kernel/fs/ceph/dir.c

   1 #include <linux/ceph/ceph_debug.h>
   2
   3 #include <linux/spinlock.h>
   4 #include <linux/fs_struct.h>
   5 #include <linux/namei.h>
   6 #include <linux/slab.h>
   7 #include <linux/sched.h>
   8
   9 #include "super.h"
  10 #include "mds_client.h"
  11
  12 /*
  13  * Directory operations: readdir, lookup, create, link, unlink,
  14  * rename, etc.
  15  */
  16
  17 /*
  18  * Ceph MDS operations are specified in terms of a base ino and
  19  * relative path.  Thus, the client can specify an operation on a
  20  * specific inode (e.g., a getattr due to fstat(2)), or as a path
  21  * relative to, say, the root directory.
  22  *
  23  * Normally, we limit ourselves to strict inode ops (no path component)
  24  * or dentry operations (a single path component relative to an ino).  The
  25  * exception to this is open_root_dentry(), which will open the mount
  26  * point by name.
  27  */
  28
  29 const struct dentry_operations ceph_dentry_ops;
  30
  31 /*
  32  * Initialize ceph dentry state.
  33  */
  34 int ceph_init_dentry(struct dentry *dentry)
  35 {
  36         struct ceph_dentry_info *di;
  37
  38         if (dentry->d_fsdata)
  39                 return 0;
  40
  41         di = kmem_cache_alloc(ceph_dentry_cachep, GFP_NOFS | __GFP_ZERO);
  42         if (!di)
  43                 return -ENOMEM;          /* oh well */
  44
  45         spin_lock(&dentry->d_lock);
  46         if (dentry->d_fsdata) {
  47                 /* lost a race */
  48                 kmem_cache_free(ceph_dentry_cachep, di);
  49                 goto out_unlock;
  50         }
  51
  52         if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_NOSNAP)
  53                 d_set_d_op(dentry, &ceph_dentry_ops);
  54         else if (ceph_snap(d_inode(dentry->d_parent)) == CEPH_SNAPDIR)
  55                 d_set_d_op(dentry, &ceph_snapdir_dentry_ops);
  56         else
  57                 d_set_d_op(dentry, &ceph_snap_dentry_ops);
  58
  59         di->dentry = dentry;
  60         di->lease_session = NULL;
  61         dentry->d_time = jiffies;
  62         /* avoid reordering d_fsdata setup so that the check above is safe */
  63         smp_mb();
  64         dentry->d_fsdata = di;
  65         ceph_dentry_lru_add(dentry);
  66 out_unlock:
  67         spin_unlock(&dentry->d_lock);
  68         return 0;
  69 }
  70
  71 struct inode *ceph_get_dentry_parent_inode(struct dentry *dentry)
  72 {
  73         struct inode *inode = NULL;
  74
  75         if (!dentry)
  76                 return NULL;
  77
  78         spin_lock(&dentry->d_lock);
  79         if (!IS_ROOT(dentry)) {
  80                 inode = d_inode(dentry->d_parent);
  81                 ihold(inode);
  82         }
  83         spin_unlock(&dentry->d_lock);
  84         return inode;
  85 }
  86
  87
  88 /*
  89  * for readdir, we encode the directory frag and offset within that
  90  * frag into f_pos.
  91  */
  92 static unsigned fpos_frag(loff_t p)
  93 {
  94         return p >> 32;
  95 }
  96 static unsigned fpos_off(loff_t p)
  97 {
  98         return p & 0xffffffff;
  99 }
 100
 101 static int fpos_cmp(loff_t l, loff_t r)
 102 {
 103         int v = ceph_frag_compare(fpos_frag(l), fpos_frag(r));
 104         if (v)
 105                 return v;
 106         return (int)(fpos_off(l) - fpos_off(r));
 107 }
 108
 109 /*
 110  * When possible, we try to satisfy a readdir by peeking at the
 111  * dcache.  We make this work by carefully ordering dentries on
 112  * d_child when we initially get results back from the MDS, and
 113  * falling back to a "normal" sync readdir if any dentries in the dir
 114  * are dropped.
 115  *
 116  * Complete dir indicates that we have all dentries in the dir.  It is
 117  * defined IFF we hold CEPH_CAP_FILE_SHARED (which will be revoked by
 118  * the MDS if/when the directory is modified).
 119  */
 120 static int __dcache_readdir(struct file *file,  struct dir_context *ctx,
 121                             u32 shared_gen)
 122 {
 123         struct ceph_file_info *fi = file->private_data;
 124         struct dentry *parent = file->f_path.dentry;
 125         struct inode *dir = d_inode(parent);
 126         struct list_head *p;
 127         struct dentry *dentry, *last;
 128         struct ceph_dentry_info *di;
 129         int err = 0;
 130
 131         /* claim ref on last dentry we returned */
 132         last = fi->dentry;
 133         fi->dentry = NULL;
 134
 135         dout("__dcache_readdir %p v%u at %llu (last %p)\n",
 136              dir, shared_gen, ctx->pos, last);
 137
 138         spin_lock(&parent->d_lock);
 139
 140         /* start at beginning? */
 141         if (ctx->pos == 2 || last == NULL ||
 142             fpos_cmp(ctx->pos, ceph_dentry(last)->offset) < 0) {
 143                 if (list_empty(&parent->d_subdirs))
 144                         goto out_unlock;
 145                 p = parent->d_subdirs.prev;
 146                 dout(" initial p %p/%p\n", p->prev, p->next);
 147         } else {
 148                 p = last->d_child.prev;
 149         }
 150
 151 more:
 152         dentry = list_entry(p, struct dentry, d_child);
 153         di = ceph_dentry(dentry);
 154         while (1) {
 155                 dout(" p %p/%p %s d_subdirs %p/%p\n", p->prev, p->next,
 156                      d_unhashed(dentry) ? "!hashed" : "hashed",
 157                      parent->d_subdirs.prev, parent->d_subdirs.next);
 158                 if (p == &parent->d_subdirs) {
 159                         fi->flags |= CEPH_F_ATEND;
 160                         goto out_unlock;
 161                 }
 162                 spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED);
 163                 if (di->lease_shared_gen == shared_gen &&
 164                     !d_unhashed(dentry) && d_really_is_positive(dentry) &&
 165                     ceph_snap(d_inode(dentry)) != CEPH_SNAPDIR &&
 166                     ceph_ino(d_inode(dentry)) != CEPH_INO_CEPH &&
 167                     fpos_cmp(ctx->pos, di->offset) <= 0)
 168                         break;
 169                 dout(" skipping %p %pd at %llu (%llu)%s%s\n", dentry,
 170                      dentry, di->offset,
 171                      ctx->pos, d_unhashed(dentry) ? " unhashed" : "",
 172                      !d_inode(dentry) ? " null" : "");
 173                 spin_unlock(&dentry->d_lock);
 174                 p = p->prev;
 175                 dentry = list_entry(p, struct dentry, d_child);
 176                 di = ceph_dentry(dentry);
 177         }
 178
 179         dget_dlock(dentry);
 180         spin_unlock(&dentry->d_lock);
 181         spin_unlock(&parent->d_lock);
 182
 183         /* make sure a dentry wasn't dropped while we didn't have parent lock */
 184         if (!ceph_dir_is_complete_ordered(dir)) {
 185                 dout(" lost dir complete on %p; falling back to mds\n", dir);
 186                 dput(dentry);
 187                 err = -EAGAIN;
 188                 goto out;
 189         }
 190
 191         dout(" %llu (%llu) dentry %p %pd %p\n", di->offset, ctx->pos,
 192              dentry, dentry, d_inode(dentry));
 193         if (!dir_emit(ctx, dentry->d_name.name,
 194                       dentry->d_name.len,
 195                       ceph_translate_ino(dentry->d_sb, d_inode(dentry)->i_ino),
 196                       d_inode(dentry)->i_mode >> 12)) {
 197                 if (last) {
 198                         /* remember our position */
 199                         fi->dentry = last;
 200                         fi->next_offset = fpos_off(di->offset);
 201                 }
 202                 dput(dentry);
 203                 return 0;
 204         }
 205
 206         ctx->pos = di->offset + 1;
 207
 208         if (last)
 209                 dput(last);
 210         last = dentry;
 211
 212         spin_lock(&parent->d_lock);
 213         p = p->prev;    /* advance to next dentry */
 214         goto more;
 215
 216 out_unlock:
 217         spin_unlock(&parent->d_lock);
 218 out:
 219         if (last)
 220                 dput(last);
 221         return err;
 222 }
 223
 224 /*
 225  * make note of the last dentry we read, so we can
 226  * continue at the same lexicographical point,
 227  * regardless of what dir changes take place on the
 228  * server.
