Pileus Git - ~andy/linux/blob - fs/ceph/super.c

   1
   2 #include <linux/ceph/ceph_debug.h>
   3
   4 #include <linux/backing-dev.h>
   5 #include <linux/ctype.h>
   6 #include <linux/fs.h>
   7 #include <linux/inet.h>
   8 #include <linux/in6.h>
   9 #include <linux/module.h>
  10 #include <linux/mount.h>
  11 #include <linux/parser.h>
  12 #include <linux/sched.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/slab.h>
  15 #include <linux/statfs.h>
  16 #include <linux/string.h>
  17
  18 #include "super.h"
  19 #include "mds_client.h"
  20
  21 #include <linux/ceph/ceph_features.h>
  22 #include <linux/ceph/decode.h>
  23 #include <linux/ceph/mon_client.h>
  24 #include <linux/ceph/auth.h>
  25 #include <linux/ceph/debugfs.h>
  26
  27 /*
  28  * Ceph superblock operations
  29  *
  30  * Handle the basics of mounting, unmounting.
  31  */
  32
  33 /*
  34  * super ops
  35  */
  36 static void ceph_put_super(struct super_block *s)
  37 {
  38         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
  39
  40         dout("put_super\n");
  41         ceph_mdsc_close_sessions(fsc->mdsc);
  42
  43         /*
  44          * ensure we release the bdi before put_anon_super releases
  45          * the device name.
  46          */
  47         if (s->s_bdi == &fsc->backing_dev_info) {
  48                 bdi_unregister(&fsc->backing_dev_info);
  49                 s->s_bdi = NULL;
  50         }
  51
  52         return;
  53 }
  54
  55 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
  56 {
  57         struct ceph_fs_client *fsc = ceph_inode_to_client(dentry->d_inode);
  58         struct ceph_monmap *monmap = fsc->client->monc.monmap;
  59         struct ceph_statfs st;
  60         u64 fsid;
  61         int err;
  62
  63         dout("statfs\n");
  64         err = ceph_monc_do_statfs(&fsc->client->monc, &st);
  65         if (err < 0)
  66                 return err;
  67
  68         /* fill in kstatfs */
  69         buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
  70
  71         /*
  72          * express utilization in terms of large blocks to avoid
  73          * overflow on 32-bit machines.
  74          */
  75         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
  76         buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
  77         buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  78         buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  79
  80         buf->f_files = le64_to_cpu(st.num_objects);
  81         buf->f_ffree = -1;
  82         buf->f_namelen = NAME_MAX;
  83         buf->f_frsize = PAGE_CACHE_SIZE;
  84
  85         /* leave fsid little-endian, regardless of host endianness */
  86         fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
  87         buf->f_fsid.val[0] = fsid & 0xffffffff;
  88         buf->f_fsid.val[1] = fsid >> 32;
  89
  90         return 0;
  91 }
  92
  93
  94 static int ceph_sync_fs(struct super_block *sb, int wait)
  95 {
  96         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
  97
  98         if (!wait) {
  99                 dout("sync_fs (non-blocking)\n");
 100                 ceph_flush_dirty_caps(fsc->mdsc);
 101                 dout("sync_fs (non-blocking) done\n");
 102                 return 0;
 103         }
 104
 105         dout("sync_fs (blocking)\n");
 106         ceph_osdc_sync(&fsc->client->osdc);
 107         ceph_mdsc_sync(fsc->mdsc);
 108         dout("sync_fs (blocking) done\n");
 109         return 0;
 110 }
 111
 112 /*
 113  * mount options
 114  */
 115 enum {
 116         Opt_wsize,
 117         Opt_rsize,
 118         Opt_rasize,
 119         Opt_caps_wanted_delay_min,
 120         Opt_caps_wanted_delay_max,
 121         Opt_cap_release_safety,
 122         Opt_readdir_max_entries,
 123         Opt_readdir_max_bytes,
 124         Opt_congestion_kb,
 125         Opt_last_int,
 126         /* int args above */
 127         Opt_snapdirname,
 128         Opt_last_string,
 129         /* string args above */
 130         Opt_dirstat,
 131         Opt_nodirstat,
 132         Opt_rbytes,
 133         Opt_norbytes,
 134         Opt_asyncreaddir,
 135         Opt_noasyncreaddir,
 136         Opt_dcache,
 137         Opt_nodcache,
 138         Opt_ino32,
 139         Opt_noino32,
 140 };
 141
 142 static match_table_t fsopt_tokens = {
 143         {Opt_wsize, "wsize=%d"},
 144         {Opt_rsize, "rsize=%d"},
 145         {Opt_rasize, "rasize=%d"},
 146         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
 147         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
