--- /dev/null
+/*
+ buffer queues.
+ Copyright (C) 2003-2004 Kevin Thayer <nufan_wfk at yahoo.com>
+ Copyright (C) 2004 Chris Kennedy <c@groovy.org>
+ Copyright (C) 2005-2007 Hans Verkuil <hverkuil@xs4all.nl>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+
+#include "ivtv-driver.h"
+#include "ivtv-queue.h"
+
+int ivtv_buf_copy_from_user(struct ivtv_stream *s, struct ivtv_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 ivtv_buf_swap(struct ivtv_buffer *buf)
+{
+ int i;
+
+ for (i = 0; i < buf->bytesused; i += 4)
+ swab32s((u32 *)(buf->buf + i));
+}
+
+void ivtv_queue_init(struct ivtv_queue *q)
+{
+ INIT_LIST_HEAD(&q->list);
+ q->buffers = 0;
+ q->length = 0;
+ q->bytesused = 0;
+}
+
+void ivtv_enqueue(struct ivtv_stream *s, struct ivtv_buffer *buf, struct ivtv_queue *q)
+{
+ unsigned long flags;
+
+ /* clear the buffer if it is going to be enqueued to the free queue */
+ if (q == &s->q_free) {
+ buf->bytesused = 0;
+ buf->readpos = 0;
+ buf->b_flags = 0;
+ buf->dma_xfer_cnt = 0;
+ }
+ spin_lock_irqsave(&s->qlock, flags);
+ list_add_tail(&buf->list, &q->list);
+ q->buffers++;
+ q->length += s->buf_size;
+ q->bytesused += buf->bytesused - buf->readpos;
+ spin_unlock_irqrestore(&s->qlock, flags);
+}
+
+struct ivtv_buffer *ivtv_dequeue(struct ivtv_stream *s, struct ivtv_queue *q)
+{
+ struct ivtv_buffer *buf = NULL;
+ unsigned long flags;
+
+ spin_lock_irqsave(&s->qlock, flags);
+ if (!list_empty(&q->list)) {
+ buf = list_entry(q->list.next, struct ivtv_buffer, list);
+ list_del_init(q->list.next);
+ q->buffers--;
+ q->length -= s->buf_size;
+ q->bytesused -= buf->bytesused - buf->readpos;
+ }
+ spin_unlock_irqrestore(&s->qlock, flags);
+ return buf;
+}
+
+static void ivtv_queue_move_buf(struct ivtv_stream *s, struct ivtv_queue *from,
+ struct ivtv_queue *to, int clear)
+{
+ struct ivtv_buffer *buf = list_entry(from->list.next, struct ivtv_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 = buf->dma_xfer_cnt = 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, but only if 'from' is the free queue.
+
+ 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 ivtv_queue_move(struct ivtv_stream *s, struct ivtv_queue *from, struct ivtv_queue *steal,
+ struct ivtv_queue *to, int needed_bytes)
+{
+ unsigned long flags;
+ int rc = 0;
+ int from_free = from == &s->q_free;
+ int to_free = to == &s->q_free;
+ int bytes_available, bytes_steal;
+
+ 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_steal = (from_free && steal) ? steal->length : 0;
+
+ if (bytes_available + bytes_steal < needed_bytes) {
+ spin_unlock_irqrestore(&s->qlock, flags);
+ return -ENOMEM;
+ }
+ while (bytes_available < needed_bytes) {
+ struct ivtv_buffer *buf = list_entry(steal->list.prev, struct ivtv_buffer, list);
+ u16 dma_xfer_cnt = buf->dma_xfer_cnt;
+
+ /* move buffers from the tail of the 'steal' queue to the tail of the
+ 'from' queue. Always copy all the buffers with the same dma_xfer_cnt
+ value, this ensures that you do not end up with partial frame data
+ if one frame is stored in multiple buffers. */
+ while (dma_xfer_cnt == buf->dma_xfer_cnt) {
+ list_move_tail(steal->list.prev, &from->list);
+ rc++;
+ steal->buffers--;
+ steal->length -= s->buf_size;
+ steal->bytesused -= buf->bytesused - buf->readpos;
+ buf->bytesused = buf->readpos = buf->b_flags = buf->dma_xfer_cnt = 0;
+ from->buffers++;
+ from->length += s->buf_size;
+ bytes_available += s->buf_size;
+ if (list_empty(&steal->list))
+ break;
+ buf = list_entry(steal->list.prev, struct ivtv_buffer, list);
+ }
+ }
