fs/ceph/inode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/ceph/ceph_debug.h>
   3
   4 #include <linux/module.h>
   5 #include <linux/fs.h>
   6 #include <linux/slab.h>
   7 #include <linux/string.h>
   8 #include <linux/uaccess.h>
   9 #include <linux/kernel.h>
  10 #include <linux/writeback.h>
  11 #include <linux/vmalloc.h>
  12 #include <linux/xattr.h>
  13 #include <linux/posix_acl.h>
  14 #include <linux/random.h>
  15 #include <linux/sort.h>
  16 #include <linux/iversion.h>
  17
  18 #include "super.h"
  19 #include "mds_client.h"
  20 #include "cache.h"
  21 #include <linux/ceph/decode.h>
  22
  23 /*
  24  * Ceph inode operations
  25  *
  26  * Implement basic inode helpers (get, alloc) and inode ops (getattr,
  27  * setattr, etc.), xattr helpers, and helpers for assimilating
  28  * metadata returned by the MDS into our cache.
  29  *
  30  * Also define helpers for doing asynchronous writeback, invalidation,
  31  * and truncation for the benefit of those who can't afford to block
  32  * (typically because they are in the message handler path).
  33  */
  34
  35 static const struct inode_operations ceph_symlink_iops;
  36
  37 static void ceph_inode_work(struct work_struct *work);
  38
  39 /*
  40  * find or create an inode, given the ceph ino number
  41  */
  42 static int ceph_set_ino_cb(struct inode *inode, void *data)
  43 {
  44         ceph_inode(inode)->i_vino = *(struct ceph_vino *)data;
  45         inode->i_ino = ceph_vino_to_ino(*(struct ceph_vino *)data);
  46         inode_set_iversion_raw(inode, 0);
  47         return 0;
  48 }
  49
  50 struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino)
  51 {
  52         struct inode *inode;
  53         ino_t t = ceph_vino_to_ino(vino);
  54
  55         inode = iget5_locked(sb, t, ceph_ino_compare, ceph_set_ino_cb, &vino);
  56         if (!inode)
  57                 return ERR_PTR(-ENOMEM);
  58         if (inode->i_state & I_NEW) {
  59                 dout("get_inode created new inode %p %llx.%llx ino %llx\n",
  60                      inode, ceph_vinop(inode), (u64)inode->i_ino);
  61                 unlock_new_inode(inode);
  62         }
  63
  64         dout("get_inode on %lu=%llx.%llx got %p\n", inode->i_ino, vino.ino,
  65              vino.snap, inode);
  66         return inode;
  67 }
  68
  69 /*
  70  * get/constuct snapdir inode for a given directory
  71  */
  72 struct inode *ceph_get_snapdir(struct inode *parent)
  73 {
  74         struct ceph_vino vino = {
  75                 .ino = ceph_ino(parent),
  76                 .snap = CEPH_SNAPDIR,
  77         };
  78         struct inode *inode = ceph_get_inode(parent->i_sb, vino);
  79         struct ceph_inode_info *ci = ceph_inode(inode);
  80
  81         BUG_ON(!S_ISDIR(parent->i_mode));
  82         if (IS_ERR(inode))
  83                 return inode;
  84         inode->i_mode = parent->i_mode;
  85         inode->i_uid = parent->i_uid;
  86         inode->i_gid = parent->i_gid;
  87         inode->i_op = &ceph_snapdir_iops;
  88         inode->i_fop = &ceph_snapdir_fops;
  89         ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
  90         ci->i_rbytes = 0;
  91         return inode;
  92 }
  93
  94 const struct inode_operations ceph_file_iops = {
  95         .permission = ceph_permission,
  96         .setattr = ceph_setattr,
  97         .getattr = ceph_getattr,
  98         .listxattr = ceph_listxattr,
  99         .get_acl = ceph_get_acl,
 100         .set_acl = ceph_set_acl,
 101 };
 102
 103
 104 /*
 105  * We use a 'frag tree' to keep track of the MDS's directory fragments
 106  * for a given inode (usually there is just a single fragment).  We
 107  * need to know when a child frag is delegated to a new MDS, or when
 108  * it is flagged as replicated, so we can direct our requests
 109  * accordingly.
 110  */
 111
 112 /*
 113  * find/create a frag in the tree
 114  */
 115 static struct ceph_inode_frag *__get_or_create_frag(struct ceph_inode_info *ci,
 116                                                     u32 f)
 117 {
 118         struct rb_node **p;
 119         struct rb_node *parent = NULL;
 120         struct ceph_inode_frag *frag;
 121         int c;
 122
 123         p = &ci->i_fragtree.rb_node;
 124         while (*p) {
 125                 parent = *p;
 126                 frag = rb_entry(parent, struct ceph_inode_frag, node);
 127                 c = ceph_frag_compare(f, frag->frag);
 128                 if (c < 0)
 129                         p = &(*p)->rb_left;
 130                 else if (c > 0)
 131                         p = &(*p)->rb_right;
 132                 else
 133                         return frag;
 134         }
 135
 136         frag = kmalloc(sizeof(*frag), GFP_NOFS);
 137         if (!frag)
 138                 return ERR_PTR(-ENOMEM);
 139
 140         frag->frag = f;
 141         frag->split_by = 0;
 142         frag->mds = -1;
 143         frag->ndist = 0;
 144
 145         rb_link_node(&frag->node, parent, p);
 146         rb_insert_color(&frag->node, &ci->i_fragtree);
 147
 148         dout("get_or_create_frag added %llx.%llx frag %x\n",
 149              ceph_vinop(&ci->vfs_inode), f);
 150         return frag;
 151 }
 152
 153 /*
 154  * find a specific frag @f
 155  */
 156 struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci, u32 f)
 157 {
 158         struct rb_node *n = ci->i_fragtree.rb_node;
 159
 160         while (n) {
 161                 struct ceph_inode_frag *frag =
 162                         rb_entry(n, struct ceph_inode_frag, node);
 163                 int c = ceph_frag_compare(f, frag->frag);
 164                 if (c < 0)
 165                         n = n->rb_left;
 166                 else if (c > 0)
 167                         n = n->rb_right;
 168                 else
 169                         return frag;
 170         }
 171         return NULL;
 172 }
 173
 174 /*
 175  * Choose frag containing the given value @v.  If @pfrag is
 176  * specified, copy the frag delegation info to the caller if
 177  * it is present.
 178  */
 179 static u32 __ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
 180                               struct ceph_inode_frag *pfrag, int *found)
 181 {
 182         u32 t = ceph_frag_make(0, 0);
 183         struct ceph_inode_frag *frag;
 184         unsigned nway, i;
 185         u32 n;
 186
 187         if (found)
 188                 *found = 0;
 189
 190         while (1) {
 191                 WARN_ON(!ceph_frag_contains_value(t, v));
 192                 frag = __ceph_find_frag(ci, t);
 193                 if (!frag)
 194                         break; /* t is a leaf */
 195                 if (frag->split_by == 0) {
 196                         if (pfrag)
 197                                 memcpy(pfrag, frag, sizeof(*pfrag));
 198                         if (found)
 199                                 *found = 1;
 200                         break;
 201                 }
 202
 203                 /* choose child */
 204                 nway = 1 << frag->split_by;
 205                 dout("choose_frag(%x) %x splits by %d (%d ways)\n", v, t,
 206                      frag->split_by, nway);
 207                 for (i = 0; i < nway; i++) {
 208                         n = ceph_frag_make_child(t, frag->split_by, i);
 209                         if (ceph_frag_contains_value(n, v)) {
 210                                 t = n;
 211                                 break;
 212                         }
 213                 }
 214                 BUG_ON(i == nway);
 215         }
 216         dout("choose_frag(%x) = %x\n", v, t);
 217
 218         return t;
 219 }
 220
 221 u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
 222                      struct ceph_inode_frag *pfrag, int *found)
 223 {
 224         u32 ret;
 225         mutex_lock(&ci->i_fragtree_mutex);
 226         ret = __ceph_choose_frag(ci, v, pfrag, found);
 227         mutex_unlock(&ci->i_fragtree_mutex);
 228         return ret;
 229 }
 230
 231 /*
 232  * Process dirfrag (delegation) info from the mds.  Include leaf
 233  * fragment in tree ONLY if ndist > 0.  Otherwise, only
 234  * branches/splits are included in i_fragtree)
 235  */
 236 static int ceph_fill_dirfrag(struct inode *inode,
 237                              struct ceph_mds_reply_dirfrag *dirinfo)
 238 {
 239         struct ceph_inode_info *ci = ceph_inode(inode);
 240         struct ceph_inode_frag *frag;
 241         u32 id = le32_to_cpu(dirinfo->frag);
 242         int mds = le32_to_cpu(dirinfo->auth);
 243         int ndist = le32_to_cpu(dirinfo->ndist);
 244         int diri_auth = -1;
 245         int i;
 246         int err = 0;
 247
 248         spin_lock(&ci->i_ceph_lock);
 249         if (ci->i_auth_cap)
 250                 diri_auth = ci->i_auth_cap->mds;
 251         spin_unlock(&ci->i_ceph_lock);
 252
 253         if (mds == -1) /* CDIR_AUTH_PARENT */
 254                 mds = diri_auth;
 255
 256         mutex_lock(&ci->i_fragtree_mutex);
 257         if (ndist == 0 && mds == diri_auth) {
 258                 /* no delegation info needed. */
 259                 frag = __ceph_find_frag(ci, id);
 260                 if (!frag)
 261                         goto out;
 262                 if (frag->split_by == 0) {
 263                         /* tree leaf, remove */
 264                         dout("fill_dirfrag removed %llx.%llx frag %x"
 265                              " (no ref)\n", ceph_vinop(inode), id);
 266                         rb_erase(&frag->node, &ci->i_fragtree);
 267                         kfree(frag);
 268                 } else {
 269                         /* tree branch, keep and clear */
 270                         dout("fill_dirfrag cleared %llx.%llx frag %x"
 271                              " referral\n", ceph_vinop(inode), id);
 272                         frag->mds = -1;
 273                         frag->ndist = 0;
 274                 }
 275                 goto out;
 276         }
 277
 278
 279         /* find/add this frag to store mds delegation info */
 280         frag = __get_or_create_frag(ci, id);
 281         if (IS_ERR(frag)) {
 282                 /* this is not the end of the world; we can continue
 283                    with bad/inaccurate delegation info */
 284                 pr_err("fill_dirfrag ENOMEM on mds ref %llx.%llx fg %x\n",
 285                        ceph_vinop(inode), le32_to_cpu(dirinfo->frag));
 286                 err = -ENOMEM;
 287                 goto out;
 288         }
 289
 290         frag->mds = mds;
 291         frag->ndist = min_t(u32, ndist, CEPH_MAX_DIRFRAG_REP);
 292         for (i = 0; i < frag->ndist; i++)
 293                 frag->dist[i] = le32_to_cpu(dirinfo->dist[i]);
 294         dout("fill_dirfrag %llx.%llx frag %x ndist=%d\n",
 295              ceph_vinop(inode), frag->frag, frag->ndist);
 296
 297 out:
 298         mutex_unlock(&ci->i_fragtree_mutex);
 299         return err;
 300 }
 301
 302 static int frag_tree_split_cmp(const void *l, const void *r)
 303 {
 304         struct ceph_frag_tree_split *ls = (struct ceph_frag_tree_split*)l;
 305         struct ceph_frag_tree_split *rs = (struct ceph_frag_tree_split*)r;
 306         return ceph_frag_compare(le32_to_cpu(ls->frag),
 307                                  le32_to_cpu(rs->frag));
 308 }
 309
 310 static bool is_frag_child(u32 f, struct ceph_inode_frag *frag)
 311 {
 312         if (!frag)
 313                 return f == ceph_frag_make(0, 0);
 314         if (ceph_frag_bits(f) != ceph_frag_bits(frag->frag) + frag->split_by)
