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;
 311
 312         if (!dev_name || !*dev_name)
 313                 return -EINVAL;
 314
 315         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
 316         if (!fsopt)
 317                 return -ENOMEM;
 318
 319         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
 320
 321         fsopt->sb_flags = flags;
 322         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
 323
 324         fsopt->rsize = CEPH_RSIZE_DEFAULT;
 325         fsopt->rasize = CEPH_RASIZE_DEFAULT;
 326         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
 327         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
 328         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
 329         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
 330         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
 331         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
 332         fsopt->congestion_kb = default_congestion_kb();
 333
 334         /*
 335          * Distinguish the server list from the path in "dev_name".
 336          * Internally we do not include the leading '/' in the path.
 337          *
 338          * "dev_name" will look like:
 339          *     <server_spec>[,<server_spec>...]:[<path>]
 340          * where
 341          *     <server_spec> is <ip>[:<port>]
 342          *     <path> is optional, but if present must begin with '/'
 343          */
 344         dev_name_end = strchr(dev_name, '/');
 345         if (dev_name_end) {
 346                 /* skip over leading '/' for path */
 347                 *path = dev_name_end + 1;
 348         } else {
 349                 /* path is empty */
 350                 dev_name_end = dev_name + strlen(dev_name);
 351                 *path = dev_name_end;
 352         }
 353         err = -EINVAL;
 354         dev_name_end--;         /* back up to ':' separator */
 355         if (*dev_name_end != ':') {
 356                 pr_err("device name is missing path (no : separator in %s)\n",
 357                                 dev_name);
 358                 goto out;
 359         }
 360         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
 361         dout("server path '%s'\n", *path);
 362
 363         *popt = ceph_parse_options(options, dev_name, dev_name_end,
 364                                  parse_fsopt_token, (void *)fsopt);
 365         if (IS_ERR(*popt)) {
 366                 err = PTR_ERR(*popt);
 367                 goto out;
 368         }
 369
 370         /* success */
 371         *pfsopt = fsopt;
 372         return 0;
 373
 374 out:
 375         destroy_mount_options(fsopt);
 376         return err;
 377 }
 378
 379 /**
 380  * ceph_show_options - Show mount options in /proc/mounts
 381  * @m: seq_file to write to
 382  * @root: root of that (sub)tree
 383  */
 384 static int ceph_show_options(struct seq_file *m, struct dentry *root)
 385 {
 386         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
 387         struct ceph_mount_options *fsopt = fsc->mount_options;
 388         struct ceph_options *opt = fsc->client->options;
 389
 390         if (opt->flags & CEPH_OPT_FSID)
 391                 seq_printf(m, ",fsid=%pU", &opt->fsid);
 392         if (opt->flags & CEPH_OPT_NOSHARE)
 393                 seq_puts(m, ",noshare");
 394         if (opt->flags & CEPH_OPT_NOCRC)
 395                 seq_puts(m, ",nocrc");
 396
 397         if (opt->name)
 398                 seq_printf(m, ",name=%s", opt->name);
 399         if (opt->key)
 400                 seq_puts(m, ",secret=<hidden>");
 401
 402         if (opt->mount_timeout != CEPH_MOUNT_TIMEOUT_DEFAULT)
 403                 seq_printf(m, ",mount_timeout=%d", opt->mount_timeout);
 404         if (opt->osd_idle_ttl != CEPH_OSD_IDLE_TTL_DEFAULT)
 405                 seq_printf(m, ",osd_idle_ttl=%d", opt->osd_idle_ttl);
 406         if (opt->osd_keepalive_timeout != CEPH_OSD_KEEPALIVE_DEFAULT)
 407                 seq_printf(m, ",osdkeepalivetimeout=%d",
 408                            opt->osd_keepalive_timeout);
 409
 410         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
 411                 seq_puts(m, ",dirstat");
 412         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
 413                 seq_puts(m, ",norbytes");
 414         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
 415                 seq_puts(m, ",noasyncreaddir");
 416         if (fsopt->flags & CEPH_MOUNT_OPT_DCACHE)
 417                 seq_puts(m, ",dcache");
 418         else
 419                 seq_puts(m, ",nodcache");
 420
 421         if (fsopt->wsize)
 422                 seq_printf(m, ",wsize=%d", fsopt->wsize);
 423         if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
 424                 seq_printf(m, ",rsize=%d", fsopt->rsize);
 425         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
 426                 seq_printf(m, ",rasize=%d", fsopt->rasize);
 427         if (fsopt->congestion_kb != default_congestion_kb())
 428                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
 429         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
 430                 seq_printf(m, ",caps_wanted_delay_min=%d",
 431                          fsopt->caps_wanted_delay_min);
 432         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
 433                 seq_printf(m, ",caps_wanted_delay_max=%d",
 434                            fsopt->caps_wanted_delay_max);
 435         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
 436                 seq_printf(m, ",cap_release_safety=%d",
 437                            fsopt->cap_release_safety);
 438         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
 439                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
 440         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
 441                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
 442         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 443                 seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
 444         return 0;
 445 }
 446
 447 /*
 448  * handle any mon messages the standard library doesn't understand.
