V4L/DVB (9111): cx18: Up the version to 1.0.1
[safe/jmp/linux-2.6] / drivers / media / video / cx18 / cx18-queue.c
index 4ef6996..a33ba04 100644 (file)
 #include "cx18-queue.h"
 #include "cx18-scb.h"
 
-int cx18_buf_copy_from_user(struct cx18_stream *s, struct cx18_buffer *buf,
-               const char __user *src, int copybytes)
-{
-       if (s->buf_size - buf->bytesused < copybytes)
-               copybytes = s->buf_size - buf->bytesused;
-       if (copy_from_user(buf->buf + buf->bytesused, src, copybytes))
-               return -EFAULT;
-       buf->bytesused += copybytes;
-       return copybytes;
-}
-
 void cx18_buf_swap(struct cx18_buffer *buf)
 {
        int i;
@@ -48,8 +37,7 @@ void cx18_buf_swap(struct cx18_buffer *buf)
 void cx18_queue_init(struct cx18_queue *q)
 {
        INIT_LIST_HEAD(&q->list);
-       q->buffers = 0;
-       q->length = 0;
+       atomic_set(&q->buffers, 0);
        q->bytesused = 0;
 }
 
@@ -66,8 +54,7 @@ void cx18_enqueue(struct cx18_stream *s, struct cx18_buffer *buf,
        }
        spin_lock_irqsave(&s->qlock, flags);
        list_add_tail(&buf->list, &q->list);
-       q->buffers++;
-       q->length += s->buf_size;
+       atomic_inc(&q->buffers);
        q->bytesused += buf->bytesused - buf->readpos;
        spin_unlock_irqrestore(&s->qlock, flags);
 }
@@ -81,20 +68,20 @@ struct cx18_buffer *cx18_dequeue(struct cx18_stream *s, struct cx18_queue *q)
        if (!list_empty(&q->list)) {
                buf = list_entry(q->list.next, struct cx18_buffer, list);
                list_del_init(q->list.next);
-               q->buffers--;
-               q->length -= s->buf_size;
+               atomic_dec(&q->buffers);
                q->bytesused -= buf->bytesused - buf->readpos;
        }
        spin_unlock_irqrestore(&s->qlock, flags);
        return buf;
 }
 
-struct cx18_buffer *cx18_queue_find_buf(struct cx18_stream *s, u32 id,
+struct cx18_buffer *cx18_queue_get_buf_irq(struct cx18_stream *s, u32 id,
        u32 bytesused)
 {
        struct cx18 *cx = s->cx;
        struct list_head *p;
 
+       spin_lock(&s->qlock);
        list_for_each(p, &s->q_free.list) {
                struct cx18_buffer *buf =
                        list_entry(p, struct cx18_buffer, list);
@@ -103,113 +90,45 @@ struct cx18_buffer *cx18_queue_find_buf(struct cx18_stream *s, u32 id,
                        continue;
                buf->bytesused = bytesused;
                /* the transport buffers are handled differently,
-                  so there is no need to move them to the full queue */
-               if (s->type == CX18_ENC_STREAM_TYPE_TS)
-                       return buf;
-               s->q_free.buffers--;
-               s->q_free.length -= s->buf_size;
-               s->q_full.buffers++;
-               s->q_full.length += s->buf_size;
-               s->q_full.bytesused += buf->bytesused;
-               list_move_tail(&buf->list, &s->q_full.list);
+                  they are not moved to the full queue */
+               if (s->type != CX18_ENC_STREAM_TYPE_TS) {
+                       atomic_dec(&s->q_free.buffers);
+                       atomic_inc(&s->q_full.buffers);
+                       s->q_full.bytesused += buf->bytesused;
+                       list_move_tail(&buf->list, &s->q_full.list);
+               }
+               spin_unlock(&s->qlock);
                return buf;
        }
+       spin_unlock(&s->qlock);
        CX18_ERR("Cannot find buffer %d for stream %s\n", id, s->name);
        return NULL;
 }
 
