[PATCH 06/21] ceph: inode operations

[Sage Weil]

Inode cache and inode operations.  We also include routines to
incorporate metadata structures returned by the MDS into the client
cache, and some helpers to deal with file capabilities and metadata
leases.  The bulk of that work is done by fill_inode() and
fill_trace().

Most MDS responses include a "trace" of dentry and inode information
from the inode in question back to the root.  fill_trace() takes pains
to ensure that the dcache is updated safely.  If the directory i_mutex
is not already held and cannot be taken (via trylock), that segment of
the trace is skipped.  If an inode is linked incorrectly, we attempt
to reattach it in the correct position in the hierarchy.

Signed-off-by: Sage Weil <sage@xxxxxxxxxxxx>
---
 fs/staging/ceph/inode.c | 2356 +++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 2356 insertions(+), 0 deletions(-)
 create mode 100644 fs/staging/ceph/inode.c

diff --git a/fs/staging/ceph/inode.c b/fs/staging/ceph/inode.c
new file mode 100644
index 0000000..06b062d
--- /dev/null
+++ b/fs/staging/ceph/inode.c
@@ -0,0 +1,2356 @@
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/smp_lock.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 "ceph_debug.h"
+
+int ceph_debug_inode __read_mostly = -1;
+#define DOUT_MASK DOUT_MASK_INODE
+#define DOUT_VAR ceph_debug_inode
+#include "super.h"
+#include "decode.h"
+
+static const struct inode_operations ceph_symlink_iops;
+
+static void ceph_inode_invalidate_pages(struct work_struct *work);
+
+static void __destroy_xattrs(struct ceph_inode_info *ci);
+
+/*
+ * find or create an inode, given the ceph ino number
+ */
+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(40, "get_inode created new inode %p %llx.%llx ino %llx\n",
+		     inode, ceph_vinop(inode), (u64)inode->i_ino);
+		unlock_new_inode(inode);
+	}
+
+	dout(30, "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);
+	if (IS_ERR(inode))
+		return ERR_PTR(PTR_ERR(inode));
+	inode->i_mode = parent->i_mode;
+	inode->i_uid = parent->i_uid;
+	inode->i_gid = parent->i_gid;
+	inode->i_op = &ceph_dir_iops;
+	inode->i_fop = &ceph_dir_fops;
+	ceph_inode(inode)->i_snap_caps = CEPH_CAP_PIN; /* so we can open */
+	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,
+};
+
+
+/*
+ * 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 = 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) {
+		derr(0, "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(20, "get_or_create_frag added %llx.%llx frag %x\n",
+	     ceph_vinop(&ci->vfs_inode), f);
+
+	return frag;
+}
+
+/*
+ * Choose frag containing the given value @v.  If @pfrag is
+ * specified, copy the frag delegation info to the caller if
+ * it is present.
+ */
+u32 ceph_choose_frag(struct ceph_inode_info *ci, u32 v,
+		       struct ceph_inode_frag *pfrag,
+		       int *found)
+{
+	u32 t = frag_make(0, 0);
+	struct ceph_inode_frag *frag;
+	unsigned nway, i;
+	u32 n;
+
+	if (found)
+		*found = 0;
+
+	mutex_lock(&ci->i_fragtree_mutex);
+	while (1) {
+		WARN_ON(!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(30, "choose_frag(%x) %x splits by %d (%d ways)\n", v, t,
+		     frag->split_by, nway);
+		for (i = 0; i < nway; i++) {
+			n = frag_make_child(t, frag->split_by, i);
+			if (frag_contains_value(n, v)) {
+				t = n;
+				break;
+			}
+		}
+		BUG_ON(i == nway);
+	}
+	dout(30, "choose_frag(%x) = %x\n", v, t);
+
+	mutex_unlock(&ci->i_fragtree_mutex);
+	return t;
+}
+
+/*
+ * Process dirfrag (delegation) info from the mds.  Include leaf
+ * fragment in tree ONLY if mds >= 0 || 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 i;
+	int err = 0;
+
+	mutex_lock(&ci->i_fragtree_mutex);
+	if (mds < 0 && ndist == 0) {
+		/* no delegation info needed. */
+		frag = __ceph_find_frag(ci, id);
+		if (!frag)
+			goto out;
+		if (frag->split_by == 0) {
+			/* tree leaf, remove */
+			dout(20, "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(20, "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 */
+		derr(0, "fill_dirfrag ENOMEM on mds ref %llx.%llx frag %x\n",
+		     ceph_vinop(inode), le32_to_cpu(dirinfo->frag));
+		err = -ENOMEM;
+		goto out;
+	}
+
+	frag->mds = mds;
+	frag->ndist = min_t(u32, ndist, MAX_DIRFRAG_REP);
+	for (i = 0; i < frag->ndist; i++)
+		frag->dist[i] = le32_to_cpu(dirinfo->dist[i]);
+	dout(20, "fill_dirfrag %llx.%llx frag %x referral mds %d ndist=%d\n",
+	     ceph_vinop(inode), frag->frag, frag->mds, frag->ndist);
+
+out:
+	mutex_unlock(&ci->i_fragtree_mutex);
+	return err;
+}
+
+
+/*
+ * 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(10, "alloc_inode %p\n", &ci->vfs_inode);
+
+	ci->i_version = 0;
+	ci->i_time_warp_seq = 0;
+	ci->i_ceph_flags = 0;
+	ci->i_release_count = 0;
+	ci->i_symlink = NULL;
+
+	ci->i_fragtree = RB_ROOT;
+	mutex_init(&ci->i_fragtree_mutex);
+
+	ci->i_xattrs.xattrs = RB_ROOT;
+	ci->i_xattrs.len = 0;
+	ci->i_xattrs.version = 0;
+	ci->i_xattrs.index_version = 0;
+	ci->i_xattrs.data = NULL;
+	ci->i_xattrs.count = 0;
+	ci->i_xattrs.names_size = 0;
+	ci->i_xattrs.vals_size = 0;
+	ci->i_xattrs.prealloc_blob = NULL;
+	ci->i_xattrs.prealloc_size = 0;
+	ci->i_xattrs.dirty = 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_sync_item);
+	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);
+	ci->i_cap_exporting_mds = 0;
+	ci->i_cap_exporting_mseq = 0;
+	ci->i_cap_exporting_issued = 0;
+	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;
+
+	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_wrbuffer_ref = 0;
+	ci->i_wrbuffer_ref_head = 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_inode_writeback);
+	INIT_WORK(&ci->i_pg_inv_work, ceph_inode_invalidate_pages);
+
+	INIT_WORK(&ci->i_vmtruncate_work, ceph_vmtruncate_work);
+
+	return &ci->vfs_inode;
+}
+
+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(30, "destroy_inode %p ino %llx.%llx\n", inode, ceph_vinop(inode));
+
+	ceph_queue_caps_release(inode);
+
+	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);
+	}
+	kfree(ci->i_xattrs.data);
+	__destroy_xattrs(ci);
+	kmem_cache_free(ceph_inode_cachep, ci);
+}
+
+
+/*
+ * 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 on the MDS.
