[alsa-devel] [PATCH 39/39] ALSA: seq: optimize query_next_port function to new design

[Takashi Sakamoto]

In former commit, actual operations of each ioctl command get argument
in kernel space. Copying from/to user space is performed outside of
the function.

This commit optimizes to the new design.

Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>
---
 sound/core/seq/seq_clientmgr.c | 19 +++++++------------
 1 file changed, 7 insertions(+), 12 deletions(-)

diff --git a/sound/core/seq/seq_clientmgr.c b/sound/core/seq/seq_clientmgr.c
index 0f840ca..6bc29b5 100644
--- a/sound/core/seq/seq_clientmgr.c
+++ b/sound/core/seq/seq_clientmgr.c
@@ -2014,35 +2014,30 @@ static int seq_ioctl_query_next_client(struct snd_seq_client *client, void *arg)
 /* 
  * query next port
  */
-static int seq_ioctl_query_next_port(struct snd_seq_client *client,
-				     void __user *arg)
+static int seq_ioctl_query_next_port(struct snd_seq_client *client, void *arg)
 {
+	struct snd_seq_port_info *info = arg;
 	struct snd_seq_client *cptr;
 	struct snd_seq_client_port *port = NULL;
-	struct snd_seq_port_info info;
 
-	if (copy_from_user(&info, arg, sizeof(info)))
-		return -EFAULT;
-	cptr = snd_seq_client_use_ptr(info.addr.client);
+	cptr = snd_seq_client_use_ptr(info->addr.client);
 	if (cptr == NULL)
 		return -ENXIO;
 
 	/* search for next port */
-	info.addr.port++;
-	port = snd_seq_port_query_nearest(cptr, &info);
+	info->addr.port++;
+	port = snd_seq_port_query_nearest(cptr, info);
 	if (port == NULL) {
 		snd_seq_client_unlock(cptr);
 		return -ENOENT;
 	}
 
 	/* get port info */
-	info.addr = port->addr;
-	snd_seq_get_port_info(port, &info);
+	info->addr = port->addr;
+	snd_seq_get_port_info(port, info);
 	snd_seq_port_unlock(port);
 	snd_seq_client_unlock(cptr);
 
-	if (copy_to_user(arg, &info, sizeof(info)))
-		return -EFAULT;
 	return 0;
 }
 
-- 
2.7.4