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 #include "cache.h"
  21
  22 #include <linux/ceph/ceph_features.h>
  23 #include <linux/ceph/decode.h>
  24 #include <linux/ceph/mon_client.h>
  25 #include <linux/ceph/auth.h>
  26 #include <linux/ceph/debugfs.h>
  27
  28 /*
  29  * Ceph superblock operations
  30  *
  31  * Handle the basics of mounting, unmounting.
  32  */
  33
  34 /*
  35  * super ops
  36  */
  37 static void ceph_put_super(struct super_block *s)
  38 {
  39         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
  40
  41         dout("put_super\n");
  42         ceph_mdsc_close_sessions(fsc->mdsc);
  43 }
  44
  45 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
  46 {
  47         struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
  48         struct ceph_monmap *monmap = fsc->client->monc.monmap;
  49         struct ceph_statfs st;
  50         u64 fsid;
  51         int err;
  52
  53         dout("statfs\n");
  54         err = ceph_monc_do_statfs(&fsc->client->monc, &st);
  55         if (err < 0)
  56                 return err;
  57
  58         /* fill in kstatfs */
  59         buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
  60
  61         /*
  62          * express utilization in terms of large blocks to avoid
  63          * overflow on 32-bit machines.
  64          *
  65          * NOTE: for the time being, we make bsize == frsize to humor
  66          * not-yet-ancient versions of glibc that are broken.
  67          * Someday, we will probably want to report a real block
  68          * size...  whatever that may mean for a network file system!
  69          */
  70         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
  71         buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
  72         buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
  73         buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  74         buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  75
  76         buf->f_files = le64_to_cpu(st.num_objects);
  77         buf->f_ffree = -1;
  78         buf->f_namelen = NAME_MAX;
  79
  80         /* leave fsid little-endian, regardless of host endianness */
  81         fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
  82         buf->f_fsid.val[0] = fsid & 0xffffffff;
  83         buf->f_fsid.val[1] = fsid >> 32;
  84
  85         return 0;
  86 }
  87
  88
  89 static int ceph_sync_fs(struct super_block *sb, int wait)
  90 {
  91         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
  92
  93         if (!wait) {
  94                 dout("sync_fs (non-blocking)\n");
  95                 ceph_flush_dirty_caps(fsc->mdsc);
  96                 dout("sync_fs (non-blocking) done\n");
  97                 return 0;
  98         }
  99
 100         dout("sync_fs (blocking)\n");
 101         ceph_osdc_sync(&fsc->client->osdc);
 102         ceph_mdsc_sync(fsc->mdsc);
 103         dout("sync_fs (blocking) done\n");
 104         return 0;
 105 }
 106
 107 /*
 108  * mount options
 109  */
 110 enum {
 111         Opt_wsize,
 112         Opt_rsize,
 113         Opt_rasize,
 114         Opt_caps_wanted_delay_min,
 115         Opt_caps_wanted_delay_max,
 116         Opt_cap_release_safety,
 117         Opt_readdir_max_entries,
 118         Opt_readdir_max_bytes,
 119         Opt_congestion_kb,
 120         Opt_last_int,
 121         /* int args above */
 122         Opt_snapdirname,
 123         Opt_last_string,
 124         /* string args above */
 125         Opt_dirstat,
 126         Opt_nodirstat,
 127         Opt_rbytes,
 128         Opt_norbytes,
 129         Opt_asyncreaddir,
 130         Opt_noasyncreaddir,
 131         Opt_dcache,
 132         Opt_nodcache,
 133         Opt_ino32,
 134         Opt_noino32,
 135         Opt_fscache,
 136         Opt_nofscache,
 137 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 138         Opt_acl,
 139 #endif
 140         Opt_noacl
 141 };
 142
 143 static match_table_t fsopt_tokens = {
 144         {Opt_wsize, "wsize=%d"},
 145         {Opt_rsize, "rsize=%d"},
 146         {Opt_rasize, "rasize=%d"},
 147         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
 148         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
 149         {Opt_cap_release_safety, "cap_release_safety=%d"},
 150         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
 151         {Opt_readdir_max_bytes, "readdir_max_bytes=%d"},
 152         {Opt_congestion_kb, "write_congestion_kb=%d"},
 153         /* int args above */
 154         {Opt_snapdirname, "snapdirname=%s"},
 155         /* string args above */
 156         {Opt_dirstat, "dirstat"},
 157         {Opt_nodirstat, "nodirstat"},
 158         {Opt_rbytes, "rbytes"},
 159         {Opt_norbytes, "norbytes"},
 160         {Opt_asyncreaddir, "asyncreaddir"},
 161         {Opt_noasyncreaddir, "noasyncreaddir"},
