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