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