 162         {Opt_dcache, "dcache"},
 163         {Opt_nodcache, "nodcache"},
 164         {Opt_ino32, "ino32"},
 165         {Opt_noino32, "noino32"},
 166         {Opt_fscache, "fsc"},
 167         {Opt_nofscache, "nofsc"},
 168 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 169         {Opt_acl, "acl"},
 170 #endif
 171         {Opt_noacl, "noacl"},
 172         {-1, NULL}
 173 };
 174
 175 static int parse_fsopt_token(char *c, void *private)
 176 {
 177         struct ceph_mount_options *fsopt = private;
 178         substring_t argstr[MAX_OPT_ARGS];
 179         int token, intval, ret;
 180
 181         token = match_token((char *)c, fsopt_tokens, argstr);
 182         if (token < 0)
 183                 return -EINVAL;
 184
 185         if (token < Opt_last_int) {
 186                 ret = match_int(&argstr[0], &intval);
 187                 if (ret < 0) {
 188                         pr_err("bad mount option arg (not int) "
 189                                "at '%s'\n", c);
 190                         return ret;
 191                 }
 192                 dout("got int token %d val %d\n", token, intval);
 193         } else if (token > Opt_last_int && token < Opt_last_string) {
 194                 dout("got string token %d val %s\n", token,
 195                      argstr[0].from);
 196         } else {
 197                 dout("got token %d\n", token);
 198         }
 199
 200         switch (token) {
 201         case Opt_snapdirname:
 202                 kfree(fsopt->snapdir_name);
 203                 fsopt->snapdir_name = kstrndup(argstr[0].from,
 204                                                argstr[0].to-argstr[0].from,
 205                                                GFP_KERNEL);
 206                 if (!fsopt->snapdir_name)
 207                         return -ENOMEM;
 208                 break;
 209
 210                 /* misc */
 211         case Opt_wsize:
 212                 fsopt->wsize = intval;
 213                 break;
 214         case Opt_rsize:
 215                 fsopt->rsize = intval;
 216                 break;
 217         case Opt_rasize:
 218                 fsopt->rasize = intval;
 219                 break;
 220         case Opt_caps_wanted_delay_min:
 221                 fsopt->caps_wanted_delay_min = intval;
 222                 break;
 223         case Opt_caps_wanted_delay_max:
 224                 fsopt->caps_wanted_delay_max = intval;
 225                 break;
 226         case Opt_readdir_max_entries:
 227                 fsopt->max_readdir = intval;
 228                 break;
 229         case Opt_readdir_max_bytes:
 230                 fsopt->max_readdir_bytes = intval;
 231                 break;
 232         case Opt_congestion_kb:
 233                 fsopt->congestion_kb = intval;
 234                 break;
 235         case Opt_dirstat:
 236                 fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
 237                 break;
 238         case Opt_nodirstat:
 239                 fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
 240                 break;
 241         case Opt_rbytes:
 242                 fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
 243                 break;
 244         case Opt_norbytes:
 245                 fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
 246                 break;
 247         case Opt_asyncreaddir:
 248                 fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
 249                 break;
 250         case Opt_noasyncreaddir:
 251                 fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
 252                 break;
 253         case Opt_dcache:
 254                 fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
 255                 break;
 256         case Opt_nodcache:
 257                 fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
 258                 break;
 259         case Opt_ino32:
 260                 fsopt->flags |= CEPH_MOUNT_OPT_INO32;
 261                 break;
 262         case Opt_noino32:
 263                 fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
 264                 break;
 265         case Opt_fscache:
 266                 fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
 267                 break;
 268         case Opt_nofscache:
 269                 fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
 270                 break;
 271 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 272         case Opt_acl:
 273                 fsopt->sb_flags |= MS_POSIXACL;
 274                 break;
 275 #endif
 276         case Opt_noacl:
 277                 fsopt->sb_flags &= ~MS_POSIXACL;
 278                 break;
 279         default:
 280                 BUG_ON(token);
 281         }
 282         return 0;
 283 }
 284
