Introduce function, recover_from_parities(), to recover data stripes. However this function only support RAID5 yet, but should be good enough for the scrub framework.
Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com> --- check/scrub.c | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) diff --git a/check/scrub.c b/check/scrub.c index d8182d6..c965328 100644 --- a/check/scrub.c +++ b/check/scrub.c @@ -58,6 +58,9 @@ struct scrub_full_stripe { /* Missing stripe index */ int missing_stripes[2]; + /* Has already been recovered using parities */ + unsigned int recovered:1; + struct scrub_stripe stripes[]; }; @@ -467,3 +470,49 @@ out: free(ptrs); return ret; } + +static int recovery_from_parities(struct btrfs_fs_info *fs_info, + struct btrfs_scrub_progress *scrub_ctx, + struct scrub_full_stripe *fstripe) +{ + void **ptrs; + int nr_stripes = fstripe->nr_stripes; + int corrupted = -1; + int stripe_len = BTRFS_STRIPE_LEN; + int i; + int ret; + + /* No need to recover */ + if (!fstripe->err_read_stripes && !fstripe->err_csum_dstripes) + return 0; + + /* Already recovered once, no more chance */ + if (fstripe->recovered) + return -EINVAL; + + if (fstripe->bg_type == BTRFS_BLOCK_GROUP_RAID6) { + /* Need to recover 2 stripes, not supported yet */ + error("recover data stripes for RAID6 is not support yet"); + return -ENOTTY; + } + + /* Out of repair */ + if (fstripe->err_read_stripes + fstripe->err_csum_dstripes > 1) + return -EINVAL; + + ptrs = malloc(sizeof(void *) * fstripe->nr_stripes); + if (!ptrs) + return -ENOMEM; + + /* Construct ptrs */ + for (i = 0; i < nr_stripes; i++) + ptrs[i] = fstripe->stripes[i].data; + corrupted = fstripe->missing_stripes[0]; + + /* Recover the corrupted data csum */ + ret = raid5_gen_result(nr_stripes, stripe_len, corrupted, ptrs); + + fstripe->recovered = 1; + free(ptrs); + return ret; +} -- 2.10.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html