 229  */
 230 static int note_last_dentry(struct ceph_file_info *fi, const char *name,
 231                             int len)
 232 {
 233         kfree(fi->last_name);
 234         fi->last_name = kmalloc(len+1, GFP_NOFS);
 235         if (!fi->last_name)
 236                 return -ENOMEM;
 237         memcpy(fi->last_name, name, len);
 238         fi->last_name[len] = 0;
 239         dout("note_last_dentry '%s'\n", fi->last_name);
 240         return 0;
 241 }
 242
 243 static int ceph_readdir(struct file *file, struct dir_context *ctx)
 244 {
 245         struct ceph_file_info *fi = file->private_data;
 246         struct inode *inode = file_inode(file);
 247         struct ceph_inode_info *ci = ceph_inode(inode);
 248         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
 249         struct ceph_mds_client *mdsc = fsc->mdsc;
 250         unsigned frag = fpos_frag(ctx->pos);
 251         int off = fpos_off(ctx->pos);
 252         int err;
 253         u32 ftype;
 254         struct ceph_mds_reply_info_parsed *rinfo;
 255
 256         dout("readdir %p file %p frag %u off %u\n", inode, file, frag, off);
 257         if (fi->flags & CEPH_F_ATEND)
 258                 return 0;
 259
 260         /* always start with . and .. */
 261         if (ctx->pos == 0) {
 262                 dout("readdir off 0 -> '.'\n");
 263                 if (!dir_emit(ctx, ".", 1,
 264                             ceph_translate_ino(inode->i_sb, inode->i_ino),
 265                             inode->i_mode >> 12))
 266                         return 0;
 267                 ctx->pos = 1;
 268                 off = 1;
 269         }
 270         if (ctx->pos == 1) {
 271                 ino_t ino = parent_ino(file->f_path.dentry);
 272                 dout("readdir off 1 -> '..'\n");
 273                 if (!dir_emit(ctx, "..", 2,
 274                             ceph_translate_ino(inode->i_sb, ino),
 275                             inode->i_mode >> 12))
 276                         return 0;
 277                 ctx->pos = 2;
 278                 off = 2;
 279         }
 280
 281         /* can we use the dcache? */
 282         spin_lock(&ci->i_ceph_lock);
 283         if ((ctx->pos == 2 || fi->dentry) &&
 284             ceph_test_mount_opt(fsc, DCACHE) &&
 285             !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
 286             ceph_snap(inode) != CEPH_SNAPDIR &&
 287             __ceph_dir_is_complete_ordered(ci) &&
 288             __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
 289                 u32 shared_gen = ci->i_shared_gen;
 290                 spin_unlock(&ci->i_ceph_lock);
 291                 err = __dcache_readdir(file, ctx, shared_gen);
 292                 if (err != -EAGAIN)
 293                         return err;
 294                 frag = fpos_frag(ctx->pos);
 295                 off = fpos_off(ctx->pos);
 296         } else {
 297                 spin_unlock(&ci->i_ceph_lock);
 298         }
 299         if (fi->dentry) {
 300                 err = note_last_dentry(fi, fi->dentry->d_name.name,
 301                                        fi->dentry->d_name.len);
 302                 if (err)
 303                         return err;
 304                 dput(fi->dentry);
 305                 fi->dentry = NULL;
 306         }
 307
 308         /* proceed with a normal readdir */
 309
 310         if (ctx->pos == 2) {
 311                 /* note dir version at start of readdir so we can tell
 312                  * if any dentries get dropped */
 313                 fi->dir_release_count = atomic_read(&ci->i_release_count);
 314                 fi->dir_ordered_count = ci->i_ordered_count;
 315         }
 316
 317 more:
 318         /* do we have the correct frag content buffered? */
 319         if (fi->frag != frag || fi->last_readdir == NULL) {
 320                 struct ceph_mds_request *req;
 321                 int op = ceph_snap(inode) == CEPH_SNAPDIR ?
