fs/ceph/super.h

   1 #ifndef _FS_CEPH_SUPER_H
   2 #define _FS_CEPH_SUPER_H
   3
   4 #include "ceph_debug.h"
   5
   6 #include <asm/unaligned.h>
   7 #include <linux/backing-dev.h>
   8 #include <linux/completion.h>
   9 #include <linux/exportfs.h>
  10 #include <linux/fs.h>
  11 #include <linux/mempool.h>
  12 #include <linux/pagemap.h>
  13 #include <linux/wait.h>
  14 #include <linux/writeback.h>
  15
  16 #include "types.h"
  17 #include "messenger.h"
  18 #include "msgpool.h"
  19 #include "mon_client.h"
  20 #include "mds_client.h"
  21 #include "osd_client.h"
  22 #include "ceph_fs.h"
  23
  24 /* f_type in struct statfs */
  25 #define CEPH_SUPER_MAGIC 0x00c36400
  26
  27 /* large granularity for statfs utilization stats to facilitate
  28  * large volume sizes on 32-bit machines. */
  29 #define CEPH_BLOCK_SHIFT   20  /* 1 MB */
  30 #define CEPH_BLOCK         (1 << CEPH_BLOCK_SHIFT)
  31
  32 /*
  33  * mount options
  34  */
  35 #define CEPH_OPT_FSID             (1<<0)
  36 #define CEPH_OPT_NOSHARE          (1<<1) /* don't share client with other sbs */
  37 #define CEPH_OPT_MYIP             (1<<2) /* specified my ip */
  38 #define CEPH_OPT_DIRSTAT          (1<<4) /* funky `cat dirname` for stats */
  39 #define CEPH_OPT_RBYTES           (1<<5) /* dir st_bytes = rbytes */
  40 #define CEPH_OPT_NOCRC            (1<<6) /* no data crc on writes */
  41 #define CEPH_OPT_NOASYNCREADDIR   (1<<7) /* no dcache readdir */
  42
  43 #define CEPH_OPT_DEFAULT   (CEPH_OPT_RBYTES)
  44
  45 #define ceph_set_opt(client, opt) \
  46         (client)->mount_args->flags |= CEPH_OPT_##opt;
  47 #define ceph_test_opt(client, opt) \
  48         (!!((client)->mount_args->flags & CEPH_OPT_##opt))
  49
  50
  51 struct ceph_mount_args {
  52         int sb_flags;
  53         int num_mon;
  54         struct ceph_entity_addr *mon_addr;
  55         int flags;
  56         int mount_timeout;
  57         int osd_idle_ttl;
  58         int caps_wanted_delay_min, caps_wanted_delay_max;
  59         struct ceph_fsid fsid;
  60         struct ceph_entity_addr my_addr;
  61         int wsize;
  62         int rsize;            /* max readahead */
  63         int max_readdir;      /* max readdir size */
  64         int congestion_kb;      /* max readdir size */
  65         int osd_timeout;
  66         int osd_keepalive_timeout;
  67         char *snapdir_name;   /* default ".snap" */
  68         char *name;
  69         char *secret;
  70         int cap_release_safety;
  71 };
  72
  73 /*
  74  * defaults
  75  */
  76 #define CEPH_MOUNT_TIMEOUT_DEFAULT  60
  77 #define CEPH_OSD_TIMEOUT_DEFAULT    60  /* seconds */
  78 #define CEPH_OSD_KEEPALIVE_DEFAULT  5
  79 #define CEPH_OSD_IDLE_TTL_DEFAULT    60
  80 #define CEPH_MOUNT_RSIZE_DEFAULT    (512*1024) /* readahead */
  81
  82 #define CEPH_MSG_MAX_FRONT_LEN  (16*1024*1024)
  83 #define CEPH_MSG_MAX_DATA_LEN   (16*1024*1024)
  84
  85 #define CEPH_SNAPDIRNAME_DEFAULT ".snap"
  86 #define CEPH_AUTH_NAME_DEFAULT   "guest"
  87
  88 /*
  89  * Delay telling the MDS we no longer want caps, in case we reopen
  90  * the file.  Delay a minimum amount of time, even if we send a cap
  91  * message for some other reason.  Otherwise, take the oppotunity to
  92  * update the mds to avoid sending another message later.
