Re: [PATCH v2 02/11] md: merge mddev faillast_dev into mddev_flags

在 2025/11/24 14:31, Yu Kuai 写道:
> There is not need to use a separate field in struct mddev, there are no
> functional changes.
> 
> Signed-off-by: Yu Kuai <[email protected]>
> ---
>   drivers/md/md.c     | 10 ++++++----
>   drivers/md/md.h     |  3 ++-
>   drivers/md/raid0.c  |  3 ++-
>   drivers/md/raid1.c  |  4 ++--
>   drivers/md/raid10.c |  4 ++--
>   drivers/md/raid5.c  |  5 ++++-
>   6 files changed, 18 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/md/md.c b/drivers/md/md.c
> index b49fdee11a03..5dcfd0371090 100644
> --- a/drivers/md/md.c
> +++ b/drivers/md/md.c
> @@ -5864,11 +5864,11 @@ __ATTR(consistency_policy, S_IRUGO | S_IWUSR, consistency_policy_show,
>   
>   static ssize_t fail_last_dev_show(struct mddev *mddev, char *page)
>   {
> -	return sprintf(page, "%d\n", mddev->fail_last_dev);
> +	return sprintf(page, "%d\n", test_bit(MD_FAILLAST_DEV, &mddev->flags));
>   }
>   
>   /*
> - * Setting fail_last_dev to true to allow last device to be forcibly removed
> + * Setting MD_FAILLAST_DEV to allow last device to be forcibly removed
>    * from RAID1/RAID10.
>    */
>   static ssize_t
> @@ -5881,8 +5881,10 @@ fail_last_dev_store(struct mddev *mddev, const char *buf, size_t len)
>   	if (ret)
>   		return ret;
>   
> -	if (value != mddev->fail_last_dev)
> -		mddev->fail_last_dev = value;
> +	if (value)
> +		set_bit(MD_FAILLAST_DEV, &mddev->flags);
> +	else
> +		clear_bit(MD_FAILLAST_DEV, &mddev->flags);
>   
>   	return len;
>   }
> diff --git a/drivers/md/md.h b/drivers/md/md.h
> index b4c9aa600edd..297a104fba88 100644
> --- a/drivers/md/md.h
> +++ b/drivers/md/md.h
> @@ -341,6 +341,7 @@ struct md_cluster_operations;
>    * @MD_BROKEN: This is used to stop writes and mark array as failed.
>    * @MD_DELETED: This device is being deleted
>    * @MD_HAS_SUPERBLOCK: There is persistence sb in member disks.
> + * @MD_FAILLAST_DEV: Allow last rdev to be removed.
>    *
>    * change UNSUPPORTED_MDDEV_FLAGS for each array type if new flag is added
>    */
> @@ -358,6 +359,7 @@ enum mddev_flags {
>   	MD_DO_DELETE,
>   	MD_DELETED,
>   	MD_HAS_SUPERBLOCK,
> +	MD_FAILLAST_DEV,
>   };
>   
>   enum mddev_sb_flags {
> @@ -625,7 +627,6 @@ struct mddev {
>   	/* The sequence number for sync thread */
>   	atomic_t sync_seq;
>   
> -	bool	fail_last_dev:1;
>   	bool	serialize_policy:1;
>   };
>   
> diff --git a/drivers/md/raid0.c b/drivers/md/raid0.c
> index 47aee1b1d4d1..012d8402af28 100644
> --- a/drivers/md/raid0.c
> +++ b/drivers/md/raid0.c
> @@ -27,7 +27,8 @@ module_param(default_layout, int, 0644);
>   	 (1L << MD_JOURNAL_CLEAN) |	\
>   	 (1L << MD_FAILFAST_SUPPORTED) |\
>   	 (1L << MD_HAS_PPL) |		\
> -	 (1L << MD_HAS_MULTIPLE_PPLS))
> +	 (1L << MD_HAS_MULTIPLE_PPLS) |	\
> +	 (1L << MD_FAILLAST_DEV))
>   
>   /*
>    * inform the user of the raid configuration
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 57d50465eed1..98b5c93810bb 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -1746,7 +1746,7 @@ static void raid1_status(struct seq_file *seq, struct mddev *mddev)
>    *	- &mddev->degraded is bumped.
>    *
>    * @rdev is marked as &Faulty excluding case when array is failed and
> - * &mddev->fail_last_dev is off.
> + * MD_FAILLAST_DEV is not set.
>    */
>   static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
>   {
> @@ -1759,7 +1759,7 @@ static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
>   	    (conf->raid_disks - mddev->degraded) == 1) {
>   		set_bit(MD_BROKEN, &mddev->flags);
>   
> -		if (!mddev->fail_last_dev) {
> +		if (!test_bit(MD_FAILLAST_DEV, &mddev->flags)) {
>   			conf->recovery_disabled = mddev->recovery_disabled;
>   			spin_unlock_irqrestore(&conf->device_lock, flags);
>   			return;
> diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
> index 84be4cc7e873..09328e032f14 100644
> --- a/drivers/md/raid10.c
> +++ b/drivers/md/raid10.c
> @@ -1990,7 +1990,7 @@ static int enough(struct r10conf *conf, int ignore)
>    *	- &mddev->degraded is bumped.
>    *
>    * @rdev is marked as &Faulty excluding case when array is failed and
> - * &mddev->fail_last_dev is off.
> + * MD_FAILLAST_DEV is not set.
>    */
>   static void raid10_error(struct mddev *mddev, struct md_rdev *rdev)
>   {
> @@ -2002,7 +2002,7 @@ static void raid10_error(struct mddev *mddev, struct md_rdev *rdev)
>   	if (test_bit(In_sync, &rdev->flags) && !enough(conf, rdev->raid_disk)) {
>   		set_bit(MD_BROKEN, &mddev->flags);
>   
> -		if (!mddev->fail_last_dev) {
> +		if (!test_bit(MD_FAILLAST_DEV, &mddev->flags)) {
>   			spin_unlock_irqrestore(&conf->device_lock, flags);
>   			return;
>   		}
> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
> index cdbc7eba5c54..74f6729864fa 100644
> --- a/drivers/md/raid5.c
> +++ b/drivers/md/raid5.c
> @@ -56,7 +56,10 @@
>   #include "md-bitmap.h"
>   #include "raid5-log.h"
>   
> -#define UNSUPPORTED_MDDEV_FLAGS	(1L << MD_FAILFAST_SUPPORTED)
> +#define UNSUPPORTED_MDDEV_FLAGS		\
> +	((1L << MD_FAILFAST_SUPPORTED) |	\
> +	 (1L << MD_FAILLAST_DEV))
> +
>   
>   #define cpu_to_group(cpu) cpu_to_node(cpu)
>   #define ANY_GROUP NUMA_NO_NODE
LGTM

Reviewed-by: Li Nan <[email protected]>

-- 
Thanks,
Nan