sound: push BKL into open functions

This moves the lock_kernel() call from soundcore_open
to the individual OSS device drivers, where we can deal
with it one driver at a time if needed, or just kill
off the drivers.

All core components in ALSA already provide
adequate locking in their open()-functions
and do not require the big kernel lock, so
there is no need to add the BKL there.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 22 insertions, 6 deletions

diff --git a/sound/oss/dmasound/dmasound_core.c b/sound/oss/dmasound/dmasound_core.c
index 3f3c3f71db4b..5a4f38c0f480 100644
--- a/sound/oss/dmasound/dmasound_core.c
+++ b/sound/oss/dmasound/dmasound_core.c
@@ -323,9 +323,13 @@ static struct {
 
 static int mixer_open(struct inode *inode, struct file *file)
 {
-        if (!try_module_get(dmasound.mach.owner))
+        lock_kernel();
+        if (!try_module_get(dmasound.mach.owner)) {
+                unlock_kernel();
                 return -ENODEV;
+        }
         mixer.busy = 1;
+        unlock_kernel();
         return 0;
 }
 
@@ -737,8 +741,11 @@ static int sq_open(struct inode *inode, struct file *file)
 {
         int rc;
 
-        if (!try_module_get(dmasound.mach.owner))
+        lock_kernel();
+        if (!try_module_get(dmasound.mach.owner)) {
+                unlock_kernel();
                 return -ENODEV;
+        }
 
         rc = write_sq_open(file); /* checks the f_mode */
         if (rc)
@@ -781,10 +788,11 @@ static int sq_open(struct inode *inode, struct file *file)
                 sound_set_format(AFMT_MU_LAW);
         }
 #endif
-
+        unlock_kernel();
         return 0;
  out:
         module_put(dmasound.mach.owner);
+        unlock_kernel();
         return rc;
 }
 
@@ -1226,12 +1234,17 @@ static int state_open(struct inode *inode, struct file *file)
 {
         char *buffer = state.buf;
         int len = 0;
+        int ret;
 
+        lock_kernel();
+        ret = -EBUSY;
         if (state.busy)
-                return -EBUSY;
+                goto out;
 
+        ret = -ENODEV;
         if (!try_module_get(dmasound.mach.owner))
-                return -ENODEV;
+                goto out;
+
         state.ptr = 0;
         state.busy = 1;
 
@@ -1293,7 +1306,10 @@ printk("dmasound: stat buffer used %d bytes\n", len) ;
                 printk(KERN_ERR "dmasound_core: stat buffer overflowed!\n");
 
         state.len = len;
-        return 0;
+        ret = 0;
+out:
+        unlock_kernel();
+        return ret;
 }
 
 static int state_release(struct inode *inode, struct file *file)