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/raid0.c b/drivers/md/raid0.c
index 9aebb4c..bb0df6a 100644
--- a/drivers/md/raid0.c
+++ b/drivers/md/raid0.c
@@ -263,12 +263,25 @@
return max;
}
+static sector_t raid0_size(mddev_t *mddev, sector_t sectors, int raid_disks)
+{
+ sector_t array_sectors = 0;
+ mdk_rdev_t *rdev;
+
+ WARN_ONCE(sectors || raid_disks,
+ "%s does not support generic reshape\n", __func__);
+
+ list_for_each_entry(rdev, &mddev->disks, same_set)
+ array_sectors += rdev->sectors;
+
+ return array_sectors;
+}
+
static int raid0_run (mddev_t *mddev)
{
unsigned cur=0, i=0, nb_zone;
s64 sectors;
raid0_conf_t *conf;
- mdk_rdev_t *rdev;
if (mddev->chunk_size == 0) {
printk(KERN_ERR "md/raid0: non-zero chunk size required.\n");
@@ -293,9 +306,7 @@
goto out_free_conf;
/* calculate array device size */
- mddev->array_sectors = 0;
- list_for_each_entry(rdev, &mddev->disks, same_set)
- mddev->array_sectors += rdev->sectors;
+ mddev->array_sectors = raid0_size(mddev, 0, 0);
printk(KERN_INFO "raid0 : md_size is %llu sectors.\n",
(unsigned long long)mddev->array_sectors);
@@ -511,6 +522,7 @@
.run = raid0_run,
.stop = raid0_stop,
.status = raid0_status,
+ .size = raid0_size,
};
static int __init raid0_init (void)