fs/ceph/super.c

   1
   2 #include "ceph_debug.h"
   3
   4 #include <linux/backing-dev.h>
   5 #include <linux/fs.h>
   6 #include <linux/inet.h>
   7 #include <linux/in6.h>
   8 #include <linux/module.h>
   9 #include <linux/mount.h>
  10 #include <linux/parser.h>
  11 #include <linux/rwsem.h>
  12 #include <linux/sched.h>
  13 #include <linux/seq_file.h>
  14 #include <linux/statfs.h>
  15 #include <linux/string.h>
  16 #include <linux/version.h>
  17 #include <linux/vmalloc.h>
  18
  19 #include "decode.h"
  20 #include "super.h"
  21 #include "mon_client.h"
  22 #include "auth.h"
  23
  24 /*
  25  * Ceph superblock operations
  26  *
  27  * Handle the basics of mounting, unmounting.
  28  */
  29
  30
  31 /*
  32  * find filename portion of a path (/foo/bar/baz -> baz)
  33  */
  34 const char *ceph_file_part(const char *s, int len)
  35 {
  36         const char *e = s + len;
  37
  38         while (e != s && *(e-1) != '/')
  39                 e--;
  40         return e;
  41 }
  42
  43
  44 /*
  45  * super ops
  46  */
  47 static void ceph_put_super(struct super_block *s)
  48 {
  49         struct ceph_client *cl = ceph_client(s);
  50
  51         dout("put_super\n");
  52         ceph_mdsc_close_sessions(&cl->mdsc);
  53         return;
  54 }
  55
  56 static int ceph_statfs(struct dentry *dentry, struct kstatfs *buf)
  57 {
  58         struct ceph_client *client = ceph_inode_to_client(dentry->d_inode);
  59         struct ceph_monmap *monmap = client->monc.monmap;
  60         struct ceph_statfs st;
  61         u64 fsid;
  62         int err;
  63
  64         dout("statfs\n");
  65         err = ceph_monc_do_statfs(&client->monc, &st);
  66         if (err < 0)
  67                 return err;
  68
  69         /* fill in kstatfs */
  70         buf->f_type = CEPH_SUPER_MAGIC;  /* ?? */
  71
  72         /*
  73          * express utilization in terms of large blocks to avoid
  74          * overflow on 32-bit machines.
  75          */
  76         buf->f_bsize = 1 << CEPH_BLOCK_SHIFT;
  77         buf->f_blocks = le64_to_cpu(st.kb) >> (CEPH_BLOCK_SHIFT-10);
  78         buf->f_bfree = (le64_to_cpu(st.kb) - le64_to_cpu(st.kb_used)) >>
  79                 (CEPH_BLOCK_SHIFT-10);
  80         buf->f_bavail = le64_to_cpu(st.kb_avail) >> (CEPH_BLOCK_SHIFT-10);
  81
  82         buf->f_files = le64_to_cpu(st.num_objects);
  83         buf->f_ffree = -1;
  84         buf->f_namelen = PATH_MAX;
  85         buf->f_frsize = PAGE_CACHE_SIZE;
  86
  87         /* leave fsid little-endian, regardless of host endianness */
  88         fsid = *(u64 *)(&monmap->fsid) ^ *((u64 *)&monmap->fsid + 1);
  89         buf->f_fsid.val[0] = fsid & 0xffffffff;
  90         buf->f_fsid.val[1] = fsid >> 32;
  91
  92         return 0;
  93 }
  94
  95
  96 static int ceph_syncfs(struct super_block *sb, int wait)
  97 {
  98         dout("sync_fs %d\n", wait);
  99         ceph_osdc_sync(&ceph_client(sb)->osdc);
 100         ceph_mdsc_sync(&ceph_client(sb)->mdsc);
 101         dout("sync_fs %d done\n", wait);
 102         return 0;
 103 }
 104
 105
 106 /**
 107  * ceph_show_options - Show mount options in /proc/mounts
 108  * @m: seq_file to write to
 109  * @mnt: mount descriptor
 110  */
 111 static int ceph_show_options(struct seq_file *m, struct vfsmount *mnt)
 112 {
 113         struct ceph_client *client = ceph_sb_to_client(mnt->mnt_sb);
 114         struct ceph_mount_args *args = client->mount_args;
 115
 116         if (args->flags & CEPH_OPT_FSID)
 117                 seq_printf(m, ",fsidmajor=%llu,fsidminor%llu",
 118                            le64_to_cpu(*(__le64 *)&args->fsid.fsid[0]),
 119                            le64_to_cpu(*(__le64 *)&args->fsid.fsid[8]));
 120         if (args->flags & CEPH_OPT_NOSHARE)
 121                 seq_puts(m, ",noshare");
 122         if (args->flags & CEPH_OPT_DIRSTAT)
 123                 seq_puts(m, ",dirstat");
 124         if ((args->flags & CEPH_OPT_RBYTES) == 0)
 125                 seq_puts(m, ",norbytes");
 126         if (args->flags & CEPH_OPT_NOCRC)
 127                 seq_puts(m, ",nocrc");
 128         if (args->flags & CEPH_OPT_NOASYNCREADDIR)
 129                 seq_puts(m, ",noasyncreaddir");
 130         if (strcmp(args->snapdir_name, CEPH_SNAPDIRNAME_DEFAULT))
 131                 seq_printf(m, ",snapdirname=%s", args->snapdir_name);
 132         if (args->name)
 133                 seq_printf(m, ",name=%s", args->name);
 134         if (args->secret)