 449  * return error if we don't either.
 450  */
 451 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
 452 {
 453         struct ceph_fs_client *fsc = client->private;
 454         int type = le16_to_cpu(msg->hdr.type);
 455
 456         switch (type) {
 457         case CEPH_MSG_MDS_MAP:
 458                 ceph_mdsc_handle_map(fsc->mdsc, msg);
 459                 return 0;
 460
 461         default:
 462                 return -1;
 463         }
 464 }
 465
 466 /*
 467  * create a new fs client
 468  */
 469 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 470                                         struct ceph_options *opt)
 471 {
 472         struct ceph_fs_client *fsc;
 473         const unsigned supported_features =
 474                 CEPH_FEATURE_FLOCK |
 475                 CEPH_FEATURE_DIRLAYOUTHASH;
 476         const unsigned required_features = 0;
 477         int err = -ENOMEM;
 478
 479         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
 480         if (!fsc)
 481                 return ERR_PTR(-ENOMEM);
 482
 483         fsc->client = ceph_create_client(opt, fsc, supported_features,
 484                                          required_features);
 485         if (IS_ERR(fsc->client)) {
 486                 err = PTR_ERR(fsc->client);
 487                 goto fail;
 488         }
 489         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 490         fsc->client->monc.want_mdsmap = 1;
 491
 492         fsc->mount_options = fsopt;
 493
 494         fsc->sb = NULL;
 495         fsc->mount_state = CEPH_MOUNT_MOUNTING;
 496
 497         atomic_long_set(&fsc->writeback_count, 0);
 498
 499         err = bdi_init(&fsc->backing_dev_info);
 500         if (err < 0)
 501                 goto fail_client;
 502
 503         err = -ENOMEM;
 504         /*
 505          * The number of concurrent works can be high but they don't need
 506          * to be processed in parallel, limit concurrency.
 507          */
 508         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
 509         if (fsc->wb_wq == NULL)
 510                 goto fail_bdi;
 511         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
 512         if (fsc->pg_inv_wq == NULL)
 513                 goto fail_wb_wq;
 514         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
 515         if (fsc->trunc_wq == NULL)
 516                 goto fail_pg_inv_wq;
 517
 518         /* set up mempools */
 519         err = -ENOMEM;
 520         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
 521                               fsc->mount_options->wsize >> PAGE_CACHE_SHIFT);
 522         if (!fsc->wb_pagevec_pool)
 523                 goto fail_trunc_wq;
 524
 525         /* caps */
 526         fsc->min_caps = fsopt->max_readdir;
 527
 528         return fsc;
 529
 530 fail_trunc_wq:
 531         destroy_workqueue(fsc->trunc_wq);
 532 fail_pg_inv_wq:
 533         destroy_workqueue(fsc->pg_inv_wq);
 534 fail_wb_wq:
 535         destroy_workqueue(fsc->wb_wq);
 536 fail_bdi:
 537         bdi_destroy(&fsc->backing_dev_info);
 538 fail_client:
 539         ceph_destroy_client(fsc->client);
 540 fail:
 541         kfree(fsc);
 542         return ERR_PTR(err);
 543 }
 544
 545 static void destroy_fs_client(struct ceph_fs_client *fsc)
 546 {
 547         dout("destroy_fs_client %p\n", fsc);
 548
 549         destroy_workqueue(fsc->wb_wq);
 550         destroy_workqueue(fsc->pg_inv_wq);
 551         destroy_workqueue(fsc->trunc_wq);
 552
 553         bdi_destroy(&fsc->backing_dev_info);
 554
 555         mempool_destroy(fsc->wb_pagevec_pool);
 556
 557         destroy_mount_options(fsc->mount_options);
 558
 559         ceph_fs_debugfs_cleanup(fsc);
 560
 561         ceph_destroy_client(fsc->client);
 562
 563         kfree(fsc);
 564         dout("destroy_fs_client %p done\n", fsc);
 565 }
 566
 567 /*
 568  * caches
 569  */
 570 struct kmem_cache *ceph_inode_cachep;
 571 struct kmem_cache *ceph_cap_cachep;
 572 struct kmem_cache *ceph_dentry_cachep;
 573 struct kmem_cache *ceph_file_cachep;
 574
 575 static void ceph_inode_init_once(void *foo)
 576 {
 577         struct ceph_inode_info *ci = foo;
 578         inode_init_once(&ci->vfs_inode);
 579 }
 580
 581 static int __init init_caches(void)
 582 {
 583         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 584                                       sizeof(struct ceph_inode_info),
 585                                       __alignof__(struct ceph_inode_info),
 586                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