 322                         CEPH_MDS_OP_LSSNAP : CEPH_MDS_OP_READDIR;
 323
 324                 /* discard old result, if any */
 325                 if (fi->last_readdir) {
 326                         ceph_mdsc_put_request(fi->last_readdir);
 327                         fi->last_readdir = NULL;
 328                 }
 329
 330                 dout("readdir fetching %llx.%llx frag %x offset '%s'\n",
 331                      ceph_vinop(inode), frag, fi->last_name);
 332                 req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 333                 if (IS_ERR(req))
 334                         return PTR_ERR(req);
 335                 err = ceph_alloc_readdir_reply_buffer(req, inode);
 336                 if (err) {
 337                         ceph_mdsc_put_request(req);
 338                         return err;
 339                 }
 340                 /* hints to request -> mds selection code */
 341                 req->r_direct_mode = USE_AUTH_MDS;
 342                 req->r_direct_hash = ceph_frag_value(frag);
 343                 req->r_direct_is_hash = true;
 344                 if (fi->last_name) {
 345                         req->r_path2 = kstrdup(fi->last_name, GFP_NOFS);
 346                         if (!req->r_path2) {
 347                                 ceph_mdsc_put_request(req);
 348                                 return -ENOMEM;
 349                         }
 350                 }
 351                 req->r_readdir_offset = fi->next_offset;
 352                 req->r_args.readdir.frag = cpu_to_le32(frag);
 353
 354                 req->r_inode = inode;
 355                 ihold(inode);
 356                 req->r_dentry = dget(file->f_path.dentry);
 357                 err = ceph_mdsc_do_request(mdsc, NULL, req);
 358                 if (err < 0) {
 359                         ceph_mdsc_put_request(req);
 360                         return err;
 361                 }
 362                 dout("readdir got and parsed readdir result=%d"
 363                      " on frag %x, end=%d, complete=%d\n", err, frag,
 364                      (int)req->r_reply_info.dir_end,
 365                      (int)req->r_reply_info.dir_complete);
 366
 367                 if (!req->r_did_prepopulate) {
 368                         dout("readdir !did_prepopulate");
 369                         /* preclude from marking dir complete */
 370                         fi->dir_release_count--;
 371                 }
 372
 373                 /* note next offset and last dentry name */
 374                 rinfo = &req->r_reply_info;
 375                 if (le32_to_cpu(rinfo->dir_dir->frag) != frag) {
 376                         frag = le32_to_cpu(rinfo->dir_dir->frag);
 377                         if (ceph_frag_is_leftmost(frag))
 378                                 fi->next_offset = 2;
 379                         else
 380                                 fi->next_offset = 0;
 381                         off = fi->next_offset;
 382                 }
 383                 fi->frag = frag;
 384                 fi->offset = fi->next_offset;
 385                 fi->last_readdir = req;
 386
 387                 if (req->r_reply_info.dir_end) {
 388                         kfree(fi->last_name);
 389                         fi->last_name = NULL;
 390                         if (ceph_frag_is_rightmost(frag))
 391                                 fi->next_offset = 2;
 392                         else
 393                                 fi->next_offset = 0;
 394                 } else {
 395                         err = note_last_dentry(fi,
 396                                        rinfo->dir_dname[rinfo->dir_nr-1],
 397                                        rinfo->dir_dname_len[rinfo->dir_nr-1]);
 398                         if (err)
 399                                 return err;
 400                         fi->next_offset += rinfo->dir_nr;
 401                 }
 402         }
 403
 404         rinfo = &fi->last_readdir->r_reply_info;
 405         dout("readdir frag %x num %d off %d chunkoff %d\n", frag,
 406              rinfo->dir_nr, off, fi->offset);
 407
 408         ctx->pos = ceph_make_fpos(frag, off);
 409         while (off >= fi->offset && off - fi->offset < rinfo->dir_nr) {
 410                 struct ceph_mds_reply_inode *in =
 411                         rinfo->dir_in[off - fi->offset].in;
 412                 struct ceph_vino vino;
 413                 ino_t ino;
 414
 415                 dout("readdir off %d (%d/%d) -> %lld '%.*s' %p\n",
 416                      off, off - fi->offset, rinfo->dir_nr, ctx->pos,
 417                      rinfo->dir_dname_len[off - fi->offset],
 418                      rinfo->dir_dname[off - fi->offset], in);
 419                 BUG_ON(!in);
 420                 ftype = le32_to_cpu(in->mode) >> 12;
 421                 vino.ino = le64_to_cpu(in->ino);
 422                 vino.snap = le64_to_cpu(in->snapid);
 423                 ino = ceph_vino_to_ino(vino);
 424                 if (!dir_emit(ctx,
 425                             rinfo->dir_dname[off - fi->offset],
 426                             rinfo->dir_dname_len[off - fi->offset],
 427                             ceph_translate_ino(inode->i_sb, ino), ftype)) {
 428                         dout("filldir stopping us...\n");
 429                         return 0;
 430                 }
 431                 off++;
 432                 ctx->pos++;
 433         }
 434
 435         if (fi->last_name) {
 436                 ceph_mdsc_put_request(fi->last_readdir);
 437                 fi->last_readdir = NULL;
 438                 goto more;
 439         }
 440
 441         /* more frags? */
 442         if (!ceph_frag_is_rightmost(frag)) {
 443                 frag = ceph_frag_next(frag);
 444                 off = 0;
 445                 ctx->pos = ceph_make_fpos(frag, off);
 446                 dout("readdir next frag is %x\n", frag);
 447                 goto more;
 448         }
 449         fi->flags |= CEPH_F_ATEND;
 450
 451         /*
 452          * if dir_release_count still matches the dir, no dentries
 453          * were released during the whole readdir, and we should have
 454          * the complete dir contents in our cache.
 455          */
 456         spin_lock(&ci->i_ceph_lock);
 457         if (atomic_read(&ci->i_release_count) == fi->dir_release_count) {
 458                 if (ci->i_ordered_count == fi->dir_ordered_count)
 459                         dout(" marking %p complete and ordered\n", inode);
 460                 else
 461                         dout(" marking %p complete\n", inode);
 462                 __ceph_dir_set_complete(ci, fi->dir_release_count,
 463                                         fi->dir_ordered_count);
 464         }
 465         spin_unlock(&ci->i_ceph_lock);
 466
 467         dout("readdir %p file %p done.\n", inode, file);
 468         return 0;
 469 }
 470
 471 static void reset_readdir(struct ceph_file_info *fi, unsigned frag)
 472 {
 473         if (fi->last_readdir) {
 474                 ceph_mdsc_put_request(fi->last_readdir);
 475                 fi->last_readdir = NULL;
 476         }
 477         kfree(fi->last_name);
 478         fi->last_name = NULL;
 479         if (ceph_frag_is_leftmost(frag))
 480                 fi->next_offset = 2;  /* compensate for . and .. */
 481         else
 482                 fi->next_offset = 0;
 483         if (fi->dentry) {
 484                 dput(fi->dentry);
 485                 fi->dentry = NULL;
 486         }
 487         fi->flags &= ~CEPH_F_ATEND;
 488 }
 489
 490 static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
 491 {
 492         struct ceph_file_info *fi = file->private_data;
 493         struct inode *inode = file->f_mapping->host;
 494         loff_t old_offset = ceph_make_fpos(fi->frag, fi->next_offset);
 495         loff_t retval;
 496
 497         mutex_lock(&inode->i_mutex);
 498         retval = -EINVAL;
 499         switch (whence) {
 500         case SEEK_END:
 501                 offset += inode->i_size + 2;   /* FIXME */
 502                 break;
 503         case SEEK_CUR:
 504                 offset += file->f_pos;
 505         case SEEK_SET:
 506                 break;
 507         default:
 508                 goto out;
 509         }
 510
 511         if (offset >= 0) {
 512                 if (offset != file->f_pos) {
 513                         file->f_pos = offset;
 514                         file->f_version = 0;
 515                         fi->flags &= ~CEPH_F_ATEND;
 516                 }
 517                 retval = offset;
 518
 519                 /*
 520                  * discard buffered readdir content on seekdir(0), or
 521                  * seek to new frag, or seek prior to current chunk.