 148         {Opt_cap_release_safety, "cap_release_safety=%d"},
 149         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
 150         {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
 151         {Opt_congestion_kb, "write_congestion_kb=%d"},
 152         /* int args above */
 153         {Opt_snapdirname, "snapdirname=%s"},
 154         /* string args above */
 155         {Opt_dirstat, "dirstat"},
 156         {Opt_nodirstat, "nodirstat"},
 157         {Opt_rbytes, "rbytes"},
 158         {Opt_norbytes, "norbytes"},
 159         {Opt_asyncreaddir, "asyncreaddir"},
 160         {Opt_noasyncreaddir, "noasyncreaddir"},
 161         {Opt_dcache, "dcache"},
 162         {Opt_nodcache, "nodcache"},
 163         {Opt_ino32, "ino32"},
 164         {Opt_noino32, "noino32"},
 165         {-1, NULL}
 166 };
 167
 168 static int parse_fsopt_token(char *c, void *private)
 169 {
 170         struct ceph_mount_options *fsopt = private;
 171         substring_t argstr[MAX_OPT_ARGS];
 172         int token, intval, ret;
 173
 174         token = match_token((char *)c, fsopt_tokens, argstr);
 175         if (token < 0)
 176                 return -EINVAL;
 177
 178         if (token < Opt_last_int) {
 179                 ret = match_int(&argstr[0], &intval);
 180                 if (ret < 0) {
 181                         pr_err("bad mount option arg (not int) "
 182                                "at '%s'\n", c);
 183                         return ret;
 184                 }
 185                 dout("got int token %d val %d\n", token, intval);
 186         } else if (token > Opt_last_int && token < Opt_last_string) {
 187                 dout("got string token %d val %s\n", token,
 188                      argstr[0].from);
 189         } else {
 190                 dout("got token %d\n", token);
 191         }
 192
 193         switch (token) {
 194         case Opt_snapdirname:
 195                 kfree(fsopt->snapdir_name);
 196                 fsopt->snapdir_name = kstrndup(argstr[0].from,
 197                                                argstr[0].to-argstr[0].from,
 198                                                GFP_KERNEL);
 199                 if (!fsopt->snapdir_name)
 200                         return -ENOMEM;
 201                 break;
 202
 203                 /* misc */
 204         case Opt_wsize:
 205                 fsopt->wsize = intval;
 206                 break;
 207         case Opt_rsize:
 208                 fsopt->rsize = intval;
 209                 break;
 210         case Opt_rasize:
 211                 fsopt->rasize = intval;
 212                 break;
 213         case Opt_caps_wanted_delay_min:
 214                 fsopt->caps_wanted_delay_min = intval;
 215                 break;
 216         case Opt_caps_wanted_delay_max:
 217                 fsopt->caps_wanted_delay_max = intval;
 218                 break;
 219         case Opt_readdir_max_entries:
 220                 fsopt->max_readdir = intval;
 221                 break;
 222         case Opt_readdir_max_bytes:
 223                 fsopt->max_readdir_bytes = intval;
 224                 break;
 225         case Opt_congestion_kb:
 226                 fsopt->congestion_kb = intval;
 227                 break;
 228         case Opt_dirstat:
 229                 fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
 230                 break;
 231         case Opt_nodirstat:
 232                 fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
 233                 break;
 234         case Opt_rbytes:
 235                 fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
 236                 break;
 237         case Opt_norbytes:
 238                 fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
 239                 break;
 240         case Opt_asyncreaddir:
 241                 fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
 242                 break;
 243         case Opt_noasyncreaddir:
 244                 fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
 245                 break;
 246         case Opt_dcache:
 247                 fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
 248                 break;
 249         case Opt_nodcache:
 250                 fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
 251                 break;
 252         case Opt_ino32:
 253                 fsopt->flags |= CEPH_MOUNT_OPT_INO32;
 254                 break;
 255         case Opt_noino32:
 256                 fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
 257                 break;
 258         default:
 259                 BUG_ON(token);
