fs/ceph/mds_client.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _FS_CEPH_MDS_CLIENT_H
   3 #define _FS_CEPH_MDS_CLIENT_H
   4
   5 #include <linux/completion.h>
   6 #include <linux/kref.h>
   7 #include <linux/list.h>
   8 #include <linux/mutex.h>
   9 #include <linux/rbtree.h>
  10 #include <linux/spinlock.h>
  11 #include <linux/refcount.h>
  12 #include <linux/utsname.h>
  13 #include <linux/ktime.h>
  14
  15 #include <linux/ceph/types.h>
  16 #include <linux/ceph/messenger.h>
  17 #include <linux/ceph/auth.h>
  18
  19 #include "mdsmap.h"
  20 #include "metric.h"
  21 #include "super.h"
  22
  23 /* The first 8 bits are reserved for old ceph releases */
  24 enum ceph_feature_type {
  25         CEPHFS_FEATURE_MIMIC = 8,
  26         CEPHFS_FEATURE_REPLY_ENCODING,
  27         CEPHFS_FEATURE_RECLAIM_CLIENT,
  28         CEPHFS_FEATURE_LAZY_CAP_WANTED,
  29         CEPHFS_FEATURE_MULTI_RECONNECT,
  30         CEPHFS_FEATURE_DELEG_INO,
  31         CEPHFS_FEATURE_METRIC_COLLECT,
  32         CEPHFS_FEATURE_ALTERNATE_NAME,
  33         CEPHFS_FEATURE_NOTIFY_SESSION_STATE,
  34         CEPHFS_FEATURE_OP_GETVXATTR,
  35         CEPHFS_FEATURE_32BITS_RETRY_FWD,
  36         CEPHFS_FEATURE_NEW_SNAPREALM_INFO,
  37         CEPHFS_FEATURE_HAS_OWNER_UIDGID,
  38         CEPHFS_FEATURE_MDS_AUTH_CAPS_CHECK,
  39
  40         CEPHFS_FEATURE_MAX = CEPHFS_FEATURE_MDS_AUTH_CAPS_CHECK,
  41 };
  42
  43 #define CEPHFS_FEATURES_CLIENT_SUPPORTED {      \
  44         0, 1, 2, 3, 4, 5, 6, 7,                 \
  45         CEPHFS_FEATURE_MIMIC,                   \
  46         CEPHFS_FEATURE_REPLY_ENCODING,          \
  47         CEPHFS_FEATURE_LAZY_CAP_WANTED,         \
  48         CEPHFS_FEATURE_MULTI_RECONNECT,         \
  49         CEPHFS_FEATURE_DELEG_INO,               \
  50         CEPHFS_FEATURE_METRIC_COLLECT,          \
  51         CEPHFS_FEATURE_ALTERNATE_NAME,          \
  52         CEPHFS_FEATURE_NOTIFY_SESSION_STATE,    \
  53         CEPHFS_FEATURE_OP_GETVXATTR,            \
  54         CEPHFS_FEATURE_32BITS_RETRY_FWD,        \
  55         CEPHFS_FEATURE_HAS_OWNER_UIDGID,        \
  56         CEPHFS_FEATURE_MDS_AUTH_CAPS_CHECK,     \
  57 }
  58
  59 /*
  60  * Some lock dependencies:
  61  *
  62  * session->s_mutex
  63  *         mdsc->mutex
  64  *
  65  *         mdsc->snap_rwsem
  66  *
  67  *         ci->i_ceph_lock
  68  *                 mdsc->snap_flush_lock
  69  *                 mdsc->cap_delay_lock
  70  *
  71  */
  72
  73 struct ceph_fs_client;
  74 struct ceph_cap;
  75
  76 #define MDS_AUTH_UID_ANY -1
  77
  78 struct ceph_mds_cap_match {
  79         s64 uid;  /* default to MDS_AUTH_UID_ANY */
  80         u32 num_gids;
  81         u32 *gids;  /* use these GIDs */
  82         char *path;  /* require path to be child of this
  83                         (may be "" or "/" for any) */
  84         char *fs_name;
  85         bool root_squash;  /* default to false */
  86 };
  87
  88 struct ceph_mds_cap_auth {
  89         struct ceph_mds_cap_match match;
  90         bool readable;
  91         bool writeable;
  92 };
  93
  94 /*
  95  * parsed info about a single inode.  pointers are into the encoded
  96  * on-wire structures within the mds reply message payload.
