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 #define CEPHFS_FEATURE_MIMIC            8
  21 #define CEPHFS_FEATURE_REPLY_ENCODING   9
  22 #define CEPHFS_FEATURE_RECLAIM_CLIENT   10
  23 #define CEPHFS_FEATURE_LAZY_CAP_WANTED  11
  24 #define CEPHFS_FEATURE_MULTI_RECONNECT  12
  25
  26 #define CEPHFS_FEATURES_CLIENT_SUPPORTED {      \
  27         0, 1, 2, 3, 4, 5, 6, 7,                 \
  28         CEPHFS_FEATURE_MIMIC,                   \
  29         CEPHFS_FEATURE_REPLY_ENCODING,          \
  30         CEPHFS_FEATURE_LAZY_CAP_WANTED,         \
  31         CEPHFS_FEATURE_MULTI_RECONNECT,         \
  32 }
  33 #define CEPHFS_FEATURES_CLIENT_REQUIRED {}
  34
  35
  36 /*
  37  * Some lock dependencies:
  38  *
  39  * session->s_mutex
  40  *         mdsc->mutex
  41  *
  42  *         mdsc->snap_rwsem
  43  *
  44  *         ci->i_ceph_lock
  45  *                 mdsc->snap_flush_lock
  46  *                 mdsc->cap_delay_lock
  47  *
  48  */
  49
  50 struct ceph_fs_client;
  51 struct ceph_cap;
  52
  53 /*
  54  * parsed info about a single inode.  pointers are into the encoded
  55  * on-wire structures within the mds reply message payload.
  56  */
  57 struct ceph_mds_reply_info_in {
  58         struct ceph_mds_reply_inode *in;
  59         struct ceph_dir_layout dir_layout;
  60         u32 symlink_len;
  61         char *symlink;
  62         u32 xattr_len;
  63         char *xattr_data;
  64         u64 inline_version;
  65         u32 inline_len;
  66         char *inline_data;
  67         u32 pool_ns_len;
  68         char *pool_ns_data;
  69         u64 max_bytes;
  70         u64 max_files;
  71         s32 dir_pin;
  72 };
  73
  74 struct ceph_mds_reply_dir_entry {
  75         char                          *name;
  76         u32                           name_len;
  77         struct ceph_mds_reply_lease   *lease;
  78         struct ceph_mds_reply_info_in inode;
  79         loff_t                        offset;
  80 };
  81
  82 /*
  83  * parsed info about an mds reply, including information about
  84  * either: 1) the target inode and/or its parent directory and dentry,
  85  * and directory contents (for readdir results), or
  86  * 2) the file range lock info (for fcntl F_GETLK results).
  87  */
  88 struct ceph_mds_reply_info_parsed {
  89         struct ceph_mds_reply_head    *head;
  90
  91         /* trace */
  92         struct ceph_mds_reply_info_in diri, targeti;
  93         struct ceph_mds_reply_dirfrag *dirfrag;
  94         char                          *dname;
  95         u32                           dname_len;
  96         struct ceph_mds_reply_lease   *dlease;
  97
  98         /* extra */
  99         union {
 100                 /* for fcntl F_GETLK results */
 101                 struct ceph_filelock *filelock_reply;
 102
 103                 /* for readdir results */
 104                 struct {
 105                         struct ceph_mds_reply_dirfrag *dir_dir;
 106                         size_t                        dir_buf_size;
 107                         int                           dir_nr;
 108                         bool                          dir_end;
 109                         bool                          dir_complete;
 110                         bool                          hash_order;
 111                         bool                          offset_hash;
 112                         struct ceph_mds_reply_dir_entry  *dir_entries;
 113                 };
 114
 115                 /* for create results */
 116                 struct {
 117                         bool has_create_ino;
 118                         u64 ino;
 119                 };
 120         };
 121
 122         /* encoded blob describing snapshot contexts for certain
 123            operations (e.g., open) */
 124         void *snapblob;
 125         int snapblob_len;
 126 };
 127
 128
 129 /*
 130  * cap releases are batched and sent to the MDS en masse.
 131  *
 132  * Account for per-message overhead of mds_cap_release header
 133  * and __le32 for osd epoch barrier trailing field.