 135                 seq_puts(m, ",secret=<hidden>");
 136         return 0;
 137 }
 138
 139 /*
 140  * caches
 141  */
 142 struct kmem_cache *ceph_inode_cachep;
 143 struct kmem_cache *ceph_cap_cachep;
 144 struct kmem_cache *ceph_dentry_cachep;
 145 struct kmem_cache *ceph_file_cachep;
 146
 147 static void ceph_inode_init_once(void *foo)
 148 {
 149         struct ceph_inode_info *ci = foo;
 150         inode_init_once(&ci->vfs_inode);
 151 }
 152
 153 static int __init init_caches(void)
 154 {
 155         ceph_inode_cachep = kmem_cache_create("ceph_inode_info",
 156                                       sizeof(struct ceph_inode_info),
 157                                       __alignof__(struct ceph_inode_info),
 158                                       (SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD),
 159                                       ceph_inode_init_once);
 160         if (ceph_inode_cachep == NULL)
 161                 return -ENOMEM;
 162
 163         ceph_cap_cachep = KMEM_CACHE(ceph_cap,
 164                                      SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 165         if (ceph_cap_cachep == NULL)
 166                 goto bad_cap;
 167
 168         ceph_dentry_cachep = KMEM_CACHE(ceph_dentry_info,
 169                                         SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 170         if (ceph_dentry_cachep == NULL)
 171                 goto bad_dentry;
 172
 173         ceph_file_cachep = KMEM_CACHE(ceph_file_info,
 174                                       SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD);
 175         if (ceph_file_cachep == NULL)
 176                 goto bad_file;
 177
 178         return 0;
 179
 180 bad_file:
 181         kmem_cache_destroy(ceph_dentry_cachep);
 182 bad_dentry:
 183         kmem_cache_destroy(ceph_cap_cachep);
 184 bad_cap:
 185         kmem_cache_destroy(ceph_inode_cachep);
 186         return -ENOMEM;
 187 }
 188
 189 static void destroy_caches(void)
 190 {
 191         kmem_cache_destroy(ceph_inode_cachep);
 192         kmem_cache_destroy(ceph_cap_cachep);
 193         kmem_cache_destroy(ceph_dentry_cachep);
 194         kmem_cache_destroy(ceph_file_cachep);
 195 }
 196
 197
 198 /*
 199  * ceph_umount_begin - initiate forced umount.  Tear down down the
 200  * mount, skipping steps that may hang while waiting for server(s).
 201  */
 202 static void ceph_umount_begin(struct super_block *sb)
 203 {
 204         struct ceph_client *client = ceph_sb_to_client(sb);
 205
 206         dout("ceph_umount_begin - starting forced umount\n");
 207         if (!client)
 208                 return;
 209         client->mount_state = CEPH_MOUNT_SHUTDOWN;
 210         return;
 211 }
 212
 213 static const struct super_operations ceph_super_ops = {
 214         .alloc_inode    = ceph_alloc_inode,
 215         .destroy_inode  = ceph_destroy_inode,
 216         .write_inode    = ceph_write_inode,
 217         .sync_fs        = ceph_syncfs,
 218         .put_super      = ceph_put_super,
 219         .show_options   = ceph_show_options,
 220         .statfs         = ceph_statfs,
 221         .umount_begin   = ceph_umount_begin,
 222 };
 223
 224
 225 const char *ceph_msg_type_name(int type)
 226 {
 227         switch (type) {
 228         case CEPH_MSG_SHUTDOWN: return "shutdown";
 229         case CEPH_MSG_PING: return "ping";
 230         case CEPH_MSG_AUTH: return "auth";
 231         case CEPH_MSG_AUTH_REPLY: return "auth_reply";
 232         case CEPH_MSG_MON_MAP: return "mon_map";
 233         case CEPH_MSG_MON_GET_MAP: return "mon_get_map";
 234         case CEPH_MSG_MON_SUBSCRIBE: return "mon_subscribe";
 235         case CEPH_MSG_MON_SUBSCRIBE_ACK: return "mon_subscribe_ack";
 236         case CEPH_MSG_STATFS: return "statfs";
 237         case CEPH_MSG_STATFS_REPLY: return "statfs_reply";
 238         case CEPH_MSG_MDS_MAP: return "mds_map";
 239         case CEPH_MSG_CLIENT_SESSION: return "client_session";
 240         case CEPH_MSG_CLIENT_RECONNECT: return "client_reconnect";
 241         case CEPH_MSG_CLIENT_REQUEST: return "client_request";
 242         case CEPH_MSG_CLIENT_REQUEST_FORWARD: return "client_request_forward";
 243         case CEPH_MSG_CLIENT_REPLY: return "client_reply";
 244         case CEPH_MSG_CLIENT_CAPS: return "client_caps";
 245         case CEPH_MSG_CLIENT_CAPRELEASE: return "client_cap_release";
 246         case CEPH_MSG_CLIENT_SNAP: return "client_snap";