+ */
+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(10, "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(10, "truncate_seq %u -> %u\n",
+			     ci->i_truncate_seq, truncate_seq);
+			ci->i_truncate_seq = truncate_seq;
+			if (issued & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_RD|
+				      CEPH_CAP_FILE_WR|CEPH_CAP_FILE_BUFFER|
+				      CEPH_CAP_FILE_EXCL)) {
+				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(10, "truncate_size %lld -> %llu\n", ci->i_truncate_size,
+		     truncate_size);
+		ci->i_truncate_size = truncate_size;
+	}
+	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)) {
+		if (timespec_compare(ctime, &inode->i_ctime) > 0) {
+			dout(20, "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(20, "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(20, "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(20, "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 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(10, "%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 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_reply_inode *info = iinfo->in;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int i;
+	int issued, implemented;
+	struct timespec mtime, atime, ctime;
+	u32 nsplits;
+	void *xattr_data = NULL;
+	int err = 0;
+	int queue_trunc = 0;
+
+	dout(30, "fill_inode %p ino %llx.%llx v %llu had %llu\n",
+	     inode, ceph_vinop(inode), le64_to_cpu(info->version),
+	     ci->i_version);
+
+	/*
+	 * 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 && iinfo->xattr_len != ci->i_xattrs.len) {
+		xattr_data = kmalloc(iinfo->xattr_len, GFP_NOFS);
+		if (!xattr_data)
+			derr(10, "ENOMEM on xattr blob %d bytes\n",
+			     ci->i_xattrs.len);
+	}
+
+	spin_lock(&inode->i_lock);
+
+	/*
+	 * provided version will be odd if inode value is projected,
+	 * even if stable.  skip the update if we have a newer info
+	 * (e.g., due to inode info racing form multiple MDSs), or if
+	 * we are getting projected (unstable) inode info.
+	 */
+	if (le64_to_cpu(info->version) > 0 &&
+	    (ci->i_version & ~1) > le64_to_cpu(info->version))
+		goto no_change;
+
+	issued = __ceph_caps_issued(ci, &implemented);
+	issued |= implemented | __ceph_caps_dirty(ci);
+
+	/* update inode */
+	ci->i_version = le64_to_cpu(info->version);
+	inode->i_version++;
+	inode->i_rdev = le32_to_cpu(info->rdev);
+
+	if ((issued & CEPH_CAP_AUTH_EXCL) == 0) {
+		inode->i_mode = le32_to_cpu(info->mode);
+		inode->i_uid = le32_to_cpu(info->uid);
+		inode->i_gid = le32_to_cpu(info->gid);
+		dout(20, "%p mode 0%o uid.gid %d.%d\n", inode, inode->i_mode,
+		     inode->i_uid, inode->i_gid);
+	}
+
+	if ((issued & CEPH_CAP_LINK_EXCL) == 0)
+		inode->i_nlink = le32_to_cpu(info->nlink);
+
+	/* be careful with mtime, atime, size */
+	ceph_decode_timespec(&atime, &info->atime);
+	ceph_decode_timespec(&mtime, &info->mtime);
+	ceph_decode_timespec(&ctime, &info->ctime);
+	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));
+	ceph_fill_file_time(inode, issued,
+			    le32_to_cpu(info->time_warp_seq),
+			    &ctime, &mtime, &atime);
+
+	ci->i_max_size = le64_to_cpu(info->max_size);
+	ci->i_layout = info->layout;
+	inode->i_blkbits = fls(le32_to_cpu(info->layout.fl_stripe_unit)) - 1;
+
+	/* xattrs */
+	/* note that if i_xattrs.len <= 4, i_xattrs.data will still be NULL. */
+	if (iinfo->xattr_len && (issued & CEPH_CAP_XATTR_EXCL) == 0 &&
+	    le64_to_cpu(info->xattr_version) > ci->i_xattrs.version) {
+		if (ci->i_xattrs.len != iinfo->xattr_len) {
+			kfree(ci->i_xattrs.data);
+			ci->i_xattrs.len = iinfo->xattr_len;
+			ci->i_xattrs.version = le64_to_cpu(info->xattr_version);
+			ci->i_xattrs.data = xattr_data;
+			xattr_data = NULL;
+		}
+		if (ci->i_xattrs.len > 4)
+			memcpy(ci->i_xattrs.data, iinfo->xattr_data,
+			       ci->i_xattrs.len);
+	}
+
+	inode->i_mapping->a_ops = &ceph_aops;
+	inode->i_mapping->backing_dev_info =
+		&ceph_client(inode->i_sb)->backing_dev_info;
+
+no_change:
+	spin_unlock(&inode->i_lock);
+
+	/* queue truncate if we saw i_size decrease */
+	if (queue_trunc)
+		if (queue_work(ceph_client(inode->i_sb)->trunc_wq,
+			       &ci->i_vmtruncate_work))
+			igrab(inode);
+
+	/* populate frag tree */
+	/* FIXME: move me up, if/when version reflects fragtree changes */
+	nsplits = le32_to_cpu(info->fragtree.nsplits);
+	mutex_lock(&ci->i_fragtree_mutex);
+	for (i = 0; i < nsplits; i++) {
+		u32 id = le32_to_cpu(info->fragtree.splits[i].frag);
+		struct ceph_inode_frag *frag = __get_or_create_frag(ci, id);
+
+		if (IS_ERR(frag))
+			continue;
+		frag->split_by = le32_to_cpu(info->fragtree.splits[i].by);
+		dout(20, " frag %x split by %d\n", frag->frag, frag->split_by);
+	}
+	mutex_unlock(&ci->i_fragtree_mutex);
+
+	/* were we issued a capability? */
+	if (info->cap.caps) {
+		if (ceph_snap(inode) == CEPH_NOSNAP) {
+			ceph_add_cap(inode, session,
+				     le64_to_cpu(info->cap.cap_id),
+				     cap_fmode,
+				     le32_to_cpu(info->cap.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),
+				     le32_to_cpu(info->cap.ttl_ms),
+				     ttl_from,
+				     info->cap.flags,
+				     caps_reservation);
+		} else {
+			spin_lock(&inode->i_lock);
+			dout(20, " %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);
+			spin_unlock(&inode->i_lock);
+		}
+	}
+
+	/* update delegation info? */
+	if (dirinfo)
+		ceph_fill_dirfrag(inode, dirinfo);
+
+	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) {
+			int symlen = iinfo->symlink_len;
+
+			BUG_ON(symlen != inode->i_size);
+			err = -ENOMEM;
+			ci->i_symlink = kmalloc(symlen+1, GFP_NOFS);
+			if (!ci->i_symlink)
+				goto out;
+			memcpy(ci->i_symlink, iinfo->symlink, symlen);
+			ci->i_symlink[symlen] = 0;
+		}
+		break;
+	case S_IFDIR:
+		inode->i_op = &ceph_dir_iops;
+		inode->i_fop = &ceph_dir_fops;
+
+		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);
+
+		/* it may be better to set st_size in getattr instead? */
+		if (ceph_test_opt(ceph_client(inode->i_sb), RBYTES))
+			inode->i_size = ci->i_rbytes;
+
+		/* set dir completion flag? */
+		if (ci->i_files == 0 && ci->i_subdirs == 0 &&
+		    ceph_snap(inode) == CEPH_NOSNAP &&
+		    (le32_to_cpu(info->cap.caps) & CEPH_CAP_FILE_SHARED)) {
+			dout(10, " marking %p complete (empty)\n", inode);
+			ci->i_ceph_flags |= CEPH_I_COMPLETE;
+			ci->i_max_offset = 2;
+		}
+		break;
+	default:
+		derr(0, "BAD mode 0%o S_IFMT 0%o\n", inode->i_mode,
+		     inode->i_mode & S_IFMT);
+		err = -EINVAL;
+		goto out;
+	}
+	err = 0;
+
+out:
+	kfree(xattr_data);
+	return err;
+}
+
+int ceph_init_dentry_private(struct dentry *dentry)
+{
+	struct ceph_dentry_info *di;
+
+	if (dentry->d_fsdata)
+		return 0;
+
+	di = kmalloc(sizeof(struct ceph_dentry_info),
+		     GFP_NOFS);
+
+	if (!di)
+		return -ENOMEM;          /* oh well */
+
+	spin_lock(&dentry->d_lock);
+
+	if (dentry->d_fsdata) /* lost a race */
+		goto out_unlock;
+
+	di->dentry = dentry;
+	di->lease_session = NULL;
+	dentry->d_fsdata = di;
+	dentry->d_time = jiffies;
+	ceph_dentry_lru_add(dentry);
+out_unlock:
+	spin_unlock(&dentry->d_lock);
+
+	return 0;
+}
+
+/*
+ * 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(10, "update_dentry_lease %p mask %d duration %lu ms ttl %lu\n",
+	     dentry, le16_to_cpu(lease->mask), duration, ttl);
+
+	/* make lease_rdcache_gen match directory */
+	dir = dentry->d_parent->d_inode;
+	di->lease_rdcache_gen = ceph_inode(dir)->i_rdcache_gen;
+
+	if (lease->mask == 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;
+
+	/* dn must be unhashed */
+	if (!d_unhashed(dn))
+		d_drop(dn);
+	realdn = d_materialise_unique(dn, in);
+	if (IS_ERR(realdn)) {
+		derr(0, "error splicing %p (%d) inode %p ino %llx.%llx\n",
+		     dn, atomic_read(&dn->d_count), 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(10, "dn %p (%d) spliced with %p (%d) "
+		     "inode %p ino %llx.%llx\n",
+		     dn, atomic_read(&dn->d_count),
+		     realdn, atomic_read(&realdn->d_count),
+		     realdn->d_inode, ceph_vinop(realdn->d_inode));
+		dput(dn);
+		dn = realdn;
+	} else {
+		BUG_ON(!ceph_dentry(dn));
+
+		dout(10, "dn %p attached to %p ino %llx.%llx\n",
+		     dn, dn->d_inode, ceph_vinop(dn->d_inode));
+	}
+	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).
