3 files changed, 32 insertions, 20 deletions

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index 95a4ca6ce6ff..849ad441cd76 100644
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -760,7 +760,8 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
 	if (!d->nr_stripes ||
 	    d->nr_stripes > INT_MAX ||
 	    d->nr_stripes > SIZE_MAX / sizeof(atomic_t)) {
-		pr_err("nr_stripes too large");
+		pr_err("nr_stripes too large or invalid: %u (start sector beyond end of disk?)",
+			(unsigned)d->nr_stripes);
 		return -ENOMEM;
 	}
 
@@ -1820,7 +1821,7 @@ static int cache_alloc(struct cache *ca)
 	free = roundup_pow_of_two(ca->sb.nbuckets) >> 10;
 
 	if (!init_fifo(&ca->free[RESERVE_BTREE], 8, GFP_KERNEL) ||
-	    !init_fifo(&ca->free[RESERVE_PRIO], prio_buckets(ca), GFP_KERNEL) ||
+	    !init_fifo_exact(&ca->free[RESERVE_PRIO], prio_buckets(ca), GFP_KERNEL) ||
 	    !init_fifo(&ca->free[RESERVE_MOVINGGC], free, GFP_KERNEL) ||
 	    !init_fifo(&ca->free[RESERVE_NONE], free, GFP_KERNEL) ||
 	    !init_fifo(&ca->free_inc,	free << 2, GFP_KERNEL) ||
@@ -1844,7 +1845,7 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
 				struct block_device *bdev, struct cache *ca)
 {
 	char name[BDEVNAME_SIZE];
-	const char *err = NULL;
+	const char *err = NULL; /* must be set for any error case */
 	int ret = 0;
 
 	memcpy(&ca->sb, sb, sizeof(struct cache_sb));
@@ -1861,8 +1862,13 @@ static int register_cache(struct cache_sb *sb, struct page *sb_page,
 		ca->discard = CACHE_DISCARD(&ca->sb);
 
 	ret = cache_alloc(ca);
-	if (ret != 0)
+	if (ret != 0) {
+		if (ret == -ENOMEM)
+			err = "cache_alloc(): -ENOMEM";
+		else
+			err = "cache_alloc(): unknown error";
 		goto err;
+	}
 
 	if (kobject_add(&ca->kobj, &part_to_dev(bdev->bd_part)->kobj, "bcache")) {
 		err = "error calling kobject_add";
diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index 97e446d54a15..6a2e8dd44a1b 100644
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -289,15 +289,13 @@ static int flakey_map(struct dm_target *ti, struct bio *bio)
 		pb->bio_submitted = true;
 
 		/*
-		 * Map reads as normal only if corrupt_bio_byte set.
+		 * Error reads if neither corrupt_bio_byte or drop_writes are set.
+		 * Otherwise, flakey_end_io() will decide if the reads should be modified.
 		 */
 		if (bio_data_dir(bio) == READ) {
-			/* If flags were specified, only corrupt those that match. */
-			if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) &&
-			    all_corrupt_bio_flags_match(bio, fc))
-				goto map_bio;
-			else
+			if (!fc->corrupt_bio_byte && !test_bit(DROP_WRITES, &fc->flags))
 				return -EIO;
+			goto map_bio;
 		}
 
 		/*
@@ -334,14 +332,21 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error)
 	struct flakey_c *fc = ti->private;
 	struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
 
-	/*
-	 * Corrupt successful READs while in down state.
-	 */
 	if (!error && pb->bio_submitted && (bio_data_dir(bio) == READ)) {
-		if (fc->corrupt_bio_byte)
+		if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) &&
+		    all_corrupt_bio_flags_match(bio, fc)) {
+			/*
+			 * Corrupt successful matching READs while in down state.
+			 */
 			corrupt_bio_data(bio, fc);
-		else
+
+		} else if (!test_bit(DROP_WRITES, &fc->flags)) {
+			/*
+			 * Error read during the down_interval if drop_writes
+			 * wasn't configured.
+			 */
 			return -EIO;
+		}
 	}
 
 	return error;
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 4ca2d1df5b44..07fc1ad42ec5 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -291,9 +291,10 @@ static void header_from_disk(struct log_header_core *core, struct log_header_dis
 	core->nr_regions = le64_to_cpu(disk->nr_regions);
 }
 
-static int rw_header(struct log_c *lc, int rw)
+static int rw_header(struct log_c *lc, int op)
 {
-	lc->io_req.bi_op = rw;
+	lc->io_req.bi_op = op;
+	lc->io_req.bi_op_flags = 0;
 
 	return dm_io(&lc->io_req, 1, &lc->header_location, NULL);
 }
@@ -316,7 +317,7 @@ static int read_header(struct log_c *log)
 {
 	int r;
 
-	r = rw_header(log, READ);
+	r = rw_header(log, REQ_OP_READ);
 	if (r)
 		return r;
 
@@ -630,7 +631,7 @@ static int disk_resume(struct dm_dirty_log *log)
 	header_to_disk(&lc->header, lc->disk_header);
 
 	/* write the new header */
-	r = rw_header(lc, WRITE);
+	r = rw_header(lc, REQ_OP_WRITE);
 	if (!r) {
 		r = flush_header(lc);
 		if (r)
@@ -698,7 +699,7 @@ static int disk_flush(struct dm_dirty_log *log)
 			log_clear_bit(lc, lc->clean_bits, i);
 	}
 
-	r = rw_header(lc, WRITE);
+	r = rw_header(lc, REQ_OP_WRITE);
 	if (r)
 		fail_log_device(lc);
 	else {