fs/ceph/super.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <linux/ceph/ceph_debug.h>
   4
   5 #include <linux/backing-dev.h>
   6 #include <linux/ctype.h>
   7 #include <linux/fs.h>
   8 #include <linux/inet.h>
   9 #include <linux/in6.h>
  10 #include <linux/module.h>
  11 #include <linux/mount.h>
  12 #include <linux/fs_context.h>
  13 #include <linux/fs_parser.h>
  14 #include <linux/sched.h>
  15 #include <linux/seq_file.h>
  16 #include <linux/slab.h>
  17 #include <linux/statfs.h>
  18 #include <linux/string.h>
  19
  20 #include "super.h"
  21 #include "mds_client.h"
  22 #include "cache.h"
  23
  24 #include <linux/ceph/ceph_features.h>
  25 #include <linux/ceph/decode.h>
  26 #include <linux/ceph/mon_client.h>
  27 #include <linux/ceph/auth.h>
  28 #include <linux/ceph/debugfs.h>
  29
  30 /*
  31  * Ceph superblock operations
  32  *
  33  * Handle the basics of mounting, unmounting.
  34  */
  35
  36 /*
  37  * super ops
  38  */
  39 static void ceph_put_super(struct super_block *s)
  40 {
  41         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
  42
  43         dout("put_super\n");
  44         ceph_mdsc_close_sessions(fsc->mdsc);
  45 }
  46
  47 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
  48 {
  49         struct ceph_fs_client *fsc = ceph_inode_to_client(d_inode(dentry));
  50         struct ceph_mon_client *monc = &fsc->client->monc;
  51         struct ceph_statfs st;
  52         u64 fsid;
  53         int err;
  54         u64 data_pool;
  55
  56         if (fsc->mdsc->mdsmap->m_num_data_pg_pools == 1) {
  57                 data_pool = fsc->mdsc->mdsmap->m_data_pg_pools[0];
  58         } else {
  59                 data_pool = CEPH_NOPOOL;
  60         }
  61
  62         dout("statfs\n");
  63         err = ceph_monc_do_statfs(monc, data_pool, &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          * NOTE: for the time being, we make bsize == frsize to humor
  75          * not-yet-ancient versions of glibc that are broken.
  76          * Someday, we will probably want to report a real block
  77          * size...  whatever that may mean for a network file system!
  78          */
  79         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
  80         buf->f_frsize = 1 << CEPH_BLOCK_SHIFT;
  81
  82         /*
  83          * By default use root quota for stats; fallback to overall filesystem
  84          * usage if using 'noquotadf' mount option or if the root dir doesn't
  85          * have max_bytes quota set.
  86          */
  87         if (ceph_test_mount_opt(fsc, NOQUOTADF) ||
  88             !ceph_quota_update_statfs(fsc, buf)) {
  89                 buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
  90                 buf->f_bfree = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  91                 buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  92         }
  93
  94         buf->f_files = le64_to_cpu(st.num_objects);
  95         buf->f_ffree = -1;
  96         buf->f_namelen = NAME_MAX;
  97
  98         /* Must convert the fsid, for consistent values across arches */
  99         mutex_lock(&monc->mutex);
 100         fsid = le64_to_cpu(*(__le64 *)(&monc->monmap->fsid)) ^
 101                le64_to_cpu(*((__le64 *)&monc->monmap->fsid + 1));
 102         mutex_unlock(&monc->mutex);
 103
 104         buf->f_fsid.val[0] = fsid & 0xffffffff;
 105         buf->f_fsid.val[1] = fsid >> 32;
 106
 107         return 0;
 108 }
 109
 110 static int ceph_sync_fs(struct super_block *sb, int wait)
 111 {
 112         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 113
 114         if (!wait) {
 115                 dout("sync_fs (non-blocking)\n");
 116                 ceph_flush_dirty_caps(fsc->mdsc);
 117                 dout("sync_fs (non-blocking) done\n");
 118                 return 0;
 119         }
 120
 121         dout("sync_fs (blocking)\n");
 122         ceph_osdc_sync(&fsc->client->osdc);
 123         ceph_mdsc_sync(fsc->mdsc);
 124         dout("sync_fs (blocking) done\n");
 125         return 0;
 126 }
 127
 128 /*
 129  * mount options
 130  */
 131 enum {
 132         Opt_wsize,
 133         Opt_rsize,
 134         Opt_rasize,
 135         Opt_caps_wanted_delay_min,
 136         Opt_caps_wanted_delay_max,
 137         Opt_caps_max,
 138         Opt_readdir_max_entries,
 139         Opt_readdir_max_bytes,
 140         Opt_congestion_kb,
 141         /* int args above */
 142         Opt_snapdirname,
 143         Opt_mds_namespace,
 144         Opt_recover_session,
 145         Opt_source,
 146         /* string args above */
 147         Opt_dirstat,
 148         Opt_rbytes,
 149         Opt_asyncreaddir,
 150         Opt_dcache,
 151         Opt_ino32,
 152         Opt_fscache,
 153         Opt_poolperm,
 154         Opt_require_active_mds,
 155         Opt_acl,
 156         Opt_quotadf,
 157         Opt_copyfrom,
 158         Opt_wsync,
 159 };
 160
 161 enum ceph_recover_session_mode {
 162         ceph_recover_session_no,
 163         ceph_recover_session_clean
 164 };
 165
 166 static const struct constant_table ceph_param_recover[] = {
 167         { "no",         ceph_recover_session_no },
 168         { "clean",      ceph_recover_session_clean },
 169         {}
 170 };
 171
 172 static const struct fs_parameter_spec ceph_mount_parameters[] = {
 173         fsparam_flag_no ("acl",                         Opt_acl),
 174         fsparam_flag_no ("asyncreaddir",                Opt_asyncreaddir),
 175         fsparam_s32     ("caps_max",                    Opt_caps_max),
 176         fsparam_u32     ("caps_wanted_delay_max",       Opt_caps_wanted_delay_max),
 177         fsparam_u32     ("caps_wanted_delay_min",       Opt_caps_wanted_delay_min),
 178         fsparam_u32     ("write_congestion_kb",         Opt_congestion_kb),
 179         fsparam_flag_no ("copyfrom",                    Opt_copyfrom),
 180         fsparam_flag_no ("dcache",                      Opt_dcache),
 181         fsparam_flag_no ("dirstat",                     Opt_dirstat),
 182         fsparam_flag_no ("fsc",                         Opt_fscache), // fsc|nofsc
 183         fsparam_string  ("fsc",                         Opt_fscache), // fsc=...
