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| author | Howard McLauchlan | 2018-02-02 20:09:01 +0100 |
|---|---|---|
| committer | David Sterba | 2018-03-26 15:09:29 +0200 |
| commit | b6a535faed06c2bdfaf55b00025dfdcb1eadf980 (patch) | |
| tree | dab689f8d38fb490352bd0dbe60a4cd5c94f58b2 /fs | |
| parent | btrfs: Refactor parameter of BTRFS_MAX_DEVS() from root to fs_info (diff) | |
| download | kernel-qcow2-linux-b6a535faed06c2bdfaf55b00025dfdcb1eadf980.tar.gz kernel-qcow2-linux-b6a535faed06c2bdfaf55b00025dfdcb1eadf980.tar.xz kernel-qcow2-linux-b6a535faed06c2bdfaf55b00025dfdcb1eadf980.zip | |
btrfs: print error if primary super block write fails
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>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/disk-io.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 21f34ad0d411..9f7ed4390b33 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -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; } |