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 
setup_cmd_submit_pdu(struct usbip_header * pdup,struct urb * urb)13 static 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 
dequeue_from_priv_tx(struct vhci_device * vdev)34 static 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 
vhci_send_cmd_submit(struct vhci_device * vdev)52 static 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 
161 err_tx:
162 	kfree(iso_buffer);
163 err_iso_buffer:
164 	kfree(iov);
165 
166 	return err;
167 }
168 
dequeue_from_unlink_tx(struct vhci_device * vdev)169 static 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 
vhci_send_cmd_unlink(struct vhci_device * vdev)187 static 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 
vhci_tx_loop(void * data)235 int 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 }
257