[PATCH] cxl/mbox: Use guard() for mbox_mutex locking

[Davidlohr Bueso <dave@stgolabs.net>]

Use the new helpers and simplify the code. No change in
semantics.

Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
---
 drivers/cxl/core/memdev.c | 16 ++++++++--------
 drivers/cxl/pci.c         | 21 ++++++++-------------
 2 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
index 3db4e91170a8..0c9067ced7b3 100644
--- a/drivers/cxl/core/memdev.c
+++ b/drivers/cxl/core/memdev.c
@@ -138,10 +138,10 @@ static ssize_t security_state_show(struct device *dev,
 	int rc = 0;
 
 	/* sync with latest submission state */
-	mutex_lock(&cxl_mbox->mbox_mutex);
-	if (mds->security.sanitize_active)
-		rc = sysfs_emit(buf, "sanitize\n");
-	mutex_unlock(&cxl_mbox->mbox_mutex);
+	scoped_guard(mutex, &cxl_mbox->mbox_mutex) {
+		if (mds->security.sanitize_active)
+			rc = sysfs_emit(buf, "sanitize\n");
+	}
 	if (rc)
 		return rc;
 
@@ -1247,10 +1247,10 @@ static void sanitize_teardown_notifier(void *data)
 	 * Prevent new irq triggered invocations of the workqueue and
 	 * flush inflight invocations.
 	 */
-	mutex_lock(&cxl_mbox->mbox_mutex);
-	state = mds->security.sanitize_node;
-	mds->security.sanitize_node = NULL;
-	mutex_unlock(&cxl_mbox->mbox_mutex);
+	scoped_guard(mutex, &cxl_mbox->mbox_mutex) {
+		state = mds->security.sanitize_node;
+		mds->security.sanitize_node = NULL;
+	}
 
 	cancel_delayed_work_sync(&mds->security.poll_dwork);
 	sysfs_put(state);
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 95bf773aab14..3462cea6e61b 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -134,10 +134,11 @@ static irqreturn_t cxl_pci_mbox_irq(int irq, void *id)
 	reg = readq(cxlds->regs.mbox + CXLDEV_MBOX_BG_CMD_STATUS_OFFSET);
 	opcode = FIELD_GET(CXLDEV_MBOX_BG_CMD_COMMAND_OPCODE_MASK, reg);
 	if (opcode == CXL_MBOX_OP_SANITIZE) {
-		mutex_lock(&cxl_mbox->mbox_mutex);
-		if (mds->security.sanitize_node)
-			mod_delayed_work(system_percpu_wq, &mds->security.poll_dwork, 0);
-		mutex_unlock(&cxl_mbox->mbox_mutex);
+		scoped_guard(mutex, &cxl_mbox->mbox_mutex) {
+			if (mds->security.sanitize_node)
+				mod_delayed_work(system_percpu_wq,
+						 &mds->security.poll_dwork, 0);
+		}
 	} else {
 		/* short-circuit the wait in __cxl_pci_mbox_send_cmd() */
 		rcuwait_wake_up(&cxl_mbox->mbox_wait);
@@ -156,7 +157,7 @@ static void cxl_mbox_sanitize_work(struct work_struct *work)
 	struct cxl_dev_state *cxlds = &mds->cxlds;
 	struct cxl_mailbox *cxl_mbox = &cxlds->cxl_mbox;
 
-	mutex_lock(&cxl_mbox->mbox_mutex);
+	guard(mutex)(&cxl_mbox->mbox_mutex);
 	if (cxl_mbox_background_complete(cxlds)) {
 		mds->security.poll_tmo_secs = 0;
 		if (mds->security.sanitize_node)
@@ -170,7 +171,6 @@ static void cxl_mbox_sanitize_work(struct work_struct *work)
 		mds->security.poll_tmo_secs = min(15 * 60, timeout);
 		schedule_delayed_work(&mds->security.poll_dwork, timeout * HZ);
 	}
-	mutex_unlock(&cxl_mbox->mbox_mutex);
 }
 
 /**
@@ -377,13 +377,8 @@ static int __cxl_pci_mbox_send_cmd(struct cxl_mailbox *cxl_mbox,
 static int cxl_pci_mbox_send(struct cxl_mailbox *cxl_mbox,
 			     struct cxl_mbox_cmd *cmd)
 {
-	int rc;
-
-	mutex_lock(&cxl_mbox->mbox_mutex);
-	rc = __cxl_pci_mbox_send_cmd(cxl_mbox, cmd);
-	mutex_unlock(&cxl_mbox->mbox_mutex);
-
-	return rc;
+	guard(mutex)(&cxl_mbox->mbox_mutex);
+	return __cxl_pci_mbox_send_cmd(cxl_mbox, cmd);
 }
 
 static int cxl_pci_setup_mailbox(struct cxl_memdev_state *mds, bool irq_avail)
-- 
2.39.5