[media] staging/cx25721: serialize access to devlist

Out of the three files accessing the device list,
one uses a mutex, one uses the BKL and one does
not have any locking. That is of course pointless,
so let's make all of them use the same mutex,
and get rid of one more BKL user.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Palash Bandyopadhyay <palash.bandyopadhyay@conexant.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/staging/cx25821/Kconfig b/drivers/staging/cx25821/Kconfig
index b2656957aa8f1fc7747486804df0b8c3fdafe1b8..5f6b5421371356043cf7768989e5417d6da8e572 100644 (file)
--- a/drivers/staging/cx25821/Kconfig
+++ b/drivers/staging/cx25821/Kconfig
@@ -1,7 +1,6 @@
 config VIDEO_CX25821
        tristate "Conexant cx25821 support"
        depends on DVB_CORE && VIDEO_DEV && PCI && I2C
-       depends on BKL # please fix
        select I2C_ALGOBIT
        select VIDEO_BTCX
        select VIDEO_TVEEPROM

diff --git a/drivers/staging/cx25821/cx25821-alsa.c b/drivers/staging/cx25821/cx25821-alsa.c
index 160f6693aa333b53e84dfdbd58f827451dd2bbd2..ebdba7c65bc5f467c39ad8c385ab276b23dc177d 100644 (file)
--- a/drivers/staging/cx25821/cx25821-alsa.c
+++ b/drivers/staging/cx25821/cx25821-alsa.c
@@ -770,10 +770,12 @@ static int cx25821_alsa_init(void)
        struct cx25821_dev *dev = NULL;
        struct list_head *list;
 
+       mutex_lock(&cx25821_devlist_mutex);
        list_for_each(list, &cx25821_devlist) {
                dev = list_entry(list, struct cx25821_dev, devlist);
                cx25821_audio_initdev(dev);
        }
+       mutex_unlock(&cx25821_devlist_mutex);
 
        if (dev == NULL)
                pr_info("ERROR ALSA: no cx25821 cards found\n");

diff --git a/drivers/staging/cx25821/cx25821-core.c b/drivers/staging/cx25821/cx25821-core.c
index a216b620b718eb12ded396b5391e1f43894e121f..523ac5e16c1b2d05d5a68fefc8a9fea5967d3eff 100644 (file)
--- a/drivers/staging/cx25821/cx25821-core.c
+++ b/drivers/staging/cx25821/cx25821-core.c
@@ -33,9 +33,6 @@ MODULE_DESCRIPTION("Driver for Athena cards");
 MODULE_AUTHOR("Shu Lin - Hiep Huynh");
 MODULE_LICENSE("GPL");
 
-struct list_head cx25821_devlist;
-EXPORT_SYMBOL(cx25821_devlist);
-
 static unsigned int debug;
 module_param(debug, int, 0644);
 MODULE_PARM_DESC(debug, "enable debug messages");
@@ -46,8 +43,10 @@ MODULE_PARM_DESC(card, "card type");
 
 static unsigned int cx25821_devcount;
 
-static DEFINE_MUTEX(devlist);
+DEFINE_MUTEX(cx25821_devlist_mutex);
+EXPORT_SYMBOL(cx25821_devlist_mutex);
 LIST_HEAD(cx25821_devlist);
+EXPORT_SYMBOL(cx25821_devlist);
 
 struct sram_channel cx25821_sram_channels[] = {
        [SRAM_CH00] = {
@@ -911,9 +910,9 @@ static int cx25821_dev_setup(struct cx25821_dev *dev)
        dev->nr = ++cx25821_devcount;
        sprintf(dev->name, "cx25821[%d]", dev->nr);
 
