fs/ceph/super.h

   1 #ifndef _FS_CEPH_SUPER_H
   2 #define _FS_CEPH_SUPER_H
   3
   4 #include <linux/ceph/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 #include <linux/slab.h>
  16
  17 #include <linux/ceph/libceph.h>
  18
  19 /* f_type in struct statfs */
  20 #define CEPH_SUPER_MAGIC 0x00c36400
  21
  22 /* large granularity for statfs utilization stats to facilitate
  23  * large volume sizes on 32-bit machines. */
  24 #define CEPH_BLOCK_SHIFT   20  /* 1 MB */
  25 #define CEPH_BLOCK         (1 << CEPH_BLOCK_SHIFT)
  26
  27 #define CEPH_MOUNT_OPT_DIRSTAT         (1<<4) /* `cat dirname` for stats */
  28 #define CEPH_MOUNT_OPT_RBYTES          (1<<5) /* dir st_bytes = rbytes */
  29 #define CEPH_MOUNT_OPT_NOASYNCREADDIR  (1<<7) /* no dcache readdir */
  30 #define CEPH_MOUNT_OPT_INO32           (1<<8) /* 32 bit inos */
  31 #define CEPH_MOUNT_OPT_DCACHE          (1<<9) /* use dcache for readdir etc */
  32
  33 #define CEPH_MOUNT_OPT_DEFAULT    (CEPH_MOUNT_OPT_RBYTES)
  34
  35 #define ceph_set_mount_opt(fsc, opt) \
  36         (fsc)->mount_options->flags |= CEPH_MOUNT_OPT_##opt;
  37 #define ceph_test_mount_opt(fsc, opt) \
  38         (!!((fsc)->mount_options->flags & CEPH_MOUNT_OPT_##opt))
  39
  40 #define CEPH_RSIZE_DEFAULT             0           /* max read size */
  41 #define CEPH_RASIZE_DEFAULT            (8192*1024) /* readahead */
  42 #define CEPH_MAX_READDIR_DEFAULT        1024
  43 #define CEPH_MAX_READDIR_BYTES_DEFAULT  (512*1024)
  44 #define CEPH_SNAPDIRNAME_DEFAULT        ".snap"
  45
  46 struct ceph_mount_options {
  47         int flags;
  48         int sb_flags;
  49
  50         int wsize;            /* max write size */
  51         int rsize;            /* max read size */
  52         int rasize;           /* max readahead */
  53         int congestion_kb;    /* max writeback in flight */
  54         int caps_wanted_delay_min, caps_wanted_delay_max;
  55         int cap_release_safety;
  56         int max_readdir;       /* max readdir result (entires) */
  57         int max_readdir_bytes; /* max readdir result (bytes) */
  58
  59         /*
  60          * everything above this point can be memcmp'd; everything below
  61          * is handled in compare_mount_options()
  62          */
  63
  64         char *snapdir_name;   /* default ".snap" */
  65 };
  66
  67 struct ceph_fs_client {
  68         struct super_block *sb;
  69
  70         struct ceph_mount_options *mount_options;
  71         struct ceph_client *client;
  72
  73         unsigned long mount_state;
  74         int min_caps;                  /* min caps i added */
  75
  76         struct ceph_mds_client *mdsc;
  77
  78         /* writeback */
  79         mempool_t *wb_pagevec_pool;
  80         struct workqueue_struct *wb_wq;
  81         struct workqueue_struct *pg_inv_wq;
  82         struct workqueue_struct *trunc_wq;
  83         atomic_long_t writeback_count;
  84
  85         struct backing_dev_info backing_dev_info;
  86
  87 #ifdef CONFIG_DEBUG_FS
  88         struct dentry *debugfs_dentry_lru, *debugfs_caps;
  89         struct dentry *debugfs_congestion_kb;
  90         struct dentry *debugfs_bdi;
  91         struct dentry *debugfs_mdsc, *debugfs_mdsmap;
  92 #endif
  93 };
  94
  95
  96 /*
  97  * File i/o capability.  This tracks shared state with the metadata
  98  * server that allows us to cache or writeback attributes or to read
  99  * and write data.  For any given inode, we should have one or more
 100  * capabilities, one issued by each metadata server, and our
 101  * cumulative access is the OR of all issued capabilities.
 102  *
 103  * Each cap is referenced by the inode's i_caps rbtree and by per-mds
 104  * session capability lists.
