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 }; 49 50 struct ceph_mds_reply_dir_entry { 51 char *name; 52 u32 name_len; 53 struct ceph_mds_reply_lease *lease; 54 struct ceph_mds_reply_info_in inode; 55 loff_t offset; 56 }; 57 58 /* 59 * parsed info about an mds reply, including information about 60 * either: 1) the target inode and/or its parent directory and dentry, 61 * and directory contents (for readdir results), or 62 * 2) the file range lock info (for fcntl F_GETLK results). 63 */ 64 struct ceph_mds_reply_info_parsed { 65 struct ceph_mds_reply_head *head; 66 67 /* trace */ 68 struct ceph_mds_reply_info_in diri, targeti; 69 struct ceph_mds_reply_dirfrag *dirfrag; 70 char *dname; 71 u32 dname_len; 72 struct ceph_mds_reply_lease *dlease; 73 74 /* extra */ 75 union { 76 /* for fcntl F_GETLK results */ 77 struct ceph_filelock *filelock_reply; 78 79 /* for readdir results */ 80 struct { 81 struct ceph_mds_reply_dirfrag *dir_dir; 82 size_t dir_buf_size; 83 int dir_nr; 84 bool dir_complete; 85 bool dir_end; 86 bool hash_order; 87 struct ceph_mds_reply_dir_entry *dir_entries; 88 }; 89 90 /* for create results */ 91 struct { 92 bool has_create_ino; 93 u64 ino; 94 }; 95 }; 96 97 /* encoded blob describing snapshot contexts for certain 98 operations (e.g., open) */ 99 void *snapblob; 100 int snapblob_len; 101 }; 102 103 104 /* 105 * cap releases are batched and sent to the MDS en masse. 106 */ 107 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - \ 108 sizeof(struct ceph_mds_cap_release)) / \ 109 sizeof(struct ceph_mds_cap_item)) 110 111 112 /* 113 * state associated with each MDS<->client session 114 */ 115 enum { 116 CEPH_MDS_SESSION_NEW = 1, 117 CEPH_MDS_SESSION_OPENING = 2, 118 CEPH_MDS_SESSION_OPEN = 3, 119 CEPH_MDS_SESSION_HUNG = 4, 120 CEPH_MDS_SESSION_CLOSING = 5, 121 CEPH_MDS_SESSION_RESTARTING = 6, 122 CEPH_MDS_SESSION_RECONNECTING = 7, 123 }; 124 125 struct ceph_mds_session { 126 struct ceph_mds_client *s_mdsc; 127 int s_mds; 128 int s_state; 129 unsigned long s_ttl; /* time until mds kills us */ 130 u64 s_seq; /* incoming msg seq # */ 131 struct mutex s_mutex; /* serialize session messages */ 132 133 struct ceph_connection s_con; 134 135 struct ceph_auth_handshake s_auth; 136 137 /* protected by s_gen_ttl_lock */ 138 spinlock_t s_gen_ttl_lock; 139 u32 s_cap_gen; /* inc each time we get mds stale msg */ 140 unsigned long s_cap_ttl; /* when session caps expire */ 141 142 /* protected by s_cap_lock */ 143 spinlock_t s_cap_lock; 144 struct list_head s_caps; /* all caps issued by this session */ 145 int s_nr_caps, s_trim_caps; 146 int s_num_cap_releases; 147 int s_cap_reconnect; 148 int s_readonly; 149 struct list_head s_cap_releases; /* waiting cap_release messages */ 150 struct ceph_cap *s_cap_iterator; 151 152 /* protected by mutex */ 153 struct list_head s_cap_flushing; /* inodes w/ flushing caps */ 154 struct list_head s_cap_snaps_flushing; 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 u32 pool; 279 int perm; 280 }; 281 282 /* 283 * mds client state 284 */ 285 struct ceph_mds_client { 286 struct ceph_fs_client *fsc; 287 struct mutex mutex; /* all nested structures */ 288 289 struct ceph_mdsmap *mdsmap; 290 struct completion safe_umount_waiters; 291 wait_queue_head_t session_close_wq; 292 struct list_head waiting_for_map; 293 294 struct ceph_mds_session **sessions; /* NULL for mds if no session */ 295 atomic_t num_sessions; 296 int max_sessions; /* len of s_mds_sessions */ 297 int stopping; /* true if shutting down */ 298 299 /* 300 * snap_rwsem will cover cap linkage into snaprealms, and 301 * realm snap contexts. (later, we can do per-realm snap 302 * contexts locks..) the empty list contains realms with no 303 * references (implying they contain no inodes with caps) that 304 * should be destroyed. 