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