From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 4056581751; Wed, 7 Aug 2024 15:10:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723043453; cv=none; b=KJk9jgQGaQSHymyBXJssf8o52M2i4eZ52VarFtzIQ3p5v/8td7Gz768OLICRzUPI82IaaCTABKznIi7OgBbShAkhkNA3HSFCr9Tes5S4bgF09mMnVvDYifRnd59/GM4DhrY9PcdrPF2B6x7kmwmhHzXJpjnE4xOyqtsIS0l4rvM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723043453; c=relaxed/simple; bh=om8Pkij2CjO7QJlYBM1IsC5uMSACSdLDkiG/p1QeBV8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gynUWDQ7XAuezgdEIRrPUL3MZmyeku5p1tP9BNCRrh86TL6EkUwl0NNxIl9RwU6T2Nt+PUXA+tn3YKQ5yE65PHsZepLBf3dCCXpLLAYLIR8N6AbJNLgiw7+KajPjFE6Md+/+X9F0cmnWJcncSqz3X2y/6CrtQGY3YSns9qlmO7o= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Y3m9jfEy; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Y3m9jfEy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6FD5C32781; Wed, 7 Aug 2024 15:10:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1723043453; bh=om8Pkij2CjO7QJlYBM1IsC5uMSACSdLDkiG/p1QeBV8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y3m9jfEyYw9oVj32aIp+wBwKXntJv5Vw9Gdm44Q9pv6+wpWxcjrkU3Yx8FsC3HcZL BTdF8vcqGrrR7HcHksaVjILTCG3HURqn3653WTSp1juQunZs6ZRXMcBKwuFbZVCG7K jDudunbPiRdwOtVf65hoRjXuVMrEnEQw4N1IiW1k= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Naohiro Aota , Josef Bacik , Johannes Thumshirn , David Sterba Subject: [PATCH 6.6 097/121] btrfs: zoned: fix zone_unusable accounting on making block group read-write again Date: Wed, 7 Aug 2024 17:00:29 +0200 Message-ID: <20240807150022.576335004@linuxfoundation.org> X-Mailer: git-send-email 2.46.0 In-Reply-To: <20240807150019.412911622@linuxfoundation.org> References: <20240807150019.412911622@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Naohiro Aota commit 8cd44dd1d17a23d5cc8c443c659ca57aa76e2fa5 upstream. 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 Reviewed-by: Josef Bacik Reviewed-by: Johannes Thumshirn Signed-off-by: David Sterba Signed-off-by: Greg Kroah-Hartman --- fs/btrfs/block-group.c | 13 ++++++++----- fs/btrfs/extent-tree.c | 3 ++- fs/btrfs/free-space-cache.c | 4 +++- fs/btrfs/space-info.c | 2 +- fs/btrfs/space-info.h | 1 + include/trace/events/btrfs.h | 8 ++++++++ 6 files changed, 23 insertions(+), 8 deletions(-) --- a/fs/btrfs/block-group.c +++ b/fs/btrfs/block-group.c @@ -1214,8 +1214,8 @@ int btrfs_remove_block_group(struct btrf 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); @@ -1399,7 +1399,8 @@ static int inc_block_group_ro(struct btr 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++; @@ -3023,9 +3024,11 @@ void btrfs_dec_block_group_ro(struct btr 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 - --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2749,7 +2749,8 @@ static int unpin_extent_range(struct btr 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); --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -2721,8 +2721,10 @@ static int __btrfs_add_free_space_zoned( * 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); --- a/fs/btrfs/space-info.c +++ b/fs/btrfs/space-info.c @@ -312,7 +312,7 @@ void btrfs_add_bg_to_space_info(struct b 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); --- a/fs/btrfs/space-info.h +++ b/fs/btrfs/space-info.h @@ -197,6 +197,7 @@ btrfs_space_info_update_##name(struct bt 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, --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -2430,6 +2430,14 @@ DEFINE_EVENT(btrfs__space_info_update, u 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,