 105  */
 106 struct ceph_cap {
 107         struct ceph_inode_info *ci;
 108         struct rb_node ci_node;          /* per-ci cap tree */
 109         struct ceph_mds_session *session;
 110         struct list_head session_caps;   /* per-session caplist */
 111         int mds;
 112         u64 cap_id;       /* unique cap id (mds provided) */
 113         int issued;       /* latest, from the mds */
 114         int implemented;  /* implemented superset of issued (for revocation) */
 115         int mds_wanted;
 116         u32 seq, issue_seq, mseq;
 117         u32 cap_gen;      /* active/stale cycle */
 118         unsigned long last_used;
 119         struct list_head caps_item;
 120 };
 121
 122 #define CHECK_CAPS_NODELAY    1  /* do not delay any further */
 123 #define CHECK_CAPS_AUTHONLY   2  /* only check auth cap */
 124 #define CHECK_CAPS_FLUSH      4  /* flush any dirty caps */
 125
 126 /*
 127  * Snapped cap state that is pending flush to mds.  When a snapshot occurs,
 128  * we first complete any in-process sync writes and writeback any dirty
 129  * data before flushing the snapped state (tracked here) back to the MDS.
 130  */
 131 struct ceph_cap_snap {
 132         atomic_t nref;
 133         struct ceph_inode_info *ci;
 134         struct list_head ci_item, flushing_item;
 135
 136         u64 follows, flush_tid;
 137         int issued, dirty;
 138         struct ceph_snap_context *context;
 139
 140         umode_t mode;
 141         uid_t uid;
 142         gid_t gid;
 143
 144         struct ceph_buffer *xattr_blob;
 145         u64 xattr_version;
 146
 147         u64 size;
 148         struct timespec mtime, atime, ctime;
 149         u64 time_warp_seq;
 150         int writing;   /* a sync write is still in progress */
 151         int dirty_pages;     /* dirty pages awaiting writeback */
 152 };
 153
 154 static inline void ceph_put_cap_snap(struct ceph_cap_snap *capsnap)
 155 {
 156         if (atomic_dec_and_test(&capsnap->nref)) {
 157                 if (capsnap->xattr_blob)
 158                         ceph_buffer_put(capsnap->xattr_blob);
 159                 kfree(capsnap);
 160         }
 161 }
 162
 163 /*
 164  * The frag tree describes how a directory is fragmented, potentially across
 165  * multiple metadata servers.  It is also used to indicate points where
 166  * metadata authority is delegated, and whether/where metadata is replicated.
 167  *
 168  * A _leaf_ frag will be present in the i_fragtree IFF there is
 169  * delegation info.  That is, if mds >= 0 || ndist > 0.
 170  */
 171 #define CEPH_MAX_DIRFRAG_REP 4
 172
 173 struct ceph_inode_frag {
 174         struct rb_node node;
 175
 176         /* fragtree state */
 177         u32 frag;
 178         int split_by;         /* i.e. 2^(split_by) children */
 179
 180         /* delegation and replication info */
 181         int mds;              /* -1 if same authority as parent */
 182         int ndist;            /* >0 if replicated */
 183         int dist[CEPH_MAX_DIRFRAG_REP];
 184 };
 185
 186 /*
 187  * We cache inode xattrs as an encoded blob until they are first used,
 188  * at which point we parse them into an rbtree.
 189  */
 190 struct ceph_inode_xattr {
 191         struct rb_node node;
 192
 193         const char *name;
 194         int name_len;
 195         const char *val;
 196         int val_len;
 197         int dirty;
 198
 199         int should_free_name;
 200         int should_free_val;
 201 };
 202
 203 /*
 204  * Ceph dentry state
 205  */
 206 struct ceph_dentry_info {
 207         unsigned long flags;
 208         struct ceph_mds_session *lease_session;
 209         u32 lease_gen, lease_shared_gen;
 210         u32 lease_seq;
 211         unsigned long lease_renew_after, lease_renew_from;
 212         struct list_head lru;
 213         struct dentry *dentry;
 214         u64 time;
 215         u64 offset;
 216 };
 217
 218 /*
 219  * dentry flags
 220  *
 221  * The locking for D_COMPLETE is a bit odd:
 222  *  - we can clear it at almost any time (see ceph_d_prune)
 223  *  - it is only meaningful if:
 224  *    - we hold dir inode i_ceph_lock
 225  *    - we hold dir FILE_SHARED caps
 226  *    - the dentry D_COMPLETE is set
 227  */
 228 #define CEPH_D_COMPLETE 1  /* if set, d_u.d_subdirs is complete directory */
 229
 230 struct ceph_inode_xattrs_info {
 231         /*
 232          * (still encoded) xattr blob. we avoid the overhead of parsing
 233          * this until someone actually calls getxattr, etc.