 285 static void destroy_mount_options(struct ceph_mount_options *args)
 286 {
 287         dout("destroy_mount_options %p\n", args);
 288         kfree(args->snapdir_name);
 289         kfree(args);
 290 }
 291
 292 static int strcmp_null(const char *s1, const char *s2)
 293 {
 294         if (!s1 && !s2)
 295                 return 0;
 296         if (s1 && !s2)
 297                 return -1;
 298         if (!s1 && s2)
 299                 return 1;
 300         return strcmp(s1, s2);
 301 }
 302
 303 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
 304                                  struct ceph_options *new_opt,
 305                                  struct ceph_fs_client *fsc)
 306 {
 307         struct ceph_mount_options *fsopt1 = new_fsopt;
 308         struct ceph_mount_options *fsopt2 = fsc->mount_options;
 309         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
 310         int ret;
 311
 312         ret = memcmp(fsopt1, fsopt2, ofs);
 313         if (ret)
 314                 return ret;
 315
 316         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
 317         if (ret)
 318                 return ret;
 319
 320         return ceph_compare_options(new_opt, fsc->client);
 321 }
 322
 323 static int parse_mount_options(struct ceph_mount_options **pfsopt,
 324                                struct ceph_options **popt,
 325                                int flags, char *options,
 326                                const char *dev_name,
 327                                const char **path)
 328 {
 329         struct ceph_mount_options *fsopt;
 330         const char *dev_name_end;
 331         int err;
 332
 333         if (!dev_name || !*dev_name)
 334                 return -EINVAL;
 335
 336         fsopt = kzalloc(sizeof(*fsopt), GFP_KERNEL);
 337         if (!fsopt)
 338                 return -ENOMEM;
 339
 340         dout("parse_mount_options %p, dev_name '%s'\n", fsopt, dev_name);
 341
 342         fsopt->sb_flags = flags;
 343         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
 344
 345         fsopt->rsize = CEPH_RSIZE_DEFAULT;
 346         fsopt->rasize = CEPH_RASIZE_DEFAULT;
 347         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
 348         if (!fsopt->snapdir_name) {
 349                 err = -ENOMEM;
 350                 goto out;
 351         }
 352
 353         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
 354         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
 355         fsopt->cap_release_safety = CEPH_CAP_RELEASE_SAFETY_DEFAULT;
 356         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
 357         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
 358         fsopt->congestion_kb = default_congestion_kb();
 359
 360         /*
 361          * Distinguish the server list from the path in "dev_name".
 362          * Internally we do not include the leading '/' in the path.
 363          *
 364          * "dev_name" will look like:
 365          *     <server_spec>[,<server_spec>...]:[<path>]
 366          * where
 367          *     <server_spec> is <ip>[:<port>]
 368          *     <path> is optional, but if present must begin with '/'
 369          */
 370         dev_name_end = strchr(dev_name, '/');
 371         if (dev_name_end) {
 372                 /* skip over leading '/' for path */
 373                 *path = dev_name_end + 1;
 374         } else {
 375                 /* path is empty */
 376                 dev_name_end = dev_name + strlen(dev_name);
 377                 *path = dev_name_end;
 378         }
 379         err = -EINVAL;
 380         dev_name_end--;         /* back up to ':' separator */
 381         if (dev_name_end < dev_name || *dev_name_end != ':') {
 382                 pr_err("device name is missing path (no : separator in %s)\n",
 383                                 dev_name);
 384                 goto out;
 385         }
 386         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
 387         dout("server path '%s'\n", *path);
 388
 389         *popt = ceph_parse_options(options, dev_name, dev_name_end,
 390                                  parse_fsopt_token, (void *)fsopt);
 391         if (IS_ERR(*popt)) {
 392                 err = PTR_ERR(*popt);
 393                 goto out;
 394         }
 395
 396         /* success */
 397         *pfsopt = fsopt;
 398         return 0;
 399
 400 out:
 401         destroy_mount_options(fsopt);
 402         return err;
 403 }
 404
 405 /**
 406  * ceph_show_options - Show mount options in /proc/mounts
 407  * @m: seq_file to write to
 408  * @root: root of that (sub)tree
 409  */
 410 static int ceph_show_options(struct seq_file *m, struct dentry *root)
 411 {
 412         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
 413         struct ceph_mount_options *fsopt = fsc->mount_options;
 414         size_t pos;
 415         int ret;
 416
