From: Christoph Hellwig hch@lst.de
[ Upstream commit b3dc3f8e49577840dc8ac8a365c5b3da4edb10b8 ]
dma_alloc_coherent does not return a physical address, but a DMA address, which might be remapped or have an offset. Passing the DMA address to vm_iomap_memory is thus broken.
Use the proper dma_mmap_coherent helper instead, and stop passing __GFP_COMP to dma_alloc_coherent, as the memory management inside the DMA allocator is hidden from the callers and does not require it.
With this the gfp_t argument to __videobuf_dc_alloc can be removed and hard coded to GFP_KERNEL.
Fixes: a8f3c203e19b ("[media] videobuf-dma-contig: add cache support") Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/v4l2-core/videobuf-dma-contig.c | 22 +++++++------------ 1 file changed, 8 insertions(+), 14 deletions(-)
diff --git a/drivers/media/v4l2-core/videobuf-dma-contig.c b/drivers/media/v4l2-core/videobuf-dma-contig.c index aeb2f497c683..6a6cd046cefb 100644 --- a/drivers/media/v4l2-core/videobuf-dma-contig.c +++ b/drivers/media/v4l2-core/videobuf-dma-contig.c @@ -36,12 +36,11 @@ struct videobuf_dma_contig_memory {
static int __videobuf_dc_alloc(struct device *dev, struct videobuf_dma_contig_memory *mem, - unsigned long size, gfp_t flags) + unsigned long size) { mem->size = size; - mem->vaddr = dma_alloc_coherent(dev, mem->size, - &mem->dma_handle, flags); - + mem->vaddr = dma_alloc_coherent(dev, mem->size, &mem->dma_handle, + GFP_KERNEL); if (!mem->vaddr) { dev_err(dev, "memory alloc size %ld failed\n", mem->size); return -ENOMEM; @@ -258,8 +257,7 @@ static int __videobuf_iolock(struct videobuf_queue *q, return videobuf_dma_contig_user_get(mem, vb);
/* allocate memory for the read() method */ - if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size), - GFP_KERNEL)) + if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(vb->size))) return -ENOMEM; break; case V4L2_MEMORY_OVERLAY: @@ -295,22 +293,18 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q, BUG_ON(!mem); MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
- if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize), - GFP_KERNEL | __GFP_COMP)) + if (__videobuf_dc_alloc(q->dev, mem, PAGE_ALIGN(buf->bsize))) goto error;
- /* Try to remap memory */ - vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot); - /* the "vm_pgoff" is just used in v4l2 to find the * corresponding buffer data structure which is allocated * earlier and it does not mean the offset from the physical * buffer start address as usual. So set it to 0 to pass - * the sanity check in vm_iomap_memory(). + * the sanity check in dma_mmap_coherent(). */ vma->vm_pgoff = 0; - - retval = vm_iomap_memory(vma, mem->dma_handle, mem->size); + retval = dma_mmap_coherent(q->dev, vma, mem->vaddr, mem->dma_handle, + mem->size); if (retval) { dev_err(q->dev, "mmap: remap failed with error %d. ", retval);