1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
  4 */
  5
  6#include <linux/kthread.h>
  7#include <linux/slab.h>
  8
  9#include "usbip_common.h"
 10#include "vhci.h"
 11
 12static void setup_cmd_submit_pdu(struct usbip_header *pdup,  struct urb *urb)
 13{
 14	struct vhci_priv *priv = ((struct vhci_priv *)urb->hcpriv);
 15	struct vhci_device *vdev = priv->vdev;
 16
 17	usbip_dbg_vhci_tx("URB, local devnum %u, remote devid %u\n",
 18			  usb_pipedevice(urb->pipe), vdev->devid);
 19
 20	pdup->base.command   = USBIP_CMD_SUBMIT;
 21	pdup->base.seqnum    = priv->seqnum;
 22	pdup->base.devid     = vdev->devid;
 23	pdup->base.direction = usb_pipein(urb->pipe) ?
 24		USBIP_DIR_IN : USBIP_DIR_OUT;
 25	pdup->base.ep	     = usb_pipeendpoint(urb->pipe);
 26
 27	usbip_pack_pdu(pdup, urb, USBIP_CMD_SUBMIT, 1);
 28
 29	if (urb->setup_packet)
 30		memcpy(pdup->u.cmd_submit.setup, urb->setup_packet, 8);
 31}
 32
 33static struct vhci_priv *dequeue_from_priv_tx(struct vhci_device *vdev)
 34{
 35	struct vhci_priv *priv, *tmp;
 36	unsigned long flags;
 37
 38	spin_lock_irqsave(&vdev->priv_lock, flags);
 39
 40	list_for_each_entry_safe(priv, tmp, &vdev->priv_tx, list) {
 41		list_move_tail(&priv->list, &vdev->priv_rx);
 42		spin_unlock_irqrestore(&vdev->priv_lock, flags);
 43		return priv;
 44	}
 45
 46	spin_unlock_irqrestore(&vdev->priv_lock, flags);
 47
 48	return NULL;
 49}
 50
 51static int vhci_send_cmd_submit(struct vhci_device *vdev)
 52{
 53	struct vhci_priv *priv = NULL;
 54
 55	struct msghdr msg;
 56	struct kvec iov[3];
 57	size_t txsize;
 58
 59	size_t total_size = 0;
 60
 61	while ((priv = dequeue_from_priv_tx(vdev)) != NULL) {
 62		int ret;
 63		struct urb *urb = priv->urb;
 64		struct usbip_header pdu_header;
 65		struct usbip_iso_packet_descriptor *iso_buffer = NULL;
 66
 67		txsize = 0;
 68		memset(&pdu_header, 0, sizeof(pdu_header));
 69		memset(&msg, 0, sizeof(msg));
 70		memset(&iov, 0, sizeof(iov));
 71
 72		usbip_dbg_vhci_tx("setup txdata urb seqnum %lu\n",
 73				  priv->seqnum);
 74
 75		/* 1. setup usbip_header */
 76		setup_cmd_submit_pdu(&pdu_header, urb);
 77		usbip_header_correct_endian(&pdu_header, 1);
 78
 79		iov[0].iov_base = &pdu_header;
 80		iov[0].iov_len  = sizeof(pdu_header);
 81		txsize += sizeof(pdu_header);
 82
 83		/* 2. setup transfer buffer */
 84		if (!usb_pipein(urb->pipe) && urb->transfer_buffer_length > 0) {
 85			iov[1].iov_base = urb->transfer_buffer;
 86			iov[1].iov_len  = urb->transfer_buffer_length;
 87			txsize += urb->transfer_buffer_length;
 88		}
 89
 90		/* 3. setup iso_packet_descriptor */
 91		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
 92			ssize_t len = 0;
 93
 94			iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
 95			if (!iso_buffer) {
 96				usbip_event_add(&vdev->ud,
 97						SDEV_EVENT_ERROR_MALLOC);
 98				return -1;
 99			}
100
101			iov[2].iov_base = iso_buffer;
102			iov[2].iov_len  = len;
103			txsize += len;
104		}
105
106		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, iov, 3, txsize);
107		if (ret != txsize) {
108			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
109			       txsize);
110			kfree(iso_buffer);
111			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
112			return -1;
113		}
114
115		kfree(iso_buffer);
116		usbip_dbg_vhci_tx("send txdata\n");
117
118		total_size += txsize;
119	}
120
121	return total_size;
122}
123
124static struct vhci_unlink *dequeue_from_unlink_tx(struct vhci_device *vdev)
125{
126	struct vhci_unlink *unlink, *tmp;
127	unsigned long flags;
128
129	spin_lock_irqsave(&vdev->priv_lock, flags);
130
131	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
132		list_move_tail(&unlink->list, &vdev->unlink_rx);
133		spin_unlock_irqrestore(&vdev->priv_lock, flags);
134		return unlink;
135	}
136
137	spin_unlock_irqrestore(&vdev->priv_lock, flags);
138
139	return NULL;
140}
141
142static int vhci_send_cmd_unlink(struct vhci_device *vdev)
143{
144	struct vhci_unlink *unlink = NULL;
145
146	struct msghdr msg;
147	struct kvec iov[3];
148	size_t txsize;
149
150	size_t total_size = 0;
151
152	while ((unlink = dequeue_from_unlink_tx(vdev)) != NULL) {
153		int ret;
154		struct usbip_header pdu_header;
155
156		txsize = 0;
157		memset(&pdu_header, 0, sizeof(pdu_header));
158		memset(&msg, 0, sizeof(msg));
159		memset(&iov, 0, sizeof(iov));
160
161		usbip_dbg_vhci_tx("setup cmd unlink, %lu\n", unlink->seqnum);
162
163		/* 1. setup usbip_header */
164		pdu_header.base.command = USBIP_CMD_UNLINK;
165		pdu_header.base.seqnum  = unlink->seqnum;
166		pdu_header.base.devid	= vdev->devid;
167		pdu_header.base.ep	= 0;
168		pdu_header.u.cmd_unlink.seqnum = unlink->unlink_seqnum;
169
170		usbip_header_correct_endian(&pdu_header, 1);
171
172		iov[0].iov_base = &pdu_header;
173		iov[0].iov_len  = sizeof(pdu_header);
174		txsize += sizeof(pdu_header);
175
176		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, iov, 1, txsize);
177		if (ret != txsize) {
178			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
179			       txsize);
180			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
181			return -1;
182		}
183
184		usbip_dbg_vhci_tx("send txdata\n");
185
186		total_size += txsize;
187	}
188
189	return total_size;
190}
191
192int vhci_tx_loop(void *data)
193{
194	struct usbip_device *ud = data;
195	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
196
197	while (!kthread_should_stop()) {
198		if (vhci_send_cmd_submit(vdev) < 0)
199			break;
200
201		if (vhci_send_cmd_unlink(vdev) < 0)
202			break;
203
204		wait_event_interruptible(vdev->waitq_tx,
205					 (!list_empty(&vdev->priv_tx) ||
206					  !list_empty(&vdev->unlink_tx) ||
207					  kthread_should_stop()));
208
209		usbip_dbg_vhci_tx("pending urbs ?, now wake up\n");
210	}
211
212	return 0;
213}