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          * NOTE: for the time being, we make bsize == frsize to humor
  76          * not-yet-ancient versions of glibc that are broken.
  77          * Someday, we will probably want to report a real block
  78          * size...  whatever that may mean for a network file system!
  79          */
  80         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
  81         buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
  82         buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
  83         buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  84         buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  85
  86         buf->f_files = le64_to_cpu(st.num_objects);
  87         buf->f_ffree = -1;
  88         buf->f_namelen = NAME_MAX;
  89
  90         /* leave fsid little-endian, regardless of host endianness */
  91         fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
  92         buf->f_fsid.val[0] = fsid & 0xffffffff;
  93         buf->f_fsid.val[1] = fsid >> 32;
  94
  95         return 0;
  96 }
  97
  98
  99 static int ceph_sync_fs(struct super_block *sb, int wait)
 100 {
 101         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 102
 103         if (!wait) {
 104                 dout("sync_fs (non-blocking)\n");
 105                 ceph_flush_dirty_caps(fsc->mdsc);
 106                 dout("sync_fs (non-blocking) done\n");
 107                 return 0;
 108         }
 109
 110         dout("sync_fs (blocking)\n");
 111         ceph_osdc_sync(&fsc->client->osdc);
 112         ceph_mdsc_sync(fsc->mdsc);
 113         dout("sync_fs (blocking) done\n");
 114         return 0;
 115 }
 116
 117 /*
 118  * mount options
 119  */
 120 enum {
 121         Opt_wsize,
 122         Opt_rsize,
 123         Opt_rasize,
 124         Opt_caps_wanted_delay_min,
 125         Opt_caps_wanted_delay_max,
 126         Opt_cap_release_safety,
 127         Opt_readdir_max_entries,
 128         Opt_readdir_max_bytes,
 129         Opt_congestion_kb,
 130         Opt_last_int,
 131         /* int args above */
 132         Opt_snapdirname,
 133         Opt_last_string,
 134         /* string args above */
 135         Opt_dirstat,
 136         Opt_nodirstat,
 137         Opt_rbytes,
 138         Opt_norbytes,
 139         Opt_asyncreaddir,
 140         Opt_noasyncreaddir,
 141         Opt_dcache,
 142         Opt_nodcache,
 143         Opt_ino32,
 144         Opt_noino32,
 145 };
 146
 147 static match_table_t fsopt_tokens = {
 148         {Opt_wsize, "wsize=%d"},
 149         {Opt_rsize, "rsize=%d"},
 150         {Opt_rasize, "rasize=%d"},
 151         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
 152         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
 153         {Opt_cap_release_safety, "cap_release_safety=%d"},
 154         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
 155         {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
 156         {Opt_congestion_kb, "write_congestion_kb=%d"},
 157         /* int args above */
 158         {Opt_snapdirname, "snapdirname=%s"},
 159         /* string args above */
 160         {Opt_dirstat, "dirstat"},
 161         {Opt_nodirstat, "nodirstat"},
 162         {Opt_rbytes, "rbytes"},
 163         {Opt_norbytes, "norbytes"},
 164         {Opt_asyncreaddir, "asyncreaddir"},
 165         {Opt_noasyncreaddir, "noasyncreaddir"},
 166         {Opt_dcache, "dcache"},
 167         {Opt_nodcache, "nodcache"},
 168         {Opt_ino32, "ino32"},
 169         {Opt_noino32, "noino32"},
 170         {-1, NULL}
 171 };
 172
 173 static int parse_fsopt_token(char *c, void *private)
 174 {
 175         struct ceph_mount_options *fsopt = private;
 176         substring_t argstr[MAX_OPT_ARGS];
 177         int token, intval, ret;
 178
 179         token = match_token((char *)c, fsopt_tokens, argstr);
 180         if (token < 0)
 181                 return -EINVAL;
 182
 183         if (token < Opt_last_int) {
 184                 ret = match_int(&argstr[0], &intval);
 185                 if (ret < 0) {
 186                         pr_err("bad mount option arg (not int) "
 187                                "at '%s'\n", c);
 188                         return ret;
 189                 }
 190                 dout("got int token %d val %d\n", token, intval);
 191         } else if (token > Opt_last_int && token < Opt_last_string) {
 192                 dout("got string token %d val %s\n", token,
 193                      argstr[0].from);
 194         } else {
 195                 dout("got token %d\n", token);
 196         }
 197
 198         switch (token) {
 199         case Opt_snapdirname:
 200                 kfree(fsopt->snapdir_name);
 201                 fsopt->snapdir_name = kstrndup(argstr[0].from,
 202                                                argstr[0].to-argstr[0].from,
 203                                                GFP_KERNEL);
 204                 if (!fsopt->snapdir_name)
 205                         return -ENOMEM;
 206                 break;
 207
 208                 /* misc */
 209         case Opt_wsize:
 210                 fsopt->wsize = intval;
 211                 break;
 212         case Opt_rsize:
 213                 fsopt->rsize = intval;
 214                 break;
 215         case Opt_rasize:
 216                 fsopt->rasize = intval;
 217                 break;
 218         case Opt_caps_wanted_delay_min:
 219                 fsopt->caps_wanted_delay_min = intval;
 220                 break;
 221         case Opt_caps_wanted_delay_max:
 222                 fsopt->caps_wanted_delay_max = intval;
 223                 break;
 224         case Opt_readdir_max_entries:
 225                 fsopt->max_readdir = intval;
 226                 break;
 227         case Opt_readdir_max_bytes:
 228                 fsopt->max_readdir_bytes = intval;
 229                 break;
 230         case Opt_congestion_kb:
 231                 fsopt->congestion_kb = intval;
 232                 break;
 233         case Opt_dirstat:
 234                 fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
 235                 break;
 236         case Opt_nodirstat:
 237                 fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
 238                 break;
 239         case Opt_rbytes:
 240                 fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
 241                 break;
 242         case Opt_norbytes:
 243                 fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
 244                 break;
 245         case Opt_asyncreaddir:
 246                 fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
 247                 break;
 248         case Opt_noasyncreaddir:
 249                 fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
 250                 break;
 251         case Opt_dcache:
 252                 fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
 253                 break;
 254         case Opt_nodcache:
 255                 fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
 256                 break;
 257         case Opt_ino32:
 258                 fsopt->flags |= CEPH_MOUNT_OPT_INO32;
 259                 break;
 260         case Opt_noino32:
 261                 fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
 262                 break;
 263         default:
 264                 BUG_ON(token);
 265         }
 266         return 0;
 267 }
 268
 269 static void destroy_mount_options(struct ceph_mount_options *args)
 270 {
 271         dout("destroy_mount_options %p\n", args);
 272         kfree(args->snapdir_name);
 273         kfree(args);
 274 }
 275
 276 static int strcmp_null(const char *s1, const char *s2)
 277 {
 278         if (!s1 && !s2)
 279                 return 0;
 280         if (s1 && !s2)
 281                 return -1;
 282         if (!s1 && s2)
 283                 return 1;
 284         return strcmp(s1, s2);
 285 }
 286
 287 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
 288                                  struct ceph_options *new_opt,
 289                                  struct ceph_fs_client *fsc)
 290 {
 291         struct ceph_mount_options *fsopt1 = new_fsopt;
 292         struct ceph_mount_options *fsopt2 = fsc->mount_options;
 293         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
 294         int ret;
 295
 296         ret = memcmp(fsopt1, fsopt2, ofs);
 297         if (ret)
 298                 return ret;
 299
 300         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
 301         if (ret)
 302                 return ret;
 303
 304         return ceph_compare_options(new_opt, fsc->client);
 305 }
 306
 307 static int parse_mount_options(struct ceph_mount_options **pfsopt,
 308                                struct ceph_options **popt,
 309                                int flags, char *options,
 310                                const char *dev_name,
 311                                const char **path)
 312 {
 313         struct ceph_mount_options *fsopt;
 314         const char *dev_name_end;
 315         int err;
 316
 317         if (!dev_name || !*dev_name)
 318                 return -EINVAL;
 319
 320         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
 321         if (!fsopt)
 322                 return -ENOMEM;
 323
 324         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
 325
 326         fsopt->sb_flags = flags;
 327         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
 328
 329         fsopt->rsize = CEPH_RSIZE_DEFAULT;
 330         fsopt->rasize = CEPH_RASIZE_DEFAULT;
 331         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
 332         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
 333         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
 334         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
 335         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
 336         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
 337         fsopt->congestion_kb = default_congestion_kb();
 338
 339         /*
 340          * Distinguish the server list from the path in "dev_name".
 341          * Internally we do not include the leading '/' in the path.
