Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / fs / ceph / inode.c
diff --git a/kernel/fs/ceph/inode.c b/kernel/fs/ceph/inode.c
new file mode 100644 (file)
index 0000000..e876e19
--- /dev/null
@@ -0,0 +1,2016 @@
+#include <linux/ceph/ceph_debug.h>
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/uaccess.h>
+#include <linux/kernel.h>
+#include <linux/namei.h>
+#include <linux/writeback.h>
+#include <linux/vmalloc.h>
+#include <linux/posix_acl.h>
+#include <linux/random.h>
+
+#include "super.h"
+#include "mds_client.h"
+#include "cache.h"
+#include <linux/ceph/decode.h>
+
+/*
+ * Ceph inode operations
+ *
+ * Implement basic inode helpers (get, alloc) and inode ops (getattr,
+ * setattr, etc.), xattr helpers, and helpers for assimilating
+ * metadata returned by the MDS into our cache.
+ *
+ * Also define helpers for doing asynchronous writeback, invalidation,
+ * and truncation for the benefit of those who can't afford to block
+ * (typically because they are in the message handler path).
+ */
+
+static const struct inode_operations ceph_symlink_iops;
+
+static void ceph_invalidate_work(struct work_struct *work);
+static void ceph_writeback_work(struct work_struct *work);
+static void ceph_vmtruncate_work(struct work_struct *work);
+
+/*
+ * find or create an inode, given the ceph ino number
+ */
+static int ceph_set_ino_cb(struct inode *inode, void *data)
+{
+       ceph_inode(inode)->i_vino = *(struct ceph_vino *)data;
+       inode->i_ino = ceph_vino_to_ino(*(struct ceph_vino *)data);
+       return 0;
+}
+
+struct inode *ceph_get_inode(struct super_block *sb, struct ceph_vino vino)
+{
+       struct inode *inode;
+       ino_t t = ceph_vino_to_ino(vino);
+
+       inode = iget5_locked(sb, t, ceph_ino_compare, ceph_set_ino_cb, &vino);
+       if (inode == NULL)
+               return ERR_PTR(-ENOMEM);
+       if (inode->i_state & I_NEW) {
+               dout("get_inode created new inode %p %llx.%llx ino %llx\n",
+                    inode, ceph_vinop(inode), (u64)inode->i_ino);
+               unlock_new_inode(inode);
+       }
+
+       dout("get_inode on %lu=%llx.%llx got %p\n", inode->i_ino, vino.ino,
+            vino.snap, inode);
+       return inode;
+}
+
+/*
+ * get/constuct snapdir inode for a given directory
+ */
+struct inode *ceph_get_snapdir(struct inode *parent)
+{
+       struct ceph_vino vino = {
+               .ino = ceph_ino(parent),
+               .snap = CEPH_SNAPDIR,
+       };
+       struct inode *inode = ceph_get_inode(parent->i_sb, vino);
+       struct ceph_inode_info *ci = ceph_inode(inode);
+
+       BUG_ON(!S_ISDIR(parent->i_mode));
+       if (IS_ERR(inode))
+               return inode;
+       inode->i_mode = parent->i_mode;
+       inode->i_uid = parent->i_uid;
+       inode->i_gid = parent->i_gid;
+       inode->i_op = &ceph_snapdir_iops;
+       inode->i_fop = &ceph_snapdir_fops;
+       ci->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
+       ci->i_rbytes = 0;
+       return inode;
+}
+
+const struct inode_operations ceph_file_iops = {
+       .permission = ceph_permission,
+       .setattr = ceph_setattr,
+       .getattr = ceph_getattr,
+       .setxattr = ceph_setxattr,
+       .getxattr = ceph_getxattr,
+       .listxattr = ceph_listxattr,
+       .removexattr = ceph_removexattr,
+       .get_acl = ceph_get_acl,
+       .set_acl = ceph_set_acl,
+};
+
+
+/*
+ * We use a 'frag tree' to keep track of the MDS's directory fragments
+ * for a given inode (usually there is just a single fragment).  We
+ * need to know when a child frag is delegated to a new MDS, or when
+ * it is flagged as replicated, so we can direct our requests
+ * accordingly.
+ */
+
+/*
+ * find/create a frag in the tree
+ */
+static struct ceph_inode_frag *__get_or_create_frag(struct ceph_inode_info *ci,
+                                                   u32 f)
+{
+       struct rb_node **p;
+       struct rb_node *parent = NULL;
+       struct ceph_inode_frag *frag;
+       int c;
+
+       p = &ci->i_fragtree.rb_node;
+       while (*p) {
+               parent = *p;
+               frag = rb_entry(parent, struct ceph_inode_frag, node);
+               c = ceph_frag_compare(f, frag->frag);
+               if (c < 0)
+                       p = &(*p)->rb_left;
+               else if (c > 0)
+                       p = &(*p)->rb_right;
+               else
+                       return frag;
+       }
+
+       frag = kmalloc(sizeof(*frag), GFP_NOFS);
+       if (!frag) {
+               pr_err("__get_or_create_frag ENOMEM on %p %llx.%llx "
+                      "frag %x\n", &ci->vfs_inode,
+                      ceph_vinop(&ci->vfs_inode), f);
+               return ERR_PTR(-ENOMEM);
+       }
+       frag->frag = f;
+       frag->split_by = 0;
+       frag->mds = -1;
+       frag->ndist = 0;
+
+       rb_link_node(&frag->node, parent, p);
+       rb_insert_color(&frag->node, &ci->i_fragtree);
+
+       dout("get_or_create_frag added %llx.%llx frag %x\n",
+            ceph_vinop(&ci->vfs_inode), f);
+       return frag;
+}
+
+/*
+ * find a specific frag @f
+ */
+struct ceph_inode_frag *__ceph_find_frag(struct ceph_inode_info *ci, u32 f)
+{
+       struct rb_node *n = ci->i_fragtree.rb_node;
+
+       while (n) {
+               struct ceph_inode_frag *frag =
+                       rb_entry(n, struct ceph_inode_frag, node);
+               int c = ceph_frag_compare(f, frag->frag);
+               if (c < 0)
+                       n = n->rb_left;
+               else if (c > 0)
+                       n = n->rb_right;
+               else
+                       return frag;
+       }
+       return NULL;
+}
+
+/*
+ * Choose frag containing the given value @v.  If @pfrag is
+ * specified, copy the frag delegation info to the caller if
+ * it is present.
+ */
+static u32 __ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
+                             struct ceph_inode_frag *pfrag, int *found)
+{
+       u32 t = ceph_frag_make(0, 0);
+       struct ceph_inode_frag *frag;
+       unsigned nway, i;
+       u32 n;
+
+       if (found)
+               *found = 0;
+
+       while (1) {
+               WARN_ON(!ceph_frag_contains_value(t, v));
+               frag = __ceph_find_frag(ci, t);
+               if (!frag)
+                       break; /* t is a leaf */
+               if (frag->split_by == 0) {
+                       if (pfrag)
+                               memcpy(pfrag, frag, sizeof(*pfrag));
+                       if (found)
+                               *found = 1;
+                       break;
+               }
+
+               /* choose child */
+               nway = 1 << frag->split_by;
+               dout("choose_frag(%x) %x splits by %d (%d ways)\n", v, t,
+                    frag->split_by, nway);
+               for (i = 0; i < nway; i++) {
+                       n = ceph_frag_make_child(t, frag->split_by, i);
+                       if (ceph_frag_contains_value(n, v)) {
+                               t = n;
+                               break;
+                       }
+               }
+               BUG_ON(i == nway);
+       }
+       dout("choose_frag(%x) = %x\n", v, t);
+
+       return t;
+}
+
+u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
+                    struct ceph_inode_frag *pfrag, int *found)
+{
+       u32 ret;
+       mutex_lock(&ci->i_fragtree_mutex);
+       ret = __ceph_choose_frag(ci, v, pfrag, found);
+       mutex_unlock(&ci->i_fragtree_mutex);
+       return ret;
+}
+
+/*
+ * Process dirfrag (delegation) info from the mds.  Include leaf
+ * fragment in tree ONLY if ndist > 0.  Otherwise, only
+ * branches/splits are included in i_fragtree)
+ */
+static int ceph_fill_dirfrag(struct inode *inode,
+                            struct ceph_mds_reply_dirfrag *dirinfo)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       struct ceph_inode_frag *frag;
+       u32 id = le32_to_cpu(dirinfo->frag);
+       int mds = le32_to_cpu(dirinfo->auth);
+       int ndist = le32_to_cpu(dirinfo->ndist);
+       int diri_auth = -1;
+       int i;
+       int err = 0;
+
+       spin_lock(&ci->i_ceph_lock);
+       if (ci->i_auth_cap)
+               diri_auth = ci->i_auth_cap->mds;
+       spin_unlock(&ci->i_ceph_lock);
+
+       mutex_lock(&ci->i_fragtree_mutex);
+       if (ndist == 0 && mds == diri_auth) {
+               /* no delegation info needed. */
+               frag = __ceph_find_frag(ci, id);
+               if (!frag)
+                       goto out;
+               if (frag->split_by == 0) {
+                       /* tree leaf, remove */
+                       dout("fill_dirfrag removed %llx.%llx frag %x"
+                            " (no ref)\n", ceph_vinop(inode), id);
+                       rb_erase(&frag->node, &ci->i_fragtree);
+                       kfree(frag);
+               } else {
+                       /* tree branch, keep and clear */