 247         case CEPH_MSG_CLIENT_LEASE: return "client_lease";
 248         case CEPH_MSG_OSD_MAP: return "osd_map";
 249         case CEPH_MSG_OSD_OP: return "osd_op";
 250         case CEPH_MSG_OSD_OPREPLY: return "osd_opreply";
 251         default: return "unknown";
 252         }
 253 }
 254
 255
 256 /*
 257  * mount options
 258  */
 259 enum {
 260         Opt_fsidmajor,
 261         Opt_fsidminor,
 262         Opt_monport,
 263         Opt_wsize,
 264         Opt_rsize,
 265         Opt_osdtimeout,
 266         Opt_mount_timeout,
 267         Opt_caps_wanted_delay_min,
 268         Opt_caps_wanted_delay_max,
 269         Opt_readdir_max_entries,
 270         Opt_last_int,
 271         /* int args above */
 272         Opt_snapdirname,
 273         Opt_name,
 274         Opt_secret,
 275         Opt_last_string,
 276         /* string args above */
 277         Opt_ip,
 278         Opt_noshare,
 279         Opt_dirstat,
 280         Opt_nodirstat,
 281         Opt_rbytes,
 282         Opt_norbytes,
 283         Opt_nocrc,
 284         Opt_noasyncreaddir,
 285 };
 286
 287 static match_table_t arg_tokens = {
 288         {Opt_fsidmajor, "fsidmajor=%ld"},
 289         {Opt_fsidminor, "fsidminor=%ld"},
 290         {Opt_monport, "monport=%d"},
 291         {Opt_wsize, "wsize=%d"},
 292         {Opt_rsize, "rsize=%d"},
 293         {Opt_osdtimeout, "osdtimeout=%d"},
 294         {Opt_mount_timeout, "mount_timeout=%d"},
 295         {Opt_caps_wanted_delay_min, "caps_wanted_delay_min=%d"},
 296         {Opt_caps_wanted_delay_max, "caps_wanted_delay_max=%d"},
 297         {Opt_readdir_max_entries, "readdir_max_entries=%d"},
 298         /* int args above */
 299         {Opt_snapdirname, "snapdirname=%s"},
 300         {Opt_name, "name=%s"},
 301         {Opt_secret, "secret=%s"},
 302         /* string args above */
 303         {Opt_ip, "ip=%s"},
 304         {Opt_noshare, "noshare"},
 305         {Opt_dirstat, "dirstat"},
 306         {Opt_nodirstat, "nodirstat"},
 307         {Opt_rbytes, "rbytes"},
 308         {Opt_norbytes, "norbytes"},
 309         {Opt_nocrc, "nocrc"},
 310         {Opt_noasyncreaddir, "noasyncreaddir"},
 311         {-1, NULL}
 312 };
 313
 314
 315 static struct ceph_mount_args *parse_mount_args(int flags, char *options,
 316                                                 const char *dev_name,
 317                                                 const char **path)
 318 {
 319         struct ceph_mount_args *args;
 320         const char *c;
 321         int err = -ENOMEM;
 322         substring_t argstr[MAX_OPT_ARGS];
 323
 324         args = kzalloc(sizeof(*args), GFP_KERNEL);
 325         if (!args)
 326                 return ERR_PTR(-ENOMEM);
 327         args->mon_addr = kcalloc(CEPH_MAX_MON, sizeof(*args->mon_addr),
 328                                  GFP_KERNEL);
 329         if (!args->mon_addr)
 330                 goto out;
 331
 332         dout("parse_mount_args %p, dev_name '%s'\n", args, dev_name);
 333
 334         /* start with defaults */
 335         args->sb_flags = flags;
 336         args->flags = CEPH_OPT_DEFAULT;
 337         args->osd_timeout = 5;    /* seconds */
 338         args->mount_timeout = CEPH_MOUNT_TIMEOUT_DEFAULT; /* seconds */
 339         args->caps_wanted_delay_min = CEPH_CAPS_WANTED_DELAY_MIN_DEFAULT;
 340         args->caps_wanted_delay_max = CEPH_CAPS_WANTED_DELAY_MAX_DEFAULT;
 341         args->rsize = CEPH_MOUNT_RSIZE_DEFAULT;
 342         args->snapdir_name = kstrdup(CEPH_SNAPDIRNAME_DEFAULT, GFP_KERNEL);
 343         args->cap_release_safety = CEPH_CAPS_PER_RELEASE * 4;
 344         args->max_readdir = 1024;
 345
 346         /* ip1[:port1][,ip2[:port2]...]:/subdir/in/fs */
 347         err = -EINVAL;
 348         if (!dev_name)
 349                 goto out;
 350         *path = strstr(dev_name, ":/");
 351         if (*path == NULL) {
 352                 pr_err("device name is missing path (no :/ in %s)\n",
 353                        dev_name);
 354                 goto out;
 355         }
 356
 357         /* get mon ip(s) */
 358         err = ceph_parse_ips(dev_name, *path, args->mon_addr,
 359                              CEPH_MAX_MON, &args->num_mon);
 360         if (err < 0)
 361                 goto out;
 362
 363         /* path on server */
 364         *path += 2;
 365         dout("server path '%s'\n", *path);
 366
 367         /* parse mount options */
 368         while ((c = strsep(&options, ",")) != NULL) {
 369                 int token, intval, ret;