 234          *
 235          * blob->vec.iov_len == 4 implies there are no xattrs; blob ==
 236          * NULL means we don't know.
 237         */
 238         struct ceph_buffer *blob, *prealloc_blob;
 239
 240         struct rb_root index;
 241         bool dirty;
 242         int count;
 243         int names_size;
 244         int vals_size;
 245         u64 version, index_version;
 246 };
 247
 248 /*
 249  * Ceph inode.
 250  */
 251 struct ceph_inode_info {
 252         struct ceph_vino i_vino;   /* ceph ino + snap */
 253
 254         spinlock_t i_ceph_lock;
 255
 256         u64 i_version;
 257         u32 i_time_warp_seq;
 258
 259         unsigned i_ceph_flags;
 260         unsigned long i_release_count;
 261
 262         struct ceph_dir_layout i_dir_layout;
 263         struct ceph_file_layout i_layout;
 264         char *i_symlink;
 265
 266         /* for dirs */
 267         struct timespec i_rctime;
 268         u64 i_rbytes, i_rfiles, i_rsubdirs;
 269         u64 i_files, i_subdirs;
 270         u64 i_max_offset;  /* largest readdir offset, set with D_COMPLETE */
 271
 272         struct rb_root i_fragtree;
 273         struct mutex i_fragtree_mutex;
 274
 275         struct ceph_inode_xattrs_info i_xattrs;
 276
 277         /* capabilities.  protected _both_ by i_ceph_lock and cap->session's
 278          * s_mutex. */
 279         struct rb_root i_caps;           /* cap list */
 280         struct ceph_cap *i_auth_cap;     /* authoritative cap, if any */
 281         unsigned i_dirty_caps, i_flushing_caps;     /* mask of dirtied fields */
 282         struct list_head i_dirty_item, i_flushing_item;
 283         u64 i_cap_flush_seq;
 284         /* we need to track cap writeback on a per-cap-bit basis, to allow
 285          * overlapping, pipelined cap flushes to the mds.  we can probably
 286          * reduce the tid to 8 bits if we're concerned about inode size. */
 287         u16 i_cap_flush_last_tid, i_cap_flush_tid[CEPH_CAP_BITS];
 288         wait_queue_head_t i_cap_wq;      /* threads waiting on a capability */
 289         unsigned long i_hold_caps_min; /* jiffies */
 290         unsigned long i_hold_caps_max; /* jiffies */
 291         struct list_head i_cap_delay_list;  /* for delayed cap release to mds */
 292         int i_cap_exporting_mds;         /* to handle cap migration between */
 293         unsigned i_cap_exporting_mseq;   /*  mds's. */
 294         unsigned i_cap_exporting_issued;
 295         struct ceph_cap_reservation i_cap_migration_resv;
 296         struct list_head i_cap_snaps;   /* snapped state pending flush to mds */
 297         struct ceph_snap_context *i_head_snapc;  /* set if wr_buffer_head > 0 or
 298                                                     dirty|flushing caps */
 299         unsigned i_snap_caps;           /* cap bits for snapped files */
 300
 301         int i_nr_by_mode[CEPH_FILE_MODE_NUM];  /* open file counts */
 302
 303         u32 i_truncate_seq;        /* last truncate to smaller size */
 304         u64 i_truncate_size;       /*  and the size we last truncated down to */
 305         int i_truncate_pending;    /*  still need to call vmtruncate */
 306
 307         u64 i_max_size;            /* max file size authorized by mds */
 308         u64 i_reported_size; /* (max_)size reported to or requested of mds */
 309         u64 i_wanted_max_size;     /* offset we'd like to write too */
 310         u64 i_requested_max_size;  /* max_size we've requested */
 311
 312         /* held references to caps */
 313         int i_pin_ref;
 314         int i_rd_ref, i_rdcache_ref, i_wr_ref, i_wb_ref;
 315         int i_wrbuffer_ref, i_wrbuffer_ref_head;
 316         u32 i_shared_gen;       /* increment each time we get FILE_SHARED */