+                       dout("fill_dirfrag cleared %llx.%llx frag %x"
+                            " referral\n", ceph_vinop(inode), id);
+                       frag->mds = -1;
+                       frag->ndist = 0;
+               }
+               goto out;
+       }
+
+
+       /* find/add this frag to store mds delegation info */
+       frag = __get_or_create_frag(ci, id);
+       if (IS_ERR(frag)) {
+               /* this is not the end of the world; we can continue
+                  with bad/inaccurate delegation info */
+               pr_err("fill_dirfrag ENOMEM on mds ref %llx.%llx fg %x\n",
+                      ceph_vinop(inode), le32_to_cpu(dirinfo->frag));
+               err = -ENOMEM;
+               goto out;
+       }
+
+       frag->mds = mds;
+       frag->ndist = min_t(u32, ndist, CEPH_MAX_DIRFRAG_REP);
+       for (i = 0; i < frag->ndist; i++)
+               frag->dist[i] = le32_to_cpu(dirinfo->dist[i]);
+       dout("fill_dirfrag %llx.%llx frag %x ndist=%d\n",
+            ceph_vinop(inode), frag->frag, frag->ndist);
+
+out:
+       mutex_unlock(&ci->i_fragtree_mutex);
+       return err;
+}
+
+static int ceph_fill_fragtree(struct inode *inode,
+                             struct ceph_frag_tree_head *fragtree,
+                             struct ceph_mds_reply_dirfrag *dirinfo)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       struct ceph_inode_frag *frag;
+       struct rb_node *rb_node;
+       int i;
+       u32 id, nsplits;
+       bool update = false;
+
+       mutex_lock(&ci->i_fragtree_mutex);
+       nsplits = le32_to_cpu(fragtree->nsplits);
+       if (nsplits) {
+               i = prandom_u32() % nsplits;
+               id = le32_to_cpu(fragtree->splits[i].frag);
+               if (!__ceph_find_frag(ci, id))
+                       update = true;
+       } else if (!RB_EMPTY_ROOT(&ci->i_fragtree)) {
+               rb_node = rb_first(&ci->i_fragtree);
+               frag = rb_entry(rb_node, struct ceph_inode_frag, node);
+               if (frag->frag != ceph_frag_make(0, 0) || rb_next(rb_node))
+                       update = true;
+       }
+       if (!update && dirinfo) {
+               id = le32_to_cpu(dirinfo->frag);
+               if (id != __ceph_choose_frag(ci, id, NULL, NULL))
+                       update = true;
+       }
+       if (!update)
+               goto out_unlock;
+
+       dout("fill_fragtree %llx.%llx\n", ceph_vinop(inode));
+       rb_node = rb_first(&ci->i_fragtree);
+       for (i = 0; i < nsplits; i++) {
+               id = le32_to_cpu(fragtree->splits[i].frag);
+               frag = NULL;
+               while (rb_node) {
+                       frag = rb_entry(rb_node, struct ceph_inode_frag, node);
+                       if (ceph_frag_compare(frag->frag, id) >= 0) {
+                               if (frag->frag != id)
+                                       frag = NULL;
+                               else
+                                       rb_node = rb_next(rb_node);
+                               break;
+                       }
+                       rb_node = rb_next(rb_node);
+                       rb_erase(&frag->node, &ci->i_fragtree);
+                       kfree(frag);
+                       frag = NULL;
+               }
+               if (!frag) {
+                       frag = __get_or_create_frag(ci, id);
+                       if (IS_ERR(frag))
+                               continue;
+               }
+               frag->split_by = le32_to_cpu(fragtree->splits[i].by);
+               dout(" frag %x split by %d\n", frag->frag, frag->split_by);
+       }
+       while (rb_node) {
+               frag = rb_entry(rb_node, struct ceph_inode_frag, node);
+               rb_node = rb_next(rb_node);
+               rb_erase(&frag->node, &ci->i_fragtree);
+               kfree(frag);
+       }
+out_unlock:
+       mutex_unlock(&ci->i_fragtree_mutex);
+       return 0;
+}
+
+/*
+ * initialize a newly allocated inode.
+ */
+struct inode *ceph_alloc_inode(struct super_block *sb)
+{
+       struct ceph_inode_info *ci;
+       int i;
+
+       ci = kmem_cache_alloc(ceph_inode_cachep, GFP_NOFS);
+       if (!ci)
+               return NULL;
+
+       dout("alloc_inode %p\n", &ci->vfs_inode);
+
+       spin_lock_init(&ci->i_ceph_lock);
+
+       ci->i_version = 0;
+       ci->i_inline_version = 0;
+       ci->i_time_warp_seq = 0;
+       ci->i_ceph_flags = 0;
+       ci->i_ordered_count = 0;
+       atomic_set(&ci->i_release_count, 1);
+       atomic_set(&ci->i_complete_count, 0);
+       ci->i_symlink = NULL;
+
+       memset(&ci->i_dir_layout, 0, sizeof(ci->i_dir_layout));
+
+       ci->i_fragtree = RB_ROOT;
+       mutex_init(&ci->i_fragtree_mutex);
+
+       ci->i_xattrs.blob = NULL;
+       ci->i_xattrs.prealloc_blob = NULL;
+       ci->i_xattrs.dirty = false;
+       ci->i_xattrs.index = RB_ROOT;
+       ci->i_xattrs.count = 0;
+       ci->i_xattrs.names_size = 0;
+       ci->i_xattrs.vals_size = 0;
+       ci->i_xattrs.version = 0;
+       ci->i_xattrs.index_version = 0;
+
+       ci->i_caps = RB_ROOT;
+       ci->i_auth_cap = NULL;
+       ci->i_dirty_caps = 0;
+       ci->i_flushing_caps = 0;
+       INIT_LIST_HEAD(&ci->i_dirty_item);
+       INIT_LIST_HEAD(&ci->i_flushing_item);
+       ci->i_cap_flush_seq = 0;
+       ci->i_cap_flush_last_tid = 0;
+       memset(&ci->i_cap_flush_tid, 0, sizeof(ci->i_cap_flush_tid));
+       init_waitqueue_head(&ci->i_cap_wq);
+       ci->i_hold_caps_min = 0;
+       ci->i_hold_caps_max = 0;
+       INIT_LIST_HEAD(&ci->i_cap_delay_list);
+       INIT_LIST_HEAD(&ci->i_cap_snaps);
+       ci->i_head_snapc = NULL;
+       ci->i_snap_caps = 0;
+
+       for (i = 0; i < CEPH_FILE_MODE_NUM; i++)
+               ci->i_nr_by_mode[i] = 0;
+
+       mutex_init(&ci->i_truncate_mutex);
+       ci->i_truncate_seq = 0;
+       ci->i_truncate_size = 0;
+       ci->i_truncate_pending = 0;
+
+       ci->i_max_size = 0;
+       ci->i_reported_size = 0;
+       ci->i_wanted_max_size = 0;
+       ci->i_requested_max_size = 0;
+
+       ci->i_pin_ref = 0;
+       ci->i_rd_ref = 0;
+       ci->i_rdcache_ref = 0;
+       ci->i_wr_ref = 0;
+       ci->i_wb_ref = 0;
+       ci->i_wrbuffer_ref = 0;
+       ci->i_wrbuffer_ref_head = 0;
+       ci->i_shared_gen = 0;
+       ci->i_rdcache_gen = 0;
+       ci->i_rdcache_revoking = 0;
+
+       INIT_LIST_HEAD(&ci->i_unsafe_writes);
+       INIT_LIST_HEAD(&ci->i_unsafe_dirops);
+       spin_lock_init(&ci->i_unsafe_lock);
+
+       ci->i_snap_realm = NULL;
+       INIT_LIST_HEAD(&ci->i_snap_realm_item);
+       INIT_LIST_HEAD(&ci->i_snap_flush_item);
+
+       INIT_WORK(&ci->i_wb_work, ceph_writeback_work);
+       INIT_WORK(&ci->i_pg_inv_work, ceph_invalidate_work);
+
+       INIT_WORK(&ci->i_vmtruncate_work, ceph_vmtruncate_work);
+
+       ceph_fscache_inode_init(ci);
+
+       return &ci->vfs_inode;
+}
+
+static void ceph_i_callback(struct rcu_head *head)
+{
+       struct inode *inode = container_of(head, struct inode, i_rcu);
+       struct ceph_inode_info *ci = ceph_inode(inode);
+
+       kmem_cache_free(ceph_inode_cachep, ci);
+}
+
+void ceph_destroy_inode(struct inode *inode)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       struct ceph_inode_frag *frag;
+       struct rb_node *n;
+
+       dout("destroy_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
+
+       ceph_fscache_unregister_inode_cookie(ci);
+
+       ceph_queue_caps_release(inode);
+
+       /*
+        * we may still have a snap_realm reference if there are stray
+        * caps in i_snap_caps.
+        */
+       if (ci->i_snap_realm) {
+               struct ceph_mds_client *mdsc =
+                       ceph_sb_to_client(ci->vfs_inode.i_sb)->mdsc;
+               struct ceph_snap_realm *realm = ci->i_snap_realm;
+
+               dout(" dropping residual ref to snap realm %p\n", realm);
+               spin_lock(&realm->inodes_with_caps_lock);
+               list_del_init(&ci->i_snap_realm_item);
+               spin_unlock(&realm->inodes_with_caps_lock);
+               ceph_put_snap_realm(mdsc, realm);
+       }
+
+       kfree(ci->i_symlink);
+       while ((n = rb_first(&ci->i_fragtree)) != NULL) {
+               frag = rb_entry(n, struct ceph_inode_frag, node);
+               rb_erase(n, &ci->i_fragtree);
+               kfree(frag);
+       }
+
+       __ceph_destroy_xattrs(ci);
+       if (ci->i_xattrs.blob)
+               ceph_buffer_put(ci->i_xattrs.blob);
+       if (ci->i_xattrs.prealloc_blob)
+               ceph_buffer_put(ci->i_xattrs.prealloc_blob);
+
+       call_rcu(&inode->i_rcu, ceph_i_callback);
+}
+
+int ceph_drop_inode(struct inode *inode)
+{
+       /*
+        * Positve dentry and corresponding inode are always accompanied
+        * in MDS reply. So no need to keep inode in the cache after
+        * dropping all its aliases.