 587                                       ceph_inode_init_once);
 588         if (ceph_inode_cachep == NULL)
 589                 return -ENOMEM;
 590
 591         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 592                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 593         if (ceph_cap_cachep == NULL)
 594                 goto bad_cap;
 595
 596         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 597                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 598         if (ceph_dentry_cachep == NULL)
 599                 goto bad_dentry;
 600
 601         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
 602                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 603         if (ceph_file_cachep == NULL)
 604                 goto bad_file;
 605
 606         return 0;
 607
 608 bad_file:
 609         kmem_cache_destroy(ceph_dentry_cachep);
 610 bad_dentry:
 611         kmem_cache_destroy(ceph_cap_cachep);
 612 bad_cap:
 613         kmem_cache_destroy(ceph_inode_cachep);
 614         return -ENOMEM;
 615 }
 616
 617 static void destroy_caches(void)
 618 {
 619         kmem_cache_destroy(ceph_inode_cachep);
 620         kmem_cache_destroy(ceph_cap_cachep);
 621         kmem_cache_destroy(ceph_dentry_cachep);
 622         kmem_cache_destroy(ceph_file_cachep);
 623 }
 624
 625
 626 /*
 627  * ceph_umount_begin - initiate forced umount.  Tear down down the
 628  * mount, skipping steps that may hang while waiting for server(s).
 629  */
 630 static void ceph_umount_begin(struct super_block *sb)
 631 {
 632         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 633
 634         dout("ceph_umount_begin - starting forced umount\n");
 635         if (!fsc)
 636                 return;
 637         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
 638         return;
 639 }
 640
 641 static const struct super_operations ceph_super_ops = {
 642         .alloc_inode    = ceph_alloc_inode,
 643         .destroy_inode  = ceph_destroy_inode,
 644         .write_inode    = ceph_write_inode,
 645         .sync_fs        = ceph_sync_fs,
 646         .put_super      = ceph_put_super,
 647         .show_options   = ceph_show_options,
 648         .statfs         = ceph_statfs,
 649         .umount_begin   = ceph_umount_begin,
 650 };
 651
 652 /*
 653  * Bootstrap mount by opening the root directory.  Note the mount
 654  * @started time from caller, and time out if this takes too long.
 655  */
 656 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 657                                        const char *path,
 658                                        unsigned long started)
 659 {
 660         struct ceph_mds_client *mdsc = fsc->mdsc;
 661         struct ceph_mds_request *req = NULL;
 662         int err;
 663         struct dentry *root;
 664
 665         /* open dir */
 666         dout("open_root_inode opening '%s'\n", path);
 667         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 668         if (IS_ERR(req))
 669                 return ERR_CAST(req);
 670         req->r_path1 = kstrdup(path, GFP_NOFS);
 671         req->r_ino1.ino = CEPH_INO_ROOT;
 672         req->r_ino1.snap = CEPH_NOSNAP;
 673         req->r_started = started;
 674         req->r_timeout = fsc->client->options->mount_timeout * HZ;
 675         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 676         req->r_num_caps = 2;
 677         err = ceph_mdsc_do_request(mdsc, NULL, req);
 678         if (err == 0) {
 679                 struct inode *inode = req->r_target_inode;
 680                 req->r_target_inode = NULL;
 681                 dout("open_root_inode success\n");
 682                 if (ceph_ino(inode) == CEPH_INO_ROOT &&
 683                     fsc->sb->s_root == NULL) {
 684                         root = d_make_root(inode);
 685                         if (!root) {
 686                                 root = ERR_PTR(-ENOMEM);
 687                                 goto out;
 688                         }
 689                 } else {
 690                         root = d_obtain_alias(inode);
 691                 }
 692                 ceph_init_dentry(root);
 693                 dout("open_root_inode success, root dentry is %p\n", root);
 694         } else {
 695                 root = ERR_PTR(err);
 696         }
 697 out:
 698         ceph_mdsc_put_request(req);
 699         return root;
 700 }
 701
 702
 703
 704
 705 /*
 706  * mount: join the ceph cluster, and open root directory.
