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#include <linux/scatterlist.h>
  9
 10#include "usbip_common.h"
 11#include "vhci.h"
 12
 13static void setup_cmd_submit_pdu(struct usbip_header *pdup,  struct urb *urb)
 14{
 15	struct vhci_priv *priv = ((struct vhci_priv *)urb->hcpriv);
 16	struct vhci_device *vdev = priv->vdev;
 17
 18	usbip_dbg_vhci_tx("URB, local devnum %u, remote devid %u\n",
 19			  usb_pipedevice(urb->pipe), vdev->devid);
 20
 21	pdup->base.command   = USBIP_CMD_SUBMIT;
 22	pdup->base.seqnum    = priv->seqnum;
 23	pdup->base.devid     = vdev->devid;
 24	pdup->base.direction = usb_pipein(urb->pipe) ?
 25		USBIP_DIR_IN : USBIP_DIR_OUT;
 26	pdup->base.ep	     = usb_pipeendpoint(urb->pipe);
 27
 28	usbip_pack_pdu(pdup, urb, USBIP_CMD_SUBMIT, 1);
 29
 30	if (urb->setup_packet)
 31		memcpy(pdup->u.cmd_submit.setup, urb->setup_packet, 8);
 32}
 33
 34static struct vhci_priv *dequeue_from_priv_tx(struct vhci_device *vdev)
 35{
 36	struct vhci_priv *priv, *tmp;
 37	unsigned long flags;
 38
 39	spin_lock_irqsave(&vdev->priv_lock, flags);
 40
 41	list_for_each_entry_safe(priv, tmp, &vdev->priv_tx, list) {
 42		list_move_tail(&priv->list, &vdev->priv_rx);
 43		spin_unlock_irqrestore(&vdev->priv_lock, flags);
 44		return priv;
 45	}
 46
 47	spin_unlock_irqrestore(&vdev->priv_lock, flags);
 48
 49	return NULL;
 50}
 51
 52static int vhci_send_cmd_submit(struct vhci_device *vdev)
 53{
 54	struct usbip_iso_packet_descriptor *iso_buffer = NULL;
 55	struct vhci_priv *priv = NULL;
 56	struct scatterlist *sg;
 57
 58	struct msghdr msg;
 59	struct kvec *iov;
 60	size_t txsize;
 61
 62	size_t total_size = 0;
 63	int iovnum;
 64	int err = -ENOMEM;
 65	int i;
 66
 67	while ((priv = dequeue_from_priv_tx(vdev)) != NULL) {
 68		int ret;
 69		struct urb *urb = priv->urb;
 70		struct usbip_header pdu_header;
 71
 72		txsize = 0;
 73		memset(&pdu_header, 0, sizeof(pdu_header));
 74		memset(&msg, 0, sizeof(msg));
 75		memset(&iov, 0, sizeof(iov));
 76
 77		usbip_dbg_vhci_tx("setup txdata urb seqnum %lu\n",
 78				  priv->seqnum);
 79
 80		if (urb->num_sgs && usb_pipeout(urb->pipe))
 81			iovnum = 2 + urb->num_sgs;
 82		else
 83			iovnum = 3;
 84
 85		iov = kcalloc(iovnum, sizeof(*iov), GFP_KERNEL);
 86		if (!iov) {
 87			usbip_event_add(&vdev->ud, SDEV_EVENT_ERROR_MALLOC);
 88			return -ENOMEM;
 89		}
 90
 91		if (urb->num_sgs)
 92			urb->transfer_flags |= URB_DMA_MAP_SG;
 93
 94		/* 1. setup usbip_header */
 95		setup_cmd_submit_pdu(&pdu_header, urb);
 96		usbip_header_correct_endian(&pdu_header, 1);
 97		iovnum = 0;
 98
 99		iov[iovnum].iov_base = &pdu_header;
100		iov[iovnum].iov_len  = sizeof(pdu_header);
101		txsize += sizeof(pdu_header);
102		iovnum++;
103
104		/* 2. setup transfer buffer */
105		if (!usb_pipein(urb->pipe) && urb->transfer_buffer_length > 0) {
106			if (urb->num_sgs &&
107				      !usb_endpoint_xfer_isoc(&urb->ep->desc)) {
108				for_each_sg(urb->sg, sg, urb->num_sgs, i) {
109					iov[iovnum].iov_base = sg_virt(sg);
110					iov[iovnum].iov_len = sg->length;
111					iovnum++;
112				}
113			} else {
114				iov[iovnum].iov_base = urb->transfer_buffer;
115				iov[iovnum].iov_len  =
116						urb->transfer_buffer_length;
117				iovnum++;
118			}
119			txsize += urb->transfer_buffer_length;
120		}
121
122		/* 3. setup iso_packet_descriptor */
123		if (usb_pipetype(urb->pipe) == PIPE_ISOCHRONOUS) {
