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, 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