V4L/DVB (7561): videobuf-vmalloc: stop streaming before unmap

Before the patch, there were a risk of freeing and unmapping userspace memory,
while there were pending requests.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
This commit is contained in:
Mauro Carvalho Chehab 2008-04-13 15:07:56 -03:00
parent d684965262
commit aa9479ed50
2 changed files with 19 additions and 5 deletions

View file

@ -901,7 +901,6 @@ static void __videobuf_read_stop(struct videobuf_queue *q)
{
int i;
videobuf_queue_cancel(q);
__videobuf_mmap_free(q);
INIT_LIST_HEAD(&q->stream);

View file

@ -72,6 +72,11 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
dprintk(1, "munmap %p q=%p\n", map, q);
mutex_lock(&q->vb_lock);
/* We need first to cancel streams, before unmapping */
if (q->streaming)
videobuf_queue_cancel(q);
for (i = 0; i < VIDEO_MAX_FRAME; i++) {
if (NULL == q->bufs[i])
continue;
@ -86,7 +91,15 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
In this case, memory should be freed,
in order to do memory unmap.
*/
MAGIC_CHECK(mem->magic, MAGIC_VMAL_MEM);
/* vfree is not atomic - can't be
called with IRQ's disabled
*/
dprintk(1, "%s: buf[%d] freeing (%p)\n",
__func__, i, mem->vmalloc);
vfree(mem->vmalloc);
mem->vmalloc = NULL;
}
@ -94,9 +107,12 @@ static void videobuf_vm_close(struct vm_area_struct *vma)
q->bufs[i]->map = NULL;
q->bufs[i]->baddr = 0;
}
mutex_unlock(&q->vb_lock);
kfree(map);
mutex_unlock(&q->vb_lock);
}
return;
}
@ -138,6 +154,7 @@ static int __videobuf_iolock (struct videobuf_queue* q,
struct v4l2_framebuffer *fbuf)
{
struct videobuf_vmalloc_memory *mem = vb->priv;
int pages;
BUG_ON(!mem);
@ -154,8 +171,7 @@ static int __videobuf_iolock (struct videobuf_queue* q,
}
break;
case V4L2_MEMORY_USERPTR:
{
int pages = PAGE_ALIGN(vb->size);
pages = PAGE_ALIGN(vb->size);
dprintk(1, "%s memory method USERPTR\n", __func__);
@ -198,7 +214,6 @@ static int __videobuf_iolock (struct videobuf_queue* q,
#endif
break;
}
case V4L2_MEMORY_OVERLAY:
default:
dprintk(1, "%s memory method OVERLAY/unknown\n", __func__);