+ if (from_free) {
+ u32 old_length = to->length;
+
+ while (to->length - old_length < needed_bytes) {
+ ivtv_queue_move_buf(s, from, to, 1);
+ }
+ }
+ else {
+ u32 old_bytesused = to->bytesused;
+
+ while (to->bytesused - old_bytesused < needed_bytes) {
+ ivtv_queue_move_buf(s, from, to, to_free);
+ }
+ }
+ spin_unlock_irqrestore(&s->qlock, flags);
+ return rc;
+}
+
+void ivtv_flush_queues(struct ivtv_stream *s)
+{
+ ivtv_queue_move(s, &s->q_io, NULL, &s->q_free, 0);
+ ivtv_queue_move(s, &s->q_full, NULL, &s->q_free, 0);
+ ivtv_queue_move(s, &s->q_dma, NULL, &s->q_free, 0);
+ ivtv_queue_move(s, &s->q_predma, NULL, &s->q_free, 0);
+}
+
+int ivtv_stream_alloc(struct ivtv_stream *s)
+{
+ struct ivtv *itv = s->itv;
+ int SGsize = sizeof(struct ivtv_sg_host_element) * s->buffers;
+ int i;
+
+ if (s->buffers == 0)
+ return 0;
+
+ IVTV_DEBUG_INFO("Allocate %s%s stream: %d x %d buffers (%dkB total)\n",
+ s->dma != PCI_DMA_NONE ? "DMA " : "",
+ s->name, s->buffers, s->buf_size, s->buffers * s->buf_size / 1024);
+
+ s->sg_pending = kzalloc(SGsize, GFP_KERNEL|__GFP_NOWARN);
+ if (s->sg_pending == NULL) {
+ IVTV_ERR("Could not allocate sg_pending for %s stream\n", s->name);
+ return -ENOMEM;
+ }
+ s->sg_pending_size = 0;
+
+ s->sg_processing = kzalloc(SGsize, GFP_KERNEL|__GFP_NOWARN);
+ if (s->sg_processing == NULL) {
+ IVTV_ERR("Could not allocate sg_processing for %s stream\n", s->name);
+ kfree(s->sg_pending);
+ s->sg_pending = NULL;
+ return -ENOMEM;
+ }
+ s->sg_processing_size = 0;
+
+ s->sg_dma = kzalloc(sizeof(struct ivtv_sg_element),
+ GFP_KERNEL|__GFP_NOWARN);
+ if (s->sg_dma == NULL) {
+ IVTV_ERR("Could not allocate sg_dma for %s stream\n", s->name);
+ kfree(s->sg_pending);
+ s->sg_pending = NULL;
+ kfree(s->sg_processing);
+ s->sg_processing = NULL;
+ return -ENOMEM;
+ }
+ if (ivtv_might_use_dma(s)) {
+ s->sg_handle = pci_map_single(itv->pdev, s->sg_dma,
+ sizeof(struct ivtv_sg_element), PCI_DMA_TODEVICE);
+ ivtv_stream_sync_for_cpu(s);
+ }
+
+ /* allocate stream buffers. Initially all buffers are in q_free. */
+ for (i = 0; i < s->buffers; i++) {
+ struct ivtv_buffer *buf = kzalloc(sizeof(struct ivtv_buffer),
+ GFP_KERNEL|__GFP_NOWARN);
+
+ if (buf == NULL)
+ break;
+ buf->buf = kmalloc(s->buf_size + 256, GFP_KERNEL|__GFP_NOWARN);
+ if (buf->buf == NULL) {
+ kfree(buf);
+ break;
+ }
+ INIT_LIST_HEAD(&buf->list);
+ if (ivtv_might_use_dma(s)) {
+ buf->dma_handle = pci_map_single(s->itv->pdev,
+ buf->buf, s->buf_size + 256, s->dma);
+ ivtv_buf_sync_for_cpu(s, buf);
+ }
+ ivtv_enqueue(s, buf, &s->q_free);
+ }
+ if (i == s->buffers)
+ return 0;
+ IVTV_ERR("Couldn't allocate buffers for %s stream\n", s->name);
+ ivtv_stream_free(s);
+ return -ENOMEM;
+}
+
+void ivtv_stream_free(struct ivtv_stream *s)
+{
+ struct ivtv_buffer *buf;
+
+ /* move all buffers to q_free */
+ ivtv_flush_queues(s);
+
+ /* empty q_free */
+ while ((buf = ivtv_dequeue(s, &s->q_free))) {
+ if (ivtv_might_use_dma(s))
+ pci_unmap_single(s->itv->pdev, buf->dma_handle,
+ s->buf_size + 256, s->dma);
+ kfree(buf->buf);
+ kfree(buf);
+ }
+
+ /* Free SG Array/Lists */
+ if (s->sg_dma != NULL) {
+ if (s->sg_handle != IVTV_DMA_UNMAPPED) {
+ pci_unmap_single(s->itv->pdev, s->sg_handle,
+ sizeof(struct ivtv_sg_element), PCI_DMA_TODEVICE);
+ s->sg_handle = IVTV_DMA_UNMAPPED;
+ }
+ kfree(s->sg_pending);
+ kfree(s->sg_processing);
+ kfree(s->sg_dma);
+ s->sg_pending = NULL;
+ s->sg_processing = NULL;
+ s->sg_dma = NULL;
+ s->sg_pending_size = 0;
+ s->sg_processing_size = 0;
+ }
+}
Code Review / kvmfornfv.git / blobdiff