 370                 if (!*c)
 371                         continue;
 372                 err = -EINVAL;
 373                 token = match_token((char *)c, arg_tokens, argstr);
 374                 if (token < 0) {
 375                         pr_err("bad mount option at '%s'\n", c);
 376                         goto out;
 377                 }
 378                 if (token < Opt_last_int) {
 379                         ret = match_int(&argstr[0], &intval);
 380                         if (ret < 0) {
 381                                 pr_err("bad mount option arg (not int) "
 382                                        "at '%s'\n", c);
 383                                 continue;
 384                         }
 385                         dout("got int token %d val %d\n", token, intval);
 386                 } else if (token > Opt_last_int && token < Opt_last_string) {
 387                         dout("got string token %d val %s\n", token,
 388                              argstr[0].from);
 389                 } else {
 390                         dout("got token %d\n", token);
 391                 }
 392                 switch (token) {
 393                 case Opt_fsidmajor:
 394                         *(__le64 *)&args->fsid.fsid[0] = cpu_to_le64(intval);
 395                         break;
 396                 case Opt_fsidminor:
 397                         *(__le64 *)&args->fsid.fsid[8] = cpu_to_le64(intval);
 398                         break;
 399                 case Opt_ip:
 400                         err = ceph_parse_ips(argstr[0].from,
 401                                              argstr[0].to,
 402                                              &args->my_addr,
 403                                              1, NULL);
 404                         if (err < 0)
 405                                 goto out;
 406                         args->flags |= CEPH_OPT_MYIP;
 407                         break;
 408
 409                 case Opt_snapdirname:
 410                         kfree(args->snapdir_name);
 411                         args->snapdir_name = kstrndup(argstr[0].from,
 412                                               argstr[0].to-argstr[0].from,
 413                                               GFP_KERNEL);
 414                         break;
 415                 case Opt_name:
 416                         args->name = kstrndup(argstr[0].from,
 417                                               argstr[0].to-argstr[0].from,
 418                                               GFP_KERNEL);
 419                         break;
 420                 case Opt_secret:
 421                         args->secret = kstrndup(argstr[0].from,
 422                                                 argstr[0].to-argstr[0].from,
 423                                                 GFP_KERNEL);
 424                         break;
 425
 426                         /* misc */
 427                 case Opt_wsize:
 428                         args->wsize = intval;
 429                         break;
 430                 case Opt_rsize:
 431                         args->rsize = intval;
 432                         break;
 433                 case Opt_osdtimeout:
 434                         args->osd_timeout = intval;
 435                         break;
 436                 case Opt_mount_timeout:
 437                         args->mount_timeout = intval;
 438                         break;
 439                 case Opt_caps_wanted_delay_min:
 440                         args->caps_wanted_delay_min = intval;
 441                         break;
 442                 case Opt_caps_wanted_delay_max:
 443                         args->caps_wanted_delay_max = intval;
 444                         break;
 445                 case Opt_readdir_max_entries:
 446                         args->max_readdir = intval;
 447                         break;
 448
 449                 case Opt_noshare:
 450                         args->flags |= CEPH_OPT_NOSHARE;
 451                         break;
 452
 453                 case Opt_dirstat:
 454                         args->flags |= CEPH_OPT_DIRSTAT;
 455                         break;
 456                 case Opt_nodirstat:
 457                         args->flags &= ~CEPH_OPT_DIRSTAT;
 458                         break;
 459                 case Opt_rbytes:
 460                         args->flags |= CEPH_OPT_RBYTES;
 461                         break;
 462                 case Opt_norbytes:
 463                         args->flags &= ~CEPH_OPT_RBYTES;
 464                         break;
 465                 case Opt_nocrc:
 466                         args->flags |= CEPH_OPT_NOCRC;
 467                         break;
 468                 case Opt_noasyncreaddir:
 469                         args->flags |= CEPH_OPT_NOASYNCREADDIR;
 470                         break;
 471
 472                 default:
 473                         BUG_ON(token);
 474                 }
 475         }
 476         return args;
 477
 478 out:
 479         kfree(args->mon_addr);
 480         kfree(args);
 481         return ERR_PTR(err);
 482 }
 483
 484 static void destroy_mount_args(struct ceph_mount_args *args)
 485 {
 486         dout("destroy_mount_args %p\n", args);
 487         kfree(args->snapdir_name);
 488         args->snapdir_name = NULL;
 489         kfree(args->name);
 490         args->name = NULL;
 491         kfree(args->secret);
 492         args->secret = NULL;
 493         kfree(args);
 494 }
 495
 496 /*
 497  * create a fresh client instance
 498  */
 499 static struct ceph_client *ceph_create_client(struct ceph_mount_args *args)
 500 {
 501         struct ceph_client *client;
 502         int err = -ENOMEM;
 503
 504         client = kzalloc(sizeof(*client), GFP_KERNEL);
 505         if (client == NULL)
 506                 return ERR_PTR(-ENOMEM);
 507
 508         mutex_init(&client->mount_mutex);
 509
 510         init_waitqueue_head(&client->mount_wq);
 511
 512         client->sb = NULL;
 513         client->mount_state = CEPH_MOUNT_MOUNTING;
 514         client->mount_args = args;
 515
 516         client->msgr = NULL;
 517
 518         client->mount_err = 0;
 519
 520         err = bdi_init(&client->backing_dev_info);
 521         if (err < 0)
 522                 goto fail;
 523
 524         err = -ENOMEM;
 525         client->wb_wq = create_workqueue("ceph-writeback");
 526         if (client->wb_wq == NULL)
 527                 goto fail_bdi;
 528         client->pg_inv_wq = create_singlethread_workqueue("ceph-pg-invalid");
 529         if (client->pg_inv_wq == NULL)
 530                 goto fail_wb_wq;
 531         client->trunc_wq = create_singlethread_workqueue("ceph-trunc");
 532         if (client->trunc_wq == NULL)
 533                 goto fail_pg_inv_wq;
 534
 535         /* set up mempools */
 536         err = -ENOMEM;
 537         client->wb_pagevec_pool = mempool_create_kmalloc_pool(10,
 538                               client->mount_args->wsize >> PAGE_CACHE_SHIFT);
 539         if (!client->wb_pagevec_pool)
 540                 goto fail_trunc_wq;
 541
 542
 543         /* subsystems */
 544         err = ceph_monc_init(&client->monc, client);
 545         if (err < 0)
 546                 goto fail_mempool;
 547         err = ceph_osdc_init(&client->osdc, client);
 548         if (err < 0)
 549                 goto fail_monc;
 550         err = ceph_mdsc_init(&client->mdsc, client);
 551         if (err < 0)
 552                 goto fail_osdc;
 553         return client;
 554
 555 fail_osdc:
 556         ceph_osdc_stop(&client->osdc);
 557 fail_monc:
 558         ceph_monc_stop(&client->monc);
 559 fail_mempool:
 560         mempool_destroy(client->wb_pagevec_pool);
 561 fail_trunc_wq:
 562         destroy_workqueue(client->trunc_wq);
 563 fail_pg_inv_wq:
 564         destroy_workqueue(client->pg_inv_wq);
 565 fail_wb_wq:
 566         destroy_workqueue(client->wb_wq);
 567 fail_bdi:
 568         bdi_destroy(&client->backing_dev_info);
 569 fail:
 570         kfree(client);
 571         return ERR_PTR(err);
 572 }
 573
 574 static void ceph_destroy_client(struct ceph_client *client)
 575 {
 576         dout("destroy_client %p\n", client);
 577
 578         /* unmount */
 579         ceph_mdsc_stop(&client->mdsc);
 580         ceph_monc_stop(&client->monc);
 581         ceph_osdc_stop(&client->osdc);
 582
 583         ceph_debugfs_client_cleanup(client);
 584         destroy_workqueue(client->wb_wq);
 585         destroy_workqueue(client->pg_inv_wq);
 586         destroy_workqueue(client->trunc_wq);
 587
 588         if (client->msgr)
 589                 ceph_messenger_destroy(client->msgr);
 590         mempool_destroy(client->wb_pagevec_pool);
 591
 592         destroy_mount_args(client->mount_args);
 593
 594         kfree(client);
 595         dout("destroy_client %p done\n", client);
 596 }
 597
 598 /*
 599  * Initially learn our fsid, or verify an fsid matches.