 317         u32 i_rdcache_gen;      /* incremented each time we get FILE_CACHE. */
 318         u32 i_rdcache_revoking; /* RDCACHE gen to async invalidate, if any */
 319
 320         struct list_head i_unsafe_writes; /* uncommitted sync writes */
 321         struct list_head i_unsafe_dirops; /* uncommitted mds dir ops */
 322         spinlock_t i_unsafe_lock;
 323
 324         struct ceph_snap_realm *i_snap_realm; /* snap realm (if caps) */
 325         int i_snap_realm_counter; /* snap realm (if caps) */
 326         struct list_head i_snap_realm_item;
 327         struct list_head i_snap_flush_item;
 328
 329         struct work_struct i_wb_work;  /* writeback work */
 330         struct work_struct i_pg_inv_work;  /* page invalidation work */
 331
 332         struct work_struct i_vmtruncate_work;
 333
 334         struct inode vfs_inode; /* at end */
 335 };
 336
 337 static inline struct ceph_inode_info *ceph_inode(struct inode *inode)
 338 {
 339         return container_of(inode, struct ceph_inode_info, vfs_inode);
 340 }
 341
 342 static inline struct ceph_fs_client *ceph_inode_to_client(struct inode *inode)
 343 {
 344         return (struct ceph_fs_client *)inode->i_sb->s_fs_info;
 345 }
 346
 347 static inline struct ceph_fs_client *ceph_sb_to_client(struct super_block *sb)
 348 {
 349         return (struct ceph_fs_client *)sb->s_fs_info;
 350 }
 351
 352 static inline struct ceph_vino ceph_vino(struct inode *inode)
 353 {
 354         return ceph_inode(inode)->i_vino;
 355 }
 356
 357 /*
 358  * ino_t is <64 bits on many architectures, blech.
 359  *
 360  *               i_ino (kernel inode)   st_ino (userspace)
 361  * i386          32                     32
 362  * x86_64+ino32  64                     32
 363  * x86_64        64                     64
 364  */
 365 static inline u32 ceph_ino_to_ino32(__u64 vino)
 366 {
 367         u32 ino = vino & 0xffffffff;
 368         ino ^= vino >> 32;
 369         if (!ino)
 370                 ino = 1;
 371         return ino;
 372 }
 373
 374 /*
 375  * kernel i_ino value
 376  */
 377 static inline ino_t ceph_vino_to_ino(struct ceph_vino vino)
 378 {
 379 #if BITS_PER_LONG == 32
 380         return ceph_ino_to_ino32(vino.ino);
 381 #else
 382         return (ino_t)vino.ino;
 383 #endif
 384 }
 385
 386 /*
 387  * user-visible ino (stat, filldir)
 388  */
 389 #if BITS_PER_LONG == 32
 390 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
 391 {
 392         return ino;
 393 }
 394 #else
 395 static inline ino_t ceph_translate_ino(struct super_block *sb, ino_t ino)
 396 {
 397         if (ceph_test_mount_opt(ceph_sb_to_client(sb), INO32))
 398                 ino = ceph_ino_to_ino32(ino);
 399         return ino;
 400 }
 401 #endif
 402
 403
 404 /* for printf-style formatting */
 405 #define ceph_vinop(i) ceph_inode(i)->i_vino.ino, ceph_inode(i)->i_vino.snap
 406
 407 static inline u64 ceph_ino(struct inode *inode)
 408 {
 409         return ceph_inode(inode)->i_vino.ino;
 410 }
 411 static inline u64 ceph_snap(struct inode *inode)
 412 {
 413         return ceph_inode(inode)->i_vino.snap;
 414 }
 415
 416 static inline int ceph_ino_compare(struct inode *inode, void *data)
 417 {
 418         struct ceph_vino *pvino = (struct ceph_vino *)data;
 419         struct ceph_inode_info *ci = ceph_inode(inode);
 420         return ci->i_vino.ino == pvino->ino &&
 421                 ci->i_vino.snap == pvino->snap;
 422 }
 423
 424 static inline struct inode *ceph_find_inode(struct super_block *sb,
 425                                             struct ceph_vino vino)
 426 {
 427         ino_t t = ceph_vino_to_ino(vino);
 428         return ilookup5(sb, t, ceph_ino_compare, &vino);
 429 }
 430
 431
 432 /*
 433  * Ceph inode.