-static void cx18_queue_move_buf(struct cx18_stream *s, struct cx18_queue *from,
-               struct cx18_queue *to, int clear, int full)
-{
-       struct cx18_buffer *buf =
-               list_entry(from->list.next, struct cx18_buffer, list);
-
-       list_move_tail(from->list.next, &to->list);
-       from->buffers--;
-       from->length -= s->buf_size;
-       from->bytesused -= buf->bytesused - buf->readpos;
-       /* special handling for q_free */
-       if (clear)
-               buf->bytesused = buf->readpos = buf->b_flags = 0;
-       else if (full) {
-               /* special handling for stolen buffers, assume
-                  all bytes are used. */
-               buf->bytesused = s->buf_size;
-               buf->readpos = buf->b_flags = 0;
-       }
-       to->buffers++;
-       to->length += s->buf_size;
-       to->bytesused += buf->bytesused - buf->readpos;
-}
-
-/* Move 'needed_bytes' worth of buffers from queue 'from' into queue 'to'.
-   If 'needed_bytes' == 0, then move all buffers from 'from' into 'to'.
-   If 'steal' != NULL, then buffers may also taken from that queue if
-   needed.
-
-   The buffer is automatically cleared if it goes to the free queue. It is
-   also cleared if buffers need to be taken from the 'steal' queue and
-   the 'from' queue is the free queue.
-
-   When 'from' is q_free, then needed_bytes is compared to the total
-   available buffer length, otherwise needed_bytes is compared to the
-   bytesused value. For the 'steal' queue the total available buffer
-   length is always used.
-
-   -ENOMEM is returned if the buffers could not be obtained, 0 if all
-   buffers where obtained from the 'from' list and if non-zero then
-   the number of stolen buffers is returned. */
-int cx18_queue_move(struct cx18_stream *s, struct cx18_queue *from,
-       struct cx18_queue *steal, struct cx18_queue *to, int needed_bytes)
+/* Move all buffers of a queue to q_free, while flushing the buffers */
+static void cx18_queue_flush(struct cx18_stream *s, struct cx18_queue *q)
 {
        unsigned long flags;
-       int rc = 0;
-       int from_free = from == &s->q_free;
-       int to_free = to == &s->q_free;
-       int bytes_available;
-
-       spin_lock_irqsave(&s->qlock, flags);
-       if (needed_bytes == 0) {
-               from_free = 1;
-               needed_bytes = from->length;
-       }
-
-       bytes_available = from_free ? from->length : from->bytesused;
-       bytes_available += steal ? steal->length : 0;
-
-       if (bytes_available < needed_bytes) {
-               spin_unlock_irqrestore(&s->qlock, flags);
-               return -ENOMEM;
-       }
-       if (from_free) {
-               u32 old_length = to->length;
+       struct cx18_buffer *buf;
 
-               while (to->length - old_length < needed_bytes) {
-                       if (list_empty(&from->list))
-                               from = steal;
-                       if (from == steal)
-                               rc++;   /* keep track of 'stolen' buffers */
-                       cx18_queue_move_buf(s, from, to, 1, 0);
-               }
-       } else {
-               u32 old_bytesused = to->bytesused;
+       if (q == &s->q_free)
+               return;
 
-               while (to->bytesused - old_bytesused < needed_bytes) {
-                       if (list_empty(&from->list))
-                               from = steal;
-                       if (from == steal)
-                               rc++;   /* keep track of 'stolen' buffers */
-                       cx18_queue_move_buf(s, from, to, to_free, rc);
-               }
+       spin_lock_irqsave(&s->qlock, flags);
+       while (!list_empty(&q->list)) {
+               buf = list_entry(q->list.next, struct cx18_buffer, list);
+               list_move_tail(q->list.next, &s->q_free.list);
+               buf->bytesused = buf->readpos = buf->b_flags = 0;
+               atomic_inc(&s->q_free.buffers);
        }
+       cx18_queue_init(q);
        spin_unlock_irqrestore(&s->qlock, flags);
-       return rc;
 }
 
 void cx18_flush_queues(struct cx18_stream *s)
 {
-       cx18_queue_move(s, &s->q_io, NULL, &s->q_free, 0);
-       cx18_queue_move(s, &s->q_full, NULL, &s->q_free, 0);
+       cx18_queue_flush(s, &s->q_io);
+       cx18_queue_flush(s, &s->q_full);
 }
 
 int cx18_stream_alloc(struct cx18_stream *s)
@@ -224,10 +143,10 @@ int cx18_stream_alloc(struct cx18_stream *s)
                s->name, s->buffers, s->buf_size,
                s->buffers * s->buf_size / 1024);
 
-       if (((char *)&cx->scb->cpu_mdl[cx->mdl_offset + s->buffers] -
-                               (char *)cx->scb) > SCB_RESERVED_SIZE) {
-               unsigned bufsz = (((char *)cx->scb) + SCB_RESERVED_SIZE -
-                                       ((char *)cx->scb->cpu_mdl));
+       if (((char __iomem *)&cx->scb->cpu_mdl[cx->mdl_offset + s->buffers] -
+                               (char __iomem *)cx->scb) > SCB_RESERVED_SIZE) {
+               unsigned bufsz = (((char __iomem *)cx->scb) + SCB_RESERVED_SIZE -
+                                       ((char __iomem *)cx->scb->cpu_mdl));
 
                CX18_ERR("Too many buffers, cannot fit in SCB area\n");
                CX18_ERR("Max buffers = %zd\n",