From d60cbe43b74d06e3a2a41f3f9565430b456b86bc Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Piotr=20Jaroszy=C5=84ski?= Date: Fri, 28 May 2010 01:09:22 +0200 Subject: [PATCH] [linux] Add the tap driver MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add the tap driver that can be used like: $ ./ipxe.linux --net tap,if=tap0,mac=00:0c:29:c5:39:a1 The if setting is mandatory. Signed-off-by: Piotr Jaroszyński Signed-off-by: Michael Brown --- src/config/config.c | 5 + src/config/defaults/linux.h | 2 + src/drivers/linux/tap.c | 249 ++++++++++++++++++++++++++++++++++++ src/include/ipxe/errfile.h | 1 + 4 files changed, 257 insertions(+) create mode 100644 src/drivers/linux/tap.c diff --git a/src/config/config.c b/src/config/config.c index 561e53d40..cb66e164e 100644 --- a/src/config/config.c +++ b/src/config/config.c @@ -263,3 +263,8 @@ REQUIRE_OBJECT ( gdbstub_cmd ); */ REQUIRE_OBJECT ( device ); REQUIRE_OBJECT ( embedded ); + +/* linux drivers aren't picked up by the parserom utility so drag them in here */ +#ifdef DRIVERS_LINUX +REQUIRE_OBJECT ( tap ); +#endif diff --git a/src/config/defaults/linux.h b/src/config/defaults/linux.h index a678aa4f1..901097fda 100644 --- a/src/config/defaults/linux.h +++ b/src/config/defaults/linux.h @@ -14,6 +14,8 @@ #define NAP_LINUX #define SMBIOS_LINUX +#define DRIVERS_LINUX + #define IMAGE_SCRIPT #endif /* CONFIG_DEFAULTS_LINUX_H */ diff --git a/src/drivers/linux/tap.c b/src/drivers/linux/tap.c new file mode 100644 index 000000000..c2cb7584f --- /dev/null +++ b/src/drivers/linux/tap.c @@ -0,0 +1,249 @@ +/* + * Copyright (C) 2010 Piotr Jaroszyński + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* This hack prevents pre-2.6.32 headers from redefining struct sockaddr */ +#define __GLIBC__ 2 +#include +#undef __GLIBC__ +#include +#include +#include + +#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)); + + netdev_link_up(netdev); + + if ((rc = register_netdev(netdev)) != 0) + goto err_register; + + /* 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; + if_setting->applied = 1; + + /* Apply rest of the settings */ + linux_apply_settings(&request->settings, &netdev->settings.settings); + + 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, +}; diff --git a/src/include/ipxe/errfile.h b/src/include/ipxe/errfile.h index 91dc19bcf..ad32ed1b8 100644 --- a/src/include/ipxe/errfile.h +++ b/src/include/ipxe/errfile.h @@ -128,6 +128,7 @@ FILE_LICENCE ( GPL2_OR_LATER ); #define ERRFILE_snponly ( ERRFILE_DRIVER | 0x005a0000 ) #define ERRFILE_jme ( ERRFILE_DRIVER | 0x005b0000 ) #define ERRFILE_virtio_net ( ERRFILE_DRIVER | 0x005c0000 ) +#define ERRFILE_tap ( ERRFILE_DRIVER | 0x005d0000 ) #define ERRFILE_scsi ( ERRFILE_DRIVER | 0x00700000 ) #define ERRFILE_arbel ( ERRFILE_DRIVER | 0x00710000 )