 342          *
 343          * "dev_name" will look like:
 344          *     <server_spec>[,<server_spec>...]:[<path>]
 345          * where
 346          *     <server_spec> is <ip>[:<port>]
 347          *     <path> is optional, but if present must begin with '/'
 348          */
 349         dev_name_end = strchr(dev_name, '/');
 350         if (dev_name_end) {
 351                 /* skip over leading '/' for path */
 352                 *path = dev_name_end + 1;
 353         } else {
 354                 /* path is empty */
 355                 dev_name_end = dev_name + strlen(dev_name);
 356                 *path = dev_name_end;
 357         }
 358         err = -EINVAL;
 359         dev_name_end--;         /* back up to ':' separator */
 360         if (*dev_name_end != ':') {
 361                 pr_err("device name is missing path (no : separator in %s)\n",
 362                                 dev_name);
 363                 goto out;
 364         }
 365         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
 366         dout("server path '%s'\n", *path);
 367
 368         *popt = ceph_parse_options(options, dev_name, dev_name_end,
 369                                  parse_fsopt_token, (void *)fsopt);
 370         if (IS_ERR(*popt)) {
 371                 err = PTR_ERR(*popt);
 372                 goto out;
 373         }
 374
 375         /* success */
 376         *pfsopt = fsopt;
 377         return 0;
 378
 379 out:
 380         destroy_mount_options(fsopt);
 381         return err;
 382 }
 383
 384 /**
 385  * ceph_show_options - Show mount options in /proc/mounts
 386  * @m: seq_file to write to
 387  * @root: root of that (sub)tree
 388  */
 389 static int ceph_show_options(struct seq_file *m, struct dentry *root)
 390 {
 391         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
 392         struct ceph_mount_options *fsopt = fsc->mount_options;
 393         struct ceph_options *opt = fsc->client->options;
 394
 395         if (opt->flags & CEPH_OPT_FSID)
 396                 seq_printf(m, ",fsid=%pU", &opt->fsid);
 397         if (opt->flags & CEPH_OPT_NOSHARE)
 398                 seq_puts(m, ",noshare");
 399         if (opt->flags & CEPH_OPT_NOCRC)
 400                 seq_puts(m, ",nocrc");
 401
 402         if (opt->name)
 403                 seq_printf(m, ",name=%s", opt->name);
 404         if (opt->key)
 405                 seq_puts(m, ",secret=<hidden>");
 406
 407         if (opt->mount_timeout != CEPH_MOUNT_TIMEOUT_DEFAULT)
 408                 seq_printf(m, ",mount_timeout=%d", opt->mount_timeout);
 409         if (opt->osd_idle_ttl != CEPH_OSD_IDLE_TTL_DEFAULT)
 410                 seq_printf(m, ",osd_idle_ttl=%d", opt->osd_idle_ttl);
 411         if (opt->osd_keepalive_timeout != CEPH_OSD_KEEPALIVE_DEFAULT)
 412                 seq_printf(m, ",osdkeepalivetimeout=%d",
 413                            opt->osd_keepalive_timeout);
 414
 415         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
 416                 seq_puts(m, ",dirstat");
 417         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
 418                 seq_puts(m, ",norbytes");
 419         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
 420                 seq_puts(m, ",noasyncreaddir");
 421         if (fsopt->flags & CEPH_MOUNT_OPT_DCACHE)
 422                 seq_puts(m, ",dcache");
 423         else
 424                 seq_puts(m, ",nodcache");
 425
 426         if (fsopt->wsize)
 427                 seq_printf(m, ",wsize=%d", fsopt->wsize);
 428         if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
 429                 seq_printf(m, ",rsize=%d", fsopt->rsize);
 430         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
 431                 seq_printf(m, ",rasize=%d", fsopt->rasize);
 432         if (fsopt->congestion_kb != default_congestion_kb())
 433                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
 434         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
 435                 seq_printf(m, ",caps_wanted_delay_min=%d",
 436                          fsopt->caps_wanted_delay_min);
 437         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
 438                 seq_printf(m, ",caps_wanted_delay_max=%d",
 439                            fsopt->caps_wanted_delay_max);
 440         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
 441                 seq_printf(m, ",cap_release_safety=%d",
 442                            fsopt->cap_release_safety);
 443         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
 444                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
 445         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
 446                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
 447         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 448                 seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
 449         return 0;
 450 }
 451
 452 /*
 453  * handle any mon messages the standard library doesn't understand.
 454  * return error if we don't either.
