lsi53c895a: check message length value is valid
[qemu/ar7.git] / hw / usb / combined-packet.c
blob01a7ed08488aa836897d661037ac917c2de2940f
1 /*
2 * QEMU USB packet combining code (for input pipelining)
4 * Copyright(c) 2012 Red Hat, Inc.
6 * Red Hat Authors:
7 * Hans de Goede <hdegoede@redhat.com>
9 * This library is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU Lesser General Public
11 * License as published by the Free Software Foundation; either
12 * version 2 of the License, or(at your option) any later version.
14 * This library is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, see <http://www.gnu.org/licenses/>.
22 #include "qemu/osdep.h"
23 #include "qemu/units.h"
24 #include "qemu-common.h"
25 #include "hw/usb.h"
26 #include "qemu/iov.h"
27 #include "trace.h"
29 static void usb_combined_packet_add(USBCombinedPacket *combined, USBPacket *p)
31 qemu_iovec_concat(&combined->iov, &p->iov, 0, p->iov.size);
32 QTAILQ_INSERT_TAIL(&combined->packets, p, combined_entry);
33 p->combined = combined;
36 /* Note will free combined when the last packet gets removed */
37 static void usb_combined_packet_remove(USBCombinedPacket *combined,
38 USBPacket *p)
40 assert(p->combined == combined);
41 p->combined = NULL;
42 QTAILQ_REMOVE(&combined->packets, p, combined_entry);
43 if (QTAILQ_EMPTY(&combined->packets)) {
44 qemu_iovec_destroy(&combined->iov);
45 g_free(combined);
49 /* Also handles completion of non combined packets for pipelined input eps */
50 void usb_combined_input_packet_complete(USBDevice *dev, USBPacket *p)
52 USBCombinedPacket *combined = p->combined;
53 USBEndpoint *ep = p->ep;
54 USBPacket *next;
55 int status, actual_length;
56 bool short_not_ok, done = false;
58 if (combined == NULL) {
59 usb_packet_complete_one(dev, p);
60 goto leave;
63 assert(combined->first == p && p == QTAILQ_FIRST(&combined->packets));
65 status = combined->first->status;
66 actual_length = combined->first->actual_length;
67 short_not_ok = QTAILQ_LAST(&combined->packets, packets_head)->short_not_ok;
69 QTAILQ_FOREACH_SAFE(p, &combined->packets, combined_entry, next) {
70 if (!done) {
71 /* Distribute data over uncombined packets */
72 if (actual_length >= p->iov.size) {
73 p->actual_length = p->iov.size;
74 } else {
75 /* Send short or error packet to complete the transfer */
76 p->actual_length = actual_length;
77 done = true;
79 /* Report status on the last packet */
80 if (done || next == NULL) {
81 p->status = status;
82 } else {
83 p->status = USB_RET_SUCCESS;
85 p->short_not_ok = short_not_ok;
86 /* Note will free combined when the last packet gets removed! */
87 usb_combined_packet_remove(combined, p);
88 usb_packet_complete_one(dev, p);
89 actual_length -= p->actual_length;
90 } else {
91 /* Remove any leftover packets from the queue */
92 p->status = USB_RET_REMOVE_FROM_QUEUE;
93 /* Note will free combined on the last packet! */
94 dev->port->ops->complete(dev->port, p);
97 /* Do not use combined here, it has been freed! */
98 leave:
99 /* Check if there are packets in the queue waiting for our completion */
100 usb_ep_combine_input_packets(ep);
103 /* May only be called for combined packets! */
104 void usb_combined_packet_cancel(USBDevice *dev, USBPacket *p)
106 USBCombinedPacket *combined = p->combined;
107 assert(combined != NULL);
108 USBPacket *first = p->combined->first;
110 /* Note will free combined on the last packet! */
111 usb_combined_packet_remove(combined, p);
112 if (p == first) {
113 usb_device_cancel_packet(dev, p);
118 * Large input transfers can get split into multiple input packets, this
119 * function recombines them, removing the short_not_ok checks which all but
120 * the last packet of such splits transfers have, thereby allowing input
121 * transfer pipelining (which we cannot do on short_not_ok transfers)
123 void usb_ep_combine_input_packets(USBEndpoint *ep)
125 USBPacket *p, *u, *next, *prev = NULL, *first = NULL;
126 USBPort *port = ep->dev->port;
127 int totalsize;
129 assert(ep->pipeline);
130 assert(ep->pid == USB_TOKEN_IN);
132 QTAILQ_FOREACH_SAFE(p, &ep->queue, queue, next) {
133 /* Empty the queue on a halt */
134 if (ep->halted) {
135 p->status = USB_RET_REMOVE_FROM_QUEUE;
136 port->ops->complete(port, p);
137 continue;
140 /* Skip packets already submitted to the device */
141 if (p->state == USB_PACKET_ASYNC) {
142 prev = p;
143 continue;
145 usb_packet_check_state(p, USB_PACKET_QUEUED);
148 * If the previous (combined) packet has the short_not_ok flag set
149 * stop, as we must not submit packets to the device after a transfer
150 * ending with short_not_ok packet.
152 if (prev && prev->short_not_ok) {
153 break;
156 if (first) {
157 if (first->combined == NULL) {
158 USBCombinedPacket *combined = g_new0(USBCombinedPacket, 1);
160 combined->first = first;
161 QTAILQ_INIT(&combined->packets);
162 qemu_iovec_init(&combined->iov, 2);
163 usb_combined_packet_add(combined, first);
165 usb_combined_packet_add(first->combined, p);
166 } else {
167 first = p;
170 /* Is this packet the last one of a (combined) transfer? */
171 totalsize = (p->combined) ? p->combined->iov.size : p->iov.size;
172 if ((p->iov.size % ep->max_packet_size) != 0 || !p->short_not_ok ||
173 next == NULL ||
174 /* Work around for Linux usbfs bulk splitting + migration */
175 (totalsize == (16 * KiB - 36) && p->int_req)) {
176 usb_device_handle_data(ep->dev, first);
177 assert(first->status == USB_RET_ASYNC);
178 if (first->combined) {
179 QTAILQ_FOREACH(u, &first->combined->packets, combined_entry) {
180 usb_packet_set_state(u, USB_PACKET_ASYNC);
182 } else {
183 usb_packet_set_state(first, USB_PACKET_ASYNC);
185 first = NULL;
186 prev = p;