 260         }
 261         return 0;
 262 }
 263
 264 static void destroy_mount_options(struct ceph_mount_options *args)
 265 {
 266         dout("destroy_mount_options %p\n", args);
 267         kfree(args->snapdir_name);
 268         kfree(args);
 269 }
 270
 271 static int strcmp_null(const char *s1, const char *s2)
 272 {
 273         if (!s1 && !s2)
 274                 return 0;
 275         if (s1 && !s2)
 276                 return -1;
 277         if (!s1 && s2)
 278                 return 1;
 279         return strcmp(s1, s2);
 280 }
 281
 282 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
 283                                  struct ceph_options *new_opt,
 284                                  struct ceph_fs_client *fsc)
 285 {
 286         struct ceph_mount_options *fsopt1 = new_fsopt;
 287         struct ceph_mount_options *fsopt2 = fsc->mount_options;
 288         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
 289         int ret;
 290
 291         ret = memcmp(fsopt1, fsopt2, ofs);
 292         if (ret)
 293                 return ret;
 294
 295         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
 296         if (ret)
 297                 return ret;
 298
 299         return ceph_compare_options(new_opt, fsc->client);
 300 }
 301
 302 static int parse_mount_options(struct ceph_mount_options **pfsopt,
 303                                struct ceph_options **popt,
 304                                int flags, char *options,
 305                                const char *dev_name,
 306                                const char **path)
 307 {
 308         struct ceph_mount_options *fsopt;
 309         const char *dev_name_end;
 310         int err = -ENOMEM;
 311
 312         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
 313         if (!fsopt)
 314                 return -ENOMEM;
 315
 316         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
 317
 318         fsopt->sb_flags = flags;
 319         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
 320
 321         fsopt->rsize = CEPH_RSIZE_DEFAULT;
 322         fsopt->rasize = CEPH_RASIZE_DEFAULT;
 323         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
 324         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
 325         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
 326         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
 327         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
 328         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
 329         fsopt->congestion_kb = default_congestion_kb();
 330
 331         /* ip1[:port1][,ip2[:port2]...]:/subdir/in/fs */
 332         err = -EINVAL;
 333         if (!dev_name)
 334                 goto out;
 335         *path = strstr(dev_name, ":/");
 336         if (*path == NULL) {
 337                 pr_err("device name is missing path (no :/ in %s)\n",
 338                                 dev_name);
 339                 goto out;
 340         }
 341         dev_name_end = *path;
 342         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
 343
 344         /* path on server */
 345         *path += 2;
 346         dout("server path '%s'\n", *path);
 347
 348         *popt = ceph_parse_options(options, dev_name, dev_name_end,
 349                                  parse_fsopt_token, (void *)fsopt);
 350         if (IS_ERR(*popt)) {
 351                 err = PTR_ERR(*popt);
 352                 goto out;
 353         }
 354
 355         /* success */
 356         *pfsopt = fsopt;
 357         return 0;
 358
 359 out:
 360         destroy_mount_options(fsopt);
 361         return err;
 362 }
 363
 364 /**
 365  * ceph_show_options - Show mount options in /proc/mounts
 366  * @m: seq_file to write to
 367  * @root: root of that (sub)tree
 368  */
 369 static int ceph_show_options(struct seq_file *m, struct dentry *root)
 370 {
 371         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
 372         struct ceph_mount_options *fsopt = fsc->mount_options;
 373         struct ceph_options *opt = fsc->client->options;
 374
 375         if (opt->flags & CEPH_OPT_FSID)
 376                 seq_printf(m, ",fsid=%pU", &opt->fsid);
 377         if (opt->flags & CEPH_OPT_NOSHARE)
 378                 seq_puts(m, ",noshare");
 379         if (opt->flags & CEPH_OPT_NOCRC)
 380                 seq_puts(m, ",nocrc");
 381
 382         if (opt->name)
 383                 seq_printf(m, ",name=%s", opt->name);
 384         if (opt->key)
 385                 seq_puts(m, ",secret=<hidden>");
 386
 387         if (opt->mount_timeout != CEPH_MOUNT_TIMEOUT_DEFAULT)
