--- /dev/null
+/*
+ * QEMU USB packet combining code (for input pipelining)
+ *
+ * Copyright(c) 2012 Red Hat, Inc.
+ *
+ * Red Hat Authors:
+ * Hans de Goede <hdegoede@redhat.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or(at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include "qemu-common.h"
+#include "hw/usb.h"
+#include "qemu/iov.h"
+#include "trace.h"
+
+static void usb_combined_packet_add(USBCombinedPacket *combined, USBPacket *p)
+{
+ qemu_iovec_concat(&combined->iov, &p->iov, 0, p->iov.size);
+ QTAILQ_INSERT_TAIL(&combined->packets, p, combined_entry);
+ p->combined = combined;
+}
+
+/* Note will free combined when the last packet gets removed */
+static void usb_combined_packet_remove(USBCombinedPacket *combined,
+ USBPacket *p)
+{
+ assert(p->combined == combined);
+ p->combined = NULL;
+ QTAILQ_REMOVE(&combined->packets, p, combined_entry);
+ if (QTAILQ_EMPTY(&combined->packets)) {
+ qemu_iovec_destroy(&combined->iov);
+ g_free(combined);
+ }
+}
+
+/* Also handles completion of non combined packets for pipelined input eps */
+void usb_combined_input_packet_complete(USBDevice *dev, USBPacket *p)
+{
+ USBCombinedPacket *combined = p->combined;
+ USBEndpoint *ep = p->ep;
+ USBPacket *next;
+ int status, actual_length;
+ bool short_not_ok, done = false;
+
+ if (combined == NULL) {
+ usb_packet_complete_one(dev, p);
+ goto leave;
+ }
+
+ assert(combined->first == p && p == QTAILQ_FIRST(&combined->packets));
+
+ status = combined->first->status;
+ actual_length = combined->first->actual_length;
+ short_not_ok = QTAILQ_LAST(&combined->packets, packets_head)->short_not_ok;
+
+ QTAILQ_FOREACH_SAFE(p, &combined->packets, combined_entry, next) {
+ if (!done) {
+ /* Distribute data over uncombined packets */
+ if (actual_length >= p->iov.size) {
+ p->actual_length = p->iov.size;
+ } else {
+ /* Send short or error packet to complete the transfer */
+ p->actual_length = actual_length;
+ done = true;
+ }
+ /* Report status on the last packet */
+ if (done || next == NULL) {
+ p->status = status;
+ } else {
+ p->status = USB_RET_SUCCESS;
+ }
+ p->short_not_ok = short_not_ok;
+ /* Note will free combined when the last packet gets removed! */
+ usb_combined_packet_remove(combined, p);
+ usb_packet_complete_one(dev, p);
+ actual_length -= p->actual_length;
+ } else {
+ /* Remove any leftover packets from the queue */
+ p->status = USB_RET_REMOVE_FROM_QUEUE;
+ /* Note will free combined on the last packet! */
+ dev->port->ops->complete(dev->port, p);
+ }
+ }
+ /* Do not use combined here, it has been freed! */
+leave:
+ /* Check if there are packets in the queue waiting for our completion */
+ usb_ep_combine_input_packets(ep);
+}
+
+/* May only be called for combined packets! */
+void usb_combined_packet_cancel(USBDevice *dev, USBPacket *p)
+{
+ USBCombinedPacket *combined = p->combined;
+ assert(combined != NULL);
+ USBPacket *first = p->combined->first;
+
+ /* Note will free combined on the last packet! */
+ usb_combined_packet_remove(combined, p);
+ if (p == first) {
+ usb_device_cancel_packet(dev, p);
+ }
+}
+
+/*
+ * Large input transfers can get split into multiple input packets, this
+ * function recombines them, removing the short_not_ok checks which all but
+ * the last packet of such splits transfers have, thereby allowing input
+ * transfer pipelining (which we cannot do on short_not_ok transfers)
+ */
+void usb_ep_combine_input_packets(USBEndpoint *ep)
+{
+ USBPacket *p, *u, *next, *prev = NULL, *first = NULL;
+ USBPort *port = ep->dev->port;
+ int totalsize;
+
+ assert(ep->pipeline);
+ assert(ep->pid == USB_TOKEN_IN);
+
+ QTAILQ_FOREACH_SAFE(p, &ep->queue, queue, next) {
+ /* Empty the queue on a halt */
+ if (ep->halted) {
+ p->status = USB_RET_REMOVE_FROM_QUEUE;
+ port->ops->complete(port, p);
+ continue;
+ }
+
+ /* Skip packets already submitted to the device */
+ if (p->state == USB_PACKET_ASYNC) {
+ prev = p;
+ continue;
+ }
+ usb_packet_check_state(p, USB_PACKET_QUEUED);
+
+ /*
+ * If the previous (combined) packet has the short_not_ok flag set
+ * stop, as we must not submit packets to the device after a transfer
+ * ending with short_not_ok packet.
+ */
+ if (prev && prev->short_not_ok) {
+ break;
+ }
+
+ if (first) {
+ if (first->combined == NULL) {
+ USBCombinedPacket *combined = g_new0(USBCombinedPacket, 1);
+
+ combined->first = first;
+ QTAILQ_INIT(&combined->packets);
+ qemu_iovec_init(&combined->iov, 2);
+ usb_combined_packet_add(combined, first);
+ }
+ usb_combined_packet_add(first->combined, p);
+ } else {
+ first = p;
+ }
+
+ /* Is this packet the last one of a (combined) transfer? */
+ totalsize = (p->combined) ? p->combined->iov.size : p->iov.size;
+ if ((p->iov.size % ep->max_packet_size) != 0 || !p->short_not_ok ||
+ next == NULL ||
+ /* Work around for Linux usbfs bulk splitting + migration */
+ (totalsize == 16348 && p->int_req)) {
+ usb_device_handle_data(ep->dev, first);
+ assert(first->status == USB_RET_ASYNC);
+ if (first->combined) {
+ QTAILQ_FOREACH(u, &first->combined->packets, combined_entry) {
+ usb_packet_set_state(u, USB_PACKET_ASYNC);
+ }
+ } else {
+ usb_packet_set_state(first, USB_PACKET_ASYNC);
+ }
+ first = NULL;
+ prev = p;
+ }
+ }
+}
Code Review / kvmfornfv.git / blobdiff