V4L/DVB (10226): zoran: Get rid of extra module ref count

The zoran driver does a module_get/put of THIS_MODULE on device open/close.
This isn't necessary as the kernel does this automatically.

Clean up the failure path of zoran_open() somewhat.

Make the dprintk()s on open/close a higher debug level and make the user
count printed take the current open/close into account.

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/zoran/zoran_driver.c b/drivers/media/video/zoran/zoran_driver.c
index 21f37a68714b32b37deead9bd026e03c1ca326ed..120ef235e63d07a3d8a3a9c16ae03006bcbdc4cf 100644 (file)
--- a/drivers/media/video/zoran/zoran_driver.c
+++ b/drivers/media/video/zoran/zoran_driver.c
@@ -1200,7 +1200,10 @@ static int zoran_open(struct file *file)
 {
        struct zoran *zr = video_drvdata(file);
        struct zoran_fh *fh;
-       int res, first_open = 0, have_module_locks = 0;
+       int res, first_open = 0;
+
+       dprintk(2, KERN_INFO "%s: zoran_open(%s, pid=[%d]), users(-)=%d\n",
+               ZR_DEVNAME(zr), current->comm, task_pid_nr(current), zr->user + 1);
 
        lock_kernel();
 
@@ -1208,56 +1211,39 @@ static int zoran_open(struct file *file)
         * so locking ourselves only causes deadlocks */
        /*mutex_lock(&zr->resource_lock);*/
 
+       if (zr->user >= 2048) {
+               dprintk(1, KERN_ERR "%s: too many users (%d) on device\n",
+                       ZR_DEVNAME(zr), zr->user);
+               res = -EBUSY;
+               goto fail_unlock;
+       }
+
        if (!zr->decoder) {
                dprintk(1,
                        KERN_ERR "%s: no TV decoder loaded for device!\n",
                        ZR_DEVNAME(zr));
                res = -EIO;
-               goto open_unlock_and_return;
+               goto fail_unlock;
        }
 
-       /* try to grab a module lock */
-       if (!try_module_get(THIS_MODULE)) {
-               dprintk(1,
-                       KERN_ERR
-                       "%s: failed to acquire my own lock! PANIC!\n",
-                       ZR_DEVNAME(zr));
-               res = -ENODEV;
-               goto open_unlock_and_return;
-       }
        if (!try_module_get(zr->decoder->driver->driver.owner)) {
                dprintk(1,
                        KERN_ERR
-                       "%s: failed to grab ownership of i2c decoder\n",
+                       "%s: failed to grab ownership of video decoder\n",
                        ZR_DEVNAME(zr));
                res = -EIO;
-               module_put(THIS_MODULE);
-               goto open_unlock_and_return;
+               goto fail_unlock;
        }
        if (zr->encoder &&
            !try_module_get(zr->encoder->driver->driver.owner)) {
                dprintk(1,
                        KERN_ERR
-                       "%s: failed to grab ownership of i2c encoder\n",
+                       "%s: failed to grab ownership of video encoder\n",
                        ZR_DEVNAME(zr));
                res = -EIO;
-               module_put(zr->decoder->driver->driver.owner);
-               module_put(THIS_MODULE);
-               goto open_unlock_and_return;
-       }
-
-       have_module_locks = 1;
-
-       if (zr->user >= 2048) {
-               dprintk(1, KERN_ERR "%s: too many users (%d) on device\n",
-                       ZR_DEVNAME(zr), zr->user);
-               res = -EBUSY;
-               goto open_unlock_and_return;
+               goto fail_decoder;
        }
 
-       dprintk(1, KERN_INFO "%s: zoran_open(%s, pid=[%d]), users(-)=%d\n",
-               ZR_DEVNAME(zr), current->comm, task_pid_nr(current), zr->user);
-
        /* now, create the open()-specific file_ops struct */
        fh = kzalloc(sizeof(struct zoran_fh), GFP_KERNEL);
        if (!fh) {
@@ -1266,7 +1252,7 @@ static int zoran_open(struct file *file)
                        "%s: zoran_open() - allocation of zoran_fh failed\n",
                        ZR_DEVNAME(zr));
                res = -ENOMEM;
-               goto open_unlock_and_return;
+               goto fail_encoder;
        }
        /* used to be BUZ_MAX_WIDTH/HEIGHT, but that gives overflows
         * on norm-change! */
@@ -1277,9 +1263,8 @@ static int zoran_open(struct file *file)
                        KERN_ERR
                        "%s: zoran_open() - allocation of overlay_mask failed\n",
                        ZR_DEVNAME(zr));
-               kfree(fh);
                res = -ENOMEM;
-               goto open_unlock_and_return;
+               goto fail_fh;
        }
 
        if (zr->user++ == 0)
@@ -1304,18 +1289,19 @@ static int zoran_open(struct file *file)
 
        return 0;
 
-open_unlock_and_return:
-       /* if we grabbed locks, release them accordingly */
-       if (have_module_locks) {
-               module_put(zr->decoder->driver->driver.owner);
-               if (zr->encoder) {
-                       module_put(zr->encoder->driver->driver.owner);
-               }
-               module_put(THIS_MODULE);
-       }
-
+fail_fh:
+       kfree(fh);
+fail_encoder:
+       if (zr->encoder)
+               module_put(zr->encoder->driver->driver.owner);
+fail_decoder:
+       module_put(zr->decoder->driver->driver.owner);
+fail_unlock:
        unlock_kernel();
 
+       dprintk(2, KERN_INFO "%s: open failed (%d), users(-)=%d\n",
+               ZR_DEVNAME(zr), res, zr->user);
+
        return res;
 }
 
@@ -1325,8 +1311,8 @@ zoran_close(struct file  *file)
        struct zoran_fh *fh = file->private_data;
        struct zoran *zr = fh->zr;
 
-       dprintk(1, KERN_INFO "%s: zoran_close(%s, pid=[%d]), users(+)=%d\n",
-               ZR_DEVNAME(zr), current->comm, task_pid_nr(current), zr->user);
+       dprintk(2, KERN_INFO "%s: zoran_close(%s, pid=[%d]), users(+)=%d\n",
+               ZR_DEVNAME(zr), current->comm, task_pid_nr(current), zr->user - 1);
 
        /* kernel locks (fs/device.c), so don't do that ourselves
         * (prevents deadlocks) */
@@ -1372,10 +1358,8 @@ zoran_close(struct file  *file)
 
        /* release locks on the i2c modules */
        module_put(zr->decoder->driver->driver.owner);
-       if (zr->encoder) {
-                module_put(zr->encoder->driver->driver.owner);
-       }
-       module_put(THIS_MODULE);
+       if (zr->encoder)
+               module_put(zr->encoder->driver->driver.owner);
 
        /*mutex_unlock(&zr->resource_lock);*/