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 <linux/kthread.h> 21#include <linux/slab.h> 22 23#include "usbip_common.h" 24#include "vhci.h" 25 26/* get URB from transmitted urb queue. caller must hold vdev->priv_lock */ 27struct urb *pickup_urb_and_free_priv(struct vhci_device *vdev, __u32 seqnum) 28{ 29 struct vhci_priv *priv, *tmp; 30 struct urb *urb = NULL; 31 int status; 32 33 list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) { 34 if (priv->seqnum == seqnum) { 35 urb = priv->urb; 36 status = urb->status; 37 38 usbip_dbg_vhci_rx("find urb %p vurb %p seqnum %u\n", 39 urb, priv, seqnum); 40 41 /* TODO: fix logic here to improve indent situtation */ 42 if (status != -EINPROGRESS) { 43 if (status == -ENOENT || 44 status == -ECONNRESET) 45 dev_info(&urb->dev->dev, 46 "urb %p was unlinked " 47 "%ssynchronuously.\n", urb, 48 status == -ENOENT ? "" : "a"); 49 else 50 dev_info(&urb->dev->dev, 51 "urb %p may be in a error, " 52 "status %d\n", urb, status); 53 } 54 55 list_del(&priv->list); 56 kfree(priv); 57 urb->hcpriv = NULL; 58 59 break; 60 } 61 } 62 63 return urb; 64} 65 66static void vhci_recv_ret_submit(struct vhci_device *vdev, 67 struct usbip_header *pdu) 68{ 69 struct usbip_device *ud = &vdev->ud; 70 struct urb *urb; 71 unsigned long flags; 72 73 spin_lock(&vdev->priv_lock); 74 urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum); 75 spin_unlock(&vdev->priv_lock); 76 77 if (!urb) { 78 pr_err("cannot find a urb of seqnum %u\n", pdu->base.seqnum); 79 pr_info("max seqnum %d\n", 80 atomic_read(&the_controller->seqnum)); 81 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); 82 return; 83 } 84 85 /* unpack the pdu to a urb */ 86 usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0); 87 88 /* recv transfer buffer */ 89 if (usbip_recv_xbuff(ud, urb) < 0) 90 return; 91 92 /* recv iso_packet_descriptor */ 93 if (usbip_recv_iso(ud, urb) < 0) 94 return; 95 96 /* restore the padding in iso packets */ 97 usbip_pad_iso(ud, urb); 98 99 if (usbip_dbg_flag_vhci_rx) 100 usbip_dump_urb(urb); 101 102 usbip_dbg_vhci_rx("now giveback urb %p\n", urb); 103 104 spin_lock_irqsave(&the_controller->lock, flags); 105 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb); 106 spin_unlock_irqrestore(&the_controller->lock, flags); 107 108 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status); 109 110 usbip_dbg_vhci_rx("Leave\n"); 111 112 return; 113} 114 115static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev, 116 struct usbip_header *pdu) 117{ 118 struct vhci_unlink *unlink, *tmp; 119 120 spin_lock(&vdev->priv_lock); 121 122 list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) { 123 pr_info("unlink->seqnum %lu\n", unlink->seqnum); 124 if (unlink->seqnum == pdu->base.seqnum) { 125 usbip_dbg_vhci_rx("found pending unlink, %lu\n", 126 unlink->seqnum); 127 list_del(&unlink->list); 128 129 spin_unlock(&vdev->priv_lock); 130 return unlink; 131 } 132 } 133 134 spin_unlock(&vdev->priv_lock); 135 136 return NULL; 137} 138 139static void vhci_recv_ret_unlink(struct vhci_device *vdev, 140 struct usbip_header *pdu) 141{ 142 struct vhci_unlink *unlink; 143 struct urb *urb; 144 unsigned long flags; 145 146 usbip_dump_header(pdu); 147 148 unlink = dequeue_pending_unlink(vdev, pdu); 149 if (!unlink) { 150 pr_info("cannot find the pending unlink %u\n", 151 pdu->base.seqnum); 152 return; 153 } 154 155 spin_lock(&vdev->priv_lock); 156 urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum); 157 spin_unlock(&vdev->priv_lock); 158 159 if (!urb) { 160 /* 161 * I get the result of a unlink request. But, it seems that I 162 * already received the result of its submit result and gave 163 * back the URB. 164 */ 165 pr_info("the urb (seqnum %d) was already given backed\n", 166 pdu->base.seqnum); 167 } else { 168 usbip_dbg_vhci_rx("now giveback urb %p\n", urb); 169 170 /* If unlink is succeed, status is -ECONNRESET */ 171 urb->status = pdu->u.ret_unlink.status; 172 pr_info("urb->status %d\n", urb->status); 173 174 spin_lock_irqsave(&the_controller->lock, flags); 175 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb); 176 spin_unlock_irqrestore(&the_controller->lock, flags); 177 178 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, 179 urb->status); 180 } 181 182 kfree(unlink); 183} 184 185static int vhci_priv_tx_empty(struct vhci_device *vdev) 186{ 187 int empty = 0; 188 189 spin_lock(&vdev->priv_lock); 190 empty = list_empty(&vdev->priv_rx); 191 spin_unlock(&vdev->priv_lock); 192 193 return empty; 194} 195 196/* recv a pdu */ 197static void vhci_rx_pdu(struct usbip_device *ud) 198{ 199 int ret; 200 struct usbip_header pdu; 201 struct vhci_device *vdev = container_of(ud, struct vhci_device, ud); 202 203 usbip_dbg_vhci_rx("Enter\n"); 204 205 memset(&pdu, 0, sizeof(pdu)); 206 207 /* 1. receive a pdu header */ 208 ret = usbip_recv(ud->tcp_socket, &pdu, sizeof(pdu)); 209 if (ret < 0) { 210 if (ret == -ECONNRESET) 211 pr_info("connection reset by peer\n"); 212 else if (ret == -EAGAIN) { 213 /* ignore if connection was idle */ 214 if (vhci_priv_tx_empty(vdev)) 215 return; 216 pr_info("connection timed out with pending urbs\n"); 217 } else if (ret != -ERESTARTSYS) 218 pr_info("xmit failed %d\n", ret); 219 220 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); 221 return; 222 } 223 if (ret == 0) { 224 pr_info("connection closed"); 225 usbip_event_add(ud, VDEV_EVENT_DOWN); 226 return; 227 } 228 if (ret != sizeof(pdu)) { 229 pr_err("received pdu size is %d, should be %d\n", ret, 230 (unsigned int)sizeof(pdu)); 231 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); 232 return; 233 } 234 235 usbip_header_correct_endian(&pdu, 0); 236 237 if (usbip_dbg_flag_vhci_rx) 238 usbip_dump_header(&pdu); 239 240 switch (pdu.base.command) { 241 case USBIP_RET_SUBMIT: 242 vhci_recv_ret_submit(vdev, &pdu); 243 break; 244 case USBIP_RET_UNLINK: 245 vhci_recv_ret_unlink(vdev, &pdu); 246 break; 247 default: 248 /* NOT REACHED */ 249 pr_err("unknown pdu %u\n", pdu.base.command); 250 usbip_dump_header(&pdu); 251 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP); 252 break; 253 } 254} 255 256int vhci_rx_loop(void *data) 257{ 258 struct usbip_device *ud = data; 259 260 while (!kthread_should_stop()) { 261 if (usbip_event_happened(ud)) 262 break; 263 264 vhci_rx_pdu(ud); 265 } 266 267 return 0; 268} 269