 315                 return false;
 316         return ceph_frag_contains_value(frag->frag, ceph_frag_value(f));
 317 }
 318
 319 static int ceph_fill_fragtree(struct inode *inode,
 320                               struct ceph_frag_tree_head *fragtree,
 321                               struct ceph_mds_reply_dirfrag *dirinfo)
 322 {
 323         struct ceph_inode_info *ci = ceph_inode(inode);
 324         struct ceph_inode_frag *frag, *prev_frag = NULL;
 325         struct rb_node *rb_node;
 326         unsigned i, split_by, nsplits;
 327         u32 id;
 328         bool update = false;
 329
 330         mutex_lock(&ci->i_fragtree_mutex);
 331         nsplits = le32_to_cpu(fragtree->nsplits);
 332         if (nsplits != ci->i_fragtree_nsplits) {
 333                 update = true;
 334         } else if (nsplits) {
 335                 i = prandom_u32() % nsplits;
 336                 id = le32_to_cpu(fragtree->splits[i].frag);
 337                 if (!__ceph_find_frag(ci, id))
 338                         update = true;
 339         } else if (!RB_EMPTY_ROOT(&ci->i_fragtree)) {
 340                 rb_node = rb_first(&ci->i_fragtree);
 341                 frag = rb_entry(rb_node, struct ceph_inode_frag, node);
 342                 if (frag->frag != ceph_frag_make(0, 0) || rb_next(rb_node))
 343                         update = true;
 344         }
 345         if (!update && dirinfo) {
 346                 id = le32_to_cpu(dirinfo->frag);
 347                 if (id != __ceph_choose_frag(ci, id, NULL, NULL))
 348                         update = true;
 349         }
 350         if (!update)
 351                 goto out_unlock;
 352
 353         if (nsplits > 1) {
 354                 sort(fragtree->splits, nsplits, sizeof(fragtree->splits[0]),
 355                      frag_tree_split_cmp, NULL);
 356         }
 357
 358         dout("fill_fragtree %llx.%llx\n", ceph_vinop(inode));
 359         rb_node = rb_first(&ci->i_fragtree);
 360         for (i = 0; i < nsplits; i++) {
 361                 id = le32_to_cpu(fragtree->splits[i].frag);
 362                 split_by = le32_to_cpu(fragtree->splits[i].by);
 363                 if (split_by == 0 || ceph_frag_bits(id) + split_by > 24) {
 364                         pr_err("fill_fragtree %llx.%llx invalid split %d/%u, "
 365                                "frag %x split by %d\n", ceph_vinop(inode),
 366                                i, nsplits, id, split_by);
 367                         continue;
 368                 }
 369                 frag = NULL;
 370                 while (rb_node) {
 371                         frag = rb_entry(rb_node, struct ceph_inode_frag, node);
 372                         if (ceph_frag_compare(frag->frag, id) >= 0) {
 373                                 if (frag->frag != id)
 374                                         frag = NULL;
 375                                 else
 376                                         rb_node = rb_next(rb_node);
 377                                 break;
 378                         }
 379                         rb_node = rb_next(rb_node);
 380                         /* delete stale split/leaf node */
 381                         if (frag->split_by > 0 ||
 382                             !is_frag_child(frag->frag, prev_frag)) {
 383                                 rb_erase(&frag->node, &ci->i_fragtree);
 384                                 if (frag->split_by > 0)
 385                                         ci->i_fragtree_nsplits--;
 386                                 kfree(frag);
 387                         }
 388                         frag = NULL;
 389                 }
 390                 if (!frag) {
 391                         frag = __get_or_create_frag(ci, id);
 392                         if (IS_ERR(frag))
 393                                 continue;
 394                 }
 395                 if (frag->split_by == 0)
 396                         ci->i_fragtree_nsplits++;
 397                 frag->split_by = split_by;
 398                 dout(" frag %x split by %d\n", frag->frag, frag->split_by);
 399                 prev_frag = frag;
 400         }
 401         while (rb_node) {
 402                 frag = rb_entry(rb_node, struct ceph_inode_frag, node);
 403                 rb_node = rb_next(rb_node);
 404                 /* delete stale split/leaf node */
 405                 if (frag->split_by > 0 ||
 406                     !is_frag_child(frag->frag, prev_frag)) {
 407                         rb_erase(&frag->node, &ci->i_fragtree);
 408                         if (frag->split_by > 0)
 409                                 ci->i_fragtree_nsplits--;
 410                         kfree(frag);
 411                 }
 412         }
 413 out_unlock:
 414         mutex_unlock(&ci->i_fragtree_mutex);
 415         return 0;
 416 }
 417
 418 /*
 419  * initialize a newly allocated inode.
 420  */
 421 struct inode *ceph_alloc_inode(struct super_block *sb)
 422 {
 423         struct ceph_inode_info *ci;
 424         int i;
 425
 426         ci = kmem_cache_alloc(ceph_inode_cachep, GFP_NOFS);
 427         if (!ci)
 428                 return NULL;
 429
 430         dout("alloc_inode %p\n", &ci->vfs_inode);
 431
 432         spin_lock_init(&ci->i_ceph_lock);
 433
 434         ci->i_version = 0;
 435         ci->i_inline_version = 0;
 436         ci->i_time_warp_seq = 0;
 437         ci->i_ceph_flags = 0;
 438         atomic64_set(&ci->i_ordered_count, 1);
 439         atomic64_set(&ci->i_release_count, 1);
 440         atomic64_set(&ci->i_complete_seq[0], 0);
 441         atomic64_set(&ci->i_complete_seq[1], 0);
 442         ci->i_symlink = NULL;
 443
 444         ci->i_max_bytes = 0;
 445         ci->i_max_files = 0;
 446
 447         memset(&ci->i_dir_layout, 0, sizeof(ci->i_dir_layout));
 448         RCU_INIT_POINTER(ci->i_layout.pool_ns, NULL);
 449
 450         ci->i_fragtree = RB_ROOT;
 451         mutex_init(&ci->i_fragtree_mutex);
 452
 453         ci->i_xattrs.blob = NULL;
 454         ci->i_xattrs.prealloc_blob = NULL;
 455         ci->i_xattrs.dirty = false;
 456         ci->i_xattrs.index = RB_ROOT;
 457         ci->i_xattrs.count = 0;
 458         ci->i_xattrs.names_size = 0;
 459         ci->i_xattrs.vals_size = 0;
 460         ci->i_xattrs.version = 0;
 461         ci->i_xattrs.index_version = 0;
 462
 463         ci->i_caps = RB_ROOT;
 464         ci->i_auth_cap = NULL;
 465         ci->i_dirty_caps = 0;
 466         ci->i_flushing_caps = 0;
 467         INIT_LIST_HEAD(&ci->i_dirty_item);
 468         INIT_LIST_HEAD(&ci->i_flushing_item);
 469         ci->i_prealloc_cap_flush = NULL;
 470         INIT_LIST_HEAD(&ci->i_cap_flush_list);
 471         init_waitqueue_head(&ci->i_cap_wq);
 472         ci->i_hold_caps_min = 0;
 473         ci->i_hold_caps_max = 0;
 474         INIT_LIST_HEAD(&ci->i_cap_delay_list);
 475         INIT_LIST_HEAD(&ci->i_cap_snaps);
 476         ci->i_head_snapc = NULL;
 477         ci->i_snap_caps = 0;
 478
 479         for (i = 0; i < CEPH_FILE_MODE_BITS; i++)
 480                 ci->i_nr_by_mode[i] = 0;
 481
 482         mutex_init(&ci->i_truncate_mutex);
 483         ci->i_truncate_seq = 0;
 484         ci->i_truncate_size = 0;
 485         ci->i_truncate_pending = 0;
 486
 487         ci->i_max_size = 0;
 488         ci->i_reported_size = 0;
 489         ci->i_wanted_max_size = 0;
 490         ci->i_requested_max_size = 0;
 491
 492         ci->i_pin_ref = 0;
 493         ci->i_rd_ref = 0;
 494         ci->i_rdcache_ref = 0;
 495         ci->i_wr_ref = 0;
 496         ci->i_wb_ref = 0;
 497         ci->i_wrbuffer_ref = 0;
 498         ci->i_wrbuffer_ref_head = 0;
 499         atomic_set(&ci->i_filelock_ref, 0);
 500         atomic_set(&ci->i_shared_gen, 1);
 501         ci->i_rdcache_gen = 0;
 502         ci->i_rdcache_revoking = 0;
 503
 504         INIT_LIST_HEAD(&ci->i_unsafe_dirops);
 505         INIT_LIST_HEAD(&ci->i_unsafe_iops);
 506         spin_lock_init(&ci->i_unsafe_lock);
 507
 508         ci->i_snap_realm = NULL;
 509         INIT_LIST_HEAD(&ci->i_snap_realm_item);
 510         INIT_LIST_HEAD(&ci->i_snap_flush_item);
 511
 512         INIT_WORK(&ci->i_work, ceph_inode_work);
 513         ci->i_work_mask = 0;
 514         memset(&ci->i_btime, '\0', sizeof(ci->i_btime));
 515
 516         ceph_fscache_inode_init(ci);
 517
 518         return &ci->vfs_inode;
 519 }
 520
 521 void ceph_free_inode(struct inode *inode)
 522 {
 523         struct ceph_inode_info *ci = ceph_inode(inode);
 524
 525         kfree(ci->i_symlink);
 526         kmem_cache_free(ceph_inode_cachep, ci);
 527 }
 528
 529 void ceph_evict_inode(struct inode *inode)
 530 {
 531         struct ceph_inode_info *ci = ceph_inode(inode);
 532         struct ceph_inode_frag *frag;
 533         struct rb_node *n;
 534
 535         dout("evict_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
 536
 537         truncate_inode_pages_final(&inode->i_data);
 538         clear_inode(inode);
 539
 540         ceph_fscache_unregister_inode_cookie(ci);
 541
 542         __ceph_remove_caps(ci);
 543
 544         if (__ceph_has_any_quota(ci))
 545                 ceph_adjust_quota_realms_count(inode, false);
 546
 547         /*
 548          * we may still have a snap_realm reference if there are stray
 549          * caps in i_snap_caps.
 550          */
 551         if (ci->i_snap_realm) {
 552                 struct ceph_mds_client *mdsc =
 553                                         ceph_inode_to_client(inode)->mdsc;
 554                 if (ceph_snap(inode) == CEPH_NOSNAP) {
 555                         struct ceph_snap_realm *realm = ci->i_snap_realm;
 556                         dout(" dropping residual ref to snap realm %p\n",
 557                              realm);
 558                         spin_lock(&realm->inodes_with_caps_lock);
 559                         list_del_init(&ci->i_snap_realm_item);
 560                         ci->i_snap_realm = NULL;
 561                         if (realm->ino == ci->i_vino.ino)
 562                                 realm->inode = NULL;
 563                         spin_unlock(&realm->inodes_with_caps_lock);
 564                         ceph_put_snap_realm(mdsc, realm);
 565                 } else {
 566                         ceph_put_snapid_map(mdsc, ci->i_snapid_map);
 567                         ci->i_snap_realm = NULL;
 568                 }
 569         }
 570
 571         while ((n = rb_first(&ci->i_fragtree)) != NULL) {
 572                 frag = rb_entry(n, struct ceph_inode_frag, node);
 573                 rb_erase(n, &ci->i_fragtree);
 574                 kfree(frag);
 575         }
 576         ci->i_fragtree_nsplits = 0;
 577
 578         __ceph_destroy_xattrs(ci);
 579         if (ci->i_xattrs.blob)
 580                 ceph_buffer_put(ci->i_xattrs.blob);
 581         if (ci->i_xattrs.prealloc_blob)
 582                 ceph_buffer_put(ci->i_xattrs.prealloc_blob);
 583
 584         ceph_put_string(rcu_dereference_raw(ci->i_layout.pool_ns));
 585 }
 586
 587 static inline blkcnt_t calc_inode_blocks(u64 size)
 588 {
 589         return (size + (1<<9) - 1) >> 9;
 590 }
 591
 592 /*
 593  * Helpers to fill in size, ctime, mtime, and atime.  We have to be
 594  * careful because either the client or MDS may have more up to date
 595  * info, depending on which capabilities are held, and whether
 596  * time_warp_seq or truncate_seq have increased.  (Ordinarily, mtime
 597  * and size are monotonically increasing, except when utimes() or
 598  * truncate() increments the corresponding _seq values.)
