Merge branch 'linus' into x86/mm
[linux-2.6] / drivers / staging / usbip / vhci_rx.c
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 "usbip_common.h"
21 #include "vhci.h"
22
23
24 /* get URB from transmitted urb queue */
25 static struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev,
26                                             __u32 seqnum)
27 {
28         struct vhci_priv *priv, *tmp;
29         struct urb *urb = NULL;
30         int status;
31
32         spin_lock(&vdev->priv_lock);
33
34         list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) {
35                 if (priv->seqnum == seqnum) {
36                         urb = priv->urb;
37                         status = urb->status;
38
39                         dbg_vhci_rx("find urb %p vurb %p seqnum %u\n",
40                                     urb, priv, seqnum);
41
42                         /* TODO: fix logic here to improve indent situtation */
43                         if (status != -EINPROGRESS) {
44                                 if (status == -ENOENT ||
45                                      status == -ECONNRESET)
46                                         dev_info(&urb->dev->dev,
47                                                  "urb %p was unlinked "
48                                                  "%ssynchronuously.\n", urb,
49                                                  status == -ENOENT ? "" : "a");
50                                 else
51                                         dev_info(&urb->dev->dev,
52                                                  "urb %p may be in a error, "
53                                                  "status %d\n", urb, status);
54                         }
55
56                         list_del(&priv->list);
57                         kfree(priv);
58                         urb->hcpriv = NULL;
59
60                         break;
61                 }
62         }
63
64         spin_unlock(&vdev->priv_lock);
65
66         return urb;
67 }
68
69 static void vhci_recv_ret_submit(struct vhci_device *vdev,
70                                                 struct usbip_header *pdu)
71 {
72         struct usbip_device *ud = &vdev->ud;
73         struct urb *urb;
74
75
76         urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
77
78
79         if (!urb) {
80                 uerr("cannot find a urb of seqnum %u\n", pdu->base.seqnum);
81                 uinfo("max seqnum %d\n", atomic_read(&the_controller->seqnum));
82                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
83                 return;
84         }
85
86
87         /* unpack the pdu to a urb */
88         usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0);
89
90
91         /* recv transfer buffer */
92         if (usbip_recv_xbuff(ud, urb) < 0)
93                 return;
94
95
96         /* recv iso_packet_descriptor */
97         if (usbip_recv_iso(ud, urb) < 0)
98                 return;
99
100
101         if (dbg_flag_vhci_rx)
102                 usbip_dump_urb(urb);
103
104
105         dbg_vhci_rx("now giveback urb %p\n", urb);
106
107         spin_lock(&the_controller->lock);
108         usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
109         spin_unlock(&the_controller->lock);
110
111         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
112
113
114         dbg_vhci_rx("Leave\n");
115
116         return;
117 }
118
119
120 static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev,
121                 struct usbip_header *pdu)
122 {
123         struct vhci_unlink *unlink, *tmp;
124
125         spin_lock(&vdev->priv_lock);
126
127         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
128                 uinfo("unlink->seqnum %lu\n", unlink->seqnum);
129                 if (unlink->seqnum == pdu->base.seqnum) {
130                         dbg_vhci_rx("found pending unlink, %lu\n",
131                                                         unlink->seqnum);
132                         list_del(&unlink->list);
133
134                         spin_unlock(&vdev->priv_lock);
135                         return unlink;
136                 }
137         }
138
139         spin_unlock(&vdev->priv_lock);
140
141         return NULL;
142 }
143
144
145 static void vhci_recv_ret_unlink(struct vhci_device *vdev,
146                                                 struct usbip_header *pdu)
147 {
148         struct vhci_unlink *unlink;
149         struct urb *urb;
150
151         usbip_dump_header(pdu);
152
153         unlink = dequeue_pending_unlink(vdev, pdu);
154         if (!unlink) {
155                 uinfo("cannot find the pending unlink %u\n", pdu->base.seqnum);
156                 return;
157         }
158
159         urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
160         if (!urb) {
161                 /*
162                  * I get the result of a unlink request. But, it seems that I
163                  * already received the result of its submit result and gave
164                  * back the URB.
165                  */
166                 uinfo("the urb (seqnum %d) was already given backed\n",
167                                                         pdu->base.seqnum);
168         } else {
169                 dbg_vhci_rx("now giveback urb %p\n", urb);
170
171                 /* If unlink is succeed, status is -ECONNRESET */
172                 urb->status = pdu->u.ret_unlink.status;
173                 uinfo("%d\n", urb->status);
174
175                 spin_lock(&the_controller->lock);
176                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
177                 spin_unlock(&the_controller->lock);
178
179                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
180                                                                 urb->status);
181         }
182
183         kfree(unlink);
184
185         return;
186 }
187
188 /* recv a pdu */
189 static 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
196         dbg_vhci_rx("Enter\n");
197
198         memset(&pdu, 0, sizeof(pdu));
199
200
201         /* 1. receive a pdu header */
202         ret = usbip_xmit(0, ud->tcp_socket, (char *) &pdu, sizeof(pdu), 0);
203         if (ret != sizeof(pdu)) {
204                 uerr("receiving pdu failed! size is %d, should be %d\n",
205                                 ret, (unsigned int)sizeof(pdu));
206                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
207                 return;
208         }
209
210         usbip_header_correct_endian(&pdu, 0);
211
212         if (dbg_flag_vhci_rx)
213                 usbip_dump_header(&pdu);
214
215         switch (pdu.base.command) {
216         case USBIP_RET_SUBMIT:
217                 vhci_recv_ret_submit(vdev, &pdu);
218                 break;
219         case USBIP_RET_UNLINK:
220                 vhci_recv_ret_unlink(vdev, &pdu);
221                 break;
222         default:
223                 /* NOTREACHED */
224                 uerr("unknown pdu %u\n", pdu.base.command);
225                 usbip_dump_header(&pdu);
226                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
227         }
228 }
229
230
231 /*-------------------------------------------------------------------------*/
232
233 void vhci_rx_loop(struct usbip_task *ut)
234 {
235         struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_rx);
236
237
238         while (1) {
239                 if (signal_pending(current)) {
240                         dbg_vhci_rx("signal catched!\n");
241                         break;
242                 }
243
244
245                 if (usbip_event_happend(ud))
246                         break;
247
248                 vhci_rx_pdu(ud);
249         }
250 }
251