From 438bd525e5240a48233cd3290f7fe66ff0167e20 Mon Sep 17 00:00:00 2001 From: Stefan Richter Date: Mon, 3 Jul 2006 12:02:32 -0400 Subject: [PATCH] [PATCH] ieee1394: dv1394: sem2mutex conversion Signed-off-by: Stefan Richter (not runtime-tested) Signed-off-by: Ben Collins --- drivers/ieee1394/dv1394-private.h | 6 +++--- drivers/ieee1394/dv1394.c | 31 ++++++++++++++++--------------- 2 files changed, 19 insertions(+), 18 deletions(-) diff --git a/drivers/ieee1394/dv1394-private.h b/drivers/ieee1394/dv1394-private.h index 80b5ac7fe38..7d1d2845b42 100644 --- a/drivers/ieee1394/dv1394-private.h +++ b/drivers/ieee1394/dv1394-private.h @@ -460,7 +460,7 @@ struct video_card { int dma_running; /* - 3) the sleeping semaphore 'sem' - this is used from process context only, + 3) the sleeping mutex 'mtx' - this is used from process context only, to serialize various operations on the video_card. Even though only one open() is allowed, we still need to prevent multiple threads of execution from entering calls like read, write, ioctl, etc. @@ -468,9 +468,9 @@ struct video_card { I honestly can't think of a good reason to use dv1394 from several threads at once, but we need to serialize anyway to prevent oopses =). - NOTE: if you need both spinlock and sem, take sem first to avoid deadlock! + NOTE: if you need both spinlock and mtx, take mtx first to avoid deadlock! */ - struct semaphore sem; + struct mutex mtx; /* people waiting for buffer space, please form a line here... */ wait_queue_head_t waitq; diff --git a/drivers/ieee1394/dv1394.c b/drivers/ieee1394/dv1394.c index bdc50f25fb4..6e71d68b109 100644 --- a/drivers/ieee1394/dv1394.c +++ b/drivers/ieee1394/dv1394.c @@ -95,6 +95,7 @@ #include #include #include +#include #include #include #include @@ -247,7 +248,7 @@ static void frame_delete(struct frame *f) Frame_prepare() must be called OUTSIDE the video->spinlock. However, frame_prepare() must still be serialized, so - it should be called WITH the video->sem taken. + it should be called WITH the video->mtx taken. */ static void frame_prepare(struct video_card *video, unsigned int this_frame) @@ -1271,7 +1272,7 @@ static int dv1394_mmap(struct file *file, struct vm_area_struct *vma) int retval = -EINVAL; /* serialize mmap */ - down(&video->sem); + mutex_lock(&video->mtx); if ( ! video_card_initialized(video) ) { retval = do_dv1394_init_default(video); @@ -1281,7 +1282,7 @@ static int dv1394_mmap(struct file *file, struct vm_area_struct *vma) retval = dma_region_mmap(&video->dv_buf, file, vma); out: - up(&video->sem); + mutex_unlock(&video->mtx); return retval; } @@ -1337,17 +1338,17 @@ static ssize_t dv1394_write(struct file *file, const char __user *buffer, size_t /* serialize this to prevent multi-threaded mayhem */ if (file->f_flags & O_NONBLOCK) { - if (down_trylock(&video->sem)) + if (!mutex_trylock(&video->mtx)) return -EAGAIN; } else { - if (down_interruptible(&video->sem)) + if (mutex_lock_interruptible(&video->mtx)) return -ERESTARTSYS; } if ( !video_card_initialized(video) ) { ret = do_dv1394_init_default(video); if (ret) { - up(&video->sem); + mutex_unlock(&video->mtx); return ret; } } @@ -1418,7 +1419,7 @@ static ssize_t dv1394_write(struct file *file, const char __user *buffer, size_t remove_wait_queue(&video->waitq, &wait); set_current_state(TASK_RUNNING); - up(&video->sem); + mutex_unlock(&video->mtx); return ret; } @@ -1434,17 +1435,17 @@ static ssize_t dv1394_read(struct file *file, char __user *buffer, size_t count /* serialize this to prevent multi-threaded mayhem */ if (file->f_flags & O_NONBLOCK) { - if (down_trylock(&video->sem)) + if (!mutex_trylock(&video->mtx)) return -EAGAIN; } else { - if (down_interruptible(&video->sem)) + if (mutex_lock_interruptible(&video->mtx)) return -ERESTARTSYS; } if ( !video_card_initialized(video) ) { ret = do_dv1394_init_default(video); if (ret) { - up(&video->sem); + mutex_unlock(&video->mtx); return ret; } video->continuity_counter = -1; @@ -1526,7 +1527,7 @@ static ssize_t dv1394_read(struct file *file, char __user *buffer, size_t count remove_wait_queue(&video->waitq, &wait); set_current_state(TASK_RUNNING); - up(&video->sem); + mutex_unlock(&video->mtx); return ret; } @@ -1547,12 +1548,12 @@ static long dv1394_ioctl(struct file *file, unsigned int cmd, unsigned long arg) /* serialize this to prevent multi-threaded mayhem */ if (file->f_flags & O_NONBLOCK) { - if (down_trylock(&video->sem)) { + if (!mutex_trylock(&video->mtx)) { unlock_kernel(); return -EAGAIN; } } else { - if (down_interruptible(&video->sem)) { + if (mutex_lock_interruptible(&video->mtx)) { unlock_kernel(); return -ERESTARTSYS; } @@ -1778,7 +1779,7 @@ static long dv1394_ioctl(struct file *file, unsigned int cmd, unsigned long arg) } out: - up(&video->sem); + mutex_unlock(&video->mtx); unlock_kernel(); return ret; } @@ -2253,7 +2254,7 @@ static int dv1394_init(struct ti_ohci *ohci, enum pal_or_ntsc format, enum modes clear_bit(0, &video->open); spin_lock_init(&video->spinlock); video->dma_running = 0; - init_MUTEX(&video->sem); + mutex_init(&video->mtx); init_waitqueue_head(&video->waitq); video->fasync = NULL; -- 2.41.1