+        */
+       return 1;
+}
+
+/*
+ * Helpers to fill in size, ctime, mtime, and atime.  We have to be
+ * careful because either the client or MDS may have more up to date
+ * info, depending on which capabilities are held, and whether
+ * time_warp_seq or truncate_seq have increased.  (Ordinarily, mtime
+ * and size are monotonically increasing, except when utimes() or
+ * truncate() increments the corresponding _seq values.)
+ */
+int ceph_fill_file_size(struct inode *inode, int issued,
+                       u32 truncate_seq, u64 truncate_size, u64 size)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       int queue_trunc = 0;
+
+       if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) > 0 ||
+           (truncate_seq == ci->i_truncate_seq && size > inode->i_size)) {
+               dout("size %lld -> %llu\n", inode->i_size, size);
+               inode->i_size = size;
+               inode->i_blocks = (size + (1<<9) - 1) >> 9;
+               ci->i_reported_size = size;
+               if (truncate_seq != ci->i_truncate_seq) {
+                       dout("truncate_seq %u -> %u\n",
+                            ci->i_truncate_seq, truncate_seq);
+                       ci->i_truncate_seq = truncate_seq;
+
+                       /* the MDS should have revoked these caps */
+                       WARN_ON_ONCE(issued & (CEPH_CAP_FILE_EXCL |
+                                              CEPH_CAP_FILE_RD |
+                                              CEPH_CAP_FILE_WR |
+                                              CEPH_CAP_FILE_LAZYIO));
+                       /*
+                        * If we hold relevant caps, or in the case where we're
+                        * not the only client referencing this file and we
+                        * don't hold those caps, then we need to check whether
+                        * the file is either opened or mmaped
+                        */
+                       if ((issued & (CEPH_CAP_FILE_CACHE|
+                                      CEPH_CAP_FILE_BUFFER)) ||
+                           mapping_mapped(inode->i_mapping) ||
+                           __ceph_caps_file_wanted(ci)) {
+                               ci->i_truncate_pending++;
+                               queue_trunc = 1;
+                       }
+               }
+       }
+       if (ceph_seq_cmp(truncate_seq, ci->i_truncate_seq) >= 0 &&
+           ci->i_truncate_size != truncate_size) {
+               dout("truncate_size %lld -> %llu\n", ci->i_truncate_size,
+                    truncate_size);
+               ci->i_truncate_size = truncate_size;
+       }
+
+       if (queue_trunc)
+               ceph_fscache_invalidate(inode);
+
+       return queue_trunc;
+}
+
+void ceph_fill_file_time(struct inode *inode, int issued,
+                        u64 time_warp_seq, struct timespec *ctime,
+                        struct timespec *mtime, struct timespec *atime)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       int warn = 0;
+
+       if (issued & (CEPH_CAP_FILE_EXCL|
+                     CEPH_CAP_FILE_WR|
+                     CEPH_CAP_FILE_BUFFER|
+                     CEPH_CAP_AUTH_EXCL|
+                     CEPH_CAP_XATTR_EXCL)) {
+               if (timespec_compare(ctime, &inode->i_ctime) > 0) {
+                       dout("ctime %ld.%09ld -> %ld.%09ld inc w/ cap\n",
+                            inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
+                            ctime->tv_sec, ctime->tv_nsec);
+                       inode->i_ctime = *ctime;
+               }
+               if (ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) > 0) {
+                       /* the MDS did a utimes() */
+                       dout("mtime %ld.%09ld -> %ld.%09ld "
+                            "tw %d -> %d\n",
+                            inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
+                            mtime->tv_sec, mtime->tv_nsec,
+                            ci->i_time_warp_seq, (int)time_warp_seq);
+
+                       inode->i_mtime = *mtime;
+                       inode->i_atime = *atime;
+                       ci->i_time_warp_seq = time_warp_seq;
+               } else if (time_warp_seq == ci->i_time_warp_seq) {
+                       /* nobody did utimes(); take the max */
+                       if (timespec_compare(mtime, &inode->i_mtime) > 0) {
+                               dout("mtime %ld.%09ld -> %ld.%09ld inc\n",
+                                    inode->i_mtime.tv_sec,
+                                    inode->i_mtime.tv_nsec,
+                                    mtime->tv_sec, mtime->tv_nsec);
+                               inode->i_mtime = *mtime;
+                       }
+                       if (timespec_compare(atime, &inode->i_atime) > 0) {
+                               dout("atime %ld.%09ld -> %ld.%09ld inc\n",
+                                    inode->i_atime.tv_sec,
+                                    inode->i_atime.tv_nsec,
+                                    atime->tv_sec, atime->tv_nsec);
+                               inode->i_atime = *atime;
+                       }
+               } else if (issued & CEPH_CAP_FILE_EXCL) {
+                       /* we did a utimes(); ignore mds values */
+               } else {
+                       warn = 1;
+               }
+       } else {
+               /* we have no write|excl caps; whatever the MDS says is true */
+               if (ceph_seq_cmp(time_warp_seq, ci->i_time_warp_seq) >= 0) {
+                       inode->i_ctime = *ctime;
+                       inode->i_mtime = *mtime;
+                       inode->i_atime = *atime;
+                       ci->i_time_warp_seq = time_warp_seq;
+               } else {
+                       warn = 1;
+               }
+       }
+       if (warn) /* time_warp_seq shouldn't go backwards */
+               dout("%p mds time_warp_seq %llu < %u\n",
+                    inode, time_warp_seq, ci->i_time_warp_seq);
+}
+
+/*
+ * Populate an inode based on info from mds.  May be called on new or
+ * existing inodes.
+ */
+static int fill_inode(struct inode *inode, struct page *locked_page,
+                     struct ceph_mds_reply_info_in *iinfo,
+                     struct ceph_mds_reply_dirfrag *dirinfo,
+                     struct ceph_mds_session *session,
+                     unsigned long ttl_from, int cap_fmode,
+                     struct ceph_cap_reservation *caps_reservation)
+{
+       struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
+       struct ceph_mds_reply_inode *info = iinfo->in;
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       int issued = 0, implemented, new_issued;
+       struct timespec mtime, atime, ctime;
+       struct ceph_buffer *xattr_blob = NULL;
+       struct ceph_cap *new_cap = NULL;
+       int err = 0;
+       bool wake = false;
+       bool queue_trunc = false;
+       bool new_version = false;
+       bool fill_inline = false;
+
+       dout("fill_inode %p ino %llx.%llx v %llu had %llu\n",
+            inode, ceph_vinop(inode), le64_to_cpu(info->version),
+            ci->i_version);
+
+       /* prealloc new cap struct */
+       if (info->cap.caps && ceph_snap(inode) == CEPH_NOSNAP)
+               new_cap = ceph_get_cap(mdsc, caps_reservation);
+
+       /*
+        * prealloc xattr data, if it looks like we'll need it.  only
+        * if len > 4 (meaning there are actually xattrs; the first 4
+        * bytes are the xattr count).
+        */
+       if (iinfo->xattr_len > 4) {
+               xattr_blob = ceph_buffer_new(iinfo->xattr_len, GFP_NOFS);
+               if (!xattr_blob)
+                       pr_err("fill_inode ENOMEM xattr blob %d bytes\n",
+                              iinfo->xattr_len);
+       }
+
+       spin_lock(&ci->i_ceph_lock);
+
+       /*
+        * provided version will be odd if inode value is projected,
+        * even if stable.  skip the update if we have newer stable
+        * info (ours>=theirs, e.g. due to racing mds replies), unless
+        * we are getting projected (unstable) info (in which case the
+        * version is odd, and we want ours>theirs).
