V4L/DVB: videobuf: rename videobuf_mmap_free and add sanity checks

This function is not specific to mmap, hence the rename.
Add a check whether we are not streaming or reading (for read mode that
uses the stream queue) before freeing anything.

Signed-off-by: Pawel Osciak <p.osciak@samsung.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c
index 4d565838795586feb9de8cb6372f3b4fa379b615..ce1595bef6291acea2af5b570c310eeb455aaf3d 100644 (file)
--- a/drivers/media/video/videobuf-core.c
+++ b/drivers/media/video/videobuf-core.c
@@ -195,6 +195,45 @@ int videobuf_queue_is_busy(struct videobuf_queue *q)
 }
 EXPORT_SYMBOL_GPL(videobuf_queue_is_busy);
 
+/**
+ * __videobuf_free() - free all the buffers and their control structures
+ *
+ * This function can only be called if streaming/reading is off, i.e. no buffers
+ * are under control of the driver.
+ */
+/* Locking: Caller holds q->vb_lock */
+static int __videobuf_free(struct videobuf_queue *q)
+{
+       int i;
+
+       dprintk(1, "%s\n", __func__);
+       if (!q)
+               return 0;
+
+       if (q->streaming || q->reading) {
+               dprintk(1, "Cannot free buffers when streaming or reading\n");
+               return -EBUSY;
+       }
+
+       MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
+
+       for (i = 0; i < VIDEO_MAX_FRAME; i++)
+               if (q->bufs[i] && q->bufs[i]->map) {
+                       dprintk(1, "Cannot free mmapped buffers\n");
+                       return -EBUSY;
+               }
+
+       for (i = 0; i < VIDEO_MAX_FRAME; i++) {
+               if (NULL == q->bufs[i])
+                       continue;
+               q->ops->buf_release(q, q->bufs[i]);
+               kfree(q->bufs[i]);
+               q->bufs[i] = NULL;
+       }
+
+       return 0;
+}
+
 /* Locking: Caller holds q->vb_lock */
 void videobuf_queue_cancel(struct videobuf_queue *q)
 {
@@ -308,36 +347,11 @@ static void videobuf_status(struct videobuf_queue *q, struct v4l2_buffer *b,
        b->sequence  = vb->field_count >> 1;
 }
 
-/* Locking: Caller holds q->vb_lock */
-static int __videobuf_mmap_free(struct videobuf_queue *q)
-{
-       int i;
-
-       if (!q)
-               return 0;
-
-       MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
-
-       for (i = 0; i < VIDEO_MAX_FRAME; i++)
-               if (q->bufs[i] && q->bufs[i]->map)
-                       return -EBUSY;
-
-       for (i = 0; i < VIDEO_MAX_FRAME; i++) {
-               if (NULL == q->bufs[i])
-                       continue;
-               q->ops->buf_release(q, q->bufs[i]);
-               kfree(q->bufs[i]);
-               q->bufs[i] = NULL;
-       }
-
-       return 0;
-}
-
 int videobuf_mmap_free(struct videobuf_queue *q)
 {
        int ret;
        mutex_lock(&q->vb_lock);
-       ret = __videobuf_mmap_free(q);
+       ret = __videobuf_free(q);
        mutex_unlock(&q->vb_lock);
        return ret;
 }
@@ -353,7 +367,7 @@ int __videobuf_mmap_setup(struct videobuf_queue *q,
 
        MAGIC_CHECK(q->int_ops->magic, MAGIC_QTYPE_OPS);
 
-       err = __videobuf_mmap_free(q);
+       err = __videobuf_free(q);
        if (0 != err)
                return err;
 
@@ -970,7 +984,7 @@ static void __videobuf_read_stop(struct videobuf_queue *q)
        int i;
 
        videobuf_queue_cancel(q);
-       __videobuf_mmap_free(q);
+       __videobuf_free(q);
        INIT_LIST_HEAD(&q->stream);
        for (i = 0; i < VIDEO_MAX_FRAME; i++) {
                if (NULL == q->bufs[i])