 184         fsparam_flag_no ("ino32",                       Opt_ino32),
 185         fsparam_string  ("mds_namespace",               Opt_mds_namespace),
 186         fsparam_flag_no ("poolperm",                    Opt_poolperm),
 187         fsparam_flag_no ("quotadf",                     Opt_quotadf),
 188         fsparam_u32     ("rasize",                      Opt_rasize),
 189         fsparam_flag_no ("rbytes",                      Opt_rbytes),
 190         fsparam_u32     ("readdir_max_bytes",           Opt_readdir_max_bytes),
 191         fsparam_u32     ("readdir_max_entries",         Opt_readdir_max_entries),
 192         fsparam_enum    ("recover_session",             Opt_recover_session, ceph_param_recover),
 193         fsparam_flag_no ("require_active_mds",          Opt_require_active_mds),
 194         fsparam_u32     ("rsize",                       Opt_rsize),
 195         fsparam_string  ("snapdirname",                 Opt_snapdirname),
 196         fsparam_string  ("source",                      Opt_source),
 197         fsparam_u32     ("wsize",                       Opt_wsize),
 198         fsparam_flag_no ("wsync",                       Opt_wsync),
 199         {}
 200 };
 201
 202 struct ceph_parse_opts_ctx {
 203         struct ceph_options             *copts;
 204         struct ceph_mount_options       *opts;
 205 };
 206
 207 /*
 208  * Remove adjacent slashes and then the trailing slash, unless it is
 209  * the only remaining character.
 210  *
 211  * E.g. "//dir1////dir2///" --> "/dir1/dir2", "///" --> "/".
 212  */
 213 static void canonicalize_path(char *path)
 214 {
 215         int i, j = 0;
 216
 217         for (i = 0; path[i] != '\0'; i++) {
 218                 if (path[i] != '/' || j < 1 || path[j - 1] != '/')
 219                         path[j++] = path[i];
 220         }
 221
 222         if (j > 1 && path[j - 1] == '/')
 223                 j--;
 224         path[j] = '\0';
 225 }
 226
 227 /*
 228  * Parse the source parameter.  Distinguish the server list from the path.
 229  *
 230  * The source will look like:
 231  *     <server_spec>[,<server_spec>...]:[<path>]
 232  * where
 233  *     <server_spec> is <ip>[:<port>]
 234  *     <path> is optional, but if present must begin with '/'
 235  */
 236 static int ceph_parse_source(struct fs_parameter *param, struct fs_context *fc)
 237 {
 238         struct ceph_parse_opts_ctx *pctx = fc->fs_private;
 239         struct ceph_mount_options *fsopt = pctx->opts;
 240         char *dev_name = param->string, *dev_name_end;
 241         int ret;
 242
 243         dout("%s '%s'\n", __func__, dev_name);
 244         if (!dev_name || !*dev_name)
 245                 return invalfc(fc, "Empty source");
 246
 247         dev_name_end = strchr(dev_name, '/');
 248         if (dev_name_end) {
 249                 /*
 250                  * The server_path will include the whole chars from userland
 251                  * including the leading '/'.
 252                  */
 253                 kfree(fsopt->server_path);
 254                 fsopt->server_path = kstrdup(dev_name_end, GFP_KERNEL);
 255                 if (!fsopt->server_path)
 256                         return -ENOMEM;
 257
 258                 canonicalize_path(fsopt->server_path);
 259         } else {
 260                 dev_name_end = dev_name + strlen(dev_name);
 261         }
 262
 263         dev_name_end--;         /* back up to ':' separator */
 264         if (dev_name_end < dev_name || *dev_name_end != ':')
 265                 return invalfc(fc, "No path or : separator in source");
 266
 267         dout("device name '%.*s'\n", (int)(dev_name_end - dev_name), dev_name);
 268         if (fsopt->server_path)
 269                 dout("server path '%s'\n", fsopt->server_path);
 270
 271         ret = ceph_parse_mon_ips(param->string, dev_name_end - dev_name,
 272                                  pctx->copts, fc->log.log);
 273         if (ret)
 274                 return ret;
 275
 276         fc->source = param->string;
 277         param->string = NULL;
 278         return 0;
 279 }
 280
 281 static int ceph_parse_mount_param(struct fs_context *fc,
 282                                   struct fs_parameter *param)
 283 {
 284         struct ceph_parse_opts_ctx *pctx = fc->fs_private;
 285         struct ceph_mount_options *fsopt = pctx->opts;
 286         struct fs_parse_result result;
 287         unsigned int mode;
 288         int token, ret;
 289
 290         ret = ceph_parse_param(param, pctx->copts, fc->log.log);
 291         if (ret != -ENOPARAM)
 292                 return ret;
 293
 294         token = fs_parse(fc, ceph_mount_parameters, param, &result);
 295         dout("%s fs_parse '%s' token %d\n", __func__, param->key, token);
 296         if (token < 0)
 297                 return token;
 298
 299         switch (token) {
 300         case Opt_snapdirname:
 301                 kfree(fsopt->snapdir_name);
 302                 fsopt->snapdir_name = param->string;
 303                 param->string = NULL;
 304                 break;
 305         case Opt_mds_namespace:
 306                 kfree(fsopt->mds_namespace);
 307                 fsopt->mds_namespace = param->string;
 308                 param->string = NULL;
 309                 break;
 310         case Opt_recover_session:
 311                 mode = result.uint_32;
 312                 if (mode == ceph_recover_session_no)
 313                         fsopt->flags &= ~CEPH_MOUNT_OPT_CLEANRECOVER;
 314                 else if (mode == ceph_recover_session_clean)
 315                         fsopt->flags |= CEPH_MOUNT_OPT_CLEANRECOVER;
 316                 else
 317                         BUG();
 318                 break;
 319         case Opt_source:
 320                 if (fc->source)
 321                         return invalfc(fc, "Multiple sources specified");
 322                 return ceph_parse_source(param, fc);
 323         case Opt_wsize:
 324                 if (result.uint_32 < PAGE_SIZE ||
 325                     result.uint_32 > CEPH_MAX_WRITE_SIZE)
 326                         goto out_of_range;
 327                 fsopt->wsize = ALIGN(result.uint_32, PAGE_SIZE);
 328                 break;
 329         case Opt_rsize:
 330                 if (result.uint_32 < PAGE_SIZE ||
 331                     result.uint_32 > CEPH_MAX_READ_SIZE)
 332                         goto out_of_range;
 333                 fsopt->rsize = ALIGN(result.uint_32, PAGE_SIZE);
 334                 break;
 335         case Opt_rasize:
 336                 fsopt->rasize = ALIGN(result.uint_32, PAGE_SIZE);
 337                 break;
 338         case Opt_caps_wanted_delay_min:
 339                 if (result.uint_32 < 1)
 340                         goto out_of_range;
 341                 fsopt->caps_wanted_delay_min = result.uint_32;
 342                 break;
 343         case Opt_caps_wanted_delay_max:
 344                 if (result.uint_32 < 1)
 345                         goto out_of_range;
 346                 fsopt->caps_wanted_delay_max = result.uint_32;
 347                 break;
 348         case Opt_caps_max:
 349                 if (result.int_32 < 0)
 350                         goto out_of_range;
 351                 fsopt->caps_max = result.int_32;
 352                 break;
 353         case Opt_readdir_max_entries:
 354                 if (result.uint_32 < 1)
 355                         goto out_of_range;
 356                 fsopt->max_readdir = result.uint_32;
 357                 break;
 358         case Opt_readdir_max_bytes:
 359                 if (result.uint_32 < PAGE_SIZE && result.uint_32 != 0)
 360                         goto out_of_range;
 361                 fsopt->max_readdir_bytes = result.uint_32;
 362                 break;
 363         case Opt_congestion_kb:
 364                 if (result.uint_32 < 1024) /* at least 1M */
 365                         goto out_of_range;
 366                 fsopt->congestion_kb = result.uint_32;
 367                 break;
 368         case Opt_dirstat:
 369                 if (!result.negated)
 370                         fsopt->flags |= CEPH_MOUNT_OPT_DIRSTAT;
 371                 else
 372                         fsopt->flags &= ~CEPH_MOUNT_OPT_DIRSTAT;
 373                 break;
 374         case Opt_rbytes:
 375                 if (!result.negated)
 376                         fsopt->flags |= CEPH_MOUNT_OPT_RBYTES;
 377                 else
 378                         fsopt->flags &= ~CEPH_MOUNT_OPT_RBYTES;
 379                 break;
 380         case Opt_asyncreaddir:
 381                 if (!result.negated)
 382                         fsopt->flags &= ~CEPH_MOUNT_OPT_NOASYNCREADDIR;
 383                 else
 384                         fsopt->flags |= CEPH_MOUNT_OPT_NOASYNCREADDIR;
 385                 break;
 386         case Opt_dcache:
 387                 if (!result.negated)
 388                         fsopt->flags |= CEPH_MOUNT_OPT_DCACHE;
 389                 else
 390                         fsopt->flags &= ~CEPH_MOUNT_OPT_DCACHE;
 391                 break;
 392         case Opt_ino32:
 393                 if (!result.negated)
 394                         fsopt->flags |= CEPH_MOUNT_OPT_INO32;
 395                 else
 396                         fsopt->flags &= ~CEPH_MOUNT_OPT_INO32;
 397                 break;
 398
 399         case Opt_fscache:
 400 #ifdef CONFIG_CEPH_FSCACHE
 401                 kfree(fsopt->fscache_uniq);
 402                 fsopt->fscache_uniq = NULL;
 403                 if (result.negated) {
 404                         fsopt->flags &= ~CEPH_MOUNT_OPT_FSCACHE;
 405                 } else {
 406                         fsopt->flags |= CEPH_MOUNT_OPT_FSCACHE;
 407                         fsopt->fscache_uniq = param->string;
 408                         param->string = NULL;
 409                 }
 410                 break;
 411 #else
 412                 return invalfc(fc, "fscache support is disabled");
 413 #endif
 414         case Opt_poolperm:
 415                 if (!result.negated)
 416                         fsopt->flags &= ~CEPH_MOUNT_OPT_NOPOOLPERM;
 417                 else
 418                         fsopt->flags |= CEPH_MOUNT_OPT_NOPOOLPERM;
 419                 break;
 420         case Opt_require_active_mds:
 421                 if (!result.negated)
 422                         fsopt->flags &= ~CEPH_MOUNT_OPT_MOUNTWAIT;
 423                 else
 424                         fsopt->flags |= CEPH_MOUNT_OPT_MOUNTWAIT;
 425                 break;
 426         case Opt_quotadf:
 427                 if (!result.negated)
 428                         fsopt->flags &= ~CEPH_MOUNT_OPT_NOQUOTADF;
 429                 else
 430                         fsopt->flags |= CEPH_MOUNT_OPT_NOQUOTADF;
 431                 break;
 432         case Opt_copyfrom:
 433                 if (!result.negated)
 434                         fsopt->flags &= ~CEPH_MOUNT_OPT_NOCOPYFROM;
 435                 else
 436                         fsopt->flags |= CEPH_MOUNT_OPT_NOCOPYFROM;
 437                 break;
 438         case Opt_acl:
 439                 if (!result.negated) {
 440 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 441                         fc->sb_flags |= SB_POSIXACL;
 442 #else
 443                         return invalfc(fc, "POSIX ACL support is disabled");
 444 #endif
 445                 } else {
 446                         fc->sb_flags &= ~SB_POSIXACL;
 447                 }
 448                 break;
 449         case Opt_wsync:
 450                 if (!result.negated)
 451                         fsopt->flags &= ~CEPH_MOUNT_OPT_ASYNC_DIROPS;
 452                 else
 453                         fsopt->flags |= CEPH_MOUNT_OPT_ASYNC_DIROPS;
 454                 break;
 455         default:
 456                 BUG();
 457         }
 458         return 0;
 459
 460 out_of_range:
 461         return invalfc(fc, "%s out of range", param->key);