 522                  */
 523                 if (offset == 0 ||
 524                     fpos_frag(offset) != fi->frag ||
 525                     fpos_off(offset) < fi->offset) {
 526                         dout("dir_llseek dropping %p content\n", file);
 527                         reset_readdir(fi, fpos_frag(offset));
 528                 }
 529
 530                 /* bump dir_release_count if we did a forward seek */
 531                 if (fpos_cmp(offset, old_offset) > 0)
 532                         fi->dir_release_count--;
 533         }
 534 out:
 535         mutex_unlock(&inode->i_mutex);
 536         return retval;
 537 }
 538
 539 /*
 540  * Handle lookups for the hidden .snap directory.
 541  */
 542 int ceph_handle_snapdir(struct ceph_mds_request *req,
 543                         struct dentry *dentry, int err)
 544 {
 545         struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 546         struct inode *parent = d_inode(dentry->d_parent); /* we hold i_mutex */
 547
 548         /* .snap dir? */
 549         if (err == -ENOENT &&
 550             ceph_snap(parent) == CEPH_NOSNAP &&
 551             strcmp(dentry->d_name.name,
 552                    fsc->mount_options->snapdir_name) == 0) {
 553                 struct inode *inode = ceph_get_snapdir(parent);
 554                 dout("ENOENT on snapdir %p '%pd', linking to snapdir %p\n",
 555                      dentry, dentry, inode);
 556                 BUG_ON(!d_unhashed(dentry));
 557                 d_add(dentry, inode);
 558                 err = 0;
 559         }
 560         return err;
 561 }
 562
 563 /*
 564  * Figure out final result of a lookup/open request.
 565  *
 566  * Mainly, make sure we return the final req->r_dentry (if it already
 567  * existed) in place of the original VFS-provided dentry when they
 568  * differ.
 569  *
 570  * Gracefully handle the case where the MDS replies with -ENOENT and
 571  * no trace (which it may do, at its discretion, e.g., if it doesn't
 572  * care to issue a lease on the negative dentry).
 573  */
 574 struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 575                                   struct dentry *dentry, int err)
 576 {
 577         if (err == -ENOENT) {
 578                 /* no trace? */
 579                 err = 0;
 580                 if (!req->r_reply_info.head->is_dentry) {
 581                         dout("ENOENT and no trace, dentry %p inode %p\n",
 582                              dentry, d_inode(dentry));
 583                         if (d_really_is_positive(dentry)) {
 584                                 d_drop(dentry);
 585                                 err = -ENOENT;
 586                         } else {
 587                                 d_add(dentry, NULL);
 588                         }
 589                 }
 590         }
 591         if (err)
 592                 dentry = ERR_PTR(err);
 593         else if (dentry != req->r_dentry)
 594                 dentry = dget(req->r_dentry);   /* we got spliced */
 595         else
 596                 dentry = NULL;
 597         return dentry;
 598 }
 599
 600 static int is_root_ceph_dentry(struct inode *inode, struct dentry *dentry)
 601 {
 602         return ceph_ino(inode) == CEPH_INO_ROOT &&
 603                 strncmp(dentry->d_name.name, ".ceph", 5) == 0;
 604 }
 605
 606 /*
 607  * Look up a single dir entry.  If there is a lookup intent, inform
 608  * the MDS so that it gets our 'caps wanted' value in a single op.
 609  */
 610 static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 611                                   unsigned int flags)
 612 {
 613         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 614         struct ceph_mds_client *mdsc = fsc->mdsc;
 615         struct ceph_mds_request *req;
 616         int op;
 617         int err;
 618
 619         dout("lookup %p dentry %p '%pd'\n",
 620              dir, dentry, dentry);
 621
 622         if (dentry->d_name.len > NAME_MAX)
 623                 return ERR_PTR(-ENAMETOOLONG);
 624
 625         err = ceph_init_dentry(dentry);
 626         if (err < 0)
 627                 return ERR_PTR(err);
 628
 629         /* can we conclude ENOENT locally? */
 630         if (d_really_is_negative(dentry)) {
 631                 struct ceph_inode_info *ci = ceph_inode(dir);
 632                 struct ceph_dentry_info *di = ceph_dentry(dentry);
 633
 634                 spin_lock(&ci->i_ceph_lock);
 635                 dout(" dir %p flags are %d\n", dir, ci->i_ceph_flags);
 636                 if (strncmp(dentry->d_name.name,
 637                             fsc->mount_options->snapdir_name,
 638                             dentry->d_name.len) &&
 639                     !is_root_ceph_dentry(dir, dentry) &&
 640                     ceph_test_mount_opt(fsc, DCACHE) &&
 641                     __ceph_dir_is_complete(ci) &&
 642                     (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
 643                         spin_unlock(&ci->i_ceph_lock);
 644                         dout(" dir %p complete, -ENOENT\n", dir);
 645                         d_add(dentry, NULL);
 646                         di->lease_shared_gen = ci->i_shared_gen;
 647                         return NULL;
 648                 }
 649                 spin_unlock(&ci->i_ceph_lock);
 650         }
 651
 652         op = ceph_snap(dir) == CEPH_SNAPDIR ?
 653                 CEPH_MDS_OP_LOOKUPSNAP : CEPH_MDS_OP_LOOKUP;
 654         req = ceph_mdsc_create_request(mdsc, op, USE_ANY_MDS);
 655         if (IS_ERR(req))
 656                 return ERR_CAST(req);
 657         req->r_dentry = dget(dentry);
 658         req->r_num_caps = 2;
 659         /* we only need inode linkage */
 660         req->r_args.getattr.mask = cpu_to_le32(CEPH_STAT_CAP_INODE);
 661         req->r_locked_dir = dir;
 662         err = ceph_mdsc_do_request(mdsc, NULL, req);
 663         err = ceph_handle_snapdir(req, dentry, err);
 664         dentry = ceph_finish_lookup(req, dentry, err);
 665         ceph_mdsc_put_request(req);  /* will dput(dentry) */
 666         dout("lookup result=%p\n", dentry);
 667         return dentry;
 668 }
 669
 670 /*
 671  * If we do a create but get no trace back from the MDS, follow up with
 672  * a lookup (the VFS expects us to link up the provided dentry).
 673  */
 674 int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry)
 675 {
 676         struct dentry *result = ceph_lookup(dir, dentry, 0);
 677
 678         if (result && !IS_ERR(result)) {
 679                 /*
 680                  * We created the item, then did a lookup, and found
 681                  * it was already linked to another inode we already
 682                  * had in our cache (and thus got spliced). To not
 683                  * confuse VFS (especially when inode is a directory),
 684                  * we don't link our dentry to that inode, return an
 685                  * error instead.
 686                  *
 687                  * This event should be rare and it happens only when
 688                  * we talk to old MDS. Recent MDS does not send traceless
 689                  * reply for request that creates new inode.