+ *
+ * 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_mds_reply_inode *ininfo;
+	struct ceph_vino vino;
+	int i = 0;
+	int err = 0;
+
+	dout(10, "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) {
+		dout(0, "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(10, "fill_trace reply is empty!\n");
+		if (rinfo->head->result == 0 && req->r_locked_dir) {
+			struct ceph_inode_info *ci =
+				ceph_inode(req->r_locked_dir);
+			dout(10, " clearing %p complete (empty trace)\n",
+			     req->r_locked_dir);
+			ci->i_ceph_flags &= ~CEPH_I_COMPLETE;
+			ci->i_release_count++;
+		}
+		return 0;
+	}
+
+	if (rinfo->head->is_dentry) {
+		/*
+		 * 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(dn->d_parent->d_inode != 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));
+
+		err = fill_inode(dir, &rinfo->diri, rinfo->dirfrag,
+				 session, req->r_request_started, -1,
+				 &req->r_caps_reservation);
+		if (err < 0)
+			return err;
+
+		/* 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 ||
+			(le16_to_cpu(rinfo->dlease->mask) &
+			 CEPH_LOCK_DN);
+
+		if (!have_lease)
+			dout(10, "fill_trace  no dentry lease or dir cap\n");
+
+		/* rename? */
+		if (req->r_old_dentry && req->r_op == CEPH_MDS_OP_RENAME) {
+			dout(10, " src %p '%.*s' dst %p '%.*s'\n",
+			     req->r_old_dentry,
+			     req->r_old_dentry->d_name.len,
+			     req->r_old_dentry->d_name.name,
+			     dn, dn->d_name.len, dn->d_name.name);
+			dout(10, "fill_trace doing d_move %p -> %p\n",
+			     req->r_old_dentry, dn);
+			d_move(req->r_old_dentry, dn);
+			dout(10, " src %p '%.*s' dst %p '%.*s'\n",
+			     req->r_old_dentry,
+			     req->r_old_dentry->d_name.len,
+			     req->r_old_dentry->d_name.name,
+			     dn, dn->d_name.len, dn->d_name.name);
+			/* take overwritten dentry's readdir offset */
+			ceph_dentry(req->r_old_dentry)->offset =
+				ceph_dentry(dn)->offset;
+			dn = req->r_old_dentry;  /* use old_dentry */
+			in = dn->d_inode;
+		}
+
+		/* null dentry? */
+		if (!rinfo->head->is_target) {
+			dout(10, "fill_trace null dentry\n");
+			if (dn->d_inode) {
+				dout(20, "d_delete %p\n", dn);
+				d_delete(dn);
+			} else {
+				dout(20, "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 */
+		ininfo = rinfo->targeti.in;
+		vino.ino = le64_to_cpu(ininfo->ino);
+		vino.snap = le64_to_cpu(ininfo->snapid);
+		if (!dn->d_inode) {
+			in = ceph_get_inode(sb, vino);
+			if (IS_ERR(in)) {
+				derr(30, "get_inode badness\n");
+				err = PTR_ERR(in);
+				d_delete(dn);
+				goto done;
+			}
+			dn = splice_dentry(dn, in, &have_lease);
+			if (IS_ERR(dn)) {
+				err = PTR_ERR(dn);
+				goto done;
+			}
+			req->r_dentry = dn;  /* may have spliced */
+			igrab(in);
+		} else if (ceph_ino(in) == vino.ino &&
+			   ceph_snap(in) == vino.snap) {
+			igrab(in);
+		} else {
+			dout(10, " %p links to %p %llx.%llx, not %llx.%llx\n",
+			     dn, in, ceph_ino(in), ceph_snap(in),
+			     vino.ino, vino.snap);
+			have_lease = false;
+			in = NULL;
+		}
+
+		if (have_lease)
+			update_dentry_lease(dn, rinfo->dlease, session,
+					    req->r_request_started);
+		dout(10, " final dn %p\n", dn);
+		i++;
+	} else if (req->r_op == CEPH_MDS_OP_LOOKUPSNAP ||
+		   req->r_op == CEPH_MDS_OP_MKSNAP) {
+		struct dentry *dn = req->r_dentry;
+
+		/* fill out a snapdir LOOKUPSNAP dentry */
+		BUG_ON(!dn);
+		BUG_ON(!req->r_locked_dir);
+		BUG_ON(ceph_snap(req->r_locked_dir) != CEPH_SNAPDIR);
+		ininfo = rinfo->targeti.in;
+		vino.ino = le64_to_cpu(ininfo->ino);
+		vino.snap = le64_to_cpu(ininfo->snapid);
+		in = ceph_get_inode(sb, vino);
+		if (IS_ERR(in)) {
+			derr(30, "get_inode badness\n");
+			err = PTR_ERR(in);
+			d_delete(dn);
+			goto done;
+		}
+		dout(10, " linking snapped dir %p to dn %p\n", in, dn);
+		dn = splice_dentry(dn, in, NULL);
+		if (IS_ERR(dn)) {
+			err = PTR_ERR(dn);
+			goto done;
+		}
+		req->r_dentry = dn;  /* may have spliced */
+		igrab(in);
+		rinfo->head->is_dentry = 1;  /* fool notrace handlers */
+	}
+
+	if (rinfo->head->is_target) {
+		vino.ino = le64_to_cpu(rinfo->targeti.in->ino);
+		vino.snap = le64_to_cpu(rinfo->targeti.in->snapid);
+
+		if (in == NULL || ceph_ino(in) != vino.ino ||
+		    ceph_snap(in) != vino.snap) {
+			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,
+				 &rinfo->targeti, NULL,
+				 session, req->r_request_started,
+				 (le32_to_cpu(rinfo->head->result) == 0) ?
+				 req->r_fmode : -1,
+				 &req->r_caps_reservation);
+		if (err < 0) {
+			derr(30, "fill_inode badness\n");
+			goto done;
+		}
+	}
+
+done:
+	dout(10, "fill_trace done err=%d\n", err);
+	return err;
+}
+
+/*
+ * prepopulate cache with readdir results, leases, etc.
