firewire: convert client_list_lock to mutex

So far it is only taken in non-atomic contexts.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>

drivers/firewire/fw-cdev.c

@@ -24,6 +24,7 @@
 #include <linux/errno.h>
 #include <linux/device.h>
 #include <linux/vmalloc.h>
+#include <linux/mutex.h>
 #include <linux/poll.h>
 #include <linux/preempt.h>
 #include <linux/time.h>
@@ -108,7 +109,6 @@ static int fw_device_op_open(struct inode *inode, struct file *file)
 {
 	struct fw_device *device;
 	struct client *client;
-	unsigned long flags;
 
 	device = fw_device_get_by_devt(inode->i_rdev);
 	if (device == NULL)
@@ -133,9 +133,9 @@ static int fw_device_op_open(struct inode *inode, struct file *file)
 
 	file->private_data = client;
 
-	spin_lock_irqsave(&device->client_list_lock, flags);
+	mutex_lock(&device->client_list_mutex);
 	list_add_tail(&client->link, &device->client_list);
-	spin_unlock_irqrestore(&device->client_list_lock, flags);
+	mutex_unlock(&device->client_list_mutex);
 
 	return 0;
 }
@@ -232,14 +232,11 @@ for_each_client(struct fw_device *device,
 		void (*callback)(struct client *client))
 {
 	struct client *c;
-	unsigned long flags;
-
-	spin_lock_irqsave(&device->client_list_lock, flags);
 
+	mutex_lock(&device->client_list_mutex);
 	list_for_each_entry(c, &device->client_list, link)
 		callback(c);
-
-	spin_unlock_irqrestore(&device->client_list_lock, flags);
+	mutex_unlock(&device->client_list_mutex);
 }
 
 static void
@@ -247,7 +244,7 @@ queue_bus_reset_event(struct client *client)
 {
 	struct bus_reset *bus_reset;
 
-	bus_reset = kzalloc(sizeof(*bus_reset), GFP_ATOMIC);
+	bus_reset = kzalloc(sizeof(*bus_reset), GFP_KERNEL);
 	if (bus_reset == NULL) {
 		fw_notify("Out of memory when allocating bus reset event\n");
 		return;
@@ -988,7 +985,6 @@ static int fw_device_op_release(struct inode *inode, struct file *file)
 	struct client *client = file->private_data;
 	struct event *e, *next_e;
 	struct client_resource *r, *next_r;
-	unsigned long flags;
 
 	if (client->buffer.pages)
 		fw_iso_buffer_destroy(&client->buffer, client->device->card);
@@ -1007,9 +1003,9 @@ static int fw_device_op_release(struct inode *inode, struct file *file)
 	list_for_each_entry_safe(e, next_e, &client->event_list, link)
 		kfree(e);
 
-	spin_lock_irqsave(&client->device->client_list_lock, flags);
+	mutex_lock(&client->device->client_list_mutex);
 	list_del(&client->link);
-	spin_unlock_irqrestore(&client->device->client_list_lock, flags);
+	mutex_unlock(&client->device->client_list_mutex);
 
 	fw_device_put(client->device);
 	kfree(client);

drivers/firewire/fw-device.c

@@ -27,6 +27,7 @@
 #include <linux/idr.h>
 #include <linux/jiffies.h>
 #include <linux/string.h>
+#include <linux/mutex.h>
 #include <linux/rwsem.h>
 #include <linux/semaphore.h>
 #include <linux/spinlock.h>
@@ -1005,7 +1006,7 @@ void fw_node_event(struct fw_card *card, struct fw_node *node, int event)
 		device->node = fw_node_get(node);
 		device->node_id = node->node_id;
 		device->generation = card->generation;
-		spin_lock_init(&device->client_list_lock);
+		mutex_init(&device->client_list_mutex);
 		INIT_LIST_HEAD(&device->client_list);
 
 		/*

drivers/firewire/fw-device.h

@@ -23,7 +23,7 @@
 #include <linux/cdev.h>
 #include <linux/idr.h>
 #include <linux/rwsem.h>
-#include <linux/spinlock.h>
+#include <linux/mutex.h>
 #include <asm/atomic.h>
 
 enum fw_device_state {
@@ -65,9 +65,10 @@ struct fw_device {
 	bool cmc;
 	struct fw_card *card;
 	struct device device;
-	/* to prevent deadlocks, never take this lock with card->lock held */
-	spinlock_t client_list_lock;
+
+	struct mutex client_list_mutex;
 	struct list_head client_list;
+
 	u32 *config_rom;
 	size_t config_rom_length;
 	int config_rom_retries;