  93  */
  94 #define CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT      5  /* cap release delay */
  95 #define CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT     60  /* cap release delay */
  96
  97
  98 /* mount state */
  99 enum {
 100         CEPH_MOUNT_MOUNTING,
 101         CEPH_MOUNT_MOUNTED,
 102         CEPH_MOUNT_UNMOUNTING,
 103         CEPH_MOUNT_UNMOUNTED,
 104         CEPH_MOUNT_SHUTDOWN,
 105 };
 106
 107 /*
 108  * subtract jiffies
 109  */
 110 static inline unsigned long time_sub(unsigned long a, unsigned long b)
 111 {
 112         BUG_ON(time_after(b, a));
 113         return (long)a - (long)b;
 114 }
 115
 116 /*
 117  * per-filesystem client state
 118  *
 119  * possibly shared by multiple mount points, if they are
 120  * mounting the same ceph filesystem/cluster.
 121  */
 122 struct ceph_client {
 123         struct ceph_fsid fsid;
 124         bool have_fsid;
 125
 126         struct mutex mount_mutex;       /* serialize mount attempts */
 127         struct ceph_mount_args *mount_args;
 128
 129         struct super_block *sb;
 130
 131         unsigned long mount_state;
 132         wait_queue_head_t auth_wq;
 133
 134         int auth_err;
 135
 136         int min_caps;                  /* min caps i added */
 137
 138         struct ceph_messenger *msgr;   /* messenger instance */
 139         struct ceph_mon_client monc;
 140         struct ceph_mds_client mdsc;
 141         struct ceph_osd_client osdc;
 142
 143         /* writeback */
 144         mempool_t *wb_pagevec_pool;
 145         struct workqueue_struct *wb_wq;
 146         struct workqueue_struct *pg_inv_wq;
 147         struct workqueue_struct *trunc_wq;
 148         atomic_long_t writeback_count;
 149
 150         struct backing_dev_info backing_dev_info;
 151
 152 #ifdef CONFIG_DEBUG_FS
 153         struct dentry *debugfs_monmap;
 154         struct dentry *debugfs_mdsmap, *debugfs_osdmap;
 155         struct dentry *debugfs_dir, *debugfs_dentry_lru, *debugfs_caps;
 156         struct dentry *debugfs_congestion_kb;
 157         struct dentry *debugfs_bdi;
 158 #endif
 159 };
 160
 161 static inline struct ceph_client *ceph_client(struct super_block *sb)
 162 {
 163         return sb->s_fs_info;
 164 }
 165
 166
 167 /*
 168  * File i/o capability.  This tracks shared state with the metadata
 169  * server that allows us to cache or writeback attributes or to read
 170  * and write data.  For any given inode, we should have one or more
 171  * capabilities, one issued by each metadata server, and our
 172  * cumulative access is the OR of all issued capabilities.
 173  *
 174  * Each cap is referenced by the inode's i_caps rbtree and by per-mds
 175  * session capability lists.
 176  */
 177 struct ceph_cap {
 178         struct ceph_inode_info *ci;
 179         struct rb_node ci_node;          /* per-ci cap tree */
 180         struct ceph_mds_session *session;
 181         struct list_head session_caps;   /* per-session caplist */
 182         int mds;
 183         u64 cap_id;       /* unique cap id (mds provided) */
 184         int issued;       /* latest, from the mds */
 185         int implemented;  /* implemented superset of issued (for revocation) */
 186         int mds_wanted;
 187         u32 seq, issue_seq, mseq;
 188         u32 cap_gen;      /* active/stale cycle */
 189         unsigned long last_used;
 190         struct list_head caps_item;
 191 };
 192
 193 #define CHECK_CAPS_NODELAY    1  /* do not delay any further */
 194 #define CHECK_CAPS_AUTHONLY   2  /* only check auth cap */
 195 #define CHECK_CAPS_FLUSH      4  /* flush any dirty caps */
 196
 197 /*
 198  * Snapped cap state that is pending flush to mds.  When a snapshot occurs,
 199  * we first complete any in-process sync writes and writeback any dirty
 200  * data before flushing the snapped state (tracked here) back to the MDS.
