raid5: track overwrite disk count
Track overwrite disk count, so we can know if a stripe is a full stripe write.
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 49b0f23..e801c66 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -553,6 +553,7 @@
}
if (read_seqcount_retry(&conf->gen_lock, seq))
goto retry;
+ sh->overwrite_disks = 0;
insert_hash(conf, sh);
sh->cpu = smp_processor_id();
set_bit(STRIPE_BATCH_READY, &sh->state);
@@ -710,6 +711,12 @@
return sh;
}
+static bool is_full_stripe_write(struct stripe_head *sh)
+{
+ BUG_ON(sh->overwrite_disks > (sh->disks - sh->raid_conf->max_degraded));
+ return sh->overwrite_disks == (sh->disks - sh->raid_conf->max_degraded);
+}
+
/* Determine if 'data_offset' or 'new_data_offset' should be used
* in this stripe_head.
*/
@@ -1413,6 +1420,7 @@
spin_lock_irq(&sh->stripe_lock);
chosen = dev->towrite;
dev->towrite = NULL;
+ sh->overwrite_disks = 0;
BUG_ON(dev->written);
wbi = dev->written = chosen;
spin_unlock_irq(&sh->stripe_lock);
@@ -2700,7 +2708,8 @@
sector = bio_end_sector(bi);
}
if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
- set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags);
+ if (!test_and_set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags))
+ sh->overwrite_disks++;
}
pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
@@ -2772,6 +2781,7 @@
/* fail all writes first */
bi = sh->dev[i].towrite;
sh->dev[i].towrite = NULL;
+ sh->overwrite_disks = 0;
spin_unlock_irq(&sh->stripe_lock);
if (bi)
bitmap_end = 1;
@@ -4630,12 +4640,14 @@
}
set_bit(STRIPE_DISCARD, &sh->state);
finish_wait(&conf->wait_for_overlap, &w);
+ sh->overwrite_disks = 0;
for (d = 0; d < conf->raid_disks; d++) {
if (d == sh->pd_idx || d == sh->qd_idx)
continue;
sh->dev[d].towrite = bi;
set_bit(R5_OVERWRITE, &sh->dev[d].flags);
raid5_inc_bi_active_stripes(bi);
+ sh->overwrite_disks++;
}
spin_unlock_irq(&sh->stripe_lock);
if (conf->mddev->bitmap) {
diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h
index 37644e3..4cc1a48 100644
--- a/drivers/md/raid5.h
+++ b/drivers/md/raid5.h
@@ -210,6 +210,10 @@
atomic_t count; /* nr of active thread/requests */
int bm_seq; /* sequence number for bitmap flushes */
int disks; /* disks in stripe */
+ int overwrite_disks; /* total overwrite disks in stripe,
+ * this is only checked when stripe
+ * has STRIPE_BATCH_READY
+ */
enum check_states check_state;
enum reconstruct_states reconstruct_state;
spinlock_t stripe_lock;