 690                  */
 691                 d_drop(result);
 692                 return -ESTALE;
 693         }
 694         return PTR_ERR(result);
 695 }
 696
 697 static int ceph_mknod(struct inode *dir, struct dentry *dentry,
 698                       umode_t mode, dev_t rdev)
 699 {
 700         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 701         struct ceph_mds_client *mdsc = fsc->mdsc;
 702         struct ceph_mds_request *req;
 703         struct ceph_acls_info acls = {};
 704         int err;
 705
 706         if (ceph_snap(dir) != CEPH_NOSNAP)
 707                 return -EROFS;
 708
 709         err = ceph_pre_init_acls(dir, &mode, &acls);
 710         if (err < 0)
 711                 return err;
 712
 713         dout("mknod in dir %p dentry %p mode 0%ho rdev %d\n",
 714              dir, dentry, mode, rdev);
 715         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_MKNOD, USE_AUTH_MDS);
 716         if (IS_ERR(req)) {
 717                 err = PTR_ERR(req);
 718                 goto out;
 719         }
 720         req->r_dentry = dget(dentry);
 721         req->r_num_caps = 2;
 722         req->r_locked_dir = dir;
 723         req->r_args.mknod.mode = cpu_to_le32(mode);
 724         req->r_args.mknod.rdev = cpu_to_le32(rdev);
 725         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 726         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 727         if (acls.pagelist) {
 728                 req->r_pagelist = acls.pagelist;
 729                 acls.pagelist = NULL;
 730         }
 731         err = ceph_mdsc_do_request(mdsc, dir, req);
 732         if (!err && !req->r_reply_info.head->is_dentry)
 733                 err = ceph_handle_notrace_create(dir, dentry);
 734         ceph_mdsc_put_request(req);
 735 out:
 736         if (!err)
 737                 ceph_init_inode_acls(d_inode(dentry), &acls);
 738         else
 739                 d_drop(dentry);
 740         ceph_release_acls_info(&acls);
 741         return err;
 742 }
 743
 744 static int ceph_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 745                        bool excl)
 746 {
 747         return ceph_mknod(dir, dentry, mode, 0);
 748 }
 749
 750 static int ceph_symlink(struct inode *dir, struct dentry *dentry,
 751                             const char *dest)
 752 {
 753         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 754         struct ceph_mds_client *mdsc = fsc->mdsc;
 755         struct ceph_mds_request *req;
 756         int err;
 757
 758         if (ceph_snap(dir) != CEPH_NOSNAP)
 759                 return -EROFS;
 760
 761         dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
 762         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
 763         if (IS_ERR(req)) {
 764                 err = PTR_ERR(req);
 765                 goto out;
 766         }
 767         req->r_path2 = kstrdup(dest, GFP_NOFS);
 768         if (!req->r_path2) {
 769                 err = -ENOMEM;
 770                 ceph_mdsc_put_request(req);
 771                 goto out;
 772         }
 773         req->r_locked_dir = dir;
 774         req->r_dentry = dget(dentry);
 775         req->r_num_caps = 2;
 776         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 777         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 778         err = ceph_mdsc_do_request(mdsc, dir, req);
 779         if (!err && !req->r_reply_info.head->is_dentry)
 780                 err = ceph_handle_notrace_create(dir, dentry);
 781         ceph_mdsc_put_request(req);
 782 out:
 783         if (err)
 784                 d_drop(dentry);
 785         return err;
 786 }
 787
 788 static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 789 {
 790         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 791         struct ceph_mds_client *mdsc = fsc->mdsc;
 792         struct ceph_mds_request *req;
 793         struct ceph_acls_info acls = {};
 794         int err = -EROFS;
 795         int op;
 796
 797         if (ceph_snap(dir) == CEPH_SNAPDIR) {
 798                 /* mkdir .snap/foo is a MKSNAP */
 799                 op = CEPH_MDS_OP_MKSNAP;
 800                 dout("mksnap dir %p snap '%pd' dn %p\n", dir,
 801                      dentry, dentry);
 802         } else if (ceph_snap(dir) == CEPH_NOSNAP) {
 803                 dout("mkdir dir %p dn %p mode 0%ho\n", dir, dentry, mode);
 804                 op = CEPH_MDS_OP_MKDIR;
 805         } else {
 806                 goto out;
 807         }
 808
 809         mode |= S_IFDIR;
 810         err = ceph_pre_init_acls(dir, &mode, &acls);
 811         if (err < 0)
 812                 goto out;
 813
 814         req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 815         if (IS_ERR(req)) {
 816                 err = PTR_ERR(req);
 817                 goto out;
 818         }
 819
 820         req->r_dentry = dget(dentry);
 821         req->r_num_caps = 2;
 822         req->r_locked_dir = dir;
 823         req->r_args.mkdir.mode = cpu_to_le32(mode);
 824         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 825         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 826         if (acls.pagelist) {
 827                 req->r_pagelist = acls.pagelist;
 828                 acls.pagelist = NULL;
 829         }
 830         err = ceph_mdsc_do_request(mdsc, dir, req);
 831         if (!err &&
 832             !req->r_reply_info.head->is_target &&
 833             !req->r_reply_info.head->is_dentry)
 834                 err = ceph_handle_notrace_create(dir, dentry);
 835         ceph_mdsc_put_request(req);
 836 out:
 837         if (!err)
 838                 ceph_init_inode_acls(d_inode(dentry), &acls);
 839         else
 840                 d_drop(dentry);
 841         ceph_release_acls_info(&acls);
 842         return err;
 843 }
 844
 845 static int ceph_link(struct dentry *old_dentry, struct inode *dir,
 846                      struct dentry *dentry)
 847 {
 848         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 849         struct ceph_mds_client *mdsc = fsc->mdsc;
 850         struct ceph_mds_request *req;
 851         int err;
 852
 853         if (ceph_snap(dir) != CEPH_NOSNAP)
 854                 return -EROFS;
 855
 856         dout("link in dir %p old_dentry %p dentry %p\n", dir,
 857              old_dentry, dentry);
 858         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_LINK, USE_AUTH_MDS);
 859         if (IS_ERR(req)) {
 860                 d_drop(dentry);
 861                 return PTR_ERR(req);
 862         }
 863         req->r_dentry = dget(dentry);
 864         req->r_num_caps = 2;
 865         req->r_old_dentry = dget(old_dentry);
 866         req->r_locked_dir = dir;
 867         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 868         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 869         /* release LINK_SHARED on source inode (mds will lock it) */
 870         req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
 871         err = ceph_mdsc_do_request(mdsc, dir, req);
 872         if (err) {
 873                 d_drop(dentry);
 874         } else if (!req->r_reply_info.head->is_dentry) {
 875                 ihold(d_inode(old_dentry));
 876                 d_instantiate(dentry, d_inode(old_dentry));
 877         }
 878         ceph_mdsc_put_request(req);
 879         return err;
 880 }
 881
 882 /*
 883  * For a soon-to-be unlinked file, drop the AUTH_RDCACHE caps.  If it
 884  * looks like the link count will hit 0, drop any other caps (other
 885  * than PIN) we don't specifically want (due to the file still being
 886  * open).