 462 }
 463
 464 static void destroy_mount_options(struct ceph_mount_options *args)
 465 {
 466         dout("destroy_mount_options %p\n", args);
 467         if (!args)
 468                 return;
 469
 470         kfree(args->snapdir_name);
 471         kfree(args->mds_namespace);
 472         kfree(args->server_path);
 473         kfree(args->fscache_uniq);
 474         kfree(args);
 475 }
 476
 477 static int strcmp_null(const char *s1, const char *s2)
 478 {
 479         if (!s1 && !s2)
 480                 return 0;
 481         if (s1 && !s2)
 482                 return -1;
 483         if (!s1 && s2)
 484                 return 1;
 485         return strcmp(s1, s2);
 486 }
 487
 488 static int compare_mount_options(struct ceph_mount_options *new_fsopt,
 489                                  struct ceph_options *new_opt,
 490                                  struct ceph_fs_client *fsc)
 491 {
 492         struct ceph_mount_options *fsopt1 = new_fsopt;
 493         struct ceph_mount_options *fsopt2 = fsc->mount_options;
 494         int ofs = offsetof(struct ceph_mount_options, snapdir_name);
 495         int ret;
 496
 497         ret = memcmp(fsopt1, fsopt2, ofs);
 498         if (ret)
 499                 return ret;
 500
 501         ret = strcmp_null(fsopt1->snapdir_name, fsopt2->snapdir_name);
 502         if (ret)
 503                 return ret;
 504
 505         ret = strcmp_null(fsopt1->mds_namespace, fsopt2->mds_namespace);
 506         if (ret)
 507                 return ret;
 508
 509         ret = strcmp_null(fsopt1->server_path, fsopt2->server_path);
 510         if (ret)
 511                 return ret;
 512
 513         ret = strcmp_null(fsopt1->fscache_uniq, fsopt2->fscache_uniq);
 514         if (ret)
 515                 return ret;
 516
 517         return ceph_compare_options(new_opt, fsc->client);
 518 }
 519
 520 /**
 521  * ceph_show_options - Show mount options in /proc/mounts
 522  * @m: seq_file to write to
 523  * @root: root of that (sub)tree
 524  */
 525 static int ceph_show_options(struct seq_file *m, struct dentry *root)
 526 {
 527         struct ceph_fs_client *fsc = ceph_sb_to_client(root->d_sb);
 528         struct ceph_mount_options *fsopt = fsc->mount_options;
 529         size_t pos;
 530         int ret;
 531
 532         /* a comma between MNT/MS and client options */
 533         seq_putc(m, ',');
 534         pos = m->count;
 535
 536         ret = ceph_print_client_options(m, fsc->client, false);
 537         if (ret)
 538                 return ret;
 539
 540         /* retract our comma if no client options */
 541         if (m->count == pos)
 542                 m->count--;
 543
 544         if (fsopt->flags & CEPH_MOUNT_OPT_DIRSTAT)
 545                 seq_puts(m, ",dirstat");
 546         if ((fsopt->flags & CEPH_MOUNT_OPT_RBYTES))
 547                 seq_puts(m, ",rbytes");
 548         if (fsopt->flags & CEPH_MOUNT_OPT_NOASYNCREADDIR)
 549                 seq_puts(m, ",noasyncreaddir");
 550         if ((fsopt->flags & CEPH_MOUNT_OPT_DCACHE) == 0)
 551                 seq_puts(m, ",nodcache");
 552         if (fsopt->flags & CEPH_MOUNT_OPT_INO32)
 553                 seq_puts(m, ",ino32");
 554         if (fsopt->flags & CEPH_MOUNT_OPT_FSCACHE) {
 555                 seq_show_option(m, "fsc", fsopt->fscache_uniq);
 556         }
 557         if (fsopt->flags & CEPH_MOUNT_OPT_NOPOOLPERM)
 558                 seq_puts(m, ",nopoolperm");
 559         if (fsopt->flags & CEPH_MOUNT_OPT_NOQUOTADF)
 560                 seq_puts(m, ",noquotadf");
 561
 562 #ifdef CONFIG_CEPH_FS_POSIX_ACL
 563         if (root->d_sb->s_flags & SB_POSIXACL)
 564                 seq_puts(m, ",acl");
 565         else
 566                 seq_puts(m, ",noacl");
 567 #endif
 568
 569         if ((fsopt->flags & CEPH_MOUNT_OPT_NOCOPYFROM) == 0)
 570                 seq_puts(m, ",copyfrom");
 571
 572         if (fsopt->mds_namespace)
 573                 seq_show_option(m, "mds_namespace", fsopt->mds_namespace);
 574
 575         if (fsopt->flags & CEPH_MOUNT_OPT_CLEANRECOVER)
 576                 seq_show_option(m, "recover_session", "clean");
 577
 578         if (fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
 579                 seq_puts(m, ",nowsync");
 580
 581         if (fsopt->wsize != CEPH_MAX_WRITE_SIZE)
 582                 seq_printf(m, ",wsize=%u", fsopt->wsize);
 583         if (fsopt->rsize != CEPH_MAX_READ_SIZE)
 584                 seq_printf(m, ",rsize=%u", fsopt->rsize);
 585         if (fsopt->rasize != CEPH_RASIZE_DEFAULT)
 586                 seq_printf(m, ",rasize=%u", fsopt->rasize);
 587         if (fsopt->congestion_kb != default_congestion_kb())
 588                 seq_printf(m, ",write_congestion_kb=%u", fsopt->congestion_kb);
 589         if (fsopt->caps_max)
 590                 seq_printf(m, ",caps_max=%d", fsopt->caps_max);
 591         if (fsopt->caps_wanted_delay_min != CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT)
 592                 seq_printf(m, ",caps_wanted_delay_min=%u",
 593                          fsopt->caps_wanted_delay_min);
 594         if (fsopt->caps_wanted_delay_max != CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT)
 595                 seq_printf(m, ",caps_wanted_delay_max=%u",
 596                            fsopt->caps_wanted_delay_max);
 597         if (fsopt->max_readdir != CEPH_MAX_READDIR_DEFAULT)
 598                 seq_printf(m, ",readdir_max_entries=%u", fsopt->max_readdir);
 599         if (fsopt->max_readdir_bytes != CEPH_MAX_READDIR_BYTES_DEFAULT)
 600                 seq_printf(m, ",readdir_max_bytes=%u", fsopt->max_readdir_bytes);
 601         if (strcmp(fsopt->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 602                 seq_show_option(m, "snapdirname", fsopt->snapdir_name);
 603
 604         return 0;
 605 }
 606
 607 /*
 608  * handle any mon messages the standard library doesn't understand.
 609  * return error if we don't either.
