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>

5 files changed, 67 insertions, 92 deletions

diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c
index f1dfcff44e1..dc2f6a8c022 100644
--- a/drivers/media/video/videobuf-core.c
+++ b/drivers/media/video/videobuf-core.c
@@ -1123,15 +1123,29 @@ EXPORT_SYMBOL_GPL(videobuf_poll_stream);
 
 int videobuf_mmap_mapper(struct videobuf_queue *q, struct vm_area_struct *vma)
 {
-        int retval;
+        int rc = -EINVAL;
+        int i;
 
         MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
 
+        if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED)) {
+                dprintk(1, "mmap appl bug: PROT_WRITE and MAP_SHARED are required\n");
+                return -EINVAL;
+        }
+
         mutex_lock(&q->vb_lock);
-        retval = CALL(q, mmap_mapper, q, vma);
+        for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+                struct videobuf_buffer *buf = q->bufs[i];
+
+                if (buf && buf->memory == V4L2_MEMORY_MMAP &&
+                                buf->boff == (vma->vm_pgoff << PAGE_SHIFT)) {
+                        rc = CALL(q, mmap_mapper, q, buf, vma);
+                        break;
+                }
+        }
         mutex_unlock(&q->vb_lock);
 
-        return retval;
+        return rc;
 }
 EXPORT_SYMBOL_GPL(videobuf_mmap_mapper);
 
diff --git a/drivers/media/video/videobuf-dma-contig.c b/drivers/media/video/videobuf-dma-contig.c
index 0a0ff85140b..055ce8439ce 100644
--- a/drivers/media/video/videobuf-dma-contig.c
+++ b/drivers/media/video/videobuf-dma-contig.c
@@ -264,51 +264,33 @@ static int __videobuf_iolock(struct videobuf_queue *q,
 }
 
 static int __videobuf_mmap_mapper(struct videobuf_queue *q,
+                                  struct videobuf_buffer *buf,
                                   struct vm_area_struct *vma)
 {
         struct videobuf_dma_contig_memory *mem;
         struct videobuf_mapping *map;
-        unsigned int first;
         int retval;
-        unsigned long size, offset = vma->vm_pgoff << PAGE_SHIFT;
+        unsigned long size;
 
         dev_dbg(q->dev, "%s\n", __func__);
-        if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED))
-                return -EINVAL;
-
-        /* look for first buffer to map */
-        for (first = 0; first < VIDEO_MAX_FRAME; first++) {
-                if (!q->bufs[first])
-                        continue;
-
-                if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
-                        continue;
-                if (q->bufs[first]->boff == offset)
-                        break;
-        }
-        if (VIDEO_MAX_FRAME == first) {
-                dev_dbg(q->dev, "invalid user space offset [offset=0x%lx]\n",
-                        offset);
-                return -EINVAL;
-        }
 
         /* create mapping + update buffer list */
         map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
         if (!map)
                 return -ENOMEM;
 
-        q->bufs[first]->map = map;
+        buf->map = map;
         map->start = vma->vm_start;
         map->end = vma->vm_end;
         map->q = q;
 
-        q->bufs[first]->baddr = vma->vm_start;
+        buf->baddr = vma->vm_start;
 
-        mem = q->bufs[first]->priv;
+        mem = buf->priv;
         BUG_ON(!mem);
         MAGIC_CHECK(mem->magic, MAGIC_DC_MEM);
 
-        mem->size = PAGE_ALIGN(q->bufs[first]->bsize);
+        mem->size = PAGE_ALIGN(buf->bsize);
         mem->vaddr = dma_alloc_coherent(q->dev, mem->size,
                                         &mem->dma_handle, GFP_KERNEL);
         if (!mem->vaddr) {
@@ -341,8 +323,8 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
 
         dev_dbg(q->dev, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
                 map, q, vma->vm_start, vma->vm_end,
-                (long int) q->bufs[first]->bsize,
-                vma->vm_pgoff, first);
+                (long int)buf->bsize,
+                vma->vm_pgoff, buf->i);
 
         videobuf_vm_open(vma);
 
diff --git a/drivers/media/video/videobuf-dma-sg.c b/drivers/media/video/videobuf-dma-sg.c
index 5c55bd392ea..1a7f3d3d2f9 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;
diff --git a/drivers/media/video/videobuf-vmalloc.c b/drivers/media/video/videobuf-vmalloc.c
index ad655839827..f8b5b563511 100644
--- a/drivers/media/video/videobuf-vmalloc.c
+++ b/drivers/media/video/videobuf-vmalloc.c
@@ -236,47 +236,28 @@ 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_vmalloc_memory *mem;
         struct videobuf_mapping *map;
-        unsigned int first;
         int retval, pages;
-        unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
 
         dprintk(1, "%s\n", __func__);
-        if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED))
-                return -EINVAL;
-
-        /* look for first buffer to map */
-        for (first = 0; first < VIDEO_MAX_FRAME; first++) {
-                if (NULL == q->bufs[first])
-                        continue;
-
-                if (V4L2_MEMORY_MMAP != q->bufs[first]->memory)
-                        continue;
-                if (q->bufs[first]->boff == offset)
-                        break;
-        }
-        if (VIDEO_MAX_FRAME == first) {
-                dprintk(1, "mmap app bug: offset invalid [offset=0x%lx]\n",
-                        (vma->vm_pgoff << PAGE_SHIFT));
-                return -EINVAL;
-        }
 
         /* create mapping + update buffer list */
         map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
         if (NULL == map)
                 return -ENOMEM;
 
-        q->bufs[first]->map = map;
+        buf->map = map;
         map->start = vma->vm_start;
         map->end   = vma->vm_end;
         map->q     = q;
 
-        q->bufs[first]->baddr = vma->vm_start;
+        buf->baddr = vma->vm_start;
 
-        mem = q->bufs[first]->priv;
+        mem = buf->priv;
         BUG_ON(!mem);
         MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
 
@@ -302,8 +283,8 @@ static int __videobuf_mmap_mapper(struct videobuf_queue *q,
 
         dprintk(1, "mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
                 map, q, vma->vm_start, vma->vm_end,
-                (long int) q->bufs[first]->bsize,
-                vma->vm_pgoff, first);
+                (long int)buf->bsize,
+                vma->vm_pgoff, buf->i);
 
         videobuf_vm_open(vma);
 
diff --git a/include/media/videobuf-core.h b/include/media/videobuf-core.h
index 821a530f495..f91a736c133 100644
--- a/include/media/videobuf-core.h
+++ b/include/media/videobuf-core.h
@@ -135,7 +135,8 @@ struct videobuf_qtype_ops {
         int (*sync)             (struct videobuf_queue *q,
                                  struct videobuf_buffer *buf);
         int (*mmap_mapper)      (struct videobuf_queue *q,
-                                struct vm_area_struct *vma);
+                                 struct videobuf_buffer *buf,
+                                 struct vm_area_struct *vma);
 };
 
 struct videobuf_queue {