 599  */
 600 int ceph_fill_file_size(struct inode *inode, int issued,
 601                         u32 truncate_seq, u64 truncate_size, u64 size)
 602 {
 603         struct ceph_inode_info *ci = ceph_inode(inode);
 604         int queue_trunc = 0;
 605
 606         if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) > 0 ||
 607             (truncate_seq == ci->i_truncate_seq && size > inode->i_size)) {
 608                 dout("size %lld -> %llu\n", inode->i_size, size);
 609                 if (size > 0 && S_ISDIR(inode->i_mode)) {
 610                         pr_err("fill_file_size non-zero size for directory\n");
 611                         size = 0;
 612                 }
 613                 i_size_write(inode, size);
 614                 inode->i_blocks = calc_inode_blocks(size);
 615                 ci->i_reported_size = size;
 616                 if (truncate_seq != ci->i_truncate_seq) {
 617                         dout("truncate_seq %u -> %u\n",
 618                              ci->i_truncate_seq, truncate_seq);
 619                         ci->i_truncate_seq = truncate_seq;
 620
 621                         /* the MDS should have revoked these caps */
 622                         WARN_ON_ONCE(issued & (CEPH_CAP_FILE_EXCL |
 623                                                CEPH_CAP_FILE_RD |
 624                                                CEPH_CAP_FILE_WR |
 625                                                CEPH_CAP_FILE_LAZYIO));
 626                         /*
 627                          * If we hold relevant caps, or in the case where we're
 628                          * not the only client referencing this file and we
 629                          * don't hold those caps, then we need to check whether
 630                          * the file is either opened or mmaped
 631                          */
 632                         if ((issued & (CEPH_CAP_FILE_CACHE|
 633                                        CEPH_CAP_FILE_BUFFER)) ||
 634                             mapping_mapped(inode->i_mapping) ||
 635                             __ceph_caps_file_wanted(ci)) {
 636                                 ci->i_truncate_pending++;
 637                                 queue_trunc = 1;
 638                         }
 639                 }
 640         }
 641         if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) >= 0 &&
 642             ci->i_truncate_size != truncate_size) {
 643                 dout("truncate_size %lld -> %llu\n", ci->i_truncate_size,
 644                      truncate_size);
 645                 ci->i_truncate_size = truncate_size;
 646         }
 647
 648         if (queue_trunc)
 649                 ceph_fscache_invalidate(inode);
 650
 651         return queue_trunc;
 652 }
 653
 654 void ceph_fill_file_time(struct inode *inode, int issued,
 655                          u64 time_warp_seq, struct timespec64 *ctime,
 656                          struct timespec64 *mtime, struct timespec64 *atime)
 657 {
 658         struct ceph_inode_info *ci = ceph_inode(inode);
 659         int warn = 0;
 660
 661         if (issued & (CEPH_CAP_FILE_EXCL|
 662                       CEPH_CAP_FILE_WR|
 663                       CEPH_CAP_FILE_BUFFER|
 664                       CEPH_CAP_AUTH_EXCL|
 665                       CEPH_CAP_XATTR_EXCL)) {
 666                 if (ci->i_version == 0 ||
 667                     timespec64_compare(ctime, &inode->i_ctime) > 0) {
 668                         dout("ctime %lld.%09ld -> %lld.%09ld inc w/ cap\n",
 669                              inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
 670                              ctime->tv_sec, ctime->tv_nsec);
 671                         inode->i_ctime = *ctime;
 672                 }
 673                 if (ci->i_version == 0 ||
 674                     ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) > 0) {
 675                         /* the MDS did a utimes() */
 676                         dout("mtime %lld.%09ld -> %lld.%09ld "
 677                              "tw %d -> %d\n",
 678                              inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
 679                              mtime->tv_sec, mtime->tv_nsec,
 680                              ci->i_time_warp_seq, (int)time_warp_seq);
 681
 682                         inode->i_mtime = *mtime;
 683                         inode->i_atime = *atime;
 684                         ci->i_time_warp_seq = time_warp_seq;
 685                 } else if (time_warp_seq == ci->i_time_warp_seq) {
 686                         /* nobody did utimes(); take the max */
 687                         if (timespec64_compare(mtime, &inode->i_mtime) > 0) {
 688                                 dout("mtime %lld.%09ld -> %lld.%09ld inc\n",
 689                                      inode->i_mtime.tv_sec,
 690                                      inode->i_mtime.tv_nsec,
 691                                      mtime->tv_sec, mtime->tv_nsec);
 692                                 inode->i_mtime = *mtime;
 693                         }
 694                         if (timespec64_compare(atime, &inode->i_atime) > 0) {
 695                                 dout("atime %lld.%09ld -> %lld.%09ld inc\n",
 696                                      inode->i_atime.tv_sec,
 697                                      inode->i_atime.tv_nsec,
 698                                      atime->tv_sec, atime->tv_nsec);
 699                                 inode->i_atime = *atime;
 700                         }
 701                 } else if (issued & CEPH_CAP_FILE_EXCL) {
 702                         /* we did a utimes(); ignore mds values */
 703                 } else {
 704                         warn = 1;
 705                 }
 706         } else {
 707                 /* we have no write|excl caps; whatever the MDS says is true */
 708                 if (ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) >= 0) {
 709                         inode->i_ctime = *ctime;
 710                         inode->i_mtime = *mtime;
 711                         inode->i_atime = *atime;
 712                         ci->i_time_warp_seq = time_warp_seq;
 713                 } else {
 714                         warn = 1;
 715                 }
 716         }
 717         if (warn) /* time_warp_seq shouldn't go backwards */
 718                 dout("%p mds time_warp_seq %llu < %u\n",
 719                      inode, time_warp_seq, ci->i_time_warp_seq);
 720 }
 721
 722 /*
 723  * Populate an inode based on info from mds.  May be called on new or
 724  * existing inodes.
 725  */
 726 static int fill_inode(struct inode *inode, struct page *locked_page,
 727                       struct ceph_mds_reply_info_in *iinfo,
 728                       struct ceph_mds_reply_dirfrag *dirinfo,
 729                       struct ceph_mds_session *session,
 730                       unsigned long ttl_from, int cap_fmode,
 731                       struct ceph_cap_reservation *caps_reservation)
 732 {
 733         struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
 734         struct ceph_mds_reply_inode *info = iinfo->in;
 735         struct ceph_inode_info *ci = ceph_inode(inode);
 736         int issued, new_issued, info_caps;
 737         struct timespec64 mtime, atime, ctime;
 738         struct ceph_buffer *xattr_blob = NULL;
 739         struct ceph_buffer *old_blob = NULL;
 740         struct ceph_string *pool_ns = NULL;
 741         struct ceph_cap *new_cap = NULL;
 742         int err = 0;
 743         bool wake = false;
 744         bool queue_trunc = false;
 745         bool new_version = false;
 746         bool fill_inline = false;
 747
 748         dout("fill_inode %p ino %llx.%llx v %llu had %llu\n",
 749              inode, ceph_vinop(inode), le64_to_cpu(info->version),
 750              ci->i_version);
 751
 752         info_caps = le32_to_cpu(info->cap.caps);
 753
 754         /* prealloc new cap struct */
 755         if (info_caps && ceph_snap(inode) == CEPH_NOSNAP)
 756                 new_cap = ceph_get_cap(mdsc, caps_reservation);
 757
 758         /*
 759          * prealloc xattr data, if it looks like we'll need it.  only
 760          * if len > 4 (meaning there are actually xattrs; the first 4
 761          * bytes are the xattr count).
 762          */
 763         if (iinfo->xattr_len > 4) {
 764                 xattr_blob = ceph_buffer_new(iinfo->xattr_len, GFP_NOFS);
 765                 if (!xattr_blob)
 766                         pr_err("fill_inode ENOMEM xattr blob %d bytes\n",
 767                                iinfo->xattr_len);
 768         }
 769
 770         if (iinfo->pool_ns_len > 0)
 771                 pool_ns = ceph_find_or_create_string(iinfo->pool_ns_data,
 772                                                      iinfo->pool_ns_len);
 773
 774         if (ceph_snap(inode) != CEPH_NOSNAP && !ci->i_snapid_map)
 775                 ci->i_snapid_map = ceph_get_snapid_map(mdsc, ceph_snap(inode));
 776
 777         spin_lock(&ci->i_ceph_lock);
 778
 779         /*
 780          * provided version will be odd if inode value is projected,
 781          * even if stable.  skip the update if we have newer stable
 782          * info (ours>=theirs, e.g. due to racing mds replies), unless
 783          * we are getting projected (unstable) info (in which case the
 784          * version is odd, and we want ours>theirs).
 785          *   us   them
 786          *   2    2     skip
 787          *   3    2     skip
 788          *   3    3     update
 789          */
 790         if (ci->i_version == 0 ||
 791             ((info->cap.flags & CEPH_CAP_FLAG_AUTH) &&
 792              le64_to_cpu(info->version) > (ci->i_version & ~1)))
 793                 new_version = true;
 794
 795         /* Update change_attribute */
 796         inode_set_max_iversion_raw(inode, iinfo->change_attr);
 797
 798         __ceph_caps_issued(ci, &issued);
 799         issued |= __ceph_caps_dirty(ci);
 800         new_issued = ~issued & info_caps;
 801
 802         /* update inode */
 803         inode->i_rdev = le32_to_cpu(info->rdev);
 804         inode->i_blkbits = fls(le32_to_cpu(info->layout.fl_stripe_unit)) - 1;
 805
 806         __ceph_update_quota(ci, iinfo->max_bytes, iinfo->max_files);
 807
 808         if ((new_version || (new_issued & CEPH_CAP_AUTH_SHARED)) &&
 809             (issued & CEPH_CAP_AUTH_EXCL) == 0) {
 810                 inode->i_mode = le32_to_cpu(info->mode);
 811                 inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(info->uid));
 812                 inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(info->gid));
 813                 dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
 814                      from_kuid(&init_user_ns, inode->i_uid),
 815                      from_kgid(&init_user_ns, inode->i_gid));
 816                 ceph_decode_timespec64(&ci->i_btime, &iinfo->btime);
 817                 ceph_decode_timespec64(&ci->i_snap_btime, &iinfo->snap_btime);
 818         }
 819
 820         if ((new_version || (new_issued & CEPH_CAP_LINK_SHARED)) &&
 821             (issued & CEPH_CAP_LINK_EXCL) == 0)
 822                 set_nlink(inode, le32_to_cpu(info->nlink));
 823
 824         if (new_version || (new_issued & CEPH_CAP_ANY_RD)) {
 825                 /* be careful with mtime, atime, size */
 826                 ceph_decode_timespec64(&atime, &info->atime);
 827                 ceph_decode_timespec64(&mtime, &info->mtime);
 828                 ceph_decode_timespec64(&ctime, &info->ctime);
 829                 ceph_fill_file_time(inode, issued,
 830                                 le32_to_cpu(info->time_warp_seq),
 831                                 &ctime, &mtime, &atime);
 832         }
 833
 834         if (new_version || (info_caps & CEPH_CAP_FILE_SHARED)) {
 835                 ci->i_files = le64_to_cpu(info->files);
 836                 ci->i_subdirs = le64_to_cpu(info->subdirs);
 837         }
 838
 839         if (new_version ||
 840             (new_issued & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
 841                 s64 old_pool = ci->i_layout.pool_id;
 842                 struct ceph_string *old_ns;
 843
 844                 ceph_file_layout_from_legacy(&ci->i_layout, &info->layout);
 845                 old_ns = rcu_dereference_protected(ci->i_layout.pool_ns,
 846                                         lockdep_is_held(&ci->i_ceph_lock));
 847                 rcu_assign_pointer(ci->i_layout.pool_ns, pool_ns);
 848
 849                 if (ci->i_layout.pool_id != old_pool || pool_ns != old_ns)
 850                         ci->i_ceph_flags &= ~CEPH_I_POOL_PERM;
 851
 852                 pool_ns = old_ns;
 853
 854                 queue_trunc = ceph_fill_file_size(inode, issued,
 855                                         le32_to_cpu(info->truncate_seq),
 856                                         le64_to_cpu(info->truncate_size),
 857                                         le64_to_cpu(info->size));
 858                 /* only update max_size on auth cap */
 859                 if ((info->cap.flags & CEPH_CAP_FLAG_AUTH) &&
 860                     ci->i_max_size != le64_to_cpu(info->max_size)) {
 861                         dout("max_size %lld -> %llu\n", ci->i_max_size,
 862                                         le64_to_cpu(info->max_size));
 863                         ci->i_max_size = le64_to_cpu(info->max_size);
 864                 }
 865         }
 866
 867         /* layout and rstat are not tracked by capability, update them if
 868          * the inode info is from auth mds */
 869         if (new_version || (info->cap.flags & CEPH_CAP_FLAG_AUTH)) {
 870                 if (S_ISDIR(inode->i_mode)) {
 871                         ci->i_dir_layout = iinfo->dir_layout;
 872                         ci->i_rbytes = le64_to_cpu(info->rbytes);
 873                         ci->i_rfiles = le64_to_cpu(info->rfiles);
 874                         ci->i_rsubdirs = le64_to_cpu(info->rsubdirs);
 875                         ci->i_dir_pin = iinfo->dir_pin;
