Btrfs: fill ->last_trans for delayed inode in btrfs_fill_inode.

We need to fill inode when we found a node for it in delayed_nodes_tree.
But we did not fill the ->last_trans currently, it will cause the test
of xfstest/generic/311 fail. Scenario of the 311 is shown as below:

Problem:
	(1). test_fd = open(fname, O_RDWR|O_DIRECT)
	(2). pwrite(test_fd, buf, 4096, 0)
	(3). close(test_fd)
	(4). drop_all_caches()	<-------- "echo 3 > /proc/sys/vm/drop_caches"
	(5). test_fd = open(fname, O_RDWR|O_DIRECT)
	(6). fsync(test_fd);
				<-------- we did not get the correct log entry for the file
Reason:
	When we re-open this file in (5), we would find a node
in delayed_nodes_tree and fill the inode we are lookup with the
information. But the ->last_trans is not filled, then the fsync()
will check the ->last_trans and found it's 0 then say this inode
is already in our tree which is commited, not recording the extents
for it.

Fix:
	This patch fill the ->last_trans properly and set the
runtime_flags if needed in this situation. Then we can get the
log entries we expected after (6) and generic/311 passed.

Signed-off-by: Dongsheng Yang <yangds.fnst@cn.fujitsu.com>
Reviewed-by: Miao Xie <miaoxie@huawei.com>
Signed-off-by: Chris Mason <clm@fb.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index cde698a07d21..a2ae42720a6a 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1802,6 +1802,8 @@ int btrfs_fill_inode(struct inode *inode, u32 *rdev)
 	set_nlink(inode, btrfs_stack_inode_nlink(inode_item));
 	inode_set_bytes(inode, btrfs_stack_inode_nbytes(inode_item));
 	BTRFS_I(inode)->generation = btrfs_stack_inode_generation(inode_item);
+        BTRFS_I(inode)->last_trans = btrfs_stack_inode_transid(inode_item);
+
 	inode->i_version = btrfs_stack_inode_sequence(inode_item);
 	inode->i_rdev = 0;
 	*rdev = btrfs_stack_inode_rdev(inode_item);