  97  */
  98 struct ceph_mds_reply_info_in {
  99         struct ceph_mds_reply_inode *in;
 100         struct ceph_dir_layout dir_layout;
 101         u32 symlink_len;
 102         char *symlink;
 103         u32 xattr_len;
 104         char *xattr_data;
 105         u64 inline_version;
 106         u32 inline_len;
 107         char *inline_data;
 108         u32 pool_ns_len;
 109         char *pool_ns_data;
 110         u64 max_bytes;
 111         u64 max_files;
 112         s32 dir_pin;
 113         struct ceph_timespec btime;
 114         struct ceph_timespec snap_btime;
 115         u8 *fscrypt_auth;
 116         u8 *fscrypt_file;
 117         u32 fscrypt_auth_len;
 118         u32 fscrypt_file_len;
 119         u64 rsnaps;
 120         u64 change_attr;
 121 };
 122
 123 struct ceph_mds_reply_dir_entry {
 124         bool                          is_nokey;
 125         char                          *name;
 126         u32                           name_len;
 127         u32                           raw_hash;
 128         struct ceph_mds_reply_lease   *lease;
 129         struct ceph_mds_reply_info_in inode;
 130         loff_t                        offset;
 131 };
 132
 133 struct ceph_mds_reply_xattr {
 134         char *xattr_value;
 135         size_t xattr_value_len;
 136 };
 137
 138 /*
 139  * parsed info about an mds reply, including information about
 140  * either: 1) the target inode and/or its parent directory and dentry,
 141  * and directory contents (for readdir results), or
 142  * 2) the file range lock info (for fcntl F_GETLK results).
 143  */
 144 struct ceph_mds_reply_info_parsed {
 145         struct ceph_mds_reply_head    *head;
 146
 147         /* trace */
 148         struct ceph_mds_reply_info_in diri, targeti;
 149         struct ceph_mds_reply_dirfrag *dirfrag;
 150         char                          *dname;
 151         u8                            *altname;
 152         u32                           dname_len;
 153         u32                           altname_len;
 154         struct ceph_mds_reply_lease   *dlease;
 155         struct ceph_mds_reply_xattr   xattr_info;
 156
 157         /* extra */
 158         union {
 159                 /* for fcntl F_GETLK results */
 160                 struct ceph_filelock *filelock_reply;
 161
 162                 /* for readdir results */
 163                 struct {
 164                         struct ceph_mds_reply_dirfrag *dir_dir;
 165                         size_t                        dir_buf_size;
 166                         int                           dir_nr;
 167                         bool                          dir_end;
 168                         bool                          dir_complete;
 169                         bool                          hash_order;
 170                         bool                          offset_hash;
 171                         struct ceph_mds_reply_dir_entry  *dir_entries;
 172                 };
 173
 174                 /* for create results */
 175                 struct {
 176                         bool has_create_ino;
 177                         u64 ino;
 178                 };
 179         };
 180
 181         /* encoded blob describing snapshot contexts for certain
 182            operations (e.g., open) */
 183         void *snapblob;
 184         int snapblob_len;
 185 };
 186
 187
 188 /*
 189  * cap releases are batched and sent to the MDS en masse.
 190  *
 191  * Account for per-message overhead of mds_cap_release header
 192  * and __le32 for osd epoch barrier trailing field.
