md: add 'size' as a personality method
In preparation for giving userspace control over ->array_sectors we need
to be able to retrieve the 'default' size, and the 'anticipated' size
when a reshape is requested. For personalities that do not reshape emit
a warning if anything but the default size is requested.
In the raid5 case we need to update ->previous_raid_disks to make the
new 'default' size available.
Reviewed-by: Andre Noll <maan@systemlinux.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/drivers/md/multipath.c b/drivers/md/multipath.c
index 87accf7..a3f6d86 100644
--- a/drivers/md/multipath.c
+++ b/drivers/md/multipath.c
@@ -406,6 +406,14 @@
spin_unlock_irqrestore(&conf->device_lock, flags);
}
+static sector_t multipath_size(mddev_t *mddev, sector_t sectors, int raid_disks)
+{
+ WARN_ONCE(sectors || raid_disks,
+ "%s does not support generic reshape\n", __func__);
+
+ return mddev->dev_sectors;
+}
+
static int multipath_run (mddev_t *mddev)
{
multipath_conf_t *conf;
@@ -502,7 +510,7 @@
/*
* Ok, everything is just fine now
*/
- mddev->array_sectors = mddev->dev_sectors;
+ mddev->array_sectors = multipath_size(mddev, 0, 0);
mddev->queue->unplug_fn = multipath_unplug;
mddev->queue->backing_dev_info.congested_fn = multipath_congested;
@@ -547,6 +555,7 @@
.error_handler = multipath_error,
.hot_add_disk = multipath_add_disk,
.hot_remove_disk= multipath_remove_disk,
+ .size = multipath_size,
};
static int __init multipath_init (void)