+ */
+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, i;
+	struct inode *snapdir = NULL;
+	struct ceph_mds_request_head *rhead = req->r_request->front.iov_base;
+	u64 frag = le32_to_cpu(rhead->args.readdir.frag);
+	struct ceph_dentry_info *di;
+
+	if (le32_to_cpu(rinfo->head->op) == CEPH_MDS_OP_LSSNAP) {
+		snapdir = ceph_get_snapdir(parent->d_inode);
+		parent = d_find_alias(snapdir);
+		dout(10, "readdir_prepopulate %d items under SNAPDIR dn %p\n",
+		     rinfo->dir_nr, parent);
+	} else {
+		dout(10, "readdir_prepopulate %d items under dn %p\n",
+		     rinfo->dir_nr, parent);
+		if (rinfo->dir_dir)
+			ceph_fill_dirfrag(parent->d_inode, rinfo->dir_dir);
+	}
+
+	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(30, "d_lookup on parent=%p name=%.*s got %p\n",
+		     parent, dname.len, dname.name, dn);
+
+		if (!dn) {
+			dn = d_alloc(parent, &dname);
+			dout(40, "d_alloc %p '%.*s' = %p\n", parent,
+			     dname.len, dname.name, dn);
+			if (dn == NULL) {
+				dout(30, "d_alloc badness\n");
+				err = -ENOMEM;
+				goto out;
+			}
+			err = ceph_init_dentry(dn);
+			if (err < 0)
+				goto out;
+		} else if (dn->d_inode &&
+			   (ceph_ino(dn->d_inode) != vino.ino ||
+			    ceph_snap(dn->d_inode) != vino.snap)) {
+			dout(10, " dn %p points to wrong inode %p\n",
+			     dn, dn->d_inode);
+			d_delete(dn);
+			dput(dn);
+			goto retry_lookup;
+		} else {
+			/* reorder parent's d_subdirs */
+			spin_lock(&dcache_lock);
+			spin_lock(&dn->d_lock);
+			list_move(&dn->d_u.d_child, &parent->d_subdirs);
+			spin_unlock(&dn->d_lock);
+			spin_unlock(&dcache_lock);
+		}
+
+		di = dn->d_fsdata;
+		di->offset = ceph_make_fpos(frag, i + req->r_readdir_offset);
+
+		/* inode */
+		if (dn->d_inode) {
+			in = dn->d_inode;
+		} else {
+			in = ceph_get_inode(parent->d_sb, vino);
+			if (in == NULL) {
+				dout(30, "new_inode badness\n");
+				d_delete(dn);
+				dput(dn);
+				err = -ENOMEM;
+				goto out;
+			}
+			dn = splice_dentry(dn, in, NULL);
+		}
+
+		if (fill_inode(in, &rinfo->dir_in[i], NULL, session,
+			       req->r_request_started, -1,
+			       &req->r_caps_reservation) < 0) {
+			dout(0, "fill_inode badness on %p\n", in);
+			dput(dn);
+			continue;
+		}
+		update_dentry_lease(dn, rinfo->dir_dlease[i],
+				    req->r_session, req->r_request_started);
+		dput(dn);
+	}
+	req->r_did_prepopulate = true;
+
+out:
+	if (snapdir) {
+		iput(snapdir);
+		dput(parent);
+	}
+	dout(10, "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(&inode->i_lock);
+	dout(30, "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(&inode->i_lock);
+	return ret;
+}
+
+/*
+ * Write back inode data in a worker thread.  (This can't be done
+ * in the message handler context.)
+ */
+void ceph_inode_writeback(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(10, "writeback %p\n", inode);
+	filemap_fdatawrite(&inode->i_data);
+	iput(inode);
+}
+
+/*
+ * Invalidate inode pages in a worker thread.  (This can't be done
+ * in the message handler context.)
+ */
+static void ceph_inode_invalidate_pages(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;
+
+	spin_lock(&inode->i_lock);
+	dout(10, "invalidate_pages %p gen %d revoking %d\n", inode,
+	     ci->i_rdcache_gen, ci->i_rdcache_revoking);
+	if (ci->i_rdcache_gen == 0 ||
+	    ci->i_rdcache_revoking != ci->i_rdcache_gen) {
+		BUG_ON(ci->i_rdcache_revoking > ci->i_rdcache_gen);
+		/* nevermind! */
+		ci->i_rdcache_revoking = 0;
+		spin_unlock(&inode->i_lock);
+		goto out;
+	}
+	orig_gen = ci->i_rdcache_gen;
+	spin_unlock(&inode->i_lock);
+
+	truncate_inode_pages(&inode->i_data, 0);
+
+	spin_lock(&inode->i_lock);
+	if (orig_gen == ci->i_rdcache_gen) {
+		dout(10, "invalidate_pages %p gen %d successful\n", inode,
+		     ci->i_rdcache_gen);
+		ci->i_rdcache_gen = 0;
+		ci->i_rdcache_revoking = 0;
+		check = 1;
+	} else {
+		dout(10, "invalidate_pages %p gen %d raced, gen now %d\n",
+		     inode, orig_gen, ci->i_rdcache_gen);
+	}
+	spin_unlock(&inode->i_lock);
+
+	if (check)
+		ceph_check_caps(ci, 0, NULL);
+out:
+	iput(inode);
+}
+
+
+/*
+ * called by trunc_wq; take i_mutex ourselves
+ *
+ * We also truncation in a separate thread as well.
+ */
+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(10, "vmtruncate_work %p\n", inode);
+	mutex_lock(&inode->i_mutex);
+	__ceph_do_pending_vmtruncate(inode);
+	mutex_unlock(&inode->i_mutex);
+	iput(inode);
+}
+
+/*
+ * called with i_mutex held.
