1/*
  2 * Copyright (C) 2003-2008 Takahiro Hirofuchi
  3 *
  4 * This is free software; you can redistribute it and/or modify
  5 * it under the terms of the GNU General Public License as published by
  6 * the Free Software Foundation; either version 2 of the License, or
  7 * (at your option) any later version.
  8 *
  9 * This is distributed in the hope that it will be useful,
 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 12 * GNU General Public License for more details.
 13 *
 14 * You should have received a copy of the GNU General Public License
 15 * along with this program; if not, write to the Free Software
 16 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
 17 * USA.
 18 */
 19
 20#include <linux/kthread.h>
 21#include <linux/slab.h>
 22
 23#include "usbip_common.h"
 24#include "vhci.h"
 25
 26static void setup_cmd_submit_pdu(struct usbip_header *pdup,  struct urb *urb)
 27{
 28	struct vhci_priv *priv = ((struct vhci_priv *)urb->hcpriv);
 29	struct vhci_device *vdev = priv->vdev;
 30
 31	usbip_dbg_vhci_tx("URB, local devnum %u, remote devid %u\n",
 32			  usb_pipedevice(urb->pipe), vdev->devid);
 33
 34	pdup->base.command   = USBIP_CMD_SUBMIT;
 35	pdup->base.seqnum    = priv->seqnum;
 36	pdup->base.devid     = vdev->devid;
 37	pdup->base.direction = usb_pipein(urb->pipe) ?
 38		USBIP_DIR_IN : USBIP_DIR_OUT;
 39	pdup->base.ep	     = usb_pipeendpoint(urb->pipe);
 40
 41	usbip_pack_pdu(pdup, urb, USBIP_CMD_SUBMIT, 1);
 42
 43	if (urb->setup_packet)
 44		memcpy(pdup->u.cmd_submit.setup, urb->setup_packet, 8);
 45}
 46
 47static struct vhci_priv *dequeue_from_priv_tx(struct vhci_device *vdev)
 48{
 49	struct vhci_priv *priv, *tmp;
 50	unsigned long flags;
 51
 52	spin_lock_irqsave(&vdev->priv_lock, flags);
 53
 54	list_for_each_entry_safe(priv, tmp, &vdev->priv_tx, list) {
 55		list_move_tail(&priv->list, &vdev->priv_rx);
 56		spin_unlock_irqrestore(&vdev->priv_lock, flags);
 57		return priv;
 58	}
 59
 60	spin_unlock_irqrestore(&vdev->priv_lock, flags);
 61
 62	return NULL;
 63}
 64
 65static int vhci_send_cmd_submit(struct vhci_device *vdev)
 66{
 67	struct vhci_priv *priv = NULL;
 68
 69	struct msghdr msg;
 70	struct kvec iov[3];
 71	size_t txsize;
 72
 73	size_t total_size = 0;
 74
 75	while ((priv = dequeue_from_priv_tx(vdev)) != NULL) {
 76		int ret;
 77		struct urb *urb = priv->urb;
 78		struct usbip_header pdu_header;
 79		struct usbip_iso_packet_descriptor *iso_buffer = NULL;
 80
 81		txsize = 0;
 82		memset(&pdu_header, 0, sizeof(pdu_header));
 83		memset(&msg, 0, sizeof(msg));
 84		memset(&iov, 0, sizeof(iov));
 85
 86		usbip_dbg_vhci_tx("setup txdata urb %p\n", urb);
 87
 88		/* 1. setup usbip_header */
 89		setup_cmd_submit_pdu(&pdu_header, urb);
 90		usbip_header_correct_endian(&pdu_header, 1);
 91
 92		iov[0].iov_base = &pdu_header;
 93		iov[0].iov_len  = sizeof(pdu_header);
 94		txsize += sizeof(pdu_header);
 95
 96		/* 2. setup transfer buffer */
 97		if (!usb_pipein(urb->pipe) && urb->transfer_buffer_length > 0) {
 98			iov[1].iov_base = urb->transfer_buffer;
 99			iov[1].iov_len  = urb->transfer_buffer_length;
100			txsize += urb->transfer_buffer_length;
101		}
102
103		/* 3. setup iso_packet_descriptor */