 417         /* a comma between MNT/MS and client options */
 418         seq_putc(m, ',');
 419         pos = m->count;
 420
 421         ret = ceph_print_client_options(m, fsc->client);
 422         if (ret)
 423                 return ret;
 424
 425         /* retract our comma if no client options */
 426         if (m->count == pos)
 427                 m->count--;
 428
 429         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
 430                 seq_puts(m, ",dirstat");
 431         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES) == 0)
 432                 seq_puts(m, ",norbytes");
 433         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
 434                 seq_puts(m, ",noasyncreaddir");
 435         if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
 436                 seq_puts(m, ",nodcache");
 437         if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE)
 438                 seq_puts(m, ",fsc");
 439
 440 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 441         if (fsopt->sb_flags & MS_POSIXACL)
 442                 seq_puts(m, ",acl");
 443         else
 444                 seq_puts(m, ",noacl");
 445 #endif
 446
 447         if (fsopt->wsize)
 448                 seq_printf(m, ",wsize=%d", fsopt->wsize);
 449         if (fsopt->rsize != CEPH_RSIZE_DEFAULT)
 450                 seq_printf(m, ",rsize=%d", fsopt->rsize);
 451         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
 452                 seq_printf(m, ",rasize=%d", fsopt->rasize);
 453         if (fsopt->congestion_kb != default_congestion_kb())
 454                 seq_printf(m, ",write_congestion_kb=%d", fsopt->congestion_kb);
 455         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
 456                 seq_printf(m, ",caps_wanted_delay_min=%d",
 457                          fsopt->caps_wanted_delay_min);
 458         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
 459                 seq_printf(m, ",caps_wanted_delay_max=%d",
 460                            fsopt->caps_wanted_delay_max);
 461         if (fsopt->cap_release_safety != CEPH_CAP_RELEASE_SAFETY_DEFAULT)
 462                 seq_printf(m, ",cap_release_safety=%d",
 463                            fsopt->cap_release_safety);
 464         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
 465                 seq_printf(m, ",readdir_max_entries=%d", fsopt->max_readdir);
 466         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
 467                 seq_printf(m, ",readdir_max_bytes=%d", fsopt->max_readdir_bytes);
 468         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 469                 seq_printf(m, ",snapdirname=%s", fsopt->snapdir_name);
 470
 471         return 0;
 472 }
 473
 474 /*
 475  * handle any mon messages the standard library doesn't understand.
 476  * return error if we don't either.
 477  */
 478 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
 479 {
 480         struct ceph_fs_client *fsc = client->private;
 481         int type = le16_to_cpu(msg->hdr.type);
 482
 483         switch (type) {
 484         case CEPH_MSG_MDS_MAP:
 485                 ceph_mdsc_handle_map(fsc->mdsc, msg);
 486                 return 0;
 487
 488         default:
 489                 return -1;
 490         }
 491 }
 492
 493 /*
 494  * create a new fs client
 495  */
 496 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 497                                         struct ceph_options *opt)
 498 {
 499         struct ceph_fs_client *fsc;
 500         const u64 supported_features =
 501                 CEPH_FEATURE_FLOCK |
 502                 CEPH_FEATURE_DIRLAYOUTHASH |
 503                 CEPH_FEATURE_MDS_INLINE_DATA;
 504         const u64 required_features = 0;
 505         int page_count;
 506         size_t size;
 507         int err = -ENOMEM;
 508
 509         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
 510         if (!fsc)
 511                 return ERR_PTR(-ENOMEM);
 512
 513         fsc->client = ceph_create_client(opt, fsc, supported_features,
 514                                          required_features);
 515         if (IS_ERR(fsc->client)) {
 516                 err = PTR_ERR(fsc->client);
 517                 goto fail;
 518         }
 519         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 520         fsc->client->monc.want_mdsmap = 1;
 521
 522         fsc->mount_options = fsopt;
 523
 524         fsc->sb = NULL;
 525         fsc->mount_state = CEPH_MOUNT_MOUNTING;
 526
 527         atomic_long_set(&fsc->writeback_count, 0);
 528
 529         err = bdi_init(&fsc->backing_dev_info);
 530         if (err < 0)
 531                 goto fail_client;
 532
 533         err = -ENOMEM;
 534         /*
 535          * The number of concurrent works can be high but they don't need
 536          * to be processed in parallel, limit concurrency.
