V4L/DVB (7552): videbuf-vmalloc: Corrects mmap code
There were some bugs on videobuf-vmalloc.
Basically, remap were called with a wrong parameter. Due to that, a later remap
were needed, generating the need of some hacks on videobuf-vmalloc and
videobuf-core.
This patch fixes the remap and removes the hacks.
TODO:
- V4L2_MEMORY_USERPTR is not implemented yet. This method should be
properly implemented, in order to work with a few userspace applications.
- The driver also doesn't implement V4L2_MEMORY_OVERLAY. This method is used
only by a few applications, and are becaming obsolete, due to the increment
of cpu performance. So, most apps prefer to retrieve data to an internal
buffer, doing some processing like de-interlacing.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/video/videobuf-vmalloc.c b/drivers/media/video/videobuf-vmalloc.c
index 9eb7982..075acdf 100644
--- a/drivers/media/video/videobuf-vmalloc.c
+++ b/drivers/media/video/videobuf-vmalloc.c
@@ -124,45 +124,75 @@
struct videobuf_buffer *vb,
struct v4l2_framebuffer *fbuf)
{
- int pages;
- struct videobuf_vmalloc_memory *mem=vb->priv;
+ struct videobuf_vmalloc_memory *mem = vb->priv;
BUG_ON(!mem);
- MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+ MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
- pages = PAGE_ALIGN(vb->size) >> PAGE_SHIFT;
+ switch (vb->memory) {
+ case V4L2_MEMORY_MMAP:
+ dprintk(1, "%s memory method MMAP\n", __func__);
- /* Currently, doesn't support V4L2_MEMORY_OVERLAY */
- if ((vb->memory != V4L2_MEMORY_MMAP) &&
- (vb->memory != V4L2_MEMORY_USERPTR) ) {
- printk(KERN_ERR "Method currently unsupported.\n");
- return -EINVAL;
- }
-
- /* FIXME: should be tested with kernel mmap mem */
- mem->vmalloc=vmalloc_user (PAGE_ALIGN(vb->size));
- if (NULL == mem->vmalloc) {
- printk(KERN_ERR "vmalloc (%d pages) failed\n",pages);
- return -ENOMEM;
- }
-
- dprintk(1,"vmalloc is at addr 0x%08lx, size=%d\n",
- (unsigned long)mem->vmalloc,
- pages << PAGE_SHIFT);
-
- /* It seems that some kernel versions need to do remap *after*
- the mmap() call
- */
- if (mem->vma) {
- int retval=remap_vmalloc_range(mem->vma, mem->vmalloc,0);
- kfree(mem->vma);
- mem->vma=NULL;
- if (retval<0) {
- dprintk(1,"mmap app bug: remap_vmalloc_range area %p error %d\n",
- mem->vmalloc,retval);
- return retval;
+ /* All handling should be done by __videobuf_mmap_mapper() */
+ if (!mem->vmalloc) {
+ printk(KERN_ERR "memory is not alloced/mmapped.\n");
+ return -EINVAL;
}
+ break;
+ case V4L2_MEMORY_USERPTR:
+ {
+ int pages = PAGE_ALIGN(vb->size);
+
+ dprintk(1, "%s memory method USERPTR\n", __func__);
+
+#if 1
+ if (vb->baddr) {
+ printk(KERN_ERR "USERPTR is currently not supported\n");
+ return -EINVAL;
+ }
+#endif
+
+ /* The only USERPTR currently supported is the one needed for
+ read() method.
+ */
+
+ mem->vmalloc = vmalloc_user(pages);
+ if (!mem->vmalloc) {
+ printk(KERN_ERR "vmalloc (%d pages) failed\n", pages);
+ return -ENOMEM;
+ }
+ dprintk(1, "vmalloc is at addr %p (%d pages)\n",
+ mem->vmalloc, pages);
+
+#if 0
+ int rc;
+ /* Kernel userptr is used also by read() method. In this case,
+ there's no need to remap, since data will be copied to user
+ */
+ if (!vb->baddr)
+ return 0;
+
+ /* FIXME: to properly support USERPTR, remap should occur.