 707  */
 708 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 709                       const char *path)
 710 {
 711         int err;
 712         unsigned long started = jiffies;  /* note the start time */
 713         struct dentry *root;
 714         int first = 0;   /* first vfsmount for this super_block */
 715
 716         dout("mount start\n");
 717         mutex_lock(&fsc->client->mount_mutex);
 718
 719         err = __ceph_open_session(fsc->client, started);
 720         if (err < 0)
 721                 goto out;
 722
 723         dout("mount opening root\n");
 724         root = open_root_dentry(fsc, "", started);
 725         if (IS_ERR(root)) {
 726                 err = PTR_ERR(root);
 727                 goto out;
 728         }
 729         if (fsc->sb->s_root) {
 730                 dput(root);
 731         } else {
 732                 fsc->sb->s_root = root;
 733                 first = 1;
 734
 735                 err = ceph_fs_debugfs_init(fsc);
 736                 if (err < 0)
 737                         goto fail;
 738         }
 739
 740         if (path[0] == 0) {
 741                 dget(root);
 742         } else {
 743                 dout("mount opening base mountpoint\n");
 744                 root = open_root_dentry(fsc, path, started);
 745                 if (IS_ERR(root)) {
 746                         err = PTR_ERR(root);
 747                         goto fail;
 748                 }
 749         }
 750
 751         fsc->mount_state = CEPH_MOUNT_MOUNTED;
 752         dout("mount success\n");
 753         mutex_unlock(&fsc->client->mount_mutex);
 754         return root;
 755
 756 out:
 757         mutex_unlock(&fsc->client->mount_mutex);
 758         return ERR_PTR(err);
 759
 760 fail:
 761         if (first) {
 762                 dput(fsc->sb->s_root);
 763                 fsc->sb->s_root = NULL;
 764         }
 765         goto out;
 766 }
 767
 768 static int ceph_set_super(struct super_block *s, void *data)
 769 {
 770         struct ceph_fs_client *fsc = data;
 771         int ret;
 772
 773         dout("set_super %p data %p\n", s, data);
 774
 775         s->s_flags = fsc->mount_options->sb_flags;
 776         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
 777
 778         s->s_fs_info = fsc;
 779         fsc->sb = s;
 780
 781         s->s_op = &ceph_super_ops;
 782         s->s_export_op = &ceph_export_ops;
 783
 784         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
 785
 786         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
 787         if (ret != 0)
 788                 goto fail;
 789
 790         return ret;
 791
 792 fail:
 793         s->s_fs_info = NULL;
 794         fsc->sb = NULL;
 795         return ret;
 796 }
 797
 798 /*
 799  * share superblock if same fs AND options
 800  */
 801 static int ceph_compare_super(struct super_block *sb, void *data)
 802 {
 803         struct ceph_fs_client *new = data;
 804         struct ceph_mount_options *fsopt = new->mount_options;
 805         struct ceph_options *opt = new->client->options;
 806         struct ceph_fs_client *other = ceph_sb_to_client(sb);
 807
 808         dout("ceph_compare_super %p\n", sb);
 809
 810         if (compare_mount_options(fsopt, opt, other)) {
 811                 dout("monitor(s)/mount options don't match\n");
 812                 return 0;
 813         }
 814         if ((opt->flags & CEPH_OPT_FSID) &&
 815             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
 816                 dout("fsid doesn't match\n");
 817                 return 0;
 818         }
 819         if (fsopt->sb_flags != other->mount_options->sb_flags) {
 820                 dout("flags differ\n");
 821                 return 0;
 822         }
 823         return 1;
 824 }
 825
 826 /*
 827  * construct our own bdi so we can control readahead, etc.
