On 04/11/12 21:09, Chris Samuel wrote:
That said, there's been a lot of work done trying to catch issues which could leave the filesystem in an inconsistent state on loss of power (which was the most recent corruption issue I've noticed reported), which kernel version are you thinking of?
I take that back, the following 2 patches merged for 3.7 address potential filesystem corruption issues: commit 5af3e8cce8b7ba0a2819e18c9146c8c0b452d479 Author: Stefan Behrens <sbehrens@giantdisaster.de> Date: Wed Aug 1 18:56:49 2012 +0200 Btrfs: make filesystem read-only when submitting barrier fails So far the return code of barrier_all_devices() is ignored, which means that errors are ignored. The result can be a corrupt filesystem which is not consistent. This commit adds code to evaluate the return code of barrier_all_devices(). The normal btrfs_error() mechanism is used to switch the filesystem into read-only mode when errors are detected. In order to decide whether barrier_all_devices() should return error or success, the number of disks that are allowed to fail the barrier submission is calculated. This calculation accounts for the worst RAID level of metadata, system and data. If single, dup or RAID0 is in use, a single disk error is already considered to be fatal. Otherwise a single disk error is tolerated. The calculation of the number of disks that are tolerated to fail the barrier operation is performed when the filesystem gets mounted, when a balance operation is started and finished, and when devices are added or removed. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> commit 62856a9b73860cffe2a3d91b069393b88c219aa6 Author: Stefan Behrens <sbehrens@giantdisaster.de> Date: Tue Jul 31 11:09:44 2012 -0600 Btrfs: detect corrupted filesystem after write I/O errors In check-integrity, detect when a superblock is written that points to blocks that have not been written to disk due to I/O write errors. Signed-off-by: Stefan Behrens <sbehrens@giantdisaster.de> -- Chris Samuel : http://www.csamuel.org/ : Melbourne, VIC