Merge tag 'regmap-3.4' into regmap-stride

regmap: Last minute bug fix for 3.4

This is a last minute bug fix that was only just noticed since the code
path that's being exercised here is one that is fairly rarely used.  The
changelog for the change itself is extremely clear and the code itself
is obvious to inspection so should be pretty safe.

Conflicts:
	drivers/base/regmap/regmap.c (overlap between the fix and stride code)

1 files changed, 11 insertions, 15 deletions

diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c
index 90acc82046c..2f3d6f917fb 100644
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -998,6 +998,7 @@ static int scrub_setup_recheck_block(struct scrub_dev *sdev,
 			page = sblock->pagev + page_index;
 			page->logical = logical;
 			page->physical = bbio->stripes[mirror_index].physical;
+			/* for missing devices, bdev is NULL */
 			page->bdev = bbio->stripes[mirror_index].dev->bdev;
 			page->mirror_num = mirror_index + 1;
 			page->page = alloc_page(GFP_NOFS);
@@ -1042,8 +1043,16 @@ static int scrub_recheck_block(struct btrfs_fs_info *fs_info,
 		struct scrub_page *page = sblock->pagev + page_num;
 		DECLARE_COMPLETION_ONSTACK(complete);
 
+		if (page->bdev == NULL) {
+			page->io_error = 1;
+			sblock->no_io_error_seen = 0;
+			continue;
+		}
+
 		BUG_ON(!page->page);
 		bio = bio_alloc(GFP_NOFS, 1);
+		if (!bio)
+			return -EIO;
 		bio->bi_bdev = page->bdev;
 		bio->bi_sector = page->physical >> 9;
 		bio->bi_end_io = scrub_complete_bio_end_io;
@@ -1171,6 +1180,8 @@ static int scrub_repair_page_from_good_copy(struct scrub_block *sblock_bad,
 		DECLARE_COMPLETION_ONSTACK(complete);
 
 		bio = bio_alloc(GFP_NOFS, 1);
+		if (!bio)
+			return -EIO;
 		bio->bi_bdev = page_bad->bdev;
 		bio->bi_sector = page_bad->physical >> 9;
 		bio->bi_end_io = scrub_complete_bio_end_io;
@@ -1253,12 +1264,6 @@ static int scrub_checksum_data(struct scrub_block *sblock)
 	if (memcmp(csum, on_disk_csum, sdev->csum_size))
 		fail = 1;
 
-	if (fail) {
-		spin_lock(&sdev->stat_lock);
-		++sdev->stat.csum_errors;
-		spin_unlock(&sdev->stat_lock);
-	}
-
 	return fail;
 }
 
@@ -1331,15 +1336,6 @@ static int scrub_checksum_tree_block(struct scrub_block *sblock)
 	if (memcmp(calculated_csum, on_disk_csum, sdev->csum_size))
 		++crc_fail;
 
-	if (crc_fail || fail) {
-		spin_lock(&sdev->stat_lock);
-		if (crc_fail)
-			++sdev->stat.csum_errors;
-		if (fail)
-			++sdev->stat.verify_errors;
-		spin_unlock(&sdev->stat_lock);
-	}
-
 	return fail || crc_fail;
 }