 134  */
 135 #define CEPH_CAPS_PER_RELEASE ((PAGE_SIZE - sizeof(u32) -               \
 136                                 sizeof(struct ceph_mds_cap_release)) /  \
 137                                 sizeof(struct ceph_mds_cap_item))
 138
 139
 140 /*
 141  * state associated with each MDS<->client session
 142  */
 143 enum {
 144         CEPH_MDS_SESSION_NEW = 1,
 145         CEPH_MDS_SESSION_OPENING = 2,
 146         CEPH_MDS_SESSION_OPEN = 3,
 147         CEPH_MDS_SESSION_HUNG = 4,
 148         CEPH_MDS_SESSION_CLOSING = 5,
 149         CEPH_MDS_SESSION_RESTARTING = 6,
 150         CEPH_MDS_SESSION_RECONNECTING = 7,
 151         CEPH_MDS_SESSION_REJECTED = 8,
 152 };
 153
 154 struct ceph_mds_session {
 155         struct ceph_mds_client *s_mdsc;
 156         int               s_mds;
 157         int               s_state;
 158         unsigned long     s_ttl;      /* time until mds kills us */
 159         unsigned long     s_features;
 160         u64               s_seq;      /* incoming msg seq # */
 161         struct mutex      s_mutex;    /* serialize session messages */
 162
 163         struct ceph_connection s_con;
 164
 165         struct ceph_auth_handshake s_auth;
 166
 167         /* protected by s_gen_ttl_lock */
 168         spinlock_t        s_gen_ttl_lock;
 169         u32               s_cap_gen;  /* inc each time we get mds stale msg */
 170         unsigned long     s_cap_ttl;  /* when session caps expire */
 171
 172         /* protected by s_cap_lock */
 173         spinlock_t        s_cap_lock;
 174         struct list_head  s_caps;     /* all caps issued by this session */
 175         struct ceph_cap  *s_cap_iterator;
 176         int               s_nr_caps, s_trim_caps;
 177         int               s_num_cap_releases;
 178         int               s_cap_reconnect;
 179         int               s_readonly;
 180         struct list_head  s_cap_releases; /* waiting cap_release messages */
 181         struct work_struct s_cap_release_work;
 182
 183         /* protected by mutex */
 184         struct list_head  s_cap_flushing;     /* inodes w/ flushing caps */
 185         unsigned long     s_renew_requested; /* last time we sent a renew req */
 186         u64               s_renew_seq;
 187
 188         refcount_t        s_ref;
 189         struct list_head  s_waiting;  /* waiting requests */
 190         struct list_head  s_unsafe;   /* unsafe requests */
 191 };
 192
 193 /*
 194  * modes of choosing which MDS to send a request to
 195  */
 196 enum {
 197         USE_ANY_MDS,
 198         USE_RANDOM_MDS,
 199         USE_AUTH_MDS,   /* prefer authoritative mds for this metadata item */
 200 };
 201
 202 struct ceph_mds_request;
 203 struct ceph_mds_client;
 204
 205 /*
 206  * request completion callback
 207  */
 208 typedef void (*ceph_mds_request_callback_t) (struct ceph_mds_client *mdsc,
 209                                              struct ceph_mds_request *req);
 210 /*
 211  * wait for request completion callback
 212  */
 213 typedef int (*ceph_mds_request_wait_callback_t) (struct ceph_mds_client *mdsc,
 214                                                  struct ceph_mds_request *req);
 215
 216 /*
 217  * an in-flight mds request
 218  */
 219 struct ceph_mds_request {
 220         u64 r_tid;                   /* transaction id */
 221         struct rb_node r_node;
 222         struct ceph_mds_client *r_mdsc;
 223
 224         int r_op;                    /* mds op code */
 225
 226         /* operation on what? */
 227         struct inode *r_inode;              /* arg1 */
 228         struct dentry *r_dentry;            /* arg1 */
 229         struct dentry *r_old_dentry;        /* arg2: rename from or link from */
 230         struct inode *r_old_dentry_dir;     /* arg2: old dentry's parent dir */
 231         char *r_path1, *r_path2;
 232         struct ceph_vino r_ino1, r_ino2;
 233
 234         struct inode *r_parent;             /* parent dir inode */