+ *
+ * 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, wake = 0;
+
+retry:
+	spin_lock(&inode->i_lock);
+	if (ci->i_truncate_pending == 0) {
+		dout(10, "__do_pending_vmtruncate %p none pending\n", inode);
+		spin_unlock(&inode->i_lock);
+		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(10, "__do_pending_vmtruncate %p flushing snaps first\n",
+		     inode);
+		spin_unlock(&inode->i_lock);
+		filemap_write_and_wait_range(&inode->i_data, 0,
+					     CEPH_FILE_MAX_SIZE);
+		goto retry;
+	}
+
+	to = ci->i_truncate_size;
+	wrbuffer_refs = ci->i_wrbuffer_ref;
+	dout(10, "__do_pending_vmtruncate %p (%d) to %lld\n", inode,
+	     ci->i_truncate_pending, to);
+	spin_unlock(&inode->i_lock);
+
+	truncate_inode_pages(inode->i_mapping, to);
+
+	spin_lock(&inode->i_lock);
+	ci->i_truncate_pending--;
+	if (ci->i_truncate_pending == 0)
+		wake = 1;
+	spin_unlock(&inode->i_lock);
+
+	if (wrbuffer_refs == 0)
+		ceph_check_caps(ci, CHECK_CAPS_AUTHONLY, NULL);
+	if (wake)
+		wake_up(&ci->i_cap_wq);
+}
+
+
+/*
+ * symlinks
+ */
+static void *ceph_sym_follow_link(struct dentry *dentry, struct nameidata *nd)
+{
+	struct ceph_inode_info *ci = ceph_inode(dentry->d_inode);
+	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
+ */
+int ceph_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct inode *parent_inode = dentry->d_parent->d_inode;
+	const unsigned int ia_valid = attr->ia_valid;
+	struct ceph_mds_request *req;
+	struct ceph_mds_client *mdsc = &ceph_client(dentry->d_sb)->mdsc;
+	int issued;
+	int release = 0, dirtied = 0;
+	int mask = 0;
+	int err = 0;
+	int queue_trunc = 0;
+
+	if (ceph_snap(inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	__ceph_do_pending_vmtruncate(inode);
+
+	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(&inode->i_lock);
+	issued = __ceph_caps_issued(ci, NULL);
+	dout(10, "setattr %p issued %s\n", inode, ceph_cap_string(issued));
+
+	if (ia_valid & ATTR_UID) {
+		dout(10, "setattr %p uid %d -> %d\n", inode,
+		     inode->i_uid, 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 ||
+			   attr->ia_uid != inode->i_uid) {
+			req->r_args.setattr.uid = cpu_to_le32(attr->ia_uid);
+			mask |= CEPH_SETATTR_UID;
+			release |= CEPH_CAP_AUTH_SHARED;
+		}
+	}
+	if (ia_valid & ATTR_GID) {
+		dout(10, "setattr %p gid %d -> %d\n", inode,
+		     inode->i_gid, 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 ||
+			   attr->ia_gid != inode->i_gid) {
+			req->r_args.setattr.gid = cpu_to_le32(attr->ia_gid);
+			mask |= CEPH_SETATTR_GID;
+			release |= CEPH_CAP_AUTH_SHARED;
+		}
+	}
+	if (ia_valid & ATTR_MODE) {
+		dout(10, "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) {
+			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(10, "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(10, "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(10, "setattr %p size %lld -> %lld\n", inode,
+		     inode->i_size, attr->ia_size);
+		if (attr->ia_size > CEPH_FILE_MAX_SIZE) {
+			err = -EINVAL;
+			goto out;
+		}
+		if ((issued & CEPH_CAP_FILE_EXCL) &&
+		    attr->ia_size > inode->i_size) {
+			inode->i_size = attr->ia_size;
+			if (attr->ia_size < inode->i_size) {
+				ci->i_truncate_size = attr->ia_size;
+				ci->i_truncate_pending++;
+				queue_trunc = 1;
+			}
+			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)
+		dout(10, "setattr %p ctime %ld.%ld -> %ld.%ld\n", inode,
+		     inode->i_ctime.tv_sec, inode->i_ctime.tv_nsec,
+		     attr->ia_ctime.tv_sec, attr->ia_ctime.tv_nsec);
+	if (ia_valid & ATTR_FILE)
+		dout(10, "setattr %p ATTR_FILE ... hrm!\n", inode);
+
+	if (dirtied) {
+		__ceph_mark_dirty_caps(ci, dirtied);
+		inode->i_ctime = CURRENT_TIME;
+	}
+
+	release &= issued;
+	spin_unlock(&inode->i_lock);
+
+	if (queue_trunc)
+		__ceph_do_pending_vmtruncate(inode);
+
+	if (mask) {
+		req->r_inode = igrab(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, parent_inode, req);
+	}
+	dout(10, "setattr %p result=%d (%s locally, %d remote)\n", inode, err,
+	     ceph_cap_string(dirtied), mask);
+
+	ceph_mdsc_put_request(req);
+	__ceph_do_pending_vmtruncate(inode);
+	return err;
+out:
+	spin_unlock(&inode->i_lock);
+	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, int mask)
+{
+	struct ceph_client *client = ceph_sb_to_client(inode->i_sb);
+	struct ceph_mds_client *mdsc = &client->mdsc;
+	struct ceph_mds_request *req;
+	int err;
+
+	if (ceph_snap(inode) == CEPH_SNAPDIR) {
+		dout(30, "do_getattr inode %p SNAPDIR\n", inode);
+		return 0;
+	}
+
+	dout(30, "do_getattr inode %p mask %s\n", inode, ceph_cap_string(mask));
+	if (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 = igrab(inode);
+	req->r_num_caps = 1;
+	req->r_args.getattr.mask = cpu_to_le32(mask);
+	err = ceph_mdsc_do_request(mdsc, NULL, req);
+	ceph_mdsc_put_request(req);
+	dout(20, "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 = ceph_do_getattr(inode, CEPH_CAP_AUTH_SHARED);
+
+	if (!err)
+		err = generic_permission(inode, mask, NULL);
+	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 = dentry->d_inode;
+	int err;
+
+	err = ceph_do_getattr(inode, CEPH_STAT_CAP_INODE_ALL);
+	if (!err) {
+		generic_fillattr(inode, stat);
+		stat->ino = inode->i_ino;
+		if (ceph_snap(inode) != CEPH_NOSNAP)
+			stat->dev = ceph_snap(inode);
+		else
+			stat->dev = 0;
+		if (S_ISDIR(inode->i_mode))
+			stat->blksize = 65536;
+	}
+	return err;
+}
+
+/*
+ * (virtual) xattrs
+ *
+ * These define virtual xattrs exposing the recursive directory statistics.
+ */
+struct _ceph_vir_xattr_cb {
+	char *name;
+	size_t (*getxattr_cb)(struct ceph_inode_info *ci, char *val,
+			      size_t size);
+};
+
+static size_t _ceph_vir_xattrcb_entries(struct ceph_inode_info *ci, char *val,
+					size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_files + ci->i_subdirs);
+}
+
+static size_t _ceph_vir_xattrcb_files(struct ceph_inode_info *ci, char *val,
+				      size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_files);
+}
+
+static size_t _ceph_vir_xattrcb_subdirs(struct ceph_inode_info *ci, char *val,
+					size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_subdirs);
+}
+
+static size_t _ceph_vir_xattrcb_rentries(struct ceph_inode_info *ci, char *val,
+					 size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_rfiles + ci->i_rsubdirs);