 876                         ceph_decode_timespec64(&ci->i_rctime, &info->rctime);
 877                 }
 878         }
 879
 880         /* xattrs */
 881         /* note that if i_xattrs.len <= 4, i_xattrs.data will still be NULL. */
 882         if ((ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))  &&
 883             le64_to_cpu(info->xattr_version) > ci->i_xattrs.version) {
 884                 if (ci->i_xattrs.blob)
 885                         old_blob = ci->i_xattrs.blob;
 886                 ci->i_xattrs.blob = xattr_blob;
 887                 if (xattr_blob)
 888                         memcpy(ci->i_xattrs.blob->vec.iov_base,
 889                                iinfo->xattr_data, iinfo->xattr_len);
 890                 ci->i_xattrs.version = le64_to_cpu(info->xattr_version);
 891                 ceph_forget_all_cached_acls(inode);
 892                 ceph_security_invalidate_secctx(inode);
 893                 xattr_blob = NULL;
 894         }
 895
 896         /* finally update i_version */
 897         if (le64_to_cpu(info->version) > ci->i_version)
 898                 ci->i_version = le64_to_cpu(info->version);
 899
 900         inode->i_mapping->a_ops = &ceph_aops;
 901
 902         switch (inode->i_mode & S_IFMT) {
 903         case S_IFIFO:
 904         case S_IFBLK:
 905         case S_IFCHR:
 906         case S_IFSOCK:
 907                 inode->i_blkbits = PAGE_SHIFT;
 908                 init_special_inode(inode, inode->i_mode, inode->i_rdev);
 909                 inode->i_op = &ceph_file_iops;
 910                 break;
 911         case S_IFREG:
 912                 inode->i_op = &ceph_file_iops;
 913                 inode->i_fop = &ceph_file_fops;
 914                 break;
 915         case S_IFLNK:
 916                 inode->i_op = &ceph_symlink_iops;
 917                 if (!ci->i_symlink) {
 918                         u32 symlen = iinfo->symlink_len;
 919                         char *sym;
 920
 921                         spin_unlock(&ci->i_ceph_lock);
 922
 923                         if (symlen != i_size_read(inode)) {
 924                                 pr_err("fill_inode %llx.%llx BAD symlink "
 925                                         "size %lld\n", ceph_vinop(inode),
 926                                         i_size_read(inode));
 927                                 i_size_write(inode, symlen);
 928                                 inode->i_blocks = calc_inode_blocks(symlen);
 929                         }
 930
 931                         err = -ENOMEM;
 932                         sym = kstrndup(iinfo->symlink, symlen, GFP_NOFS);
 933                         if (!sym)
 934                                 goto out;
 935
 936                         spin_lock(&ci->i_ceph_lock);
 937                         if (!ci->i_symlink)
 938                                 ci->i_symlink = sym;
 939                         else
 940                                 kfree(sym); /* lost a race */
 941                 }
 942                 inode->i_link = ci->i_symlink;
 943                 break;
 944         case S_IFDIR:
 945                 inode->i_op = &ceph_dir_iops;
 946                 inode->i_fop = &ceph_dir_fops;
 947                 break;
 948         default:
 949                 pr_err("fill_inode %llx.%llx BAD mode 0%o\n",
 950                        ceph_vinop(inode), inode->i_mode);
 951         }
 952
 953         /* were we issued a capability? */
 954         if (info_caps) {
 955                 if (ceph_snap(inode) == CEPH_NOSNAP) {
 956                         ceph_add_cap(inode, session,
 957                                      le64_to_cpu(info->cap.cap_id),
 958                                      cap_fmode, info_caps,
 959                                      le32_to_cpu(info->cap.wanted),
 960                                      le32_to_cpu(info->cap.seq),
 961                                      le32_to_cpu(info->cap.mseq),
 962                                      le64_to_cpu(info->cap.realm),
 963                                      info->cap.flags, &new_cap);
 964
 965                         /* set dir completion flag? */
 966                         if (S_ISDIR(inode->i_mode) &&
 967                             ci->i_files == 0 && ci->i_subdirs == 0 &&
 968                             (info_caps & CEPH_CAP_FILE_SHARED) &&
 969                             (issued & CEPH_CAP_FILE_EXCL) == 0 &&
 970                             !__ceph_dir_is_complete(ci)) {
 971                                 dout(" marking %p complete (empty)\n", inode);
 972                                 i_size_write(inode, 0);
 973                                 __ceph_dir_set_complete(ci,
 974                                         atomic64_read(&ci->i_release_count),
 975                                         atomic64_read(&ci->i_ordered_count));
 976                         }
 977
 978                         wake = true;
 979                 } else {
 980                         dout(" %p got snap_caps %s\n", inode,
 981                              ceph_cap_string(info_caps));
 982                         ci->i_snap_caps |= info_caps;
 983                         if (cap_fmode >= 0)
 984                                 __ceph_get_fmode(ci, cap_fmode);
 985                 }
 986         } else if (cap_fmode >= 0) {
 987                 pr_warn("mds issued no caps on %llx.%llx\n",
 988                            ceph_vinop(inode));
 989                 __ceph_get_fmode(ci, cap_fmode);
 990         }
 991
 992         if (iinfo->inline_version > 0 &&
 993             iinfo->inline_version >= ci->i_inline_version) {
 994                 int cache_caps = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
 995                 ci->i_inline_version = iinfo->inline_version;
 996                 if (ci->i_inline_version != CEPH_INLINE_NONE &&
 997                     (locked_page || (info_caps & cache_caps)))
 998                         fill_inline = true;
 999         }
1000
1001         spin_unlock(&ci->i_ceph_lock);
1002
1003         if (fill_inline)
1004                 ceph_fill_inline_data(inode, locked_page,
1005                                       iinfo->inline_data, iinfo->inline_len);
1006
1007         if (wake)
1008                 wake_up_all(&ci->i_cap_wq);
1009
1010         /* queue truncate if we saw i_size decrease */
1011         if (queue_trunc)
1012                 ceph_queue_vmtruncate(inode);
1013
1014         /* populate frag tree */
1015         if (S_ISDIR(inode->i_mode))
1016                 ceph_fill_fragtree(inode, &info->fragtree, dirinfo);
1017
1018         /* update delegation info? */
1019         if (dirinfo)
1020                 ceph_fill_dirfrag(inode, dirinfo);
1021
1022         err = 0;
1023 out:
1024         if (new_cap)
1025                 ceph_put_cap(mdsc, new_cap);
1026         ceph_buffer_put(old_blob);
1027         ceph_buffer_put(xattr_blob);
1028         ceph_put_string(pool_ns);
1029         return err;
1030 }
1031
1032 /*
1033  * caller should hold session s_mutex and dentry->d_lock.
1034  */
1035 static void __update_dentry_lease(struct inode *dir, struct dentry *dentry,
1036                                   struct ceph_mds_reply_lease *lease,
1037                                   struct ceph_mds_session *session,
1038                                   unsigned long from_time,
1039                                   struct ceph_mds_session **old_lease_session)
1040 {
1041         struct ceph_dentry_info *di = ceph_dentry(dentry);
1042         long unsigned duration = le32_to_cpu(lease->duration_ms);
1043         long unsigned ttl = from_time + (duration * HZ) / 1000;
1044         long unsigned half_ttl = from_time + (duration * HZ / 2) / 1000;
1045
1046         dout("update_dentry_lease %p duration %lu ms ttl %lu\n",
1047              dentry, duration, ttl);
1048
1049         /* only track leases on regular dentries */
1050         if (ceph_snap(dir) != CEPH_NOSNAP)
1051                 return;
1052
1053         di->lease_shared_gen = atomic_read(&ceph_inode(dir)->i_shared_gen);
1054         if (duration == 0) {
1055                 __ceph_dentry_dir_lease_touch(di);
1056                 return;
1057         }
1058
1059         if (di->lease_gen == session->s_cap_gen &&
1060             time_before(ttl, di->time))
1061                 return;  /* we already have a newer lease. */
1062
1063         if (di->lease_session && di->lease_session != session) {
1064                 *old_lease_session = di->lease_session;
1065                 di->lease_session = NULL;
1066         }
1067
1068         if (!di->lease_session)
1069                 di->lease_session = ceph_get_mds_session(session);
1070         di->lease_gen = session->s_cap_gen;
1071         di->lease_seq = le32_to_cpu(lease->seq);
1072         di->lease_renew_after = half_ttl;
1073         di->lease_renew_from = 0;
1074         di->time = ttl;
1075
1076         __ceph_dentry_lease_touch(di);
1077 }
1078
1079 static inline void update_dentry_lease(struct inode *dir, struct dentry *dentry,
1080                                         struct ceph_mds_reply_lease *lease,
1081                                         struct ceph_mds_session *session,
1082                                         unsigned long from_time)
1083 {
1084         struct ceph_mds_session *old_lease_session = NULL;
1085         spin_lock(&dentry->d_lock);
1086         __update_dentry_lease(dir, dentry, lease, session, from_time,
1087                               &old_lease_session);
1088         spin_unlock(&dentry->d_lock);
1089         if (old_lease_session)
1090                 ceph_put_mds_session(old_lease_session);
1091 }
1092
1093 /*
1094  * update dentry lease without having parent inode locked
1095  */
1096 static void update_dentry_lease_careful(struct dentry *dentry,
1097                                         struct ceph_mds_reply_lease *lease,
1098                                         struct ceph_mds_session *session,
1099                                         unsigned long from_time,
1100                                         char *dname, u32 dname_len,
1101                                         struct ceph_vino *pdvino,
1102                                         struct ceph_vino *ptvino)
1103
1104 {
1105         struct inode *dir;
1106         struct ceph_mds_session *old_lease_session = NULL;
1107
1108         spin_lock(&dentry->d_lock);
1109         /* make sure dentry's name matches target */
1110         if (dentry->d_name.len != dname_len ||
1111             memcmp(dentry->d_name.name, dname, dname_len))
1112                 goto out_unlock;
1113
1114         dir = d_inode(dentry->d_parent);
1115         /* make sure parent matches dvino */
1116         if (!ceph_ino_compare(dir, pdvino))
1117                 goto out_unlock;
1118
1119         /* make sure dentry's inode matches target. NULL ptvino means that
1120          * we expect a negative dentry */
1121         if (ptvino) {
1122                 if (d_really_is_negative(dentry))
1123                         goto out_unlock;
1124                 if (!ceph_ino_compare(d_inode(dentry), ptvino))
1125                         goto out_unlock;
1126         } else {
1127                 if (d_really_is_positive(dentry))
1128                         goto out_unlock;
1129         }
1130
1131         __update_dentry_lease(dir, dentry, lease, session,
1132                               from_time, &old_lease_session);
1133 out_unlock:
1134         spin_unlock(&dentry->d_lock);
1135         if (old_lease_session)
1136                 ceph_put_mds_session(old_lease_session);
1137 }
1138
1139 /*
1140  * splice a dentry to an inode.
1141  * caller must hold directory i_mutex for this to be safe.
1142  */
1143 static int splice_dentry(struct dentry **pdn, struct inode *in)
1144 {
1145         struct dentry *dn = *pdn;
1146         struct dentry *realdn;
1147
1148         BUG_ON(d_inode(dn));
1149
1150         if (S_ISDIR(in->i_mode)) {
1151                 /* If inode is directory, d_splice_alias() below will remove
1152                  * 'realdn' from its origin parent. We need to ensure that
1153                  * origin parent's readdir cache will not reference 'realdn'
1154                  */
1155                 realdn = d_find_any_alias(in);
1156                 if (realdn) {
1157                         struct ceph_dentry_info *di = ceph_dentry(realdn);
1158                         spin_lock(&realdn->d_lock);
1159
1160                         realdn->d_op->d_prune(realdn);
1161
1162                         di->time = jiffies;
1163                         di->lease_shared_gen = 0;
1164                         di->offset = 0;
1165
1166                         spin_unlock(&realdn->d_lock);
1167                         dput(realdn);
1168                 }
1169         }
1170
1171         /* dn must be unhashed */
1172         if (!d_unhashed(dn))
1173                 d_drop(dn);
1174         realdn = d_splice_alias(in, dn);
1175         if (IS_ERR(realdn)) {
1176                 pr_err("splice_dentry error %ld %p inode %p ino %llx.%llx\n",
1177                        PTR_ERR(realdn), dn, in, ceph_vinop(in));
1178                 return PTR_ERR(realdn);
1179         }
1180
1181         if (realdn) {
1182                 dout("dn %p (%d) spliced with %p (%d) "
1183                      "inode %p ino %llx.%llx\n",
1184                      dn, d_count(dn),
1185                      realdn, d_count(realdn),
1186                      d_inode(realdn), ceph_vinop(d_inode(realdn)));
1187                 dput(dn);
1188                 *pdn = realdn;
1189         } else {
1190                 BUG_ON(!ceph_dentry(dn));
1191                 dout("dn %p attached to %p ino %llx.%llx\n",
1192                      dn, d_inode(dn), ceph_vinop(d_inode(dn)));
1193         }
1194         return 0;
1195 }
1196
1197 /*
1198  * Incorporate results into the local cache.  This is either just
1199  * one inode, or a directory, dentry, and possibly linked-to inode (e.g.,
1200  * after a lookup).
