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