 537          */
 538         fsc->wb_wq = alloc_workqueue("ceph-writeback", 0, 1);
 539         if (fsc->wb_wq == NULL)
 540                 goto fail_bdi;
 541         fsc->pg_inv_wq = alloc_workqueue("ceph-pg-invalid", 0, 1);
 542         if (fsc->pg_inv_wq == NULL)
 543                 goto fail_wb_wq;
 544         fsc->trunc_wq = alloc_workqueue("ceph-trunc", 0, 1);
 545         if (fsc->trunc_wq == NULL)
 546                 goto fail_pg_inv_wq;
 547
 548         /* set up mempools */
 549         err = -ENOMEM;
 550         page_count = fsc->mount_options->wsize >> PAGE_CACHE_SHIFT;
 551         size = sizeof (struct page *) * (page_count ? page_count : 1);
 552         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
 553         if (!fsc->wb_pagevec_pool)
 554                 goto fail_trunc_wq;
 555
 556         /* setup fscache */
 557         if ((fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) &&
 558             (ceph_fscache_register_fs(fsc) != 0))
 559                 goto fail_fscache;
 560
 561         /* caps */
 562         fsc->min_caps = fsopt->max_readdir;
 563
 564         return fsc;
 565
 566 fail_fscache:
 567         ceph_fscache_unregister_fs(fsc);
 568 fail_trunc_wq:
 569         destroy_workqueue(fsc->trunc_wq);
 570 fail_pg_inv_wq:
 571         destroy_workqueue(fsc->pg_inv_wq);
 572 fail_wb_wq:
 573         destroy_workqueue(fsc->wb_wq);
 574 fail_bdi:
 575         bdi_destroy(&fsc->backing_dev_info);
 576 fail_client:
 577         ceph_destroy_client(fsc->client);
 578 fail:
 579         kfree(fsc);
 580         return ERR_PTR(err);
 581 }
 582
 583 static void destroy_fs_client(struct ceph_fs_client *fsc)
 584 {
 585         dout("destroy_fs_client %p\n", fsc);
 586
 587         ceph_fscache_unregister_fs(fsc);
 588
 589         destroy_workqueue(fsc->wb_wq);
 590         destroy_workqueue(fsc->pg_inv_wq);
 591         destroy_workqueue(fsc->trunc_wq);
 592
 593         bdi_destroy(&fsc->backing_dev_info);
 594
 595         mempool_destroy(fsc->wb_pagevec_pool);
 596
 597         destroy_mount_options(fsc->mount_options);
 598
 599         ceph_fs_debugfs_cleanup(fsc);
 600
 601         ceph_destroy_client(fsc->client);
 602
 603         kfree(fsc);
 604         dout("destroy_fs_client %p done\n", fsc);
 605 }
 606
 607 /*
 608  * caches
 609  */
 610 struct kmem_cache *ceph_inode_cachep;
 611 struct kmem_cache *ceph_cap_cachep;
 612 struct kmem_cache *ceph_dentry_cachep;
 613 struct kmem_cache *ceph_file_cachep;
 614
 615 static void ceph_inode_init_once(void *foo)
 616 {
 617         struct ceph_inode_info *ci = foo;
 618         inode_init_once(&ci->vfs_inode);
 619 }
 620
 621 static int __init init_caches(void)
 622 {
 623         int error = -ENOMEM;
 624
 625         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 626                                       sizeof(struct ceph_inode_info),
 627                                       __alignof__(struct ceph_inode_info),
 628                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
 629                                       ceph_inode_init_once);
 630         if (ceph_inode_cachep == NULL)
 631                 return -ENOMEM;
 632
 633         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 634                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 635         if (ceph_cap_cachep == NULL)
 636                 goto bad_cap;
 637
 638         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 639                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 640         if (ceph_dentry_cachep == NULL)
 641                 goto bad_dentry;
 642
 643         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
 644                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 645         if (ceph_file_cachep == NULL)
 646                 goto bad_file;
 647
 648         if ((error = ceph_fscache_register()))
 649                 goto bad_file;
 650
 651         return 0;
 652 bad_file:
 653         kmem_cache_destroy(ceph_dentry_cachep);
 654 bad_dentry:
 655         kmem_cache_destroy(ceph_cap_cachep);
 656 bad_cap:
 657         kmem_cache_destroy(ceph_inode_cachep);
 658         return error;
 659 }
 660
 661 static void destroy_caches(void)
 662 {
 663         /*
 664          * Make sure all delayed rcu free inodes are flushed before we
 665          * destroy cache.