 201  */
 202 struct ceph_cap_snap {
 203         atomic_t nref;
 204         struct ceph_inode_info *ci;
 205         struct list_head ci_item, flushing_item;
 206
 207         u64 follows, flush_tid;
 208         int issued, dirty;
 209         struct ceph_snap_context *context;
 210
 211         mode_t mode;
 212         uid_t uid;
 213         gid_t gid;
 214
 215         void *xattr_blob;
 216         int xattr_len;
 217         u64 xattr_version;
 218
 219         u64 size;
 220         struct timespec mtime, atime, ctime;
 221         u64 time_warp_seq;
 222         int writing;   /* a sync write is still in progress */
 223         int dirty_pages;     /* dirty pages awaiting writeback */
 224 };
 225
 226 static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap)
 227 {
 228         if (atomic_dec_and_test(&capsnap->nref))
 229                 kfree(capsnap);
 230 }
 231
 232 /*
 233  * The frag tree describes how a directory is fragmented, potentially across
 234  * multiple metadata servers.  It is also used to indicate points where
 235  * metadata authority is delegated, and whether/where metadata is replicated.
 236  *
 237  * A _leaf_ frag will be present in the i_fragtree IFF there is
 238  * delegation info.  That is, if mds >= 0 || ndist > 0.
 239  */
 240 #define CEPH_MAX_DIRFRAG_REP 4
 241
 242 struct ceph_inode_frag {
 243         struct rb_node node;
 244
 245         /* fragtree state */
 246         u32 frag;
 247         int split_by;         /* i.e. 2^(split_by) children */
 248
 249         /* delegation and replication info */
 250         int mds;              /* -1 if same authority as parent */
 251         int ndist;            /* >0 if replicated */
 252         int dist[CEPH_MAX_DIRFRAG_REP];
 253 };
 254
 255 /*
 256  * We cache inode xattrs as an encoded blob until they are first used,
 257  * at which point we parse them into an rbtree.
 258  */
 259 struct ceph_inode_xattr {
 260         struct rb_node node;
 261
 262         const char *name;
 263         int name_len;
 264         const char *val;
 265         int val_len;
 266         int dirty;
 267
 268         int should_free_name;
 269         int should_free_val;
 270 };
 271
 272 struct ceph_inode_xattrs_info {
 273         /*
 274          * (still encoded) xattr blob. we avoid the overhead of parsing
 275          * this until someone actually calls getxattr, etc.
 276          *
 277          * blob->vec.iov_len == 4 implies there are no xattrs; blob ==
 278          * NULL means we don't know.
 279         */
 280         struct ceph_buffer *blob, *prealloc_blob;
 281
 282         struct rb_root index;
 283         bool dirty;
 284         int count;
 285         int names_size;
 286         int vals_size;
 287         u64 version, index_version;
 288 };
 289
 290 /*
 291  * Ceph inode.
 292  */
 293 #define CEPH_I_COMPLETE  1  /* we have complete directory cached */
 294 #define CEPH_I_NODELAY   4  /* do not delay cap release */
 295 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
 296 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
 297
 298 struct ceph_inode_info {
 299         struct ceph_vino i_vino;   /* ceph ino + snap */
 300
 301         u64 i_version;
 302         u32 i_time_warp_seq;
 303
 304         unsigned i_ceph_flags;
 305         unsigned long i_release_count;
 306
 307         struct ceph_file_layout i_layout;
 308         char *i_symlink;
 309
 310         /* for dirs */
 311         struct timespec i_rctime;
 312         u64 i_rbytes, i_rfiles, i_rsubdirs;
 313         u64 i_files, i_subdirs;
 314         u64 i_max_offset;  /* largest readdir offset, set with I_COMPLETE */
 315
 316         struct rb_root i_fragtree;
 317         struct mutex i_fragtree_mutex;
 318
 319         struct ceph_inode_xattrs_info i_xattrs;
 320
 321         /* capabilities.  protected _both_ by i_lock and cap->session's
 322          * s_mutex. */
 323         struct rb_root i_caps;           /* cap list */
 324         struct ceph_cap *i_auth_cap;     /* authoritative cap, if any */
 325         unsigned i_dirty_caps, i_flushing_caps;     /* mask of dirtied fields */
 326         struct list_head i_dirty_item, i_flushing_item;
 327         u64 i_cap_flush_seq;
 328         /* we need to track cap writeback on a per-cap-bit basis, to allow
 329          * overlapping, pipelined cap flushes to the mds.  we can probably
 330          * reduce the tid to 8 bits if we're concerned about inode size. */
 331         u16 i_cap_flush_last_tid, i_cap_flush_tid[CEPH_CAP_BITS];
 332         wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
 333         unsigned long i_hold_caps_min; /* jiffies */