+        *   us   them
+        *   2    2     skip
+        *   3    2     skip
+        *   3    3     update
+        */
+       if (ci->i_version == 0 ||
+           ((info->cap.flags & CEPH_CAP_FLAG_AUTH) &&
+            le64_to_cpu(info->version) > (ci->i_version & ~1)))
+               new_version = true;
+
+       issued = __ceph_caps_issued(ci, &implemented);
+       issued |= implemented | __ceph_caps_dirty(ci);
+       new_issued = ~issued & le32_to_cpu(info->cap.caps);
+
+       /* update inode */
+       ci->i_version = le64_to_cpu(info->version);
+       inode->i_version++;
+       inode->i_rdev = le32_to_cpu(info->rdev);
+       inode->i_blkbits = fls(le32_to_cpu(info->layout.fl_stripe_unit)) - 1;
+
+       if ((new_version || (new_issued & CEPH_CAP_AUTH_SHARED)) &&
+           (issued & CEPH_CAP_AUTH_EXCL) == 0) {
+               inode->i_mode = le32_to_cpu(info->mode);
+               inode->i_uid = make_kuid(&init_user_ns, le32_to_cpu(info->uid));
+               inode->i_gid = make_kgid(&init_user_ns, le32_to_cpu(info->gid));
+               dout("%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
+                    from_kuid(&init_user_ns, inode->i_uid),
+                    from_kgid(&init_user_ns, inode->i_gid));
+       }
+
+       if ((new_version || (new_issued & CEPH_CAP_LINK_SHARED)) &&
+           (issued & CEPH_CAP_LINK_EXCL) == 0)
+               set_nlink(inode, le32_to_cpu(info->nlink));
+
+       if (new_version || (new_issued & CEPH_CAP_ANY_RD)) {
+               /* be careful with mtime, atime, size */
+               ceph_decode_timespec(&atime, &info->atime);
+               ceph_decode_timespec(&mtime, &info->mtime);
+               ceph_decode_timespec(&ctime, &info->ctime);
+               ceph_fill_file_time(inode, issued,
+                               le32_to_cpu(info->time_warp_seq),
+                               &ctime, &mtime, &atime);
+       }
+
+       if (new_version ||
+           (new_issued & (CEPH_CAP_ANY_FILE_RD | CEPH_CAP_ANY_FILE_WR))) {
+               ci->i_layout = info->layout;
+               queue_trunc = ceph_fill_file_size(inode, issued,
+                                       le32_to_cpu(info->truncate_seq),
+                                       le64_to_cpu(info->truncate_size),
+                                       le64_to_cpu(info->size));
+               /* only update max_size on auth cap */
+               if ((info->cap.flags & CEPH_CAP_FLAG_AUTH) &&
+                   ci->i_max_size != le64_to_cpu(info->max_size)) {
+                       dout("max_size %lld -> %llu\n", ci->i_max_size,
+                                       le64_to_cpu(info->max_size));
+                       ci->i_max_size = le64_to_cpu(info->max_size);
+               }
+       }
+
+       /* xattrs */
+       /* note that if i_xattrs.len <= 4, i_xattrs.data will still be NULL. */
+       if ((ci->i_xattrs.version == 0 || !(issued & CEPH_CAP_XATTR_EXCL))  &&
+           le64_to_cpu(info->xattr_version) > ci->i_xattrs.version) {
+               if (ci->i_xattrs.blob)
+                       ceph_buffer_put(ci->i_xattrs.blob);
+               ci->i_xattrs.blob = xattr_blob;
+               if (xattr_blob)
+                       memcpy(ci->i_xattrs.blob->vec.iov_base,
+                              iinfo->xattr_data, iinfo->xattr_len);
+               ci->i_xattrs.version = le64_to_cpu(info->xattr_version);
+               ceph_forget_all_cached_acls(inode);
+               xattr_blob = NULL;
+       }
+
+       inode->i_mapping->a_ops = &ceph_aops;
+
+       switch (inode->i_mode & S_IFMT) {
+       case S_IFIFO:
+       case S_IFBLK:
+       case S_IFCHR:
+       case S_IFSOCK:
+               init_special_inode(inode, inode->i_mode, inode->i_rdev);
+               inode->i_op = &ceph_file_iops;
+               break;
+       case S_IFREG:
+               inode->i_op = &ceph_file_iops;
+               inode->i_fop = &ceph_file_fops;
+               break;
+       case S_IFLNK:
+               inode->i_op = &ceph_symlink_iops;
+               if (!ci->i_symlink) {
+                       u32 symlen = iinfo->symlink_len;
+                       char *sym;
+
+                       spin_unlock(&ci->i_ceph_lock);
+
+                       err = -EINVAL;
+                       if (WARN_ON(symlen != inode->i_size))
+                               goto out;
+
+                       err = -ENOMEM;
+                       sym = kstrndup(iinfo->symlink, symlen, GFP_NOFS);
+                       if (!sym)
+                               goto out;
+
+                       spin_lock(&ci->i_ceph_lock);
+                       if (!ci->i_symlink)
+                               ci->i_symlink = sym;
+                       else
+                               kfree(sym); /* lost a race */
+               }
+               break;
+       case S_IFDIR:
+               inode->i_op = &ceph_dir_iops;
+               inode->i_fop = &ceph_dir_fops;
+
+               ci->i_dir_layout = iinfo->dir_layout;
+
+               ci->i_files = le64_to_cpu(info->files);
+               ci->i_subdirs = le64_to_cpu(info->subdirs);
+               ci->i_rbytes = le64_to_cpu(info->rbytes);
+               ci->i_rfiles = le64_to_cpu(info->rfiles);
+               ci->i_rsubdirs = le64_to_cpu(info->rsubdirs);
+               ceph_decode_timespec(&ci->i_rctime, &info->rctime);
+               break;
+       default:
+               pr_err("fill_inode %llx.%llx BAD mode 0%o\n",
+                      ceph_vinop(inode), inode->i_mode);
+       }
+
+       /* were we issued a capability? */
+       if (info->cap.caps) {
+               if (ceph_snap(inode) == CEPH_NOSNAP) {
+                       unsigned caps = le32_to_cpu(info->cap.caps);
+                       ceph_add_cap(inode, session,
+                                    le64_to_cpu(info->cap.cap_id),
+                                    cap_fmode, caps,
+                                    le32_to_cpu(info->cap.wanted),
+                                    le32_to_cpu(info->cap.seq),
+                                    le32_to_cpu(info->cap.mseq),
+                                    le64_to_cpu(info->cap.realm),
+                                    info->cap.flags, &new_cap);
+
+                       /* set dir completion flag? */
+                       if (S_ISDIR(inode->i_mode) &&
+                           ci->i_files == 0 && ci->i_subdirs == 0 &&
+                           (caps & CEPH_CAP_FILE_SHARED) &&
+                           (issued & CEPH_CAP_FILE_EXCL) == 0 &&
+                           !__ceph_dir_is_complete(ci)) {
+                               dout(" marking %p complete (empty)\n", inode);
+                               __ceph_dir_set_complete(ci,
+                                       atomic_read(&ci->i_release_count),
+                                       ci->i_ordered_count);
+                       }
+
+                       wake = true;
+               } else {
+                       dout(" %p got snap_caps %s\n", inode,
+                            ceph_cap_string(le32_to_cpu(info->cap.caps)));
+                       ci->i_snap_caps |= le32_to_cpu(info->cap.caps);
+                       if (cap_fmode >= 0)
+                               __ceph_get_fmode(ci, cap_fmode);
+               }
+       } else if (cap_fmode >= 0) {
+               pr_warn("mds issued no caps on %llx.%llx\n",
+                          ceph_vinop(inode));
+               __ceph_get_fmode(ci, cap_fmode);
+       }
+
+       if (iinfo->inline_version > 0 &&
+           iinfo->inline_version >= ci->i_inline_version) {
+               int cache_caps = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO;
+               ci->i_inline_version = iinfo->inline_version;
+               if (ci->i_inline_version != CEPH_INLINE_NONE &&
+                   (locked_page ||
+                    (le32_to_cpu(info->cap.caps) & cache_caps)))
+                       fill_inline = true;
+       }
+
+       spin_unlock(&ci->i_ceph_lock);
+
+       if (fill_inline)
+               ceph_fill_inline_data(inode, locked_page,
+                                     iinfo->inline_data, iinfo->inline_len);
+
+       if (wake)
+               wake_up_all(&ci->i_cap_wq);
+
+       /* queue truncate if we saw i_size decrease */
+       if (queue_trunc)
+               ceph_queue_vmtruncate(inode);
+
+       /* populate frag tree */
+       if (S_ISDIR(inode->i_mode))
+               ceph_fill_fragtree(inode, &info->fragtree, dirinfo);
+
+       /* update delegation info? */
+       if (dirinfo)
+               ceph_fill_dirfrag(inode, dirinfo);
+
+       err = 0;
+out:
+       if (new_cap)
+               ceph_put_cap(mdsc, new_cap);
+       if (xattr_blob)
+               ceph_buffer_put(xattr_blob);
+       return err;
+}
+
+/*
+ * caller should hold session s_mutex.
+ */
+static void update_dentry_lease(struct dentry *dentry,
+                               struct ceph_mds_reply_lease *lease,
+                               struct ceph_mds_session *session,
+                               unsigned long from_time)
+{
+       struct ceph_dentry_info *di = ceph_dentry(dentry);
+       long unsigned duration = le32_to_cpu(lease->duration_ms);
+       long unsigned ttl = from_time + (duration * HZ) / 1000;
+       long unsigned half_ttl = from_time + (duration * HZ / 2) / 1000;
+       struct inode *dir;
+
+       /* only track leases on regular dentries */
+       if (dentry->d_op != &ceph_dentry_ops)
+               return;
+
+       spin_lock(&dentry->d_lock);
+       dout("update_dentry_lease %p duration %lu ms ttl %lu\n",
+            dentry, duration, ttl);
+
+       /* make lease_rdcache_gen match directory */
+       dir = d_inode(dentry->d_parent);
+       di->lease_shared_gen = ceph_inode(dir)->i_shared_gen;
+
+       if (duration == 0)
+               goto out_unlock;
+
+       if (di->lease_gen == session->s_cap_gen &&
+           time_before(ttl, dentry->d_time))
+               goto out_unlock;  /* we already have a newer lease. */
+
+       if (di->lease_session && di->lease_session != session)
+               goto out_unlock;
+
+       ceph_dentry_lru_touch(dentry);
+
+       if (!di->lease_session)
+               di->lease_session = ceph_get_mds_session(session);
+       di->lease_gen = session->s_cap_gen;
+       di->lease_seq = le32_to_cpu(lease->seq);
+       di->lease_renew_after = half_ttl;
+       di->lease_renew_from = 0;
+       dentry->d_time = ttl;
+out_unlock:
+       spin_unlock(&dentry->d_lock);
+       return;
+}
+
+/*
+ * splice a dentry to an inode.
+ * caller must hold directory i_mutex for this to be safe.
+ *
+ * we will only rehash the resulting dentry if @prehash is
+ * true; @prehash will be set to false (for the benefit of
+ * the caller) if we fail.