305 */ 306 u64 last_snap_seq; 307 struct rw_semaphore snap_rwsem; 308 struct rb_root snap_realms; 309 struct list_head snap_empty; 310 spinlock_t snap_empty_lock; /* protect snap_empty */ 311 312 u64 last_tid; /* most recent mds request */ 313 u64 oldest_tid; /* oldest incomplete mds request, 314 excluding setfilelock requests */ 315 struct rb_root request_tree; /* pending mds requests */ 316 struct delayed_work delayed_work; /* delayed work */ 317 unsigned long last_renew_caps; /* last time we renewed our caps */ 318 struct list_head cap_delay_list; /* caps with delayed release */ 319 spinlock_t cap_delay_lock; /* protects cap_delay_list */ 320 struct list_head snap_flush_list; /* cap_snaps ready to flush */ 321 spinlock_t snap_flush_lock; 322 323 u64 last_cap_flush_tid; 324 struct rb_root cap_flush_tree; 325 struct list_head cap_dirty; /* inodes with dirty caps */ 326 struct list_head cap_dirty_migrating; /* ...that are migration... */ 327 int num_cap_flushing; /* # caps we are flushing */ 328 spinlock_t cap_dirty_lock; /* protects above items */ 329 wait_queue_head_t cap_flushing_wq; 330 331 /* 332 * Cap reservations 333 * 334 * Maintain a global pool of preallocated struct ceph_caps, referenced 335 * by struct ceph_caps_reservations. This ensures that we preallocate 336 * memory needed to successfully process an MDS response. (If an MDS 337 * sends us cap information and we fail to process it, we will have 338 * problems due to the client and MDS being out of sync.) 339 * 340 * Reservations are 'owned' by a ceph_cap_reservation context. 341 */ 342 spinlock_t caps_list_lock; 343 struct list_head caps_list; /* unused (reserved or 344 unreserved) */ 345 int caps_total_count; /* total caps allocated */ 346 int caps_use_count; /* in use */ 347 int caps_reserve_count; /* unused, reserved */ 348 int caps_avail_count; /* unused, unreserved */ 349 int caps_min_count; /* keep at least this many 350 (unreserved) */ 351 spinlock_t dentry_lru_lock; 352 struct list_head dentry_lru; 353 int num_dentry; 354 355 struct rw_semaphore pool_perm_rwsem; 356 struct rb_root pool_perm_tree; 357 }; 358 359 extern const char *ceph_mds_op_name(int op); 360 361 extern struct ceph_mds_session * 362 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds); 363 364 static inline struct ceph_mds_session * 365 ceph_get_mds_session(struct ceph_mds_session *s) 366 { 367 atomic_inc(&s->s_ref); 368 return s; 369 } 370 371 extern const char *ceph_session_state_name(int s); 372 373 extern void ceph_put_mds_session(struct ceph_mds_session *s); 374 375 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc, 376 struct ceph_msg *msg, int mds); 377 378 extern int ceph_mdsc_init(struct ceph_fs_client *fsc); 379 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc); 380 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc); 381 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc); 382 383 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc); 384 385 extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, 386 struct inode *inode, 387 struct dentry *dn); 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_map(struct ceph_mds_client *mdsc, 424 struct ceph_msg *msg); 425 426 extern struct ceph_mds_session * 427 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target); 428 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, 429 struct ceph_mds_session *session); 430 431 #endif 432