 334         unsigned long i_hold_caps_max; /* jiffies */
 335         struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
 336         int i_cap_exporting_mds;         /* to handle cap migration between */
 337         unsigned i_cap_exporting_mseq;   /*  mds's. */
 338         unsigned i_cap_exporting_issued;
 339         struct ceph_cap_reservation i_cap_migration_resv;
 340         struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
 341         struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 */
 342         unsigned i_snap_caps;           /* cap bits for snapped files */
 343
 344         int i_nr_by_mode[CEPH_FILE_MODE_NUM];  /* open file counts */
 345
 346         u32 i_truncate_seq;        /* last truncate to smaller size */
 347         u64 i_truncate_size;       /*  and the size we last truncated down to */
 348         int i_truncate_pending;    /*  still need to call vmtruncate */
 349
 350         u64 i_max_size;            /* max file size authorized by mds */
 351         u64 i_reported_size; /* (max_)size reported to or requested of mds */
 352         u64 i_wanted_max_size;     /* offset we'd like to write too */
 353         u64 i_requested_max_size;  /* max_size we've requested */
 354
 355         /* held references to caps */
 356         int i_pin_ref;
 357         int i_rd_ref, i_rdcache_ref, i_wr_ref;
 358         int i_wrbuffer_ref, i_wrbuffer_ref_head;
 359         u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
 360         u32 i_rdcache_gen;      /* we increment this each time we get
 361                                    FILE_CACHE.  If it's non-zero, we
 362                                    _may_ have cached pages. */
 363         u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
 364
 365         struct list_head i_unsafe_writes; /* uncommitted sync writes */
 366         struct list_head i_unsafe_dirops; /* uncommitted mds dir ops */
 367         spinlock_t i_unsafe_lock;
 368
 369         struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
 370         int i_snap_realm_counter; /* snap realm (if caps) */
 371         struct list_head i_snap_realm_item;
 372         struct list_head i_snap_flush_item;
 373
 374         struct work_struct i_wb_work;  /* writeback work */
 375         struct work_struct i_pg_inv_work;  /* page invalidation work */
 376
 377         struct work_struct i_vmtruncate_work;
 378
 379         struct inode vfs_inode; /* at end */
 380 };
 381
 382 static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
 383 {
 384         return container_of(inode, struct ceph_inode_info, vfs_inode);
 385 }
 386
 387 static inline void ceph_i_clear(struct inode *inode, unsigned mask)
 388 {
 389         struct ceph_inode_info *ci = ceph_inode(inode);
 390
 391         spin_lock(&inode->i_lock);
 392         ci->i_ceph_flags &= ~mask;
 393         spin_unlock(&inode->i_lock);
 394 }
 395
 396 static inline void ceph_i_set(struct inode *inode, unsigned mask)
 397 {
 398         struct ceph_inode_info *ci = ceph_inode(inode);
 399
 400         spin_lock(&inode->i_lock);
 401         ci->i_ceph_flags |= mask;
 402         spin_unlock(&inode->i_lock);
 403 }
 404
 405 static inline bool ceph_i_test(struct inode *inode, unsigned mask)
 406 {
 407         struct ceph_inode_info *ci = ceph_inode(inode);
 408         bool r;
 409
 410         smp_mb();
 411         r = (ci->i_ceph_flags & mask) == mask;
 412         return r;
 413 }
 414
 415
 416 /* find a specific frag @f */
 417 extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
 418                                                 u32 f);
 419
 420 /*
 421  * choose fragment for value @v.  copy frag content to pfrag, if leaf
 422  * exists
 423  */
 424 extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
 425                             struct ceph_inode_frag *pfrag,
 426                             int *found);
 427
 428 /*
 429  * Ceph dentry state
 430  */
 431 struct ceph_dentry_info {
 432         struct ceph_mds_session *lease_session;
 433         u32 lease_gen, lease_shared_gen;
 434         u32 lease_seq;
 435         unsigned long lease_renew_after, lease_renew_from;
 436         struct list_head lru;
 437         struct dentry *dentry;
 438         u64 time;
 439         u64 offset;
 440 };
 441
 442 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
 443 {
 444         return (struct ceph_dentry_info *)dentry->d_fsdata;
 445 }
 446
 447 static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
 448 {
 449         return ((loff_t)frag << 32) | (loff_t)off;
 450 }
 451
 452 /*
 453  * ino_t is <64 bits on many architectures, blech.
