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 /* 51 * parsed info about an mds reply, including information about 52 * either: 1) the target inode and/or its parent directory and dentry, 53 * and directory contents (for readdir results), or 54 * 2) the file range lock info (for fcntl F_GETLK results). 55 */ 56 struct ceph_mds_reply_info_parsed { 57 struct ceph_mds_reply_head *head; 58 59 /* trace */ 60 struct ceph_mds_reply_info_in diri, targeti; 61 struct ceph_mds_reply_dirfrag *dirfrag; 62 char *dname; 63 u32 dname_len; 64 struct ceph_mds_reply_lease *dlease; 65 66 /* extra */ 67 union { 68 /* for fcntl F_GETLK results */ 69 struct ceph_filelock *filelock_reply; 70 71 /* for readdir results */ 72 struct { 73 struct ceph_mds_reply_dirfrag *dir_dir; 74 size_t dir_buf_size; 75 int dir_nr; 76 char **dir_dname; 77 u32 *dir_dname_len; 78 struct ceph_mds_reply_lease **dir_dlease; 79 struct ceph_mds_reply_info_in *dir_in; 80 u8 dir_complete, dir_end; 81 }; 82 83 /* for create results */ 84 struct { 85 bool has_create_ino; 86 u64 ino; 87 }; 88 }; 89 90 /* encoded blob describing snapshot contexts for certain 91 operations (e.g., open) */ 92 void *snapblob; 93 int snapblob_len; 94 }; 95 96 97 /* 98 * cap releases are batched and sent to the MDS en masse. 99 */ 100 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - \ 101 sizeof(struct ceph_mds_cap_release)) / \ 102 sizeof(struct ceph_mds_cap_item)) 103 104 105 /* 106 * state associated with each MDS<->client session 107 */ 108 enum { 109 CEPH_MDS_SESSION_NEW = 1, 110 CEPH_MDS_SESSION_OPENING = 2, 111 CEPH_MDS_SESSION_OPEN = 3, 112 CEPH_MDS_SESSION_HUNG = 4, 113 CEPH_MDS_SESSION_CLOSING = 5, 114 CEPH_MDS_SESSION_RESTARTING = 6, 115 CEPH_MDS_SESSION_RECONNECTING = 7, 116 }; 117 118 struct ceph_mds_session { 119 struct ceph_mds_client *s_mdsc; 120 int s_mds; 121 int s_state; 122 unsigned long s_ttl; /* time until mds kills us */ 123 u64 s_seq; /* incoming msg seq # */ 124 struct mutex s_mutex; /* serialize session messages */ 125 126 struct ceph_connection s_con; 127 128 struct ceph_auth_handshake s_auth; 129 130 /* protected by s_gen_ttl_lock */ 131 spinlock_t s_gen_ttl_lock; 132 u32 s_cap_gen; /* inc each time we get mds stale msg */ 133 unsigned long s_cap_ttl; /* when session caps expire */ 134 135 /* protected by s_cap_lock */ 136 spinlock_t s_cap_lock; 137 struct list_head s_caps; /* all caps issued by this session */ 138 int s_nr_caps, s_trim_caps; 139 int s_num_cap_releases; 140 int s_cap_reconnect; 141 int s_readonly; 142 struct list_head s_cap_releases; /* waiting cap_release messages */ 143 struct ceph_cap *s_cap_iterator; 144 145 /* protected by mutex */ 146 struct list_head s_cap_flushing; /* inodes w/ flushing caps */ 147 struct list_head s_cap_snaps_flushing; 148 unsigned long s_renew_requested; /* last time we sent a renew req */ 149 u64 s_renew_seq; 150 151 atomic_t s_ref; 152 struct list_head s_waiting; /* waiting requests */ 153 struct list_head s_unsafe; /* unsafe requests */ 154 }; 155 156 /* 157 * modes of choosing which MDS to send a request to 158 */ 159 enum { 160 USE_ANY_MDS, 161 USE_RANDOM_MDS, 162 USE_AUTH_MDS, /* prefer authoritative mds for this metadata item */ 163 }; 164 165 struct ceph_mds_request; 166 struct ceph_mds_client; 167 168 /* 169 * request completion callback 170 */ 171 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc, 172 struct ceph_mds_request *req); 173 /* 174 * wait for request completion callback 175 */ 176 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc, 177 struct ceph_mds_request *req); 178 179 /* 180 * an in-flight mds request 181 */ 182 struct ceph_mds_request { 183 u64 r_tid; /* transaction id */ 184 struct rb_node r_node; 185 struct ceph_mds_client *r_mdsc; 186 187 int r_op; /* mds op code */ 188 189 /* operation on what? */ 190 struct inode *r_inode; /* arg1 */ 191 struct dentry *r_dentry; /* arg1 */ 192 struct dentry *r_old_dentry; /* arg2: rename from or link from */ 193 struct inode *r_old_dentry_dir; /* arg2: old dentry's parent dir */ 194 char *r_path1, *r_path2; 195 struct ceph_vino r_ino1, r_ino2; 196 197 struct inode *r_locked_dir; /* dir (if any) i_mutex locked by vfs */ 198 struct inode *r_target_inode; /* resulting inode */ 199 200 struct mutex r_fill_mutex; 201 202 union ceph_mds_request_args r_args; 203 int r_fmode; /* file mode, if expecting cap */ 204 kuid_t r_uid; 205 kgid_t r_gid; 206 struct timespec r_stamp; 207 208 /* for choosing which mds to send this request to */ 209 int r_direct_mode; 210 u32 r_direct_hash; /* choose dir frag based on this dentry hash */ 211 bool r_direct_is_hash; /* true if r_direct_hash is valid */ 212 213 /* data payload is used for xattr ops */ 214 struct ceph_pagelist *r_pagelist; 215 216 /* what caps shall we drop? */ 217 int r_inode_drop, r_inode_unless; 218 int r_dentry_drop, r_dentry_unless; 219 int r_old_dentry_drop, r_old_dentry_unless; 220 struct inode *r_old_inode; 221 int r_old_inode_drop, r_old_inode_unless; 222 223 struct ceph_msg *r_request; /* original request */ 224 int r_request_release_offset; 225 struct ceph_msg *r_reply; 226 struct ceph_mds_reply_info_parsed r_reply_info; 227 struct page *r_locked_page; 228 int r_err; 229 bool r_aborted; 230 231 unsigned long r_timeout; /* optional. jiffies, 0 is "wait forever" */ 232 unsigned long r_started; /* start time to measure timeout against */ 233 unsigned long r_request_started; /* start time for mds request only, 234 used to measure lease durations */ 235 236 /* link unsafe requests to parent directory, for fsync */ 237 struct inode *r_unsafe_dir; 238 struct list_head r_unsafe_dir_item; 239 240 /* unsafe requests that modify the target inode */ 241 struct list_head r_unsafe_target_item; 242 243 struct ceph_mds_session *r_session; 244 245 int r_attempts; /* resend attempts */ 246 int r_num_fwd; /* number of forward attempts */ 247 int r_resend_mds; /* mds to resend to next, if any*/ 248 u32 r_sent_on_mseq; /* cap mseq request was sent at*/ 249 250 struct kref r_kref; 251 struct list_head r_wait; 252 struct completion r_completion; 253 struct completion r_safe_completion; 254 ceph_mds_request_callback_t r_callback; 255 ceph_mds_request_wait_callback_t r_wait_for_completion; 256 struct list_head r_unsafe_item; /* per-session unsafe list item */ 257 bool r_got_unsafe, r_got_safe, r_got_result; 258 259 bool r_did_prepopulate; 260 long long r_dir_release_cnt; 261 long long r_dir_ordered_cnt; 262 int r_readdir_cache_idx; 263 u32 r_readdir_offset; 264 265 struct ceph_cap_reservation r_caps_reservation; 266 int r_num_caps; 267 }; 268 269 struct ceph_pool_perm { 270 struct rb_node node; 271 u32 pool; 272 int perm; 273 }; 274 275 /* 276 * mds client state 277 */ 278 struct ceph_mds_client { 279 struct ceph_fs_client *fsc; 280 struct mutex mutex; /* all nested structures */ 281 282 struct ceph_mdsmap *mdsmap; 283 struct completion safe_umount_waiters; 284 wait_queue_head_t session_close_wq; 285 struct list_head waiting_for_map; 286 287 struct ceph_mds_session **sessions; /* NULL for mds if no session */ 288 atomic_t num_sessions; 289 int max_sessions; /* len of s_mds_sessions */ 290 int stopping; /* true if shutting down */ 291 292 /* 293 * snap_rwsem will cover cap linkage into snaprealms, and 294 * realm snap contexts. (later, we can do per-realm snap 295 * contexts locks..) the empty list contains realms with no 296 * references (implying they contain no inodes with caps) that 297 * should be destroyed. 298 */ 299 u64 last_snap_seq; 300 struct rw_semaphore snap_rwsem; 301 struct rb_root snap_realms; 302 struct list_head snap_empty; 303 spinlock_t snap_empty_lock; /* protect snap_empty */ 304 305 u64 last_tid; /* most recent mds request */ 306 u64 oldest_tid; /* oldest incomplete mds request, 307 excluding setfilelock requests */ 308 struct rb_root request_tree; /* pending mds requests */ 309 struct delayed_work delayed_work; /* delayed work */ 310 unsigned long last_renew_caps; /* last time we renewed our caps */ 311 struct list_head cap_delay_list; /* caps with delayed release */ 312 spinlock_t cap_delay_lock; /* protects