This is a note to let you know that I've just added the patch titled dm zoned: support zone sizes smaller than 128MiB to the 5.5-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: dm-zoned-support-zone-sizes-smaller-than-128mib.patch and it can be found in the queue-5.5 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From b39962950339912978484cdac50069258545d753 Mon Sep 17 00:00:00 2001 From: Dmitry Fomichev <dmitry.fomichev@xxxxxxx> Date: Mon, 23 Dec 2019 17:05:46 -0800 Subject: dm zoned: support zone sizes smaller than 128MiB From: Dmitry Fomichev <dmitry.fomichev@xxxxxxx> commit b39962950339912978484cdac50069258545d753 upstream. dm-zoned is observed to log failed kernel assertions and not work correctly when operating against a device with a zone size smaller than 128MiB (e.g. 32768 bits per 4K block). The reason is that the bitmap size per zone is calculated as zero with such a small zone size. Fix this problem and also make the code related to zone bitmap management be able to handle per zone bitmaps smaller than a single block. A dm-zoned-tools patch is required to properly format dm-zoned devices with zone sizes smaller than 128MiB. Fixes: 3b1a94c88b79 ("dm zoned: drive-managed zoned block device target") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Dmitry Fomichev <dmitry.fomichev@xxxxxxx> Reviewed-by: Damien Le Moal <damien.lemoal@xxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/dm-zoned-metadata.c | 23 ++++++++++++++--------- 1 file changed, 14 insertions(+), 9 deletions(-) --- a/drivers/md/dm-zoned-metadata.c +++ b/drivers/md/dm-zoned-metadata.c @@ -134,6 +134,7 @@ struct dmz_metadata { sector_t zone_bitmap_size; unsigned int zone_nr_bitmap_blocks; + unsigned int zone_bits_per_mblk; unsigned int nr_bitmap_blocks; unsigned int nr_map_blocks; @@ -1161,7 +1162,10 @@ static int dmz_init_zones(struct dmz_met /* Init */ zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3; - zmd->zone_nr_bitmap_blocks = zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT; + zmd->zone_nr_bitmap_blocks = + max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT); + zmd->zone_bits_per_mblk = min_t(sector_t, dev->zone_nr_blocks, + DMZ_BLOCK_SIZE_BITS); /* Allocate zone array */ zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL); @@ -1956,7 +1960,7 @@ int dmz_copy_valid_blocks(struct dmz_met dmz_release_mblock(zmd, to_mblk); dmz_release_mblock(zmd, from_mblk); - chunk_block += DMZ_BLOCK_SIZE_BITS; + chunk_block += zmd->zone_bits_per_mblk; } to_zone->weight = from_zone->weight; @@ -2017,7 +2021,7 @@ int dmz_validate_blocks(struct dmz_metad /* Set bits */ bit = chunk_block & DMZ_BLOCK_MASK_BITS; - nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); + nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit); count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits); if (count) { @@ -2096,7 +2100,7 @@ int dmz_invalidate_blocks(struct dmz_met /* Clear bits */ bit = chunk_block & DMZ_BLOCK_MASK_BITS; - nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); + nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit); count = dmz_clear_bits((unsigned long *)mblk->data, bit, nr_bits); @@ -2156,6 +2160,7 @@ static int dmz_to_next_set_block(struct { struct dmz_mblock *mblk; unsigned int bit, set_bit, nr_bits; + unsigned int zone_bits = zmd->zone_bits_per_mblk; unsigned long *bitmap; int n = 0; @@ -2170,15 +2175,15 @@ static int dmz_to_next_set_block(struct /* Get offset */ bitmap = (unsigned long *) mblk->data; bit = chunk_block & DMZ_BLOCK_MASK_BITS; - nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); + nr_bits = min(nr_blocks, zone_bits - bit); if (set) - set_bit = find_next_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit); + set_bit = find_next_bit(bitmap, zone_bits, bit); else - set_bit = find_next_zero_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit); + set_bit = find_next_zero_bit(bitmap, zone_bits, bit); dmz_release_mblock(zmd, mblk); n += set_bit - bit; - if (set_bit < DMZ_BLOCK_SIZE_BITS) + if (set_bit < zone_bits) break; nr_blocks -= nr_bits; @@ -2281,7 +2286,7 @@ static void dmz_get_zone_weight(struct d /* Count bits in this block */ bitmap = mblk->data; bit = chunk_block & DMZ_BLOCK_MASK_BITS; - nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); + nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit); n += dmz_count_bits(bitmap, bit, nr_bits); dmz_release_mblock(zmd, mblk); Patches currently in stable-queue which might be from dmitry.fomichev@xxxxxxx are queue-5.5/dm-zoned-support-zone-sizes-smaller-than-128mib.patch