 887  */
 888 static int drop_caps_for_unlink(struct inode *inode)
 889 {
 890         struct ceph_inode_info *ci = ceph_inode(inode);
 891         int drop = CEPH_CAP_LINK_SHARED | CEPH_CAP_LINK_EXCL;
 892
 893         spin_lock(&ci->i_ceph_lock);
 894         if (inode->i_nlink == 1) {
 895                 drop |= ~(__ceph_caps_wanted(ci) | CEPH_CAP_PIN);
 896                 ci->i_ceph_flags |= CEPH_I_NODELAY;
 897         }
 898         spin_unlock(&ci->i_ceph_lock);
 899         return drop;
 900 }
 901
 902 /*
 903  * rmdir and unlink are differ only by the metadata op code
 904  */
 905 static int ceph_unlink(struct inode *dir, struct dentry *dentry)
 906 {
 907         struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 908         struct ceph_mds_client *mdsc = fsc->mdsc;
 909         struct inode *inode = d_inode(dentry);
 910         struct ceph_mds_request *req;
 911         int err = -EROFS;
 912         int op;
 913
 914         if (ceph_snap(dir) == CEPH_SNAPDIR) {
 915                 /* rmdir .snap/foo is RMSNAP */
 916                 dout("rmsnap dir %p '%pd' dn %p\n", dir, dentry, dentry);
 917                 op = CEPH_MDS_OP_RMSNAP;
 918         } else if (ceph_snap(dir) == CEPH_NOSNAP) {
 919                 dout("unlink/rmdir dir %p dn %p inode %p\n",
 920                      dir, dentry, inode);
 921                 op = d_is_dir(dentry) ?
 922                         CEPH_MDS_OP_RMDIR : CEPH_MDS_OP_UNLINK;
 923         } else
 924                 goto out;
 925         req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 926         if (IS_ERR(req)) {
 927                 err = PTR_ERR(req);
 928                 goto out;
 929         }
 930         req->r_dentry = dget(dentry);
 931         req->r_num_caps = 2;
 932         req->r_locked_dir = dir;
 933         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 934         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 935         req->r_inode_drop = drop_caps_for_unlink(inode);
 936         err = ceph_mdsc_do_request(mdsc, dir, req);
 937         if (!err && !req->r_reply_info.head->is_dentry)
 938                 d_delete(dentry);
 939         ceph_mdsc_put_request(req);
 940 out:
 941         return err;
 942 }
 943
 944 static int ceph_rename(struct inode *old_dir, struct dentry *old_dentry,
 945                        struct inode *new_dir, struct dentry *new_dentry)
 946 {
 947         struct ceph_fs_client *fsc = ceph_sb_to_client(old_dir->i_sb);
 948         struct ceph_mds_client *mdsc = fsc->mdsc;
 949         struct ceph_mds_request *req;
 950         int op = CEPH_MDS_OP_RENAME;
 951         int err;
 952
 953         if (ceph_snap(old_dir) != ceph_snap(new_dir))
 954                 return -EXDEV;
 955         if (ceph_snap(old_dir) != CEPH_NOSNAP) {
 956                 if (old_dir == new_dir && ceph_snap(old_dir) == CEPH_SNAPDIR)
 957                         op = CEPH_MDS_OP_RENAMESNAP;
 958                 else
 959                         return -EROFS;
 960         }
 961         dout("rename dir %p dentry %p to dir %p dentry %p\n",
 962              old_dir, old_dentry, new_dir, new_dentry);
 963         req = ceph_mdsc_create_request(mdsc, op, USE_AUTH_MDS);
 964         if (IS_ERR(req))
 965                 return PTR_ERR(req);
 966         ihold(old_dir);
 967         req->r_dentry = dget(new_dentry);
 968         req->r_num_caps = 2;
 969         req->r_old_dentry = dget(old_dentry);
 970         req->r_old_dentry_dir = old_dir;
 971         req->r_locked_dir = new_dir;
 972         req->r_old_dentry_drop = CEPH_CAP_FILE_SHARED;
 973         req->r_old_dentry_unless = CEPH_CAP_FILE_EXCL;
 974         req->r_dentry_drop = CEPH_CAP_FILE_SHARED;
 975         req->r_dentry_unless = CEPH_CAP_FILE_EXCL;
 976         /* release LINK_RDCACHE on source inode (mds will lock it) */
 977         req->r_old_inode_drop = CEPH_CAP_LINK_SHARED;
 978         if (d_really_is_positive(new_dentry))
 979                 req->r_inode_drop = drop_caps_for_unlink(d_inode(new_dentry));
 980         err = ceph_mdsc_do_request(mdsc, old_dir, req);
 981         if (!err && !req->r_reply_info.head->is_dentry) {
 982                 /*
 983                  * Normally d_move() is done by fill_trace (called by
 984                  * do_request, above).  If there is no trace, we need
 985                  * to do it here.
 986                  */
 987
 988                 d_move(old_dentry, new_dentry);
 989
 990                 /* ensure target dentry is invalidated, despite
 991                    rehashing bug in vfs_rename_dir */
 992                 ceph_invalidate_dentry_lease(new_dentry);
 993
 994                 /* d_move screws up sibling dentries' offsets */
 995                 ceph_dir_clear_complete(old_dir);
 996                 ceph_dir_clear_complete(new_dir);
 997
 998         }
 999         ceph_mdsc_put_request(req);
1000         return err;
1001 }
1002
1003 /*
1004  * Ensure a dentry lease will no longer revalidate.
1005  */
1006 void ceph_invalidate_dentry_lease(struct dentry *dentry)
1007 {
1008         spin_lock(&dentry->d_lock);
1009         dentry->d_time = jiffies;
1010         ceph_dentry(dentry)->lease_shared_gen = 0;
1011         spin_unlock(&dentry->d_lock);
1012 }
1013
1014 /*
1015  * Check if dentry lease is valid.  If not, delete the lease.  Try to
1016  * renew if the least is more than half up.
1017  */
1018 static int dentry_lease_is_valid(struct dentry *dentry)
1019 {
1020         struct ceph_dentry_info *di;
1021         struct ceph_mds_session *s;
1022         int valid = 0;
1023         u32 gen;
1024         unsigned long ttl;
1025         struct ceph_mds_session *session = NULL;
1026         struct inode *dir = NULL;
1027         u32 seq = 0;
1028
1029         spin_lock(&dentry->d_lock);
1030         di = ceph_dentry(dentry);
1031         if (di->lease_session) {
1032                 s = di->lease_session;
1033                 spin_lock(&s->s_gen_ttl_lock);
1034                 gen = s->s_cap_gen;
1035                 ttl = s->s_cap_ttl;
1036                 spin_unlock(&s->s_gen_ttl_lock);
1037
1038                 if (di->lease_gen == gen &&
1039                     time_before(jiffies, dentry->d_time) &&
1040                     time_before(jiffies, ttl)) {
1041                         valid = 1;
1042                         if (di->lease_renew_after &&
1043                             time_after(jiffies, di->lease_renew_after)) {
1044                                 /* we should renew */
1045                                 dir = d_inode(dentry->d_parent);
1046                                 session = ceph_get_mds_session(s);
1047                                 seq = di->lease_seq;
1048                                 di->lease_renew_after = 0;
1049                                 di->lease_renew_from = jiffies;
1050                         }
1051                 }
1052         }
1053         spin_unlock(&dentry->d_lock);
1054
1055         if (session) {
1056                 ceph_mdsc_lease_send_msg(session, dir, dentry,
1057                                          CEPH_MDS_LEASE_RENEW, seq);
1058                 ceph_put_mds_session(session);
1059         }
1060         dout("dentry_lease_is_valid - dentry %p = %d\n", dentry, valid);
1061         return valid;
1062 }
1063
1064 /*
1065  * Check if directory-wide content lease/cap is valid.
