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>

1 files changed, 33 insertions, 49 deletions

diff --git a/drivers/media/video/zoran/zoran_driver.c b/drivers/media/video/zoran/zoran_driver.c
index 21f37a68714b..120ef235e63d 100644
--- 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);*/