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