Commit a17ae147 authored May 13, 2019 by Souptick Joarder Committed by Linus Torvalds May 14, 2019

videobuf2/videobuf2-dma-sg.c: convert to use vm_map_pages()

Convert to use vm_map_pages() to map range of kernel memory to user vma.

vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer, not as a
in-buffer offset by design and it always want to mmap a whole buffer from
its beginning.

Link: http://lkml.kernel.org/r/a953fe6b3056de1cc6eab654effdd4a22f125375.1552921225.git.jrdr.linux@gmail.com


Signed-off-by: Souptick Joarder <jrdr.linux@gmail.com>
Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Heiko Stuebner <heiko@sntech.de>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Juergen Gross <jgross@suse.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
Cc: Pawel Osciak <pawel@osciak.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sandy Huang <hjc@rock-chips.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent b0d0084f

drivers/media/common/videobuf2/videobuf2-core.c

+7 −0

Original line number	Diff line number	Diff line
		@@ -2201,6 +2201,13 @@ int vb2_mmap(struct vb2_queue q, struct vm_area_struct vma)
		goto unlock;
		}

		/*
		* vm_pgoff is treated in V4L2 API as a 'cookie' to select a buffer,
		* not as a in-buffer offset. We always want to mmap a whole buffer
		* from its beginning.
		*/
		vma->vm_pgoff = 0;

		ret = call_memop(vb, mmap, vb->planes[plane].mem_priv, vma);

		unlock:

drivers/media/common/videobuf2/videobuf2-dma-contig.c

+0 −6

Original line number	Diff line number	Diff line
		@@ -186,12 +186,6 @@ static int vb2_dc_mmap(void buf_priv, struct vm_area_struct vma)
		return -EINVAL;
		}

		/*
		* dma_mmap_* uses vm_pgoff as in-buffer offset, but we want to
		* map whole buffer
		*/
		vma->vm_pgoff = 0;

		ret = dma_mmap_attrs(buf->dev, vma, buf->cookie,
		buf->dma_addr, buf->size, buf->attrs);

drivers/media/common/videobuf2/videobuf2-dma-sg.c

+6 −16

Original line number	Diff line number	Diff line
		@@ -328,29 +328,19 @@ static unsigned int vb2_dma_sg_num_users(void *buf_priv)
		static int vb2_dma_sg_mmap(void buf_priv, struct vm_area_struct vma)
		{
		struct vb2_dma_sg_buf *buf = buf_priv;
		unsigned long uaddr = vma->vm_start;
		unsigned long usize = vma->vm_end - vma->vm_start;
		int i = 0;
		int err;

		if (!buf) {
		printk(KERN_ERR "No memory to map\n");
		return -EINVAL;
		}

		do {
		int ret;

		ret = vm_insert_page(vma, uaddr, buf->pages[i++]);
		if (ret) {
		printk(KERN_ERR "Remapping memory, error: %d\n", ret);
		return ret;
		err = vm_map_pages(vma, buf->pages, buf->num_pages);
		if (err) {
		printk(KERN_ERR "Remapping memory, error: %d\n", err);
		return err;
		}

		uaddr += PAGE_SIZE;
		usize -= PAGE_SIZE;
		} while (usize > 0);


		/*
		* Use common vm_area operations to track buffer refcount.
		*/