Commit 486f6055 authored by Logan Gunthorpe's avatar Logan Gunthorpe Committed by Jens Axboe
Browse files

md/raid5: Check all disks in a stripe_head for reshape progress 



When testing if a previous stripe has had reshape expand past it, use
the earliest or latest logical sector in all the disks for that stripe
head. This will allow adding multiple disks at a time in a subesquent
patch.

To do this cleaner, refactor the check into a helper function called
stripe_ahead_of_reshape().

Signed-off-by: default avatarLogan Gunthorpe <logang@deltatee.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarSong Liu <song@kernel.org>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4ad1d984

drivers/md/raid5.c

+39 −14
Original line number Diff line number Diff line
@@ -5819,6 +5819,40 @@ static bool ahead_of_reshape(struct mddev *mddev, sector_t sector, 
					  sector >= reshape_sector;

}



static bool range_ahead_of_reshape(struct mddev *mddev, sector_t min,

				   sector_t max, sector_t reshape_sector)

{

	return mddev->reshape_backwards ? max < reshape_sector :

					  min >= reshape_sector;

}



static bool stripe_ahead_of_reshape(struct mddev *mddev, struct r5conf *conf,

				    struct stripe_head *sh)

{

	sector_t max_sector = 0, min_sector = MaxSector;

	bool ret = false;

	int dd_idx;



	for (dd_idx = 0; dd_idx < sh->disks; dd_idx++) {

		if (dd_idx == sh->pd_idx)

			continue;



		min_sector = min(min_sector, sh->dev[dd_idx].sector);

		max_sector = min(max_sector, sh->dev[dd_idx].sector);

	}



	spin_lock_irq(&conf->device_lock);



	if (!range_ahead_of_reshape(mddev, min_sector, max_sector,

				     conf->reshape_progress))

		/* mismatch, need to try again */

		ret = true;



	spin_unlock_irq(&conf->device_lock);



	return ret;

}



enum stripe_result {

	STRIPE_SUCCESS = 0,

	STRIPE_RETRY,
@@ -5883,28 +5917,19 @@ static enum stripe_result make_stripe_request(struct mddev *mddev, 
		return STRIPE_FAIL;

	}



	if (unlikely(previous)) {

	if (unlikely(previous) &&

	    stripe_ahead_of_reshape(mddev, conf, sh)) {

		/*

		 * Expansion might have moved on while waiting for a

		 * stripe, so we must do the range check again.

		 * Expansion moved on while waiting for a stripe.

		 * Expansion could still move past after this

		 * test, but as we are holding a reference to

		 * 'sh', we know that if that happens,

		 *  STRIPE_EXPANDING will get set and the expansion

		 * won't proceed until we finish with the stripe.

		 */

		int must_retry = 0;

		spin_lock_irq(&conf->device_lock);

		if (!ahead_of_reshape(mddev, logical_sector,

				      conf->reshape_progress))

			/* mismatch, need to try again */

			must_retry = 1;

		spin_unlock_irq(&conf->device_lock);

		if (must_retry) {

		ret = STRIPE_SCHEDULE_AND_RETRY;

		goto out_release;

	}

	}



	if (read_seqcount_retry(&conf->gen_lock, seq)) {

		/* Might have got the wrong stripe_head by accident */