 388                 seq_printf(m, ",mount_timeout=%d", opt->mount_timeout);
 389         if (opt->osd_idle_ttl != CEPH_OSD_IDLE_TTL_DEFAULT)
 390                 seq_printf(m, ",osd_idle_ttl=%d", opt->osd_idle_ttl);
 391         if (opt->osd_timeout != CEPH_OSD_TIMEOUT_DEFAULT)
 392                 seq_printf(m, ",osdtimeout=%d", opt->osd_timeout);
 393         if (opt->osd_keepalive_timeout != CEPH_OSD_KEEPALIVE_DEFAULT)
 394                 seq_printf(m, ",osdkeepalivetimeout=%d",
 395                            opt->osd_keepalive_timeout);
 396
 397         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
 398                 seq_puts(m, ",dirstat");
 399         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
 400                 seq_puts(m, ",norbytes");
 401         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
 402                 seq_puts(m, ",noasyncreaddir");
 403         if (fsopt->flags & CEPH_MOUNT_OPT_DCACHE)
 404                 seq_puts(m, ",dcache");
 405         else
 406                 seq_puts(m, ",nodcache");
 407
 408         if (fsopt->wsize)
 409                 seq_printf(m, ",wsize=%d", fsopt->wsize);
 410         if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
 411                 seq_printf(m, ",rsize=%d", fsopt->rsize);
 412         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
 413                 seq_printf(m, ",rasize=%d", fsopt->rasize);
 414         if (fsopt->congestion_kb != default_congestion_kb())
 415                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
 416         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
 417                 seq_printf(m, ",caps_wanted_delay_min=%d",
 418                          fsopt->caps_wanted_delay_min);
 419         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
 420                 seq_printf(m, ",caps_wanted_delay_max=%d",
 421                            fsopt->caps_wanted_delay_max);
 422         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
 423                 seq_printf(m, ",cap_release_safety=%d",
 424                            fsopt->cap_release_safety);
 425         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
 426                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
 427         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
 428                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
 429         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 430                 seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
 431         return 0;
 432 }
 433
 434 /*
 435  * handle any mon messages the standard library doesn't understand.
 436  * return error if we don't either.
 437  */
 438 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
 439 {
 440         struct ceph_fs_client *fsc = client->private;
 441         int type = le16_to_cpu(msg->hdr.type);
 442
 443         switch (type) {
 444         case CEPH_MSG_MDS_MAP:
 445                 ceph_mdsc_handle_map(fsc->mdsc, msg);
 446                 return 0;
 447
 448         default:
 449                 return -1;
 450         }
 451 }
 452
 453 /*
 454  * create a new fs client
 455  */
 456 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 457                                         struct ceph_options *opt)
 458 {
 459         struct ceph_fs_client *fsc;
 460         const unsigned supported_features =
 461                 CEPH_FEATURE_FLOCK |
 462                 CEPH_FEATURE_DIRLAYOUTHASH;
 463         const unsigned required_features = 0;
 464         int err = -ENOMEM;
 465
 466         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
 467         if (!fsc)
 468                 return ERR_PTR(-ENOMEM);
 469
 470         fsc->client = ceph_create_client(opt, fsc, supported_features,
 471                                          required_features);
 472         if (IS_ERR(fsc->client)) {
 473                 err = PTR_ERR(fsc->client);
 474                 goto fail;
 475         }
 476         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 477         fsc->client->monc.want_mdsmap = 1;
 478
 479         fsc->mount_options = fsopt;
 480
 481         fsc->sb = NULL;
 482         fsc->mount_state = CEPH_MOUNT_MOUNTING;
 483
 484         atomic_long_set(&fsc->writeback_count, 0);
 485
 486         err = bdi_init(&fsc->backing_dev_info);
 487         if (err < 0)
 488                 goto fail_client;
 489
 490         err = -ENOMEM;
 491         /*
 492          * The number of concurrent works can be high but they don't need
 493          * to be processed in parallel, limit concurrency.
