ceph_mds_session *session); 421 422 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc); 423 424 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base, 425 int stop_on_nosnap); 426 427 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry); 428 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session, 429 struct inode *inode, 430 struct dentry *dentry, char action, 431 u32 seq); 432 433 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc, 434 struct ceph_msg *msg); 435 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc, 436 struct ceph_msg *msg); 437 438 extern struct ceph_mds_session * 439 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target); 440 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, 441 struct ceph_mds_session *session); 442 443 #endif 444