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: Shaohua Li <shli@fusionio.com>
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 962c8f4..7bfd59b 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -539,6 +539,8 @@
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 @@
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 @@
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 @@
set_bit(R5_UPTODATE, &dev->flags);
if (fua)
set_bit(R5_WantFUA, &dev->flags);
+ if (sync)
+ set_bit(R5_SyncIO, &dev->flags);
}
}
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index c6bdfa0..2164021 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -285,6 +285,7 @@
*/
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 */