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 "qemu-common.h"
  22#include "sysemu/bt.h"
  23#include "hw/bt.h"
  24#include "qemu/main-loop.h"
  25
  26#define VHCI_DEV        "/dev/vhci"
  27#define VHCI_UDEV       "/dev/hci_vhci"
  28
  29struct bt_vhci_s {
  30    int fd;
  31    struct HCIInfo *info;
  32
  33    uint8_t hdr[4096];
  34    int len;
  35};
  36
  37static void vhci_read(void *opaque)
  38{
  39    struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  40    uint8_t *pkt;
  41    int pktlen;
  42
  43    /* Seems that we can't read only the header first and then the amount
  44     * of data indicated in the header because Linux will discard everything
  45     * that's not been read in one go.  */
  46    s->len = read(s->fd, s->hdr, sizeof(s->hdr));
  47
  48    if (s->len < 0) {
  49        fprintf(stderr, "qemu: error %i reading the PDU\n", errno);
  50        return;
  51    }
  52
  53    pkt = s->hdr;
  54    while (s->len --)
  55        switch (*pkt ++) {
  56        case HCI_COMMAND_PKT:
  57            if (s->len < 3)
  58                goto bad_pkt;
  59
  60            pktlen = MIN(pkt[2] + 3, s->len);
  61            s->info->cmd_send(s->info, pkt, pktlen);
  62            s->len -= pktlen;
  63            pkt += pktlen;
  64            break;
  65
  66        case HCI_ACLDATA_PKT:
  67            if (s->len < 4)
  68                goto bad_pkt;
  69
  70            pktlen = MIN(((pkt[3] << 8) | pkt[2]) + 4, s->len);
  71            s->info->acl_send(s->info, pkt, pktlen);
  72            s->len -= pktlen;
  73            pkt += pktlen;
  74            break;
  75
  76        case HCI_SCODATA_PKT:
  77            if (s->len < 3)
  78                goto bad_pkt;
  79
  80            pktlen = MIN(pkt[2] + 3, s->len);
  81            s->info->sco_send(s->info, pkt, pktlen);
  82            s->len -= pktlen;
  83            pkt += pktlen;
  84            break;
  85
  86        default:
  87        bad_pkt:
  88            fprintf(stderr, "qemu: bad HCI packet type %02x\n", pkt[-1]);
  89        }
  90}
  91
  92static void vhci_host_send(void *opaque,
  93                int type, const uint8_t *data, int len)
  94{
  95    struct bt_vhci_s *s = (struct bt_vhci_s *) opaque;
  96#if 0
  97    uint8_t pkt = type;
  98    struct iovec iv[2];
  99
 100    iv[0].iov_base = &pkt;
 101    iv[0].iov_len  = 1;
 102    iv[1].iov_base = (void *) data;
 103    iv[1].iov_len  = len;
 104
 105    while (writev(s->fd, iv, 2) < 0)
 106        if (errno != EAGAIN && errno != EINTR) {
 107            fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 108                            errno);
 109            return;
 110        }
 111#else
 112    /* Apparently VHCI wants us to write everything in one chunk :-(  */
 113    static uint8_t buf[4096];
 114
 115    buf[0] = type;
 116    memcpy(buf + 1, data, len);
 117
 118    while (write(s->fd, buf, len + 1) < 0)
 119        if (errno != EAGAIN && errno != EINTR) {
 120            fprintf(stderr, "qemu: error %i writing bluetooth packet.\n",
 121                            errno);
 122            return;
 123        }
 124#endif
 125}
 126
 127static void vhci_out_hci_packet_event(void *opaque,
 128                const uint8_t *data, int len)
 129{
 130    vhci_host_send(opaque, HCI_EVENT_PKT, data, len);
 131}
 132
 133static void vhci_out_hci_packet_acl(void *opaque,
 134                const uint8_t *data, int len)
 135{
 136    vhci_host_send(opaque, HCI_ACLDATA_PKT, data, len);
 137}
 138
 139void bt_vhci_init(struct HCIInfo *info)
 140{
 141    struct bt_vhci_s *s;
 142    int err[2];
 143    int fd;
 144
 145    fd = open(VHCI_DEV, O_RDWR);
 146    err[0] = errno;
 147    if (fd < 0) {
 148        fd = open(VHCI_UDEV, O_RDWR);
 149        err[1] = errno;
 150    }
 151
 152    if (fd < 0) {
 153        fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 154                        VHCI_DEV, strerror(err[0]), err[0]);
 155        fprintf(stderr, "qemu: Can't open `%s': %s (%i)\n",
 156                        VHCI_UDEV, strerror(err[1]), err[1]);
 157        exit(-1);
 158    }
 159
 160    s = g_malloc0(sizeof(struct bt_vhci_s));
 161    s->fd = fd;
 162    s->info = info ?: qemu_next_hci();
 163    s->info->opaque = s;
 164    s->info->evt_recv = vhci_out_hci_packet_event;
 165    s->info->acl_recv = vhci_out_hci_packet_acl;
 166
 167    qemu_set_fd_handler(s->fd, vhci_read, NULL, s);
 168}
 169