Re: [PATCH v2 03/14] md/raid1: use folio for tmppage

["Yu Kuai" <yukuai@fnnas.com>]

Hi,

在 2026/1/28 15:56, linan666@huaweicloud.com 写道:
> From: Li Nan <linan122@huawei.com>
>
> Convert tmppage to tmpfolio and use it throughout in raid1.
>
> Signed-off-by: Li Nan <linan122@huawei.com>
> Reviewed-by: Xiao Ni <xni@redhat.com>
> ---
>   drivers/md/raid1.h |  2 +-
>   drivers/md/raid1.c | 18 ++++++++++--------
>   2 files changed, 11 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/md/raid1.h b/drivers/md/raid1.h
> index c98d43a7ae99..d480b3a8c2c4 100644
> --- a/drivers/md/raid1.h
> +++ b/drivers/md/raid1.h
> @@ -101,7 +101,7 @@ struct r1conf {
>   	/* temporary buffer to synchronous IO when attempting to repair
>   	 * a read error.
>   	 */
> -	struct page		*tmppage;
> +	struct folio		*tmpfolio;
>   
>   	/* When taking over an array from a different personality, we store
>   	 * the new thread here until we fully activate the array.
> diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
> index 407925951299..43453f1a04f4 100644
> --- a/drivers/md/raid1.c
> +++ b/drivers/md/raid1.c
> @@ -2417,8 +2417,8 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
>   			      rdev->recovery_offset >= sect + s)) &&
>   			    rdev_has_badblock(rdev, sect, s) == 0) {
>   				atomic_inc(&rdev->nr_pending);
> -				if (sync_page_io(rdev, sect, s<<9,
> -					 conf->tmppage, REQ_OP_READ, false))
> +				if (sync_folio_io(rdev, sect, s<<9, 0,
> +					 conf->tmpfolio, REQ_OP_READ, false))
>   					success = 1;
>   				rdev_dec_pending(rdev, mddev);
>   				if (success)
> @@ -2447,7 +2447,8 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
>   			    !test_bit(Faulty, &rdev->flags)) {
>   				atomic_inc(&rdev->nr_pending);
>   				r1_sync_page_io(rdev, sect, s,
> -						conf->tmppage, REQ_OP_WRITE);
> +						folio_page(conf->tmpfolio, 0),
> +						REQ_OP_WRITE);
>   				rdev_dec_pending(rdev, mddev);
>   			}
>   		}
> @@ -2461,7 +2462,8 @@ static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
>   			    !test_bit(Faulty, &rdev->flags)) {
>   				atomic_inc(&rdev->nr_pending);
>   				if (r1_sync_page_io(rdev, sect, s,
> -						conf->tmppage, REQ_OP_READ)) {
> +						folio_page(conf->tmpfolio, 0),
> +						REQ_OP_READ)) {
>   					atomic_add(s, &rdev->corrected_errors);
>   					pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %pg)\n",
>   						mdname(mddev), s,
> @@ -3120,8 +3122,8 @@ static struct r1conf *setup_conf(struct mddev *mddev)
>   	if (!conf->mirrors)
>   		goto abort;
>   
> -	conf->tmppage = alloc_page(GFP_KERNEL);
> -	if (!conf->tmppage)
> +	conf->tmpfolio = folio_alloc(GFP_KERNEL, 0);
> +	if (!conf->tmpfolio)
>   		goto abort;
>   
>   	r1bio_size = offsetof(struct r1bio, bios[mddev->raid_disks * 2]);
> @@ -3196,7 +3198,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
>   	if (conf) {
>   		mempool_destroy(conf->r1bio_pool);
>   		kfree(conf->mirrors);
> -		safe_put_page(conf->tmppage);
> +		folio_put(conf->tmpfolio);

Is this safe? folio_put() can't be called with NULL.

>   		kfree(conf->nr_pending);
>   		kfree(conf->nr_waiting);
>   		kfree(conf->nr_queued);
> @@ -3310,7 +3312,7 @@ static void raid1_free(struct mddev *mddev, void *priv)
>   
>   	mempool_destroy(conf->r1bio_pool);
>   	kfree(conf->mirrors);
> -	safe_put_page(conf->tmppage);
> +	folio_put(conf->tmpfolio);

Same here.

>   	kfree(conf->nr_pending);
>   	kfree(conf->nr_waiting);
>   	kfree(conf->nr_queued);

-- 
Thansk,
Kuai