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         unsigned long flags;
  71
  72         spin_lock(&vdev->priv_lock);
  73
  74         urb = pickup_urb_and_free_priv(vdev, pdu->base.seqnum);
  75
  76         spin_unlock(&vdev->priv_lock);
  77
  78         if (!urb) {
  79                 usbip_uerr("cannot find a urb of seqnum %u\n",
  80                                                         pdu->base.seqnum);
  81                 usbip_uinfo("max seqnum %d\n",
  82                                         atomic_read(&the_controller->seqnum));
  83                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
  84                 return;
  85         }
  86
  87
  88         /* unpack the pdu to a urb */
  89         usbip_pack_pdu(pdu, urb, USBIP_RET_SUBMIT, 0);
  90
  91
  92         /* recv transfer buffer */
  93         if (usbip_recv_xbuff(ud, urb) < 0)
  94                 return;
  95
  96
  97         /* recv iso_packet_descriptor */
  98         if (usbip_recv_iso(ud, urb) < 0)
  99                 return;
 100
 101         /* restore the padding in iso packets */
 102         if (usbip_pad_iso(ud, urb) < 0)
 103                 return;
 104
 105         if (usbip_dbg_flag_vhci_rx)
 106                 usbip_dump_urb(urb);
 107
 108
 109         usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
 110
 111         spin_lock_irqsave(&the_controller->lock, flags);
 112         usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 113         spin_unlock_irqrestore(&the_controller->lock, flags);
 114
 115         usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb, urb->status);
 116
 117
 118         usbip_dbg_vhci_rx("Leave\n");
 119
 120         return;
 121 }
 122
 123
 124 static struct vhci_unlink *dequeue_pending_unlink(struct vhci_device *vdev,
 125                 struct usbip_header *pdu)
 126 {
 127         struct vhci_unlink *unlink, *tmp;
 128
 129         spin_lock(&vdev->priv_lock);
 130
 131         list_for_each_entry_safe(unlink, tmp, &vdev->unlink_rx, list) {
 132                 usbip_uinfo("unlink->seqnum %lu\n", unlink->seqnum);
 133                 if (unlink->seqnum == pdu->base.seqnum) {
 134                         usbip_dbg_vhci_rx("found pending unlink, %lu\n",
 135                                                         unlink->seqnum);
 136                         list_del(&unlink->list);
 137
 138                         spin_unlock(&vdev->priv_lock);
 139                         return unlink;
 140                 }
 141         }
 142
 143         spin_unlock(&vdev->priv_lock);
 144
 145         return NULL;
 146 }
 147
 148
 149 static void vhci_recv_ret_unlink(struct vhci_device *vdev,
 150                                                 struct usbip_header *pdu)
 151 {
 152         struct vhci_unlink *unlink;
 153         struct urb *urb;
 154         unsigned long flags;
 155
 156         usbip_dump_header(pdu);
 157
 158         unlink = dequeue_pending_unlink(vdev, pdu);
 159         if (!unlink) {
 160                 usbip_uinfo("cannot find the pending unlink %u\n",
 161                                                         pdu->base.seqnum);
 162                 return;
 163         }
 164
 165         spin_lock(&vdev->priv_lock);
 166
 167         urb = pickup_urb_and_free_priv(vdev, unlink->unlink_seqnum);
 168
 169         spin_unlock(&vdev->priv_lock);
 170
 171         if (!urb) {
 172                 /*
 173                  * I get the result of a unlink request. But, it seems that I
 174                  * already received the result of its submit result and gave
 175                  * back the URB.
 176                  */
 177                 usbip_uinfo("the urb (seqnum %d) was already given backed\n",
 178                                                         pdu->base.seqnum);
 179         } else {
 180                 usbip_dbg_vhci_rx("now giveback urb %p\n", urb);
 181
 182                 /* If unlink is succeed, status is -ECONNRESET */
 183                 urb->status = pdu->u.ret_unlink.status;
 184                 usbip_uinfo("%d\n", urb->status);
 185
 186                 spin_lock_irqsave(&the_controller->lock, flags);
 187                 usb_hcd_unlink_urb_from_ep(vhci_to_hcd(the_controller), urb);
 188                 spin_unlock_irqrestore(&the_controller->lock, flags);
 189
 190                 usb_hcd_giveback_urb(vhci_to_hcd(the_controller), urb,
 191                                                                 urb->status);
 192         }
 193
 194         kfree(unlink);
 195
 196         return;
 197 }
 198
 199 /* recv a pdu */
 200 static void vhci_rx_pdu(struct usbip_device *ud)
 201 {
 202         int ret;
 203         struct usbip_header pdu;
 204         struct vhci_device *vdev = container_of(ud, struct vhci_device, ud);
 205
 206
 207         usbip_dbg_vhci_rx("Enter\n");
 208
 209         memset(&pdu, 0, sizeof(pdu));
 210
 211
 212         /* 1. receive a pdu header */
 213         ret = usbip_xmit(0, ud->tcp_socket, (char *) &pdu, sizeof(pdu), 0);
 214         if (ret != sizeof(pdu)) {
 215                 usbip_uerr("receiving pdu failed! size is %d, should be %d\n",
 216                                         ret, (unsigned int)sizeof(pdu));
 217                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 218                 return;
 219         }
 220
 221         usbip_header_correct_endian(&pdu, 0);
 222
 223         if (usbip_dbg_flag_vhci_rx)
 224                 usbip_dump_header(&pdu);
 225
 226         switch (pdu.base.command) {
 227         case USBIP_RET_SUBMIT:
 228                 vhci_recv_ret_submit(vdev, &pdu);
 229                 break;
 230         case USBIP_RET_UNLINK:
 231                 vhci_recv_ret_unlink(vdev, &pdu);
 232                 break;
 233         default:
 234                 /* NOTREACHED */
 235                 usbip_uerr("unknown pdu %u\n", pdu.base.command);
 236                 usbip_dump_header(&pdu);
 237                 usbip_event_add(ud, VDEV_EVENT_ERROR_TCP);
 238         }
 239 }
 240
 241
 242 /*-------------------------------------------------------------------------*/
 243
 244 void vhci_rx_loop(struct usbip_task *ut)
 245 {
 246         struct usbip_device *ud = container_of(ut, struct usbip_device, tcp_rx);
 247
 248
 249         while (1) {
 250                 if (signal_pending(current)) {
 251                         usbip_dbg_vhci_rx("signal catched!\n");
 252                         break;
 253                 }
 254
 255
 256                 if (usbip_event_happened(ud))
 257                         break;
 258
 259                 vhci_rx_pdu(ud);
 260         }
 261 }
 262