 494          */
 495         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
 496         if (fsc->wb_wq == NULL)
 497                 goto fail_bdi;
 498         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
 499         if (fsc->pg_inv_wq == NULL)
 500                 goto fail_wb_wq;
 501         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
 502         if (fsc->trunc_wq == NULL)
 503                 goto fail_pg_inv_wq;
 504
 505         /* set up mempools */
 506         err = -ENOMEM;
 507         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
 508                               fsc->mount_options->wsize >> PAGE_CACHE_SHIFT);
 509         if (!fsc->wb_pagevec_pool)
 510                 goto fail_trunc_wq;
 511
 512         /* caps */
 513         fsc->min_caps = fsopt->max_readdir;
 514
 515         return fsc;
 516
 517 fail_trunc_wq:
 518         destroy_workqueue(fsc->trunc_wq);
 519 fail_pg_inv_wq:
 520         destroy_workqueue(fsc->pg_inv_wq);
 521 fail_wb_wq:
 522         destroy_workqueue(fsc->wb_wq);
 523 fail_bdi:
 524         bdi_destroy(&fsc->backing_dev_info);
 525 fail_client:
 526         ceph_destroy_client(fsc->client);
 527 fail:
 528         kfree(fsc);
 529         return ERR_PTR(err);
 530 }
 531
 532 static void destroy_fs_client(struct ceph_fs_client *fsc)
 533 {
 534         dout("destroy_fs_client %p\n", fsc);
 535
 536         destroy_workqueue(fsc->wb_wq);
 537         destroy_workqueue(fsc->pg_inv_wq);
 538         destroy_workqueue(fsc->trunc_wq);
 539
 540         bdi_destroy(&fsc->backing_dev_info);
 541
 542         mempool_destroy(fsc->wb_pagevec_pool);
 543
 544         destroy_mount_options(fsc->mount_options);
 545
 546         ceph_fs_debugfs_cleanup(fsc);
 547
 548         ceph_destroy_client(fsc->client);
 549
 550         kfree(fsc);
 551         dout("destroy_fs_client %p done\n", fsc);
 552 }
 553
 554 /*
 555  * caches
 556  */
 557 struct kmem_cache *ceph_inode_cachep;
 558 struct kmem_cache *ceph_cap_cachep;
 559 struct kmem_cache *ceph_dentry_cachep;
 560 struct kmem_cache *ceph_file_cachep;
 561
 562 static void ceph_inode_init_once(void *foo)
 563 {
 564         struct ceph_inode_info *ci = foo;
 565         inode_init_once(&ci->vfs_inode);
 566 }
 567
 568 static int __init init_caches(void)
 569 {
 570         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 571                                       sizeof(struct ceph_inode_info),
 572                                       __alignof__(struct ceph_inode_info),
 573                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
 574                                       ceph_inode_init_once);
 575         if (ceph_inode_cachep == NULL)
 576                 return -ENOMEM;
 577
 578         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 579                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 580         if (ceph_cap_cachep == NULL)
 581                 goto bad_cap;
 582
 583         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 584                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 585         if (ceph_dentry_cachep == NULL)
 586                 goto bad_dentry;
 587
 588         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
 589                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 590         if (ceph_file_cachep == NULL)
 591                 goto bad_file;
 592
 593         return 0;
 594
 595 bad_file:
 596         kmem_cache_destroy(ceph_dentry_cachep);
 597 bad_dentry:
 598         kmem_cache_destroy(ceph_cap_cachep);
 599 bad_cap:
 600         kmem_cache_destroy(ceph_inode_cachep);
 601         return -ENOMEM;
 602 }
 603
 604 static void destroy_caches(void)
 605 {
 606         kmem_cache_destroy(ceph_inode_cachep);
 607         kmem_cache_destroy(ceph_cap_cachep);
 608         kmem_cache_destroy(ceph_dentry_cachep);
 609         kmem_cache_destroy(ceph_file_cachep);
 610 }
 611
 612
 613 /*
 614  * ceph_umount_begin - initiate forced umount.  Tear down down the
 615  * mount, skipping steps that may hang while waiting for server(s).