+ */
+static struct dentry *splice_dentry(struct dentry *dn, struct inode *in,
+                                   bool *prehash)
+{
+       struct dentry *realdn;
+
+       BUG_ON(d_inode(dn));
+
+       /* dn must be unhashed */
+       if (!d_unhashed(dn))
+               d_drop(dn);
+       realdn = d_splice_alias(in, dn);
+       if (IS_ERR(realdn)) {
+               pr_err("splice_dentry error %ld %p inode %p ino %llx.%llx\n",
+                      PTR_ERR(realdn), dn, in, ceph_vinop(in));
+               if (prehash)
+                       *prehash = false; /* don't rehash on error */
+               dn = realdn; /* note realdn contains the error */
+               goto out;
+       } else if (realdn) {
+               dout("dn %p (%d) spliced with %p (%d) "
+                    "inode %p ino %llx.%llx\n",
+                    dn, d_count(dn),
+                    realdn, d_count(realdn),
+                    d_inode(realdn), ceph_vinop(d_inode(realdn)));
+               dput(dn);
+               dn = realdn;
+       } else {
+               BUG_ON(!ceph_dentry(dn));
+               dout("dn %p attached to %p ino %llx.%llx\n",
+                    dn, d_inode(dn), ceph_vinop(d_inode(dn)));
+       }
+       if ((!prehash || *prehash) && d_unhashed(dn))
+               d_rehash(dn);
+out:
+       return dn;
+}
+
+/*
+ * Incorporate results into the local cache.  This is either just
+ * one inode, or a directory, dentry, and possibly linked-to inode (e.g.,
+ * after a lookup).
+ *
+ * A reply may contain
+ *         a directory inode along with a dentry.
+ *  and/or a target inode
+ *
+ * Called with snap_rwsem (read).
+ */
+int ceph_fill_trace(struct super_block *sb, struct ceph_mds_request *req,
+                   struct ceph_mds_session *session)
+{
+       struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
+       struct inode *in = NULL;
+       struct ceph_vino vino;
+       struct ceph_fs_client *fsc = ceph_sb_to_client(sb);
+       int err = 0;
+
+       dout("fill_trace %p is_dentry %d is_target %d\n", req,
+            rinfo->head->is_dentry, rinfo->head->is_target);
+
+#if 0
+       /*
+        * Debugging hook:
+        *
+        * If we resend completed ops to a recovering mds, we get no
+        * trace.  Since that is very rare, pretend this is the case
+        * to ensure the 'no trace' handlers in the callers behave.
+        *
+        * Fill in inodes unconditionally to avoid breaking cap
+        * invariants.
+        */
+       if (rinfo->head->op & CEPH_MDS_OP_WRITE) {
+               pr_info("fill_trace faking empty trace on %lld %s\n",
+                       req->r_tid, ceph_mds_op_name(rinfo->head->op));
+               if (rinfo->head->is_dentry) {
+                       rinfo->head->is_dentry = 0;
+                       err = fill_inode(req->r_locked_dir,
+                                        &rinfo->diri, rinfo->dirfrag,
+                                        session, req->r_request_started, -1);
+               }
+               if (rinfo->head->is_target) {
+                       rinfo->head->is_target = 0;
+                       ininfo = rinfo->targeti.in;
+                       vino.ino = le64_to_cpu(ininfo->ino);
+                       vino.snap = le64_to_cpu(ininfo->snapid);
+                       in = ceph_get_inode(sb, vino);
+                       err = fill_inode(in, &rinfo->targeti, NULL,
+                                        session, req->r_request_started,
+                                        req->r_fmode);
+                       iput(in);
+               }
+       }
+#endif
+
+       if (!rinfo->head->is_target && !rinfo->head->is_dentry) {
+               dout("fill_trace reply is empty!\n");
+               if (rinfo->head->result == 0 && req->r_locked_dir)
+                       ceph_invalidate_dir_request(req);
+               return 0;
+       }
+
+       if (rinfo->head->is_dentry) {
+               struct inode *dir = req->r_locked_dir;
+
+               if (dir) {
+                       err = fill_inode(dir, NULL,
+                                        &rinfo->diri, rinfo->dirfrag,
+                                        session, req->r_request_started, -1,
+                                        &req->r_caps_reservation);
+                       if (err < 0)
+                               goto done;
+               } else {
+                       WARN_ON_ONCE(1);
+               }
+
+               if (dir && req->r_op == CEPH_MDS_OP_LOOKUPNAME) {
+                       struct qstr dname;
+                       struct dentry *dn, *parent;
+
+                       BUG_ON(!rinfo->head->is_target);
+                       BUG_ON(req->r_dentry);
+
+                       parent = d_find_any_alias(dir);
+                       BUG_ON(!parent);
+
+                       dname.name = rinfo->dname;
+                       dname.len = rinfo->dname_len;
+                       dname.hash = full_name_hash(dname.name, dname.len);
+                       vino.ino = le64_to_cpu(rinfo->targeti.in->ino);
+                       vino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
+retry_lookup:
+                       dn = d_lookup(parent, &dname);
+                       dout("d_lookup on parent=%p name=%.*s got %p\n",
+                            parent, dname.len, dname.name, dn);
+
+                       if (!dn) {
+                               dn = d_alloc(parent, &dname);
+                               dout("d_alloc %p '%.*s' = %p\n", parent,
+                                    dname.len, dname.name, dn);
+                               if (dn == NULL) {
+                                       dput(parent);
+                                       err = -ENOMEM;
+                                       goto done;
+                               }
+                               err = ceph_init_dentry(dn);
+                               if (err < 0) {
+                                       dput(dn);
+                                       dput(parent);
+                                       goto done;
+                               }
+                       } else if (d_really_is_positive(dn) &&
+                                  (ceph_ino(d_inode(dn)) != vino.ino ||
+                                   ceph_snap(d_inode(dn)) != vino.snap)) {
+                               dout(" dn %p points to wrong inode %p\n",
+                                    dn, d_inode(dn));
+                               d_delete(dn);
+                               dput(dn);
+                               goto retry_lookup;
+                       }
+
+                       req->r_dentry = dn;
+                       dput(parent);
+               }
+       }
+
+       if (rinfo->head->is_target) {
+               vino.ino = le64_to_cpu(rinfo->targeti.in->ino);
+               vino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
+
+               in = ceph_get_inode(sb, vino);
+               if (IS_ERR(in)) {
+                       err = PTR_ERR(in);
+                       goto done;
+               }
+               req->r_target_inode = in;
+
+               err = fill_inode(in, req->r_locked_page, &rinfo->targeti, NULL,
+                               session, req->r_request_started,
+                               (!req->r_aborted && rinfo->head->result == 0) ?
+                               req->r_fmode : -1,
+                               &req->r_caps_reservation);
+               if (err < 0) {
+                       pr_err("fill_inode badness %p %llx.%llx\n",
+                               in, ceph_vinop(in));
+                       goto done;
+               }
+       }
+
+       /*
+        * ignore null lease/binding on snapdir ENOENT, or else we
+        * will have trouble splicing in the virtual snapdir later
+        */
+       if (rinfo->head->is_dentry && !req->r_aborted &&
+           req->r_locked_dir &&
+           (rinfo->head->is_target || strncmp(req->r_dentry->d_name.name,
+                                              fsc->mount_options->snapdir_name,
+                                              req->r_dentry->d_name.len))) {
+               /*
+                * lookup link rename   : null -> possibly existing inode
+                * mknod symlink mkdir  : null -> new inode
+                * unlink               : linked -> null
+                */
+               struct inode *dir = req->r_locked_dir;
+               struct dentry *dn = req->r_dentry;
+               bool have_dir_cap, have_lease;
+
+               BUG_ON(!dn);
+               BUG_ON(!dir);
+               BUG_ON(d_inode(dn->d_parent) != dir);
+               BUG_ON(ceph_ino(dir) !=
+                      le64_to_cpu(rinfo->diri.in->ino));
+               BUG_ON(ceph_snap(dir) !=
+                      le64_to_cpu(rinfo->diri.in->snapid));
+
+               /* do we have a lease on the whole dir? */
+               have_dir_cap =
+                       (le32_to_cpu(rinfo->diri.in->cap.caps) &
+                        CEPH_CAP_FILE_SHARED);
+
+               /* do we have a dn lease? */
+               have_lease = have_dir_cap ||
+                       le32_to_cpu(rinfo->dlease->duration_ms);
+               if (!have_lease)
+                       dout("fill_trace  no dentry lease or dir cap\n");
+
+               /* rename? */
+               if (req->r_old_dentry && req->r_op == CEPH_MDS_OP_RENAME) {
+                       struct inode *olddir = req->r_old_dentry_dir;
+                       BUG_ON(!olddir);
+
+                       dout(" src %p '%pd' dst %p '%pd'\n",
+                            req->r_old_dentry,
+                            req->r_old_dentry,
+                            dn, dn);
+                       dout("fill_trace doing d_move %p -> %p\n",
+                            req->r_old_dentry, dn);
+
+                       d_move(req->r_old_dentry, dn);
+                       dout(" src %p '%pd' dst %p '%pd'\n",
+                            req->r_old_dentry,
+                            req->r_old_dentry,
+                            dn, dn);
+
+                       /* ensure target dentry is invalidated, despite
+                          rehashing bug in vfs_rename_dir */
+                       ceph_invalidate_dentry_lease(dn);
+
+                       /* d_move screws up sibling dentries' offsets */
+                       ceph_dir_clear_ordered(dir);
+                       ceph_dir_clear_ordered(olddir);
+
+                       dout("dn %p gets new offset %lld\n", req->r_old_dentry,
+                            ceph_dentry(req->r_old_dentry)->offset);
+
+                       dn = req->r_old_dentry;  /* use old_dentry */
+               }
+
+               /* null dentry? */
+               if (!rinfo->head->is_target) {
+                       dout("fill_trace null dentry\n");
+                       if (d_really_is_positive(dn)) {
+                               ceph_dir_clear_ordered(dir);
+                               dout("d_delete %p\n", dn);
+                               d_delete(dn);
+                       } else {
+                               dout("d_instantiate %p NULL\n", dn);
+                               d_instantiate(dn, NULL);
+                               if (have_lease && d_unhashed(dn))
+                                       d_rehash(dn);
+                               update_dentry_lease(dn, rinfo->dlease,
+                                                   session,
+                                                   req->r_request_started);
+                       }
+                       goto done;
+               }
+
+               /* attach proper inode */
+               if (d_really_is_negative(dn)) {
+                       ceph_dir_clear_ordered(dir);
+                       ihold(in);
+                       dn = splice_dentry(dn, in, &have_lease);
+                       if (IS_ERR(dn)) {
+                               err = PTR_ERR(dn);
+                               goto done;
+                       }
+                       req->r_dentry = dn;  /* may have spliced */
+               } else if (d_really_is_positive(dn) && d_inode(dn) != in) {
+                       dout(" %p links to %p %llx.%llx, not %llx.%llx\n",
+                            dn, d_inode(dn), ceph_vinop(d_inode(dn)),
+                            ceph_vinop(in));
+                       have_lease = false;
+               }
+
+               if (have_lease)
+                       update_dentry_lease(dn, rinfo->dlease, session,
+                                           req->r_request_started);
+               dout(" final dn %p\n", dn);
+       } else if (!req->r_aborted &&
+                  (req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
+                   req->r_op == CEPH_MDS_OP_MKSNAP)) {
+               struct dentry *dn = req->r_dentry;
+               struct inode *dir = req->r_locked_dir;
+
+               /* fill out a snapdir LOOKUPSNAP dentry */
+               BUG_ON(!dn);
+               BUG_ON(!dir);
+               BUG_ON(ceph_snap(dir) != CEPH_SNAPDIR);
+               dout(" linking snapped dir %p to dn %p\n", in, dn);
+               ceph_dir_clear_ordered(dir);
+               ihold(in);
+               dn = splice_dentry(dn, in, NULL);
+               if (IS_ERR(dn)) {
+                       err = PTR_ERR(dn);
+                       goto done;
+               }
+               req->r_dentry = dn;  /* may have spliced */
+       }
+done:
+       dout("fill_trace done err=%d\n", err);
+       return err;
+}
+
+/*
+ * Prepopulate our cache with readdir results, leases, etc.