 193  */
 194 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) -               \
 195                                 sizeof(struct ceph_mds_cap_release)) /  \
 196                                 sizeof(struct ceph_mds_cap_item))
 197
 198
 199 /*
 200  * state associated with each MDS<->client session
 201  */
 202 enum {
 203         CEPH_MDS_SESSION_NEW = 1,
 204         CEPH_MDS_SESSION_OPENING = 2,
 205         CEPH_MDS_SESSION_OPEN = 3,
 206         CEPH_MDS_SESSION_HUNG = 4,
 207         CEPH_MDS_SESSION_RESTARTING = 5,
 208         CEPH_MDS_SESSION_RECONNECTING = 6,
 209         CEPH_MDS_SESSION_CLOSING = 7,
 210         CEPH_MDS_SESSION_CLOSED = 8,
 211         CEPH_MDS_SESSION_REJECTED = 9,
 212 };
 213
 214 struct ceph_mds_session {
 215         struct ceph_mds_client *s_mdsc;
 216         int               s_mds;
 217         int               s_state;
 218         unsigned long     s_ttl;      /* time until mds kills us */
 219         unsigned long     s_features;
 220         u64               s_seq;      /* incoming msg seq # */
 221         struct mutex      s_mutex;    /* serialize session messages */
 222
 223         struct ceph_connection s_con;
 224
 225         struct ceph_auth_handshake s_auth;
 226
 227         atomic_t          s_cap_gen;  /* inc each time we get mds stale msg */
 228         unsigned long     s_cap_ttl;  /* when session caps expire. protected by s_mutex */
 229
 230         /* protected by s_cap_lock */
 231         spinlock_t        s_cap_lock;
 232         refcount_t        s_ref;
 233         struct list_head  s_caps;     /* all caps issued by this session */
 234         struct ceph_cap  *s_cap_iterator;
 235         int               s_nr_caps;
 236         int               s_num_cap_releases;
 237         int               s_cap_reconnect;
 238         int               s_readonly;
 239         struct list_head  s_cap_releases; /* waiting cap_release messages */
 240         struct work_struct s_cap_release_work;
 241
 242         /* See ceph_inode_info->i_dirty_item. */
 243         struct list_head  s_cap_dirty;        /* inodes w/ dirty caps */
 244
 245         /* See ceph_inode_info->i_flushing_item. */
 246         struct list_head  s_cap_flushing;     /* inodes w/ flushing caps */
 247
 248         unsigned long     s_renew_requested; /* last time we sent a renew req */
 249         u64               s_renew_seq;
 250
 251         struct list_head  s_waiting;  /* waiting requests */
 252         struct list_head  s_unsafe;   /* unsafe requests */
 253         struct xarray     s_delegated_inos;
 254 };
 255
 256 /*
 257  * modes of choosing which MDS to send a request to
 258  */
 259 enum {
 260         USE_ANY_MDS,
 261         USE_RANDOM_MDS,
 262         USE_AUTH_MDS,   /* prefer authoritative mds for this metadata item */
 263 };
 264
 265 struct ceph_mds_request;
 266 struct ceph_mds_client;
 267
 268 /*
 269  * request completion callback
 270  */
 271 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
 272                                              struct ceph_mds_request *req);
 273 /*
 274  * wait for request completion callback
 275  */
 276 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
 277                                                  struct ceph_mds_request *req);
 278
 279 /*
 280  * an in-flight mds request
 281  */
 282 struct ceph_mds_request {
 283         u64 r_tid;                   /* transaction id */
 284         struct rb_node r_node;
 285         struct ceph_mds_client *r_mdsc;
 286
 287         struct kref       r_kref;
 288         int r_op;                    /* mds op code */
 289
 290         /* operation on what? */
 291         struct inode *r_inode;              /* arg1 */
 292         struct dentry *r_dentry;            /* arg1 */
 293         struct dentry *r_old_dentry;        /* arg2: rename from or link from */
 294         struct inode *r_old_dentry_dir;     /* arg2: old dentry's parent dir */
 295         char *r_path1, *r_path2;
 296         struct ceph_vino r_ino1, r_ino2;
 297
 298         struct inode *r_parent;             /* parent dir inode */
 299         struct inode *r_target_inode;       /* resulting inode */
 300         struct inode *r_new_inode;          /* new inode (for creates) */
 301
 302 #define CEPH_MDS_R_DIRECT_IS_HASH       (1) /* r_direct_hash is valid */
 303 #define CEPH_MDS_R_ABORTED              (2) /* call was aborted */
 304 #define CEPH_MDS_R_GOT_UNSAFE           (3) /* got an unsafe reply */
 305 #define CEPH_MDS_R_GOT_SAFE             (4) /* got a safe reply */
 306 #define CEPH_MDS_R_GOT_RESULT           (5) /* got a result */
 307 #define CEPH_MDS_R_DID_PREPOPULATE      (6) /* prepopulated readdir */
 308 #define CEPH_MDS_R_PARENT_LOCKED        (7) /* is r_parent->i_rwsem wlocked? */
 309 #define CEPH_MDS_R_ASYNC                (8) /* async request */
 310 #define CEPH_MDS_R_FSCRYPT_FILE         (9) /* must marshal fscrypt_file field */
 311         unsigned long   r_req_flags;
 312
 313         struct mutex r_fill_mutex;
 314
 315         union ceph_mds_request_args r_args;
 316
 317         struct ceph_fscrypt_auth *r_fscrypt_auth;
 318         u64     r_fscrypt_file;
 319
 320         u8 *r_altname;              /* fscrypt binary crypttext for long filenames */
 321         u32 r_altname_len;          /* length of r_altname */
 322
