Commit 13db62b7 authored by Jan Schmidt's avatar Jan Schmidt
Browse files

btrfs scrub: added unverified_errors 



In normal operation, scrub is reading data sequentially in large portions.
In case of an i/o error, we try to find the corrupted area(s) by issuing
page sized read requests. With this commit we increment the
unverified_errors counter if all of the small size requests succeed.

Userland patches carrying such conspicous events to the administrator should
already be around.

Signed-off-by: default avatarJan Schmidt <list.btrfs@jan-o-sch.net>
parent a542ad1b

fs/btrfs/scrub.c

+26 −11
Original line number Diff line number Diff line
@@ -201,18 +201,25 @@ nomem: 
 * recheck_error gets called for every page in the bio, even though only

 * one may be bad

 */

static void scrub_recheck_error(struct scrub_bio *sbio, int ix)

static int scrub_recheck_error(struct scrub_bio *sbio, int ix)

{

	struct scrub_dev *sdev = sbio->sdev;

	u64 sector = (sbio->physical + ix * PAGE_SIZE) >> 9;



	if (sbio->err) {

		if (scrub_fixup_io(READ, sbio->sdev->dev->bdev,

				   (sbio->physical + ix * PAGE_SIZE) >> 9,

		if (scrub_fixup_io(READ, sbio->sdev->dev->bdev, sector,

				   sbio->bio->bi_io_vec[ix].bv_page) == 0) {

			if (scrub_fixup_check(sbio, ix) == 0)

				return;

				return 0;

		}

	}



	spin_lock(&sdev->stat_lock);

	++sdev->stat.read_errors;

	spin_unlock(&sdev->stat_lock);



	scrub_fixup(sbio, ix);

	return 1;

}



static int scrub_fixup_check(struct scrub_bio *sbio, int ix)
@@ -382,8 +389,14 @@ static void scrub_checksum(struct btrfs_work *work) 
	int ret;



	if (sbio->err) {

		ret = 0;

		for (i = 0; i < sbio->count; ++i)

			scrub_recheck_error(sbio, i);

			ret |= scrub_recheck_error(sbio, i);

		if (!ret) {

			spin_lock(&sdev->stat_lock);

			++sdev->stat.unverified_errors;

			spin_unlock(&sdev->stat_lock);

		}



		sbio->bio->bi_flags &= ~(BIO_POOL_MASK - 1);

		sbio->bio->bi_flags |= 1 << BIO_UPTODATE;
@@ -396,10 +409,6 @@ static void scrub_checksum(struct btrfs_work *work) 
			bi->bv_offset = 0;

			bi->bv_len = PAGE_SIZE;

		}



		spin_lock(&sdev->stat_lock);

		++sdev->stat.read_errors;

		spin_unlock(&sdev->stat_lock);

		goto out;

	}

	for (i = 0; i < sbio->count; ++i) {
@@ -420,8 +429,14 @@ static void scrub_checksum(struct btrfs_work *work) 
			WARN_ON(1);

		}

		kunmap_atomic(buffer, KM_USER0);

		if (ret)

			scrub_recheck_error(sbio, i);

		if (ret) {

			ret = scrub_recheck_error(sbio, i);

			if (!ret) {

				spin_lock(&sdev->stat_lock);

				++sdev->stat.unverified_errors;

				spin_unlock(&sdev->stat_lock);

			}

		}

	}



out:

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