 828  */
 829 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
 830
 831 static int ceph_register_bdi(struct super_block *sb,
 832                              struct ceph_fs_client *fsc)
 833 {
 834         int err;
 835
 836         /* set ra_pages based on rasize mount option? */
 837         if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
 838                 fsc->backing_dev_info.ra_pages =
 839                         (fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
 840                         >> PAGE_SHIFT;
 841         else
 842                 fsc->backing_dev_info.ra_pages =
 843                         default_backing_dev_info.ra_pages;
 844
 845         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld",
 846                            atomic_long_inc_return(&bdi_seq));
 847         if (!err)
 848                 sb->s_bdi = &fsc->backing_dev_info;
 849         return err;
 850 }
 851
 852 static struct dentry *ceph_mount(struct file_system_type *fs_type,
 853                        int flags, const char *dev_name, void *data)
 854 {
 855         struct super_block *sb;
 856         struct ceph_fs_client *fsc;
 857         struct dentry *res;
 858         int err;
 859         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
 860         const char *path = NULL;
 861         struct ceph_mount_options *fsopt = NULL;
 862         struct ceph_options *opt = NULL;
 863
 864         dout("ceph_mount\n");
 865         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
 866         if (err < 0) {
 867                 res = ERR_PTR(err);
 868                 goto out_final;
 869         }
 870
 871         /* create client (which we may/may not use) */
 872         fsc = create_fs_client(fsopt, opt);
 873         if (IS_ERR(fsc)) {
 874                 res = ERR_CAST(fsc);
 875                 destroy_mount_options(fsopt);
 876                 ceph_destroy_options(opt);
 877                 goto out_final;
 878         }
 879
 880         err = ceph_mdsc_init(fsc);
 881         if (err < 0) {
 882                 res = ERR_PTR(err);
 883                 goto out;
 884         }
 885
 886         if (ceph_test_opt(fsc->client, NOSHARE))
 887                 compare_super = NULL;
 888         sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
 889         if (IS_ERR(sb)) {
 890                 res = ERR_CAST(sb);
 891                 goto out;
 892         }
 893
 894         if (ceph_sb_to_client(sb) != fsc) {
 895                 ceph_mdsc_destroy(fsc);
 896                 destroy_fs_client(fsc);
 897                 fsc = ceph_sb_to_client(sb);
 898                 dout("get_sb got existing client %p\n", fsc);
 899         } else {
 900                 dout("get_sb using new client %p\n", fsc);
 901                 err = ceph_register_bdi(sb, fsc);
 902                 if (err < 0) {
 903                         res = ERR_PTR(err);
 904                         goto out_splat;
 905                 }
 906         }
 907
 908         res = ceph_real_mount(fsc, path);
 909         if (IS_ERR(res))
 910                 goto out_splat;
 911         dout("root %p inode %p ino %llx.%llx\n", res,
 912              res->d_inode, ceph_vinop(res->d_inode));
 913         return res;
 914
 915 out_splat:
 916         ceph_mdsc_close_sessions(fsc->mdsc);
 917         deactivate_locked_super(sb);
 918         goto out_final;
 919
 920 out:
 921         ceph_mdsc_destroy(fsc);
 922         destroy_fs_client(fsc);
 923 out_final:
 924         dout("ceph_mount fail %ld\n", PTR_ERR(res));
 925         return res;
 926 }
 927
 928 static void ceph_kill_sb(struct super_block *s)
 929 {
 930         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
 931         dout("kill_sb %p\n", s);
 932         ceph_mdsc_pre_umount(fsc->mdsc);
 933         kill_anon_super(s);    /* will call put_super after sb is r/o */
 934         ceph_mdsc_destroy(fsc);
 935         destroy_fs_client(fsc);
 936 }
 937
 938 static struct file_system_type ceph_fs_type = {
 939         .owner          = THIS_MODULE,
 940         .name           = "ceph",
 941         .mount          = ceph_mount,
 942         .kill_sb        = ceph_kill_sb,
 943         .fs_flags       = FS_RENAME_DOES_D_MOVE,
 944 };
 945
 946 #define _STRINGIFY(x) #x
 947 #define STRINGIFY(x) _STRINGIFY(x)
 948
 949 static int __init init_ceph(void)
 950 {
 951         int ret = init_caches();
 952         if (ret)
 953                 goto out;
 954
 955         ceph_xattr_init();
 956         ret = register_filesystem(&ceph_fs_type);
 957         if (ret)
 958                 goto out_icache;
 959
 960         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
 961
 962         return 0;
 963
 964 out_icache:
 965         ceph_xattr_exit();
 966         destroy_caches();
 967 out:
 968         return ret;
 969 }
 970
 971 static void __exit exit_ceph(void)
 972 {
 973         dout("exit_ceph\n");
 974         unregister_filesystem(&ceph_fs_type);
 975         ceph_xattr_exit();
 976         destroy_caches();
 977 }
 978
 979 module_init(init_ceph);
 980 module_exit(exit_ceph);
 981
 982 MODULE_AUTHOR("Sage Weil <[email protected]>");
 983 MODULE_AUTHOR("Yehuda Sadeh <[email protected]>");
 984 MODULE_AUTHOR("Patience Warnick <[email protected]>");
 985 MODULE_DESCRIPTION("Ceph filesystem for Linux");
 986 MODULE_LICENSE("GPL");