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