Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-28 07:01:32 +00:00
Code Issues Packages Projects Releases Wiki Activity

btrfs: print error if primary super block write fails

Browse Source 
Presently, failing a primary super block write but succeeding in at
least one super block write in general will appear to users as if
nothing important went wrong. However, upon unmounting and re-mounting,
the file system will be in a rolled back state. This was discovered
with a BCC program that uses bpf_override_return() to fail super block
writes.

This patch outputs an error clarifying that the primary super block
write has failed, so users can expect potentially erroneous behaviour.
It also forces wait_dev_supers() to return an error to its caller if
the primary super block write fails.

Signed-off-by: Howard McLauchlan <hmclauchlan@fb.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Howard McLauchlan 2018-02-02 11:09:01 -08:00 committed by David Sterba
parent 062d4d1f40
commit b6a535faed
1 changed files with 14 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
fs/btrfs/disk-io.c
View File

@ -3290,6 +3290,7 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
struct buffer_head *bh;
int i;
int errors = 0;
bool primary_failed = false;
u64 bytenr;
if (max_mirrors == 0)
@ -3306,11 +3307,16 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
BTRFS_SUPER_INFO_SIZE);
if (!bh) {
errors++;
if (i == 0)
primary_failed = true;
continue;
}
wait_on_buffer(bh);
if (!buffer_uptodate(bh))
if (!buffer_uptodate(bh)) {
errors++;
if (i == 0)
primary_failed = true;
}
/* drop our reference */
brelse(bh);
@ -3319,6 +3325,13 @@ static int wait_dev_supers(struct btrfs_device *device, int max_mirrors)
brelse(bh);
}
/* log error, force error return */
if (primary_failed) {
btrfs_err(device->fs_info, "error writing primary super block to device %llu",
device->devid);
return -1;
}
return errors < i ? 0 : -1;
}