 434  */
 435 #define CEPH_I_NODELAY   4  /* do not delay cap release */
 436 #define CEPH_I_FLUSH     8  /* do not delay flush of dirty metadata */
 437 #define CEPH_I_NOFLUSH  16  /* do not flush dirty caps */
 438
 439 static inline void ceph_i_clear(struct inode *inode, unsigned mask)
 440 {
 441         struct ceph_inode_info *ci = ceph_inode(inode);
 442
 443         spin_lock(&ci->i_ceph_lock);
 444         ci->i_ceph_flags &= ~mask;
 445         spin_unlock(&ci->i_ceph_lock);
 446 }
 447
 448 static inline void ceph_i_set(struct inode *inode, unsigned mask)
 449 {
 450         struct ceph_inode_info *ci = ceph_inode(inode);
 451
 452         spin_lock(&ci->i_ceph_lock);
 453         ci->i_ceph_flags |= mask;
 454         spin_unlock(&ci->i_ceph_lock);
 455 }
 456
 457 static inline bool ceph_i_test(struct inode *inode, unsigned mask)
 458 {
 459         struct ceph_inode_info *ci = ceph_inode(inode);
 460         bool r;
 461
 462         spin_lock(&ci->i_ceph_lock);
 463         r = (ci->i_ceph_flags & mask) == mask;
 464         spin_unlock(&ci->i_ceph_lock);
 465         return r;
 466 }
 467
 468
 469 /* find a specific frag @f */
 470 extern struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci,
 471                                                 u32 f);
 472
 473 /*
 474  * choose fragment for value @v.  copy frag content to pfrag, if leaf
 475  * exists
 476  */
 477 extern u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
 478                             struct ceph_inode_frag *pfrag,
 479                             int *found);
 480
 481 static inline struct ceph_dentry_info *ceph_dentry(struct dentry *dentry)
 482 {
 483         return (struct ceph_dentry_info *)dentry->d_fsdata;
 484 }
 485
 486 static inline loff_t ceph_make_fpos(unsigned frag, unsigned off)
 487 {
 488         return ((loff_t)frag << 32) | (loff_t)off;
 489 }
 490
 491 /*
 492  * set/clear directory D_COMPLETE flag
 493  */
 494 void ceph_dir_set_complete(struct inode *inode);
 495 void ceph_dir_clear_complete(struct inode *inode);
 496 bool ceph_dir_test_complete(struct inode *inode);
 497
 498 /*
 499  * caps helpers
 500  */
 501 static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
 502 {
 503         return !RB_EMPTY_ROOT(&ci->i_caps);
 504 }
 505
 506 extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented);
 507 extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t);
 508 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
 509                                     struct ceph_cap *cap);
 510
 511 static inline int ceph_caps_issued(struct ceph_inode_info *ci)
 512 {
 513         int issued;
 514         spin_lock(&ci->i_ceph_lock);
 515         issued = __ceph_caps_issued(ci, NULL);
 516         spin_unlock(&ci->i_ceph_lock);
 517         return issued;
 518 }
 519
 520 static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
 521                                         int touch)
 522 {
 523         int r;
 524         spin_lock(&ci->i_ceph_lock);
 525         r = __ceph_caps_issued_mask(ci, mask, touch);
 526         spin_unlock(&ci->i_ceph_lock);
 527         return r;
 528 }
 529
 530 static inline int __ceph_caps_dirty(struct ceph_inode_info *ci)
 531 {
 532         return ci->i_dirty_caps | ci->i_flushing_caps;
 533 }
 534 extern int __ceph_mark_dirty_caps(struct ceph_inode_info *ci, int mask);
 535
 536 extern int ceph_caps_revoking(struct ceph_inode_info *ci, int mask);
 537 extern int __ceph_caps_used(struct ceph_inode_info *ci);
 538
 539 extern int __ceph_caps_file_wanted(struct ceph_inode_info *ci);
 540
 541 /*
 542  * wanted, by virtue of open file modes AND cap refs (buffered/cached data)
 543  */
 544 static inline int __ceph_caps_wanted(struct ceph_inode_info *ci)
 545 {
 546         int w = __ceph_caps_file_wanted(ci) | __ceph_caps_used(ci);
 547         if (w & CEPH_CAP_FILE_BUFFER)
 548                 w |= CEPH_CAP_FILE_EXCL;  /* we want EXCL if dirty data */
 549         return w;
 550 }
 551
 552 /* what the mds thinks we want */
 553 extern int __ceph_caps_mds_wanted(struct ceph_inode_info *ci);
 554
 555 extern void ceph_caps_init(struct ceph_mds_client *mdsc);
 556 extern void ceph_caps_finalize(struct ceph_mds_client *mdsc);
 557 extern void ceph_adjust_min_caps(struct ceph_mds_client *mdsc, int delta);
 558 extern int ceph_reserve_caps(struct ceph_mds_client *mdsc,
 559                              struct ceph_cap_reservation *ctx, int need);
 560 extern int ceph_unreserve_caps(struct ceph_mds_client *mdsc,
 561                                struct ceph_cap_reservation *ctx);
 562 extern void ceph_reservation_status(struct ceph_fs_client *client,
