diff options
| -rw-r--r-- | drivers/md/raid0.c | 32 | ||||
| -rw-r--r-- | drivers/md/raid0.h | 14 |
2 files changed, 45 insertions, 1 deletions
diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c index bc422eae2c95..ec611abda835 100644 --- a/drivers/md/raid0.c +++ b/drivers/md/raid0.c @@ -19,6 +19,9 @@ #include "raid0.h" #include "raid5.h" +static int default_layout = 0; +module_param(default_layout, int, 0644); + #define UNSUPPORTED_MDDEV_FLAGS \ ((1L << MD_HAS_JOURNAL) | \ (1L << MD_JOURNAL_CLEAN) | \ @@ -139,6 +142,19 @@ static int create_strip_zones(struct mddev *mddev, struct r0conf **private_conf) } pr_debug("md/raid0:%s: FINAL %d zones\n", mdname(mddev), conf->nr_strip_zones); + + if (conf->nr_strip_zones == 1) { + conf->layout = RAID0_ORIG_LAYOUT; + } else if (default_layout == RAID0_ORIG_LAYOUT || + default_layout == RAID0_ALT_MULTIZONE_LAYOUT) { + conf->layout = default_layout; + } else { + pr_err("md/raid0:%s: cannot assemble multi-zone RAID0 with default_layout setting\n", + mdname(mddev)); + pr_err("md/raid0: please set raid.default_layout to 1 or 2\n"); + err = -ENOTSUPP; + goto abort; + } /* * now since we have the hard sector sizes, we can make sure * chunk size is a multiple of that sector size @@ -547,10 +563,12 @@ static void raid0_handle_discard(struct mddev *mddev, struct bio *bio) static bool raid0_make_request(struct mddev *mddev, struct bio *bio) { + struct r0conf *conf = mddev->private; struct strip_zone *zone; struct md_rdev *tmp_dev; sector_t bio_sector; sector_t sector; + sector_t orig_sector; unsigned chunk_sects; unsigned sectors; @@ -584,8 +602,20 @@ static bool raid0_make_request(struct mddev *mddev, struct bio *bio) bio = split; } + orig_sector = sector; zone = find_zone(mddev->private, §or); - tmp_dev = map_sector(mddev, zone, sector, §or); + switch (conf->layout) { + case RAID0_ORIG_LAYOUT: + tmp_dev = map_sector(mddev, zone, orig_sector, §or); + break; + case RAID0_ALT_MULTIZONE_LAYOUT: + tmp_dev = map_sector(mddev, zone, sector, §or); + break; + default: + WARN("md/raid0:%s: Invalid layout\n", mdname(mddev)); + bio_io_error(bio); + return true; + } if (unlikely(is_mddev_broken(tmp_dev, "raid0"))) { bio_io_error(bio); diff --git a/drivers/md/raid0.h b/drivers/md/raid0.h index 540e65d92642..3816e5477db1 100644 --- a/drivers/md/raid0.h +++ b/drivers/md/raid0.h @@ -8,11 +8,25 @@ struct strip_zone { int nb_dev; /* # of devices attached to the zone */ }; +/* Linux 3.14 (20d0189b101) made an unintended change to + * the RAID0 layout for multi-zone arrays (where devices aren't all + * the same size. + * RAID0_ORIG_LAYOUT restores the original layout + * RAID0_ALT_MULTIZONE_LAYOUT uses the altered layout + * The layouts are identical when there is only one zone (all + * devices the same size). + */ + +enum r0layout { + RAID0_ORIG_LAYOUT = 1, + RAID0_ALT_MULTIZONE_LAYOUT = 2, +}; struct r0conf { struct strip_zone *strip_zone; struct md_rdev **devlist; /* lists of rdevs, pointed to * by strip_zone->dev */ int nr_strip_zones; + enum r0layout layout; }; #endif |