1066  */
1067 static int dir_lease_is_valid(struct inode *dir, struct dentry *dentry)
1068 {
1069         struct ceph_inode_info *ci = ceph_inode(dir);
1070         struct ceph_dentry_info *di = ceph_dentry(dentry);
1071         int valid = 0;
1072
1073         spin_lock(&ci->i_ceph_lock);
1074         if (ci->i_shared_gen == di->lease_shared_gen)
1075                 valid = __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1);
1076         spin_unlock(&ci->i_ceph_lock);
1077         dout("dir_lease_is_valid dir %p v%u dentry %p v%u = %d\n",
1078              dir, (unsigned)ci->i_shared_gen, dentry,
1079              (unsigned)di->lease_shared_gen, valid);
1080         return valid;
1081 }
1082
1083 /*
1084  * Check if cached dentry can be trusted.
1085  */
1086 static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags)
1087 {
1088         int valid = 0;
1089         struct inode *dir;
1090
1091         if (flags & LOOKUP_RCU)
1092                 return -ECHILD;
1093
1094         dout("d_revalidate %p '%pd' inode %p offset %lld\n", dentry,
1095              dentry, d_inode(dentry), ceph_dentry(dentry)->offset);
1096
1097         dir = ceph_get_dentry_parent_inode(dentry);
1098
1099         /* always trust cached snapped dentries, snapdir dentry */
1100         if (ceph_snap(dir) != CEPH_NOSNAP) {
1101                 dout("d_revalidate %p '%pd' inode %p is SNAPPED\n", dentry,
1102                      dentry, d_inode(dentry));
1103                 valid = 1;
1104         } else if (d_really_is_positive(dentry) &&
1105                    ceph_snap(d_inode(dentry)) == CEPH_SNAPDIR) {
1106                 valid = 1;
1107         } else if (dentry_lease_is_valid(dentry) ||
1108                    dir_lease_is_valid(dir, dentry)) {
1109                 if (d_really_is_positive(dentry))
1110                         valid = ceph_is_any_caps(d_inode(dentry));
1111                 else
1112                         valid = 1;
1113         }
1114
1115         dout("d_revalidate %p %s\n", dentry, valid ? "valid" : "invalid");
1116         if (valid) {
1117                 ceph_dentry_lru_touch(dentry);
1118         } else {
1119                 ceph_dir_clear_complete(dir);
1120         }
1121         iput(dir);
1122         return valid;
1123 }
1124
1125 /*
1126  * Release our ceph_dentry_info.
1127  */
1128 static void ceph_d_release(struct dentry *dentry)
1129 {
1130         struct ceph_dentry_info *di = ceph_dentry(dentry);
1131
1132         dout("d_release %p\n", dentry);
1133         ceph_dentry_lru_del(dentry);
1134         if (di->lease_session)
1135                 ceph_put_mds_session(di->lease_session);
1136         kmem_cache_free(ceph_dentry_cachep, di);
1137         dentry->d_fsdata = NULL;
1138 }
1139
1140 static int ceph_snapdir_d_revalidate(struct dentry *dentry,
1141                                           unsigned int flags)
1142 {
1143         /*
1144          * Eventually, we'll want to revalidate snapped metadata
1145          * too... probably...
1146          */
1147         return 1;
1148 }
1149
1150 /*
1151  * When the VFS prunes a dentry from the cache, we need to clear the
1152  * complete flag on the parent directory.
1153  *
1154  * Called under dentry->d_lock.
1155  */
1156 static void ceph_d_prune(struct dentry *dentry)
1157 {
1158         dout("ceph_d_prune %p\n", dentry);
1159
1160         /* do we have a valid parent? */
1161         if (IS_ROOT(dentry))
1162                 return;
1163
1164         /* if we are not hashed, we don't affect dir's completeness */
1165         if (d_unhashed(dentry))
1166                 return;
1167
1168         /*
1169          * we hold d_lock, so d_parent is stable, and d_fsdata is never
1170          * cleared until d_release
1171          */
1172         ceph_dir_clear_complete(d_inode(dentry->d_parent));
1173 }
1174
1175 /*
1176  * read() on a dir.  This weird interface hack only works if mounted
1177  * with '-o dirstat'.
1178  */
1179 static ssize_t ceph_read_dir(struct file *file, char __user *buf, size_t size,
1180                              loff_t *ppos)
1181 {
1182         struct ceph_file_info *cf = file->private_data;
1183         struct inode *inode = file_inode(file);
1184         struct ceph_inode_info *ci = ceph_inode(inode);
1185         int left;
1186         const int bufsize = 1024;
1187
1188         if (!ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb), DIRSTAT))
1189                 return -EISDIR;
1190
1191         if (!cf->dir_info) {
1192                 cf->dir_info = kmalloc(bufsize, GFP_NOFS);
1193                 if (!cf->dir_info)
1194                         return -ENOMEM;
1195                 cf->dir_info_len =
1196                         snprintf(cf->dir_info, bufsize,
1197                                 "entries:   %20lld\n"
1198                                 " files:    %20lld\n"
1199                                 " subdirs:  %20lld\n"
1200                                 "rentries:  %20lld\n"
1201                                 " rfiles:   %20lld\n"
1202                                 " rsubdirs: %20lld\n"
1203                                 "rbytes:    %20lld\n"
1204                                 "rctime:    %10ld.%09ld\n",
1205                                 ci->i_files + ci->i_subdirs,
1206                                 ci->i_files,
1207                                 ci->i_subdirs,
1208                                 ci->i_rfiles + ci->i_rsubdirs,
1209                                 ci->i_rfiles,
1210                                 ci->i_rsubdirs,
1211                                 ci->i_rbytes,
1212                                 (long)ci->i_rctime.tv_sec,
1213                                 (long)ci->i_rctime.tv_nsec);
1214         }
1215
1216         if (*ppos >= cf->dir_info_len)
1217                 return 0;
1218         size = min_t(unsigned, size, cf->dir_info_len-*ppos);
1219         left = copy_to_user(buf, cf->dir_info + *ppos, size);
1220         if (left == size)
1221                 return -EFAULT;
1222         *ppos += (size - left);
1223         return size - left;
1224 }
1225
1226 /*
1227  * an fsync() on a dir will wait for any uncommitted directory
1228  * operations to commit.