 454  *
 455  * don't include snap in ino hash, at least for now.
 456  */
 457 static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
 458 {
 459         ino_t ino = (ino_t)vino.ino;  /* ^ (vino.snap << 20); */
 460 #if BITS_PER_LONG == 32
 461         ino ^= vino.ino >> (sizeof(u64)-sizeof(ino_t)) * 8;
 462         if (!ino)
 463                 ino = 1;
 464 #endif
 465         return ino;
 466 }
 467
 468 static inline int ceph_set_ino_cb(struct inode *inode, void *data)
 469 {
 470         ceph_inode(inode)->i_vino = *(struct ceph_vino *)data;
 471         inode->i_ino = ceph_vino_to_ino(*(struct ceph_vino *)data);
 472         return 0;
 473 }
 474
 475 static inline struct ceph_vino ceph_vino(struct inode *inode)
 476 {
 477         return ceph_inode(inode)->i_vino;
 478 }
 479
 480 /* for printf-style formatting */
 481 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
 482
 483 static inline u64 ceph_ino(struct inode *inode)
 484 {
 485         return ceph_inode(inode)->i_vino.ino;
 486 }
 487 static inline u64 ceph_snap(struct inode *inode)
 488 {
 489         return ceph_inode(inode)->i_vino.snap;
 490 }
 491
 492 static inline int ceph_ino_compare(struct inode *inode, void *data)
 493 {
 494         struct ceph_vino *pvino = (struct ceph_vino *)data;
 495         struct ceph_inode_info *ci = ceph_inode(inode);
 496         return ci->i_vino.ino == pvino->ino &&
 497                 ci->i_vino.snap == pvino->snap;
 498 }
 499
 500 static inline struct inode *ceph_find_inode(struct super_block *sb,
 501                                             struct ceph_vino vino)
 502 {
 503         ino_t t = ceph_vino_to_ino(vino);
 504         return ilookup5(sb, t, ceph_ino_compare, &vino);
 505 }
 506
 507
 508 /*
 509  * caps helpers
 510  */
 511 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
 512 {
 513         return !RB_EMPTY_ROOT(&ci->i_caps);
 514 }
 515
 516 extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented);
 517 extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t);
 518 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
 519                                     struct ceph_cap *cap);
 520
 521 static inline int ceph_caps_issued(struct ceph_inode_info *ci)
 522 {
 523         int issued;
 524         spin_lock(&ci->vfs_inode.i_lock);
 525         issued = __ceph_caps_issued(ci, NULL);
 526         spin_unlock(&ci->vfs_inode.i_lock);
 527         return issued;
 528 }
 529
 530 static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
 531                                         int touch)
 532 {
 533         int r;
 534         spin_lock(&ci->vfs_inode.i_lock);
 535         r = __ceph_caps_issued_mask(ci, mask, touch);
 536         spin_unlock(&ci->vfs_inode.i_lock);
 537         return r;
 538 }
 539
 540 static inline int __ceph_caps_dirty(struct ceph_inode_info *ci)
 541 {
 542         return ci->i_dirty_caps | ci->i_flushing_caps;
 543 }
 544 extern void __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask);
 545
 546 extern int ceph_caps_revoking(struct ceph_inode_info *ci, int mask);
 547 extern int __ceph_caps_used(struct ceph_inode_info *ci);
 548
 549 extern int __ceph_caps_file_wanted(struct ceph_inode_info *ci);
 550
 551 /*
 552  * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
 553  */
 554 static inline int __ceph_caps_wanted(struct ceph_inode_info *ci)
 555 {
 556         int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
 557         if (w & CEPH_CAP_FILE_BUFFER)
 558                 w |= CEPH_CAP_FILE_EXCL;  /* we want EXCL if dirty data */
 559         return w;
 560 }
 561
 562 /* what the mds thinks we want */
 563 extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci);
 564
 565 extern void ceph_caps_init(void);
 566 extern void ceph_caps_finalize(void);
 567 extern void ceph_adjust_min_caps(int delta);
 568 extern int ceph_reserve_caps(struct ceph_cap_reservation *ctx, int need);
 569 extern int ceph_unreserve_caps(struct ceph_cap_reservation *ctx);
 570 extern void ceph_reservation_status(struct ceph_client *client,
 571                                     int *total, int *avail, int *used,
