From: Naohiro Aota naohiro.aota@wdc.com
commit 95ca6599a589ee84c69f02d0e1d928c8d1367fb1 upstream.
The zoned mode need to reset a zone before using it. We rely on btrfs's original discard functionality (discarding unused block group range) to do the resetting.
While the commit 63a7cb130718 ("btrfs: auto enable discard=async when possible") made the discard done in an async manner, a zoned reset do not need to be async, as it is fast enough.
Even worth, delaying zone rests prevents using those zones again. So, let's disable async discard on the zoned mode.
Fixes: 63a7cb130718 ("btrfs: auto enable discard=async when possible") CC: stable@vger.kernel.org # 6.3+ Reviewed-by: Damien Le Moal dlemoal@kernel.org Reviewed-by: Christoph Hellwig hch@lst.de Signed-off-by: Naohiro Aota naohiro.aota@wdc.com Reviewed-by: David Sterba dsterba@suse.com [ update message text ] Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/disk-io.c | 7 ++++++- fs/btrfs/zoned.c | 3 +++ 2 files changed, 9 insertions(+), 1 deletion(-)
--- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3692,11 +3692,16 @@ int __cold open_ctree(struct super_block * For devices supporting discard turn on discard=async automatically, * unless it's already set or disabled. This could be turned off by * nodiscard for the same mount. + * + * The zoned mode piggy backs on the discard functionality for + * resetting a zone. There is no reason to delay the zone reset as it is + * fast enough. So, do not enable async discard for zoned mode. */ if (!(btrfs_test_opt(fs_info, DISCARD_SYNC) || btrfs_test_opt(fs_info, DISCARD_ASYNC) || btrfs_test_opt(fs_info, NODISCARD)) && - fs_info->fs_devices->discardable) { + fs_info->fs_devices->discardable && + !btrfs_is_zoned(fs_info)) { btrfs_set_and_info(fs_info, DISCARD_ASYNC, "auto enabling async discard"); } --- a/fs/btrfs/zoned.c +++ b/fs/btrfs/zoned.c @@ -804,6 +804,9 @@ int btrfs_check_mountopts_zoned(struct b return -EINVAL; }
+ btrfs_clear_and_info(info, DISCARD_ASYNC, + "zoned: async discard ignored and disabled for zoned mode"); + return 0; }