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author | Ingo Molnar <mingo@elte.hu> | 2011-01-05 14:14:42 +0100 |
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committer | Ingo Molnar <mingo@elte.hu> | 2011-01-05 14:14:46 +0100 |
commit | 27066fd484a32c80630136aa2b91c980f3198f9d (patch) | |
tree | 78ddabdedbfd7525d13ecd62a745525843f1d0e8 /drivers/media/video/uvc/uvc_queue.c | |
parent | 101e5f77bf35679809586e250b6c62193d2ed179 (diff) | |
parent | 3c0eee3fe6a3a1c745379547c7e7c904aa64f6d5 (diff) | |
download | kernel_samsung_aries-27066fd484a32c80630136aa2b91c980f3198f9d.zip kernel_samsung_aries-27066fd484a32c80630136aa2b91c980f3198f9d.tar.gz kernel_samsung_aries-27066fd484a32c80630136aa2b91c980f3198f9d.tar.bz2 |
Merge commit 'v2.6.37' into sched/core
Merge reason: Merge the final .37 tree.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'drivers/media/video/uvc/uvc_queue.c')
-rw-r--r-- | drivers/media/video/uvc/uvc_queue.c | 133 |
1 files changed, 110 insertions, 23 deletions
diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c index ed6d544..f14581b 100644 --- a/drivers/media/video/uvc/uvc_queue.c +++ b/drivers/media/video/uvc/uvc_queue.c @@ -90,6 +90,39 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type, } /* + * Free the video buffers. + * + * This function must be called with the queue lock held. + */ +static int __uvc_free_buffers(struct uvc_video_queue *queue) +{ + unsigned int i; + + for (i = 0; i < queue->count; ++i) { + if (queue->buffer[i].vma_use_count != 0) + return -EBUSY; + } + + if (queue->count) { + vfree(queue->mem); + queue->count = 0; + } + + return 0; +} + +int uvc_free_buffers(struct uvc_video_queue *queue) +{ + int ret; + + mutex_lock(&queue->mutex); + ret = __uvc_free_buffers(queue); + mutex_unlock(&queue->mutex); + + return ret; +} + +/* * Allocate the video buffers. * * Pages are reserved to make sure they will not be swapped, as they will be @@ -110,7 +143,7 @@ int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers, mutex_lock(&queue->mutex); - if ((ret = uvc_free_buffers(queue)) < 0) + if ((ret = __uvc_free_buffers(queue)) < 0) goto done; /* Bail out if no buffers should be allocated. */ @@ -152,28 +185,6 @@ done: } /* - * Free the video buffers. - * - * This function must be called with the queue lock held. - */ -int uvc_free_buffers(struct uvc_video_queue *queue) -{ - unsigned int i; - - for (i = 0; i < queue->count; ++i) { - if (queue->buffer[i].vma_use_count != 0) - return -EBUSY; - } - - if (queue->count) { - vfree(queue->mem); - queue->count = 0; - } - - return 0; -} - -/* * Check if buffers have been allocated. */ int uvc_queue_allocated(struct uvc_video_queue *queue) @@ -369,6 +380,82 @@ done: } /* + * VMA operations. + */ +static void uvc_vm_open(struct vm_area_struct *vma) +{ + struct uvc_buffer *buffer = vma->vm_private_data; + buffer->vma_use_count++; +} + +static void uvc_vm_close(struct vm_area_struct *vma) +{ + struct uvc_buffer *buffer = vma->vm_private_data; + buffer->vma_use_count--; +} + +static const struct vm_operations_struct uvc_vm_ops = { + .open = uvc_vm_open, + .close = uvc_vm_close, +}; + +/* + * Memory-map a video buffer. + * + * This function implements video buffers memory mapping and is intended to be + * used by the device mmap handler. + */ +int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma) +{ + struct uvc_buffer *uninitialized_var(buffer); + struct page *page; + unsigned long addr, start, size; + unsigned int i; + int ret = 0; + + start = vma->vm_start; + size = vma->vm_end - vma->vm_start; + + mutex_lock(&queue->mutex); + + for (i = 0; i < queue->count; ++i) { + buffer = &queue->buffer[i]; + if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff) + break; + } + + if (i == queue->count || size != queue->buf_size) { + ret = -EINVAL; + goto done; + } + + /* + * VM_IO marks the area as being an mmaped region for I/O to a + * device. It also prevents the region from being core dumped. + */ + vma->vm_flags |= VM_IO; + + addr = (unsigned long)queue->mem + buffer->buf.m.offset; + while (size > 0) { + page = vmalloc_to_page((void *)addr); + if ((ret = vm_insert_page(vma, start, page)) < 0) + goto done; + + start += PAGE_SIZE; + addr += PAGE_SIZE; + size -= PAGE_SIZE; + } + + vma->vm_ops = &uvc_vm_ops; + vma->vm_private_data = buffer; + uvc_vm_open(vma); + +done: + mutex_unlock(&queue->mutex); + return ret; +} + +/* * Poll the video queue. * * This function implements video queue polling and is intended to be used by |