+ */
+static int readdir_prepopulate_inodes_only(struct ceph_mds_request *req,
+                                          struct ceph_mds_session *session)
+{
+       struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
+       int i, err = 0;
+
+       for (i = 0; i < rinfo->dir_nr; i++) {
+               struct ceph_vino vino;
+               struct inode *in;
+               int rc;
+
+               vino.ino = le64_to_cpu(rinfo->dir_in[i].in->ino);
+               vino.snap = le64_to_cpu(rinfo->dir_in[i].in->snapid);
+
+               in = ceph_get_inode(req->r_dentry->d_sb, vino);
+               if (IS_ERR(in)) {
+                       err = PTR_ERR(in);
+                       dout("new_inode badness got %d\n", err);
+                       continue;
+               }
+               rc = fill_inode(in, NULL, &rinfo->dir_in[i], NULL, session,
+                               req->r_request_started, -1,
+                               &req->r_caps_reservation);
+               if (rc < 0) {
+                       pr_err("fill_inode badness on %p got %d\n", in, rc);
+                       err = rc;
+                       continue;
+               }
+       }
+
+       return err;
+}
+
+int ceph_readdir_prepopulate(struct ceph_mds_request *req,
+                            struct ceph_mds_session *session)
+{
+       struct dentry *parent = req->r_dentry;
+       struct ceph_mds_reply_info_parsed *rinfo = &req->r_reply_info;
+       struct qstr dname;
+       struct dentry *dn;
+       struct inode *in;
+       int err = 0, ret, i;
+       struct inode *snapdir = NULL;
+       struct ceph_mds_request_head *rhead = req->r_request->front.iov_base;
+       struct ceph_dentry_info *di;
+       u64 r_readdir_offset = req->r_readdir_offset;
+       u32 frag = le32_to_cpu(rhead->args.readdir.frag);
+
+       if (rinfo->dir_dir &&
+           le32_to_cpu(rinfo->dir_dir->frag) != frag) {
+               dout("readdir_prepopulate got new frag %x -> %x\n",
+                    frag, le32_to_cpu(rinfo->dir_dir->frag));
+               frag = le32_to_cpu(rinfo->dir_dir->frag);
+               if (ceph_frag_is_leftmost(frag))
+                       r_readdir_offset = 2;
+               else
+                       r_readdir_offset = 0;
+       }
+
+       if (req->r_aborted)
+               return readdir_prepopulate_inodes_only(req, session);
+
+       if (le32_to_cpu(rinfo->head->op) == CEPH_MDS_OP_LSSNAP) {
+               snapdir = ceph_get_snapdir(d_inode(parent));
+               parent = d_find_alias(snapdir);
+               dout("readdir_prepopulate %d items under SNAPDIR dn %p\n",
+                    rinfo->dir_nr, parent);
+       } else {
+               dout("readdir_prepopulate %d items under dn %p\n",
+                    rinfo->dir_nr, parent);
+               if (rinfo->dir_dir)
+                       ceph_fill_dirfrag(d_inode(parent), rinfo->dir_dir);
+       }
+
+       /* FIXME: release caps/leases if error occurs */
+       for (i = 0; i < rinfo->dir_nr; i++) {
+               struct ceph_vino vino;
+
+               dname.name = rinfo->dir_dname[i];
+               dname.len = rinfo->dir_dname_len[i];
+               dname.hash = full_name_hash(dname.name, dname.len);
+
+               vino.ino = le64_to_cpu(rinfo->dir_in[i].in->ino);
+               vino.snap = le64_to_cpu(rinfo->dir_in[i].in->snapid);
+
+retry_lookup:
+               dn = d_lookup(parent, &dname);
+               dout("d_lookup on parent=%p name=%.*s got %p\n",
+                    parent, dname.len, dname.name, dn);
+
+               if (!dn) {
+                       dn = d_alloc(parent, &dname);
+                       dout("d_alloc %p '%.*s' = %p\n", parent,
+                            dname.len, dname.name, dn);
+                       if (dn == NULL) {
+                               dout("d_alloc badness\n");
+                               err = -ENOMEM;
+                               goto out;
+                       }
+                       ret = ceph_init_dentry(dn);
+                       if (ret < 0) {
+                               dput(dn);
+                               err = ret;
+                               goto out;
+                       }
+               } else if (d_really_is_positive(dn) &&
+                          (ceph_ino(d_inode(dn)) != vino.ino ||
+                           ceph_snap(d_inode(dn)) != vino.snap)) {
+                       dout(" dn %p points to wrong inode %p\n",
+                            dn, d_inode(dn));
+                       d_delete(dn);
+                       dput(dn);
+                       goto retry_lookup;
+               } else {
+                       /* reorder parent's d_subdirs */
+                       spin_lock(&parent->d_lock);
+                       spin_lock_nested(&dn->d_lock, DENTRY_D_LOCK_NESTED);
+                       list_move(&dn->d_child, &parent->d_subdirs);
+                       spin_unlock(&dn->d_lock);
+                       spin_unlock(&parent->d_lock);
+               }
+
+               /* inode */
+               if (d_really_is_positive(dn)) {
+                       in = d_inode(dn);
+               } else {
+                       in = ceph_get_inode(parent->d_sb, vino);
+                       if (IS_ERR(in)) {
+                               dout("new_inode badness\n");
+                               d_drop(dn);
+                               dput(dn);
+                               err = PTR_ERR(in);
+                               goto out;
+                       }
+               }
+
+               if (fill_inode(in, NULL, &rinfo->dir_in[i], NULL, session,
+                              req->r_request_started, -1,
+                              &req->r_caps_reservation) < 0) {
+                       pr_err("fill_inode badness on %p\n", in);
+                       if (d_really_is_negative(dn))
+                               iput(in);
+                       d_drop(dn);
+                       goto next_item;
+               }
+
+               if (d_really_is_negative(dn)) {
+                       struct dentry *realdn = splice_dentry(dn, in, NULL);
+                       if (IS_ERR(realdn)) {
+                               err = PTR_ERR(realdn);
+                               d_drop(dn);
+                               dn = NULL;
+                               goto next_item;
+                       }
+                       dn = realdn;
+               }
+
+               di = dn->d_fsdata;
+               di->offset = ceph_make_fpos(frag, i + r_readdir_offset);
+
+               update_dentry_lease(dn, rinfo->dir_dlease[i],
+                                   req->r_session,
+                                   req->r_request_started);
+next_item:
+               if (dn)
+                       dput(dn);
+       }
+       if (err == 0)
+               req->r_did_prepopulate = true;
+
+out:
+       if (snapdir) {
+               iput(snapdir);
+               dput(parent);
+       }
+       dout("readdir_prepopulate done\n");
+       return err;
+}
+
+int ceph_inode_set_size(struct inode *inode, loff_t size)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       int ret = 0;
+
+       spin_lock(&ci->i_ceph_lock);
+       dout("set_size %p %llu -> %llu\n", inode, inode->i_size, size);
+       inode->i_size = size;
+       inode->i_blocks = (size + (1 << 9) - 1) >> 9;
+
+       /* tell the MDS if we are approaching max_size */
+       if ((size << 1) >= ci->i_max_size &&
+           (ci->i_reported_size << 1) < ci->i_max_size)
+               ret = 1;
+
+       spin_unlock(&ci->i_ceph_lock);
+       return ret;
+}
+
+/*
+ * Write back inode data in a worker thread.  (This can't be done
+ * in the message handler context.)
