From adfedd216d9f0bc3f5bfa8aab42932301d4edc31 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 11 Sep 2010 19:53:25 +0200 Subject: dvb/bt8xx: kill the big kernel lock The bt8xx driver only uses the big kernel lock in its dst_ca_ioctl function and never to serialize against other code, so we can trivially replace it with a private mutex. Signed-off-by: Arnd Bergmann Cc: linux-media@vger.kernel.org Cc: Mauro Carvalho Chehab --- drivers/media/dvb/bt8xx/dst_ca.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'drivers/media/dvb') diff --git a/drivers/media/dvb/bt8xx/dst_ca.c b/drivers/media/dvb/bt8xx/dst_ca.c index cf8705162845..d75788b4e22e 100644 --- a/drivers/media/dvb/bt8xx/dst_ca.c +++ b/drivers/media/dvb/bt8xx/dst_ca.c @@ -22,7 +22,7 @@ #include #include #include -#include +#include #include #include #include "dvbdev.h" @@ -52,6 +52,7 @@ } while(0) +static DEFINE_MUTEX(dst_ca_mutex); static unsigned int verbose = 5; module_param(verbose, int, 0644); MODULE_PARM_DESC(verbose, "verbose startup messages, default is 1 (yes)"); @@ -564,7 +565,7 @@ static long dst_ca_ioctl(struct file *file, unsigned int cmd, unsigned long ioct void __user *arg = (void __user *)ioctl_arg; int result = 0; - lock_kernel(); + mutex_lock(&dst_ca_mutex); dvbdev = file->private_data; state = (struct dst_state *)dvbdev->priv; p_ca_message = kmalloc(sizeof (struct ca_msg), GFP_KERNEL); @@ -652,7 +653,7 @@ static long dst_ca_ioctl(struct file *file, unsigned int cmd, unsigned long ioct kfree (p_ca_slot_info); kfree (p_ca_caps); - unlock_kernel(); + mutex_unlock(&dst_ca_mutex); return result; } -- cgit v1.2.3 From 72024f1ec5164a70d84dd8cf4458fe4064a6b692 Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Sat, 11 Sep 2010 19:56:45 +0200 Subject: dvb-core: kill the big kernel lock The dvb core only uses the big kernel lock in the open and ioctl functions, which means it can be replaced with a dvb specific mutex. Fortunately, all the ioctl functions go through dvb_usercopy, so we can move the serialization in there. Signed-off-by: Arnd Bergmann Cc: Mauro Carvalho Chehab Cc: linux-media@vger.kernel.org --- drivers/media/dvb/dvb-core/dmxdev.c | 17 ++--------------- drivers/media/dvb/dvb-core/dvb_ca_en50221.c | 8 +------- drivers/media/dvb/dvb-core/dvb_net.c | 9 +-------- drivers/media/dvb/dvb-core/dvbdev.c | 17 +++++++---------- 4 files changed, 11 insertions(+), 40 deletions(-) (limited to 'drivers/media/dvb') diff --git a/drivers/media/dvb/dvb-core/dmxdev.c b/drivers/media/dvb/dvb-core/dmxdev.c index 0042306ea11b..2de13b04b09d 100644 --- a/drivers/media/dvb/dvb-core/dmxdev.c +++ b/drivers/media/dvb/dvb-core/dmxdev.c @@ -25,7 +25,6 @@ #include #include #include -#include #include #include #include @@ -1088,13 +1087,7 @@ static int dvb_demux_do_ioctl(struct file *file, static long dvb_demux_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - int ret; - - lock_kernel(); - ret = dvb_usercopy(file, cmd, arg, dvb_demux_do_ioctl); - unlock_kernel(); - - return ret; + return dvb_usercopy(file, cmd, arg, dvb_demux_do_ioctl); } static unsigned int dvb_demux_poll(struct file *file, poll_table *wait) @@ -1186,13 +1179,7 @@ static int dvb_dvr_do_ioctl(struct file *file, static long