1201  *
1202  * A reply may contain
1203  *         a directory inode along with a dentry.
1204  *  and/or a target inode
1205  *
1206  * Called with snap_rwsem (read).
1207  */
1208 int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req)
1209 {
1210         struct ceph_mds_session *session = req->r_session;
1211         struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1212         struct inode *in = NULL;
1213         struct ceph_vino tvino, dvino;
1214         struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
1215         int err = 0;
1216
1217         dout("fill_trace %p is_dentry %d is_target %d\n", req,
1218              rinfo->head->is_dentry, rinfo->head->is_target);
1219
1220         if (!rinfo->head->is_target && !rinfo->head->is_dentry) {
1221                 dout("fill_trace reply is empty!\n");
1222                 if (rinfo->head->result == 0 && req->r_parent)
1223                         ceph_invalidate_dir_request(req);
1224                 return 0;
1225         }
1226
1227         if (rinfo->head->is_dentry) {
1228                 struct inode *dir = req->r_parent;
1229
1230                 if (dir) {
1231                         err = fill_inode(dir, NULL,
1232                                          &rinfo->diri, rinfo->dirfrag,
1233                                          session, req->r_request_started, -1,
1234                                          &req->r_caps_reservation);
1235                         if (err < 0)
1236                                 goto done;
1237                 } else {
1238                         WARN_ON_ONCE(1);
1239                 }
1240
1241                 if (dir && req->r_op == CEPH_MDS_OP_LOOKUPNAME &&
1242                     test_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags) &&
1243                     !test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
1244                         struct qstr dname;
1245                         struct dentry *dn, *parent;
1246
1247                         BUG_ON(!rinfo->head->is_target);
1248                         BUG_ON(req->r_dentry);
1249
1250                         parent = d_find_any_alias(dir);
1251                         BUG_ON(!parent);
1252
1253                         dname.name = rinfo->dname;
1254                         dname.len = rinfo->dname_len;
1255                         dname.hash = full_name_hash(parent, dname.name, dname.len);
1256                         tvino.ino = le64_to_cpu(rinfo->targeti.in->ino);
1257                         tvino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
1258 retry_lookup:
1259                         dn = d_lookup(parent, &dname);
1260                         dout("d_lookup on parent=%p name=%.*s got %p\n",
1261                              parent, dname.len, dname.name, dn);
1262
1263                         if (!dn) {
1264                                 dn = d_alloc(parent, &dname);
1265                                 dout("d_alloc %p '%.*s' = %p\n", parent,
1266                                      dname.len, dname.name, dn);
1267                                 if (!dn) {
1268                                         dput(parent);
1269                                         err = -ENOMEM;
1270                                         goto done;
1271                                 }
1272                                 err = 0;
1273                         } else if (d_really_is_positive(dn) &&
1274                                    (ceph_ino(d_inode(dn)) != tvino.ino ||
1275                                     ceph_snap(d_inode(dn)) != tvino.snap)) {
1276                                 dout(" dn %p points to wrong inode %p\n",
1277                                      dn, d_inode(dn));
1278                                 ceph_dir_clear_ordered(dir);
1279                                 d_delete(dn);
1280                                 dput(dn);
1281                                 goto retry_lookup;
1282                         }
1283
1284                         req->r_dentry = dn;
1285                         dput(parent);
1286                 }
1287         }
1288
1289         if (rinfo->head->is_target) {
1290                 tvino.ino = le64_to_cpu(rinfo->targeti.in->ino);
1291                 tvino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
1292
1293                 in = ceph_get_inode(sb, tvino);
1294                 if (IS_ERR(in)) {
1295                         err = PTR_ERR(in);
1296                         goto done;
1297                 }
1298                 req->r_target_inode = in;
1299
1300                 err = fill_inode(in, req->r_locked_page, &rinfo->targeti, NULL,
1301                                 session, req->r_request_started,
1302                                 (!test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags) &&
1303                                 rinfo->head->result == 0) ?  req->r_fmode : -1,
1304                                 &req->r_caps_reservation);
1305                 if (err < 0) {
1306                         pr_err("fill_inode badness %p %llx.%llx\n",
1307                                 in, ceph_vinop(in));
1308                         goto done;
1309                 }
1310         }
1311
1312         /*
1313          * ignore null lease/binding on snapdir ENOENT, or else we
1314          * will have trouble splicing in the virtual snapdir later
1315          */
1316         if (rinfo->head->is_dentry &&
1317             !test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags) &&
1318             test_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags) &&
1319             (rinfo->head->is_target || strncmp(req->r_dentry->d_name.name,
1320                                                fsc->mount_options->snapdir_name,
1321                                                req->r_dentry->d_name.len))) {
1322                 /*
1323                  * lookup link rename   : null -> possibly existing inode
1324                  * mknod symlink mkdir  : null -> new inode
1325                  * unlink               : linked -> null
1326                  */
1327                 struct inode *dir = req->r_parent;
1328                 struct dentry *dn = req->r_dentry;
1329                 bool have_dir_cap, have_lease;
1330
1331                 BUG_ON(!dn);
1332                 BUG_ON(!dir);
1333                 BUG_ON(d_inode(dn->d_parent) != dir);
1334
1335                 dvino.ino = le64_to_cpu(rinfo->diri.in->ino);
1336                 dvino.snap = le64_to_cpu(rinfo->diri.in->snapid);
1337
1338                 BUG_ON(ceph_ino(dir) != dvino.ino);
1339                 BUG_ON(ceph_snap(dir) != dvino.snap);
1340
1341                 /* do we have a lease on the whole dir? */
1342                 have_dir_cap =
1343                         (le32_to_cpu(rinfo->diri.in->cap.caps) &
1344                          CEPH_CAP_FILE_SHARED);
1345
1346                 /* do we have a dn lease? */
1347                 have_lease = have_dir_cap ||
1348                         le32_to_cpu(rinfo->dlease->duration_ms);
1349                 if (!have_lease)
1350                         dout("fill_trace  no dentry lease or dir cap\n");
1351
1352                 /* rename? */
1353                 if (req->r_old_dentry && req->r_op == CEPH_MDS_OP_RENAME) {
1354                         struct inode *olddir = req->r_old_dentry_dir;
1355                         BUG_ON(!olddir);
1356
1357                         dout(" src %p '%pd' dst %p '%pd'\n",
1358                              req->r_old_dentry,
1359                              req->r_old_dentry,
1360                              dn, dn);
1361                         dout("fill_trace doing d_move %p -> %p\n",
1362                              req->r_old_dentry, dn);
1363
1364                         /* d_move screws up sibling dentries' offsets */
1365                         ceph_dir_clear_ordered(dir);
1366                         ceph_dir_clear_ordered(olddir);
1367
1368                         d_move(req->r_old_dentry, dn);
1369                         dout(" src %p '%pd' dst %p '%pd'\n",
1370                              req->r_old_dentry,
1371                              req->r_old_dentry,
1372                              dn, dn);
1373
1374                         /* ensure target dentry is invalidated, despite
1375                            rehashing bug in vfs_rename_dir */
1376                         ceph_invalidate_dentry_lease(dn);
1377
1378                         dout("dn %p gets new offset %lld\n", req->r_old_dentry,
1379                              ceph_dentry(req->r_old_dentry)->offset);
1380
1381                         /* swap r_dentry and r_old_dentry in case that
1382                          * splice_dentry() gets called later. This is safe
1383                          * because no other place will use them */
1384                         req->r_dentry = req->r_old_dentry;
1385                         req->r_old_dentry = dn;
1386                         dn = req->r_dentry;
1387                 }
1388
1389                 /* null dentry? */
1390                 if (!rinfo->head->is_target) {
1391                         dout("fill_trace null dentry\n");
1392                         if (d_really_is_positive(dn)) {
1393                                 dout("d_delete %p\n", dn);
1394                                 ceph_dir_clear_ordered(dir);
1395                                 d_delete(dn);
1396                         } else if (have_lease) {
1397                                 if (d_unhashed(dn))
1398                                         d_add(dn, NULL);
1399                                 update_dentry_lease(dir, dn,
1400                                                     rinfo->dlease, session,
1401                                                     req->r_request_started);
1402                         }
1403                         goto done;
1404                 }
1405
1406                 /* attach proper inode */
1407                 if (d_really_is_negative(dn)) {
1408                         ceph_dir_clear_ordered(dir);
1409                         ihold(in);
1410                         err = splice_dentry(&req->r_dentry, in);
1411                         if (err < 0)
1412                                 goto done;
1413                         dn = req->r_dentry;  /* may have spliced */
1414                 } else if (d_really_is_positive(dn) && d_inode(dn) != in) {
1415                         dout(" %p links to %p %llx.%llx, not %llx.%llx\n",
1416                              dn, d_inode(dn), ceph_vinop(d_inode(dn)),
1417                              ceph_vinop(in));
1418                         d_invalidate(dn);
1419                         have_lease = false;
1420                 }
1421
1422                 if (have_lease) {
1423                         update_dentry_lease(dir, dn,
1424                                             rinfo->dlease, session,
1425                                             req->r_request_started);
1426                 }
1427                 dout(" final dn %p\n", dn);
1428         } else if ((req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
1429                     req->r_op == CEPH_MDS_OP_MKSNAP) &&
1430                    !test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags)) {
1431                 struct inode *dir = req->r_parent;
1432
1433                 /* fill out a snapdir LOOKUPSNAP dentry */
1434                 BUG_ON(!dir);
1435                 BUG_ON(ceph_snap(dir) != CEPH_SNAPDIR);
1436                 BUG_ON(!req->r_dentry);
1437                 dout(" linking snapped dir %p to dn %p\n", in, req->r_dentry);
1438                 ceph_dir_clear_ordered(dir);
1439                 ihold(in);
1440                 err = splice_dentry(&req->r_dentry, in);
1441                 if (err < 0)
1442                         goto done;
1443         } else if (rinfo->head->is_dentry && req->r_dentry) {
1444                 /* parent inode is not locked, be carefull */
1445                 struct ceph_vino *ptvino = NULL;
1446                 dvino.ino = le64_to_cpu(rinfo->diri.in->ino);
1447                 dvino.snap = le64_to_cpu(rinfo->diri.in->snapid);
1448                 if (rinfo->head->is_target) {
1449                         tvino.ino = le64_to_cpu(rinfo->targeti.in->ino);
1450                         tvino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
1451                         ptvino = &tvino;
1452                 }
1453                 update_dentry_lease_careful(req->r_dentry, rinfo->dlease,
1454                                             session, req->r_request_started,
1455                                             rinfo->dname, rinfo->dname_len,
1456                                             &dvino, ptvino);
1457         }
1458 done:
1459         dout("fill_trace done err=%d\n", err);
1460         return err;
1461 }
1462
1463 /*
1464  * Prepopulate our cache with readdir results, leases, etc.