104		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
105			ssize_t len = 0;
106
107			iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
108			if (!iso_buffer) {
109				usbip_event_add(&vdev->ud,
110						SDEV_EVENT_ERROR_MALLOC);
111				return -1;
112			}
113
114			iov[2].iov_base = iso_buffer;
115			iov[2].iov_len  = len;
116			txsize += len;
117		}
118
119		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, iov, 3, txsize);
120		if (ret != txsize) {
121			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
122			       txsize);
123			kfree(iso_buffer);
124			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
125			return -1;
126		}
127
128		kfree(iso_buffer);
129		usbip_dbg_vhci_tx("send txdata\n");
130
131		total_size += txsize;
132	}
133
134	return total_size;
135}
136
137static struct vhci_unlink *dequeue_from_unlink_tx(struct vhci_device *vdev)
138{
139	struct vhci_unlink *unlink, *tmp;
140	unsigned long flags;
141
142	spin_lock_irqsave(&vdev->priv_lock, flags);
143
144	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
145		list_move_tail(&unlink->list, &vdev->unlink_rx);
146		spin_unlock_irqrestore(&vdev->priv_lock, flags);
147		return unlink;
148	}
149
150	spin_unlock_irqrestore(&vdev->priv_lock, flags);
151
152	return NULL;
153}
154
155static int vhci_send_cmd_unlink(struct vhci_device *vdev)
156{
157	struct vhci_unlink *unlink = NULL;
158
159	struct msghdr msg;
160	struct kvec iov[3];
161	size_t txsize;
162
163	size_t total_size = 0;
164
165	while ((unlink = dequeue_from_unlink_tx(vdev)) != NULL) {
166		int ret;
167		struct usbip_header pdu_header;
168
169		txsize = 0;
170		memset(&pdu_header, 0, sizeof(pdu_header));
171		memset(&msg, 0, sizeof(msg));
172		memset(&iov, 0, sizeof(iov));
173
174		usbip_dbg_vhci_tx("setup cmd unlink, %lu\n", unlink->seqnum);
175
176		/* 1. setup usbip_header */
177		pdu_header.base.command = USBIP_CMD_UNLINK;
178		pdu_header.base.seqnum  = unlink->seqnum;
179		pdu_header.base.devid	= vdev->devid;
180		pdu_header.base.ep	= 0;
181		pdu_header.u.cmd_unlink.seqnum = unlink->unlink_seqnum;
182
183		usbip_header_correct_endian(&pdu_header, 1);
184
185		iov[0].iov_base = &pdu_header;
186		iov[0].iov_len  = sizeof(pdu_header);
187		txsize += sizeof(pdu_header);
188
189		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, iov, 1, txsize);
190		if (ret != txsize) {
191			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
192			       txsize);
193			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
194			return -1;
195		}
196
197		usbip_dbg_vhci_tx("send txdata\n");
198
199		total_size += txsize;
200	}
201
202	return total_size;
203}
204
205int vhci_tx_loop(void *data)
206{
207	struct usbip_device *ud = data;
208	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
209
210	while (!kthread_should_stop()) {
211		if (vhci_send_cmd_submit(vdev) < 0)
212			break;
213
214		if (vhci_send_cmd_unlink(vdev) < 0)
215			break;
216
217		wait_event_interruptible(vdev->waitq_tx,
218					 (!list_empty(&vdev->priv_tx) ||
219					  !list_empty(&vdev->unlink_tx) ||
220					  kthread_should_stop()));
221
222		usbip_dbg_vhci_tx("pending urbs ?, now wake up\n");
223	}
224
225	return 0;
226}