md/raid5: unite fetch_block5 and fetch_block6
Provided that ->failed_num[1] is not a valid device number (which is
easily achieved) fetch_block6 provides all the functionality of
fetch_block5.
So remove the latter and rename the former to simply "fetch_block".
Then handle_stripe_fill5 and handle_stripe_fill6 become the same and
can similarly be united.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index a3d7cd9..a63a6791 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2308,17 +2308,18 @@
md_wakeup_thread(conf->mddev->thread);
}
-/* fetch_block5 - checks the given member device to see if its data needs
+/* fetch_block - checks the given member device to see if its data needs
* to be read or computed to satisfy a request.
*
* Returns 1 when no more member devices need to be checked, otherwise returns
- * 0 to tell the loop in handle_stripe_fill5 to continue
+ * 0 to tell the loop in handle_stripe_fill to continue
*/
-static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s,
- int disk_idx, int disks)
+static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
+ int disk_idx, int disks)
{
struct r5dev *dev = &sh->dev[disk_idx];
- struct r5dev *failed_dev = &sh->dev[s->failed_num[0]];
+ struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]],
+ &sh->dev[s->failed_num[1]] };
/* is the data in this block needed, and can we get it? */
if (!test_bit(R5_LOCKED, &dev->flags) &&
@@ -2326,81 +2327,11 @@
(dev->toread ||
(dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
s->syncing || s->expanding ||
- (s->failed && failed_dev->toread) ||
- (s->failed && failed_dev->towrite &&
- !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) {
- /* We would like to get this block, possibly by computing it,
- * otherwise read it if the backing disk is insync
- */
- if ((s->uptodate == disks - 1) &&
- (s->failed && disk_idx == s->failed_num[0])) {
- set_bit(STRIPE_COMPUTE_RUN, &sh->state);
- set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
- set_bit(R5_Wantcompute, &dev->flags);
- sh->ops.target = disk_idx;
- sh->ops.target2 = -1;
- s->req_compute = 1;
- /* Careful: from this point on 'uptodate' is in the eye
- * of raid_run_ops which services 'compute' operations
- * before writes. R5_Wantcompute flags a block that will
- * be R5_UPTODATE by the time it is needed for a
- * subsequent operation.
- */
- s->uptodate++;
- return 1; /* uptodate + compute == disks */
- } else if (test_bit(R5_Insync, &dev->flags)) {
- set_bit(R5_LOCKED, &dev->flags);
- set_bit(R5_Wantread, &dev->flags);
- s->locked++;
- pr_debug("Reading block %d (sync=%d)\n", disk_idx,
- s->syncing);
- }
- }
-
- return 0;
-}
-
-/**
- * handle_stripe_fill5 - read or compute data to satisfy pending requests.
- */
-static void handle_stripe_fill5(struct stripe_head *sh,
- struct stripe_head_state *s, int disks)
-{
- int i;
-
- /* look for blocks to read/compute, skip this if a compute
- * is already in flight, or if the stripe contents are in the
- * midst of changing due to a write
- */
- if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
- !sh->reconstruct_state)
- for (i = disks; i--; )
- if (fetch_block5(sh, s, i, disks))
- break;
- set_bit(STRIPE_HANDLE, &sh->state);
-}
-
-/* fetch_block6 - checks the given member device to see if its data needs
- * to be read or computed to satisfy a request.
- *
- * Returns 1 when no more member devices need to be checked, otherwise returns
- * 0 to tell the loop in handle_stripe_fill6 to continue
- */
-static int fetch_block6(struct stripe_head *sh, struct stripe_head_state *s,
- int disk_idx, int disks)
-{
- struct r5dev *dev = &sh->dev[disk_idx];
- struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]],
- &sh->dev[s->failed_num[1]] };
-
- if (!test_bit(R5_LOCKED, &dev->flags) &&
- !test_bit(R5_UPTODATE, &dev->flags) &&
- (dev->toread ||
- (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) ||
- s->syncing || s->expanding ||
(s->failed >= 1 && fdev[0]->toread) ||
(s->failed >= 2 && fdev[1]->toread) ||
- (s->failed && s->to_write)) {
+ (sh->raid_conf->level <= 5 && s->failed && fdev[0]->towrite &&
+ !test_bit(R5_OVERWRITE, &fdev[0]->flags)) ||
+ (sh->raid_conf->level == 6 && s->failed && s->to_write))) {
/* we would like to get this block, possibly by computing it,
* otherwise read it if the backing disk is insync
*/
@@ -2420,6 +2351,12 @@
sh->ops.target = disk_idx;
sh->ops.target2 = -1; /* no 2nd target */
s->req_compute = 1;
+ /* Careful: from this point on 'uptodate' is in the eye
+ * of raid_run_ops which services 'compute' operations
+ * before writes. R5_Wantcompute flags a block that will
+ * be R5_UPTODATE by the time it is needed for a
+ * subsequent operation.
+ */
s->uptodate++;
return 1;
} else if (s->uptodate == disks-2 && s->failed >= 2) {
@@ -2460,11 +2397,11 @@
}
/**
- * handle_stripe_fill6 - read or compute data to satisfy pending requests.
+ * handle_stripe_fill - read or compute data to satisfy pending requests.
*/
-static void handle_stripe_fill6(struct stripe_head *sh,
- struct stripe_head_state *s,
- int disks)
+static void handle_stripe_fill(struct stripe_head *sh,
+ struct stripe_head_state *s,
+ int disks)
{
int i;
@@ -2475,7 +2412,7 @@
if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
!sh->reconstruct_state)
for (i = disks; i--; )
- if (fetch_block6(sh, s, i, disks))
+ if (fetch_block(sh, s, i, disks))
break;
set_bit(STRIPE_HANDLE, &sh->state);
}
@@ -3122,7 +3059,7 @@
*/
if (s->to_read || s->non_overwrite ||
(s->syncing && (s->uptodate + s->compute < disks)) || s->expanding)
- handle_stripe_fill5(sh, s, disks);
+ handle_stripe_fill(sh, s, disks);
/* Now we check to see if any write operations have recently
* completed
@@ -3313,7 +3250,7 @@
*/
if (s->to_read || s->non_overwrite || (s->to_write && s->failed) ||
(s->syncing && (s->uptodate + s->compute < disks)) || s->expanding)
- handle_stripe_fill6(sh, s, disks);
+ handle_stripe_fill(sh, s, disks);
/* Now we check to see if any write operations have recently
* completed
@@ -3397,6 +3334,8 @@
s.syncing = test_bit(STRIPE_SYNCING, &sh->state);
s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state);
s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state);
+ s.failed_num[0] = -1;
+ s.failed_num[1] = -1;
if (conf->level == 6)
done = handle_stripe6(sh, &s);