1465  */
1466 static int readdir_prepopulate_inodes_only(struct ceph_mds_request *req,
1467                                            struct ceph_mds_session *session)
1468 {
1469         struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1470         int i, err = 0;
1471
1472         for (i = 0; i < rinfo->dir_nr; i++) {
1473                 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
1474                 struct ceph_vino vino;
1475                 struct inode *in;
1476                 int rc;
1477
1478                 vino.ino = le64_to_cpu(rde->inode.in->ino);
1479                 vino.snap = le64_to_cpu(rde->inode.in->snapid);
1480
1481                 in = ceph_get_inode(req->r_dentry->d_sb, vino);
1482                 if (IS_ERR(in)) {
1483                         err = PTR_ERR(in);
1484                         dout("new_inode badness got %d\n", err);
1485                         continue;
1486                 }
1487                 rc = fill_inode(in, NULL, &rde->inode, NULL, session,
1488                                 req->r_request_started, -1,
1489                                 &req->r_caps_reservation);
1490                 if (rc < 0) {
1491                         pr_err("fill_inode badness on %p got %d\n", in, rc);
1492                         err = rc;
1493                 }
1494                 /* avoid calling iput_final() in mds dispatch threads */
1495                 ceph_async_iput(in);
1496         }
1497
1498         return err;
1499 }
1500
1501 void ceph_readdir_cache_release(struct ceph_readdir_cache_control *ctl)
1502 {
1503         if (ctl->page) {
1504                 kunmap(ctl->page);
1505                 put_page(ctl->page);
1506                 ctl->page = NULL;
1507         }
1508 }
1509
1510 static int fill_readdir_cache(struct inode *dir, struct dentry *dn,
1511                               struct ceph_readdir_cache_control *ctl,
1512                               struct ceph_mds_request *req)
1513 {
1514         struct ceph_inode_info *ci = ceph_inode(dir);
1515         unsigned nsize = PAGE_SIZE / sizeof(struct dentry*);
1516         unsigned idx = ctl->index % nsize;
1517         pgoff_t pgoff = ctl->index / nsize;
1518
1519         if (!ctl->page || pgoff != page_index(ctl->page)) {
1520                 ceph_readdir_cache_release(ctl);
1521                 if (idx == 0)
1522                         ctl->page = grab_cache_page(&dir->i_data, pgoff);
1523                 else
1524                         ctl->page = find_lock_page(&dir->i_data, pgoff);
1525                 if (!ctl->page) {
1526                         ctl->index = -1;
1527                         return idx == 0 ? -ENOMEM : 0;
1528                 }
1529                 /* reading/filling the cache are serialized by
1530                  * i_mutex, no need to use page lock */
1531                 unlock_page(ctl->page);
1532                 ctl->dentries = kmap(ctl->page);
1533                 if (idx == 0)
1534                         memset(ctl->dentries, 0, PAGE_SIZE);
1535         }
1536
1537         if (req->r_dir_release_cnt == atomic64_read(&ci->i_release_count) &&
1538             req->r_dir_ordered_cnt == atomic64_read(&ci->i_ordered_count)) {
1539                 dout("readdir cache dn %p idx %d\n", dn, ctl->index);
1540                 ctl->dentries[idx] = dn;
1541                 ctl->index++;
1542         } else {
1543                 dout("disable readdir cache\n");
1544                 ctl->index = -1;
1545         }
1546         return 0;
1547 }
1548
1549 int ceph_readdir_prepopulate(struct ceph_mds_request *req,
1550                              struct ceph_mds_session *session)
1551 {
1552         struct dentry *parent = req->r_dentry;
1553         struct ceph_inode_info *ci = ceph_inode(d_inode(parent));
1554         struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
1555         struct qstr dname;
1556         struct dentry *dn;
1557         struct inode *in;
1558         int err = 0, skipped = 0, ret, i;
1559         struct ceph_mds_request_head *rhead = req->r_request->front.iov_base;
1560         u32 frag = le32_to_cpu(rhead->args.readdir.frag);
1561         u32 last_hash = 0;
1562         u32 fpos_offset;
1563         struct ceph_readdir_cache_control cache_ctl = {};
1564
1565         if (test_bit(CEPH_MDS_R_ABORTED, &req->r_req_flags))
1566                 return readdir_prepopulate_inodes_only(req, session);
1567
1568         if (rinfo->hash_order) {
1569                 if (req->r_path2) {
1570                         last_hash = ceph_str_hash(ci->i_dir_layout.dl_dir_hash,
1571                                                   req->r_path2,
1572                                                   strlen(req->r_path2));
1573                         last_hash = ceph_frag_value(last_hash);
1574                 } else if (rinfo->offset_hash) {
1575                         /* mds understands offset_hash */
1576                         WARN_ON_ONCE(req->r_readdir_offset != 2);
1577                         last_hash = le32_to_cpu(rhead->args.readdir.offset_hash);
1578                 }
1579         }
1580
1581         if (rinfo->dir_dir &&
1582             le32_to_cpu(rinfo->dir_dir->frag) != frag) {
1583                 dout("readdir_prepopulate got new frag %x -> %x\n",
1584                      frag, le32_to_cpu(rinfo->dir_dir->frag));
1585                 frag = le32_to_cpu(rinfo->dir_dir->frag);
1586                 if (!rinfo->hash_order)
1587                         req->r_readdir_offset = 2;
1588         }
1589
1590         if (le32_to_cpu(rinfo->head->op) == CEPH_MDS_OP_LSSNAP) {
1591                 dout("readdir_prepopulate %d items under SNAPDIR dn %p\n",
1592                      rinfo->dir_nr, parent);
1593         } else {
1594                 dout("readdir_prepopulate %d items under dn %p\n",
1595                      rinfo->dir_nr, parent);
1596                 if (rinfo->dir_dir)
1597                         ceph_fill_dirfrag(d_inode(parent), rinfo->dir_dir);
1598
1599                 if (ceph_frag_is_leftmost(frag) &&
1600                     req->r_readdir_offset == 2 &&
1601                     !(rinfo->hash_order && last_hash)) {
1602                         /* note dir version at start of readdir so we can
1603                          * tell if any dentries get dropped */
1604                         req->r_dir_release_cnt =
1605                                 atomic64_read(&ci->i_release_count);
1606                         req->r_dir_ordered_cnt =
1607                                 atomic64_read(&ci->i_ordered_count);
1608                         req->r_readdir_cache_idx = 0;
1609                 }
1610         }
1611
1612         cache_ctl.index = req->r_readdir_cache_idx;
1613         fpos_offset = req->r_readdir_offset;
1614
1615         /* FIXME: release caps/leases if error occurs */
1616         for (i = 0; i < rinfo->dir_nr; i++) {
1617                 struct ceph_mds_reply_dir_entry *rde = rinfo->dir_entries + i;
1618                 struct ceph_vino tvino;
1619
1620                 dname.name = rde->name;
1621                 dname.len = rde->name_len;
1622                 dname.hash = full_name_hash(parent, dname.name, dname.len);
1623
1624                 tvino.ino = le64_to_cpu(rde->inode.in->ino);
1625                 tvino.snap = le64_to_cpu(rde->inode.in->snapid);
1626
1627                 if (rinfo->hash_order) {
1628                         u32 hash = ceph_str_hash(ci->i_dir_layout.dl_dir_hash,
1629                                                  rde->name, rde->name_len);
1630                         hash = ceph_frag_value(hash);
1631                         if (hash != last_hash)
1632                                 fpos_offset = 2;
1633                         last_hash = hash;
1634                         rde->offset = ceph_make_fpos(hash, fpos_offset++, true);
1635                 } else {
1636                         rde->offset = ceph_make_fpos(frag, fpos_offset++, false);
1637                 }
1638
1639 retry_lookup:
1640                 dn = d_lookup(parent, &dname);
1641                 dout("d_lookup on parent=%p name=%.*s got %p\n",
1642                      parent, dname.len, dname.name, dn);
1643
1644                 if (!dn) {
1645                         dn = d_alloc(parent, &dname);
1646                         dout("d_alloc %p '%.*s' = %p\n", parent,
1647                              dname.len, dname.name, dn);
1648                         if (!dn) {
1649                                 dout("d_alloc badness\n");
1650                                 err = -ENOMEM;
1651                                 goto out;
1652                         }
1653                 } else if (d_really_is_positive(dn) &&
1654                            (ceph_ino(d_inode(dn)) != tvino.ino ||
1655                             ceph_snap(d_inode(dn)) != tvino.snap)) {
1656                         struct ceph_dentry_info *di = ceph_dentry(dn);
1657                         dout(" dn %p points to wrong inode %p\n",
1658                              dn, d_inode(dn));
1659
1660                         spin_lock(&dn->d_lock);
1661                         if (di->offset > 0 &&
1662                             di->lease_shared_gen ==
1663                             atomic_read(&ci->i_shared_gen)) {
1664                                 __ceph_dir_clear_ordered(ci);
1665                                 di->offset = 0;
1666                         }
1667                         spin_unlock(&dn->d_lock);
1668
1669                         d_delete(dn);
1670                         dput(dn);
1671                         goto retry_lookup;
1672                 }
1673
1674                 /* inode */
1675                 if (d_really_is_positive(dn)) {
1676                         in = d_inode(dn);
1677                 } else {
1678                         in = ceph_get_inode(parent->d_sb, tvino);
1679                         if (IS_ERR(in)) {
1680                                 dout("new_inode badness\n");
1681                                 d_drop(dn);
1682                                 dput(dn);
1683                                 err = PTR_ERR(in);
1684                                 goto out;
1685                         }
1686                 }
1687
1688                 ret = fill_inode(in, NULL, &rde->inode, NULL, session,
1689                                  req->r_request_started, -1,
1690                                  &req->r_caps_reservation);
1691                 if (ret < 0) {
1692                         pr_err("fill_inode badness on %p\n", in);
1693                         if (d_really_is_negative(dn)) {
1694                                 /* avoid calling iput_final() in mds
1695                                  * dispatch threads */
1696                                 ceph_async_iput(in);
1697                         }
1698                         d_drop(dn);
1699                         err = ret;
1700                         goto next_item;
1701                 }
1702
1703                 if (d_really_is_negative(dn)) {
1704                         if (ceph_security_xattr_deadlock(in)) {
1705                                 dout(" skip splicing dn %p to inode %p"
1706                                      " (security xattr deadlock)\n", dn, in);
1707                                 ceph_async_iput(in);
1708                                 skipped++;
1709                                 goto next_item;
1710                         }
1711
1712                         err = splice_dentry(&dn, in);
1713                         if (err < 0)
1714                                 goto next_item;
1715                 }
1716
1717                 ceph_dentry(dn)->offset = rde->offset;
1718
1719                 update_dentry_lease(d_inode(parent), dn,
1720                                     rde->lease, req->r_session,
1721                                     req->r_request_started);
1722
1723                 if (err == 0 && skipped == 0 && cache_ctl.index >= 0) {
1724                         ret = fill_readdir_cache(d_inode(parent), dn,
1725                                                  &cache_ctl, req);
1726                         if (ret < 0)
1727                                 err = ret;
1728                 }
1729 next_item:
1730                 dput(dn);
1731         }
1732 out:
1733         if (err == 0 && skipped == 0) {
1734                 set_bit(CEPH_MDS_R_DID_PREPOPULATE, &req->r_req_flags);
1735                 req->r_readdir_cache_idx = cache_ctl.index;
1736         }
1737         ceph_readdir_cache_release(&cache_ctl);
1738         dout("readdir_prepopulate done\n");
1739         return err;
1740 }
1741
1742 bool ceph_inode_set_size(struct inode *inode, loff_t size)
1743 {
1744         struct ceph_inode_info *ci = ceph_inode(inode);
1745         bool ret;
1746
1747         spin_lock(&ci->i_ceph_lock);
1748         dout("set_size %p %llu -> %llu\n", inode, inode->i_size, size);
1749         i_size_write(inode, size);
1750         inode->i_blocks = calc_inode_blocks(size);
1751
1752         ret = __ceph_should_report_size(ci);
1753
1754         spin_unlock(&ci->i_ceph_lock);
1755         return ret;
1756 }
1757
1758 /*
1759  * Put reference to inode, but avoid calling iput_final() in current thread.
1760  * iput_final() may wait for reahahead pages. The wait can cause deadlock in
1761  * some contexts.
1762  */
1763 void ceph_async_iput(struct inode *inode)
1764 {
1765         if (!inode)
1766                 return;
1767         for (;;) {
1768                 if (atomic_add_unless(&inode->i_count, -1, 1))
1769                         break;
1770                 if (queue_work(ceph_inode_to_client(inode)->inode_wq,
1771                                &ceph_inode(inode)->i_work))
1772                         break;
1773                 /* queue work failed, i_count must be at least 2 */
1774         }
1775 }
1776
1777 /*
1778  * Write back inode data in a worker thread.  (This can't be done
1779  * in the message handler context.)
