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. caller must hold vdev->priv_lock */
  25 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         list_for_each_entry_safe(priv, tmp, &vdev->priv_rx, list) {
  33                 if (priv->seqnum == seqnum) {
  34                         urb = priv->urb;
  35                         status = urb->status;
  36
  37                         usbip_dbg_vhci_rx("find urb %p vurb %p seqnum %u\n",
  38                                     urb, priv, seqnum);
  39
  40                         /* TODO: fix logic here to improve indent situtation */
  41                         if (status != -EINPROGRESS) {
  42                                 if (status == -ENOENT ||
  43                                      status == -ECONNRESET)
  44                                         dev_info(&urb->dev->dev,
  45                                                  "urb %p was unlinked "
  46                                                  "%ssynchronuously.\n", urb,
  47                                                  status == -ENOENT ? "" : "a");
  48                                 else
  49                                         dev_info(&urb->dev->dev,
  50                                                  "urb %p may be in a error, "
  51                                                  "status %d\n", urb, status);
  52                         }
  53
  54                         list_del(&priv->list);
  55                         kfree(priv);
  56                         urb->hcpriv = NULL;
  57
  58                         break;
  59                 }
  60         }
  61
  62         return urb;
  63 }
  64
  65 static void vhci_recv_ret_submit(struct vhci_device *vdev,
  66                                                 struct usbip_header *pdu)
  67 {
  68         struct usbip_device *ud = &vdev->ud;
  69         struct urb *urb;
  70
  71         spin_lock(&vdev->priv_lock);
  72
  73         urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
  74
  75         spin_unlock(&vdev->priv_lock);
  76
  77         if (!urb) {
  78                 usbip_uerr("cannot find a urb of seqnum %u\n",
  79                                                         pdu->base.seqnum);
  80                 usbip_uinfo("max seqnum %d\n",
  81                                         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 (usbip_dbg_flag_vhci_rx)
 102                 usbip_dump_urb(urb);
 103
 104
 105         usbip_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         usbip_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                 usbip_uinfo("unlink->seqnum %lu\n", unlink->seqnum);
 129                 if (unlink->seqnum == pdu->base.seqnum) {
 130                         usbip_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                 usbip_uinfo("cannot find the pending unlink %u\n",
 156                                                         pdu->base.seqnum);
 157                 return;
 158         }
 159
 160         spin_lock(&vdev->priv_lock);
 161
 162         urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
 163
 164         spin_unlock(&vdev->priv_lock);
 165
 166         if (!urb) {
 167                 /*
 168                  * I get the result of a unlink request. But, it seems that I
 169                  * already received the result of its submit result and gave
 170                  * back the URB.
 171                  */
 172                 usbip_uinfo("the urb (seqnum %d) was already given backed\n",
 173                                                         pdu->base.seqnum);
 174         } else {
 175                 usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
 176
 177                 /* If unlink is succeed, status is -ECONNRESET */
 178                 urb->status = pdu->u.ret_unlink.status;
 179                 usbip_uinfo("%d\n", urb->status);
 180
 181                 spin_lock(&the_controller->lock);
 182                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 183                 spin_unlock(&the_controller->lock);
 184
 185                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 186                                                                 urb->status);
 187         }
 188
 189         kfree(unlink);
 190
 191         return;
 192 }
 193
 194 /* recv a pdu */
 195 static void vhci_rx_pdu(struct usbip_device *ud)
 196 {
 197         int ret;
 198         struct usbip_header pdu;
 199         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 200
 201
 202         usbip_dbg_vhci_rx("Enter\n");
 203
 204         memset(&pdu, 0, sizeof(pdu));
 205
 206
 207         /* 1. receive a pdu header */
 208         ret = usbip_xmit(0, ud->tcp_socket, (char *) &pdu, sizeof(pdu), 0);
 209         if (ret != sizeof(pdu)) {
 210                 usbip_uerr("receiving pdu failed! size is %d, should be %d\n",
 211                                         ret, (unsigned int)sizeof(pdu));
 212                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 213                 return;
 214         }
 215
 216         usbip_header_correct_endian(&pdu, 0);
 217
 218         if (usbip_dbg_flag_vhci_rx)
 219                 usbip_dump_header(&pdu);
 220
 221         switch (pdu.base.command) {
 222         case USBIP_RET_SUBMIT:
 223                 vhci_recv_ret_submit(vdev, &pdu);
 224                 break;
 225         case USBIP_RET_UNLINK:
 226                 vhci_recv_ret_unlink(vdev, &pdu);
 227                 break;
 228         default:
 229                 /* NOTREACHED */
 230                 usbip_uerr("unknown pdu %u\n", pdu.base.command);
 231                 usbip_dump_header(&pdu);
 232                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 233         }
 234 }
 235
 236
 237 /*-------------------------------------------------------------------------*/
 238
 239 void vhci_rx_loop(struct usbip_task *ut)
 240 {
 241         struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_rx);
 242
 243
 244         while (1) {
 245                 if (signal_pending(current)) {
 246                         usbip_dbg_vhci_rx("signal catched!\n");
 247                         break;
 248                 }
 249
 250
 251                 if (usbip_event_happened(ud))
 252                         break;
 253
 254                 vhci_rx_pdu(ud);
 255         }
 256 }
 257