 610  */
 611 static int extra_mon_dispatch(struct ceph_client *client, struct ceph_msg *msg)
 612 {
 613         struct ceph_fs_client *fsc = client->private;
 614         int type = le16_to_cpu(msg->hdr.type);
 615
 616         switch (type) {
 617         case CEPH_MSG_MDS_MAP:
 618                 ceph_mdsc_handle_mdsmap(fsc->mdsc, msg);
 619                 return 0;
 620         case CEPH_MSG_FS_MAP_USER:
 621                 ceph_mdsc_handle_fsmap(fsc->mdsc, msg);
 622                 return 0;
 623         default:
 624                 return -1;
 625         }
 626 }
 627
 628 /*
 629  * create a new fs client
 630  *
 631  * Success or not, this function consumes @fsopt and @opt.
 632  */
 633 static struct ceph_fs_client *create_fs_client(struct ceph_mount_options *fsopt,
 634                                         struct ceph_options *opt)
 635 {
 636         struct ceph_fs_client *fsc;
 637         int page_count;
 638         size_t size;
 639         int err;
 640
 641         fsc = kzalloc(sizeof(*fsc), GFP_KERNEL);
 642         if (!fsc) {
 643                 err = -ENOMEM;
 644                 goto fail;
 645         }
 646
 647         fsc->client = ceph_create_client(opt, fsc);
 648         if (IS_ERR(fsc->client)) {
 649                 err = PTR_ERR(fsc->client);
 650                 goto fail;
 651         }
 652         opt = NULL; /* fsc->client now owns this */
 653
 654         fsc->client->extra_mon_dispatch = extra_mon_dispatch;
 655         ceph_set_opt(fsc->client, ABORT_ON_FULL);
 656
 657         if (!fsopt->mds_namespace) {
 658                 ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_MDSMAP,
 659                                    0, true);
 660         } else {
 661                 ceph_monc_want_map(&fsc->client->monc, CEPH_SUB_FSMAP,
 662                                    0, false);
 663         }
 664
 665         fsc->mount_options = fsopt;
 666
 667         fsc->sb = NULL;
 668         fsc->mount_state = CEPH_MOUNT_MOUNTING;
 669         fsc->filp_gen = 1;
 670         fsc->have_copy_from2 = true;
 671
 672         atomic_long_set(&fsc->writeback_count, 0);
 673
 674         err = -ENOMEM;
 675         /*
 676          * The number of concurrent works can be high but they don't need
 677          * to be processed in parallel, limit concurrency.
 678          */
 679         fsc->inode_wq = alloc_workqueue("ceph-inode", WQ_UNBOUND, 0);
 680         if (!fsc->inode_wq)
 681                 goto fail_client;
 682         fsc->cap_wq = alloc_workqueue("ceph-cap", 0, 1);
 683         if (!fsc->cap_wq)
 684                 goto fail_inode_wq;
 685
 686         /* set up mempools */
 687         err = -ENOMEM;
 688         page_count = fsc->mount_options->wsize >> PAGE_SHIFT;
 689         size = sizeof (struct page *) * (page_count ? page_count : 1);
 690         fsc->wb_pagevec_pool = mempool_create_kmalloc_pool(10, size);
 691         if (!fsc->wb_pagevec_pool)
 692                 goto fail_cap_wq;
 693
 694         return fsc;
 695
 696 fail_cap_wq:
 697         destroy_workqueue(fsc->cap_wq);
 698 fail_inode_wq:
 699         destroy_workqueue(fsc->inode_wq);
 700 fail_client:
 701         ceph_destroy_client(fsc->client);
 702 fail:
 703         kfree(fsc);
 704         if (opt)
 705                 ceph_destroy_options(opt);
 706         destroy_mount_options(fsopt);
 707         return ERR_PTR(err);
 708 }
 709
 710 static void flush_fs_workqueues(struct ceph_fs_client *fsc)
 711 {
 712         flush_workqueue(fsc->inode_wq);
 713         flush_workqueue(fsc->cap_wq);
 714 }
 715
 716 static void destroy_fs_client(struct ceph_fs_client *fsc)
 717 {
 718         dout("destroy_fs_client %p\n", fsc);
 719
 720         ceph_mdsc_destroy(fsc);
 721         destroy_workqueue(fsc->inode_wq);
 722         destroy_workqueue(fsc->cap_wq);
 723
 724         mempool_destroy(fsc->wb_pagevec_pool);
 725
 726         destroy_mount_options(fsc->mount_options);
 727
 728         ceph_destroy_client(fsc->client);
 729
 730         kfree(fsc);
 731         dout("destroy_fs_client %p done\n", fsc);
 732 }
 733
 734 /*
 735  * caches
 736  */
 737 struct kmem_cache *ceph_inode_cachep;
 738 struct kmem_cache *ceph_cap_cachep;
 739 struct kmem_cache *ceph_cap_flush_cachep;
 740 struct kmem_cache *ceph_dentry_cachep;
 741 struct kmem_cache *ceph_file_cachep;
 742 struct kmem_cache *ceph_dir_file_cachep;
 743 struct kmem_cache *ceph_mds_request_cachep;
 744
 745 static void ceph_inode_init_once(void *foo)
 746 {
 747         struct ceph_inode_info *ci = foo;
 748         inode_init_once(&ci->vfs_inode);
 749 }
 750
 751 static int __init init_caches(void)
 752 {
 753         int error = -ENOMEM;
 754
 755         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 756                                       sizeof(struct ceph_inode_info),
 757                                       __alignof__(struct ceph_inode_info),
 758                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD|
 759                                       SLAB_ACCOUNT, ceph_inode_init_once);
 760         if (!ceph_inode_cachep)
 761                 return -ENOMEM;
 762
 763         ceph_cap_cachep = KMEM_CACHE(ceph_cap, SLAB_MEM_SPREAD);
 764         if (!ceph_cap_cachep)
 765                 goto bad_cap;
 766         ceph_cap_flush_cachep = KMEM_CACHE(ceph_cap_flush,
 767                                            SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 768         if (!ceph_cap_flush_cachep)
 769                 goto bad_cap_flush;
 770
 771         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 772                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 773         if (!ceph_dentry_cachep)
 774                 goto bad_dentry;
 775
 776         ceph_file_cachep = KMEM_CACHE(ceph_file_info, SLAB_MEM_SPREAD);
 777         if (!ceph_file_cachep)
 778                 goto bad_file;
 779
 780         ceph_dir_file_cachep = KMEM_CACHE(ceph_dir_file_info, SLAB_MEM_SPREAD);
 781         if (!ceph_dir_file_cachep)
 782                 goto bad_dir_file;
 783
 784         ceph_mds_request_cachep = KMEM_CACHE(ceph_mds_request, SLAB_MEM_SPREAD);
 785         if (!ceph_mds_request_cachep)
 786                 goto bad_mds_req;
 787
 788         error = ceph_fscache_register();
 789         if (error)
 790                 goto bad_fscache;
 791
 792         return 0;
 793
 794 bad_fscache:
 795         kmem_cache_destroy(ceph_mds_request_cachep);
 796 bad_mds_req:
 797         kmem_cache_destroy(ceph_dir_file_cachep);
 798 bad_dir_file:
 799         kmem_cache_destroy(ceph_file_cachep);
 800 bad_file:
 801         kmem_cache_destroy(ceph_dentry_cachep);
 802 bad_dentry:
 803         kmem_cache_destroy(ceph_cap_flush_cachep);
 804 bad_cap_flush:
 805         kmem_cache_destroy(ceph_cap_cachep);
 806 bad_cap:
 807         kmem_cache_destroy(ceph_inode_cachep);
 808         return error;
 809 }
 810
 811 static void destroy_caches(void)
 812 {
 813         /*
 814          * Make sure all delayed rcu free inodes are flushed before we
 815          * destroy cache.
