V4L/DVB: v4l videobuf: add videobuf_buffer *buf as argument to mmap_mapper

mmap_mapper should operate on a buffer, not on a complete queue. So let
the videobuf-core find the correct buffer instead of duplicating that
code in each mmap_mapper implementation.

The dma-sg implementation has backwards compatibility code for handling
the V4L1_COMPAT layer. This code is now under the v4L1_COMPAT config option.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 33 insertions, 36 deletions

diff --git a/drivers/media/video/videobuf-dma-sg.c b/drivers/media/video/videobuf-dma-sg.c
index 5c55bd392ea3..1a7f3d3d2f99 100644
--- a/drivers/media/video/videobuf-dma-sg.c
+++ b/drivers/media/video/videobuf-dma-sg.c
@@ -549,22 +549,15 @@ static int __videobuf_sync(struct videobuf_queue *q,
 }
 
 static int __videobuf_mmap_mapper(struct videobuf_queue *q,
-                         struct vm_area_struct *vma)
+                                  struct videobuf_buffer *buf,
+                                  struct vm_area_struct *vma)
 {
-        struct videobuf_dma_sg_memory *mem;
+        struct videobuf_dma_sg_memory *mem = buf->priv;
         struct videobuf_mapping *map;
         unsigned int first, last, size, i;
         int retval;
 
         retval = -EINVAL;
-        if (!(vma->vm_flags & VM_WRITE)) {
-                dprintk(1, "mmap app bug: PROT_WRITE please\n");
-                goto done;
-        }
-        if (!(vma->vm_flags & VM_SHARED)) {
-                dprintk(1, "mmap app bug: MAP_SHARED please\n");
-                goto done;
-        }
 
         /* This function maintains backwards compatibility with V4L1 and will
          * map more than one buffer if the vma length is equal to the combined
@@ -574,44 +567,48 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
          * TODO: Allow drivers to specify if they support this mode
          */
 
+        BUG_ON(!mem);
+        MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
+
         /* look for first buffer to map */
         for (first = 0; first < VIDEO_MAX_FRAME; first++) {
-                if (NULL == q->bufs[first])
-                        continue;
-                mem = q->bufs[first]->priv;
-                BUG_ON(!mem);
-                MAGIC_CHECK(mem->magic, MAGIC_SG_MEM);
-
-                if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
-                        continue;
-                if (q->bufs[first]->boff == (vma->vm_pgoff << PAGE_SHIFT))
+                if (buf == q->bufs[first]) {
+                        size = PAGE_ALIGN(q->bufs[first]->bsize);
                         break;
+                }
         }
+
+        /* paranoia, should never happen since buf is always valid. */
         if (VIDEO_MAX_FRAME == first) {
                 dprintk(1, "mmap app bug: offset invalid [offset=0x%lx]\n",
-                        (vma->vm_pgoff << PAGE_SHIFT));
+                                (vma->vm_pgoff << PAGE_SHIFT));
                 goto done;
         }
 
-        /* look for last buffer to map */
-        for (size = 0, last = first; last < VIDEO_MAX_FRAME; last++) {
-                if (NULL == q->bufs[last])
-                        continue;
-                if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
-                        continue;
-                if (q->bufs[last]->map) {
-                        retval = -EBUSY;
+        last = first;
+#ifdef CONFIG_VIDEO_V4L1_COMPAT
+        if (size != (vma->vm_end - vma->vm_start)) {
+                /* look for last buffer to map */
+                for (last = first + 1; last < VIDEO_MAX_FRAME; last++) {
+                        if (NULL == q->bufs[last])
+                                continue;
+                        if (V4L2_MEMORY_MMAP != q->bufs[last]->memory)
+                                continue;
+                        if (q->bufs[last]->map) {
+                                retval = -EBUSY;
+                                goto done;
+                        }
+                        size += PAGE_ALIGN(q->bufs[last]->bsize);
+                        if (size == (vma->vm_end - vma->vm_start))
+                                break;
+                }
+                if (VIDEO_MAX_FRAME == last) {
+                        dprintk(1, "mmap app bug: size invalid [size=0x%lx]\n",
+                                        (vma->vm_end - vma->vm_start));
                         goto done;
                 }
-                size += PAGE_ALIGN(q->bufs[last]->bsize);
-                if (size == (vma->vm_end - vma->vm_start))
-                        break;
-        }
-        if (VIDEO_MAX_FRAME == last) {
-                dprintk(1, "mmap app bug: size invalid [size=0x%lx]\n",
-                        (vma->vm_end - vma->vm_start));
-                goto done;
         }
+#endif
 
         /* create mapping + update buffer list */
         retval = -ENOMEM;