 616  */
 617 static void ceph_umount_begin(struct super_block *sb)
 618 {
 619         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 620
 621         dout("ceph_umount_begin - starting forced umount\n");
 622         if (!fsc)
 623                 return;
 624         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
 625         return;
 626 }
 627
 628 static const struct super_operations ceph_super_ops = {
 629         .alloc_inode    = ceph_alloc_inode,
 630         .destroy_inode  = ceph_destroy_inode,
 631         .write_inode    = ceph_write_inode,
 632         .sync_fs        = ceph_sync_fs,
 633         .put_super      = ceph_put_super,
 634         .show_options   = ceph_show_options,
 635         .statfs         = ceph_statfs,
 636         .umount_begin   = ceph_umount_begin,
 637 };
 638
 639 /*
 640  * Bootstrap mount by opening the root directory.  Note the mount
 641  * @started time from caller, and time out if this takes too long.
 642  */
 643 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 644                                        const char *path,
 645                                        unsigned long started)
 646 {
 647         struct ceph_mds_client *mdsc = fsc->mdsc;
 648         struct ceph_mds_request *req = NULL;
 649         int err;
 650         struct dentry *root;
 651
 652         /* open dir */
 653         dout("open_root_inode opening '%s'\n", path);
 654         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 655         if (IS_ERR(req))
 656                 return ERR_CAST(req);
 657         req->r_path1 = kstrdup(path, GFP_NOFS);
 658         req->r_ino1.ino = CEPH_INO_ROOT;
 659         req->r_ino1.snap = CEPH_NOSNAP;
 660         req->r_started = started;
 661         req->r_timeout = fsc->client->options->mount_timeout * HZ;
 662         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 663         req->r_num_caps = 2;
 664         err = ceph_mdsc_do_request(mdsc, NULL, req);
 665         if (err == 0) {
 666                 struct inode *inode = req->r_target_inode;
 667                 req->r_target_inode = NULL;
 668                 dout("open_root_inode success\n");
 669                 if (ceph_ino(inode) == CEPH_INO_ROOT &&
 670                     fsc->sb->s_root == NULL) {
 671                         root = d_make_root(inode);
 672                         if (!root) {
 673                                 root = ERR_PTR(-ENOMEM);
 674                                 goto out;
 675                         }
 676                 } else {
 677                         root = d_obtain_alias(inode);
 678                 }
 679                 ceph_init_dentry(root);
 680                 dout("open_root_inode success, root dentry is %p\n", root);
 681         } else {
 682                 root = ERR_PTR(err);
 683         }
 684 out:
 685         ceph_mdsc_put_request(req);
 686         return root;
 687 }
 688
 689
 690
 691
 692 /*
 693  * mount: join the ceph cluster, and open root directory.
