The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 8cd44dd1d17a23d5cc8c443c659ca57aa76e2fa5 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2024080751-importer-postbox-eb90@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^..

Possible dependencies:

8cd44dd1d17a ("btrfs: zoned: fix zone_unusable accounting on making block group read-write again") 9d4b0a129a0d ("btrfs: simplify arguments of btrfs_update_space_info and rename") 6a921de58992 ("btrfs: zoned: introduce space_info->active_total_bytes") f6fca3917b4d ("btrfs: store chunk size in space-info struct") b8bea09a456f ("btrfs: add trace event for submitted RAID56 bio") c67c68eb57f1 ("btrfs: use integrated bitmaps for btrfs_raid_bio::dbitmap and finish_pbitmap") 143823cf4d5a ("btrfs: fix typos in comments") 385de0ef387d ("btrfs: use a normal workqueue for rmw_workers") a7b8e39c922b ("btrfs: raid56: enable subpage support for RAID56") 3907ce293d68 ("btrfs: raid56: make alloc_rbio_essential_pages() subpage compatible") ac26df8b3b02 ("btrfs: raid56: remove btrfs_raid_bio::bio_pages array") 07e4d3808047 ("btrfs: raid56: make __raid_recover_endio_io() subpage compatible") 46900662d02f ("btrfs: raid56: make finish_parity_scrub() subpage compatible") 3e77605d6a81 ("btrfs: raid56: make rbio_add_io_page() subpage compatible") 00425dd976d3 ("btrfs: raid56: introduce btrfs_raid_bio::bio_sectors") eb3570607c8c ("btrfs: raid56: introduce btrfs_raid_bio::stripe_sectors") 94efbe19b9f1 ("btrfs: raid56: introduce new cached members for btrfs_raid_bio") 29b068382c6f ("btrfs: raid56: make btrfs_raid_bio more compact") 843de58b3e31 ("btrfs: raid56: open code rbio_nr_pages()") cc353a8be2fd ("btrfs: reduce width for stripe_len from u64 to u32")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 8cd44dd1d17a23d5cc8c443c659ca57aa76e2fa5 Mon Sep 17 00:00:00 2001 From: Naohiro Aota naohiro.aota@wdc.com Date: Wed, 15 Feb 2023 09:18:02 +0900 Subject: [PATCH] btrfs: zoned: fix zone_unusable accounting on making block group read-write again

When btrfs makes a block group read-only, it adds all free regions in the block group to space_info->bytes_readonly. That free space excludes reserved and pinned regions. OTOH, when btrfs makes the block group read-write again, it moves all the unused regions into the block group's zone_unusable. That unused region includes reserved and pinned regions. As a result, it counts too much zone_unusable bytes.

Fortunately (or unfortunately), having erroneous zone_unusable does not affect the calculation of space_info->bytes_readonly, because free space (num_bytes in btrfs_dec_block_group_ro) calculation is done based on the erroneous zone_unusable and it reduces the num_bytes just to cancel the error.

This behavior can be easily discovered by adding a WARN_ON to check e.g, "bg->pinned > 0" in btrfs_dec_block_group_ro(), and running fstests test case like btrfs/282.

Fix it by properly considering pinned and reserved in btrfs_dec_block_group_ro(). Also, add a WARN_ON and introduce btrfs_space_info_update_bytes_zone_unusable() to catch a similar mistake.

Fixes: 169e0da91a21 ("btrfs: zoned: track unusable bytes for zones") CC: stable@vger.kernel.org # 5.15+ Signed-off-by: Naohiro Aota naohiro.aota@wdc.com Reviewed-by: Josef Bacik josef@toxicpanda.com Reviewed-by: Johannes Thumshirn johannes.thumshirn@wdc.com Signed-off-by: David Sterba dsterba@suse.com