 563                                     int *total, int *avail, int *used,
 564                                     int *reserved, int *min);
 565
 566
 567
 568 /*
 569  * we keep buffered readdir results attached to file->private_data
 570  */
 571 #define CEPH_F_SYNC     1
 572 #define CEPH_F_ATEND    2
 573
 574 struct ceph_file_info {
 575         short fmode;     /* initialized on open */
 576         short flags;     /* CEPH_F_* */
 577
 578         /* readdir: position within the dir */
 579         u32 frag;
 580         struct ceph_mds_request *last_readdir;
 581
 582         /* readdir: position within a frag */
 583         unsigned offset;       /* offset of last chunk, adjusted for . and .. */
 584         u64 next_offset;       /* offset of next chunk (last_name's + 1) */
 585         char *last_name;       /* last entry in previous chunk */
 586         struct dentry *dentry; /* next dentry (for dcache readdir) */
 587         unsigned long dir_release_count;
 588
 589         /* used for -o dirstat read() on directory thing */
 590         char *dir_info;
 591         int dir_info_len;
 592 };
 593
 594
 595
 596 /*
 597  * A "snap realm" describes a subset of the file hierarchy sharing
 598  * the same set of snapshots that apply to it.  The realms themselves
 599  * are organized into a hierarchy, such that children inherit (some of)
 600  * the snapshots of their parents.
 601  *
 602  * All inodes within the realm that have capabilities are linked into a
 603  * per-realm list.
 604  */
 605 struct ceph_snap_realm {
 606         u64 ino;
 607         atomic_t nref;
 608         struct rb_node node;
 609
 610         u64 created, seq;
 611         u64 parent_ino;
 612         u64 parent_since;   /* snapid when our current parent became so */
 613
 614         u64 *prior_parent_snaps;      /* snaps inherited from any parents we */
 615         int num_prior_parent_snaps;   /*  had prior to parent_since */
 616         u64 *snaps;                   /* snaps specific to this realm */
 617         int num_snaps;
 618
 619         struct ceph_snap_realm *parent;
 620         struct list_head children;       /* list of child realms */
 621         struct list_head child_item;
 622
 623         struct list_head empty_item;     /* if i have ref==0 */
 624
 625         struct list_head dirty_item;     /* if realm needs new context */
 626
 627         /* the current set of snaps for this realm */
 628         struct ceph_snap_context *cached_context;
 629
 630         struct list_head inodes_with_caps;
 631         spinlock_t inodes_with_caps_lock;
 632 };
 633
 634 static inline int default_congestion_kb(void)
 635 {
 636         int congestion_kb;
 637
 638         /*
 639          * Copied from NFS
 640          *
 641          * congestion size, scale with available memory.
 642          *
 643          *  64MB:    8192k
 644          * 128MB:   11585k
 645          * 256MB:   16384k
 646          * 512MB:   23170k
 647          *   1GB:   32768k
 648          *   2GB:   46340k
 649          *   4GB:   65536k
 650          *   8GB:   92681k
 651          *  16GB:  131072k
 652          *
 653          * This allows larger machines to have larger/more transfers.
 654          * Limit the default to 256M
 655          */
 656         congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
 657         if (congestion_kb > 256*1024)
 658                 congestion_kb = 256*1024;
 659
 660         return congestion_kb;
 661 }
 662
 663
 664
 665 /* snap.c */
 666 struct ceph_snap_realm *ceph_lookup_snap_realm(struct ceph_mds_client *mdsc,
 667                                                u64 ino);
 668 extern void ceph_get_snap_realm(struct ceph_mds_client *mdsc,
 669                                 struct ceph_snap_realm *realm);
 670 extern void ceph_put_snap_realm(struct ceph_mds_client *mdsc,
 671                                 struct ceph_snap_realm *realm);
 672 extern int ceph_update_snap_trace(struct ceph_mds_client *m,
 673                                   void *p, void *e, bool deletion);
 674 extern void ceph_handle_snap(struct ceph_mds_client *mdsc,
 675                              struct ceph_mds_session *session,
 676                              struct ceph_msg *msg);
 677 extern void ceph_queue_cap_snap(struct ceph_inode_info *ci);
 678 extern int __ceph_finish_cap_snap(struct ceph_inode_info *ci,
 679                                   struct ceph_cap_snap *capsnap);
 680 extern void ceph_cleanup_empty_realms(struct ceph_mds_client *mdsc);
 681
 682 /*
 683  * a cap_snap is "pending" if it is still awaiting an in-progress
 684  * sync write (that may/may not still update size, mtime, etc.).