 455  */
 456 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
 457 {
 458         struct ceph_fs_client *fsc = client->private;
 459         int type = le16_to_cpu(msg->hdr.type);
 460
 461         switch (type) {
 462         case CEPH_MSG_MDS_MAP:
 463                 ceph_mdsc_handle_map(fsc->mdsc, msg);
 464                 return 0;
 465
 466         default:
 467                 return -1;
 468         }
 469 }
 470
 471 /*
 472  * create a new fs client
 473  */
 474 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 475                                         struct ceph_options *opt)
 476 {
 477         struct ceph_fs_client *fsc;
 478         const unsigned supported_features =
 479                 CEPH_FEATURE_FLOCK |
 480                 CEPH_FEATURE_DIRLAYOUTHASH;
 481         const unsigned required_features = 0;
 482         int err = -ENOMEM;
 483
 484         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
 485         if (!fsc)
 486                 return ERR_PTR(-ENOMEM);
 487
 488         fsc->client = ceph_create_client(opt, fsc, supported_features,
 489                                          required_features);
 490         if (IS_ERR(fsc->client)) {
 491                 err = PTR_ERR(fsc->client);
 492                 goto fail;
 493         }
 494         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 495         fsc->client->monc.want_mdsmap = 1;
 496
 497         fsc->mount_options = fsopt;
 498
 499         fsc->sb = NULL;
 500         fsc->mount_state = CEPH_MOUNT_MOUNTING;
 501
 502         atomic_long_set(&fsc->writeback_count, 0);
 503
 504         err = bdi_init(&fsc->backing_dev_info);
 505         if (err < 0)
 506                 goto fail_client;
 507
 508         err = -ENOMEM;
 509         /*
 510          * The number of concurrent works can be high but they don't need
 511          * to be processed in parallel, limit concurrency.
 512          */
 513         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
 514         if (fsc->wb_wq == NULL)
 515                 goto fail_bdi;
 516         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
 517         if (fsc->pg_inv_wq == NULL)
 518                 goto fail_wb_wq;
 519         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
 520         if (fsc->trunc_wq == NULL)
 521                 goto fail_pg_inv_wq;
 522
 523         /* set up mempools */
 524         err = -ENOMEM;
 525         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
 526                               fsc->mount_options->wsize >> PAGE_CACHE_SHIFT);
 527         if (!fsc->wb_pagevec_pool)
 528                 goto fail_trunc_wq;
 529
 530         /* caps */
 531         fsc->min_caps = fsopt->max_readdir;
 532
 533         return fsc;
 534
 535 fail_trunc_wq:
 536         destroy_workqueue(fsc->trunc_wq);
 537 fail_pg_inv_wq:
 538         destroy_workqueue(fsc->pg_inv_wq);
 539 fail_wb_wq:
 540         destroy_workqueue(fsc->wb_wq);
 541 fail_bdi:
 542         bdi_destroy(&fsc->backing_dev_info);
 543 fail_client:
 544         ceph_destroy_client(fsc->client);
 545 fail:
 546         kfree(fsc);
 547         return ERR_PTR(err);
 548 }
 549
 550 static void destroy_fs_client(struct ceph_fs_client *fsc)
 551 {
 552         dout("destroy_fs_client %p\n", fsc);
 553
 554         destroy_workqueue(fsc->wb_wq);
 555         destroy_workqueue(fsc->pg_inv_wq);
 556         destroy_workqueue(fsc->trunc_wq);
 557
 558         bdi_destroy(&fsc->backing_dev_info);
 559
 560         mempool_destroy(fsc->wb_pagevec_pool);
 561
 562         destroy_mount_options(fsc->mount_options);
 563
 564         ceph_fs_debugfs_cleanup(fsc);
 565
 566         ceph_destroy_client(fsc->client);
 567
 568         kfree(fsc);
 569         dout("destroy_fs_client %p done\n", fsc);
 570 }
 571
 572 /*
 573  * caches
 574  */
 575 struct kmem_cache *ceph_inode_cachep;
 576 struct kmem_cache *ceph_cap_cachep;
 577 struct kmem_cache *ceph_dentry_cachep;
 578 struct kmem_cache *ceph_file_cachep;
 579
 580 static void ceph_inode_init_once(void *foo)
 581 {
 582         struct ceph_inode_info *ci = foo;
 583         inode_init_once(&ci->vfs_inode);
 584 }
 585
 586 static int __init init_caches(void)
 587 {
 588         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 589                                       sizeof(struct ceph_inode_info),
 590                                       __alignof__(struct ceph_inode_info),
 591                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
 592                                       ceph_inode_init_once);
 593         if (ceph_inode_cachep == NULL)
 594                 return -ENOMEM;
 595
 596         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 597                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 598         if (ceph_cap_cachep == NULL)
 599                 goto bad_cap;
 600
 601         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 602                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 603         if (ceph_dentry_cachep == NULL)
 604                 goto bad_dentry;
 605
 606         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
 607                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 608         if (ceph_file_cachep == NULL)
 609                 goto bad_file;
 610
 611         return 0;
 612
 613 bad_file:
 614         kmem_cache_destroy(ceph_dentry_cachep);
 615 bad_dentry:
 616         kmem_cache_destroy(ceph_cap_cachep);
 617 bad_cap:
 618         kmem_cache_destroy(ceph_inode_cachep);
 619         return -ENOMEM;
 620 }
 621
 622 static void destroy_caches(void)
 623 {
 624         /*
 625          * Make sure all delayed rcu free inodes are flushed before we
 626          * destroy cache.