 816          */
 817         rcu_barrier();
 818
 819         kmem_cache_destroy(ceph_inode_cachep);
 820         kmem_cache_destroy(ceph_cap_cachep);
 821         kmem_cache_destroy(ceph_cap_flush_cachep);
 822         kmem_cache_destroy(ceph_dentry_cachep);
 823         kmem_cache_destroy(ceph_file_cachep);
 824         kmem_cache_destroy(ceph_dir_file_cachep);
 825         kmem_cache_destroy(ceph_mds_request_cachep);
 826
 827         ceph_fscache_unregister();
 828 }
 829
 830 /*
 831  * ceph_umount_begin - initiate forced umount.  Tear down down the
 832  * mount, skipping steps that may hang while waiting for server(s).
 833  */
 834 static void ceph_umount_begin(struct super_block *sb)
 835 {
 836         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
 837
 838         dout("ceph_umount_begin - starting forced umount\n");
 839         if (!fsc)
 840                 return;
 841         fsc->mount_state = CEPH_MOUNT_SHUTDOWN;
 842         ceph_osdc_abort_requests(&fsc->client->osdc, -EIO);
 843         ceph_mdsc_force_umount(fsc->mdsc);
 844         fsc->filp_gen++; // invalidate open files
 845 }
 846
 847 static const struct super_operations ceph_super_ops = {
 848         .alloc_inode    = ceph_alloc_inode,
 849         .free_inode     = ceph_free_inode,
 850         .write_inode    = ceph_write_inode,
 851         .drop_inode     = generic_delete_inode,
 852         .evict_inode    = ceph_evict_inode,
 853         .sync_fs        = ceph_sync_fs,
 854         .put_super      = ceph_put_super,
 855         .show_options   = ceph_show_options,
 856         .statfs         = ceph_statfs,
 857         .umount_begin   = ceph_umount_begin,
 858 };
 859
 860 /*
 861  * Bootstrap mount by opening the root directory.  Note the mount
 862  * @started time from caller, and time out if this takes too long.
 863  */
 864 static struct dentry *open_root_dentry(struct ceph_fs_client *fsc,
 865                                        const char *path,
 866                                        unsigned long started)
 867 {
 868         struct ceph_mds_client *mdsc = fsc->mdsc;
 869         struct ceph_mds_request *req = NULL;
 870         int err;
 871         struct dentry *root;
 872
 873         /* open dir */
 874         dout("open_root_inode opening '%s'\n", path);
 875         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 876         if (IS_ERR(req))
 877                 return ERR_CAST(req);
 878         req->r_path1 = kstrdup(path, GFP_NOFS);
 879         if (!req->r_path1) {
 880                 root = ERR_PTR(-ENOMEM);
 881                 goto out;
 882         }
 883
 884         req->r_ino1.ino = CEPH_INO_ROOT;
 885         req->r_ino1.snap = CEPH_NOSNAP;
 886         req->r_started = started;
 887         req->r_timeout = fsc->client->options->mount_timeout;
 888         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 889         req->r_num_caps = 2;
 890         err = ceph_mdsc_do_request(mdsc, NULL, req);
 891         if (err == 0) {
 892                 struct inode *inode = req->r_target_inode;
 893                 req->r_target_inode = NULL;
 894                 dout("open_root_inode success\n");
 895                 root = d_make_root(inode);
 896                 if (!root) {
 897                         root = ERR_PTR(-ENOMEM);
 898                         goto out;
 899                 }
 900                 dout("open_root_inode success, root dentry is %p\n", root);
 901         } else {
 902                 root = ERR_PTR(err);
 903         }
 904 out:
 905         ceph_mdsc_put_request(req);
 906         return root;
 907 }
 908
 909 /*
 910  * mount: join the ceph cluster, and open root directory.
 911  */
 912 static struct dentry *ceph_real_mount(struct ceph_fs_client *fsc,
 913                                       struct fs_context *fc)
 914 {
 915         int err;
 916         unsigned long started = jiffies;  /* note the start time */
 917         struct dentry *root;
 918
 919         dout("mount start %p\n", fsc);
 920         mutex_lock(&fsc->client->mount_mutex);
 921
 922         if (!fsc->sb->s_root) {
 923                 const char *path = fsc->mount_options->server_path ?