 235         struct inode *r_target_inode;       /* resulting inode */
 236
 237 #define CEPH_MDS_R_DIRECT_IS_HASH       (1) /* r_direct_hash is valid */
 238 #define CEPH_MDS_R_ABORTED              (2) /* call was aborted */
 239 #define CEPH_MDS_R_GOT_UNSAFE           (3) /* got an unsafe reply */
 240 #define CEPH_MDS_R_GOT_SAFE             (4) /* got a safe reply */
 241 #define CEPH_MDS_R_GOT_RESULT           (5) /* got a result */
 242 #define CEPH_MDS_R_DID_PREPOPULATE      (6) /* prepopulated readdir */
 243 #define CEPH_MDS_R_PARENT_LOCKED        (7) /* is r_parent->i_rwsem wlocked? */
 244         unsigned long   r_req_flags;
 245
 246         struct mutex r_fill_mutex;
 247
 248         union ceph_mds_request_args r_args;
 249         int r_fmode;        /* file mode, if expecting cap */
 250         kuid_t r_uid;
 251         kgid_t r_gid;
 252         struct timespec64 r_stamp;
 253
 254         /* for choosing which mds to send this request to */
 255         int r_direct_mode;
 256         u32 r_direct_hash;      /* choose dir frag based on this dentry hash */
 257
 258         /* data payload is used for xattr ops */
 259         struct ceph_pagelist *r_pagelist;
 260
 261         /* what caps shall we drop? */
 262         int r_inode_drop, r_inode_unless;
 263         int r_dentry_drop, r_dentry_unless;
 264         int r_old_dentry_drop, r_old_dentry_unless;
 265         struct inode *r_old_inode;
 266         int r_old_inode_drop, r_old_inode_unless;
 267
 268         struct ceph_msg  *r_request;  /* original request */
 269         int r_request_release_offset;
 270         struct ceph_msg  *r_reply;
 271         struct ceph_mds_reply_info_parsed r_reply_info;
 272         struct page *r_locked_page;
 273         int r_err;
 274
 275         unsigned long r_timeout;  /* optional.  jiffies, 0 is "wait forever" */
 276         unsigned long r_started;  /* start time to measure timeout against */
 277         unsigned long r_request_started; /* start time for mds request only,
 278                                             used to measure lease durations */
 279
 280         /* link unsafe requests to parent directory, for fsync */
 281         struct inode    *r_unsafe_dir;
 282         struct list_head r_unsafe_dir_item;
 283
 284         /* unsafe requests that modify the target inode */
 285         struct list_head r_unsafe_target_item;
 286
 287         struct ceph_mds_session *r_session;
 288
 289         int               r_attempts;   /* resend attempts */
 290         int               r_num_fwd;    /* number of forward attempts */
 291         int               r_resend_mds; /* mds to resend to next, if any*/
 292         u32               r_sent_on_mseq; /* cap mseq request was sent at*/
 293
 294         struct kref       r_kref;
 295         struct list_head  r_wait;
 296         struct completion r_completion;
 297         struct completion r_safe_completion;
 298         ceph_mds_request_callback_t r_callback;
 299         ceph_mds_request_wait_callback_t r_wait_for_completion;
 300         struct list_head  r_unsafe_item;  /* per-session unsafe list item */
 301
 302         long long         r_dir_release_cnt;
 303         long long         r_dir_ordered_cnt;
 304         int               r_readdir_cache_idx;
 305         u32               r_readdir_offset;
 306
 307         struct ceph_cap_reservation r_caps_reservation;
 308         int r_num_caps;
 309 };
 310
 311 struct ceph_pool_perm {
 312         struct rb_node node;
 313         int perm;
 314         s64 pool;
 315         size_t pool_ns_len;
 316         char pool_ns[];
 317 };
 318
 319 struct ceph_snapid_map {
 320         struct rb_node node;
 321         struct list_head lru;
 322         atomic_t ref;
 323         u64 snap;
 324         dev_t dev;
 325         unsigned long last_used;
 326 };
 327
 328 /*
 329  * node for list of quotarealm inodes that are not visible from the filesystem
 330  * mountpoint, but required to handle, e.g. quotas.