 694  */
 695 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 696                       const char *path)
 697 {
 698         int err;
 699         unsigned long started = jiffies;  /* note the start time */
 700         struct dentry *root;
 701         int first = 0;   /* first vfsmount for this super_block */
 702
 703         dout("mount start\n");
 704         mutex_lock(&fsc->client->mount_mutex);
 705
 706         err = __ceph_open_session(fsc->client, started);
 707         if (err < 0)
 708                 goto out;
 709
 710         dout("mount opening root\n");
 711         root = open_root_dentry(fsc, "", started);
 712         if (IS_ERR(root)) {
 713                 err = PTR_ERR(root);
 714                 goto out;
 715         }
 716         if (fsc->sb->s_root) {
 717                 dput(root);
 718         } else {
 719                 fsc->sb->s_root = root;
 720                 first = 1;
 721
 722                 err = ceph_fs_debugfs_init(fsc);
 723                 if (err < 0)
 724                         goto fail;
 725         }
 726
 727         if (path[0] == 0) {
 728                 dget(root);
 729         } else {
 730                 dout("mount opening base mountpoint\n");
 731                 root = open_root_dentry(fsc, path, started);
 732                 if (IS_ERR(root)) {
 733                         err = PTR_ERR(root);
 734                         goto fail;
 735                 }
 736         }
 737
 738         fsc->mount_state = CEPH_MOUNT_MOUNTED;
 739         dout("mount success\n");
 740         mutex_unlock(&fsc->client->mount_mutex);
 741         return root;
 742
 743 out:
 744         mutex_unlock(&fsc->client->mount_mutex);
 745         return ERR_PTR(err);
 746
 747 fail:
 748         if (first) {
 749                 dput(fsc->sb->s_root);
 750                 fsc->sb->s_root = NULL;
 751         }
 752         goto out;
 753 }
 754
 755 static int ceph_set_super(struct super_block *s, void *data)
 756 {
 757         struct ceph_fs_client *fsc = data;
 758         int ret;
 759
 760         dout("set_super %p data %p\n", s, data);
 761
 762         s->s_flags = fsc->mount_options->sb_flags;
 763         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
 764
 765         s->s_fs_info = fsc;
 766         fsc->sb = s;
 767
 768         s->s_op = &ceph_super_ops;
 769         s->s_export_op = &ceph_export_ops;
 770
 771         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
 772
 773         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
 774         if (ret != 0)
 775                 goto fail;
 776
 777         return ret;
 778
 779 fail:
 780         s->s_fs_info = NULL;
 781         fsc->sb = NULL;
 782         return ret;
 783 }
 784
 785 /*
 786  * share superblock if same fs AND options
 787  */
 788 static int ceph_compare_super(struct super_block *sb, void *data)
 789 {
 790         struct ceph_fs_client *new = data;
 791         struct ceph_mount_options *fsopt = new->mount_options;
 792         struct ceph_options *opt = new->client->options;
 793         struct ceph_fs_client *other = ceph_sb_to_client(sb);
 794
 795         dout("ceph_compare_super %p\n", sb);
 796
 797         if (compare_mount_options(fsopt, opt, other)) {
 798                 dout("monitor(s)/mount options don't match\n");
 799                 return 0;
 800         }
 801         if ((opt->flags & CEPH_OPT_FSID) &&
 802             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
 803                 dout("fsid doesn't match\n");
 804                 return 0;
 805         }
 806         if (fsopt->sb_flags != other->mount_options->sb_flags) {
 807                 dout("flags differ\n");
 808                 return 0;
 809         }
 810         return 1;
 811 }
 812
 813 /*
 814  * construct our own bdi so we can control readahead, etc.
