From: Yu Kuai <yukuai3@huawei.com> mainline inclusion from mainline-v6.9-rc1 commit f29841ff3b272e1703454f93b96baf0fe0d9f31a category: bugfix bugzilla: 190197 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- The checking and handler of bad blocks appear many timers during read_balance() in raid1 and raid10. This helper will be used in later patches to simplify read_balance() a lot. Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com> Signed-off-by: Yu Kuai <yukuai3@huawei.com> Reviewed-by: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <song@kernel.org> Link: https://lore.kernel.org/r/20240229095714.926789-6-yukuai1@huaweicloud.com Signed-off-by: Li Nan <linan122@huawei.com> --- drivers/md/raid1-10.c | 49 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/drivers/md/raid1-10.c b/drivers/md/raid1-10.c index 512746551f36..9bc0f0022a6c 100644 --- a/drivers/md/raid1-10.c +++ b/drivers/md/raid1-10.c @@ -227,3 +227,52 @@ static inline bool exceed_read_errors(struct mddev *mddev, struct md_rdev *rdev) return false; } + +/** + * raid1_check_read_range() - check a given read range for bad blocks, + * available read length is returned; + * @rdev: the rdev to read; + * @this_sector: read position; + * @len: read length; + * + * helper function for read_balance() + * + * 1) If there are no bad blocks in the range, @len is returned; + * 2) If the range are all bad blocks, 0 is returned; + * 3) If there are partial bad blocks: + * - If the bad block range starts after @this_sector, the length of first + * good region is returned; + * - If the bad block range starts before @this_sector, 0 is returned and + * the @len is updated to the offset into the region before we get to the + * good blocks; + */ +static inline int raid1_check_read_range(struct md_rdev *rdev, + sector_t this_sector, int *len) +{ + sector_t first_bad; + int bad_sectors; + + /* no bad block overlap */ + if (!is_badblock(rdev, this_sector, *len, &first_bad, &bad_sectors)) + return *len; + + /* + * bad block range starts offset into our range so we can return the + * number of sectors before the bad blocks start. + */ + if (first_bad > this_sector) + return first_bad - this_sector; + + /* read range is fully consumed by bad blocks. */ + if (this_sector + *len <= first_bad + bad_sectors) + return 0; + + /* + * final case, bad block range starts before or at the start of our + * range but does not cover our entire range so we still return 0 but + * update the length with the number of sectors before we get to the + * good ones. + */ + *len = first_bad + bad_sectors - this_sector; + return 0; +} -- 2.39.2