 323         int r_fmode;        /* file mode, if expecting cap */
 324         int r_request_release_offset;
 325         const struct cred *r_cred;
 326         struct mnt_idmap *r_mnt_idmap;
 327         struct timespec64 r_stamp;
 328
 329         /* for choosing which mds to send this request to */
 330         int r_direct_mode;
 331         u32 r_direct_hash;      /* choose dir frag based on this dentry hash */
 332
 333         /* data payload is used for xattr ops */
 334         struct ceph_pagelist *r_pagelist;
 335
 336         /* what caps shall we drop? */
 337         int r_inode_drop, r_inode_unless;
 338         int r_dentry_drop, r_dentry_unless;
 339         int r_old_dentry_drop, r_old_dentry_unless;
 340         struct inode *r_old_inode;
 341         int r_old_inode_drop, r_old_inode_unless;
 342
 343         struct ceph_msg  *r_request;  /* original request */
 344         struct ceph_msg  *r_reply;
 345         struct ceph_mds_reply_info_parsed r_reply_info;
 346         int r_err;
 347         u32               r_readdir_offset;
 348
 349         struct page *r_locked_page;
 350         int r_dir_caps;
 351         int r_num_caps;
 352
 353         unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */
 354         unsigned long r_started;  /* start time to measure timeout against */
 355         unsigned long r_start_latency;  /* start time to measure latency */
 356         unsigned long r_end_latency;    /* finish time to measure latency */
 357         unsigned long r_request_started; /* start time for mds request only,
 358                                             used to measure lease durations */
 359
 360         /* link unsafe requests to parent directory, for fsync */
 361         struct inode    *r_unsafe_dir;
 362         struct list_head r_unsafe_dir_item;
 363
 364         /* unsafe requests that modify the target inode */
 365         struct list_head r_unsafe_target_item;
 366
 367         struct ceph_mds_session *r_session;
 368
 369         int               r_attempts;   /* resend attempts */
 370         int               r_num_fwd;    /* number of forward attempts */
 371         int               r_resend_mds; /* mds to resend to next, if any*/
 372         u32               r_sent_on_mseq; /* cap mseq request was sent at*/
 373         u64               r_deleg_ino;
 374
 375         struct list_head  r_wait;
 376         struct completion r_completion;
 377         struct completion r_safe_completion;
 378         ceph_mds_request_callback_t r_callback;
 379         struct list_head  r_unsafe_item;  /* per-session unsafe list item */
 380
 381         long long         r_dir_release_cnt;
 382         long long         r_dir_ordered_cnt;
 383         int               r_readdir_cache_idx;
 384
 385         int               r_feature_needed;
 386
 387         struct ceph_cap_reservation r_caps_reservation;
 388 };
 389
 390 struct ceph_pool_perm {
 391         struct rb_node node;
 392         int perm;
 393         s64 pool;
 394         size_t pool_ns_len;
 395         char pool_ns[];
 396 };
 397
 398 struct ceph_snapid_map {
 399         struct rb_node node;
 400         struct list_head lru;
 401         atomic_t ref;
 402         dev_t dev;
 403         u64 snap;
 404         unsigned long last_used;
 405 };
 406
 407 /*
 408  * node for list of quotarealm inodes that are not visible from the filesystem
 409  * mountpoint, but required to handle, e.g. quotas.
 410  */
 411 struct ceph_quotarealm_inode {
 412         struct rb_node node;
 413         u64 ino;
 414         unsigned long timeout; /* last time a lookup failed for this inode */
 415         struct mutex mutex;
 416         struct inode *inode;
 417 };
 418
 419 #ifdef CONFIG_DEBUG_FS
 420
 421 struct cap_wait {
 422         struct list_head        list;
 423         u64                     ino;
 424         pid_t                   tgid;
 425         int                     need;
 426         int                     want;
 427 };
 428
 429 #endif
 430
 431 enum {
 432         CEPH_MDSC_STOPPING_BEGIN = 1,
 433         CEPH_MDSC_STOPPING_FLUSHING = 2,
 434         CEPH_MDSC_STOPPING_FLUSHED = 3,
 435 };
 436
 437 /*
 438  * mds client state
 439  */
 440 struct ceph_mds_client {
 441         struct ceph_fs_client  *fsc;
 442         struct mutex            mutex;         /* all nested structures */
 443
 444         struct ceph_mdsmap      *mdsmap;
 445         struct completion       safe_umount_waiters;
 446         wait_queue_head_t       session_close_wq;
 447         struct list_head        waiting_for_map;
 448         int                     mdsmap_err;
 449
 450         struct ceph_mds_session **sessions;    /* NULL for mds if no session */
 451         atomic_t                num_sessions;
 452         int                     max_sessions;  /* len of sessions array */
 453
 454         spinlock_t              stopping_lock;  /* protect snap_empty */
 455         int                     stopping;      /* the stage of shutting down */
 456         atomic_t                stopping_blockers;
 457         struct completion       stopping_waiter;
 458
 459         atomic64_t              quotarealms_count; /* # realms with quota */
 460         /*
 461          * We keep a list of inodes we don't see in the mountpoint but that we
 462          * need to track quota realms.