 666          */
 667         rcu_barrier();
 668
 669         kmem_cache_destroy(ceph_inode_cachep);
 670         kmem_cache_destroy(ceph_cap_cachep);
 671         kmem_cache_destroy(ceph_dentry_cachep);
 672         kmem_cache_destroy(ceph_file_cachep);
 673
 674         ceph_fscache_unregister();
 675 }
 676
 677
 678 /*
 679  * ceph_umount_begin - initiate forced umount.  Tear down down the
 680  * mount, skipping steps that may hang while waiting for server(s).
 681  */
 682 static void ceph_umount_begin(struct super_block *sb)
 683 {
 684         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 685
 686         dout("ceph_umount_begin - starting forced umount\n");
 687         if (!fsc)
 688                 return;
 689         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
 690         return;
 691 }
 692
 693 static const struct super_operations ceph_super_ops = {
 694         .alloc_inode    = ceph_alloc_inode,
 695         .destroy_inode  = ceph_destroy_inode,
 696         .write_inode    = ceph_write_inode,
 697         .drop_inode     = ceph_drop_inode,
 698         .sync_fs        = ceph_sync_fs,
 699         .put_super      = ceph_put_super,
 700         .show_options   = ceph_show_options,
 701         .statfs         = ceph_statfs,
 702         .umount_begin   = ceph_umount_begin,
 703 };
 704
 705 /*
 706  * Bootstrap mount by opening the root directory.  Note the mount
 707  * @started time from caller, and time out if this takes too long.
 708  */
 709 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 710                                        const char *path,
 711                                        unsigned long started)
 712 {
 713         struct ceph_mds_client *mdsc = fsc->mdsc;
 714         struct ceph_mds_request *req = NULL;
 715         int err;
 716         struct dentry *root;
 717
 718         /* open dir */
 719         dout("open_root_inode opening '%s'\n", path);
 720         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 721         if (IS_ERR(req))
 722                 return ERR_CAST(req);
 723         req->r_path1 = kstrdup(path, GFP_NOFS);
 724         if (!req->r_path1) {
 725                 root = ERR_PTR(-ENOMEM);
 726                 goto out;
 727         }
 728
 729         req->r_ino1.ino = CEPH_INO_ROOT;
 730         req->r_ino1.snap = CEPH_NOSNAP;
 731         req->r_started = started;
 732         req->r_timeout = fsc->client->options->mount_timeout * HZ;
 733         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 734         req->r_num_caps = 2;
 735         err = ceph_mdsc_do_request(mdsc, NULL, req);
 736         if (err == 0) {
 737                 struct inode *inode = req->r_target_inode;
 738                 req->r_target_inode = NULL;
 739                 dout("open_root_inode success\n");
 740                 if (ceph_ino(inode) == CEPH_INO_ROOT &&
 741                     fsc->sb->s_root == NULL) {
 742                         root = d_make_root(inode);
 743                         if (!root) {
 744                                 root = ERR_PTR(-ENOMEM);
 745                                 goto out;
 746                         }
 747                 } else {
 748                         root = d_obtain_root(inode);
 749                 }
 750                 ceph_init_dentry(root);
 751                 dout("open_root_inode success, root dentry is %p\n", root);
 752         } else {
 753                 root = ERR_PTR(err);
 754         }
 755 out:
 756         ceph_mdsc_put_request(req);
 757         return root;
 758 }
 759
 760
 761
 762
 763 /*
 764  * mount: join the ceph cluster, and open root directory.