 572                                     int *reserved, int *min);
 573
 574 static inline struct ceph_client *ceph_inode_to_client(struct inode *inode)
 575 {
 576         return (struct ceph_client *)inode->i_sb->s_fs_info;
 577 }
 578
 579 static inline struct ceph_client *ceph_sb_to_client(struct super_block *sb)
 580 {
 581         return (struct ceph_client *)sb->s_fs_info;
 582 }
 583
 584
 585 /*
 586  * we keep buffered readdir results attached to file->private_data
 587  */
 588 struct ceph_file_info {
 589         int fmode;     /* initialized on open */
 590
 591         /* readdir: position within the dir */
 592         u32 frag;
 593         struct ceph_mds_request *last_readdir;
 594         int at_end;
 595
 596         /* readdir: position within a frag */
 597         unsigned offset;       /* offset of last chunk, adjusted for . and .. */
 598         u64 next_offset;       /* offset of next chunk (last_name's + 1) */
 599         char *last_name;       /* last entry in previous chunk */
 600         struct dentry *dentry; /* next dentry (for dcache readdir) */
 601         unsigned long dir_release_count;
 602
 603         /* used for -o dirstat read() on directory thing */
 604         char *dir_info;
 605         int dir_info_len;
 606 };
 607
 608
 609
 610 /*
 611  * snapshots
 612  */
 613
 614 /*
 615  * A "snap context" is the set of existing snapshots when we
 616  * write data.  It is used by the OSD to guide its COW behavior.
 617  *
 618  * The ceph_snap_context is refcounted, and attached to each dirty
 619  * page, indicating which context the dirty data belonged when it was
 620  * dirtied.
 621  */
 622 struct ceph_snap_context {
 623         atomic_t nref;
 624         u64 seq;
 625         int num_snaps;
 626         u64 snaps[];
 627 };
 628
 629 static inline struct ceph_snap_context *
 630 ceph_get_snap_context(struct ceph_snap_context *sc)
 631 {
 632         /*
 633         printk("get_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 634                atomic_read(&sc->nref)+1);
 635         */
 636         if (sc)
 637                 atomic_inc(&sc->nref);
 638         return sc;
 639 }
 640
 641 static inline void ceph_put_snap_context(struct ceph_snap_context *sc)
 642 {
 643         if (!sc)
 644                 return;
 645         /*
 646         printk("put_snap_context %p %d -> %d\n", sc, atomic_read(&sc->nref),
 647                atomic_read(&sc->nref)-1);
 648         */
 649         if (atomic_dec_and_test(&sc->nref)) {
 650                 /*printk(" deleting snap_context %p\n", sc);*/
 651                 kfree(sc);
 652         }
 653 }
 654
 655 /*
 656  * A "snap realm" describes a subset of the file hierarchy sharing
 657  * the same set of snapshots that apply to it.  The realms themselves
 658  * are organized into a hierarchy, such that children inherit (some of)
 659  * the snapshots of their parents.
 660  *
 661  * All inodes within the realm that have capabilities are linked into a
 662  * per-realm list.
 663  */
 664 struct ceph_snap_realm {
 665         u64 ino;
 666         atomic_t nref;
 667         struct rb_node node;
 668
 669         u64 created, seq;
 670         u64 parent_ino;
 671         u64 parent_since;   /* snapid when our current parent became so */
 672
 673         u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
 674         int num_prior_parent_snaps;   /*  had prior to parent_since */
 675         u64 *snaps;                   /* snaps specific to this realm */
 676         int num_snaps;
 677
 678         struct ceph_snap_realm *parent;
 679         struct list_head children;       /* list of child realms */
 680         struct list_head child_item;
 681
 682         struct list_head empty_item;     /* if i have ref==0 */
 683
 684         /* the current set of snaps for this realm */
 685         struct ceph_snap_context *cached_context;
 686
 687         struct list_head inodes_with_caps;
 688         spinlock_t inodes_with_caps_lock;
 689 };
 690
 691
 692
 693 /*
 694  * calculate the number of pages a given length and offset map onto,
 695  * if we align the data.