 463          */
 464         struct rb_root          quotarealms_inodes;
 465         struct mutex            quotarealms_inodes_mutex;
 466
 467         /*
 468          * snap_rwsem will cover cap linkage into snaprealms, and
 469          * realm snap contexts.  (later, we can do per-realm snap
 470          * contexts locks..)  the empty list contains realms with no
 471          * references (implying they contain no inodes with caps) that
 472          * should be destroyed.
 473          */
 474         u64                     last_snap_seq;
 475         struct rw_semaphore     snap_rwsem;
 476         struct rb_root          snap_realms;
 477         struct list_head        snap_empty;
 478         int                     num_snap_realms;
 479         spinlock_t              snap_empty_lock;  /* protect snap_empty */
 480
 481         u64                    last_tid;      /* most recent mds request */
 482         u64                    oldest_tid;    /* oldest incomplete mds request,
 483                                                  excluding setfilelock requests */
 484         struct rb_root         request_tree;  /* pending mds requests */
 485         struct delayed_work    delayed_work;  /* delayed work */
 486         unsigned long    last_renew_caps;  /* last time we renewed our caps */
 487         struct list_head cap_delay_list;   /* caps with delayed release */
 488         struct list_head cap_unlink_delay_list;  /* caps with delayed release for unlink */
 489         spinlock_t       cap_delay_lock;   /* protects cap_delay_list and cap_unlink_delay_list */
 490         struct list_head snap_flush_list;  /* cap_snaps ready to flush */
 491         spinlock_t       snap_flush_lock;
 492
 493         u64               last_cap_flush_tid;
 494         struct list_head  cap_flush_list;
 495         struct list_head  cap_dirty_migrating; /* ...that are migration... */
 496         int               num_cap_flushing; /* # caps we are flushing */
 497         spinlock_t        cap_dirty_lock;   /* protects above items */
 498         wait_queue_head_t cap_flushing_wq;
 499
 500         struct work_struct cap_reclaim_work;
 501         atomic_t           cap_reclaim_pending;
 502
 503         struct work_struct cap_unlink_work;
 504
 505         /*
 506          * Cap reservations
 507          *
 508          * Maintain a global pool of preallocated struct ceph_caps, referenced
 509          * by struct ceph_caps_reservations.  This ensures that we preallocate
 510          * memory needed to successfully process an MDS response.  (If an MDS
 511          * sends us cap information and we fail to process it, we will have
 512          * problems due to the client and MDS being out of sync.)
 513          *
 514          * Reservations are 'owned' by a ceph_cap_reservation context.