 627          */
 628         rcu_barrier();
 629         kmem_cache_destroy(ceph_inode_cachep);
 630         kmem_cache_destroy(ceph_cap_cachep);
 631         kmem_cache_destroy(ceph_dentry_cachep);
 632         kmem_cache_destroy(ceph_file_cachep);
 633 }
 634
 635
 636 /*
 637  * ceph_umount_begin - initiate forced umount.  Tear down down the
 638  * mount, skipping steps that may hang while waiting for server(s).
 639  */
 640 static void ceph_umount_begin(struct super_block *sb)
 641 {
 642         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 643
 644         dout("ceph_umount_begin - starting forced umount\n");
 645         if (!fsc)
 646                 return;
 647         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
 648         return;
 649 }
 650
 651 static const struct super_operations ceph_super_ops = {
 652         .alloc_inode    = ceph_alloc_inode,
 653         .destroy_inode  = ceph_destroy_inode,
 654         .write_inode    = ceph_write_inode,
 655         .sync_fs        = ceph_sync_fs,
 656         .put_super      = ceph_put_super,
 657         .show_options   = ceph_show_options,
 658         .statfs         = ceph_statfs,
 659         .umount_begin   = ceph_umount_begin,
 660 };
 661
 662 /*
 663  * Bootstrap mount by opening the root directory.  Note the mount
 664  * @started time from caller, and time out if this takes too long.
 665  */
 666 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 667                                        const char *path,
 668                                        unsigned long started)
 669 {
 670         struct ceph_mds_client *mdsc = fsc->mdsc;
 671         struct ceph_mds_request *req = NULL;
 672         int err;
 673         struct dentry *root;
 674
 675         /* open dir */
 676         dout("open_root_inode opening '%s'\n", path);
 677         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 678         if (IS_ERR(req))
 679                 return ERR_CAST(req);
 680         req->r_path1 = kstrdup(path, GFP_NOFS);
 681         req->r_ino1.ino = CEPH_INO_ROOT;
 682         req->r_ino1.snap = CEPH_NOSNAP;
 683         req->r_started = started;
 684         req->r_timeout = fsc->client->options->mount_timeout * HZ;
 685         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 686         req->r_num_caps = 2;
 687         err = ceph_mdsc_do_request(mdsc, NULL, req);
 688         if (err == 0) {
 689                 struct inode *inode = req->r_target_inode;
 690                 req->r_target_inode = NULL;
 691                 dout("open_root_inode success\n");
 692                 if (ceph_ino(inode) == CEPH_INO_ROOT &&
 693                     fsc->sb->s_root == NULL) {
 694                         root = d_make_root(inode);
 695                         if (!root) {
 696                                 root = ERR_PTR(-ENOMEM);
 697                                 goto out;
 698                         }
 699                 } else {
 700                         root = d_obtain_alias(inode);
 701                 }
 702                 ceph_init_dentry(root);
 703                 dout("open_root_inode success, root dentry is %p\n", root);
 704         } else {
 705                 root = ERR_PTR(err);
 706         }
 707 out:
 708         ceph_mdsc_put_request(req);
 709         return root;
 710 }
 711
 712
 713
 714
 715 /*
 716  * mount: join the ceph cluster, and open root directory.
