1 files changed, 34 insertions, 14 deletions

diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index a3ed3c811dfa..b0eb49bb4918 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -260,6 +260,7 @@ xfs_vn_lookup(
 	struct dentry	*dentry,
 	unsigned int flags)
 {
+	struct inode *inode;
 	struct xfs_inode *cip;
 	struct xfs_name	name;
 	int		error;
@@ -269,14 +270,13 @@ xfs_vn_lookup(
 
 	xfs_dentry_to_name(&name, dentry);
 	error = xfs_lookup(XFS_I(dir), &name, &cip, NULL);
-	if (unlikely(error)) {
-		if (unlikely(error != -ENOENT))
-			return ERR_PTR(error);
-		d_add(dentry, NULL);
-		return NULL;
-	}
-
-	return d_splice_alias(VFS_I(cip), dentry);
+	if (likely(!error))
+		inode = VFS_I(cip);
+	else if (likely(error == -ENOENT))
+		inode = NULL;
+	else
+		inode = ERR_PTR(error);
+	return d_splice_alias(inode, dentry);
 }
 
 STATIC struct dentry *
@@ -855,7 +855,7 @@ xfs_setattr_size(
 	/*
 	 * Make sure that the dquots are attached to the inode.
 	 */
-	error = xfs_qm_dqattach(ip, 0);
+	error = xfs_qm_dqattach(ip);
 	if (error)
 		return error;
 
@@ -1195,6 +1195,30 @@ static const struct inode_operations xfs_inline_symlink_inode_operations = {
 	.update_time		= xfs_vn_update_time,
 };
 
+/* Figure out if this file actually supports DAX. */
+static bool
+xfs_inode_supports_dax(
+	struct xfs_inode	*ip)
+{
+	struct xfs_mount	*mp = ip->i_mount;
+
+	/* Only supported on non-reflinked files. */
+	if (!S_ISREG(VFS_I(ip)->i_mode) || xfs_is_reflink_inode(ip))
+		return false;
+
+	/* DAX mount option or DAX iflag must be set. */
+	if (!(mp->m_flags & XFS_MOUNT_DAX) &&
+	    !(ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+		return false;
+
+	/* Block size must match page size */
+	if (mp->m_sb.sb_blocksize != PAGE_SIZE)
+		return false;
+
+	/* Device has to support DAX too. */
+	return xfs_find_daxdev_for_inode(VFS_I(ip)) != NULL;
+}
+
 STATIC void
 xfs_diflags_to_iflags(
 	struct inode		*inode,
@@ -1213,11 +1237,7 @@ xfs_diflags_to_iflags(
 		inode->i_flags |= S_SYNC;
 	if (flags & XFS_DIFLAG_NOATIME)
 		inode->i_flags |= S_NOATIME;
-	if (S_ISREG(inode->i_mode) &&
-	    ip->i_mount->m_sb.sb_blocksize == PAGE_SIZE &&
-	    !xfs_is_reflink_inode(ip) &&
-	    (ip->i_mount->m_flags & XFS_MOUNT_DAX ||
-	     ip->i_d.di_flags2 & XFS_DIFLAG2_DAX))
+	if (xfs_inode_supports_dax(ip))
 		inode->i_flags |= S_DAX;
 }