 515          */
 516         spinlock_t      caps_list_lock;
 517         struct          list_head caps_list; /* unused (reserved or
 518                                                 unreserved) */
 519 #ifdef CONFIG_DEBUG_FS
 520         struct          list_head cap_wait_list;
 521 #endif
 522         int             caps_total_count;    /* total caps allocated */
 523         int             caps_use_count;      /* in use */
 524         int             caps_use_max;        /* max used caps */
 525         int             caps_reserve_count;  /* unused, reserved */
 526         int             caps_avail_count;    /* unused, unreserved */
 527         int             caps_min_count;      /* keep at least this many
 528                                                 (unreserved) */
 529         spinlock_t        dentry_list_lock;
 530         struct list_head  dentry_leases;     /* fifo list */
 531         struct list_head  dentry_dir_leases; /* lru list */
 532
 533         struct ceph_client_metric metric;
 534
 535         spinlock_t              snapid_map_lock;
 536         struct rb_root          snapid_map_tree;
 537         struct list_head        snapid_map_lru;
 538
 539         struct rw_semaphore     pool_perm_rwsem;
 540         struct rb_root          pool_perm_tree;
 541
 542         u32                      s_cap_auths_num;
 543         struct ceph_mds_cap_auth *s_cap_auths;
 544
 545         char nodename[__NEW_UTS_LEN + 1];
 546 };
 547
 548 extern const char *ceph_mds_op_name(int op);
 549
 550 extern bool check_session_state(struct ceph_mds_session *s);
 551 void inc_session_sequence(struct ceph_mds_session *s);
 552
 553 extern struct ceph_mds_session *
 554 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
 555
 556 extern const char *ceph_session_state_name(int s);
 557
 558 extern struct ceph_mds_session *
 559 ceph_get_mds_session(struct ceph_mds_session *s);
 560 extern void ceph_put_mds_session(struct ceph_mds_session *s);
 561
 562 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
 563 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
 564 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
 565 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
 566
 567 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
 568
 569 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
 570 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
 571                                            struct inode *dir);
 572 extern struct ceph_mds_request *
 573 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
 574 extern int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
 575                                     struct inode *dir,
 576                                     struct ceph_mds_request *req);
 577 int ceph_mdsc_wait_request(struct ceph_mds_client *mdsc,
 578                         struct ceph_mds_request *req,
 579                         ceph_mds_request_wait_callback_t wait_func);
 580 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
 581                                 struct inode *dir,
 582                                 struct ceph_mds_request *req);
 583 extern void ceph_mdsc_release_dir_caps(struct ceph_mds_request *req);
 584 extern void ceph_mdsc_release_dir_caps_async(struct ceph_mds_request *req);
 585 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
 586 {
 587         kref_get(&req->r_kref);
 588 }
 589 extern void ceph_mdsc_release_request(struct kref *kref);
 590 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
 591 {
 592         kref_put(&req->r_kref, ceph_mdsc_release_request);
 593 }
 594
 595 extern void send_flush_mdlog(struct ceph_mds_session *s);
 596 extern void ceph_mdsc_iterate_sessions(struct ceph_mds_client *mdsc,
 597                                        void (*cb)(struct ceph_mds_session *),
 598                                        bool check_state);
 599 extern struct ceph_msg *ceph_create_session_msg(u32 op, u64 seq);
 600 extern void __ceph_queue_cap_release(struct ceph_mds_session *session,
 601                                     struct ceph_cap *cap);
 602 extern void ceph_flush_session_cap_releases(struct ceph_mds_client *mdsc,
 603                                             struct ceph_mds_session *session);
 604 extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
 605 extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
 606 extern void ceph_queue_cap_unlink_work(struct ceph_mds_client *mdsc);
 607 extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
 608                                      int (*cb)(struct inode *, int mds, void *),
 609                                      void *arg);
 610 extern int ceph_mds_check_access(struct ceph_mds_client *mdsc, char *tpath,
 611                                  int mask);
 612
 613 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
 614
 615 static inline void ceph_mdsc_free_path(char *path, int len)
 616 {
 617         if (!IS_ERR_OR_NULL(path))
 618                 __putname(path - (PATH_MAX - 1 - len));
 619 }
 620
 621 extern char *ceph_mdsc_build_path(struct ceph_mds_client *mdsc,
 622                                   struct dentry *dentry, int *plen, u64 *base,
 623                                   int for_wire);
 624
 625 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
 626 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
 627                                      struct dentry *dentry, char action,
 628                                      u32 seq);
 629
 630 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
 631                                     struct ceph_msg *msg);
 632 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
 633                                    struct ceph_msg *msg);
 634
 635 extern struct ceph_mds_session *
 636 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
 637 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
 638                                           struct ceph_mds_session *session);
 639
 640 extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
 641                           struct ceph_mds_session *session,
 642                           int max_caps);
 643
 644 static inline int ceph_wait_on_async_create(struct inode *inode)
 645 {
 646         struct ceph_inode_info *ci = ceph_inode(inode);
 647
 648         return wait_on_bit(&ci->i_ceph_flags, CEPH_ASYNC_CREATE_BIT,
 649                            TASK_KILLABLE);
 650 }
 651
 652 extern int ceph_wait_on_conflict_unlink(struct dentry *dentry);
 653 extern u64 ceph_get_deleg_ino(struct ceph_mds_session *session);
 654 extern int ceph_restore_deleg_ino(struct ceph_mds_session *session, u64 ino);
 655
 656 extern bool enable_unsafe_idmap;
 657 #endif