+}
+
+static size_t _ceph_vir_xattrcb_rfiles(struct ceph_inode_info *ci, char *val,
+				       size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_rfiles);
+}
+
+static size_t _ceph_vir_xattrcb_rsubdirs(struct ceph_inode_info *ci, char *val,
+					 size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_rsubdirs);
+}
+
+static size_t _ceph_vir_xattrcb_rbytes(struct ceph_inode_info *ci, char *val,
+				       size_t size)
+{
+	return snprintf(val, size, "%lld", ci->i_rbytes);
+}
+
+static size_t _ceph_vir_xattrcb_rctime(struct ceph_inode_info *ci, char *val,
+				       size_t size)
+{
+	return snprintf(val, size, "%ld.%ld", (long)ci->i_rctime.tv_sec,
+			(long)ci->i_rctime.tv_nsec);
+}
+
+static struct _ceph_vir_xattr_cb _ceph_vir_xattr_recs[] = {
+	{ "user.ceph.dir.entries", _ceph_vir_xattrcb_entries},
+	{ "user.ceph.dir.files", _ceph_vir_xattrcb_files},
+	{ "user.ceph.dir.subdirs", _ceph_vir_xattrcb_subdirs},
+	{ "user.ceph.dir.rentries", _ceph_vir_xattrcb_rentries},
+	{ "user.ceph.dir.rfiles", _ceph_vir_xattrcb_rfiles},
+	{ "user.ceph.dir.rsubdirs", _ceph_vir_xattrcb_rsubdirs},
+	{ "user.ceph.dir.rbytes", _ceph_vir_xattrcb_rbytes},
+	{ "user.ceph.dir.rctime", _ceph_vir_xattrcb_rctime},
+	{ NULL, NULL }
+};
+
+static struct _ceph_vir_xattr_cb *_ceph_match_vir_xattr(const char *name)
+{
+	struct _ceph_vir_xattr_cb *xattr_rec = _ceph_vir_xattr_recs;
+
+	do {
+		if (strcmp(xattr_rec->name, name) == 0)
+			return xattr_rec;
+		xattr_rec++;
+	} while (xattr_rec->name);
+
+	return NULL;
+}
+
+static int __set_xattr(struct ceph_inode_info *ci,
+			   const char *name, int name_len,
+			   const char *val, int val_len,
+			   int dirty,
+			   int should_free_name, int should_free_val,
+			   struct ceph_inode_xattr **newxattr)
+{
+	struct rb_node **p;
+	struct rb_node *parent = NULL;
+	struct ceph_inode_xattr *xattr = NULL;
+	int c;
+	int new = 0;
+
+	p = &ci->i_xattrs.xattrs.rb_node;
+	while (*p) {
+		parent = *p;
+		xattr = rb_entry(parent, struct ceph_inode_xattr, node);
+		c = strncmp(name, xattr->name, min(name_len, xattr->name_len));
+		if (c < 0)
+			p = &(*p)->rb_left;
+		else if (c > 0)
+			p = &(*p)->rb_right;
+		else {
+			if (name_len == xattr->name_len)
+				break;
+			else if (name_len < xattr->name_len)
+				p = &(*p)->rb_left;
+			else
+				p = &(*p)->rb_right;
+		}
+		xattr = NULL;
+	}
+
+	if (!xattr) {
+		new = 1;
+		xattr = *newxattr;
+		xattr->name = name;
+		xattr->name_len = name_len;
+		xattr->should_free_name = should_free_name;
+
+		ci->i_xattrs.count++;
+		dout(30, "__set_xattr count=%d\n", ci->i_xattrs.count);
+	} else {
+		kfree(*newxattr);
+		*newxattr = NULL;
+		if (xattr->should_free_val)
+			kfree((void *)xattr->val);
+
+		if (should_free_name) {
+			kfree((void *)name);
+			name = xattr->name;
+		}
+		ci->i_xattrs.names_size -= xattr->name_len;
+		ci->i_xattrs.vals_size -= xattr->val_len;
+	}
+	if (!xattr) {
+		derr(0, "ENOMEM on %p %llx.%llx xattr %s=%s\n", &ci->vfs_inode,
+		     ceph_vinop(&ci->vfs_inode), name, xattr->val);
+		return -ENOMEM;
+	}
+	ci->i_xattrs.names_size += name_len;
+	ci->i_xattrs.vals_size += val_len;
+	if (val)
+		xattr->val = val;
+	else
+		xattr->val = "";
+
+	xattr->val_len = val_len;
+	xattr->dirty = dirty;
+	xattr->should_free_val = (val && should_free_val);
+
+	if (new) {
+		rb_link_node(&xattr->node, parent, p);
+		rb_insert_color(&xattr->node, &ci->i_xattrs.xattrs);
+		dout(30, "__set_xattr_val p=%p\n", p);
+	}
+
+	dout(20, "__set_xattr_val added %llx.%llx xattr %p %s=%.*s\n",
+	     ceph_vinop(&ci->vfs_inode), xattr, name, val_len, val);
+
+	return 0;
+}
+
+static struct ceph_inode_xattr *__get_xattr(struct ceph_inode_info *ci,
+			   const char *name)
+{
+	struct rb_node **p;
+	struct rb_node *parent = NULL;
+	struct ceph_inode_xattr *xattr = NULL;
+	int c;
+
+	p = &ci->i_xattrs.xattrs.rb_node;
+	while (*p) {
+		parent = *p;
+		xattr = rb_entry(parent, struct ceph_inode_xattr, node);
+		c = strncmp(name, xattr->name, xattr->name_len);
+		if (c < 0)
+			p = &(*p)->rb_left;
+		else if (c > 0)
+			p = &(*p)->rb_right;
+		else {
+			dout(20, "__get_xattr %s: found %.*s\n", name,
+			     xattr->val_len, xattr->val);
+			return xattr;
+		}
+	}
+
+	dout(20, "__get_xattr %s: not found\n", name);
+
+	return NULL;
+}
+
+static void __free_xattr(struct ceph_inode_xattr *xattr)
+{
+	BUG_ON(!xattr);
+
+	if (xattr->should_free_name)
+		kfree((void *)xattr->name);
+	if (xattr->should_free_val)
+		kfree((void *)xattr->val);
+
+	kfree(xattr);
+}
+
+static int __remove_xattr(struct ceph_inode_info *ci,
+			  struct ceph_inode_xattr *xattr)
+{
+	if (!xattr)
+		return -EOPNOTSUPP;
+
+	rb_erase(&xattr->node, &ci->i_xattrs.xattrs);
+
+	if (xattr->should_free_name)
+		kfree((void *)xattr->name);
+	if (xattr->should_free_val)
+		kfree((void *)xattr->val);
+
+	ci->i_xattrs.names_size -= xattr->name_len;
+	ci->i_xattrs.vals_size -= xattr->val_len;
+	ci->i_xattrs.count--;
+	kfree(xattr);
+
+	return 0;
+}
+
+static int __remove_xattr_by_name(struct ceph_inode_info *ci,
+			   const char *name)
+{
+	struct rb_node **p;
+	struct ceph_inode_xattr *xattr;
+	int err;
+
+	p = &ci->i_xattrs.xattrs.rb_node;
+
+	xattr = __get_xattr(ci, name);
+
+	err = __remove_xattr(ci, xattr);
+
+	return err;
+}
+
+static char *__copy_xattr_names(struct ceph_inode_info *ci,
+				char *dest)
+{
+	struct rb_node *p;
+	struct ceph_inode_xattr *xattr = NULL;
+
+	p = rb_first(&ci->i_xattrs.xattrs);
+	dout(30, "__copy_xattr_names count=%d\n", ci->i_xattrs.count);
+
+	while (p) {
+		xattr = rb_entry(p, struct ceph_inode_xattr, node);
+		memcpy(dest, xattr->name, xattr->name_len);
+		dest[xattr->name_len] = '\0';
+
+		dout(30, "dest=%s %p (%s) (%d/%d)\n", dest, xattr, xattr->name,
+		     xattr->name_len, ci->i_xattrs.names_size);
+
+		dest += xattr->name_len + 1;
+		p = rb_next(p);
+	}
+
+	return dest;
+}
+
+static void __destroy_xattrs(struct ceph_inode_info *ci)
+{
+	struct rb_node *p, *tmp;
+	struct ceph_inode_xattr *xattr = NULL;
+
+	p = rb_first(&ci->i_xattrs.xattrs);
+
+	dout(20, "__destroy_xattrs p=%p\n", p);
+
+	while (p) {
+		xattr = rb_entry(p, struct ceph_inode_xattr, node);
+		tmp = p;
+		p = rb_next(tmp);
+		dout(30, "__destroy_xattrs next p=%p (%.*s)\n", p,
+		     xattr->name_len, xattr->name);
