--- /dev/null
+/*
+ * Copyright (C) 2010 Piotr Jaroszyński <p.jaroszynski@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <linux_api.h>
+#include <ipxe/list.h>
+#include <ipxe/linux.h>
+#include <ipxe/malloc.h>
+#include <ipxe/device.h>
+#include <ipxe/netdevice.h>
+#include <ipxe/iobuf.h>
+#include <ipxe/ethernet.h>
+#include <ipxe/settings.h>
+#include <ipxe/socket.h>
+
+/* This hack prevents pre-2.6.32 headers from redefining struct sockaddr */
+#define __GLIBC__ 2
+#include <linux/socket.h>
+#undef __GLIBC__
+#include <linux/if.h>
+#include <linux/if_ether.h>
+#include <linux/if_tun.h>
+
+#define RX_BUF_SIZE 1536
+
+/** @file
+ *
+ * The TAP driver.
+ *
+ * The TAP is a Virtual Ethernet network device.
+ */
+
+struct tap_nic {
+ /** Tap interface name */
+ char * interface;
+ /** File descriptor of the opened tap device */
+ int fd;
+};
+
+/** Open the TAP device */
+static int tap_open(struct net_device * netdev)
+{
+ struct tap_nic * nic = netdev->priv;
+ struct ifreq ifr;
+ int ret;
+
+ nic->fd = linux_open("/dev/net/tun", O_RDWR);
+ if (nic->fd < 0) {
+ DBGC(nic, "tap %p open('/dev/net/tun') = %d (%s)\n", nic, nic->fd, linux_strerror(linux_errno));
+ return nic->fd;
+ }
+
+ memset(&ifr, 0, sizeof(ifr));
+ /* IFF_NO_PI for no extra packet information */
+ ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
+ strncpy(ifr.ifr_name, nic->interface, IFNAMSIZ);
+ DBGC(nic, "tap %p interface = '%s'\n", nic, nic->interface);
+
+ ret = linux_ioctl(nic->fd, TUNSETIFF, &ifr);
+
+ if (ret != 0) {
+ DBGC(nic, "tap %p ioctl(%d, ...) = %d (%s)\n", nic, nic->fd, ret, linux_strerror(linux_errno));
+ linux_close(nic->fd);
+ return ret;
+ }
+
+ /* Set nonblocking mode to make tap_poll easier */
+ ret = linux_fcntl(nic->fd, F_SETFL, O_NONBLOCK);
+
+ if (ret != 0) {
+ DBGC(nic, "tap %p fcntl(%d, ...) = %d (%s)\n", nic, nic->fd, ret, linux_strerror(linux_errno));
+ linux_close(nic->fd);
+ return ret;
+ }
+
+ return 0;
+}
+
+/** Close the TAP device */
+static void tap_close(struct net_device *netdev)
+{
+ struct tap_nic * nic = netdev->priv;
+ linux_close(nic->fd);
+}
+
+/**
+ * Transmit an ethernet packet.
+ *
+ * The packet can be written to the TAP device and marked as complete immediately.
+ */
+static int tap_transmit(struct net_device *netdev, struct io_buffer *iobuf)
+{
+ struct tap_nic * nic = netdev->priv;
+ int rc;
+
+ /* Pad and align packet */
+ iob_pad(iobuf, ETH_ZLEN);
+
+ rc = linux_write(nic->fd, iobuf->data, iobuf->tail - iobuf->data);
+ DBGC2(nic, "tap %p wrote %d bytes\n", nic, rc);
+ netdev_tx_complete(netdev, iobuf);
+
+ return 0;
+}
+
+/** Poll for new packets */
+static void tap_poll(struct net_device *netdev)
+{
+ struct tap_nic * nic = netdev->priv;
+ struct pollfd pfd;
+ struct io_buffer * iobuf;
+ int r;
+
+ pfd.fd = nic->fd;
+ pfd.events = POLLIN;
+ if (linux_poll(&pfd, 1, 0) == -1) {
+ DBGC(nic, "tap %p poll failed (%s)\n", nic, linux_strerror(linux_errno));
+ return;
+ }
+ if ((pfd.revents & POLLIN) == 0)
+ return;
+
+ /* At this point we know there is at least one new packet to be read */
+
+ iobuf = alloc_iob(RX_BUF_SIZE);
+ if (! iobuf)
+ goto allocfail;
+
+ while ((r = linux_read(nic->fd, iobuf->data, RX_BUF_SIZE)) > 0) {
+ DBGC2(nic, "tap %p read %d bytes\n", nic, r);
+
+ iob_put(iobuf, r);
+ netdev_rx(netdev, iobuf);
+
+ iobuf = alloc_iob(RX_BUF_SIZE);
+ if (! iobuf)
+ goto allocfail;
+ }
+
+ free_iob(iobuf);
+ return;
+
+allocfail:
+ DBGC(nic, "tap %p alloc_iob failed\n", nic);
+}
+
+/**
+ * Set irq.
+ *
+ * Not used on linux, provide a dummy implementation.
+ */
+static void tap_irq(struct net_device *netdev, int enable)
+{
+ struct tap_nic *nic = netdev->priv;
+
+ DBGC(nic, "tap %p irq enable = %d\n", nic, enable);
+}
+
+/** Tap operations */
+static struct net_device_operations tap_operations = {
+ .open = tap_open,
+ .close = tap_close,
+ .transmit = tap_transmit,
+ .poll = tap_poll,
+ .irq = tap_irq,
+};
+
+/** Handle a device request for the tap driver */
+static int tap_probe(struct linux_device *device, struct linux_device_request *request)
+{
+ struct linux_setting *if_setting;
+ struct net_device *netdev;
+ struct tap_nic *nic;
+ int rc;
+
+ netdev = alloc_etherdev(sizeof(*nic));
+ if (! netdev)
+ return -ENOMEM;
+
+ netdev_init(netdev, &tap_operations);
+ nic = netdev->priv;
+ linux_set_drvdata(device, netdev);
+ netdev->dev = &device->dev;
+ memset(nic, 0, sizeof(*nic));
+
+ /* Look for the mandatory if setting */
+ if_setting = linux_find_setting("if", &request->settings);
+
+ /* No if setting */
+ if (! if_setting) {
+ printf("tap missing a mandatory if setting\n");
+ rc = -EINVAL;
+ goto err_settings;
+ }
+
+ nic->interface = if_setting->value;
+ snprintf ( device->dev.name, sizeof ( device->dev.name ), "%s",
+ nic->interface );
+ device->dev.desc.bus_type = BUS_TYPE_TAP;
+ if_setting->applied = 1;
+
+ /* Apply rest of the settings */
+ linux_apply_settings(&request->settings, &netdev->settings.settings);
+
+ /* Register network device */
+ if ((rc = register_netdev(netdev)) != 0)
+ goto err_register;
+
+ netdev_link_up(netdev);
+
+ return 0;
+
+err_settings:
+ unregister_netdev(netdev);
+err_register:
+ netdev_nullify(netdev);
+ netdev_put(netdev);
+ return rc;
+}
+
+/** Remove the device */
+static void tap_remove(struct linux_device *device)
+{
+ struct net_device *netdev = linux_get_drvdata(device);
+ unregister_netdev(netdev);
+ netdev_nullify(netdev);
+ netdev_put(netdev);
+}
+
+/** Tap linux_driver */
+struct linux_driver tap_driver __linux_driver = {
+ .name = "tap",
+ .probe = tap_probe,
+ .remove = tap_remove,
+ .can_probe = 1,
+};
Code Review / kvmfornfv.git / blobdiff