forked from Minki/linux
1faa39e0f3
As reported by smatch: drivers/media/v4l2-core/videobuf-dma-sg.c:245 videobuf_dma_init_kernel() warn: should 'nr_pages << 12' be a 64 bit type? The printk should not be using %d for the number of pages. After looking better, the real problem here is that the number of pages should be long int. Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
103 lines
2.8 KiB
C
103 lines
2.8 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
|
|
/*
|
|
* helper functions for SG DMA video4linux capture buffers
|
|
*
|
|
* The functions expect the hardware being able to scatter gather
|
|
* (i.e. the buffers are not linear in physical memory, but fragmented
|
|
* into PAGE_SIZE chunks). They also assume the driver does not need
|
|
* to touch the video data.
|
|
*
|
|
* (c) 2007 Mauro Carvalho Chehab, <mchehab@kernel.org>
|
|
*
|
|
* Highly based on video-buf written originally by:
|
|
* (c) 2001,02 Gerd Knorr <kraxel@bytesex.org>
|
|
* (c) 2006 Mauro Carvalho Chehab, <mchehab@kernel.org>
|
|
* (c) 2006 Ted Walther and John Sokol
|
|
*/
|
|
#ifndef _VIDEOBUF_DMA_SG_H
|
|
#define _VIDEOBUF_DMA_SG_H
|
|
|
|
#include <media/videobuf-core.h>
|
|
|
|
/* --------------------------------------------------------------------- */
|
|
|
|
/*
|
|
* A small set of helper functions to manage buffers (both userland
|
|
* and kernel) for DMA.
|
|
*
|
|
* videobuf_dma_init_*()
|
|
* creates a buffer. The userland version takes a userspace
|
|
* pointer + length. The kernel version just wants the size and
|
|
* does memory allocation too using vmalloc_32().
|
|
*
|
|
* videobuf_dma_*()
|
|
* see Documentation/core-api/dma-api-howto.rst, these functions to
|
|
* basically the same. The map function does also build a
|
|
* scatterlist for the buffer (and unmap frees it ...)
|
|
*
|
|
* videobuf_dma_free()
|
|
* no comment ...
|
|
*
|
|
*/
|
|
|
|
struct videobuf_dmabuf {
|
|
u32 magic;
|
|
|
|
/* for userland buffer */
|
|
int offset;
|
|
size_t size;
|
|
struct page **pages;
|
|
|
|
/* for kernel buffers */
|
|
void *vaddr;
|
|
struct page **vaddr_pages;
|
|
dma_addr_t *dma_addr;
|
|
struct device *dev;
|
|
|
|
/* for overlay buffers (pci-pci dma) */
|
|
dma_addr_t bus_addr;
|
|
|
|
/* common */
|
|
struct scatterlist *sglist;
|
|
int sglen;
|
|
unsigned long nr_pages;
|
|
int direction;
|
|
};
|
|
|
|
struct videobuf_dma_sg_memory {
|
|
u32 magic;
|
|
|
|
/* for mmap'ed buffers */
|
|
struct videobuf_dmabuf dma;
|
|
};
|
|
|
|
/*
|
|
* Scatter-gather DMA buffer API.
|
|
*
|
|
* These functions provide a simple way to create a page list and a
|
|
* scatter-gather list from a kernel, userspace of physical address and map the
|
|
* memory for DMA operation.
|
|
*
|
|
* Despite the name, this is totally unrelated to videobuf, except that
|
|
* videobuf-dma-sg uses the same API internally.
|
|
*/
|
|
int videobuf_dma_free(struct videobuf_dmabuf *dma);
|
|
|
|
int videobuf_dma_unmap(struct device *dev, struct videobuf_dmabuf *dma);
|
|
struct videobuf_dmabuf *videobuf_to_dma(struct videobuf_buffer *buf);
|
|
|
|
void *videobuf_sg_alloc(size_t size);
|
|
|
|
void videobuf_queue_sg_init(struct videobuf_queue *q,
|
|
const struct videobuf_queue_ops *ops,
|
|
struct device *dev,
|
|
spinlock_t *irqlock,
|
|
enum v4l2_buf_type type,
|
|
enum v4l2_field field,
|
|
unsigned int msize,
|
|
void *priv,
|
|
struct mutex *ext_lock);
|
|
|
|
#endif /* _VIDEOBUF_DMA_SG_H */
|
|
|