 331  */
 332 struct ceph_quotarealm_inode {
 333         struct rb_node node;
 334         u64 ino;
 335         unsigned long timeout; /* last time a lookup failed for this inode */
 336         struct mutex mutex;
 337         struct inode *inode;
 338 };
 339
 340 /*
 341  * mds client state
 342  */
 343 struct ceph_mds_client {
 344         struct ceph_fs_client  *fsc;
 345         struct mutex            mutex;         /* all nested structures */
 346
 347         struct ceph_mdsmap      *mdsmap;
 348         struct completion       safe_umount_waiters;
 349         wait_queue_head_t       session_close_wq;
 350         struct list_head        waiting_for_map;
 351         int                     mdsmap_err;
 352
 353         struct ceph_mds_session **sessions;    /* NULL for mds if no session */
 354         atomic_t                num_sessions;
 355         int                     max_sessions;  /* len of s_mds_sessions */
 356         int                     stopping;      /* true if shutting down */
 357
 358         atomic64_t              quotarealms_count; /* # realms with quota */
 359         /*
 360          * We keep a list of inodes we don't see in the mountpoint but that we
 361          * need to track quota realms.
 362          */
 363         struct rb_root          quotarealms_inodes;
 364         struct mutex            quotarealms_inodes_mutex;
 365
 366         /*
 367          * snap_rwsem will cover cap linkage into snaprealms, and
 368          * realm snap contexts.  (later, we can do per-realm snap
 369          * contexts locks..)  the empty list contains realms with no
 370          * references (implying they contain no inodes with caps) that
 371          * should be destroyed.
 372          */
 373         u64                     last_snap_seq;
 374         struct rw_semaphore     snap_rwsem;
 375         struct rb_root          snap_realms;
 376         struct list_head        snap_empty;
 377         int                     num_snap_realms;
 378         spinlock_t              snap_empty_lock;  /* protect snap_empty */
 379
 380         u64                    last_tid;      /* most recent mds request */
 381         u64                    oldest_tid;    /* oldest incomplete mds request,
 382                                                  excluding setfilelock requests */
 383         struct rb_root         request_tree;  /* pending mds requests */
 384         struct delayed_work    delayed_work;  /* delayed work */
 385         unsigned long    last_renew_caps;  /* last time we renewed our caps */
 386         struct list_head cap_delay_list;   /* caps with delayed release */
 387         spinlock_t       cap_delay_lock;   /* protects cap_delay_list */
 388         struct list_head snap_flush_list;  /* cap_snaps ready to flush */
 389         spinlock_t       snap_flush_lock;
 390
 391         u64               last_cap_flush_tid;
 392         struct list_head  cap_flush_list;
 393         struct list_head  cap_dirty;        /* inodes with dirty caps */
 394         struct list_head  cap_dirty_migrating; /* ...that are migration... */
 395         int               num_cap_flushing; /* # caps we are flushing */
 396         spinlock_t        cap_dirty_lock;   /* protects above items */
 397         wait_queue_head_t cap_flushing_wq;
 398
 399         struct work_struct cap_reclaim_work;
 400         atomic_t           cap_reclaim_pending;
 401
 402         /*
 403          * Cap reservations
 404          *
 405          * Maintain a global pool of preallocated struct ceph_caps, referenced
 406          * by struct ceph_caps_reservations.  This ensures that we preallocate
 407          * memory needed to successfully process an MDS response.  (If an MDS
 408          * sends us cap information and we fail to process it, we will have
 409          * problems due to the client and MDS being out of sync.)
 410          *
 411          * Reservations are 'owned' by a ceph_cap_reservation context.