1229  */
1230 static int ceph_dir_fsync(struct file *file, loff_t start, loff_t end,
1231                           int datasync)
1232 {
1233         struct inode *inode = file_inode(file);
1234         struct ceph_inode_info *ci = ceph_inode(inode);
1235         struct list_head *head = &ci->i_unsafe_dirops;
1236         struct ceph_mds_request *req;
1237         u64 last_tid;
1238         int ret = 0;
1239
1240         dout("dir_fsync %p\n", inode);
1241         ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
1242         if (ret)
1243                 return ret;
1244         mutex_lock(&inode->i_mutex);
1245
1246         spin_lock(&ci->i_unsafe_lock);
1247         if (list_empty(head))
1248                 goto out;
1249
1250         req = list_entry(head->prev,
1251                          struct ceph_mds_request, r_unsafe_dir_item);
1252         last_tid = req->r_tid;
1253
1254         do {
1255                 ceph_mdsc_get_request(req);
1256                 spin_unlock(&ci->i_unsafe_lock);
1257
1258                 dout("dir_fsync %p wait on tid %llu (until %llu)\n",
1259                      inode, req->r_tid, last_tid);
1260                 if (req->r_timeout) {
1261                         unsigned long time_left = wait_for_completion_timeout(
1262                                                         &req->r_safe_completion,
1263                                                         req->r_timeout);
1264                         if (time_left > 0)
1265                                 ret = 0;
1266                         else
1267                                 ret = -EIO;  /* timed out */
1268                 } else {
1269                         wait_for_completion(&req->r_safe_completion);
1270                 }
1271                 ceph_mdsc_put_request(req);
1272
1273                 spin_lock(&ci->i_unsafe_lock);
1274                 if (ret || list_empty(head))
1275                         break;
1276                 req = list_entry(head->next,
1277                                  struct ceph_mds_request, r_unsafe_dir_item);
1278         } while (req->r_tid < last_tid);
1279 out:
1280         spin_unlock(&ci->i_unsafe_lock);
1281         mutex_unlock(&inode->i_mutex);
1282
1283         return ret;
1284 }
1285
1286 /*
1287  * We maintain a private dentry LRU.
1288  *
1289  * FIXME: this needs to be changed to a per-mds lru to be useful.
1290  */
1291 void ceph_dentry_lru_add(struct dentry *dn)
1292 {
1293         struct ceph_dentry_info *di = ceph_dentry(dn);
1294         struct ceph_mds_client *mdsc;
1295
1296         dout("dentry_lru_add %p %p '%pd'\n", di, dn, dn);
1297         mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1298         spin_lock(&mdsc->dentry_lru_lock);
1299         list_add_tail(&di->lru, &mdsc->dentry_lru);
1300         mdsc->num_dentry++;
1301         spin_unlock(&mdsc->dentry_lru_lock);
1302 }
1303
1304 void ceph_dentry_lru_touch(struct dentry *dn)
1305 {
1306         struct ceph_dentry_info *di = ceph_dentry(dn);
1307         struct ceph_mds_client *mdsc;
1308
1309         dout("dentry_lru_touch %p %p '%pd' (offset %lld)\n", di, dn, dn,
1310              di->offset);
1311         mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1312         spin_lock(&mdsc->dentry_lru_lock);
1313         list_move_tail(&di->lru, &mdsc->dentry_lru);
1314         spin_unlock(&mdsc->dentry_lru_lock);
1315 }
1316
1317 void ceph_dentry_lru_del(struct dentry *dn)
1318 {
1319         struct ceph_dentry_info *di = ceph_dentry(dn);
1320         struct ceph_mds_client *mdsc;
1321
1322         dout("dentry_lru_del %p %p '%pd'\n", di, dn, dn);
1323         mdsc = ceph_sb_to_client(dn->d_sb)->mdsc;
1324         spin_lock(&mdsc->dentry_lru_lock);
1325         list_del_init(&di->lru);
1326         mdsc->num_dentry--;
1327         spin_unlock(&mdsc->dentry_lru_lock);
1328 }
1329
1330 /*
1331  * Return name hash for a given dentry.  This is dependent on
1332  * the parent directory's hash function.
1333  */
1334 unsigned ceph_dentry_hash(struct inode *dir, struct dentry *dn)
1335 {
1336         struct ceph_inode_info *dci = ceph_inode(dir);
1337
1338         switch (dci->i_dir_layout.dl_dir_hash) {
1339         case 0: /* for backward compat */
1340         case CEPH_STR_HASH_LINUX:
1341                 return dn->d_name.hash;
1342
1343         default:
1344                 return ceph_str_hash(dci->i_dir_layout.dl_dir_hash,
1345                                      dn->d_name.name, dn->d_name.len);
1346         }
1347 }
1348
1349 const struct file_operations ceph_dir_fops = {
1350         .read = ceph_read_dir,
1351         .iterate = ceph_readdir,
1352         .llseek = ceph_dir_llseek,
1353         .open = ceph_open,
1354         .release = ceph_release,
1355         .unlocked_ioctl = ceph_ioctl,
1356         .fsync = ceph_dir_fsync,
1357 };
1358
1359 const struct file_operations ceph_snapdir_fops = {
1360         .iterate = ceph_readdir,
1361         .llseek = ceph_dir_llseek,
1362         .open = ceph_open,
1363         .release = ceph_release,
1364 };
1365
1366 const struct inode_operations ceph_dir_iops = {
1367         .lookup = ceph_lookup,
1368         .permission = ceph_permission,
1369         .getattr = ceph_getattr,
1370         .setattr = ceph_setattr,
1371         .setxattr = ceph_setxattr,
1372         .getxattr = ceph_getxattr,
1373         .listxattr = ceph_listxattr,
1374         .removexattr = ceph_removexattr,
1375         .get_acl = ceph_get_acl,
1376         .set_acl = ceph_set_acl,
1377         .mknod = ceph_mknod,
1378         .symlink = ceph_symlink,
1379         .mkdir = ceph_mkdir,
1380         .link = ceph_link,
1381         .unlink = ceph_unlink,
1382         .rmdir = ceph_unlink,
1383         .rename = ceph_rename,
1384         .create = ceph_create,
1385         .atomic_open = ceph_atomic_open,
1386 };
1387
1388 const struct inode_operations ceph_snapdir_iops = {
1389         .lookup = ceph_lookup,
1390         .permission = ceph_permission,
1391         .getattr = ceph_getattr,
1392         .mkdir = ceph_mkdir,
1393         .rmdir = ceph_unlink,
1394         .rename = ceph_rename,
1395 };
1396
1397 const struct dentry_operations ceph_dentry_ops = {
1398         .d_revalidate = ceph_d_revalidate,
1399         .d_release = ceph_d_release,
1400         .d_prune = ceph_d_prune,
1401 };
1402
1403 const struct dentry_operations ceph_snapdir_dentry_ops = {
1404         .d_revalidate = ceph_snapdir_d_revalidate,
1405         .d_release = ceph_d_release,
1406 };
1407
1408 const struct dentry_operations ceph_snap_dentry_ops = {
1409         .d_release = ceph_d_release,
1410         .d_prune = ceph_d_prune,
1411 };