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c index 498442d0c216..2e49d978f504 100644 --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1223,8 +1223,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, block_group->space_info->total_bytes -= block_group->length; block_group->space_info->bytes_readonly -= (block_group->length - block_group->zone_unusable); - block_group->space_info->bytes_zone_unusable -= - block_group->zone_unusable; + btrfs_space_info_update_bytes_zone_unusable(fs_info, block_group->space_info, + -block_group->zone_unusable); block_group->space_info->disk_total -= block_group->length * factor;

spin_unlock(&block_group->space_info->lock); @@ -1396,7 +1396,8 @@ static int inc_block_group_ro(struct btrfs_block_group *cache, int force) if (btrfs_is_zoned(cache->fs_info)) { /* Migrate zone_unusable bytes to readonly */ sinfo->bytes_readonly += cache->zone_unusable; - sinfo->bytes_zone_unusable -= cache->zone_unusable; + btrfs_space_info_update_bytes_zone_unusable(cache->fs_info, sinfo, + -cache->zone_unusable); cache->zone_unusable = 0; } cache->ro++; @@ -3056,9 +3057,11 @@ void btrfs_dec_block_group_ro(struct btrfs_block_group *cache) if (btrfs_is_zoned(cache->fs_info)) { /* Migrate zone_unusable bytes back */ cache->zone_unusable = - (cache->alloc_offset - cache->used) + + (cache->alloc_offset - cache->used - cache->pinned - + cache->reserved) + (cache->length - cache->zone_capacity); - sinfo->bytes_zone_unusable += cache->zone_unusable; + btrfs_space_info_update_bytes_zone_unusable(cache->fs_info, sinfo, + cache->zone_unusable); sinfo->bytes_readonly -= cache->zone_unusable; } num_bytes = cache->length - cache->reserved - diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index d77498e7671c..ff9f0d41987e 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2793,7 +2793,8 @@ static int unpin_extent_range(struct btrfs_fs_info *fs_info, readonly = true; } else if (btrfs_is_zoned(fs_info)) { /* Need reset before reusing in a zoned block group */ - space_info->bytes_zone_unusable += len; + btrfs_space_info_update_bytes_zone_unusable(fs_info, space_info, + len); readonly = true; } spin_unlock(&cache->lock); diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index 3f9b7507543a..f5996a43db24 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -2723,8 +2723,10 @@ static int __btrfs_add_free_space_zoned(struct btrfs_block_group *block_group, * If the block group is read-only, we should account freed space into * bytes_readonly. */ - if (!block_group->ro) + if (!block_group->ro) { block_group->zone_unusable += to_unusable; + WARN_ON(block_group->zone_unusable > block_group->length); + } spin_unlock(&ctl->tree_lock); if (!used) { spin_lock(&block_group->lock); diff --git a/fs/btrfs/space-info.c b/fs/btrfs/space-info.c index c1d9d3664400..68e14fd48638 100644 --- a/fs/btrfs/space-info.c +++ b/fs/btrfs/space-info.c @@ -316,7 +316,7 @@ void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info, found->bytes_used += block_group->used; found->disk_used += block_group->used * factor; found->bytes_readonly += block_group->bytes_super; - found->bytes_zone_unusable += block_group->zone_unusable; + btrfs_space_info_update_bytes_zone_unusable(info, found, block_group->zone_unusable); if (block_group->length > 0) found->full = 0; btrfs_try_granting_tickets(info, found); diff --git a/fs/btrfs/space-info.h b/fs/btrfs/space-info.h index 4db8a0267c16..88b44221ce97 100644 --- a/fs/btrfs/space-info.h +++ b/fs/btrfs/space-info.h @@ -249,6 +249,7 @@ btrfs_space_info_update_##name(struct btrfs_fs_info *fs_info, \

DECLARE_SPACE_INFO_UPDATE(bytes_may_use, "space_info"); DECLARE_SPACE_INFO_UPDATE(bytes_pinned, "pinned"); +DECLARE_SPACE_INFO_UPDATE(bytes_zone_unusable, "zone_unusable");

int btrfs_init_space_info(struct btrfs_fs_info *fs_info); void btrfs_add_bg_to_space_info(struct btrfs_fs_info *info, diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index eeb56975bee7..de55a555d95b 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -2383,6 +2383,14 @@ DEFINE_EVENT(btrfs__space_info_update, update_bytes_pinned, TP_ARGS(fs_info, sinfo, old, diff) );

+DEFINE_EVENT(btrfs__space_info_update, update_bytes_zone_unusable, + + TP_PROTO(const struct btrfs_fs_info *fs_info, + const struct btrfs_space_info *sinfo, u64 old, s64 diff), + + TP_ARGS(fs_info, sinfo, old, diff) +); + DECLARE_EVENT_CLASS(btrfs_raid56_bio,

TP_PROTO(const struct btrfs_raid_bio *rbio,