-       mutex_lock(&devlist);
+       mutex_lock(&cx25821_devlist_mutex);
        list_add_tail(&dev->devlist, &cx25821_devlist);
-       mutex_unlock(&devlist);
+       mutex_unlock(&cx25821_devlist_mutex);
 
        strcpy(cx25821_boards[UNKNOWN_BOARD].name, "unknown");
        strcpy(cx25821_boards[CX25821_BOARD].name, "cx25821");
@@ -1465,9 +1464,9 @@ static void __devexit cx25821_finidev(struct pci_dev *pci_dev)
        if (pci_dev->irq)
                free_irq(pci_dev->irq, dev);
 
-       mutex_lock(&devlist);
+       mutex_lock(&cx25821_devlist_mutex);
        list_del(&dev->devlist);
-       mutex_unlock(&devlist);
+       mutex_unlock(&cx25821_devlist_mutex);
 
        cx25821_dev_unregister(dev);
        v4l2_device_unregister(v4l2_dev);
@@ -1501,7 +1500,6 @@ static struct pci_driver cx25821_pci_driver = {
 
 static int __init cx25821_init(void)
 {
-       INIT_LIST_HEAD(&cx25821_devlist);
        pr_info("driver version %d.%d.%d loaded\n",
                (CX25821_VERSION_CODE >> 16) & 0xff,
                (CX25821_VERSION_CODE >> 8) & 0xff,

diff --git a/drivers/staging/cx25821/cx25821-video.c b/drivers/staging/cx25821/cx25821-video.c
index 0d8d75670516e77a8cc1b9218c87c5f8821c9778..ab05392386e86e2f19b9214c94d57532759bcca7 100644 (file)
--- a/drivers/staging/cx25821/cx25821-video.c
+++ b/drivers/staging/cx25821/cx25821-video.c
@@ -27,7 +27,6 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
 #include "cx25821-video.h"
-#include <linux/smp_lock.h>
 
 MODULE_DESCRIPTION("v4l2 driver module for cx25821 based TV cards");
 MODULE_AUTHOR("Hiep Huynh <hiep.huynh@conexant.com>");
@@ -815,7 +814,7 @@ static int video_open(struct file *file)
        if (NULL == fh)
               return -ENOMEM;
 
-       lock_kernel();
+       mutex_lock(&cx25821_devlist_mutex);
 
        list_for_each(list, &cx25821_devlist)
        {
@@ -832,8 +831,8 @@ static int video_open(struct file *file)
        }
 
        if (NULL == dev) {
-              unlock_kernel();
-              return -ENODEV;
+               mutex_unlock(&cx25821_devlist_mutex);
+               return -ENODEV;
        }
 
        file->private_data = fh;
@@ -862,7 +861,7 @@ static int video_open(struct file *file)
                              sizeof(struct cx25821_buffer), fh, NULL);
 
        dprintk(1, "post videobuf_queue_init()\n");
-       unlock_kernel();
+       mutex_unlock(&cx25821_devlist_mutex);
 
        return 0;
 }

diff --git a/drivers/staging/cx25821/cx25821.h b/drivers/staging/cx25821/cx25821.h
index 55115235f7f66e2acb5b52d0fc8d308575b8c972..6230243e2ccbcfa3b63d11f4e1165490a9f940b0 100644 (file)
--- a/drivers/staging/cx25821/cx25821.h
+++ b/drivers/staging/cx25821/cx25821.h
@@ -31,7 +31,6 @@
 #include <linux/delay.h>
 #include <linux/sched.h>
 #include <linux/kdev_t.h>
-#include <linux/smp_lock.h>
 
 #include <media/v4l2-common.h>
 #include <media/v4l2-device.h>
@@ -445,6 +444,8 @@ static inline struct cx25821_dev *get_cx25821(struct v4l2_device *v4l2_dev)
        v4l2_device_call_all(&dev->v4l2_dev, 0, o, f, ##args)
 
 extern struct list_head cx25821_devlist;
+extern struct mutex cx25821_devlist_mutex;
+
 extern struct cx25821_board cx25821_boards[];
 extern struct cx25821_subid cx25821_subids[];