 696  */
 697 static inline int calc_pages_for(u64 off, u64 len)
 698 {
 699         return ((off+len+PAGE_CACHE_SIZE-1) >> PAGE_CACHE_SHIFT) -
 700                 (off >> PAGE_CACHE_SHIFT);
 701 }
 702
 703
 704
 705 /* snap.c */
 706 struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
 707                                                u64 ino);
 708 extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
 709                                 struct ceph_snap_realm *realm);
 710 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
 711                                 struct ceph_snap_realm *realm);
 712 extern int ceph_update_snap_trace(struct ceph_mds_client *m,
 713                                   void *p, void *e, bool deletion);
 714 extern void ceph_handle_snap(struct ceph_mds_client *mdsc,
 715                              struct ceph_mds_session *session,
 716                              struct ceph_msg *msg);
 717 extern void ceph_queue_cap_snap(struct ceph_inode_info *ci,
 718                                 struct ceph_snap_context *snapc);
 719 extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
 720                                   struct ceph_cap_snap *capsnap);
 721 extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc);
 722
 723 /*
 724  * a cap_snap is "pending" if it is still awaiting an in-progress
 725  * sync write (that may/may not still update size, mtime, etc.).
 726  */
 727 static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
 728 {
 729         return !list_empty(&ci->i_cap_snaps) &&
 730                 list_entry(ci->i_cap_snaps.prev, struct ceph_cap_snap,
 731                            ci_item)->writing;
 732 }
 733
 734
 735 /* super.c */
 736 extern struct kmem_cache *ceph_inode_cachep;
 737 extern struct kmem_cache *ceph_cap_cachep;
 738 extern struct kmem_cache *ceph_dentry_cachep;
 739 extern struct kmem_cache *ceph_file_cachep;
 740
 741 extern const char *ceph_msg_type_name(int type);
 742 extern int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid);
 743
 744 #define FSID_FORMAT "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-" \
 745         "%02x%02x%02x%02x%02x%02x"
 746 #define PR_FSID(f) (f)->fsid[0], (f)->fsid[1], (f)->fsid[2], (f)->fsid[3], \
 747                 (f)->fsid[4], (f)->fsid[5], (f)->fsid[6], (f)->fsid[7],    \
 748                 (f)->fsid[8], (f)->fsid[9], (f)->fsid[10], (f)->fsid[11],  \
 749                 (f)->fsid[12], (f)->fsid[13], (f)->fsid[14], (f)->fsid[15]
 750
 751 /* inode.c */
 752 extern const struct inode_operations ceph_file_iops;
 753
 754 extern struct inode *ceph_alloc_inode(struct super_block *sb);
 755 extern void ceph_destroy_inode(struct inode *inode);
 756
 757 extern struct inode *ceph_get_inode(struct super_block *sb,
 758                                     struct ceph_vino vino);
 759 extern struct inode *ceph_get_snapdir(struct inode *parent);
 760 extern int ceph_fill_file_size(struct inode *inode, int issued,
 761                                u32 truncate_seq, u64 truncate_size, u64 size);
 762 extern void ceph_fill_file_time(struct inode *inode, int issued,
 763                                 u64 time_warp_seq, struct timespec *ctime,
 764                                 struct timespec *mtime, struct timespec *atime);
 765 extern int ceph_fill_trace(struct super_block *sb,
 766                            struct ceph_mds_request *req,
 767                            struct ceph_mds_session *session);
 768 extern int ceph_readdir_prepopulate(struct ceph_mds_request *req,
 769                                     struct ceph_mds_session *session);
 770
 771 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
 772
 773 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
 774 extern void __ceph_do_pending_vmtruncate(struct inode *inode);
 775 extern void ceph_queue_vmtruncate(struct inode *inode);
 776
 777 extern void ceph_queue_invalidate(struct inode *inode);
 778 extern void ceph_queue_writeback(struct inode *inode);
 779
 780 extern int ceph_do_getattr(struct inode *inode, int mask);
 781 extern int ceph_permission(struct inode *inode, int mask);
 782 extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
 783 extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
 784                         struct kstat *stat);
 785
 786 /* xattr.c */
 787 extern int ceph_setxattr(struct dentry *, const char *, const void *,
 788                          size_t, int);
 789 extern ssize_t ceph_getxattr(struct dentry *, const char *, void *, size_t);
 790 extern ssize_t ceph_listxattr(struct dentry *, char *, size_t);
 791 extern int ceph_removexattr(struct dentry *, const char *);
 792 extern void __ceph_build_xattrs_blob(struct ceph_inode_info *ci);
 793 extern void __ceph_destroy_xattrs(struct ceph_inode_info *ci);
 794
