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