4 files changed, 29 insertions, 52 deletions

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index 1824f61621a2..224649a76cbb 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -50,7 +50,7 @@ STATIC int xfs_attr_shortform_addname(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_get(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_removename(xfs_da_args_t *args);
 STATIC int xfs_attr_leaf_hasname(struct xfs_da_args *args, struct xfs_buf **bp);
-STATIC int xfs_attr_leaf_try_add(struct xfs_da_args *args, struct xfs_buf *bp);
+STATIC int xfs_attr_leaf_try_add(struct xfs_da_args *args);
 
 /*
  * Internal routines when attribute list is more than one block.
@@ -393,16 +393,10 @@ xfs_attr_sf_addname(
 	 * It won't fit in the shortform, transform to a leaf block.  GROT:
 	 * another possible req'mt for a double-split btree op.
 	 */
-	error = xfs_attr_shortform_to_leaf(args, &attr->xattri_leaf_bp);
+	error = xfs_attr_shortform_to_leaf(args);
 	if (error)
 		return error;
 
-	/*
-	 * Prevent the leaf buffer from being unlocked so that a concurrent AIL
-	 * push cannot grab the half-baked leaf buffer and run into problems
-	 * with the write verifier.
-	 */
-	xfs_trans_bhold(args->trans, attr->xattri_leaf_bp);
 	attr->xattri_dela_state = XFS_DAS_LEAF_ADD;
 out:
 	trace_xfs_attr_sf_addname_return(attr->xattri_dela_state, args->dp);
@@ -447,11 +441,9 @@ xfs_attr_leaf_addname(
 
 	/*
 	 * Use the leaf buffer we may already hold locked as a result of
-	 * a sf-to-leaf conversion. The held buffer is no longer valid
-	 * after this call, regardless of the result.
+	 * a sf-to-leaf conversion.
 	 */
-	error = xfs_attr_leaf_try_add(args, attr->xattri_leaf_bp);
-	attr->xattri_leaf_bp = NULL;
+	error = xfs_attr_leaf_try_add(args);
 
 	if (error == -ENOSPC) {
 		error = xfs_attr3_leaf_to_node(args);
@@ -497,8 +489,6 @@ xfs_attr_node_addname(
 	struct xfs_da_args	*args = attr->xattri_da_args;
 	int			error;
 
-	ASSERT(!attr->xattri_leaf_bp);
-
 	error = xfs_attr_node_addname_find_attr(attr);
 	if (error)
 		return error;
@@ -1215,24 +1205,14 @@ xfs_attr_restore_rmt_blk(
  */
 STATIC int
 xfs_attr_leaf_try_add(
-	struct xfs_da_args	*args,
-	struct xfs_buf		*bp)
+	struct xfs_da_args	*args)
 {
+	struct xfs_buf		*bp;
 	int			error;
 
-	/*
-	 * If the caller provided a buffer to us, it is locked and held in
-	 * the transaction because it just did a shortform to leaf conversion.
-	 * Hence we don't need to read it again. Otherwise read in the leaf
-	 * buffer.
-	 */
-	if (bp) {
-		xfs_trans_bhold_release(args->trans, bp);
-	} else {
-		error = xfs_attr3_leaf_read(args->trans, args->dp, 0, &bp);
-		if (error)
-			return error;
-	}
+	error = xfs_attr3_leaf_read(args->trans, args->dp, 0, &bp);
+	if (error)
+		return error;
 
 	/*
 	 * Look up the xattr name to set the insertion point for the new xattr.
diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index b4a2fc77017e..dfb47fa63c6d 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -515,11 +515,6 @@ struct xfs_attr_intent {
 	 */
 	struct xfs_attri_log_nameval	*xattri_nameval;
 
-	/*
-	 * Used by xfs_attr_set to hold a leaf buffer across a transaction roll
-	 */
-	struct xfs_buf			*xattri_leaf_bp;
-
 	/* Used to keep track of current state of delayed operation */
 	enum xfs_delattr_state		xattri_dela_state;
 
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 37e7c33f6283..8f47396f8dd2 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -289,6 +289,23 @@ xfs_attr3_leaf_verify_entry(
 	return NULL;
 }
 
+/*
+ * Validate an attribute leaf block.
+ *
+ * Empty leaf blocks can occur under the following circumstances:
+ *
+ * 1. setxattr adds a new extended attribute to a file;
+ * 2. The file has zero existing attributes;
+ * 3. The attribute is too large to fit in the attribute fork;
+ * 4. The attribute is small enough to fit in a leaf block;
+ * 5. A log flush occurs after committing the transaction that creates
+ *    the (empty) leaf block; and
+ * 6. The filesystem goes down after the log flush but before the new
+ *    attribute can be committed to the leaf block.
+ *
+ * Hence we need to ensure that we don't fail the validation purely
+ * because the leaf is empty.
+ */
 static xfs_failaddr_t
 xfs_attr3_leaf_verify(
 	struct xfs_buf			*bp)
@@ -311,15 +328,6 @@ xfs_attr3_leaf_verify(
 		return fa;
 
 	/*
-	 * Empty leaf blocks should never occur;  they imply the existence of a
-	 * software bug that needs fixing. xfs_repair also flags them as a
-	 * corruption that needs fixing, so we should never let these go to
-	 * disk.
-	 */
-	if (ichdr.count == 0)
-		return __this_address;
-
-	/*
 	 * firstused is the block offset of the first name info structure.
 	 * Make sure it doesn't go off the block or crash into the header.
 	 */
@@ -922,14 +930,10 @@ xfs_attr_shortform_getvalue(
 	return -ENOATTR;
 }
 
-/*
- * Convert from using the shortform to the leaf.  On success, return the
- * buffer so that we can keep it locked until we're totally done with it.
- */
+/* Convert from using the shortform to the leaf format. */
 int
 xfs_attr_shortform_to_leaf(
-	struct xfs_da_args		*args,
-	struct xfs_buf			**leaf_bp)
+	struct xfs_da_args		*args)
 {
 	struct xfs_inode		*dp;
 	struct xfs_attr_shortform	*sf;
@@ -991,7 +995,6 @@ xfs_attr_shortform_to_leaf(
 		sfe = xfs_attr_sf_nextentry(sfe);
 	}
 	error = 0;
-	*leaf_bp = bp;
 out:
 	kmem_free(tmpbuffer);
 	return error;
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
index efa757f1e912..368f4d9fa1d5 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.h
+++ b/fs/xfs/libxfs/xfs_attr_leaf.h
@@ -49,8 +49,7 @@ void	xfs_attr_shortform_create(struct xfs_da_args *args);
 void	xfs_attr_shortform_add(struct xfs_da_args *args, int forkoff);
 int	xfs_attr_shortform_lookup(struct xfs_da_args *args);
 int	xfs_attr_shortform_getvalue(struct xfs_da_args *args);
-int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args,
-			struct xfs_buf **leaf_bp);
+int	xfs_attr_shortform_to_leaf(struct xfs_da_args *args);
 int	xfs_attr_sf_removename(struct xfs_da_args *args);
 int	xfs_attr_sf_findname(struct xfs_da_args *args,
 			     struct xfs_attr_sf_entry **sfep,