+ The code bellow won't work, since mem->vma = NULL
+ */
+ /* Try to remap memory */
+ rc = remap_vmalloc_range(mem->vma, (void *)vb->baddr, 0);
+ if (rc < 0) {
+ printk(KERN_ERR "mmap: remap failed with error %d. ", rc);
+ return -ENOMEM;
+ }
+#endif
+
+ break;
+ }
+ case V4L2_MEMORY_OVERLAY:
+ default:
+ dprintk(1, "%s memory method OVERLAY/unknown\n", __func__);
+
+ /* Currently, doesn't support V4L2_MEMORY_OVERLAY */
+ printk(KERN_ERR "Memory method currently unsupported.\n");
+ return -EINVAL;
}
return 0;
@@ -178,6 +208,7 @@
{
unsigned int i;
+ dprintk(1, "%s\n", __func__);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (q->bufs[i]) {
if (q->bufs[i]->map)
@@ -194,10 +225,11 @@
struct videobuf_vmalloc_memory *mem;
struct videobuf_mapping *map;
unsigned int first;
- int retval;
+ int retval, pages;
unsigned long offset = vma->vm_pgoff << PAGE_SHIFT;
- if (! (vma->vm_flags & VM_WRITE) || ! (vma->vm_flags & VM_SHARED))
+ dprintk(1, "%s\n", __func__);
+ if (!(vma->vm_flags & VM_WRITE) || !(vma->vm_flags & VM_SHARED))
return -EINVAL;
/* look for first buffer to map */
@@ -217,46 +249,55 @@
}
/* create mapping + update buffer list */
- map = q->bufs[first]->map = kzalloc(sizeof(struct videobuf_mapping),GFP_KERNEL);
+ map = kzalloc(sizeof(struct videobuf_mapping), GFP_KERNEL);
if (NULL == map)
return -ENOMEM;
+ q->bufs[first]->map = map;
map->start = vma->vm_start;
map->end = vma->vm_end;
map->q = q;
q->bufs[first]->baddr = vma->vm_start;
+ mem = q->bufs[first]->priv;
+ BUG_ON(!mem);
+ MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
+
+ pages = PAGE_ALIGN(vma->vm_end - vma->vm_start);
+ mem->vmalloc = vmalloc_user(pages);
+ if (!mem->vmalloc) {
+ printk(KERN_ERR "vmalloc (%d pages) failed\n", pages);
+ goto error;
+ }
+ dprintk(1, "vmalloc is at addr %p (%d pages)\n",
+ mem->vmalloc, pages);
+
+ /* Try to remap memory */
+ retval = remap_vmalloc_range(vma, mem->vmalloc, 0);
+ if (retval < 0) {
+ printk(KERN_ERR "mmap: remap failed with error %d. ", retval);
+ vfree(mem->vmalloc);
+ goto error;
+ }
+
vma->vm_ops = &videobuf_vm_ops;
vma->vm_flags |= VM_DONTEXPAND | VM_RESERVED;
vma->vm_private_data = map;
- mem=q->bufs[first]->priv;
- BUG_ON (!mem);
- MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
-
- /* Try to remap memory */
- retval=remap_vmalloc_range(vma, mem->vmalloc,0);
- if (retval<0) {
- dprintk(1,"mmap: postponing remap_vmalloc_range\n");
-
- mem->vma=kmalloc(sizeof(*vma),GFP_KERNEL);
- if (!mem->vma) {
- kfree(map);
- q->bufs[first]->map=NULL;
- return -ENOMEM;
- }
- memcpy(mem->vma,vma,sizeof(*vma));
- }
-
dprintk(1,"mmap %p: q=%p %08lx-%08lx (%lx) pgoff %08lx buf %d\n",
- map,q,vma->vm_start,vma->vm_end,
+ map, q, vma->vm_start, vma->vm_end,
(long int) q->bufs[first]->bsize,
- vma->vm_pgoff,first);
+ vma->vm_pgoff, first);
videobuf_vm_open(vma);
- return (0);
+ return 0;
+
+error:
+ mem = NULL;
+ kfree(map);
+ return -ENOMEM;
}
static int __videobuf_copy_to_user ( struct videobuf_queue *q,
@@ -347,13 +388,19 @@
void videobuf_vmalloc_free (struct videobuf_buffer *buf)
{
- struct videobuf_vmalloc_memory *mem=buf->priv;
- BUG_ON (!mem);
+ struct videobuf_vmalloc_memory *mem = buf->priv;
- MAGIC_CHECK(mem->magic,MAGIC_VMAL_MEM);
+ if (!mem)
+ return;
+
+ MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
vfree(mem->vmalloc);
- mem->vmalloc=NULL;
+ mem->vmalloc = NULL;
+
+
+
+ /* FIXME: need to do buf->priv = NULL? */
return;
}