Commit bc0934f0 authored by Shaohua Li's avatar Shaohua Li Committed by NeilBrown
Browse files

raid5: support sync request 



REQ_SYNC is ignored in current raid5 code. Block layer does use it to do
policy,
for example ioscheduler. This patch adds it.

Signed-off-by: default avatarShaohua Li <shli@fusionio.com>
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
parent cceeca43

drivers/md/raid5.c

+10 −2
Original line number Diff line number Diff line
@@ -539,6 +539,8 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) 
			replace_only = 1;

		} else

			continue;

		if (test_and_clear_bit(R5_SyncIO, &sh->dev[i].flags))

			rw |= REQ_SYNC;



		bi = &sh->dev[i].req;

		rbi = &sh->dev[i].rreq; /* For writing to replacement */
@@ -1145,6 +1147,8 @@ ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) 
				dev->sector + STRIPE_SECTORS) {

				if (wbi->bi_rw & REQ_FUA)

					set_bit(R5_WantFUA, &dev->flags);

				if (wbi->bi_rw & REQ_SYNC)

					set_bit(R5_SyncIO, &dev->flags);

				tx = async_copy_data(1, wbi, dev->page,

					dev->sector, tx);

				wbi = r5_next_bio(wbi, dev->sector);
@@ -1162,13 +1166,15 @@ static void ops_complete_reconstruct(void *stripe_head_ref) 
	int pd_idx = sh->pd_idx;

	int qd_idx = sh->qd_idx;

	int i;

	bool fua = false;

	bool fua = false, sync = false;



	pr_debug("%s: stripe %llu\n", __func__,

		(unsigned long long)sh->sector);



	for (i = disks; i--; )

	for (i = disks; i--; ) {

		fua |= test_bit(R5_WantFUA, &sh->dev[i].flags);

		sync |= test_bit(R5_SyncIO, &sh->dev[i].flags);

	}



	for (i = disks; i--; ) {

		struct r5dev *dev = &sh->dev[i];
@@ -1177,6 +1183,8 @@ static void ops_complete_reconstruct(void *stripe_head_ref) 
			set_bit(R5_UPTODATE, &dev->flags);

			if (fua)

				set_bit(R5_WantFUA, &dev->flags);

			if (sync)

				set_bit(R5_SyncIO, &dev->flags);

		}

	}

drivers/md/raid5.h

+1 −0
Original line number Diff line number Diff line
@@ -285,6 +285,7 @@ enum r5dev_flags { 
			 */

	R5_Wantdrain,	/* dev->towrite needs to be drained */

	R5_WantFUA,	/* Write should be FUA */

	R5_SyncIO,	/* The IO is sync */

	R5_WriteError,	/* got a write error - need to record it */

	R5_MadeGood,	/* A bad block has been fixed by writing to it */

	R5_ReadRepl,	/* Will/did read from replacement rather than orig */