 815  */
 816 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
 817
 818 static int ceph_register_bdi(struct super_block *sb,
 819                              struct ceph_fs_client *fsc)
 820 {
 821         int err;
 822
 823         /* set ra_pages based on rasize mount option? */
 824         if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
 825                 fsc->backing_dev_info.ra_pages =
 826                         (fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
 827                         >> PAGE_SHIFT;
 828         else
 829                 fsc->backing_dev_info.ra_pages =
 830                         default_backing_dev_info.ra_pages;
 831
 832         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%d",
 833                            atomic_long_inc_return(&bdi_seq));
 834         if (!err)
 835                 sb->s_bdi = &fsc->backing_dev_info;
 836         return err;
 837 }
 838
 839 static struct dentry *ceph_mount(struct file_system_type *fs_type,
 840                        int flags, const char *dev_name, void *data)
 841 {
 842         struct super_block *sb;
 843         struct ceph_fs_client *fsc;
 844         struct dentry *res;
 845         int err;
 846         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
 847         const char *path = NULL;
 848         struct ceph_mount_options *fsopt = NULL;
 849         struct ceph_options *opt = NULL;
 850
 851         dout("ceph_mount\n");
 852         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
 853         if (err < 0) {
 854                 res = ERR_PTR(err);
 855                 goto out_final;
 856         }
 857
 858         /* create client (which we may/may not use) */
 859         fsc = create_fs_client(fsopt, opt);
 860         if (IS_ERR(fsc)) {
 861                 res = ERR_CAST(fsc);
 862                 destroy_mount_options(fsopt);
 863                 ceph_destroy_options(opt);
 864                 goto out_final;
 865         }
 866
 867         err = ceph_mdsc_init(fsc);
 868         if (err < 0) {
 869                 res = ERR_PTR(err);
 870                 goto out;
 871         }
 872
 873         if (ceph_test_opt(fsc->client, NOSHARE))
 874                 compare_super = NULL;
 875         sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
 876         if (IS_ERR(sb)) {
 877                 res = ERR_CAST(sb);
 878                 goto out;
 879         }
 880
 881         if (ceph_sb_to_client(sb) != fsc) {
 882                 ceph_mdsc_destroy(fsc);
 883                 destroy_fs_client(fsc);
 884                 fsc = ceph_sb_to_client(sb);
 885                 dout("get_sb got existing client %p\n", fsc);
 886         } else {
 887                 dout("get_sb using new client %p\n", fsc);
 888                 err = ceph_register_bdi(sb, fsc);
 889                 if (err < 0) {
 890                         res = ERR_PTR(err);
 891                         goto out_splat;
 892                 }
 893         }
 894
 895         res = ceph_real_mount(fsc, path);
 896         if (IS_ERR(res))
 897                 goto out_splat;
 898         dout("root %p inode %p ino %llx.%llx\n", res,
 899              res->d_inode, ceph_vinop(res->d_inode));
 900         return res;
 901
 902 out_splat:
 903         ceph_mdsc_close_sessions(fsc->mdsc);
 904         deactivate_locked_super(sb);
 905         goto out_final;
 906
 907 out:
 908         ceph_mdsc_destroy(fsc);
 909         destroy_fs_client(fsc);
 910 out_final:
 911         dout("ceph_mount fail %ld\n", PTR_ERR(res));
 912         return res;
 913 }
 914
 915 static void ceph_kill_sb(struct super_block *s)
 916 {
 917         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
 918         dout("kill_sb %p\n", s);
 919         ceph_mdsc_pre_umount(fsc->mdsc);
 920         kill_anon_super(s);    /* will call put_super after sb is r/o */
 921         ceph_mdsc_destroy(fsc);
 922         destroy_fs_client(fsc);
 923 }
 924
 925 static struct file_system_type ceph_fs_type = {
 926         .owner          = THIS_MODULE,
 927         .name           = "ceph",
 928         .mount          = ceph_mount,
 929         .kill_sb        = ceph_kill_sb,
 930         .fs_flags       = FS_RENAME_DOES_D_MOVE,
 931 };
 932
 933 #define _STRINGIFY(x) #x
 934 #define STRINGIFY(x) _STRINGIFY(x)
 935
 936 static int __init init_ceph(void)
 937 {
 938         int ret = init_caches();
 939         if (ret)
 940                 goto out;
 941
 942         ceph_xattr_init();
 943         ret = register_filesystem(&ceph_fs_type);
 944         if (ret)
 945                 goto out_icache;
 946
 947         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
 948
 949         return 0;
 950
 951 out_icache:
 952         ceph_xattr_exit();
 953         destroy_caches();
 954 out:
 955         return ret;
 956 }
 957
 958 static void __exit exit_ceph(void)
 959 {
 960         dout("exit_ceph\n");
 961         unregister_filesystem(&ceph_fs_type);
 962         ceph_xattr_exit();
 963         destroy_caches();
 964 }
 965
 966 module_init(init_ceph);
 967 module_exit(exit_ceph);
 968
 969 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
 970 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
 971 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
 972 MODULE_DESCRIPTION("Ceph filesystem for Linux");
 973 MODULE_LICENSE("GPL");