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Message-Id: <1394565130-24233-2-git-send-email-simon.guinot@sequanux.org>
Date: Tue, 11 Mar 2014 20:12:09 +0100
From: Simon Guinot <simon.guinot@...uanux.org>
To: Neil Brown <neilb@...e.de>
Cc: linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org,
Rémi Rérolle <remi.rerolle@...gate.com>,
Simon Guinot <simon.guinot@...uanux.org>
Subject: [PATCH 1/2] md: move up mddev locking functions
This patch slightly moves up the mddev locking functions. This allows
to use them from mddev_suspend().
Signed-off-by: Simon Guinot <simon.guinot@...uanux.org>
---
drivers/md/md.c | 135 ++++++++++++++++++++++++++++----------------------------
1 file changed, 67 insertions(+), 68 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 4ad5cc4e63e8..fb4296adae80 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -218,6 +218,73 @@ static void md_new_event_inintr(struct mddev *mddev)
static LIST_HEAD(all_mddevs);
static DEFINE_SPINLOCK(all_mddevs_lock);
+static inline int __must_check mddev_lock(struct mddev * mddev)
+{
+ return mutex_lock_interruptible(&mddev->reconfig_mutex);
+}
+
+/* Sometimes we need to take the lock in a situation where
+ * failure due to interrupts is not acceptable.
+ */
+static inline void mddev_lock_nointr(struct mddev * mddev)
+{
+ mutex_lock(&mddev->reconfig_mutex);
+}
+
+static inline int mddev_is_locked(struct mddev *mddev)
+{
+ return mutex_is_locked(&mddev->reconfig_mutex);
+}
+
+static inline int mddev_trylock(struct mddev * mddev)
+{
+ return mutex_trylock(&mddev->reconfig_mutex);
+}
+
+static struct attribute_group md_redundancy_group;
+
+static void mddev_unlock(struct mddev * mddev)
+{
+ if (mddev->to_remove) {
+ /* These cannot be removed under reconfig_mutex as
+ * an access to the files will try to take reconfig_mutex
+ * while holding the file unremovable, which leads to
+ * a deadlock.
+ * So hold set sysfs_active while the remove in happeing,
+ * and anything else which might set ->to_remove or my
+ * otherwise change the sysfs namespace will fail with
+ * -EBUSY if sysfs_active is still set.
+ * We set sysfs_active under reconfig_mutex and elsewhere
+ * test it under the same mutex to ensure its correct value
+ * is seen.
+ */
+ struct attribute_group *to_remove = mddev->to_remove;
+ mddev->to_remove = NULL;
+ mddev->sysfs_active = 1;
+ mutex_unlock(&mddev->reconfig_mutex);
+
+ if (mddev->kobj.sd) {
+ if (to_remove != &md_redundancy_group)
+ sysfs_remove_group(&mddev->kobj, to_remove);
+ if (mddev->pers == NULL ||
+ mddev->pers->sync_request == NULL) {
+ sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
+ if (mddev->sysfs_action)
+ sysfs_put(mddev->sysfs_action);
+ mddev->sysfs_action = NULL;
+ }
+ }
+ mddev->sysfs_active = 0;
+ } else
+ mutex_unlock(&mddev->reconfig_mutex);
+
+ /* As we've dropped the mutex we need a spinlock to
+ * make sure the thread doesn't disappear
+ */
+ spin_lock(&pers_lock);
+ md_wakeup_thread(mddev->thread);
+ spin_unlock(&pers_lock);
+}
/*
* iterates through all used mddevs in the system.
@@ -562,74 +629,6 @@ static struct mddev * mddev_find(dev_t unit)
goto retry;
}
-static inline int __must_check mddev_lock(struct mddev * mddev)
-{
- return mutex_lock_interruptible(&mddev->reconfig_mutex);
-}
-
-/* Sometimes we need to take the lock in a situation where
- * failure due to interrupts is not acceptable.
- */
-static inline void mddev_lock_nointr(struct mddev * mddev)
-{
- mutex_lock(&mddev->reconfig_mutex);
-}
-
-static inline int mddev_is_locked(struct mddev *mddev)
-{
- return mutex_is_locked(&mddev->reconfig_mutex);
-}
-
-static inline int mddev_trylock(struct mddev * mddev)
-{
- return mutex_trylock(&mddev->reconfig_mutex);
-}
-
-static struct attribute_group md_redundancy_group;
-
-static void mddev_unlock(struct mddev * mddev)
-{
- if (mddev->to_remove) {
- /* These cannot be removed under reconfig_mutex as
- * an access to the files will try to take reconfig_mutex
- * while holding the file unremovable, which leads to
- * a deadlock.
- * So hold set sysfs_active while the remove in happeing,
- * and anything else which might set ->to_remove or my
- * otherwise change the sysfs namespace will fail with
- * -EBUSY if sysfs_active is still set.
- * We set sysfs_active under reconfig_mutex and elsewhere
- * test it under the same mutex to ensure its correct value
- * is seen.
- */
- struct attribute_group *to_remove = mddev->to_remove;
- mddev->to_remove = NULL;
- mddev->sysfs_active = 1;
- mutex_unlock(&mddev->reconfig_mutex);
-
- if (mddev->kobj.sd) {
- if (to_remove != &md_redundancy_group)
- sysfs_remove_group(&mddev->kobj, to_remove);
- if (mddev->pers == NULL ||
- mddev->pers->sync_request == NULL) {
- sysfs_remove_group(&mddev->kobj, &md_redundancy_group);
- if (mddev->sysfs_action)
- sysfs_put(mddev->sysfs_action);
- mddev->sysfs_action = NULL;
- }
- }
- mddev->sysfs_active = 0;
- } else
- mutex_unlock(&mddev->reconfig_mutex);
-
- /* As we've dropped the mutex we need a spinlock to
- * make sure the thread doesn't disappear
- */
- spin_lock(&pers_lock);
- md_wakeup_thread(mddev->thread);
- spin_unlock(&pers_lock);
-}
-
static struct md_rdev * find_rdev_nr(struct mddev *mddev, int nr)
{
struct md_rdev *rdev;
--
1.8.5.3
--
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