 795 /* caps.c */
 796 extern const char *ceph_cap_string(int c);
 797 extern void ceph_handle_caps(struct ceph_mds_session *session,
 798                              struct ceph_msg *msg);
 799 extern int ceph_add_cap(struct inode *inode,
 800                         struct ceph_mds_session *session, u64 cap_id,
 801                         int fmode, unsigned issued, unsigned wanted,
 802                         unsigned cap, unsigned seq, u64 realmino, int flags,
 803                         struct ceph_cap_reservation *caps_reservation);
 804 extern void __ceph_remove_cap(struct ceph_cap *cap);
 805 static inline void ceph_remove_cap(struct ceph_cap *cap)
 806 {
 807         struct inode *inode = &cap->ci->vfs_inode;
 808         spin_lock(&inode->i_lock);
 809         __ceph_remove_cap(cap);
 810         spin_unlock(&inode->i_lock);
 811 }
 812 extern void ceph_put_cap(struct ceph_cap *cap);
 813
 814 extern void ceph_queue_caps_release(struct inode *inode);
 815 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
 816 extern int ceph_fsync(struct file *file, struct dentry *dentry, int datasync);
 817 extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
 818                                     struct ceph_mds_session *session);
 819 extern int ceph_get_cap_mds(struct inode *inode);
 820 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
 821 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
 822 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
 823                                        struct ceph_snap_context *snapc);
 824 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
 825                                struct ceph_mds_session **psession);
 826 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 827                             struct ceph_mds_session *session);
 828 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);
 829 extern void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc);
 830
 831 extern int ceph_encode_inode_release(void **p, struct inode *inode,
 832                                      int mds, int drop, int unless, int force);
 833 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
 834                                       int mds, int drop, int unless);
 835
 836 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
 837                          int *got, loff_t endoff);
 838
 839 /* for counting open files by mode */
 840 static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)
 841 {
 842         ci->i_nr_by_mode[mode]++;
 843 }
 844 extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);
 845
 846 /* addr.c */
 847 extern const struct address_space_operations ceph_aops;
 848 extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
 849
 850 /* file.c */
 851 extern const struct file_operations ceph_file_fops;
 852 extern const struct address_space_operations ceph_aops;
 853 extern int ceph_open(struct inode *inode, struct file *file);
 854 extern struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
 855                                        struct nameidata *nd, int mode,
 856                                        int locked_dir);
 857 extern int ceph_release(struct inode *inode, struct file *filp);
 858 extern void ceph_release_page_vector(struct page **pages, int num_pages);
 859
 860 /* dir.c */
 861 extern const struct file_operations ceph_dir_fops;
 862 extern const struct inode_operations ceph_dir_iops;
 863 extern struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
 864         ceph_snapdir_dentry_ops;
 865
 866 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
 867 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 868                                          struct dentry *dentry, int err);
 869
 870 extern void ceph_dentry_lru_add(struct dentry *dn);
 871 extern void ceph_dentry_lru_touch(struct dentry *dn);
 872 extern void ceph_dentry_lru_del(struct dentry *dn);
 873
 874 /*
 875  * our d_ops vary depending on whether the inode is live,
 876  * snapshotted (read-only), or a virtual ".snap" directory.
 877  */
 878 int ceph_init_dentry(struct dentry *dentry);
 879
 880
 881 /* ioctl.c */
 882 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 883
 884 /* export.c */
 885 extern const struct export_operations ceph_export_ops;
 886
 887 /* debugfs.c */
 888 extern int ceph_debugfs_init(void);
 889 extern void ceph_debugfs_cleanup(void);
 890 extern int ceph_debugfs_client_init(struct ceph_client *client);
 891 extern void ceph_debugfs_client_cleanup(struct ceph_client *client);
 892
 893 static inline struct inode *get_dentry_parent_inode(struct dentry *dentry)
 894 {
 895         if (dentry && dentry->d_parent)
 896                 return dentry->d_parent->d_inode;
 897
 898         return NULL;
 899 }
 900
 901 #endif /* _FS_CEPH_SUPER_H */