124			ssize_t len = 0;
125
126			iso_buffer = usbip_alloc_iso_desc_pdu(urb, &len);
127			if (!iso_buffer) {
128				usbip_event_add(&vdev->ud,
129						SDEV_EVENT_ERROR_MALLOC);
130				goto err_iso_buffer;
131			}
132
133			iov[iovnum].iov_base = iso_buffer;
134			iov[iovnum].iov_len  = len;
135			iovnum++;
136			txsize += len;
137		}
138
139		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, iov, iovnum,
140				     txsize);
141		if (ret != txsize) {
142			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
143			       txsize);
144			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
145			err = -EPIPE;
146			goto err_tx;
147		}
148
149		kfree(iov);
150		/* This is only for isochronous case */
151		kfree(iso_buffer);
152		iso_buffer = NULL;
153
154		usbip_dbg_vhci_tx("send txdata\n");
155
156		total_size += txsize;
157	}
158
159	return total_size;
160
161err_tx:
162	kfree(iso_buffer);
163err_iso_buffer:
164	kfree(iov);
165
166	return err;
167}
168
169static struct vhci_unlink *dequeue_from_unlink_tx(struct vhci_device *vdev)
170{
171	struct vhci_unlink *unlink, *tmp;
172	unsigned long flags;
173
174	spin_lock_irqsave(&vdev->priv_lock, flags);
175
176	list_for_each_entry_safe(unlink, tmp, &vdev->unlink_tx, list) {
177		list_move_tail(&unlink->list, &vdev->unlink_rx);
178		spin_unlock_irqrestore(&vdev->priv_lock, flags);
179		return unlink;
180	}
181
182	spin_unlock_irqrestore(&vdev->priv_lock, flags);
183
184	return NULL;
185}
186
187static int vhci_send_cmd_unlink(struct vhci_device *vdev)
188{
189	struct vhci_unlink *unlink = NULL;
190
191	struct msghdr msg;
192	struct kvec iov;
193	size_t txsize;
194	size_t total_size = 0;
195
196	while ((unlink = dequeue_from_unlink_tx(vdev)) != NULL) {
197		int ret;
198		struct usbip_header pdu_header;
199
200		memset(&pdu_header, 0, sizeof(pdu_header));
201		memset(&msg, 0, sizeof(msg));
202		memset(&iov, 0, sizeof(iov));
203
204		usbip_dbg_vhci_tx("setup cmd unlink, %lu\n", unlink->seqnum);
205
206		/* 1. setup usbip_header */
207		pdu_header.base.command = USBIP_CMD_UNLINK;
208		pdu_header.base.seqnum  = unlink->seqnum;
209		pdu_header.base.devid	= vdev->devid;
210		pdu_header.base.ep	= 0;
211		pdu_header.u.cmd_unlink.seqnum = unlink->unlink_seqnum;
212
213		usbip_header_correct_endian(&pdu_header, 1);
214
215		iov.iov_base = &pdu_header;
216		iov.iov_len  = sizeof(pdu_header);
217		txsize = sizeof(pdu_header);
218
219		ret = kernel_sendmsg(vdev->ud.tcp_socket, &msg, &iov, 1, txsize);
220		if (ret != txsize) {
221			pr_err("sendmsg failed!, ret=%d for %zd\n", ret,
222			       txsize);
223			usbip_event_add(&vdev->ud, VDEV_EVENT_ERROR_TCP);
224			return -1;
225		}
226
227		usbip_dbg_vhci_tx("send txdata\n");
228
229		total_size += txsize;
230	}
231
232	return total_size;
233}
234
235int vhci_tx_loop(void *data)
236{
237	struct usbip_device *ud = data;
238	struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
239
240	while (!kthread_should_stop()) {
241		if (vhci_send_cmd_submit(vdev) < 0)
242			break;
243
244		if (vhci_send_cmd_unlink(vdev) < 0)
245			break;
246
247		wait_event_interruptible(vdev->waitq_tx,
248					 (!list_empty(&vdev->priv_tx) ||
249					  !list_empty(&vdev->unlink_tx) ||
250					  kthread_should_stop()));
251
252		usbip_dbg_vhci_tx("pending urbs ?, now wake up\n");
253	}
254
255	return 0;
256}