Re: [RFC PATCH 5/5] md/raid1: introduce rectify action to repair badblocks

在 2025/12/31 15:09, Zheng Qixing 写道:
> From: Zheng Qixing <[email protected]>
> 
> Add support for repairing known badblocks in RAID1. When disks
> have known badblocks (shown in sysfs bad_blocks), data can be
> read from other healthy disks in the array and written to repair
> the badblock areas and clear it in bad_blocks.
> 
> echo rectify > sync_action can trigger this action.
> 
> Signed-off-by: Zheng Qixing <[email protected]>

> +static void end_rectify_read(struct bio *bio)
> +{
> +	struct r1bio *r1_bio = get_resync_r1bio(bio);
> +	struct r1conf *conf = r1_bio->mddev->private;
> +	struct md_rdev *rdev;
> +	struct bio *next_bio;
> +	bool all_fail = true;
> +	int i;
> +
> +	update_head_pos(r1_bio->read_disk, r1_bio);
> +
> +	if (!bio->bi_status) {
> +		set_bit(R1BIO_Uptodate, &r1_bio->state);
> +		goto out;
> +	}
> +
> +	for (i = r1_bio->read_disk + 1; i < conf->raid_disks; i++) {
> +		rdev = conf->mirrors[i].rdev;
> +		if (!rdev || test_bit(Faulty, &rdev->flags))
> +			continue;
> +
> +		next_bio = r1_bio->bios[i];
> +		if (next_bio->bi_end_io == end_rectify_read) {
> +			next_bio->bi_opf &= ~MD_FAILFAST;

Why set MD_FAILFAST and clear it soon?
And submit_rectify_read() will clear it again.

> +static void rectify_request_write(struct mddev *mddev, struct r1bio *r1_bio)
> +{
> +	struct r1conf *conf = mddev->private;
> +	struct bio *wbio = NULL;
> +	int wcnt = 0;
> +	int i;
> +
> +	if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) {
> +		submit_rectify_read(r1_bio);
> +		return;
> +	}
> +
> +	atomic_set(&r1_bio->remaining, 0);
> +	for (i = 0; i < conf->raid_disks; i++) {
> +		wbio = r1_bio->bios[i];
> +		if (wbio->bi_end_io == end_rectify_write) {
> +			atomic_inc(&r1_bio->remaining);
> +			wcnt++;
> +			submit_bio_noacct(wbio);
> +		}
> +	}
> +
> +	if (unlikely(!wcnt)) {
> +		md_done_sync(r1_bio->mddev, r1_bio->sectors);
> +		put_buf(r1_bio);
> +	}

How can 'wcnt' be 0?

> +}
> +
> +static void handle_rectify_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
> +{
> +	struct md_rdev *rdev;
> +	struct bio *bio;
> +	int i;
> +
> +	for (i = 0; i < conf->raid_disks; i++) {
> +		rdev = conf->mirrors[i].rdev;
> +		bio = r1_bio->bios[i];
> +		if (bio->bi_end_io == NULL)
> +			continue;
> +
> +		if (!bio->bi_status && bio->bi_end_io == end_rectify_write &&
> +		    test_bit(R1BIO_MadeGood, &r1_bio->state)) {
> +			rdev_clear_badblocks(rdev, r1_bio->sector,
> +					     r1_bio->sectors, 0);
> +		}

Reuse handle_sync_write_finished() seems better.

> +	}
> +
> +	md_done_sync(r1_bio->mddev, r1_bio->sectors);
> +	put_buf(r1_bio);
> +}
> +

-- 
Thanks,
Nan