Added the BTRFS_FS_CHECK_INTEGRITY option to Kconfig. It depends on BTRFS_FS.
Signed-off-by: Stefan Behrens <[email protected]> --- fs/btrfs/Kconfig | 33 +++++++++++++++++++++++++++++++++ 1 files changed, 33 insertions(+), 0 deletions(-) diff --git a/fs/btrfs/Kconfig b/fs/btrfs/Kconfig index ecb9fd3..2bb8ba7 100644 --- a/fs/btrfs/Kconfig +++ b/fs/btrfs/Kconfig @@ -31,3 +31,36 @@ config BTRFS_FS_POSIX_ACL Linux website <http://acl.bestbits.at/>. If you don't know what Access Control Lists are, say N + +config BTRFS_FS_CHECK_INTEGRITY + bool "Btrfs with integrity check tool compiled in (DANGEROUS)" + depends on BTRFS_FS + help + Adds code that examines all block write requests (including + writes of the super block). The goal is to verify that the + state of the filesystem on disk is always consistent, i.e., + after a power-loss or kernel panic event the filesystem is + in a consistent state. In order to check this, three rules + are verified: + 1. It is not allowed to write a disk block which is + currently referenced by the super block (either directly + or indirectly). + 2. When a super block is written, it is verified that all + referenced (directly or indirectly) blocks fulfill the + following requirements: + 2a. All referenced blocks have either been present when + the file system was mounted, (i.e., they have been + referenced by the super block) or they have been + written since then and the write completion callback + was called. + 2b. All referenced blocks need to have a generation + number which is equal to the parent's number. + + If the integrity check tool is included and activated in + the mount options, plenty of kernel memory is used, and + plenty of additional CPU cycles are spent. Enabling this + functionality is not intended for normal use. + + In most cases, unless you are a btrfs developer who needs + to verify the integrity of (super)-block write requests + during the run of a regression test, say N -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