dvb_dvr_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - int ret; - - lock_kernel(); - ret = dvb_usercopy(file, cmd, arg, dvb_dvr_do_ioctl); - unlock_kernel(); - - return ret; + return dvb_usercopy(file, cmd, arg, dvb_dvr_do_ioctl); } static unsigned int dvb_dvr_poll(struct file *file, poll_table *wait) diff --git a/drivers/media/dvb/dvb-core/dvb_ca_en50221.c b/drivers/media/dvb/dvb-core/dvb_ca_en50221.c index cb97e6b85432..1723a984a522 100644 --- a/drivers/media/dvb/dvb-core/dvb_ca_en50221.c +++ b/drivers/media/dvb/dvb-core/dvb_ca_en50221.c @@ -1259,13 +1259,7 @@ static int dvb_ca_en50221_io_do_ioctl(struct file *file, static long dvb_ca_en50221_io_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - int ret; - - lock_kernel(); - ret = dvb_usercopy(file, cmd, arg, dvb_ca_en50221_io_do_ioctl); - unlock_kernel(); - - return ret; + return dvb_usercopy(file, cmd, arg, dvb_ca_en50221_io_do_ioctl); } diff --git a/drivers/media/dvb/dvb-core/dvb_net.c b/drivers/media/dvb/dvb-core/dvb_net.c index 6c3a8a06ccab..a08032284cbf 100644 --- a/drivers/media/dvb/dvb-core/dvb_net.c +++ b/drivers/media/dvb/dvb-core/dvb_net.c @@ -59,7 +59,6 @@ #include #include #include -#include #include #include #include @@ -1445,13 +1444,7 @@ static int dvb_net_do_ioctl(struct file *file, static long dvb_net_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { - int ret; - - lock_kernel(); - ret = dvb_usercopy(file, cmd, arg, dvb_net_do_ioctl); - unlock_kernel(); - - return ret; + return dvb_usercopy(file, cmd, arg, dvb_net_do_ioctl); } static int dvb_net_close(struct inode *inode, struct file *file) diff --git a/drivers/media/dvb/dvb-core/dvbdev.c b/drivers/media/dvb/dvb-core/dvbdev.c index b915c39d782f..28f486edcaf0 100644 --- a/drivers/media/dvb/dvb-core/dvbdev.c +++ b/drivers/media/dvb/dvb-core/dvbdev.c @@ -32,9 +32,9 @@ #include #include #include -#include #include "dvbdev.h" +static DEFINE_MUTEX(dvbdev_mutex); static int dvbdev_debug; module_param(dvbdev_debug, int, 0644); @@ -68,7 +68,7 @@ static int dvb_device_open(struct inode *inode, struct file *file) { struct dvb_device *dvbdev; - lock_kernel(); + mutex_lock(&dvbdev_mutex); down_read(&minor_rwsem); dvbdev = dvb_minors[iminor(inode)]; @@ -91,12 +91,12 @@ static int dvb_device_open(struct inode *inode, struct file *file) } fops_put(old_fops); up_read(&minor_rwsem); - unlock_kernel(); + mutex_unlock(&dvbdev_mutex); return err; } fail: up_read(&minor_rwsem); - unlock_kernel(); + mutex_unlock(&dvbdev_mutex); return -ENODEV; } @@ -158,7 +158,6 @@ long dvb_generic_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { struct dvb_device *dvbdev = file->private_data; - int ret; if (!dvbdev) return -ENODEV; @@ -166,11 +165,7 @@ long dvb_generic_ioctl(struct file *file, if (!dvbdev->kernel_ioctl) return -EINVAL; - lock_kernel(); - ret = dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl); - unlock_kernel(); - - return ret; + return dvb_usercopy(file, cmd, arg, dvbdev->kernel_ioctl); } EXPORT_SYMBOL(dvb_generic_ioctl); @@ -421,8 +416,10 @@ int dvb_usercopy(struct file *file, } /* call driver */ + mutex_lock(&dvbdev_mutex); if ((err = func(file, cmd, parg)) == -ENOIOCTLCMD) err = -EINVAL; + mutex_unlock(&dvbdev_mutex); if (err < 0) goto out; -- cgit v1.2.3