[media] videobuf2: add gfp_flags

Some drivers have special memory requirements for their buffers, usually
related to DMA (e.g. GFP_DMA or __GFP_DMA32). Make it possible to specify
additional GFP flags for those buffers by adding a gfp_flags field to
vb2_queue.
Note that this field will be replaced in the future with a different
mechanism, but that is still work in progress and we need this feature
now so we won't be able to convert drivers with such requirements to vb2.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Acked-by: Federico Vaga <federico.vaga@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

5 files changed, 17 insertions, 9 deletions

diff --git a/drivers/media/v4l2-core/videobuf2-core.c b/drivers/media/v4l2-core/videobuf2-core.c
index be0448161c60..70827feb87b4 100644
--- a/drivers/media/v4l2-core/videobuf2-core.c
+++ b/drivers/media/v4l2-core/videobuf2-core.c
@@ -57,7 +57,7 @@ static int __vb2_buf_mem_alloc(struct vb2_buffer *vb)
         /* Allocate memory for all planes in this buffer */
         for (plane = 0; plane < vb->num_planes; ++plane) {
                 mem_priv = call_memop(q, alloc, q->alloc_ctx[plane],
-                                      q->plane_sizes[plane]);
+                                      q->plane_sizes[plane], q->gfp_flags);
                 if (IS_ERR_OR_NULL(mem_priv))
                         goto free;
 
diff --git a/drivers/media/v4l2-core/videobuf2-dma-contig.c b/drivers/media/v4l2-core/videobuf2-dma-contig.c
index 10beaee7f0ae..ae35d255a430 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-contig.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-contig.c
@@ -152,7 +152,7 @@ static void vb2_dc_put(void *buf_priv)
         kfree(buf);
 }
 
-static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size)
+static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_flags)
 {
         struct vb2_dc_conf *conf = alloc_ctx;
         struct device *dev = conf->dev;
@@ -165,7 +165,8 @@ static void *vb2_dc_alloc(void *alloc_ctx, unsigned long size)
         /* align image size to PAGE_SIZE */
         size = PAGE_ALIGN(size);
 
-        buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr, GFP_KERNEL);
+        buf->vaddr = dma_alloc_coherent(dev, size, &buf->dma_addr,
+                                                GFP_KERNEL | gfp_flags);
         if (!buf->vaddr) {
                 dev_err(dev, "dma_alloc_coherent of size %ld failed\n", size);
                 kfree(buf);
diff --git a/drivers/media/v4l2-core/videobuf2-dma-sg.c b/drivers/media/v4l2-core/videobuf2-dma-sg.c
index 25c3b360e1ad..952776fafe2c 100644
--- a/drivers/media/v4l2-core/videobuf2-dma-sg.c
+++ b/drivers/media/v4l2-core/videobuf2-dma-sg.c
@@ -33,7 +33,7 @@ struct vb2_dma_sg_buf {
 
 static void vb2_dma_sg_put(void *buf_priv);
 
-static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size)
+static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_flags)
 {
         struct vb2_dma_sg_buf *buf;
         int i;
@@ -60,7 +60,8 @@ static void *vb2_dma_sg_alloc(void *alloc_ctx, unsigned long size)
                 goto fail_pages_array_alloc;
 
         for (i = 0; i < buf->sg_desc.num_pages; ++i) {
-                buf->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN);
+                buf->pages[i] = alloc_page(GFP_KERNEL | __GFP_ZERO |
+                                           __GFP_NOWARN | gfp_flags);
                 if (NULL == buf->pages[i])
                         goto fail_pages_alloc;
                 sg_set_page(&buf->sg_desc.sglist[i],
diff --git a/drivers/media/v4l2-core/videobuf2-vmalloc.c b/drivers/media/v4l2-core/videobuf2-vmalloc.c
index a47fd4f589a1..313d9771b2bc 100644
--- a/drivers/media/v4l2-core/videobuf2-vmalloc.c
+++ b/drivers/media/v4l2-core/videobuf2-vmalloc.c
@@ -35,11 +35,11 @@ struct vb2_vmalloc_buf {
 
 static void vb2_vmalloc_put(void *buf_priv);
 
-static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size)
+static void *vb2_vmalloc_alloc(void *alloc_ctx, unsigned long size, gfp_t gfp_flags)
 {
         struct vb2_vmalloc_buf *buf;
 
-        buf = kzalloc(sizeof(*buf), GFP_KERNEL);
+        buf = kzalloc(sizeof(*buf), GFP_KERNEL | gfp_flags);
         if (!buf)
                 return NULL;
 
diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h
index a2d427450780..d88a098d1aff 100644
--- a/include/media/videobuf2-core.h
+++ b/include/media/videobuf2-core.h
@@ -27,7 +27,9 @@ struct vb2_fileio_data;
  *              return NULL on failure or a pointer to allocator private,
  *              per-buffer data on success; the returned private structure
  *              will then be passed as buf_priv argument to other ops in this
- *              structure
+ *              structure. Additional gfp_flags to use when allocating the
+ *              are also passed to this operation. These flags are from the
+ *              gfp_flags field of vb2_queue.
  * @put:        inform the allocator that the buffer will no longer be used;
  *              usually will result in the allocator freeing the buffer (if
  *              no other users of this buffer are present); the buf_priv
@@ -79,7 +81,7 @@ struct vb2_fileio_data;
  *                                unmap_dmabuf.
  */
 struct vb2_mem_ops {
-        void            *(*alloc)(void *alloc_ctx, unsigned long size);
+        void            *(*alloc)(void *alloc_ctx, unsigned long size, gfp_t gfp_flags);
         void            (*put)(void *buf_priv);
         struct dma_buf *(*get_dmabuf)(void *buf_priv);
 
@@ -302,6 +304,9 @@ struct v4l2_fh;
  * @buf_struct_size: size of the driver-specific buffer structure;
  *              "0" indicates the driver doesn't want to use a custom buffer
  *              structure type, so sizeof(struct vb2_buffer) will is used
+ * @gfp_flags:  additional gfp flags used when allocating the buffers.
+ *              Typically this is 0, but it may be e.g. GFP_DMA or __GFP_DMA32
+ *              to force the buffer allocation to a specific memory zone.
  *
  * @memory:     current memory type used
  * @bufs:       videobuf buffer structures
@@ -327,6 +332,7 @@ struct vb2_queue {
         void                            *drv_priv;
         unsigned int                    buf_struct_size;
         u32                             timestamp_type;
+        gfp_t                           gfp_flags;
 
 /* private: internal use only */
         enum v4l2_memory                memory;