+		rb_erase(tmp, &ci->i_xattrs.xattrs);
+
+		__free_xattr(xattr);
+	}
+
+	ci->i_xattrs.names_size = 0;
+	ci->i_xattrs.vals_size = 0;
+	ci->i_xattrs.index_version = 0;
+	ci->i_xattrs.count = 0;
+	ci->i_xattrs.xattrs = RB_ROOT;
+}
+
+static int __build_xattrs(struct inode *inode)
+{
+	u32 namelen;
+	u32 numattr = 0;
+	void *p, *end;
+	u32 len;
+	const char *name, *val;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int xattr_version;
+	struct ceph_inode_xattr **xattrs = NULL;
+	int err;
+	int i;
+
+	dout(20, "__build_xattrs(): ci->i_xattrs.len=%d\n", ci->i_xattrs.len);
+
+	if (ci->i_xattrs.index_version >= ci->i_xattrs.version)
+		return 0; /* already built */
+
+	__destroy_xattrs(ci);
+
+start:
+	/* updated internal xattr rb tree */
+	if (ci->i_xattrs.len > 4) {
+		p = ci->i_xattrs.data;
+		end = p + ci->i_xattrs.len;
+		ceph_decode_32_safe(&p, end, numattr, bad);
+		xattr_version = ci->i_xattrs.version;
+		spin_unlock(&inode->i_lock);
+
+		xattrs = kmalloc(numattr*sizeof(struct ceph_xattr *), GFP_NOFS);
+		err = -ENOMEM;
+		if (!xattrs)
+			goto bad_lock;
+		memset(xattrs, 0, numattr*sizeof(struct ceph_xattr *));
+		for (i = 0; i < numattr; i++) {
+			xattrs[i] = kmalloc(sizeof(struct ceph_inode_xattr),
+					    GFP_NOFS);
+			if (!xattrs[i])
+				goto bad_lock;
+		}
+
+		spin_lock(&inode->i_lock);
+		if (ci->i_xattrs.version != xattr_version) {
+			/* lost a race, retry */
+			for (i = 0; i < numattr; i++)
+				kfree(xattrs[i]);
+			kfree(xattrs);
+			goto start;
+		}
+		err = -EIO;
+		while (numattr--) {
+			ceph_decode_32_safe(&p, end, len, bad);
+			namelen = len;
+			name = p;
+			p += len;
+			ceph_decode_32_safe(&p, end, len, bad);
+			val = p;
+			p += len;
+
+			err = __set_xattr(ci, name, namelen, val, len,
+					  0, 0, 0, &xattrs[numattr]);
+
+			if (err < 0)
+				goto bad;
+		}
+		kfree(xattrs);
+	}
+	ci->i_xattrs.index_version = ci->i_xattrs.version;
+	ci->i_xattrs.dirty = 0;
+
+	return err;
+bad_lock:
+	spin_lock(&inode->i_lock);
+bad:
+	if (xattrs) {
+		for (i = 0; i < numattr; i++)
+			kfree(xattrs[i]);
+		kfree(xattrs);
+	}
+	ci->i_xattrs.names_size = 0;
+	return err;
+}
+
+static int __get_required_blob_size(struct ceph_inode_info *ci, int name_size,
+				    int val_size)
+{
+	/*
+	 * 4 bytes for the length, and additional 4 bytes per each xattr name,
+	 * 4 bytes per each value
+	 */
+	int size = 4 + ci->i_xattrs.count*(4 + 4) +
+			     ci->i_xattrs.names_size +
+			     ci->i_xattrs.vals_size;
+	dout(30, "__get_required_blob_size c=%d names.size=%d vals.size=%d\n",
+	     ci->i_xattrs.count, ci->i_xattrs.names_size,
+	     ci->i_xattrs.vals_size);
+
+	if (name_size)
+		size += 4 + 4 + name_size + val_size;
+
+	return size;
+}
+
+void __ceph_build_xattrs_blob(struct ceph_inode_info *ci,
+			      void **xattrs_blob,
+			      int *blob_size)
+{
+	struct rb_node *p;
+	struct ceph_inode_xattr *xattr = NULL;
+	void *dest;
+
+	if (ci->i_xattrs.dirty) {
+		int required_blob_size = __get_required_blob_size(ci, 0, 0);
+
+		BUG_ON(required_blob_size > ci->i_xattrs.prealloc_size);
+
+		p = rb_first(&ci->i_xattrs.xattrs);
+
+		dest = ci->i_xattrs.prealloc_blob;
+		ceph_encode_32(&dest, ci->i_xattrs.count);
+
+		while (p) {
+			xattr = rb_entry(p, struct ceph_inode_xattr, node);
+
+			ceph_encode_32(&dest, xattr->name_len);
+			memcpy(dest, xattr->name, xattr->name_len);
+			dest += xattr->name_len;
+			ceph_encode_32(&dest, xattr->val_len);
+			memcpy(dest, xattr->val, xattr->val_len);
+			dest += xattr->val_len;
+
+			p = rb_next(p);
+		}
+
+		*xattrs_blob =  ci->i_xattrs.prealloc_blob;
+		*blob_size = ci->i_xattrs.prealloc_size;
+	} else {
+		/* actually, we're using the same data that we got from the
+		   mds, don't build anything */
+		*xattrs_blob = NULL;
+		*blob_size = 0;
+	}
+}
+
+ssize_t ceph_getxattr(struct dentry *dentry, const char *name, void *value,
+		      size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int err;
+	struct _ceph_vir_xattr_cb *vir_xattr;
+	struct ceph_inode_xattr *xattr;
+
+	/* let's see if a virtual xattr was requested */
+	vir_xattr = _ceph_match_vir_xattr(name);
+	if (vir_xattr)
+		return (vir_xattr->getxattr_cb)(ci, value, size);
+
+	spin_lock(&inode->i_lock);
+	dout(10, "getxattr %p ver=%lld index_ver=%lld\n", inode,
+	     ci->i_xattrs.version, ci->i_xattrs.index_version);
+
+	if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
+	    (ci->i_xattrs.index_version >= ci->i_xattrs.version)) {
+		goto get_xattr;
+	} else {
+		spin_unlock(&inode->i_lock);
+		/* get xattrs from mds (if we don't already have them) */
+		err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
+		if (err)
+			return err;
+	}
+
+	spin_lock(&inode->i_lock);
+
+	err = -ENODATA;  /* == ENOATTR */
+
+	err = __build_xattrs(inode);
+	if (err < 0)
+		goto out;
+
+get_xattr:
+	err = -ENODATA;
+	xattr = __get_xattr(ci, name);
+	if (!xattr)
+		goto out;
+
+	err = -ERANGE;
+	if (size && size < xattr->val_len)
+		goto out;
+
+	err = xattr->val_len;
+	if (size == 0)
+		goto out;
+
+	memcpy(value, xattr->val, xattr->val_len);
+
+out:
+	spin_unlock(&inode->i_lock);
+	return err;
+}
+
+ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	u32 vir_namelen = 0;
+	u32 namelen;
+	int err;
+	u32 len;
+	int i;
+
+	spin_lock(&inode->i_lock);
+	dout(10, "listxattr %p ver=%lld index_ver=%lld\n", inode,
+	     ci->i_xattrs.version, ci->i_xattrs.index_version);
+
+	if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1) &&
+	    (ci->i_xattrs.index_version > ci->i_xattrs.version)) {
+		goto list_xattr;
+	} else {
+		spin_unlock(&inode->i_lock);
+		err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR);
+		if (err)
+			return err;
+	}
+
+	spin_lock(&inode->i_lock);
+
+	err = __build_xattrs(inode);
+	if (err < 0)
+		goto out;
+
+list_xattr:
+	vir_namelen = 0;
+	/* include virtual dir xattrs */
+	if ((inode->i_mode & S_IFMT) == S_IFDIR)
+		for (i = 0; _ceph_vir_xattr_recs[i].name; i++)
+			vir_namelen += strlen(_ceph_vir_xattr_recs[i].name) + 1;
+	/* adding 1 byte per each variable due to the null termination */
+	namelen = vir_namelen + ci->i_xattrs.names_size + ci->i_xattrs.count;
+	err = -ERANGE;
+	if (size && namelen > size)
+		goto out;
+
+	err = namelen;
+	if (size == 0)
+		goto out;
+