+ */
+void ceph_queue_writeback(struct inode *inode)
+{
+       ihold(inode);
+       if (queue_work(ceph_inode_to_client(inode)->wb_wq,
+                      &ceph_inode(inode)->i_wb_work)) {
+               dout("ceph_queue_writeback %p\n", inode);
+       } else {
+               dout("ceph_queue_writeback %p failed\n", inode);
+               iput(inode);
+       }
+}
+
+static void ceph_writeback_work(struct work_struct *work)
+{
+       struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
+                                                 i_wb_work);
+       struct inode *inode = &ci->vfs_inode;
+
+       dout("writeback %p\n", inode);
+       filemap_fdatawrite(&inode->i_data);
+       iput(inode);
+}
+
+/*
+ * queue an async invalidation
+ */
+void ceph_queue_invalidate(struct inode *inode)
+{
+       ihold(inode);
+       if (queue_work(ceph_inode_to_client(inode)->pg_inv_wq,
+                      &ceph_inode(inode)->i_pg_inv_work)) {
+               dout("ceph_queue_invalidate %p\n", inode);
+       } else {
+               dout("ceph_queue_invalidate %p failed\n", inode);
+               iput(inode);
+       }
+}
+
+/*
+ * Invalidate inode pages in a worker thread.  (This can't be done
+ * in the message handler context.)
+ */
+static void ceph_invalidate_work(struct work_struct *work)
+{
+       struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
+                                                 i_pg_inv_work);
+       struct inode *inode = &ci->vfs_inode;
+       u32 orig_gen;
+       int check = 0;
+
+       mutex_lock(&ci->i_truncate_mutex);
+       spin_lock(&ci->i_ceph_lock);
+       dout("invalidate_pages %p gen %d revoking %d\n", inode,
+            ci->i_rdcache_gen, ci->i_rdcache_revoking);
+       if (ci->i_rdcache_revoking != ci->i_rdcache_gen) {
+               if (__ceph_caps_revoking_other(ci, NULL, CEPH_CAP_FILE_CACHE))
+                       check = 1;
+               spin_unlock(&ci->i_ceph_lock);
+               mutex_unlock(&ci->i_truncate_mutex);
+               goto out;
+       }
+       orig_gen = ci->i_rdcache_gen;
+       spin_unlock(&ci->i_ceph_lock);
+
+       truncate_pagecache(inode, 0);
+
+       spin_lock(&ci->i_ceph_lock);
+       if (orig_gen == ci->i_rdcache_gen &&
+           orig_gen == ci->i_rdcache_revoking) {
+               dout("invalidate_pages %p gen %d successful\n", inode,
+                    ci->i_rdcache_gen);
+               ci->i_rdcache_revoking--;
+               check = 1;
+       } else {
+               dout("invalidate_pages %p gen %d raced, now %d revoking %d\n",
+                    inode, orig_gen, ci->i_rdcache_gen,
+                    ci->i_rdcache_revoking);
+               if (__ceph_caps_revoking_other(ci, NULL, CEPH_CAP_FILE_CACHE))
+                       check = 1;
+       }
+       spin_unlock(&ci->i_ceph_lock);
+       mutex_unlock(&ci->i_truncate_mutex);
+out:
+       if (check)
+               ceph_check_caps(ci, 0, NULL);
+       iput(inode);
+}
+
+
+/*
+ * called by trunc_wq;
+ *
+ * We also truncate in a separate thread as well.
+ */
+static void ceph_vmtruncate_work(struct work_struct *work)
+{
+       struct ceph_inode_info *ci = container_of(work, struct ceph_inode_info,
+                                                 i_vmtruncate_work);
+       struct inode *inode = &ci->vfs_inode;
+
+       dout("vmtruncate_work %p\n", inode);
+       __ceph_do_pending_vmtruncate(inode);
+       iput(inode);
+}
+
+/*
+ * Queue an async vmtruncate.  If we fail to queue work, we will handle
+ * the truncation the next time we call __ceph_do_pending_vmtruncate.
+ */
+void ceph_queue_vmtruncate(struct inode *inode)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+
+       ihold(inode);
+
+       if (queue_work(ceph_sb_to_client(inode->i_sb)->trunc_wq,
+                      &ci->i_vmtruncate_work)) {
+               dout("ceph_queue_vmtruncate %p\n", inode);
+       } else {
+               dout("ceph_queue_vmtruncate %p failed, pending=%d\n",
+                    inode, ci->i_truncate_pending);
+               iput(inode);
+       }
+}
+
+/*
+ * Make sure any pending truncation is applied before doing anything
+ * that may depend on it.
+ */
+void __ceph_do_pending_vmtruncate(struct inode *inode)
+{
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       u64 to;
+       int wrbuffer_refs, finish = 0;
+
+       mutex_lock(&ci->i_truncate_mutex);
+retry:
+       spin_lock(&ci->i_ceph_lock);
+       if (ci->i_truncate_pending == 0) {
+               dout("__do_pending_vmtruncate %p none pending\n", inode);
+               spin_unlock(&ci->i_ceph_lock);
+               mutex_unlock(&ci->i_truncate_mutex);
+               return;
+       }
+
+       /*
+        * make sure any dirty snapped pages are flushed before we
+        * possibly truncate them.. so write AND block!
+        */
+       if (ci->i_wrbuffer_ref_head < ci->i_wrbuffer_ref) {
+               dout("__do_pending_vmtruncate %p flushing snaps first\n",
+                    inode);
+               spin_unlock(&ci->i_ceph_lock);
+               filemap_write_and_wait_range(&inode->i_data, 0,
+                                            inode->i_sb->s_maxbytes);
+               goto retry;
+       }
+
+       /* there should be no reader or writer */
+       WARN_ON_ONCE(ci->i_rd_ref || ci->i_wr_ref);
+
+       to = ci->i_truncate_size;
+       wrbuffer_refs = ci->i_wrbuffer_ref;
+       dout("__do_pending_vmtruncate %p (%d) to %lld\n", inode,
+            ci->i_truncate_pending, to);
+       spin_unlock(&ci->i_ceph_lock);
+
+       truncate_pagecache(inode, to);
+
+       spin_lock(&ci->i_ceph_lock);
+       if (to == ci->i_truncate_size) {
+               ci->i_truncate_pending = 0;
+               finish = 1;
+       }
+       spin_unlock(&ci->i_ceph_lock);
+       if (!finish)
+               goto retry;
+
+       mutex_unlock(&ci->i_truncate_mutex);
+
+       if (wrbuffer_refs == 0)
+               ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
+
+       wake_up_all(&ci->i_cap_wq);
+}
+
+/*
+ * symlinks
+ */
+static void *ceph_sym_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+       struct ceph_inode_info *ci = ceph_inode(d_inode(dentry));
+       nd_set_link(nd, ci->i_symlink);
+       return NULL;
+}
+
+static const struct inode_operations ceph_symlink_iops = {
+       .readlink = generic_readlink,
+       .follow_link = ceph_sym_follow_link,
+       .setattr = ceph_setattr,
+       .getattr = ceph_getattr,
+       .setxattr = ceph_setxattr,
+       .getxattr = ceph_getxattr,
+       .listxattr = ceph_listxattr,
+       .removexattr = ceph_removexattr,
+};
+
+/*
+ * setattr
+ */
+int ceph_setattr(struct dentry *dentry, struct iattr *attr)
+{
+       struct inode *inode = d_inode(dentry);
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       const unsigned int ia_valid = attr->ia_valid;
+       struct ceph_mds_request *req;
+       struct ceph_mds_client *mdsc = ceph_sb_to_client(dentry->d_sb)->mdsc;
+       int issued;
+       int release = 0, dirtied = 0;
+       int mask = 0;
+       int err = 0;
+       int inode_dirty_flags = 0;
+
+       if (ceph_snap(inode) != CEPH_NOSNAP)
+               return -EROFS;
+
+       err = inode_change_ok(inode, attr);
+       if (err != 0)
+               return err;
+
+       req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETATTR,
+                                      USE_AUTH_MDS);
+       if (IS_ERR(req))
+               return PTR_ERR(req);
+
+       spin_lock(&ci->i_ceph_lock);
+       issued = __ceph_caps_issued(ci, NULL);
+       dout("setattr %p issued %s\n", inode, ceph_cap_string(issued));
+
+       if (ia_valid & ATTR_UID) {
+               dout("setattr %p uid %d -> %d\n", inode,
+                    from_kuid(&init_user_ns, inode->i_uid),
+                    from_kuid(&init_user_ns, attr->ia_uid));
+               if (issued & CEPH_CAP_AUTH_EXCL) {
+                       inode->i_uid = attr->ia_uid;
+                       dirtied |= CEPH_CAP_AUTH_EXCL;
+               } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
+                          !uid_eq(attr->ia_uid, inode->i_uid)) {
+                       req->r_args.setattr.uid = cpu_to_le32(
+                               from_kuid(&init_user_ns, attr->ia_uid));
+                       mask |= CEPH_SETATTR_UID;
+                       release |= CEPH_CAP_AUTH_SHARED;
+               }
+       }
+       if (ia_valid & ATTR_GID) {
+               dout("setattr %p gid %d -> %d\n", inode,
+                    from_kgid(&init_user_ns, inode->i_gid),
+                    from_kgid(&init_user_ns, attr->ia_gid));
+               if (issued & CEPH_CAP_AUTH_EXCL) {
+                       inode->i_gid = attr->ia_gid;
+                       dirtied |= CEPH_CAP_AUTH_EXCL;
+               } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
+                          !gid_eq(attr->ia_gid, inode->i_gid)) {
+                       req->r_args.setattr.gid = cpu_to_le32(
+                               from_kgid(&init_user_ns, attr->ia_gid));
+                       mask |= CEPH_SETATTR_GID;
+                       release |= CEPH_CAP_AUTH_SHARED;
+               }
+       }
+       if (ia_valid & ATTR_MODE) {
+               dout("setattr %p mode 0%o -> 0%o\n", inode, inode->i_mode,
+                    attr->ia_mode);
+               if (issued & CEPH_CAP_AUTH_EXCL) {
+                       inode->i_mode = attr->ia_mode;
+                       dirtied |= CEPH_CAP_AUTH_EXCL;
+               } else if ((issued & CEPH_CAP_AUTH_SHARED) == 0 ||
+                          attr->ia_mode != inode->i_mode) {
+                       inode->i_mode = attr->ia_mode;
