The patch below does not apply to the 6.12-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-6.12.y git checkout FETCH_HEAD git cherry-pick -x 694ce5e143d67267ad26b04463e790a597500b00 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2025081844-another-thirteen-4153@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 694ce5e143d67267ad26b04463e790a597500b00 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn johannes.thumshirn@wdc.com Date: Tue, 3 Jun 2025 08:14:01 +0200 Subject: [PATCH] btrfs: zoned: reserve data_reloc block group on mount
Create a block group dedicated for data relocation on mount of a zoned filesystem.
If there is already more than one empty DATA block group on mount, this one is picked for the data relocation block group, instead of a newly created one.
This is done to ensure, there is always space for performing garbage collection and the filesystem is not hitting ENOSPC under heavy overwrite workloads.
CC: stable@vger.kernel.org # 6.6+ Reviewed-by: Filipe Manana fdmanana@suse.com Signed-off-by: Johannes Thumshirn johannes.thumshirn@wdc.com Signed-off-by: David Sterba dsterba@suse.com
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 0d6ad7512f21..4cfcd879dc5e 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3561,6 +3561,7 @@ int __cold open_ctree(struct super_block *sb, struct btrfs_fs_devices *fs_device goto fail_sysfs; }
+ btrfs_zoned_reserve_data_reloc_bg(fs_info); btrfs_free_zone_cache(fs_info);
btrfs_check_active_zone_reservation(fs_info); diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c index 805f2eca20e9..4ab7808bca62 100644 --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -17,6 +17,7 @@ #include "fs.h" #include "accessors.h" #include "bio.h" +#include "transaction.h"
/* Maximum number of zones to report per blkdev_report_zones() call */ #define BTRFS_REPORT_NR_ZONES 4096 @@ -2501,6 +2502,66 @@ void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg) spin_unlock(&fs_info->relocation_bg_lock); }
+void btrfs_zoned_reserve_data_reloc_bg(struct btrfs_fs_info *fs_info) +{ + struct btrfs_space_info *data_sinfo = fs_info->data_sinfo; + struct btrfs_space_info *space_info = data_sinfo->sub_group[0]; + struct btrfs_trans_handle *trans; + struct btrfs_block_group *bg; + struct list_head *bg_list; + u64 alloc_flags; + bool initial = false; + bool did_chunk_alloc = false; + int index; + int ret; + + if (!btrfs_is_zoned(fs_info)) + return; + + if (fs_info->data_reloc_bg) + return; + + if (sb_rdonly(fs_info->sb)) + return; + + ASSERT(space_info->subgroup_id == BTRFS_SUB_GROUP_DATA_RELOC); + alloc_flags = btrfs_get_alloc_profile(fs_info, space_info->flags); + index = btrfs_bg_flags_to_raid_index(alloc_flags); + + bg_list = &data_sinfo->block_groups[index]; +again: + list_for_each_entry(bg, bg_list, list) { + if (bg->used > 0) + continue; + + if (!initial) { + initial = true; + continue; + } + + fs_info->data_reloc_bg = bg->start; + set_bit(BLOCK_GROUP_FLAG_ZONED_DATA_RELOC, &bg->runtime_flags); + btrfs_zone_activate(bg); + + return; + } + + if (did_chunk_alloc) + return; + + trans = btrfs_join_transaction(fs_info->tree_root); + if (IS_ERR(trans)) + return; + + ret = btrfs_chunk_alloc(trans, space_info, alloc_flags, CHUNK_ALLOC_FORCE); + btrfs_end_transaction(trans); + if (ret == 1) { + did_chunk_alloc = true; + bg_list = &space_info->block_groups[index]; + goto again; + } +} + void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info) { struct btrfs_fs_devices *fs_devices = fs_info->fs_devices; diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h index 9672bf4c3335..6e11533b8e14 100644 --- a/fs/btrfs/zoned.h +++ b/fs/btrfs/zoned.h @@ -88,6 +88,7 @@ void btrfs_zone_finish_endio(struct btrfs_fs_info *fs_info, u64 logical, void btrfs_schedule_zone_finish_bg(struct btrfs_block_group *bg, struct extent_buffer *eb); void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg); +void btrfs_zoned_reserve_data_reloc_bg(struct btrfs_fs_info *fs_info); void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info); bool btrfs_zoned_should_reclaim(const struct btrfs_fs_info *fs_info); void btrfs_zoned_release_data_reloc_bg(struct btrfs_fs_info *fs_info, u64 logical, @@ -241,6 +242,8 @@ static inline void btrfs_schedule_zone_finish_bg(struct btrfs_block_group *bg,
static inline void btrfs_clear_data_reloc_bg(struct btrfs_block_group *bg) { }
+static inline void btrfs_zoned_reserve_data_reloc_bg(struct btrfs_fs_info *fs_info) { } + static inline void btrfs_free_zone_cache(struct btrfs_fs_info *fs_info) { }
static inline bool btrfs_zoned_should_reclaim(const struct btrfs_fs_info *fs_info)