Btrfs: Fix variables set but not read (bugs found by gcc 4.6)

These are all the cases where a variable is set, but not
read which are really bugs.

- Couple of incorrect error handling fixed.
- One incorrect use of a allocation policy
- Some other things

Still needs more review.

Found by gcc 4.6's new warnings.

[akpm@linux-foundation.org: fix build.  Might have been bitrot]
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 4c639e156296..7dc31c39ca59 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2779,6 +2779,8 @@ int extent_prepare_write(struct extent_io_tree *tree,
                                          NULL, 1,
                                          end_bio_extent_preparewrite, 0,
                                          0, 0);
+                        if (ret && !err)
+                                err = ret;
                         iocount++;
                         block_start = block_start + iosize;
                 } else {