61 lines
2.4 KiB
Diff
61 lines
2.4 KiB
Diff
A user reported a problem where they were getting csum errors when running a
|
|
balance and running systemd's journal. This is because systemd is awesome and
|
|
fallocate()'s its log space and writes into it. Unfortunately we assume that
|
|
when we read in all the csums for an extent that they are sequential starting at
|
|
the bytenr we care about. This obviously isn't the case for prealloc extents,
|
|
where we could have written to the middle of the prealloc extent only, which
|
|
means the csum would be for the bytenr in the middle of our range and not the
|
|
front of our range. Fix this by offsetting the new bytenr we are logging to
|
|
based on the original bytenr the csum was for. With this patch I no longer see
|
|
the csum errors I was seeing. Thanks,
|
|
|
|
Cc: stable@xxxxxxxxxxxxxxx
|
|
Reported-by: Chris Murphy <lists@xxxxxxxxxxxxxxxxx>
|
|
Signed-off-by: Josef Bacik <jbacik@xxxxxxxxxxxx>
|
|
---
|
|
fs/btrfs/relocation.c | 18 +++++++++++++++---
|
|
1 file changed, 15 insertions(+), 3 deletions(-)
|
|
|
|
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
|
|
index 5ca7ea9..b7afeaa 100644
|
|
--- a/fs/btrfs/relocation.c
|
|
+++ b/fs/btrfs/relocation.c
|
|
@@ -4472,6 +4472,7 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
|
|
struct btrfs_root *root = BTRFS_I(inode)->root;
|
|
int ret;
|
|
u64 disk_bytenr;
|
|
+ u64 new_bytenr;
|
|
LIST_HEAD(list);
|
|
|
|
ordered = btrfs_lookup_ordered_extent(inode, file_pos);
|
|
@@ -4483,13 +4484,24 @@ int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
|
|
if (ret)
|
|
goto out;
|
|
|
|
- disk_bytenr = ordered->start;
|
|
while (!list_empty(&list)) {
|
|
sums = list_entry(list.next, struct btrfs_ordered_sum, list);
|
|
list_del_init(&sums->list);
|
|
|
|
- sums->bytenr = disk_bytenr;
|
|
- disk_bytenr += sums->len;
|
|
+ /*
|
|
+ * We need to offset the new_bytenr based on where the csum is.
|
|
+ * We need to do this because we will read in entire prealloc
|
|
+ * extents but we may have written to say the middle of the
|
|
+ * prealloc extent, so we need to make sure the csum goes with
|
|
+ * the right disk offset.
|
|
+ *
|
|
+ * We can do this because the data reloc inode refers strictly
|
|
+ * to the on disk bytes, so we don't have to worry about
|
|
+ * disk_len vs real len like with real inodes since it's all
|
|
+ * disk length.
|
|
+ */
|
|
+ new_bytenr = ordered->start + (sums->bytenr - disk_bytenr);
|
|
+ sums->bytenr = new_bytenr;
|
|
|
|
btrfs_add_ordered_sum(inode, ordered, sums);
|
|
}
|
|
--
|
|
1.8.3.1
|