cap_delay_list */ 313 struct list_head snap_flush_list; /* cap_snaps ready to flush */ 314 spinlock_t snap_flush_lock; 315 316 u64 last_cap_flush_tid; 317 struct rb_root cap_flush_tree; 318 struct list_head cap_dirty; /* inodes with dirty caps */ 319 struct list_head cap_dirty_migrating; /* ...that are migration... */ 320 int num_cap_flushing; /* # caps we are flushing */ 321 spinlock_t cap_dirty_lock; /* protects above items */ 322 wait_queue_head_t cap_flushing_wq; 323 324 /* 325 * Cap reservations 326 * 327 * Maintain a global pool of preallocated struct ceph_caps, referenced 328 * by struct ceph_caps_reservations. This ensures that we preallocate 329 * memory needed to successfully process an MDS response. (If an MDS 330 * sends us cap information and we fail to process it, we will have 331 * problems due to the client and MDS being out of sync.) 332 * 333 * Reservations are 'owned' by a ceph_cap_reservation context. 334 */ 335 spinlock_t caps_list_lock; 336 struct list_head caps_list; /* unused (reserved or 337 unreserved) */ 338 int caps_total_count; /* total caps allocated */ 339 int caps_use_count; /* in use */ 340 int caps_reserve_count; /* unused, reserved */ 341 int caps_avail_count; /* unused, unreserved */ 342 int caps_min_count; /* keep at least this many 343 (unreserved) */ 344 spinlock_t dentry_lru_lock; 345 struct list_head dentry_lru; 346 int num_dentry; 347 348 struct rw_semaphore pool_perm_rwsem; 349 struct rb_root pool_perm_tree; 350 }; 351 352 extern const char *ceph_mds_op_name(int op); 353 354 extern struct ceph_mds_session * 355 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds); 356 357 static inline struct ceph_mds_session * 358 ceph_get_mds_session(struct ceph_mds_session *s) 359 { 360 atomic_inc(&s->s_ref); 361 return s; 362 } 363 364 extern const char *ceph_session_state_name(int s); 365 366 extern void ceph_put_mds_session(struct ceph_mds_session *s); 367 368 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc, 369 struct ceph_msg *msg, int mds); 370 371 extern int ceph_mdsc_init(struct ceph_fs_client *fsc); 372 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc); 373 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc); 374 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc); 375 376 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc); 377 378 extern void ceph_mdsc_lease_release(struct ceph_mds_client *mdsc, 379 struct inode *inode, 380 struct dentry *dn); 381 382 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req); 383 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req, 384 struct inode *dir); 385 extern struct ceph_mds_request * 386 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode); 387 extern void ceph_mdsc_submit_request(struct ceph_mds_client *mdsc, 388 struct ceph_mds_request *req); 389 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc, 390 struct inode *dir, 391 struct ceph_mds_request *req); 392 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req) 393 { 394 kref_get(&req->r_kref); 395 } 396 extern void ceph_mdsc_release_request(struct kref *kref); 397 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req) 398 { 399 kref_put(&req->r_kref, ceph_mdsc_release_request); 400 } 401 402 extern void ceph_send_cap_releases(struct ceph_mds_client *mdsc, 403 struct ceph_mds_session *session); 404 405 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc); 406 407 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base, 408 int stop_on_nosnap); 409 410 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry); 411 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session, 412 struct inode *inode, 413 struct dentry *dentry, char action, 414 u32 seq); 415 416 extern void ceph_mdsc_handle_map(struct ceph_mds_client *mdsc, 417 struct ceph_msg *msg); 418 419 extern struct ceph_mds_session * 420 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target); 421 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc, 422 struct ceph_mds_session *session); 423 424 #endif 425