 600  */
 601 int ceph_check_fsid(struct ceph_client *client, struct ceph_fsid *fsid)
 602 {
 603         if (client->have_fsid) {
 604                 if (ceph_fsid_compare(&client->fsid, fsid)) {
 605                         pr_err("bad fsid, had " FSID_FORMAT " got " FSID_FORMAT,
 606                                PR_FSID(&client->fsid), PR_FSID(fsid));
 607                         return -1;
 608                 }
 609         } else {
 610                 pr_info("client%lld fsid " FSID_FORMAT "\n",
 611                         client->monc.auth->global_id, PR_FSID(fsid));
 612                 memcpy(&client->fsid, fsid, sizeof(*fsid));
 613                 ceph_debugfs_client_init(client);
 614                 client->have_fsid = true;
 615         }
 616         return 0;
 617 }
 618
 619 /*
 620  * true if we have the mon map (and have thus joined the cluster)
 621  */
 622 static int have_mon_map(struct ceph_client *client)
 623 {
 624         return client->monc.monmap && client->monc.monmap->epoch;
 625 }
 626
 627 /*
 628  * Bootstrap mount by opening the root directory.  Note the mount
 629  * @started time from caller, and time out if this takes too long.
 630  */
 631 static struct dentry *open_root_dentry(struct ceph_client *client,
 632                                        const char *path,
 633                                        unsigned long started)
 634 {
 635         struct ceph_mds_client *mdsc = &client->mdsc;
 636         struct ceph_mds_request *req = NULL;
 637         int err;
 638         struct dentry *root;
 639
 640         /* open dir */
 641         dout("open_root_inode opening '%s'\n", path);
 642         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
 643         if (IS_ERR(req))
 644                 return ERR_PTR(PTR_ERR(req));
 645         req->r_path1 = kstrdup(path, GFP_NOFS);
 646         req->r_ino1.ino = CEPH_INO_ROOT;
 647         req->r_ino1.snap = CEPH_NOSNAP;
 648         req->r_started = started;
 649         req->r_timeout = client->mount_args->mount_timeout * HZ;
 650         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 651         req->r_num_caps = 2;
 652         err = ceph_mdsc_do_request(mdsc, NULL, req);
 653         if (err == 0) {
 654                 dout("open_root_inode success\n");
 655                 if (ceph_ino(req->r_target_inode) == CEPH_INO_ROOT &&
 656                     client->sb->s_root == NULL)
 657                         root = d_alloc_root(req->r_target_inode);
 658                 else
 659                         root = d_obtain_alias(req->r_target_inode);
 660                 req->r_target_inode = NULL;
 661                 dout("open_root_inode success, root dentry is %p\n", root);
 662         } else {
 663                 root = ERR_PTR(err);
 664         }
 665         ceph_mdsc_put_request(req);
 666         return root;
 667 }
 668
 669 /*
 670  * mount: join the ceph cluster, and open root directory.
 671  */
 672 static int ceph_mount(struct ceph_client *client, struct vfsmount *mnt,
 673                       const char *path)
 674 {
 675         struct ceph_entity_addr *myaddr = NULL;
 676         int err;
 677         unsigned long timeout = client->mount_args->mount_timeout * HZ;
 678         unsigned long started = jiffies;  /* note the start time */
 679         struct dentry *root;
 680
 681         dout("mount start\n");
 682         mutex_lock(&client->mount_mutex);
 683
 684         /* initialize the messenger */
 685         if (client->msgr == NULL) {
 686                 if (ceph_test_opt(client, MYIP))
 687                         myaddr = &client->mount_args->my_addr;
 688                 client->msgr = ceph_messenger_create(myaddr);
 689                 if (IS_ERR(client->msgr)) {
 690                         err = PTR_ERR(client->msgr);
 691                         client->msgr = NULL;
 692                         goto out;
 693                 }
 694                 client->msgr->nocrc = ceph_test_opt(client, NOCRC);
 695         }
 696
 697         /* open session, and wait for mon, mds, and osd maps */
 698         err = ceph_monc_open_session(&client->monc);
 699         if (err < 0)
 700                 goto out;
 701
 702         while (!have_mon_map(client)) {