1780  */
1781 void ceph_queue_writeback(struct inode *inode)
1782 {
1783         struct ceph_inode_info *ci = ceph_inode(inode);
1784         set_bit(CEPH_I_WORK_WRITEBACK, &ci->i_work_mask);
1785
1786         ihold(inode);
1787         if (queue_work(ceph_inode_to_client(inode)->inode_wq,
1788                        &ci->i_work)) {
1789                 dout("ceph_queue_writeback %p\n", inode);
1790         } else {
1791                 dout("ceph_queue_writeback %p already queued, mask=%lx\n",
1792                      inode, ci->i_work_mask);
1793                 iput(inode);
1794         }
1795 }
1796
1797 /*
1798  * queue an async invalidation
1799  */
1800 void ceph_queue_invalidate(struct inode *inode)
1801 {
1802         struct ceph_inode_info *ci = ceph_inode(inode);
1803         set_bit(CEPH_I_WORK_INVALIDATE_PAGES, &ci->i_work_mask);
1804
1805         ihold(inode);
1806         if (queue_work(ceph_inode_to_client(inode)->inode_wq,
1807                        &ceph_inode(inode)->i_work)) {
1808                 dout("ceph_queue_invalidate %p\n", inode);
1809         } else {
1810                 dout("ceph_queue_invalidate %p already queued, mask=%lx\n",
1811                      inode, ci->i_work_mask);
1812                 iput(inode);
1813         }
1814 }
1815
1816 /*
1817  * Queue an async vmtruncate.  If we fail to queue work, we will handle
1818  * the truncation the next time we call __ceph_do_pending_vmtruncate.
1819  */
1820 void ceph_queue_vmtruncate(struct inode *inode)
1821 {
1822         struct ceph_inode_info *ci = ceph_inode(inode);
1823         set_bit(CEPH_I_WORK_VMTRUNCATE, &ci->i_work_mask);
1824
1825         ihold(inode);
1826         if (queue_work(ceph_inode_to_client(inode)->inode_wq,
1827                        &ci->i_work)) {
1828                 dout("ceph_queue_vmtruncate %p\n", inode);
1829         } else {
1830                 dout("ceph_queue_vmtruncate %p already queued, mask=%lx\n",
1831                      inode, ci->i_work_mask);
1832                 iput(inode);
1833         }
1834 }
1835
1836 static void ceph_do_invalidate_pages(struct inode *inode)
1837 {
1838         struct ceph_inode_info *ci = ceph_inode(inode);
1839         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
1840         u32 orig_gen;
1841         int check = 0;
1842
1843         mutex_lock(&ci->i_truncate_mutex);
1844
1845         if (READ_ONCE(fsc->mount_state) == CEPH_MOUNT_SHUTDOWN) {
1846                 pr_warn_ratelimited("invalidate_pages %p %lld forced umount\n",
1847                                     inode, ceph_ino(inode));
1848                 mapping_set_error(inode->i_mapping, -EIO);
1849                 truncate_pagecache(inode, 0);
1850                 mutex_unlock(&ci->i_truncate_mutex);
1851                 goto out;
1852         }
1853
1854         spin_lock(&ci->i_ceph_lock);
1855         dout("invalidate_pages %p gen %d revoking %d\n", inode,
1856              ci->i_rdcache_gen, ci->i_rdcache_revoking);
1857         if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
1858                 if (__ceph_caps_revoking_other(ci, NULL, CEPH_CAP_FILE_CACHE))
1859                         check = 1;
1860                 spin_unlock(&ci->i_ceph_lock);
1861                 mutex_unlock(&ci->i_truncate_mutex);
1862                 goto out;
1863         }
1864         orig_gen = ci->i_rdcache_gen;
1865         spin_unlock(&ci->i_ceph_lock);
1866
1867         if (invalidate_inode_pages2(inode->i_mapping) < 0) {
1868                 pr_err("invalidate_pages %p fails\n", inode);
1869         }
1870
1871         spin_lock(&ci->i_ceph_lock);
1872         if (orig_gen == ci->i_rdcache_gen &&
1873             orig_gen == ci->i_rdcache_revoking) {
1874                 dout("invalidate_pages %p gen %d successful\n", inode,
1875                      ci->i_rdcache_gen);
1876                 ci->i_rdcache_revoking--;
1877                 check = 1;
1878         } else {
1879                 dout("invalidate_pages %p gen %d raced, now %d revoking %d\n",
1880                      inode, orig_gen, ci->i_rdcache_gen,
1881                      ci->i_rdcache_revoking);
1882                 if (__ceph_caps_revoking_other(ci, NULL, CEPH_CAP_FILE_CACHE))
1883                         check = 1;
1884         }
1885         spin_unlock(&ci->i_ceph_lock);
1886         mutex_unlock(&ci->i_truncate_mutex);
1887 out:
1888         if (check)
1889                 ceph_check_caps(ci, 0, NULL);
1890 }
1891
1892 /*
1893  * Make sure any pending truncation is applied before doing anything
1894  * that may depend on it.
1895  */
1896 void __ceph_do_pending_vmtruncate(struct inode *inode)
1897 {
1898         struct ceph_inode_info *ci = ceph_inode(inode);
1899         u64 to;
1900         int wrbuffer_refs, finish = 0;
1901
1902         mutex_lock(&ci->i_truncate_mutex);
1903 retry:
1904         spin_lock(&ci->i_ceph_lock);
1905         if (ci->i_truncate_pending == 0) {
1906                 dout("__do_pending_vmtruncate %p none pending\n", inode);
1907                 spin_unlock(&ci->i_ceph_lock);
1908                 mutex_unlock(&ci->i_truncate_mutex);
1909                 return;
1910         }
1911
1912         /*
1913          * make sure any dirty snapped pages are flushed before we
1914          * possibly truncate them.. so write AND block!
1915          */
1916         if (ci->i_wrbuffer_ref_head < ci->i_wrbuffer_ref) {
1917                 spin_unlock(&ci->i_ceph_lock);
1918                 dout("__do_pending_vmtruncate %p flushing snaps first\n",
1919                      inode);
1920                 filemap_write_and_wait_range(&inode->i_data, 0,
1921                                              inode->i_sb->s_maxbytes);
1922                 goto retry;
1923         }
1924
1925         /* there should be no reader or writer */
1926         WARN_ON_ONCE(ci->i_rd_ref || ci->i_wr_ref);
1927
1928         to = ci->i_truncate_size;
1929         wrbuffer_refs = ci->i_wrbuffer_ref;
1930         dout("__do_pending_vmtruncate %p (%d) to %lld\n", inode,
1931              ci->i_truncate_pending, to);
1932         spin_unlock(&ci->i_ceph_lock);
1933
1934         truncate_pagecache(inode, to);
1935
1936         spin_lock(&ci->i_ceph_lock);
1937         if (to == ci->i_truncate_size) {
1938                 ci->i_truncate_pending = 0;
1939                 finish = 1;
1940         }
1941         spin_unlock(&ci->i_ceph_lock);
1942         if (!finish)
1943                 goto retry;
1944
1945         mutex_unlock(&ci->i_truncate_mutex);
1946
1947         if (wrbuffer_refs == 0)
1948                 ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
1949
1950         wake_up_all(&ci->i_cap_wq);
1951 }
1952
1953 static void ceph_inode_work(struct work_struct *work)
1954 {
1955         struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
1956                                                  i_work);
1957         struct inode *inode = &ci->vfs_inode;
1958
1959         if (test_and_clear_bit(CEPH_I_WORK_WRITEBACK, &ci->i_work_mask)) {
1960                 dout("writeback %p\n", inode);
1961                 filemap_fdatawrite(&inode->i_data);
1962         }
1963         if (test_and_clear_bit(CEPH_I_WORK_INVALIDATE_PAGES, &ci->i_work_mask))
1964                 ceph_do_invalidate_pages(inode);
1965
1966         if (test_and_clear_bit(CEPH_I_WORK_VMTRUNCATE, &ci->i_work_mask))
1967                 __ceph_do_pending_vmtruncate(inode);
1968
1969         iput(inode);
1970 }
1971
1972 /*
1973  * symlinks
1974  */
1975 static const struct inode_operations ceph_symlink_iops = {
1976         .get_link = simple_get_link,
1977         .setattr = ceph_setattr,
1978         .getattr = ceph_getattr,
1979         .listxattr = ceph_listxattr,
1980 };
1981
1982 int __ceph_setattr(struct inode *inode, struct iattr *attr)
1983 {
1984         struct ceph_inode_info *ci = ceph_inode(inode);
1985         const unsigned int ia_valid = attr->ia_valid;
1986         struct ceph_mds_request *req;
1987         struct ceph_mds_client *mdsc = ceph_sb_to_client(inode->i_sb)->mdsc;
1988         struct ceph_cap_flush *prealloc_cf;
1989         int issued;
1990         int release = 0, dirtied = 0;
1991         int mask = 0;
1992         int err = 0;
1993         int inode_dirty_flags = 0;
1994         bool lock_snap_rwsem = false;
1995
1996         prealloc_cf = ceph_alloc_cap_flush();
1997         if (!prealloc_cf)
1998                 return -ENOMEM;
1999
2000         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETATTR,
2001                                        USE_AUTH_MDS);
2002         if (IS_ERR(req)) {
2003                 ceph_free_cap_flush(prealloc_cf);
2004                 return PTR_ERR(req);
2005         }
2006
2007         spin_lock(&ci->i_ceph_lock);
2008         issued = __ceph_caps_issued(ci, NULL);
2009
2010         if (!ci->i_head_snapc &&
2011             (issued & (CEPH_CAP_ANY_EXCL | CEPH_CAP_FILE_WR))) {
2012                 lock_snap_rwsem = true;
2013                 if (!down_read_trylock(&mdsc->snap_rwsem)) {
2014                         spin_unlock(&ci->i_ceph_lock);
2015                         down_read(&mdsc->snap_rwsem);
2016                         spin_lock(&ci->i_ceph_lock);
2017                         issued = __ceph_caps_issued(ci, NULL);
2018                 }
2019         }
2020
2021         dout("setattr %p issued %s\n", inode, ceph_cap_string(issued));
2022
2023         if (ia_valid & ATTR_UID) {
2024                 dout("setattr %p uid %d -> %d\n", inode,
2025                      from_kuid(&init_user_ns, inode->i_uid),
2026                      from_kuid(&init_user_ns, attr->ia_uid));
2027                 if (issued & CEPH_CAP_AUTH_EXCL) {
2028                         inode->i_uid = attr->ia_uid;
2029                         dirtied |= CEPH_CAP_AUTH_EXCL;
2030                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
2031                            !uid_eq(attr->ia_uid, inode->i_uid)) {
2032                         req->r_args.setattr.uid = cpu_to_le32(
2033                                 from_kuid(&init_user_ns, attr->ia_uid));
2034                         mask |= CEPH_SETATTR_UID;
2035                         release |= CEPH_CAP_AUTH_SHARED;
2036                 }
2037         }
2038         if (ia_valid & ATTR_GID) {
2039                 dout("setattr %p gid %d -> %d\n", inode,
2040                      from_kgid(&init_user_ns, inode->i_gid),
2041                      from_kgid(&init_user_ns, attr->ia_gid));
2042                 if (issued & CEPH_CAP_AUTH_EXCL) {
2043                         inode->i_gid = attr->ia_gid;
2044                         dirtied |= CEPH_CAP_AUTH_EXCL;
2045                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
2046                            !gid_eq(attr->ia_gid, inode->i_gid)) {
2047                         req->r_args.setattr.gid = cpu_to_le32(
2048                                 from_kgid(&init_user_ns, attr->ia_gid));
2049                         mask |= CEPH_SETATTR_GID;
2050                         release |= CEPH_CAP_AUTH_SHARED;
2051                 }
2052         }
2053         if (ia_valid & ATTR_MODE) {
2054                 dout("setattr %p mode 0%o -> 0%o\n", inode, inode->i_mode,
2055                      attr->ia_mode);
2056                 if (issued & CEPH_CAP_AUTH_EXCL) {
2057                         inode->i_mode = attr->ia_mode;
2058                         dirtied |= CEPH_CAP_AUTH_EXCL;
2059                 } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
2060                            attr->ia_mode != inode->i_mode) {
2061                         inode->i_mode = attr->ia_mode;
2062                         req->r_args.setattr.mode = cpu_to_le32(attr->ia_mode);
2063                         mask |= CEPH_SETATTR_MODE;
2064                         release |= CEPH_CAP_AUTH_SHARED;
2065                 }
2066         }
2067
2068         if (ia_valid & ATTR_ATIME) {
2069                 dout("setattr %p atime %lld.%ld -> %lld.%ld\n", inode,
2070                      inode->i_atime.tv_sec, inode->i_atime.tv_nsec,
2071                      attr->ia_atime.tv_sec, attr->ia_atime.tv_nsec);
2072                 if (issued & CEPH_CAP_FILE_EXCL) {
2073                         ci->i_time_warp_seq++;
2074                         inode->i_atime = attr->ia_atime;
2075                         dirtied |= CEPH_CAP_FILE_EXCL;
2076                 } else if ((issued & CEPH_CAP_FILE_WR) &&
2077                            timespec64_compare(&inode->i_atime,
2078                                             &attr->ia_atime) < 0) {
2079                         inode->i_atime = attr->ia_atime;
