@@ -2091,6 +2091,14 @@ static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
unsigned long cpu;
int err = 0;
+ /*
+ * Never shrink. And mddev_suspend() could deadlock if this is called
+ * from raid5d. In that case, scribble_disks and scribble_sectors
+ * should equal to new_disks and new_sectors
+ */
+ if (conf->scribble_disks >= new_disks &&
+ conf->scribble_sectors >= new_sectors)
+ return 0;
mddev_suspend(conf->mddev);
get_online_cpus();
for_each_present_cpu(cpu) {
@@ -2112,6 +2120,10 @@ static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
}
put_online_cpus();
mddev_resume(conf->mddev);
+ if (!err) {
+ conf->scribble_disks = new_disks;
+ conf->scribble_sectors = new_sectors;
+ }
return err;
}
@@ -6379,6 +6391,12 @@ static int raid5_alloc_percpu(struct r5conf *conf)
}
put_online_cpus();
+ if (!err) {
+ conf->scribble_disks = max(conf->raid_disks,
+ conf->previous_raid_disks);
+ conf->scribble_sectors = max(conf->chunk_sectors,
+ conf->prev_chunk_sectors);
+ }
return err;
}
@@ -501,6 +501,8 @@ struct r5conf {
* conversions
*/
} __percpu *percpu;
+ int scribble_disks;
+ int scribble_sectors;
#ifdef CONFIG_HOTPLUG_CPU
struct notifier_block cpu_notify;
#endif