+	names = __copy_xattr_names(ci, names);
+
+	/* virtual xattr names, too */
+	if ((inode->i_mode & S_IFMT) == S_IFDIR)
+		for (i = 0; _ceph_vir_xattr_recs[i].name; i++) {
+			len = sprintf(names, "%s",
+				      _ceph_vir_xattr_recs[i].name);
+			names += len + 1;
+		}
+
+out:
+	spin_unlock(&inode->i_lock);
+	return err;
+}
+
+static int ceph_sync_setxattr(struct dentry *dentry, const char *name,
+			      const char *value, size_t size, int flags)
+{
+	struct ceph_client *client = ceph_client(dentry->d_sb);
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	struct inode *parent_inode = dentry->d_parent->d_inode;
+	struct ceph_mds_request *req;
+	struct ceph_mds_client *mdsc = &client->mdsc;
+	int err;
+	int i, nr_pages;
+	struct page **pages = NULL;
+	void *kaddr;
+
+	/* copy value into some pages */
+	nr_pages = calc_pages_for(0, size);
+	if (nr_pages) {
+		pages = kmalloc(sizeof(pages)*nr_pages, GFP_NOFS);
+		if (!pages)
+			return -ENOMEM;
+		err = -ENOMEM;
+		for (i = 0; i < nr_pages; i++) {
+			pages[i] = alloc_page(GFP_NOFS);
+			if (!pages[i]) {
+				nr_pages = i;
+				goto out;
+			}
+			kaddr = kmap(pages[i]);
+			memcpy(kaddr, value + i*PAGE_CACHE_SIZE,
+			       min(PAGE_CACHE_SIZE, size-i*PAGE_CACHE_SIZE));
+		}
+	}
+
+	dout(10, "setxattr value=%.*s\n", (int)size, value);
+
+	/* do request */
+	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SETXATTR,
+				       USE_AUTH_MDS);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	req->r_inode = igrab(inode);
+	req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
+	req->r_num_caps = 1;
+	req->r_args.setxattr.flags = cpu_to_le32(flags);
+	req->r_path2 = name;
+
+	req->r_pages = pages;
+	req->r_num_pages = nr_pages;
+	req->r_data_len = size;
+
+	dout(30, "xattr.ver (before): %lld\n", ci->i_xattrs.version);
+	err = ceph_mdsc_do_request(mdsc, parent_inode, req);
+	ceph_mdsc_put_request(req);
+	dout(30, "xattr.ver (after): %lld\n", ci->i_xattrs.version);
+
+out:
+	if (pages) {
+		for (i = 0; i < nr_pages; i++)
+			__free_page(pages[i]);
+		kfree(pages);
+	}
+	return err;
+}
+
+int ceph_setxattr(struct dentry *dentry, const char *name,
+		  const void *value, size_t size, int flags)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int err;
+	int name_len = strlen(name);
+	int val_len = size;
+	char *newname = NULL;
+	char *newval = NULL;
+	struct ceph_inode_xattr *xattr = NULL;
+	int issued;
+	int required_blob_size;
+	void *prealloc_blob = NULL;
+
+	if (ceph_snap(inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	/* only support user.* xattrs, for now */
+	if (strncmp(name, "user.", 5) != 0)
+		return -EOPNOTSUPP;
+
+	if (_ceph_match_vir_xattr(name) != NULL)
+		return -EOPNOTSUPP;
+
+	err = -ENOMEM;
+	newname = kmalloc(name_len + 1, GFP_NOFS);
+	if (!newname)
+		goto out;
+	memcpy(newname, name, name_len + 1);
+
+	if (val_len) {
+		newval = kmalloc(val_len + 1, GFP_NOFS);
+		if (!newval)
+			goto out;
+		memcpy(newval, value, val_len);
+		newval[val_len] = '\0';
+	}
+
+	xattr = kmalloc(sizeof(struct ceph_inode_xattr), GFP_NOFS);
+	if (!xattr)
+		goto out;
+
+	spin_lock(&inode->i_lock);
+retry:
+	__build_xattrs(inode);
+	issued = __ceph_caps_issued(ci, NULL);
+	if (!(issued & CEPH_CAP_XATTR_EXCL))
+		goto do_sync;
+
+	required_blob_size = __get_required_blob_size(ci, name_len, val_len);
+
+	if (required_blob_size > ci->i_xattrs.prealloc_size) {
+		int prealloc_len = required_blob_size;
+
+		spin_unlock(&inode->i_lock);
+		dout(30, " required_blob_size=%d\n", required_blob_size);
+		prealloc_blob = kmalloc(prealloc_len, GFP_NOFS);
+		if (!prealloc_blob)
+			goto out;
+		spin_lock(&inode->i_lock);
+
+		required_blob_size = __get_required_blob_size(ci, name_len,
+							      val_len);
+		if (prealloc_len < required_blob_size) {
+			/* lost a race and preallocated buffer is too small */
+			kfree(prealloc_blob);
+		} else {
+			kfree(ci->i_xattrs.prealloc_blob);
+			ci->i_xattrs.prealloc_blob = prealloc_blob;
+			ci->i_xattrs.prealloc_size = prealloc_len;
+		}
+		goto retry;
+	}
+
+	dout(20, "setxattr %p issued %s\n", inode, ceph_cap_string(issued));
+	err = __set_xattr(ci, newname, name_len, newval,
+			  val_len, 1, 1, 1, &xattr);
+	__ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
+	ci->i_xattrs.dirty = 1;
+	inode->i_ctime = CURRENT_TIME;
+	spin_unlock(&inode->i_lock);
+
+	return err;
+
+do_sync:
+	spin_unlock(&inode->i_lock);
+	err = ceph_sync_setxattr(dentry, name, value, size, flags);
+out:
+	kfree(newname);
+	kfree(newval);
+	kfree(xattr);
+	return err;
+}
+
+static int ceph_send_removexattr(struct dentry *dentry, const char *name)
+{
+	struct ceph_client *client = ceph_client(dentry->d_sb);
+	struct ceph_mds_client *mdsc = &client->mdsc;
+	struct inode *inode = dentry->d_inode;
+	struct inode *parent_inode = dentry->d_parent->d_inode;
+	struct ceph_mds_request *req;
+	int err;
+
+	req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_RMXATTR,
+				       USE_AUTH_MDS);
+	if (IS_ERR(req))
+		return PTR_ERR(req);
+	req->r_inode = igrab(inode);
+	req->r_inode_drop = CEPH_CAP_XATTR_SHARED;
+	req->r_num_caps = 1;
+	req->r_path2 = name;
+
+	err = ceph_mdsc_do_request(mdsc, parent_inode, req);
+	ceph_mdsc_put_request(req);
+	return err;
+}
+
+int ceph_removexattr(struct dentry *dentry, const char *name)
+{
+	struct inode *inode = dentry->d_inode;
+	struct ceph_inode_info *ci = ceph_inode(inode);
+	int issued;
+	int err;
+
+	if (ceph_snap(inode) != CEPH_NOSNAP)
+		return -EROFS;
+
+	/* only support user.* xattrs, for now */
+	if (strncmp(name, "user.", 5) != 0)
+		return -EOPNOTSUPP;
+
+	if (_ceph_match_vir_xattr(name) != NULL)
+		return -EOPNOTSUPP;
+
+	spin_lock(&inode->i_lock);
+	__build_xattrs(inode);
+	issued = __ceph_caps_issued(ci, NULL);
+	dout(10, "removexattr %p issued %s\n", inode, ceph_cap_string(issued));
+
+	if (!(issued & CEPH_CAP_XATTR_EXCL))
+		goto do_sync;
+
+	err = __remove_xattr_by_name(ceph_inode(inode), name);
+	__ceph_mark_dirty_caps(ci, CEPH_CAP_XATTR_EXCL);
+	ci->i_xattrs.dirty = 1;
+	inode->i_ctime = CURRENT_TIME;
+
+	spin_unlock(&inode->i_lock);
+
+	return err;
+do_sync:
+	spin_unlock(&inode->i_lock);
+	err = ceph_send_removexattr(dentry, name);
+	return err;
+}
+
-- 
1.5.6.5

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