 765  */
 766 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 767                       const char *path)
 768 {
 769         int err;
 770         unsigned long started = jiffies;  /* note the start time */
 771         struct dentry *root;
 772         int first = 0;   /* first vfsmount for this super_block */
 773
 774         dout("mount start\n");
 775         mutex_lock(&fsc->client->mount_mutex);
 776
 777         err = __ceph_open_session(fsc->client, started);
 778         if (err < 0)
 779                 goto out;
 780
 781         dout("mount opening root\n");
 782         root = open_root_dentry(fsc, "", started);
 783         if (IS_ERR(root)) {
 784                 err = PTR_ERR(root);
 785                 goto out;
 786         }
 787         if (fsc->sb->s_root) {
 788                 dput(root);
 789         } else {
 790                 fsc->sb->s_root = root;
 791                 first = 1;
 792
 793                 err = ceph_fs_debugfs_init(fsc);
 794                 if (err < 0)
 795                         goto fail;
 796         }
 797
 798         if (path[0] == 0) {
 799                 dget(root);
 800         } else {
 801                 dout("mount opening base mountpoint\n");
 802                 root = open_root_dentry(fsc, path, started);
 803                 if (IS_ERR(root)) {
 804                         err = PTR_ERR(root);
 805                         goto fail;
 806                 }
 807         }
 808
 809         fsc->mount_state = CEPH_MOUNT_MOUNTED;
 810         dout("mount success\n");
 811         mutex_unlock(&fsc->client->mount_mutex);
 812         return root;
 813
 814 out:
 815         mutex_unlock(&fsc->client->mount_mutex);
 816         return ERR_PTR(err);
 817
 818 fail:
 819         if (first) {
 820                 dput(fsc->sb->s_root);
 821                 fsc->sb->s_root = NULL;
 822         }
 823         goto out;
 824 }
 825
 826 static int ceph_set_super(struct super_block *s, void *data)
 827 {
 828         struct ceph_fs_client *fsc = data;
 829         int ret;
 830
 831         dout("set_super %p data %p\n", s, data);
 832
 833         s->s_flags = fsc->mount_options->sb_flags;
 834         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
 835
 836         s->s_xattr = ceph_xattr_handlers;
 837         s->s_fs_info = fsc;
 838         fsc->sb = s;
 839
 840         s->s_op = &ceph_super_ops;
 841         s->s_export_op = &ceph_export_ops;
 842
 843         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
 844
 845         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
 846         if (ret != 0)
 847                 goto fail;
 848
 849         return ret;
 850
 851 fail:
 852         s->s_fs_info = NULL;
 853         fsc->sb = NULL;
 854         return ret;
 855 }
 856
 857 /*
 858  * share superblock if same fs AND options
 859  */
 860 static int ceph_compare_super(struct super_block *sb, void *data)
 861 {
 862         struct ceph_fs_client *new = data;
 863         struct ceph_mount_options *fsopt = new->mount_options;
 864         struct ceph_options *opt = new->client->options;
 865         struct ceph_fs_client *other = ceph_sb_to_client(sb);
 866
 867         dout("ceph_compare_super %p\n", sb);
 868
 869         if (compare_mount_options(fsopt, opt, other)) {
 870                 dout("monitor(s)/mount options don't match\n");
 871                 return 0;
 872         }
 873         if ((opt->flags & CEPH_OPT_FSID) &&
 874             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
 875                 dout("fsid doesn't match\n");
 876                 return 0;
 877         }
 878         if (fsopt->sb_flags != other->mount_options->sb_flags) {
 879                 dout("flags differ\n");
 880                 return 0;
 881         }
 882         return 1;
 883 }
 884
 885 /*
 886  * construct our own bdi so we can control readahead, etc.
 887  */
 888 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
 889
 890 static int ceph_register_bdi(struct super_block *sb,
 891                              struct ceph_fs_client *fsc)
 892 {
 893         int err;
 894
 895         /* set ra_pages based on rasize mount option? */
 896         if (fsc->mount_options->rasize >= PAGE_CACHE_SIZE)
 897                 fsc->backing_dev_info.ra_pages =
 898                         (fsc->mount_options->rasize + PAGE_CACHE_SIZE - 1)
 899                         >> PAGE_SHIFT;
 900         else
 901                 fsc->backing_dev_info.ra_pages =
 902                         VM_MAX_READAHEAD * 1024 / PAGE_CACHE_SIZE;
 903
 904         err = bdi_register(&fsc->backing_dev_info, NULL, "ceph-%ld",
 905                            atomic_long_inc_return(&bdi_seq));
 906         if (!err)
 907                 sb->s_bdi = &fsc->backing_dev_info;