 412          */
 413         spinlock_t      caps_list_lock;
 414         struct          list_head caps_list; /* unused (reserved or
 415                                                 unreserved) */
 416         int             caps_total_count;    /* total caps allocated */
 417         int             caps_use_count;      /* in use */
 418         int             caps_use_max;        /* max used caps */
 419         int             caps_reserve_count;  /* unused, reserved */
 420         int             caps_avail_count;    /* unused, unreserved */
 421         int             caps_min_count;      /* keep at least this many
 422                                                 (unreserved) */
 423         spinlock_t        dentry_list_lock;
 424         struct list_head  dentry_leases;     /* fifo list */
 425         struct list_head  dentry_dir_leases; /* lru list */
 426
 427         spinlock_t              snapid_map_lock;
 428         struct rb_root          snapid_map_tree;
 429         struct list_head        snapid_map_lru;
 430
 431         struct rw_semaphore     pool_perm_rwsem;
 432         struct rb_root          pool_perm_tree;
 433
 434         char nodename[__NEW_UTS_LEN + 1];
 435 };
 436
 437 extern const char *ceph_mds_op_name(int op);
 438
 439 extern struct ceph_mds_session *
 440 __ceph_lookup_mds_session(struct ceph_mds_client *, int mds);
 441
 442 static inline struct ceph_mds_session *
 443 ceph_get_mds_session(struct ceph_mds_session *s)
 444 {
 445         refcount_inc(&s->s_ref);
 446         return s;
 447 }
 448
 449 extern const char *ceph_session_state_name(int s);
 450
 451 extern void ceph_put_mds_session(struct ceph_mds_session *s);
 452
 453 extern int ceph_send_msg_mds(struct ceph_mds_client *mdsc,
 454                              struct ceph_msg *msg, int mds);
 455
 456 extern int ceph_mdsc_init(struct ceph_fs_client *fsc);
 457 extern void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc);
 458 extern void ceph_mdsc_force_umount(struct ceph_mds_client *mdsc);
 459 extern void ceph_mdsc_destroy(struct ceph_fs_client *fsc);
 460
 461 extern void ceph_mdsc_sync(struct ceph_mds_client *mdsc);
 462
 463 extern void ceph_invalidate_dir_request(struct ceph_mds_request *req);
 464 extern int ceph_alloc_readdir_reply_buffer(struct ceph_mds_request *req,
 465                                            struct inode *dir);
 466 extern struct ceph_mds_request *
 467 ceph_mdsc_create_request(struct ceph_mds_client *mdsc, int op, int mode);
 468 extern int ceph_mdsc_submit_request(struct ceph_mds_client *mdsc,
 469                                     struct inode *dir,
 470                                     struct ceph_mds_request *req);
 471 extern int ceph_mdsc_do_request(struct ceph_mds_client *mdsc,
 472                                 struct inode *dir,
 473                                 struct ceph_mds_request *req);
 474 static inline void ceph_mdsc_get_request(struct ceph_mds_request *req)
 475 {
 476         kref_get(&req->r_kref);
 477 }
 478 extern void ceph_mdsc_release_request(struct kref *kref);
 479 static inline void ceph_mdsc_put_request(struct ceph_mds_request *req)
 480 {
 481         kref_put(&req->r_kref, ceph_mdsc_release_request);
 482 }
 483
 484 extern void __ceph_queue_cap_release(struct ceph_mds_session *session,
 485                                     struct ceph_cap *cap);
 486 extern void ceph_flush_cap_releases(struct ceph_mds_client *mdsc,
 487                                     struct ceph_mds_session *session);
 488 extern void ceph_queue_cap_reclaim_work(struct ceph_mds_client *mdsc);
 489 extern void ceph_reclaim_caps_nr(struct ceph_mds_client *mdsc, int nr);
 490 extern int ceph_iterate_session_caps(struct ceph_mds_session *session,
 491                                      int (*cb)(struct inode *,
 492                                                struct ceph_cap *, void *),
 493                                      void *arg);
 494 extern void ceph_mdsc_pre_umount(struct ceph_mds_client *mdsc);
 495
 496 static inline void ceph_mdsc_free_path(char *path, int len)
 497 {
 498         if (path)
 499                 __putname(path - (PATH_MAX - 1 - len));
 500 }
 501
 502 extern char *ceph_mdsc_build_path(struct dentry *dentry, int *plen, u64 *base,
 503                                   int stop_on_nosnap);
 504
 505 extern void __ceph_mdsc_drop_dentry_lease(struct dentry *dentry);
 506 extern void ceph_mdsc_lease_send_msg(struct ceph_mds_session *session,
 507                                      struct inode *inode,
 508                                      struct dentry *dentry, char action,
 509                                      u32 seq);
 510
 511 extern void ceph_mdsc_handle_mdsmap(struct ceph_mds_client *mdsc,
 512                                     struct ceph_msg *msg);
 513 extern void ceph_mdsc_handle_fsmap(struct ceph_mds_client *mdsc,
 514                                    struct ceph_msg *msg);
 515
 516 extern struct ceph_mds_session *
 517 ceph_mdsc_open_export_target_session(struct ceph_mds_client *mdsc, int target);
 518 extern void ceph_mdsc_open_export_target_sessions(struct ceph_mds_client *mdsc,
 519                                           struct ceph_mds_session *session);
 520
 521 extern int ceph_trim_caps(struct ceph_mds_client *mdsc,
 522                           struct ceph_mds_session *session,
 523                           int max_caps);
 524 #endif