 685  */
 686 static inline bool __ceph_have_pending_cap_snap(struct ceph_inode_info *ci)
 687 {
 688         return !list_empty(&ci->i_cap_snaps) &&
 689                 list_entry(ci->i_cap_snaps.prev, struct ceph_cap_snap,
 690                            ci_item)->writing;
 691 }
 692
 693 /* inode.c */
 694 extern const struct inode_operations ceph_file_iops;
 695
 696 extern struct inode *ceph_alloc_inode(struct super_block *sb);
 697 extern void ceph_destroy_inode(struct inode *inode);
 698
 699 extern struct inode *ceph_get_inode(struct super_block *sb,
 700                                     struct ceph_vino vino);
 701 extern struct inode *ceph_get_snapdir(struct inode *parent);
 702 extern int ceph_fill_file_size(struct inode *inode, int issued,
 703                                u32 truncate_seq, u64 truncate_size, u64 size);
 704 extern void ceph_fill_file_time(struct inode *inode, int issued,
 705                                 u64 time_warp_seq, struct timespec *ctime,
 706                                 struct timespec *mtime, struct timespec *atime);
 707 extern int ceph_fill_trace(struct super_block *sb,
 708                            struct ceph_mds_request *req,
 709                            struct ceph_mds_session *session);
 710 extern int ceph_readdir_prepopulate(struct ceph_mds_request *req,
 711                                     struct ceph_mds_session *session);
 712
 713 extern int ceph_inode_holds_cap(struct inode *inode, int mask);
 714
 715 extern int ceph_inode_set_size(struct inode *inode, loff_t size);
 716 extern void __ceph_do_pending_vmtruncate(struct inode *inode);
 717 extern void ceph_queue_vmtruncate(struct inode *inode);
 718
 719 extern void ceph_queue_invalidate(struct inode *inode);
 720 extern void ceph_queue_writeback(struct inode *inode);
 721
 722 extern int ceph_do_getattr(struct inode *inode, int mask);
 723 extern int ceph_permission(struct inode *inode, int mask);
 724 extern int ceph_setattr(struct dentry *dentry, struct iattr *attr);
 725 extern int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
 726                         struct kstat *stat);
 727
 728 /* xattr.c */
 729 extern int ceph_setxattr(struct dentry *, const char *, const void *,
 730                          size_t, int);
 731 extern ssize_t ceph_getxattr(struct dentry *, const char *, void *, size_t);
 732 extern ssize_t ceph_listxattr(struct dentry *, char *, size_t);
 733 extern int ceph_removexattr(struct dentry *, const char *);
 734 extern void __ceph_build_xattrs_blob(struct ceph_inode_info *ci);
 735 extern void __ceph_destroy_xattrs(struct ceph_inode_info *ci);
 736
 737 /* caps.c */
 738 extern const char *ceph_cap_string(int c);
 739 extern void ceph_handle_caps(struct ceph_mds_session *session,
 740                              struct ceph_msg *msg);
 741 extern int ceph_add_cap(struct inode *inode,
 742                         struct ceph_mds_session *session, u64 cap_id,
 743                         int fmode, unsigned issued, unsigned wanted,
 744                         unsigned cap, unsigned seq, u64 realmino, int flags,
 745                         struct ceph_cap_reservation *caps_reservation);
 746 extern void __ceph_remove_cap(struct ceph_cap *cap);
 747 static inline void ceph_remove_cap(struct ceph_cap *cap)
 748 {
 749         spin_lock(&cap->ci->i_ceph_lock);
 750         __ceph_remove_cap(cap);
 751         spin_unlock(&cap->ci->i_ceph_lock);
 752 }
 753 extern void ceph_put_cap(struct ceph_mds_client *mdsc,
 754                          struct ceph_cap *cap);
 755
 756 extern void ceph_queue_caps_release(struct inode *inode);
 757 extern int ceph_write_inode(struct inode *inode, struct writeback_control *wbc);
 758 extern int ceph_fsync(struct file *file, loff_t start, loff_t end,
 759                       int datasync);
 760 extern void ceph_kick_flushing_caps(struct ceph_mds_client *mdsc,
 761                                     struct ceph_mds_session *session);
 762 extern struct ceph_cap *ceph_get_cap_for_mds(struct ceph_inode_info *ci,
 763                                              int mds);
 764 extern int ceph_get_cap_mds(struct inode *inode);
 765 extern void ceph_get_cap_refs(struct ceph_inode_info *ci, int caps);
 766 extern void ceph_put_cap_refs(struct ceph_inode_info *ci, int had);
 767 extern void ceph_put_wrbuffer_cap_refs(struct ceph_inode_info *ci, int nr,