 924                                      fsc->mount_options->server_path + 1 : "";
 925
 926                 err = __ceph_open_session(fsc->client, started);
 927                 if (err < 0)
 928                         goto out;
 929
 930                 /* setup fscache */
 931                 if (fsc->mount_options->flags & CEPH_MOUNT_OPT_FSCACHE) {
 932                         err = ceph_fscache_register_fs(fsc, fc);
 933                         if (err < 0)
 934                                 goto out;
 935                 }
 936
 937                 dout("mount opening path '%s'\n", path);
 938
 939                 ceph_fs_debugfs_init(fsc);
 940
 941                 root = open_root_dentry(fsc, path, started);
 942                 if (IS_ERR(root)) {
 943                         err = PTR_ERR(root);
 944                         goto out;
 945                 }
 946                 fsc->sb->s_root = dget(root);
 947         } else {
 948                 root = dget(fsc->sb->s_root);
 949         }
 950
 951         fsc->mount_state = CEPH_MOUNT_MOUNTED;
 952         dout("mount success\n");
 953         mutex_unlock(&fsc->client->mount_mutex);
 954         return root;
 955
 956 out:
 957         mutex_unlock(&fsc->client->mount_mutex);
 958         return ERR_PTR(err);
 959 }
 960
 961 static int ceph_set_super(struct super_block *s, struct fs_context *fc)
 962 {
 963         struct ceph_fs_client *fsc = s->s_fs_info;
 964         int ret;
 965
 966         dout("set_super %p\n", s);
 967
 968         s->s_maxbytes = MAX_LFS_FILESIZE;
 969
 970         s->s_xattr = ceph_xattr_handlers;
 971         fsc->sb = s;
 972         fsc->max_file_size = 1ULL << 40; /* temp value until we get mdsmap */
 973
 974         s->s_op = &ceph_super_ops;
 975         s->s_d_op = &ceph_dentry_ops;
 976         s->s_export_op = &ceph_export_ops;
 977
 978         s->s_time_gran = 1;
 979         s->s_time_min = 0;
 980         s->s_time_max = U32_MAX;
 981
 982         ret = set_anon_super_fc(s, fc);
 983         if (ret != 0)
 984                 fsc->sb = NULL;
 985         return ret;
 986 }
 987
 988 /*
 989  * share superblock if same fs AND options
 990  */
 991 static int ceph_compare_super(struct super_block *sb, struct fs_context *fc)
 992 {
 993         struct ceph_fs_client *new = fc->s_fs_info;
 994         struct ceph_mount_options *fsopt = new->mount_options;
 995         struct ceph_options *opt = new->client->options;
 996         struct ceph_fs_client *other = ceph_sb_to_client(sb);
 997
 998         dout("ceph_compare_super %p\n", sb);
 999
1000         if (compare_mount_options(fsopt, opt, other)) {
1001                 dout("monitor(s)/mount options don't match\n");
1002                 return 0;
1003         }
1004         if ((opt->flags & CEPH_OPT_FSID) &&
1005             ceph_fsid_compare(&opt->fsid, &other->client->fsid)) {
1006                 dout("fsid doesn't match\n");
1007                 return 0;
1008         }
1009         if (fc->sb_flags != (sb->s_flags & ~SB_BORN)) {
1010                 dout("flags differ\n");
1011                 return 0;
1012         }
1013         return 1;
1014 }
1015
1016 /*
1017  * construct our own bdi so we can control readahead, etc.
1018  */
1019 static atomic_long_t bdi_seq = ATOMIC_LONG_INIT(0);
1020
1021 static int ceph_setup_bdi(struct super_block *sb, struct ceph_fs_client *fsc)
1022 {
1023         int err;
1024
1025         err = super_setup_bdi_name(sb, "ceph-%ld",
1026                                    atomic_long_inc_return(&bdi_seq));
1027         if (err)
1028                 return err;
1029
1030         /* set ra_pages based on rasize mount option? */
1031         sb->s_bdi->ra_pages = fsc->mount_options->rasize >> PAGE_SHIFT;
1032
1033         /* set io_pages based on max osd read size */
1034         sb->s_bdi->io_pages = fsc->mount_options->rsize >> PAGE_SHIFT;
1035
1036         return 0;
1037 }
1038
1039 static int ceph_get_tree(struct fs_context *fc)
1040 {
1041         struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1042         struct super_block *sb;
1043         struct ceph_fs_client *fsc;
1044         struct dentry *res;
1045         int (*compare_super)(struct super_block *, struct fs_context *) =
1046                 ceph_compare_super;
1047         int err;
1048
1049         dout("ceph_get_tree\n");
1050
1051         if (!fc->source)
1052                 return invalfc(fc, "No source");
1053
1054         /* create client (which we may/may not use) */
1055         fsc = create_fs_client(pctx->opts, pctx->copts);
1056         pctx->opts = NULL;
1057         pctx->copts = NULL;
1058         if (IS_ERR(fsc)) {
1059                 err = PTR_ERR(fsc);
1060                 goto out_final;
1061         }
1062
1063         err = ceph_mdsc_init(fsc);
1064         if (err < 0)
1065                 goto out;
1066
1067         if (ceph_test_opt(fsc->client, NOSHARE))
1068                 compare_super = NULL;
1069
1070         fc->s_fs_info = fsc;
1071         sb = sget_fc(fc, compare_super, ceph_set_super);
1072         fc->s_fs_info = NULL;
1073         if (IS_ERR(sb)) {
1074                 err = PTR_ERR(sb);
1075                 goto out;
1076         }
1077
1078         if (ceph_sb_to_client(sb) != fsc) {
1079                 destroy_fs_client(fsc);
1080                 fsc = ceph_sb_to_client(sb);
1081                 dout("get_sb got existing client %p\n", fsc);
1082         } else {
1083                 dout("get_sb using new client %p\n", fsc);
1084                 err = ceph_setup_bdi(sb, fsc);
1085                 if (err < 0)
1086                         goto out_splat;
1087         }
1088
1089         res = ceph_real_mount(fsc, fc);
1090         if (IS_ERR(res)) {
1091                 err = PTR_ERR(res);
1092                 goto out_splat;
1093         }
1094         dout("root %p inode %p ino %llx.%llx\n", res,
1095              d_inode(res), ceph_vinop(d_inode(res)));
1096         fc->root = fsc->sb->s_root;
1097         return 0;
1098
1099 out_splat:
1100         if (!ceph_mdsmap_is_cluster_available(fsc->mdsc->mdsmap)) {
1101                 pr_info("No mds server is up or the cluster is laggy\n");
1102                 err = -EHOSTUNREACH;
1103         }
1104
1105         ceph_mdsc_close_sessions(fsc->mdsc);
1106         deactivate_locked_super(sb);
1107         goto out_final;
1108
1109 out:
1110         destroy_fs_client(fsc);
1111 out_final:
1112         dout("ceph_get_tree fail %d\n", err);
1113         return err;
1114 }
1115
1116 static void ceph_free_fc(struct fs_context *fc)
1117 {
1118         struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1119
1120         if (pctx) {
1121                 destroy_mount_options(pctx->opts);
1122                 ceph_destroy_options(pctx->copts);
1123                 kfree(pctx);
1124         }
1125 }
1126
1127 static int ceph_reconfigure_fc(struct fs_context *fc)
1128 {
1129         struct ceph_parse_opts_ctx *pctx = fc->fs_private;
1130         struct ceph_mount_options *fsopt = pctx->opts;
1131         struct ceph_fs_client *fsc = ceph_sb_to_client(fc->root->d_sb);
1132
1133         if (fsopt->flags & CEPH_MOUNT_OPT_ASYNC_DIROPS)
1134                 ceph_set_mount_opt(fsc, ASYNC_DIROPS);
1135         else
1136                 ceph_clear_mount_opt(fsc, ASYNC_DIROPS);
1137
1138         sync_filesystem(fc->root->d_sb);
1139         return 0;
1140 }
1141
1142 static const struct fs_context_operations ceph_context_ops = {
1143         .free           = ceph_free_fc,
1144         .parse_param    = ceph_parse_mount_param,
1145         .get_tree       = ceph_get_tree,
1146         .reconfigure    = ceph_reconfigure_fc,
1147 };
1148
1149 /*
1150  * Set up the filesystem mount context.
