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5
6#include <linux/kthread.h>
7#include <linux/slab.h>
8
9#include "usbip_common.h"
10#include "vhci.h"
11
12
13struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum)
14{
15 struct vhci_priv *priv, *tmp;
16 struct urb *urb = NULL;
17 int status;
18
19 list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) {
20 if (priv->seqnum != seqnum)
21 continue;
22
23 urb = priv->urb;
24 status = urb->status;
25
26 usbip_dbg_vhci_rx("find urb seqnum %u\n", seqnum);
27
28 switch (status) {
29 case -ENOENT:
30
31 case -ECONNRESET:
32 dev_dbg(&urb->dev->dev,
33 "urb seq# %u was unlinked %ssynchronously\n",
34 seqnum, status == -ENOENT ? "" : "a");
35 break;
36 case -EINPROGRESS:
37
38 break;
39 default:
40 dev_dbg(&urb->dev->dev,
41 "urb seq# %u may be in a error, status %d\n",
42 seqnum, status);
43 }
44
45 list_del(&priv->list);
46 kfree(priv);
47 urb->hcpriv = NULL;
48
49 break;
50 }
51
52 return urb;
53}
54
55static void vhci_recv_ret_submit(struct vhci_device *vdev,
56 struct usbip_header *pdu)
57{
58 struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev);
59 struct vhci *vhci = vhci_hcd->vhci;
60 struct usbip_device *ud = &vdev->ud;
61 struct urb *urb;
62 unsigned long flags;
63
64 spin_lock_irqsave(&vdev->priv_lock, flags);
65 urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
66 spin_unlock_irqrestore(&vdev->priv_lock, flags);
67
68 if (!urb) {
69 pr_err("cannot find a urb of seqnum %u max seqnum %d\n",
70 pdu->base.seqnum,
71 atomic_read(&vhci_hcd->seqnum));
72 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
73 return;
74 }
75
76
77 usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0);
78
79
80 if (usbip_recv_xbuff(ud, urb) < 0)
81 return;
82
83
84 if (usbip_recv_iso(ud, urb) < 0)
85 return;
86
87
88 usbip_pad_iso(ud, urb);
89
90 if (usbip_dbg_flag_vhci_rx)
91 usbip_dump_urb(urb);
92
93 usbip_dbg_vhci_rx("now giveback urb %u\n", pdu->base.seqnum);
94
95 spin_lock_irqsave(&vhci->lock, flags);
96 usb_hcd_unlink_urb_from_ep(vhci_hcd_to_hcd(vhci_hcd), urb);
97 spin_unlock_irqrestore(&vhci->lock, flags);
98
99 usb_hcd_giveback_urb(vhci_hcd_to_hcd(vhci_hcd), urb, urb->status);
100
101 usbip_dbg_vhci_rx("Leave\n");
102}
103
104static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev,
105 struct usbip_header *pdu)
106{
107 struct vhci_unlink *unlink, *tmp;
108 unsigned long flags;
109
110 spin_lock_irqsave(&vdev->priv_lock, flags);
111
112 list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
113 pr_info("unlink->seqnum %lu\n", unlink->seqnum);
114 if (unlink->seqnum == pdu->base.seqnum) {
115 usbip_dbg_vhci_rx("found pending unlink, %lu\n",
116 unlink->seqnum);
117 list_del(&unlink->list);
118
119 spin_unlock_irqrestore(&vdev->priv_lock, flags);
120 return unlink;
121 }
122 }
123
124 spin_unlock_irqrestore(&vdev->priv_lock, flags);
125
126 return NULL;
127}
128
129static void vhci_recv_ret_unlink(struct vhci_device *vdev,
130 struct usbip_header *pdu)
131{
132 struct vhci_hcd *vhci_hcd = vdev_to_vhci_hcd(vdev);
133 struct vhci *vhci = vhci_hcd->vhci;
134 struct vhci_unlink *unlink;
135 struct urb *urb;
136 unsigned long flags;
137
138 usbip_dump_header(pdu);
139
140 unlink = dequeue_pending_unlink(vdev, pdu);
141 if (!unlink) {
142 pr_info("cannot find the pending unlink %u\n",
143 pdu->base.seqnum);
144 return;
145 }
146
147 spin_lock_irqsave(&vdev->priv_lock, flags);
148 urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
149 spin_unlock_irqrestore(&vdev->priv_lock, flags);
150
151 if (!urb) {
152
153
154
155
156
157 pr_info("the urb (seqnum %d) was already given back\n",
158 pdu->base.seqnum);
159 } else {
160 usbip_dbg_vhci_rx("now giveback urb %d\n", pdu->base.seqnum);
161
162
163 urb->status = pdu->u.ret_unlink.status;
164 pr_info("urb->status %d\n", urb->status);
165
166 spin_lock_irqsave(&vhci->lock, flags);
167 usb_hcd_unlink_urb_from_ep(vhci_hcd_to_hcd(vhci_hcd), urb);
168 spin_unlock_irqrestore(&vhci->lock, flags);
169
170 usb_hcd_giveback_urb(vhci_hcd_to_hcd(vhci_hcd), urb, urb->status);
171 }
172
173 kfree(unlink);
174}
175
176static int vhci_priv_tx_empty(struct vhci_device *vdev)
177{
178 int empty = 0;
179 unsigned long flags;
180
181 spin_lock_irqsave(&vdev->priv_lock, flags);
182 empty = list_empty(&vdev->priv_rx);
183 spin_unlock_irqrestore(&vdev->priv_lock, flags);
184
185 return empty;
186}
187
188
189static void vhci_rx_pdu(struct usbip_device *ud)
190{
191 int ret;
192 struct usbip_header pdu;
193 struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
194
195 usbip_dbg_vhci_rx("Enter\n");
196
197 memset(&pdu, 0, sizeof(pdu));
198
199
200 ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu));
201 if (ret < 0) {
202 if (ret == -ECONNRESET)
203 pr_info("connection reset by peer\n");
204 else if (ret == -EAGAIN) {
205
206 if (vhci_priv_tx_empty(vdev))
207 return;
208 pr_info("connection timed out with pending urbs\n");
209 } else if (ret != -ERESTARTSYS)
210 pr_info("xmit failed %d\n", ret);
211
212 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
213 return;
214 }
215 if (ret == 0) {
216 pr_info("connection closed");
217 usbip_event_add(ud, VDEV_EVENT_DOWN);
218 return;
219 }
220 if (ret != sizeof(pdu)) {
221 pr_err("received pdu size is %d, should be %d\n", ret,
222 (unsigned int)sizeof(pdu));
223 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
224 return;
225 }
226
227 usbip_header_correct_endian(&pdu, 0);
228
229 if (usbip_dbg_flag_vhci_rx)
230 usbip_dump_header(&pdu);
231
232 switch (pdu.base.command) {
233 case USBIP_RET_SUBMIT:
234 vhci_recv_ret_submit(vdev, &pdu);
235 break;
236 case USBIP_RET_UNLINK:
237 vhci_recv_ret_unlink(vdev, &pdu);
238 break;
239 default:
240
241 pr_err("unknown pdu %u\n", pdu.base.command);
242 usbip_dump_header(&pdu);
243 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
244 break;
245 }
246}
247
248int vhci_rx_loop(void *data)
249{
250 struct usbip_device *ud = data;
251
252 while (!kthread_should_stop()) {
253 if (usbip_event_happened(ud))
254 break;
255
256 vhci_rx_pdu(ud);
257 }
258
259 return 0;
260}
261
