md: raid5: check stripe cache is large enough in start_reshape
In reshape cases that do not change the number of devices,
start_reshape is called without first calling check_reshape.
Currently, the check that the stripe_cache is large enough is
only done in check_reshape. It should be in start_reshape too.
Signed-off-by: NeilBrown <neilb@suse.de>
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 0093441..b84766e 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -4845,6 +4845,29 @@
return 0;
}
+static int check_stripe_cache(mddev_t *mddev)
+{
+ /* Can only proceed if there are plenty of stripe_heads.
+ * We need a minimum of one full stripe,, and for sensible progress
+ * it is best to have about 4 times that.
+ * If we require 4 times, then the default 256 4K stripe_heads will
+ * allow for chunk sizes up to 256K, which is probably OK.
+ * If the chunk size is greater, user-space should request more
+ * stripe_heads first.
+ */
+ raid5_conf_t *conf = mddev->private;
+ if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
+ > conf->max_nr_stripes ||
+ ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
+ > conf->max_nr_stripes) {
+ printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n",
+ ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
+ / STRIPE_SIZE)*4);
+ return 0;
+ }
+ return 1;
+}
+
static int raid5_check_reshape(mddev_t *mddev)
{
raid5_conf_t *conf = mddev->private;
@@ -4871,24 +4894,8 @@
return -EINVAL;
}
- /* Can only proceed if there are plenty of stripe_heads.
- * We need a minimum of one full stripe,, and for sensible progress
- * it is best to have about 4 times that.
- * If we require 4 times, then the default 256 4K stripe_heads will
- * allow for chunk sizes up to 256K, which is probably OK.
- * If the chunk size is greater, user-space should request more
- * stripe_heads first.
- */
- if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
- > conf->max_nr_stripes ||
- ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
- > conf->max_nr_stripes) {
- printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n",
- (max(mddev->chunk_sectors << 9,
- mddev->new_chunk_sectors << 9)
- / STRIPE_SIZE)*4);
+ if (!check_stripe_cache(mddev))
return -ENOSPC;
- }
return resize_stripes(conf, conf->raid_disks + mddev->delta_disks);
}
@@ -4904,6 +4911,9 @@
if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
return -EBUSY;
+ if (!check_stripe_cache(mddev))
+ return -ENOSPC;
+
list_for_each_entry(rdev, &mddev->disks, same_set)
if (rdev->raid_disk < 0 &&
!test_bit(Faulty, &rdev->flags))