[PATCH v4 2/5] media: Unify IOCTL handler calling

[Sakari Ailus <sakari.ailus@linux.intel.com>]

Each IOCTL handler can be listed in an array instead of using a large and
cumbersome switch. Do that.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Acked-by: Hans Verkuil <hans.verkuil@cisco.com>
---
 drivers/media/media-device.c | 80 ++++++++++++--------------------------------
 1 file changed, 22 insertions(+), 58 deletions(-)

diff --git a/drivers/media/media-device.c b/drivers/media/media-device.c
index aedd64e..cc6c566 100644
--- a/drivers/media/media-device.c
+++ b/drivers/media/media-device.c
@@ -419,20 +419,24 @@ static long media_device_get_topology(struct media_device *mdev,
 	return 0;
 }
 
-#define MEDIA_IOC(__cmd) \
-	[_IOC_NR(MEDIA_IOC_##__cmd)] = { .cmd = MEDIA_IOC_##__cmd }
+#define MEDIA_IOC(__cmd, func)						\
+	[_IOC_NR(MEDIA_IOC_##__cmd)] = {				\
+		.cmd = MEDIA_IOC_##__cmd,				\
+		.fn = (long (*)(struct media_device *, void __user *))func,    \
+	}
 
 /* the table is indexed by _IOC_NR(cmd) */
 struct media_ioctl_info {
 	unsigned int cmd;
+	long (*fn)(struct media_device *dev, void __user *arg);
 };
 
 static const struct media_ioctl_info ioctl_info[] = {
-	MEDIA_IOC(DEVICE_INFO),
-	MEDIA_IOC(ENUM_ENTITIES),
-	MEDIA_IOC(ENUM_LINKS),
-	MEDIA_IOC(SETUP_LINK),
-	MEDIA_IOC(G_TOPOLOGY),
+	MEDIA_IOC(DEVICE_INFO, media_device_get_info),
+	MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities),
+	MEDIA_IOC(ENUM_LINKS, media_device_enum_links),
+	MEDIA_IOC(SETUP_LINK, media_device_setup_link),
+	MEDIA_IOC(G_TOPOLOGY, media_device_get_topology),
 };
 
 static inline long is_valid_ioctl(const struct media_ioctl_info *info,
@@ -448,42 +452,17 @@ static long __media_device_ioctl(
 {
 	struct media_devnode *devnode = media_devnode_data(filp);
 	struct media_device *dev = devnode->media_dev;
+	const struct media_ioctl_info *info;
 	long ret;
 
 	ret = is_valid_ioctl(info_array, cmd);
 	if (ret)
 		return ret;
 
+	info = &info_array[_IOC_NR(cmd)];
+
 	mutex_lock(&dev->graph_mutex);
-	switch (cmd) {
-	case MEDIA_IOC_DEVICE_INFO:
-		ret = media_device_get_info(dev,
-				(struct media_device_info __user *)arg);
-		break;
-
-	case MEDIA_IOC_ENUM_ENTITIES:
-		ret = media_device_enum_entities(dev,
-				(struct media_entity_desc __user *)arg);
-		break;
-
-	case MEDIA_IOC_ENUM_LINKS:
-		ret = media_device_enum_links(dev,
-				(struct media_links_enum __user *)arg);
-		break;
-
-	case MEDIA_IOC_SETUP_LINK:
-		ret = media_device_setup_link(dev,
-				(struct media_link_desc __user *)arg);
-		break;
-
-	case MEDIA_IOC_G_TOPOLOGY:
-		ret = media_device_get_topology(dev,
-				(struct media_v2_topology __user *)arg);
-		break;
-
-	default:
-		ret = -ENOIOCTLCMD;
-	}
+	ret = info->fn(dev, arg);
 	mutex_unlock(&dev->graph_mutex);
 
 	return ret;
@@ -527,20 +506,16 @@ static long media_device_enum_links32(struct media_device *mdev,
 #define MEDIA_IOC_ENUM_LINKS32		_IOWR('|', 0x02, struct media_links_enum32)
 
 static const struct media_ioctl_info compat_ioctl_info[] = {
-	MEDIA_IOC(DEVICE_INFO),
-	MEDIA_IOC(ENUM_ENTITIES),
-	MEDIA_IOC(ENUM_LINKS32),
-	MEDIA_IOC(SETUP_LINK),
-	MEDIA_IOC(G_TOPOLOGY),
+	MEDIA_IOC(DEVICE_INFO, media_device_get_info),
+	MEDIA_IOC(ENUM_ENTITIES, media_device_enum_entities),
+	MEDIA_IOC(ENUM_LINKS32, media_device_enum_links32),
+	MEDIA_IOC(SETUP_LINK, media_device_setup_link),
+	MEDIA_IOC(G_TOPOLOGY, media_device_get_topology),
 };
 
 static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
 				      unsigned long arg)
 {
-	struct media_devnode *devnode = media_devnode_data(filp);
-	struct media_device *dev = devnode->media_dev;
-	long ret;
-
 	/*
 	 * The number of supported IOCTLs is the same for both regular and
 	 * compat cases. Instead of passing the sizes around, ensure that
@@ -548,19 +523,8 @@ static long media_device_compat_ioctl(struct file *filp, unsigned int cmd,
 	 */
 	BUILD_BUG_ON(ARRAY_SIZE(ioctl_info) != ARRAY_SIZE(compat_ioctl_info));
 
-	switch (cmd) {
-	case MEDIA_IOC_ENUM_LINKS32:
-		mutex_lock(&dev->graph_mutex);
-		ret = media_device_enum_links32(dev,
-				(struct media_links_enum32 __user *)arg);
-		mutex_unlock(&dev->graph_mutex);
-		break;
-
-	default:
-		return media_device_ioctl(filp, cmd, arg);
-	}
-
-	return ret;
+	return __media_device_ioctl(
+		filp, cmd, (void __user *)arg, compat_ioctl_info);
 }
 #endif /* CONFIG_COMPAT */
 
-- 
2.7.4