2080                         dirtied |= CEPH_CAP_FILE_WR;
2081                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
2082                            !timespec64_equal(&inode->i_atime, &attr->ia_atime)) {
2083                         ceph_encode_timespec64(&req->r_args.setattr.atime,
2084                                                &attr->ia_atime);
2085                         mask |= CEPH_SETATTR_ATIME;
2086                         release |= CEPH_CAP_FILE_SHARED |
2087                                    CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
2088                 }
2089         }
2090         if (ia_valid & ATTR_MTIME) {
2091                 dout("setattr %p mtime %lld.%ld -> %lld.%ld\n", inode,
2092                      inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
2093                      attr->ia_mtime.tv_sec, attr->ia_mtime.tv_nsec);
2094                 if (issued & CEPH_CAP_FILE_EXCL) {
2095                         ci->i_time_warp_seq++;
2096                         inode->i_mtime = attr->ia_mtime;
2097                         dirtied |= CEPH_CAP_FILE_EXCL;
2098                 } else if ((issued & CEPH_CAP_FILE_WR) &&
2099                            timespec64_compare(&inode->i_mtime,
2100                                             &attr->ia_mtime) < 0) {
2101                         inode->i_mtime = attr->ia_mtime;
2102                         dirtied |= CEPH_CAP_FILE_WR;
2103                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
2104                            !timespec64_equal(&inode->i_mtime, &attr->ia_mtime)) {
2105                         ceph_encode_timespec64(&req->r_args.setattr.mtime,
2106                                                &attr->ia_mtime);
2107                         mask |= CEPH_SETATTR_MTIME;
2108                         release |= CEPH_CAP_FILE_SHARED |
2109                                    CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
2110                 }
2111         }
2112         if (ia_valid & ATTR_SIZE) {
2113                 dout("setattr %p size %lld -> %lld\n", inode,
2114                      inode->i_size, attr->ia_size);
2115                 if ((issued & CEPH_CAP_FILE_EXCL) &&
2116                     attr->ia_size > inode->i_size) {
2117                         i_size_write(inode, attr->ia_size);
2118                         inode->i_blocks = calc_inode_blocks(attr->ia_size);
2119                         ci->i_reported_size = attr->ia_size;
2120                         dirtied |= CEPH_CAP_FILE_EXCL;
2121                 } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
2122                            attr->ia_size != inode->i_size) {
2123                         req->r_args.setattr.size = cpu_to_le64(attr->ia_size);
2124                         req->r_args.setattr.old_size =
2125                                 cpu_to_le64(inode->i_size);
2126                         mask |= CEPH_SETATTR_SIZE;
2127                         release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_EXCL |
2128                                    CEPH_CAP_FILE_RD | CEPH_CAP_FILE_WR;
2129                 }
2130         }
2131
2132         /* these do nothing */
2133         if (ia_valid & ATTR_CTIME) {
2134                 bool only = (ia_valid & (ATTR_SIZE|ATTR_MTIME|ATTR_ATIME|
2135                                          ATTR_MODE|ATTR_UID|ATTR_GID)) == 0;
2136                 dout("setattr %p ctime %lld.%ld -> %lld.%ld (%s)\n", inode,
2137                      inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
2138                      attr->ia_ctime.tv_sec, attr->ia_ctime.tv_nsec,
2139                      only ? "ctime only" : "ignored");
2140                 if (only) {
2141                         /*
2142                          * if kernel wants to dirty ctime but nothing else,
2143                          * we need to choose a cap to dirty under, or do
2144                          * a almost-no-op setattr
2145                          */
2146                         if (issued & CEPH_CAP_AUTH_EXCL)
2147                                 dirtied |= CEPH_CAP_AUTH_EXCL;
2148                         else if (issued & CEPH_CAP_FILE_EXCL)
2149                                 dirtied |= CEPH_CAP_FILE_EXCL;
2150                         else if (issued & CEPH_CAP_XATTR_EXCL)
2151                                 dirtied |= CEPH_CAP_XATTR_EXCL;
2152                         else
2153                                 mask |= CEPH_SETATTR_CTIME;
2154                 }
2155         }
2156         if (ia_valid & ATTR_FILE)
2157                 dout("setattr %p ATTR_FILE ... hrm!\n", inode);
2158
2159         if (dirtied) {
2160                 inode_dirty_flags = __ceph_mark_dirty_caps(ci, dirtied,
2161                                                            &prealloc_cf);
2162                 inode->i_ctime = attr->ia_ctime;
2163         }
2164
2165         release &= issued;
2166         spin_unlock(&ci->i_ceph_lock);
2167         if (lock_snap_rwsem)
2168                 up_read(&mdsc->snap_rwsem);
2169
2170         if (inode_dirty_flags)
2171                 __mark_inode_dirty(inode, inode_dirty_flags);
2172
2173
2174         if (mask) {
2175                 req->r_inode = inode;
2176                 ihold(inode);
2177                 req->r_inode_drop = release;
2178                 req->r_args.setattr.mask = cpu_to_le32(mask);
2179                 req->r_num_caps = 1;
2180                 req->r_stamp = attr->ia_ctime;
2181                 err = ceph_mdsc_do_request(mdsc, NULL, req);
2182         }
2183         dout("setattr %p result=%d (%s locally, %d remote)\n", inode, err,
2184              ceph_cap_string(dirtied), mask);
2185
2186         ceph_mdsc_put_request(req);
2187         ceph_free_cap_flush(prealloc_cf);
2188
2189         if (err >= 0 && (mask & CEPH_SETATTR_SIZE))
2190                 __ceph_do_pending_vmtruncate(inode);
2191
2192         return err;
2193 }
2194
2195 /*
2196  * setattr
2197  */
2198 int ceph_setattr(struct dentry *dentry, struct iattr *attr)
2199 {
2200         struct inode *inode = d_inode(dentry);
2201         struct ceph_fs_client *fsc = ceph_inode_to_client(inode);
2202         int err;
2203
2204         if (ceph_snap(inode) != CEPH_NOSNAP)
2205                 return -EROFS;
2206
2207         err = setattr_prepare(dentry, attr);
2208         if (err != 0)
2209                 return err;
2210
2211         if ((attr->ia_valid & ATTR_SIZE) &&
2212             attr->ia_size > max(inode->i_size, fsc->max_file_size))
2213                 return -EFBIG;
2214
2215         if ((attr->ia_valid & ATTR_SIZE) &&
2216             ceph_quota_is_max_bytes_exceeded(inode, attr->ia_size))
2217                 return -EDQUOT;
2218
2219         err = __ceph_setattr(inode, attr);
2220
2221         if (err >= 0 && (attr->ia_valid & ATTR_MODE))
2222                 err = posix_acl_chmod(inode, attr->ia_mode);
2223
2224         return err;
2225 }
2226
2227 /*
2228  * Verify that we have a lease on the given mask.  If not,
2229  * do a getattr against an mds.
2230  */
2231 int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
2232                       int mask, bool force)
2233 {
2234         struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
2235         struct ceph_mds_client *mdsc = fsc->mdsc;
2236         struct ceph_mds_request *req;
2237         int mode;
2238         int err;
2239
2240         if (ceph_snap(inode) == CEPH_SNAPDIR) {
2241                 dout("do_getattr inode %p SNAPDIR\n", inode);
2242                 return 0;
2243         }
2244
2245         dout("do_getattr inode %p mask %s mode 0%o\n",
2246              inode, ceph_cap_string(mask), inode->i_mode);
2247         if (!force && ceph_caps_issued_mask(ceph_inode(inode), mask, 1))
2248                 return 0;
2249
2250         mode = (mask & CEPH_STAT_RSTAT) ? USE_AUTH_MDS : USE_ANY_MDS;
2251         req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, mode);
2252         if (IS_ERR(req))
2253                 return PTR_ERR(req);
2254         req->r_inode = inode;
2255         ihold(inode);
2256         req->r_num_caps = 1;
2257         req->r_args.getattr.mask = cpu_to_le32(mask);
2258         req->r_locked_page = locked_page;
2259         err = ceph_mdsc_do_request(mdsc, NULL, req);
2260         if (locked_page && err == 0) {
2261                 u64 inline_version = req->r_reply_info.targeti.inline_version;
2262                 if (inline_version == 0) {
2263                         /* the reply is supposed to contain inline data */
2264                         err = -EINVAL;
2265                 } else if (inline_version == CEPH_INLINE_NONE) {
2266                         err = -ENODATA;
2267                 } else {
2268                         err = req->r_reply_info.targeti.inline_len;
2269                 }
2270         }
2271         ceph_mdsc_put_request(req);
2272         dout("do_getattr result=%d\n", err);
2273         return err;
2274 }
2275
2276
2277 /*
2278  * Check inode permissions.  We verify we have a valid value for
2279  * the AUTH cap, then call the generic handler.
2280  */
2281 int ceph_permission(struct inode *inode, int mask)
2282 {
2283         int err;
2284
2285         if (mask & MAY_NOT_BLOCK)
2286                 return -ECHILD;
2287
2288         err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
2289
2290         if (!err)
2291                 err = generic_permission(inode, mask);
2292         return err;
2293 }
2294
2295 /* Craft a mask of needed caps given a set of requested statx attrs. */
2296 static int statx_to_caps(u32 want)
2297 {
2298         int mask = 0;
2299
2300         if (want & (STATX_MODE|STATX_UID|STATX_GID|STATX_CTIME|STATX_BTIME))
2301                 mask |= CEPH_CAP_AUTH_SHARED;
2302
2303         if (want & (STATX_NLINK|STATX_CTIME))
2304                 mask |= CEPH_CAP_LINK_SHARED;
2305
2306         if (want & (STATX_ATIME|STATX_MTIME|STATX_CTIME|STATX_SIZE|
2307                     STATX_BLOCKS))
2308                 mask |= CEPH_CAP_FILE_SHARED;
2309
2310         if (want & (STATX_CTIME))
2311                 mask |= CEPH_CAP_XATTR_SHARED;
2312
2313         return mask;
2314 }
2315
2316 /*
2317  * Get all the attributes. If we have sufficient caps for the requested attrs,
2318  * then we can avoid talking to the MDS at all.
2319  */
2320 int ceph_getattr(const struct path *path, struct kstat *stat,
2321                  u32 request_mask, unsigned int flags)
2322 {
2323         struct inode *inode = d_inode(path->dentry);
2324         struct ceph_inode_info *ci = ceph_inode(inode);
2325         u32 valid_mask = STATX_BASIC_STATS;
2326         int err = 0;
2327
2328         /* Skip the getattr altogether if we're asked not to sync */
2329         if (!(flags & AT_STATX_DONT_SYNC)) {
2330                 err = ceph_do_getattr(inode, statx_to_caps(request_mask),
2331                                       flags & AT_STATX_FORCE_SYNC);
2332                 if (err)
2333                         return err;
2334         }
2335
2336         generic_fillattr(inode, stat);
2337         stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino);
2338
2339         /*
2340          * btime on newly-allocated inodes is 0, so if this is still set to
2341          * that, then assume that it's not valid.
2342          */
2343         if (ci->i_btime.tv_sec || ci->i_btime.tv_nsec) {
2344                 stat->btime = ci->i_btime;
2345                 valid_mask |= STATX_BTIME;
2346         }
2347
2348         if (ceph_snap(inode) == CEPH_NOSNAP)
2349                 stat->dev = inode->i_sb->s_dev;
2350         else
2351                 stat->dev = ci->i_snapid_map ? ci->i_snapid_map->dev : 0;
2352
2353         if (S_ISDIR(inode->i_mode)) {
2354                 if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb),
2355                                         RBYTES))
2356                         stat->size = ci->i_rbytes;
2357                 else
2358                         stat->size = ci->i_files + ci->i_subdirs;
2359                 stat->blocks = 0;
2360                 stat->blksize = 65536;
2361                 /*
2362                  * Some applications rely on the number of st_nlink
2363                  * value on directories to be either 0 (if unlinked)
2364                  * or 2 + number of subdirectories.
2365                  */
2366                 if (stat->nlink == 1)
2367                         /* '.' + '..' + subdirs */
2368                         stat->nlink = 1 + 1 + ci->i_subdirs;
2369         }
2370
2371         stat->result_mask = request_mask & valid_mask;
2372         return err;
2373 }