 703                 err = -EIO;
 704                 if (timeout && time_after_eq(jiffies, started + timeout))
 705                         goto out;
 706
 707                 /* wait */
 708                 dout("mount waiting for mon_map\n");
 709                 err = wait_event_interruptible_timeout(client->mount_wq, /* FIXME */
 710                                have_mon_map(client) || (client->mount_err < 0),
 711                                timeout);
 712                 if (err == -EINTR || err == -ERESTARTSYS)
 713                         goto out;
 714                 if (client->mount_err < 0) {
 715                         err = client->mount_err;
 716                         goto out;
 717                 }
 718         }
 719
 720         dout("mount opening root\n");
 721         root = open_root_dentry(client, "", started);
 722         if (IS_ERR(root)) {
 723                 err = PTR_ERR(root);
 724                 goto out;
 725         }
 726         if (client->sb->s_root)
 727                 dput(root);
 728         else
 729                 client->sb->s_root = root;
 730
 731         if (path[0] == 0) {
 732                 dget(root);
 733         } else {
 734                 dout("mount opening base mountpoint\n");
 735                 root = open_root_dentry(client, path, started);
 736                 if (IS_ERR(root)) {
 737                         err = PTR_ERR(root);
 738                         dput(client->sb->s_root);
 739                         client->sb->s_root = NULL;
 740                         goto out;
 741                 }
 742         }
 743
 744         mnt->mnt_root = root;
 745         mnt->mnt_sb = client->sb;
 746
 747         client->mount_state = CEPH_MOUNT_MOUNTED;
 748         dout("mount success\n");
 749         err = 0;
 750
 751 out:
 752         mutex_unlock(&client->mount_mutex);
 753         return err;
 754 }
 755
 756 static int ceph_set_super(struct super_block *s, void *data)
 757 {
 758         struct ceph_client *client = data;
 759         int ret;
 760
 761         dout("set_super %p data %p\n", s, data);
 762
 763         s->s_flags = client->mount_args->sb_flags;
 764         s->s_maxbytes = 1ULL << 40;  /* temp value until we get mdsmap */
 765
 766         s->s_fs_info = client;
 767         client->sb = s;
 768
 769         s->s_op = &ceph_super_ops;
 770         s->s_export_op = &ceph_export_ops;
 771
 772         s->s_time_gran = 1000;  /* 1000 ns == 1 us */
 773
 774         ret = set_anon_super(s, NULL);  /* what is that second arg for? */
 775         if (ret != 0)
 776                 goto fail;
 777
 778         return ret;
 779
 780 fail:
 781         s->s_fs_info = NULL;
 782         client->sb = NULL;
 783         return ret;
 784 }
 785
 786 /*
 787  * share superblock if same fs AND options
 788  */
 789 static int ceph_compare_super(struct super_block *sb, void *data)
 790 {
 791         struct ceph_client *new = data;
 792         struct ceph_mount_args *args = new->mount_args;
 793         struct ceph_client *other = ceph_sb_to_client(sb);
 794         int i;
 795
 796         dout("ceph_compare_super %p\n", sb);
 797         if (args->flags & CEPH_OPT_FSID) {
 798                 if (ceph_fsid_compare(&args->fsid, &other->fsid)) {
 799                         dout("fsid doesn't match\n");
 800                         return 0;
 801                 }
 802         } else {
 803                 /* do we share (a) monitor? */
 804                 for (i = 0; i < new->monc.monmap->num_mon; i++)
 805                         if (ceph_monmap_contains(other->monc.monmap,
 806                                          &new->monc.monmap->mon_inst[i].addr))
 807                                 break;
 808                 if (i == new->monc.monmap->num_mon) {
 809                         dout("mon ip not part of monmap\n");
 810                         return 0;
 811                 }
 812                 dout("mon ip matches existing sb %p\n", sb);
 813         }
 814         if (args->sb_flags != other->mount_args->sb_flags) {
 815                 dout("flags differ\n");
 816                 return 0;
 817         }
 818         return 1;
 819 }
 820
 821 /*
 822  * construct our own bdi so we can control readahead, etc.