 717  */
 718 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 719                       const char *path)
 720 {
 721         int err;
 722         unsigned long started = jiffies;  /* note the start time */
 723         struct dentry *root;
 724         int first = 0;   /* first vfsmount for this super_block */
 725
 726         dout("mount start\n");
 727         mutex_lock(&fsc->client->mount_mutex);
 728
 729         err = __ceph_open_session(fsc->client, started);
 730         if (err < 0)
 731                 goto out;
 732
 733         dout("mount opening root\n");
 734         root = open_root_dentry(fsc, "", started);
 735         if (IS_ERR(root)) {
 736                 err = PTR_ERR(root);
 737                 goto out;
 738         }
 739         if (fsc->sb->s_root) {
 740                 dput(root);
 741         } else {
 742                 fsc->sb->s_root = root;
 743                 first = 1;
 744
 745                 err = ceph_fs_debugfs_init(fsc);
 746                 if (err < 0)
 747                         goto fail;
 748         }
 749
 750         if (path[0] == 0) {
 751                 dget(root);
 752         } else {
 753                 dout("mount opening base mountpoint\n");
 754                 root = open_root_dentry(fsc, path, started);
 755                 if (IS_ERR(root)) {
 756                         err = PTR_ERR(root);
 757                         goto fail;
 758                 }
 759         }
 760
 761         fsc->mount_state = CEPH_MOUNT_MOUNTED;
 762         dout("mount success\n");
 763         mutex_unlock(&fsc->client->mount_mutex);
 764         return root;
 765
 766 out:
 767         mutex_unlock(&fsc->client->mount_mutex);
 768         return ERR_PTR(err);
 769
 770 fail:
 771         if (first) {
 772                 dput(fsc->sb->s_root);
 773                 fsc->sb->s_root = NULL;
 774         }
 775         goto out;
 776 }
 777
 778 static int ceph_set_super(struct super_block *s, void *data)
 779 {
 780         struct ceph_fs_client *fsc = data;
 781         int ret;
 782
 783         dout("set_super %p data %p\n", s, data);
 784
 785         s->s_flags = fsc->mount_options->sb_flags;
 786         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
 787
 788         s->s_fs_info = fsc;
 789         fsc->sb = s;
 790
 791         s->s_op = &ceph_super_ops;
 792         s->s_export_op = &ceph_export_ops;
 793
 794         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
 795
 796         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
 797         if (ret != 0)
 798                 goto fail;
 799
 800         return ret;
 801
 802 fail:
 803         s->s_fs_info = NULL;
 804         fsc->sb = NULL;
 805         return ret;
 806 }
 807
 808 /*
 809  * share superblock if same fs AND options
 810  */
 811 static int ceph_compare_super(struct super_block *sb, void *data)
 812 {
 813         struct ceph_fs_client *new = data;
 814         struct ceph_mount_options *fsopt = new->mount_options;
 815         struct ceph_options *opt = new->client->options;
 816         struct ceph_fs_client *other = ceph_sb_to_client(sb);
 817
 818         dout("ceph_compare_super %p\n", sb);
 819
 820         if (compare_mount_options(fsopt, opt, other)) {
 821                 dout("monitor(s)/mount options don't match\n");
 822                 return 0;
 823         }
 824         if ((opt->flags & CEPH_OPT_FSID) &&
 825             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
 826                 dout("fsid doesn't match\n");
 827                 return 0;
 828         }
 829         if (fsopt->sb_flags != other->mount_options->sb_flags) {
 830                 dout("flags differ\n");
 831                 return 0;
 832         }
 833         return 1;
 834 }
 835
 836 /*
 837  * construct our own bdi so we can control readahead, etc.
