47 lines
2.1 KiB
Diff
47 lines
2.1 KiB
Diff
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From 4086c1a804741c9c8f418d6088e8c531f2a481f3 Mon Sep 17 00:00:00 2001
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From: Naohiro Aota <naohiro.aota@wdc.com>
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Date: Tue, 1 Oct 2024 17:03:32 +0900
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Subject: btrfs: zoned: fix zone unusable accounting for freed reserved extent
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When btrfs reserves an extent and does not use it (e.g, by an error), it
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calls btrfs_free_reserved_extent() to free the reserved extent. In the
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process, it calls btrfs_add_free_space() and then it accounts the region
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bytes as block_group->zone_unusable.
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However, it leaves the space_info->bytes_zone_unusable side not updated. As
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a result, ENOSPC can happen while a space_info reservation succeeded. The
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reservation is fine because the freed region is not added in
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space_info->bytes_zone_unusable, leaving that space as "free". OTOH,
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corresponding block group counts it as zone_unusable and its allocation
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pointer is not rewound, we cannot allocate an extent from that block group.
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That will also negate space_info's async/sync reclaim process, and cause an
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ENOSPC error from the extent allocation process.
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Fix that by returning the space to space_info->bytes_zone_unusable.
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Ideally, since a bio is not submitted for this reserved region, we should
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return the space to free space and rewind the allocation pointer. But, it
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needs rework on extent allocation handling, so let it work in this way for
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now.
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Fixes: 169e0da91a21 ("btrfs: zoned: track unusable bytes for zones")
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CC: stable@vger.kernel.org # 5.15+
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Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
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Signed-off-by: Naohiro Aota <naohiro.aota@wdc.com>
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Reviewed-by: David Sterba <dsterba@suse.com>
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Signed-off-by: David Sterba <dsterba@suse.com>
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---
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fs/btrfs/block-group.c | 2 ++
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1 file changed, 2 insertions(+)
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--- a/fs/btrfs/block-group.c
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+++ b/fs/btrfs/block-group.c
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@@ -3819,6 +3819,8 @@ void btrfs_free_reserved_bytes(struct bt
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spin_lock(&cache->lock);
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if (cache->ro)
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space_info->bytes_readonly += num_bytes;
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+ else if (btrfs_is_zoned(cache->fs_info))
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+ space_info->bytes_zone_unusable += num_bytes;
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cache->reserved -= num_bytes;
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space_info->bytes_reserved -= num_bytes;
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space_info->max_extent_size = 0;
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