+                       req->r_args.setattr.mode = cpu_to_le32(attr->ia_mode);
+                       mask |= CEPH_SETATTR_MODE;
+                       release |= CEPH_CAP_AUTH_SHARED;
+               }
+       }
+
+       if (ia_valid & ATTR_ATIME) {
+               dout("setattr %p atime %ld.%ld -> %ld.%ld\n", inode,
+                    inode->i_atime.tv_sec, inode->i_atime.tv_nsec,
+                    attr->ia_atime.tv_sec, attr->ia_atime.tv_nsec);
+               if (issued & CEPH_CAP_FILE_EXCL) {
+                       ci->i_time_warp_seq++;
+                       inode->i_atime = attr->ia_atime;
+                       dirtied |= CEPH_CAP_FILE_EXCL;
+               } else if ((issued & CEPH_CAP_FILE_WR) &&
+                          timespec_compare(&inode->i_atime,
+                                           &attr->ia_atime) < 0) {
+                       inode->i_atime = attr->ia_atime;
+                       dirtied |= CEPH_CAP_FILE_WR;
+               } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
+                          !timespec_equal(&inode->i_atime, &attr->ia_atime)) {
+                       ceph_encode_timespec(&req->r_args.setattr.atime,
+                                            &attr->ia_atime);
+                       mask |= CEPH_SETATTR_ATIME;
+                       release |= CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_RD |
+                               CEPH_CAP_FILE_WR;
+               }
+       }
+       if (ia_valid & ATTR_MTIME) {
+               dout("setattr %p mtime %ld.%ld -> %ld.%ld\n", inode,
+                    inode->i_mtime.tv_sec, inode->i_mtime.tv_nsec,
+                    attr->ia_mtime.tv_sec, attr->ia_mtime.tv_nsec);
+               if (issued & CEPH_CAP_FILE_EXCL) {
+                       ci->i_time_warp_seq++;
+                       inode->i_mtime = attr->ia_mtime;
+                       dirtied |= CEPH_CAP_FILE_EXCL;
+               } else if ((issued & CEPH_CAP_FILE_WR) &&
+                          timespec_compare(&inode->i_mtime,
+                                           &attr->ia_mtime) < 0) {
+                       inode->i_mtime = attr->ia_mtime;
+                       dirtied |= CEPH_CAP_FILE_WR;
+               } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
+                          !timespec_equal(&inode->i_mtime, &attr->ia_mtime)) {
+                       ceph_encode_timespec(&req->r_args.setattr.mtime,
+                                            &attr->ia_mtime);
+                       mask |= CEPH_SETATTR_MTIME;
+                       release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
+                               CEPH_CAP_FILE_WR;
+               }
+       }
+       if (ia_valid & ATTR_SIZE) {
+               dout("setattr %p size %lld -> %lld\n", inode,
+                    inode->i_size, attr->ia_size);
+               if ((issued & CEPH_CAP_FILE_EXCL) &&
+                   attr->ia_size > inode->i_size) {
+                       inode->i_size = attr->ia_size;
+                       inode->i_blocks =
+                               (attr->ia_size + (1 << 9) - 1) >> 9;
+                       inode->i_ctime = attr->ia_ctime;
+                       ci->i_reported_size = attr->ia_size;
+                       dirtied |= CEPH_CAP_FILE_EXCL;
+               } else if ((issued & CEPH_CAP_FILE_SHARED) == 0 ||
+                          attr->ia_size != inode->i_size) {
+                       req->r_args.setattr.size = cpu_to_le64(attr->ia_size);
+                       req->r_args.setattr.old_size =
+                               cpu_to_le64(inode->i_size);
+                       mask |= CEPH_SETATTR_SIZE;
+                       release |= CEPH_CAP_FILE_SHARED | CEPH_CAP_FILE_RD |
+                               CEPH_CAP_FILE_WR;
+               }
+       }
+
+       /* these do nothing */
+       if (ia_valid & ATTR_CTIME) {
+               bool only = (ia_valid & (ATTR_SIZE|ATTR_MTIME|ATTR_ATIME|
+                                        ATTR_MODE|ATTR_UID|ATTR_GID)) == 0;
+               dout("setattr %p ctime %ld.%ld -> %ld.%ld (%s)\n", inode,
+                    inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
+                    attr->ia_ctime.tv_sec, attr->ia_ctime.tv_nsec,
+                    only ? "ctime only" : "ignored");
+               inode->i_ctime = attr->ia_ctime;
+               if (only) {
+                       /*
+                        * if kernel wants to dirty ctime but nothing else,
+                        * we need to choose a cap to dirty under, or do
+                        * a almost-no-op setattr
+                        */
+                       if (issued & CEPH_CAP_AUTH_EXCL)
+                               dirtied |= CEPH_CAP_AUTH_EXCL;
+                       else if (issued & CEPH_CAP_FILE_EXCL)
+                               dirtied |= CEPH_CAP_FILE_EXCL;
+                       else if (issued & CEPH_CAP_XATTR_EXCL)
+                               dirtied |= CEPH_CAP_XATTR_EXCL;
+                       else
+                               mask |= CEPH_SETATTR_CTIME;
+               }
+       }
+       if (ia_valid & ATTR_FILE)
+               dout("setattr %p ATTR_FILE ... hrm!\n", inode);
+
+       if (dirtied) {
+               inode_dirty_flags = __ceph_mark_dirty_caps(ci, dirtied);
+               inode->i_ctime = CURRENT_TIME;
+       }
+
+       release &= issued;
+       spin_unlock(&ci->i_ceph_lock);
+
+       if (inode_dirty_flags)
+               __mark_inode_dirty(inode, inode_dirty_flags);
+
+       if (ia_valid & ATTR_MODE) {
+               err = posix_acl_chmod(inode, attr->ia_mode);
+               if (err)
+                       goto out_put;
+       }
+
+       if (mask) {
+               req->r_inode = inode;
+               ihold(inode);
+               req->r_inode_drop = release;
+               req->r_args.setattr.mask = cpu_to_le32(mask);
+               req->r_num_caps = 1;
+               err = ceph_mdsc_do_request(mdsc, NULL, req);
+       }
+       dout("setattr %p result=%d (%s locally, %d remote)\n", inode, err,
+            ceph_cap_string(dirtied), mask);
+
+       ceph_mdsc_put_request(req);
+       if (mask & CEPH_SETATTR_SIZE)
+               __ceph_do_pending_vmtruncate(inode);
+       return err;
+out_put:
+       ceph_mdsc_put_request(req);
+       return err;
+}
+
+/*
+ * Verify that we have a lease on the given mask.  If not,
+ * do a getattr against an mds.
+ */
+int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
+                     int mask, bool force)
+{
+       struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb);
+       struct ceph_mds_client *mdsc = fsc->mdsc;
+       struct ceph_mds_request *req;
+       int err;
+
+       if (ceph_snap(inode) == CEPH_SNAPDIR) {
+               dout("do_getattr inode %p SNAPDIR\n", inode);
+               return 0;
+       }
+
+       dout("do_getattr inode %p mask %s mode 0%o\n",
+            inode, ceph_cap_string(mask), inode->i_mode);
+       if (!force && ceph_caps_issued_mask(ceph_inode(inode), mask, 1))
+               return 0;
+
+       req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, USE_ANY_MDS);
+       if (IS_ERR(req))
+               return PTR_ERR(req);
+       req->r_inode = inode;
+       ihold(inode);
+       req->r_num_caps = 1;
+       req->r_args.getattr.mask = cpu_to_le32(mask);
+       req->r_locked_page = locked_page;
+       err = ceph_mdsc_do_request(mdsc, NULL, req);
+       if (locked_page && err == 0) {
+               u64 inline_version = req->r_reply_info.targeti.inline_version;
+               if (inline_version == 0) {
+                       /* the reply is supposed to contain inline data */
+                       err = -EINVAL;
+               } else if (inline_version == CEPH_INLINE_NONE) {
+                       err = -ENODATA;
+               } else {
+                       err = req->r_reply_info.targeti.inline_len;
+               }
+       }
+       ceph_mdsc_put_request(req);
+       dout("do_getattr result=%d\n", err);
+       return err;
+}
+
+
+/*
+ * Check inode permissions.  We verify we have a valid value for
+ * the AUTH cap, then call the generic handler.
+ */
+int ceph_permission(struct inode *inode, int mask)
+{
+       int err;
+
+       if (mask & MAY_NOT_BLOCK)
+               return -ECHILD;
+
+       err = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED, false);
+
+       if (!err)
+               err = generic_permission(inode, mask);
+       return err;
+}
+
+/*
+ * Get all attributes.  Hopefully somedata we'll have a statlite()
+ * and can limit the fields we require to be accurate.
+ */
+int ceph_getattr(struct vfsmount *mnt, struct dentry *dentry,
+                struct kstat *stat)
+{
+       struct inode *inode = d_inode(dentry);
+       struct ceph_inode_info *ci = ceph_inode(inode);
+       int err;
+
+       err = ceph_do_getattr(inode, CEPH_STAT_CAP_INODE_ALL, false);
+       if (!err) {
+               generic_fillattr(inode, stat);
+               stat->ino = ceph_translate_ino(inode->i_sb, inode->i_ino);
+               if (ceph_snap(inode) != CEPH_NOSNAP)
+                       stat->dev = ceph_snap(inode);
+               else
+                       stat->dev = 0;
+               if (S_ISDIR(inode->i_mode)) {
+                       if (ceph_test_mount_opt(ceph_sb_to_client(inode->i_sb),
+                                               RBYTES))
+                               stat->size = ci->i_rbytes;
+                       else
+                               stat->size = ci->i_files + ci->i_subdirs;
+                       stat->blocks = 0;
+                       stat->blksize = 65536;
+               }
+       }
+       return err;
+}