From: Stefan Roesch <shr@devkernel.io> mainline inclusion from mainline-v6.2-rc1 commit c354d9268d7825eb8643f658c5091079d4f11a4a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAN96I Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- This documents the new /sys/class/bdi/<bdi>/max_bytes knob. Link: https://lkml.kernel.org/r/20221119005215.3052436-10-shr@devkernel.io Signed-off-by: Stefan Roesch <shr@devkernel.io> Cc: Chris Mason <clm@meta.com> Cc: Jens Axboe <axboe@kernel.dk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- Documentation/ABI/testing/sysfs-class-bdi | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-bdi b/Documentation/ABI/testing/sysfs-class-bdi index 9982fd0439ae..726c2e2c15cf 100644 --- a/Documentation/ABI/testing/sysfs-class-bdi +++ b/Documentation/ABI/testing/sysfs-class-bdi @@ -49,6 +49,20 @@ max_ratio (read-write) be trusted to play fair. (read-write) + +What: /sys/class/bdi/<bdi>/max_bytes +Date: October 2022 +Contact: Stefan Roesch <shr@devkernel.io> +Description: + Allows limiting a particular device to use not more than the + given 'max_bytes' of the write-back cache. This is useful in + situations where we want to avoid one device taking all or + most of the write-back cache. For example in case of an NFS + mount that is prone to get stuck, a FUSE mount which cannot be + trusted to play fair, or a nbd device. + + (read-write) + What: /sys/class/bdi/<bdi>/strict_limit Date: October 2022 Contact: Stefan Roesch <shr@devkernel.io> -- 2.39.2