[PATCH 6/9] media: vb2: Convert vb2_vmalloc_get_userptr() to use frame vector

Jan Kara
2015-07-13T14:55:48Z

Convert vb2_vmalloc_get_userptr() to use frame vector infrastructure.
When we are doing that there's no need to allocate page array and some
code can be simplified.

Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Jan Kara <jack@suse.cz>
---
drivers/media/v4l2-core/videobuf2-vmalloc.c | 92 +++++++++++------------------
1 file changed, 36 insertions(+), 56 deletions(-)

diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index 63bef959623e..ecb8f0c7f025 100644
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -23,11 +23,9 @@

struct vb2_vmalloc_buf {
void *vaddr;
- struct page **pages;
- struct vm_area_struct *vma;
+ struct frame_vector *vec;
enum dma_data_direction dma_dir;
unsigned long size;
- unsigned int n_pages;
atomic_t refcount;
struct vb2_vmarea_handler handler;
struct dma_buf *dbuf;
@@ -76,10 +74,8 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
enum dma_data_direction dma_dir)
{
struct vb2_vmalloc_buf *buf;
- unsigned long first, last;
- int n_pages, offset;
- struct vm_area_struct *vma;
- dma_addr_t physp;
+ struct frame_vector *vec;
+ int n_pages, offset, i;

buf = kzalloc(sizeof(*buf), GFP_KERNEL);
if (!buf)
@@ -88,53 +84,36 @@ static void *vb2_vmalloc_get_userptr(void *alloc_ctx, unsigned long vaddr,
buf->dma_dir = dma_dir;
offset = vaddr & ~PAGE_MASK;
buf->size = size;
-
- down_read(&current->mm->mmap_sem);
- vma = find_vma(current->mm, vaddr);
- if (vma && (vma->vm_flags & VM_PFNMAP) && (vma->vm_pgoff)) {
- if (vb2_get_contig_userptr(vaddr, size, &vma, &physp))
- goto fail_pages_array_alloc;
- buf->vma = vma;
- buf->vaddr = (__force void *)ioremap_nocache(physp, size);
- if (!buf->vaddr)
- goto fail_pages_array_alloc;
+ vec = vb2_create_framevec(vaddr, size, dma_dir == DMA_FROM_DEVICE);
+ if (IS_ERR(vec))
+ goto fail_pfnvec_create;
+ buf->vec = vec;
+ n_pages = frame_vector_count(vec);
+ if (frame_vector_to_pages(vec) < 0) {
+ unsigned long *nums = frame_vector_pfns(vec);
+
+ /*
+ * We cannot get page pointers for these pfns. Check memory is
+ * physically contiguous and use direct mapping.
+ */
+ for (i = 1; i < n_pages; i++)
+ if (nums[i-1] + 1 != nums[i])
+ goto fail_map;
+ buf->vaddr = (__force void *)
+ ioremap_nocache(nums[0] << PAGE_SHIFT, size);
} else {
- first = vaddr >> PAGE_SHIFT;
- last = (vaddr + size - 1) >> PAGE_SHIFT;
- buf->n_pages = last - first + 1;
- buf->pages = kzalloc(buf->n_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto fail_pages_array_alloc;
-
- /* current->mm->mmap_sem is taken by videobuf2 core */
- n_pages = get_user_pages(current, current->mm,
- vaddr & PAGE_MASK, buf->n_pages,
- dma_dir == DMA_FROM_DEVICE,
- 1, /* force */
- buf->pages, NULL);
- if (n_pages != buf->n_pages)
- goto fail_get_user_pages;
-
- buf->vaddr = vm_map_ram(buf->pages, buf->n_pages, -1,
+ buf->vaddr = vm_map_ram(frame_vector_pages(vec), n_pages, -1,
PAGE_KERNEL);
- if (!buf->vaddr)
- goto fail_get_user_pages;
}
- up_read(&current->mm->mmap_sem);

+ if (!buf->vaddr)
+ goto fail_map;
buf->vaddr += offset;
return buf;

-fail_get_user_pages:
- pr_debug("get_user_pages requested/got: %d/%d]\n", n_pages,
- buf->n_pages);
- while (--n_pages >= 0)
- put_page(buf->pages[n_pages]);
- kfree(buf->pages);
-
-fail_pages_array_alloc:
- up_read(&current->mm->mmap_sem);
+fail_map:
+ vb2_destroy_framevec(vec);
+fail_pfnvec_create:
kfree(buf);

return NULL;
@@ -145,20 +124,21 @@ static void vb2_vmalloc_put_userptr(void *buf_priv)
struct vb2_vmalloc_buf *buf = buf_priv;
unsigned long vaddr = (unsigned long)buf->vaddr & PAGE_MASK;
unsigned int i;
+ struct page **pages;
+ unsigned int n_pages;

- if (buf->pages) {
+ if (!buf->vec->is_pfns) {
+ n_pages = frame_vector_count(buf->vec);
+ pages = frame_vector_pages(buf->vec);
if (vaddr)
- vm_unmap_ram((void *)vaddr, buf->n_pages);
- for (i = 0; i < buf->n_pages; ++i) {
- if (buf->dma_dir == DMA_FROM_DEVICE)
- set_page_dirty_lock(buf->pages[i]);
- put_page(buf->pages[i]);
- }
- kfree(buf->pages);
+ vm_unmap_ram((void *)vaddr, n_pages);
+ if (buf->dma_dir == DMA_FROM_DEVICE)
+ for (i = 0; i < n_pages; i++)
+ set_page_dirty_lock(pages[i]);
} else {
- vb2_put_vma(buf->vma);
iounmap((__force void __iomem *)buf->vaddr);
}
+ vb2_destroy_framevec(buf->vec);
kfree(buf);
}

--
2.1.4

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