 823  */
 824 static int ceph_register_bdi(struct super_block *sb, struct ceph_client *client)
 825 {
 826         int err;
 827
 828         sb->s_bdi = &client->backing_dev_info;
 829
 830         /* set ra_pages based on rsize mount option? */
 831         if (client->mount_args->rsize >= PAGE_CACHE_SIZE)
 832                 client->backing_dev_info.ra_pages =
 833                         (client->mount_args->rsize + PAGE_CACHE_SIZE - 1)
 834                         >> PAGE_SHIFT;
 835         err = bdi_register_dev(&client->backing_dev_info, sb->s_dev);
 836         return err;
 837 }
 838
 839 static int ceph_get_sb(struct file_system_type *fs_type,
 840                        int flags, const char *dev_name, void *data,
 841                        struct vfsmount *mnt)
 842 {
 843         struct super_block *sb;
 844         struct ceph_client *client;
 845         int err;
 846         int (*compare_super)(struct super_block *, void *) = ceph_compare_super;
 847         const char *path = NULL;
 848         struct ceph_mount_args *args;
 849
 850         dout("ceph_get_sb\n");
 851         args = parse_mount_args(flags, data, dev_name, &path);
 852         if (IS_ERR(args)) {
 853                 err = PTR_ERR(args);
 854                 goto out_final;
 855         }
 856
 857         /* create client (which we may/may not use) */
 858         client = ceph_create_client(args);
 859         if (IS_ERR(client)) {
 860                 err = PTR_ERR(client);
 861                 goto out_final;
 862         }
 863
 864         if (client->mount_args->flags & CEPH_OPT_NOSHARE)
 865                 compare_super = NULL;
 866         sb = sget(fs_type, compare_super, ceph_set_super, client);
 867         if (IS_ERR(sb)) {
 868                 err = PTR_ERR(sb);
 869                 goto out;
 870         }
 871
 872         if (ceph_client(sb) != client) {
 873                 ceph_destroy_client(client);
 874                 client = ceph_client(sb);
 875                 dout("get_sb got existing client %p\n", client);
 876         } else {
 877                 dout("get_sb using new client %p\n", client);
 878                 err = ceph_register_bdi(sb, client);
 879                 if (err < 0)
 880                         goto out_splat;
 881         }
 882
 883         err = ceph_mount(client, mnt, path);
 884         if (err < 0)
 885                 goto out_splat;
 886         dout("root %p inode %p ino %llx.%llx\n", mnt->mnt_root,
 887              mnt->mnt_root->d_inode, ceph_vinop(mnt->mnt_root->d_inode));
 888         return 0;
 889
 890 out_splat:
 891         ceph_mdsc_close_sessions(&client->mdsc);
 892         up_write(&sb->s_umount);
 893         deactivate_super(sb);
 894         goto out_final;
 895
 896 out:
 897         ceph_destroy_client(client);
 898 out_final:
 899         dout("ceph_get_sb fail %d\n", err);
 900         return err;
 901 }
 902
 903 static void ceph_kill_sb(struct super_block *s)
 904 {
 905         struct ceph_client *client = ceph_sb_to_client(s);
 906         dout("kill_sb %p\n", s);
 907         ceph_mdsc_pre_umount(&client->mdsc);
 908         kill_anon_super(s);    /* will call put_super after sb is r/o */
 909         bdi_unregister(&client->backing_dev_info);
 910         bdi_destroy(&client->backing_dev_info);
 911         ceph_destroy_client(client);
 912 }
 913
 914 static struct file_system_type ceph_fs_type = {
 915         .owner          = THIS_MODULE,
 916         .name           = "ceph",
 917         .get_sb         = ceph_get_sb,
 918         .kill_sb        = ceph_kill_sb,
 919         .fs_flags       = FS_RENAME_DOES_D_MOVE,
 920 };
 921
 922 #define _STRINGIFY(x) #x
 923 #define STRINGIFY(x) _STRINGIFY(x)
 924
 925 static int __init init_ceph(void)
 926 {
 927         int ret = 0;
 928
 929         ret = ceph_debugfs_init();
 930         if (ret < 0)
 931                 goto out;
 932
 933         ret = ceph_msgr_init();
 934         if (ret < 0)
 935                 goto out_debugfs;
 936
 937         ret = init_caches();
 938         if (ret)
 939                 goto out_msgr;
 940
 941         ceph_caps_init();
 942
 943         ret = register_filesystem(&ceph_fs_type);
 944         if (ret)
 945                 goto out_icache;
 946
 947         pr_info("loaded %d.%d.%d (mon/mds/osd proto %d/%d/%d)\n",
 948                 CEPH_VERSION_MAJOR, CEPH_VERSION_MINOR, CEPH_VERSION_PATCH,
 949                 CEPH_MONC_PROTOCOL, CEPH_MDSC_PROTOCOL, CEPH_OSDC_PROTOCOL);
 950         return 0;
 951
 952 out_icache:
 953         destroy_caches();
 954 out_msgr:
 955         ceph_msgr_exit();
 956 out_debugfs:
 957         ceph_debugfs_cleanup();
 958 out:
 959         return ret;
 960 }
 961
 962 static void __exit exit_ceph(void)
 963 {
 964         dout("exit_ceph\n");
 965         unregister_filesystem(&ceph_fs_type);
 966         ceph_caps_finalize();
 967         destroy_caches();
 968         ceph_msgr_exit();
 969         ceph_debugfs_cleanup();
 970 }
 971
 972 module_init(init_ceph);
 973 module_exit(exit_ceph);
 974
 975 MODULE_AUTHOR("Sage Weil <sage@newdream.net>");
 976 MODULE_AUTHOR("Yehuda Sadeh <yehuda@hq.newdream.net>");
 977 MODULE_AUTHOR("Patience Warnick <patience@newdream.net>");
 978 MODULE_DESCRIPTION("Ceph filesystem for Linux");
 979 MODULE_LICENSE("GPL");