LXR qemu/bt-vhci.c

   1/*
   2 * Support for host VHCIs inside qemu scatternets.
   3 *
   4 * Copyright (C) 2008 Andrzej Zaborowski  <balrog@zabor.org>
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as
   8 * published by the Free Software Foundation; either version 2 or
   9 * (at your option) version 3 of the License.
  10 *
  11 * This program is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License along
  17 * with this program; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20#include "qemu/osdep.h"
  21#include "sysemu/bt.h"
  22#include "hw/bt.h"
  23#include "qemu/main-loop.h"
  24
  25#define VHCI_DEV        "/dev/vhci"
  26#define VHCI_UDEV       "/dev/hci_vhci"
  27
  28struct bt_vhci_s {
  29    int fd;
  30    struct HCIInfo *info;
  31
  32    uint8_t hdr[4096];
  33    int len;
  34};
  35
  36static void vhci_read(void *opaque)
  37{
  38    struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  39    uint8_t *pkt;
  40    int pktlen;
  41
  42    /* Seems that we can't read only the header first and then the amount
  43     * of data indicated in the header because Linux will discard everything
  44     * that's not been read in one go.  */
  45    s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  46
  47    if (s->len < 0) {
  48        fprintf(stderr, "qemu: error %i reading the PDU\n", errno);
  49        return;
  50    }
  51
  52    pkt = s->hdr;
  53    while (s->len --)
  54        switch (*pkt ++) {
  55        case HCI_COMMAND_PKT:
  56            if (s->len < 3)
  57                goto bad_pkt;
  58
  59            pktlen = MIN(pkt[2] + 3, s->len);
  60            s->info->cmd_send(s->info, pkt, pktlen);
  61            s->len -= pktlen;
  62            pkt += pktlen;
  63            break;
  64
  65        case HCI_ACLDATA_PKT:
  66            if (s->len < 4)
  67                goto bad_pkt;
  68
  69            pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
  70            s->info->acl_send(s->info, pkt, pktlen);
  71            s->len -= pktlen;
  72            pkt += pktlen;
  73            break;
  74
  75        case HCI_SCODATA_PKT:
  76            if (s->len < 3)
  77                goto bad_pkt;
  78
  79            pktlen = MIN(pkt[2] + 3, s->len);
  80            s->info->sco_send(s->info, pkt, pktlen);
  81            s->len -= pktlen;
  82            pkt += pktlen;
  83            break;
  84
  85        default:
  86        bad_pkt:
  87            fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
  88        }
  89}
  90
  91static void vhci_host_send(void *opaque,
  92                int type, const uint8_t *data, int len)
  93{
  94    struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  95#if 0
  96    uint8_t pkt = type;
  97    struct iovec iv[2];
  98
  99    iv[0].iov_base = &pkt;
 100    iv[0].iov_len  = 1;
 101    iv[1].iov_base = (void *) data;
 102    iv[1].iov_len  = len;
 103
 104    while (writev(s->fd, iv, 2) < 0)
 105        if (errno != EAGAIN && errno != EINTR) {
 106            fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 107                            errno);
 108            return;
 109        }
 110#else
 111    /* Apparently VHCI wants us to write everything in one chunk :-(  */
 112    static uint8_t buf[4096];
 113
 114    buf[0] = type;
 115    memcpy(buf + 1, data, len);
 116
 117    while (write(s->fd, buf, len + 1) < 0)
 118        if (errno != EAGAIN && errno != EINTR) {
 119            fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 120                            errno);
 121            return;
 122        }
 123#endif
 124}
 125
 126static void vhci_out_hci_packet_event(void *opaque,
 127                const uint8_t *data, int len)
 128{
 129    vhci_host_send(opaque, HCI_EVENT_PKT, data, len);
 130}
 131
 132static void vhci_out_hci_packet_acl(void *opaque,
 133                const uint8_t *data, int len)
 134{
 135    vhci_host_send(opaque, HCI_ACLDATA_PKT, data, len);
 136}
 137
 138void bt_vhci_init(struct HCIInfo *info)
 139{
 140    struct bt_vhci_s *s;
 141    int err[2];
 142    int fd;
 143
 144    fd = open(VHCI_DEV, O_RDWR);
 145    err[0] = errno;
 146    if (fd < 0) {
 147        fd = open(VHCI_UDEV, O_RDWR);
 148        err[1] = errno;
 149    }
 150
 151    if (fd < 0) {
 152        fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 153                        VHCI_DEV, strerror(err[0]), err[0]);
 154        fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 155                        VHCI_UDEV, strerror(err[1]), err[1]);
 156        exit(-1);
 157    }
 158
 159    s = g_malloc0(sizeof(struct bt_vhci_s));
 160    s->fd = fd;
 161    s->info = info ?: qemu_next_hci();
 162    s->info->opaque = s;
 163    s->info->evt_recv = vhci_out_hci_packet_event;
 164    s->info->acl_recv = vhci_out_hci_packet_acl;
 165
 166    qemu_set_fd_handler(s->fd, vhci_read, NULL, s);
 167}
 168