 908         return err;
 909 }
 910
 911 static struct dentry *ceph_mount(struct file_system_type *fs_type,
 912                        int flags, const char *dev_name, void *data)
 913 {
 914         struct super_block *sb;
 915         struct ceph_fs_client *fsc;
 916         struct dentry *res;
 917         int err;
 918         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
 919         const char *path = NULL;
 920         struct ceph_mount_options *fsopt = NULL;
 921         struct ceph_options *opt = NULL;
 922
 923         dout("ceph_mount\n");
 924
 925 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 926         flags |= MS_POSIXACL;
 927 #endif
 928         err = parse_mount_options(&fsopt, &opt, flags, data, dev_name, &path);
 929         if (err < 0) {
 930                 res = ERR_PTR(err);
 931                 goto out_final;
 932         }
 933
 934         /* create client (which we may/may not use) */
 935         fsc = create_fs_client(fsopt, opt);
 936         if (IS_ERR(fsc)) {
 937                 res = ERR_CAST(fsc);
 938                 destroy_mount_options(fsopt);
 939                 ceph_destroy_options(opt);
 940                 goto out_final;
 941         }
 942
 943         err = ceph_mdsc_init(fsc);
 944         if (err < 0) {
 945                 res = ERR_PTR(err);
 946                 goto out;
 947         }
 948
 949         if (ceph_test_opt(fsc->client, NOSHARE))
 950                 compare_super = NULL;
 951         sb = sget(fs_type, compare_super, ceph_set_super, flags, fsc);
 952         if (IS_ERR(sb)) {
 953                 res = ERR_CAST(sb);
 954                 goto out;
 955         }
 956
 957         if (ceph_sb_to_client(sb) != fsc) {
 958                 ceph_mdsc_destroy(fsc);
 959                 destroy_fs_client(fsc);
 960                 fsc = ceph_sb_to_client(sb);
 961                 dout("get_sb got existing client %p\n", fsc);
 962         } else {
 963                 dout("get_sb using new client %p\n", fsc);
 964                 err = ceph_register_bdi(sb, fsc);
 965                 if (err < 0) {
 966                         res = ERR_PTR(err);
 967                         goto out_splat;
 968                 }
 969         }
 970
 971         res = ceph_real_mount(fsc, path);
 972         if (IS_ERR(res))
 973                 goto out_splat;
 974         dout("root %p inode %p ino %llx.%llx\n", res,
 975              d_inode(res), ceph_vinop(d_inode(res)));
 976         return res;
 977
 978 out_splat:
 979         ceph_mdsc_close_sessions(fsc->mdsc);
 980         deactivate_locked_super(sb);
 981         goto out_final;
 982
 983 out:
 984         ceph_mdsc_destroy(fsc);
 985         destroy_fs_client(fsc);
 986 out_final:
 987         dout("ceph_mount fail %ld\n", PTR_ERR(res));
 988         return res;
 989 }
 990
 991 static void ceph_kill_sb(struct super_block *s)
 992 {
 993         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
 994         dev_t dev = s->s_dev;
 995
 996         dout("kill_sb %p\n", s);
 997
 998         ceph_mdsc_pre_umount(fsc->mdsc);
 999         generic_shutdown_super(s);
1000         ceph_mdsc_destroy(fsc);
1001
1002         destroy_fs_client(fsc);
1003         free_anon_bdev(dev);
1004 }
1005
1006 static struct file_system_type ceph_fs_type = {
1007         .owner          = THIS_MODULE,
1008         .name           = "ceph",
1009         .mount          = ceph_mount,
1010         .kill_sb        = ceph_kill_sb,
1011         .fs_flags       = FS_RENAME_DOES_D_MOVE,
1012 };
1013 MODULE_ALIAS_FS("ceph");
1014
1015 static int __init init_ceph(void)
1016 {
1017         int ret = init_caches();
1018         if (ret)
1019                 goto out;
1020
1021         ceph_flock_init();
1022         ceph_xattr_init();
1023         ret = ceph_snap_init();
1024         if (ret)
1025                 goto out_xattr;
1026         ret = register_filesystem(&ceph_fs_type);
1027         if (ret)
1028                 goto out_snap;
1029
1030         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1031
1032         return 0;
1033
1034 out_snap:
1035         ceph_snap_exit();
1036 out_xattr:
1037         ceph_xattr_exit();
1038         destroy_caches();
1039 out:
1040         return ret;
1041 }
1042
1043 static void __exit exit_ceph(void)
1044 {
1045         dout("exit_ceph\n");
1046         unregister_filesystem(&ceph_fs_type);
1047         ceph_snap_exit();
1048         ceph_xattr_exit();
1049         destroy_caches();
1050 }
1051
1052 module_init(init_ceph);
1053 module_exit(exit_ceph);
1054
1055 MODULE_AUTHOR("Sage Weil <[email protected]>");
1056 MODULE_AUTHOR("Yehuda Sadeh <[email protected]>");
1057 MODULE_AUTHOR("Patience Warnick <[email protected]>");
1058 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1059 MODULE_LICENSE("GPL");