 768                                        struct ceph_snap_context *snapc);
 769 extern void __ceph_flush_snaps(struct ceph_inode_info *ci,
 770                                struct ceph_mds_session **psession,
 771                                int again);
 772 extern void ceph_check_caps(struct ceph_inode_info *ci, int flags,
 773                             struct ceph_mds_session *session);
 774 extern void ceph_check_delayed_caps(struct ceph_mds_client *mdsc);
 775 extern void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc);
 776
 777 extern int ceph_encode_inode_release(void **p, struct inode *inode,
 778                                      int mds, int drop, int unless, int force);
 779 extern int ceph_encode_dentry_release(void **p, struct dentry *dn,
 780                                       int mds, int drop, int unless);
 781
 782 extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want,
 783                          int *got, loff_t endoff);
 784
 785 /* for counting open files by mode */
 786 static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)
 787 {
 788         ci->i_nr_by_mode[mode]++;
 789 }
 790 extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);
 791
 792 /* addr.c */
 793 extern const struct address_space_operations ceph_aops;
 794 extern int ceph_mmap(struct file *file, struct vm_area_struct *vma);
 795
 796 /* file.c */
 797 extern const struct file_operations ceph_file_fops;
 798 extern const struct address_space_operations ceph_aops;
 799 extern int ceph_copy_to_page_vector(struct page **pages,
 800                                     const char *data,
 801                                     loff_t off, size_t len);
 802 extern int ceph_copy_from_page_vector(struct page **pages,
 803                                     char *data,
 804                                     loff_t off, size_t len);
 805 extern struct page **ceph_alloc_page_vector(int num_pages, gfp_t flags);
 806 extern int ceph_open(struct inode *inode, struct file *file);
 807 extern struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry,
 808                                        struct nameidata *nd, int mode,
 809                                        int locked_dir);
 810 extern int ceph_release(struct inode *inode, struct file *filp);
 811
 812 /* dir.c */
 813 extern const struct file_operations ceph_dir_fops;
 814 extern const struct inode_operations ceph_dir_iops;
 815 extern const struct dentry_operations ceph_dentry_ops, ceph_snap_dentry_ops,
 816         ceph_snapdir_dentry_ops;
 817
 818 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
 819 extern int ceph_handle_snapdir(struct ceph_mds_request *req,
 820                                struct dentry *dentry, int err);
 821 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 822                                          struct dentry *dentry, int err);
 823
 824 extern void ceph_dentry_lru_add(struct dentry *dn);
 825 extern void ceph_dentry_lru_touch(struct dentry *dn);
 826 extern void ceph_dentry_lru_del(struct dentry *dn);
 827 extern void ceph_invalidate_dentry_lease(struct dentry *dentry);
 828 extern unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn);
 829 extern struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry);
 830
 831 /*
 832  * our d_ops vary depending on whether the inode is live,
 833  * snapshotted (read-only), or a virtual ".snap" directory.
 834  */
 835 int ceph_init_dentry(struct dentry *dentry);
 836
 837
 838 /* ioctl.c */
 839 extern long ceph_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
 840
 841 /* export.c */
 842 extern const struct export_operations ceph_export_ops;
 843
 844 /* locks.c */
 845 extern int ceph_lock(struct file *file, int cmd, struct file_lock *fl);
 846 extern int ceph_flock(struct file *file, int cmd, struct file_lock *fl);
 847 extern void ceph_count_locks(struct inode *inode, int *p_num, int *f_num);
 848 extern int ceph_encode_locks(struct inode *i, struct ceph_pagelist *p,
 849                              int p_locks, int f_locks);
 850 extern int lock_to_ceph_filelock(struct file_lock *fl, struct ceph_filelock *c);
 851
 852 /* debugfs.c */
 853 extern int ceph_fs_debugfs_init(struct ceph_fs_client *client);
 854 extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
 855
 856 #endif /* _FS_CEPH_SUPER_H */