Some people use the md driver on laptops and use the suspend and
resume functionality. Since it is essential that submitting of
new I/O requests stops before a hibernation image is created,
interrupt the md resync and reshape actions if the system is
being frozen. Note: the resync and reshape will restart after
the system is resumed and a message similar to the following
will appear in the system log:
md: md0: data-check interrupted.
Additionally, only allow resync or reshape activity to be
started after system freezing is over.
Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx>
Cc: Shaohua Li <shli@xxxxxxxxxx>
Cc: linux-raid@xxxxxxxxxxxxxxx
Cc: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Hannes Reinecke <hare@xxxxxxxx>
Cc: Johannes Thumshirn <jthumshirn@xxxxxxx>
---
drivers/md/md.c | 37 ++++++++++++++++++++++++++++++++++++-
1 file changed, 36 insertions(+), 1 deletion(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 3f7426120a3b..a2cf2a93b0cb 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -66,6 +66,7 @@
#include <linux/raid/md_u.h>
#include <linux/slab.h>
#include <linux/percpu-refcount.h>
+#include <linux/suspend.h>
#include <trace/events/block.h>
#include "md.h"
@@ -7450,7 +7451,8 @@ static int md_thread(void *arg)
wait_event_interruptible_timeout
(thread->wqueue,
- test_bit(THREAD_WAKEUP, &thread->flags)
+ (test_bit(THREAD_WAKEUP, &thread->flags) &&
+ atomic_read(&system_freezing_cnt) == 0)
|| kthread_should_stop() || kthread_should_park(),
thread->timeout);
@@ -8961,6 +8963,37 @@ static void md_stop_all_writes(void)
mdelay(1000*1);
}
+/*
+ * Ensure that neither resyncing nor reshaping occurs while the system is
+ * frozen.
+ */
+static int md_notify_pm(struct notifier_block *bl, unsigned long state,
+ void *unused)
+{
+ struct mddev *mddev;
+ struct list_head *tmp;
+
+ pr_debug("%s: state = %ld; system_freezing_cnt = %d\n", __func__, state,
+ atomic_read(&system_freezing_cnt));
+
+ switch (state) {
+ case PM_HIBERNATION_PREPARE:
+ md_stop_all_writes();
+ break;
+ case PM_POST_HIBERNATION:
+ rcu_read_lock();
+ for_each_mddev(mddev, tmp)
+ wake_up(&mddev->thread->wqueue);
+ rcu_read_unlock();
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
+static struct notifier_block md_pm_notifier = {
+ .notifier_call = md_notify_pm,
+};
+
static int md_notify_reboot(struct notifier_block *this,
unsigned long code, void *x)
{
@@ -9007,6 +9040,7 @@ static int __init md_init(void)
md_probe, NULL, NULL);
register_reboot_notifier(&md_reboot_notifier);
+ register_pm_notifier(&md_pm_notifier);
raid_table_header = register_sysctl_table(raid_root_table);
md_geninit();
@@ -9246,6 +9280,7 @@ static __exit void md_exit(void)
unregister_blkdev(MD_MAJOR,"md");
unregister_blkdev(mdp_major, "mdp");
+ unregister_pm_notifier(&md_pm_notifier);
unregister_reboot_notifier(&md_reboot_notifier);
unregister_sysctl_table(raid_table_header);
--
2.14.1
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