1151  */
1152 static int ceph_init_fs_context(struct fs_context *fc)
1153 {
1154         struct ceph_parse_opts_ctx *pctx;
1155         struct ceph_mount_options *fsopt;
1156
1157         pctx = kzalloc(sizeof(*pctx), GFP_KERNEL);
1158         if (!pctx)
1159                 return -ENOMEM;
1160
1161         pctx->copts = ceph_alloc_options();
1162         if (!pctx->copts)
1163                 goto nomem;
1164
1165         pctx->opts = kzalloc(sizeof(*pctx->opts), GFP_KERNEL);
1166         if (!pctx->opts)
1167                 goto nomem;
1168
1169         fsopt = pctx->opts;
1170         fsopt->flags = CEPH_MOUNT_OPT_DEFAULT;
1171
1172         fsopt->wsize = CEPH_MAX_WRITE_SIZE;
1173         fsopt->rsize = CEPH_MAX_READ_SIZE;
1174         fsopt->rasize = CEPH_RASIZE_DEFAULT;
1175         fsopt->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
1176         if (!fsopt->snapdir_name)
1177                 goto nomem;
1178
1179         fsopt->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
1180         fsopt->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
1181         fsopt->max_readdir = CEPH_MAX_READDIR_DEFAULT;
1182         fsopt->max_readdir_bytes = CEPH_MAX_READDIR_BYTES_DEFAULT;
1183         fsopt->congestion_kb = default_congestion_kb();
1184
1185 #ifdef CONFIG_CEPH_FS_POSIX_ACL
1186         fc->sb_flags |= SB_POSIXACL;
1187 #endif
1188
1189         fc->fs_private = pctx;
1190         fc->ops = &ceph_context_ops;
1191         return 0;
1192
1193 nomem:
1194         destroy_mount_options(pctx->opts);
1195         ceph_destroy_options(pctx->copts);
1196         kfree(pctx);
1197         return -ENOMEM;
1198 }
1199
1200 static void ceph_kill_sb(struct super_block *s)
1201 {
1202         struct ceph_fs_client *fsc = ceph_sb_to_client(s);
1203         dev_t dev = s->s_dev;
1204
1205         dout("kill_sb %p\n", s);
1206
1207         ceph_mdsc_pre_umount(fsc->mdsc);
1208         flush_fs_workqueues(fsc);
1209
1210         generic_shutdown_super(s);
1211
1212         fsc->client->extra_mon_dispatch = NULL;
1213         ceph_fs_debugfs_cleanup(fsc);
1214
1215         ceph_fscache_unregister_fs(fsc);
1216
1217         destroy_fs_client(fsc);
1218         free_anon_bdev(dev);
1219 }
1220
1221 static struct file_system_type ceph_fs_type = {
1222         .owner          = THIS_MODULE,
1223         .name           = "ceph",
1224         .init_fs_context = ceph_init_fs_context,
1225         .kill_sb        = ceph_kill_sb,
1226         .fs_flags       = FS_RENAME_DOES_D_MOVE,
1227 };
1228 MODULE_ALIAS_FS("ceph");
1229
1230 int ceph_force_reconnect(struct super_block *sb)
1231 {
1232         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1233         int err = 0;
1234
1235         ceph_umount_begin(sb);
1236
1237         /* Make sure all page caches get invalidated.
1238          * see remove_session_caps_cb() */
1239         flush_workqueue(fsc->inode_wq);
1240
1241         /* In case that we were blacklisted. This also reset
1242          * all mon/osd connections */
1243         ceph_reset_client_addr(fsc->client);
1244
1245         ceph_osdc_clear_abort_err(&fsc->client->osdc);
1246
1247         fsc->blacklisted = false;
1248         fsc->mount_state = CEPH_MOUNT_MOUNTED;
1249
1250         if (sb->s_root) {
1251                 err = __ceph_do_getattr(d_inode(sb->s_root), NULL,
1252                                         CEPH_STAT_CAP_INODE, true);
1253         }
1254         return err;
1255 }
1256
1257 static int __init init_ceph(void)
1258 {
1259         int ret = init_caches();
1260         if (ret)
1261                 goto out;
1262
1263         ceph_flock_init();
1264         ret = register_filesystem(&ceph_fs_type);
1265         if (ret)
1266                 goto out_caches;
1267
1268         pr_info("loaded (mds proto %d)\n", CEPH_MDSC_PROTOCOL);
1269
1270         return 0;
1271
1272 out_caches:
1273         destroy_caches();
1274 out:
1275         return ret;
1276 }
1277
1278 static void __exit exit_ceph(void)
1279 {
1280         dout("exit_ceph\n");
1281         unregister_filesystem(&ceph_fs_type);
1282         destroy_caches();
1283 }
1284
1285 module_init(init_ceph);
1286 module_exit(exit_ceph);
1287
1288 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
1289 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
1290 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
1291 MODULE_DESCRIPTION("Ceph filesystem for Linux");
1292 MODULE_LICENSE("GPL");