 838  */
 839 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
 840
 841 static int ceph_register_bdi(struct super_block *sb,
 842                              struct ceph_fs_client *fsc)
 843 {
 844         int err;
 845
 846         /* set ra_pages based on rasize mount option? */
 847         if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
 848                 fsc->backing_dev_info.ra_pages =
 849                         (fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
 850                         >> PAGE_SHIFT;
 851         else
 852                 fsc->backing_dev_info.ra_pages =
 853                         default_backing_dev_info.ra_pages;
 854
 855         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld",
 856                            atomic_long_inc_return(&bdi_seq));
 857         if (!err)
 858                 sb->s_bdi = &fsc->backing_dev_info;
 859         return err;
 860 }
 861
 862 static struct dentry *ceph_mount(struct file_system_type *fs_type,
 863                        int flags, const char *dev_name, void *data)
 864 {
 865         struct super_block *sb;
 866         struct ceph_fs_client *fsc;
 867         struct dentry *res;
 868         int err;
 869         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
 870         const char *path = NULL;
 871         struct ceph_mount_options *fsopt = NULL;
 872         struct ceph_options *opt = NULL;
 873
 874         dout("ceph_mount\n");
 875         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
 876         if (err < 0) {
 877                 res = ERR_PTR(err);
 878                 goto out_final;
 879         }
 880
 881         /* create client (which we may/may not use) */
 882         fsc = create_fs_client(fsopt, opt);
 883         if (IS_ERR(fsc)) {
 884                 res = ERR_CAST(fsc);
 885                 destroy_mount_options(fsopt);
 886                 ceph_destroy_options(opt);
 887                 goto out_final;
 888         }
 889
 890         err = ceph_mdsc_init(fsc);
 891         if (err < 0) {
 892                 res = ERR_PTR(err);
 893                 goto out;
 894         }
 895
 896         if (ceph_test_opt(fsc->client, NOSHARE))
 897                 compare_super = NULL;
 898         sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
 899         if (IS_ERR(sb)) {
 900                 res = ERR_CAST(sb);
 901                 goto out;
 902         }
 903
 904         if (ceph_sb_to_client(sb) != fsc) {
 905                 ceph_mdsc_destroy(fsc);
 906                 destroy_fs_client(fsc);
 907                 fsc = ceph_sb_to_client(sb);
 908                 dout("get_sb got existing client %p\n", fsc);
 909         } else {
 910                 dout("get_sb using new client %p\n", fsc);
 911                 err = ceph_register_bdi(sb, fsc);
 912                 if (err < 0) {
 913                         res = ERR_PTR(err);
 914                         goto out_splat;
 915                 }
 916         }
 917
 918         res = ceph_real_mount(fsc, path);
 919         if (IS_ERR(res))
 920                 goto out_splat;
 921         dout("root %p inode %p ino %llx.%llx\n", res,
 922              res->d_inode, ceph_vinop(res->d_inode));
 923         return res;
 924
 925 out_splat:
 926         ceph_mdsc_close_sessions(fsc->mdsc);
 927         deactivate_locked_super(sb);
 928         goto out_final;
 929
 930 out:
 931         ceph_mdsc_destroy(fsc);
 932         destroy_fs_client(fsc);
 933 out_final:
 934         dout("ceph_mount fail %ld\n", PTR_ERR(res));
 935         return res;
 936 }
 937
 938 static void ceph_kill_sb(struct super_block *s)
 939 {
 940         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
 941         dout("kill_sb %p\n", s);
 942         ceph_mdsc_pre_umount(fsc->mdsc);
 943         kill_anon_super(s);    /* will call put_super after sb is r/o */
 944         ceph_mdsc_destroy(fsc);
 945         destroy_fs_client(fsc);
 946 }
 947
 948 static struct file_system_type ceph_fs_type = {
 949         .owner          = THIS_MODULE,
 950         .name           = "ceph",
 951         .mount          = ceph_mount,
 952         .kill_sb        = ceph_kill_sb,
 953         .fs_flags       = FS_RENAME_DOES_D_MOVE,
 954 };
 955
 956 #define _STRINGIFY(x) #x
 957 #define STRINGIFY(x) _STRINGIFY(x)
 958
 959 static int __init init_ceph(void)
 960 {
 961         int ret = init_caches();
 962         if (ret)
 963                 goto out;
 964
 965         ceph_xattr_init();
 966         ret = register_filesystem(&ceph_fs_type);
 967         if (ret)
 968                 goto out_icache;
 969
 970         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
 971
 972         return 0;
 973
 974 out_icache:
 975         ceph_xattr_exit();
 976         destroy_caches();
 977 out:
 978         return ret;
 979 }
 980
 981 static void __exit exit_ceph(void)
 982 {
 983         dout("exit_ceph\n");
 984         unregister_filesystem(&ceph_fs_type);
 985         ceph_xattr_exit();
 986         destroy_caches();
 987 }
 988
 989 module_init(init_ceph);
 990 module_exit(exit_ceph);
 991
 992 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
 993 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
 994 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
 995 MODULE_DESCRIPTION("Ceph filesystem for Linux");
 996 MODULE_LICENSE("GPL");