[PATCH 5/9] media: vb2: Convert vb2_dma_sg_get_userptr() to use frame vector

Jan Kara
2015-07-13T14:56:01Z

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-dma-sg.c | 95 +++++-------------------------
1 file changed, 15 insertions(+), 80 deletions(-)

diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index d2cf113d1933..be7bd6535c9d 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -38,6 +38,7 @@ struct vb2_dma_sg_buf {
struct device *dev;
void *vaddr;
struct page **pages;
+ struct frame_vector *vec;
int offset;
enum dma_data_direction dma_dir;
struct sg_table sg_table;
@@ -51,7 +52,6 @@ struct vb2_dma_sg_buf {
unsigned int num_pages;
atomic_t refcount;
struct vb2_vmarea_handler handler;
- struct vm_area_struct *vma;

struct dma_buf_attachment *db_attach;
};
@@ -225,25 +225,17 @@ static void vb2_dma_sg_finish(void *buf_priv)
dma_sync_sg_for_cpu(buf->dev, sgt->sgl, sgt->nents, buf->dma_dir);
}

-static inline int vma_is_io(struct vm_area_struct *vma)
-{
- return !!(vma->vm_flags & (VM_IO | VM_PFNMAP));
-}
-
static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
unsigned long size,
enum dma_data_direction dma_dir)
{
struct vb2_dma_sg_conf *conf = alloc_ctx;
struct vb2_dma_sg_buf *buf;
- unsigned long first, last;
- int num_pages_from_user;
- struct vm_area_struct *vma;
struct sg_table *sgt;
DEFINE_DMA_ATTRS(attrs);
+ struct frame_vector *vec;

dma_set_attr(DMA_ATTR_SKIP_CPU_SYNC, &attrs);
-
buf = kzalloc(sizeof *buf, GFP_KERNEL);
if (!buf)
return NULL;
@@ -254,63 +246,19 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,
buf->offset = vaddr & ~PAGE_MASK;
buf->size = size;
buf->dma_sgt = &buf->sg_table;
+ vec = vb2_create_framevec(vaddr, size, buf->dma_dir == DMA_FROM_DEVICE);
+ if (IS_ERR(vec))
+ goto userptr_fail_pfnvec;
+ buf->vec = vec;

- first = (vaddr & PAGE_MASK) >> PAGE_SHIFT;
- last = ((vaddr + size - 1) & PAGE_MASK) >> PAGE_SHIFT;
- buf->num_pages = last - first + 1;
-
- buf->pages = kzalloc(buf->num_pages * sizeof(struct page *),
- GFP_KERNEL);
- if (!buf->pages)
- goto userptr_fail_alloc_pages;
-
- down_read(&current->mm->mmap_sem);
- vma = find_vma(current->mm, vaddr);
- if (!vma) {
- dprintk(1, "no vma for address %lu\n", vaddr);
- goto userptr_fail_find_vma;
- }
-
- if (vma->vm_end < vaddr + size) {
- dprintk(1, "vma at %lu is too small for %lu bytes\n",
- vaddr, size);
- goto userptr_fail_find_vma;
- }
-
- buf->vma = vb2_get_vma(vma);
- if (!buf->vma) {
- dprintk(1, "failed to copy vma\n");
- goto userptr_fail_find_vma;
- }
-
- if (vma_is_io(buf->vma)) {
- for (num_pages_from_user = 0;
- num_pages_from_user < buf->num_pages;
- ++num_pages_from_user, vaddr += PAGE_SIZE) {
- unsigned long pfn;
-
- if (follow_pfn(vma, vaddr, &pfn)) {
- dprintk(1, "no page for address %lu\n", vaddr);
- break;
- }
- buf->pages[num_pages_from_user] = pfn_to_page(pfn);
- }
- } else
- num_pages_from_user = get_user_pages(current, current->mm,
- vaddr & PAGE_MASK,
- buf->num_pages,
- buf->dma_dir == DMA_FROM_DEVICE,
- 1, /* force */
- buf->pages,
- NULL);
- up_read(&current->mm->mmap_sem);
-
- if (num_pages_from_user != buf->num_pages)
- goto userptr_fail_get_user_pages;
+ buf->pages = frame_vector_pages(vec);
+ if (IS_ERR(buf->pages))
+ goto userptr_fail_sgtable;
+ buf->num_pages = frame_vector_count(vec);

if (sg_alloc_table_from_pages(buf->dma_sgt, buf->pages,
buf->num_pages, buf->offset, size, 0))
- goto userptr_fail_alloc_table_from_pages;
+ goto userptr_fail_sgtable;

sgt = &buf->sg_table;
/*
@@ -326,19 +274,9 @@ static void *vb2_dma_sg_get_userptr(void *alloc_ctx, unsigned long vaddr,

userptr_fail_map:
sg_free_table(&buf->sg_table);
-userptr_fail_alloc_table_from_pages:
-userptr_fail_get_user_pages:
- dprintk(1, "get_user_pages requested/got: %d/%d]\n",
- buf->num_pages, num_pages_from_user);
- if (!vma_is_io(buf->vma))
- while (--num_pages_from_user >= 0)
- put_page(buf->pages[num_pages_from_user]);
- down_read(&current->mm->mmap_sem);
- vb2_put_vma(buf->vma);
-userptr_fail_find_vma:
- up_read(&current->mm->mmap_sem);
- kfree(buf->pages);
-userptr_fail_alloc_pages:
+userptr_fail_sgtable:
+ vb2_destroy_framevec(vec);
+userptr_fail_pfnvec:
kfree(buf);
return NULL;
}
@@ -366,11 +304,8 @@ static void vb2_dma_sg_put_userptr(void *buf_priv)
while (--i >= 0) {
if (buf->dma_dir == DMA_FROM_DEVICE)
set_page_dirty_lock(buf->pages[i]);
- if (!vma_is_io(buf->vma))
- put_page(buf->pages[i]);
}
- kfree(buf->pages);
- vb2_put_vma(buf->vma);
+ vb2_destroy_framevec(buf->vec);
kfree(buf);
}

--
2.1.4