diff options
Diffstat (limited to 'sys/net')
| -rw-r--r-- | sys/net/if_edsc.c | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/sys/net/if_edsc.c b/sys/net/if_edsc.c new file mode 100644 index 0000000..51aca53 --- /dev/null +++ b/sys/net/if_edsc.c @@ -0,0 +1,349 @@ +/*- + * Copyright (c) 1982, 1986, 1993 + * The Regents of the University of California. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following edsclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following edsclaimer in the + * documentation and/or other materials provided with the distribution. + * 4. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE EDSCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * From: @(#)if_loop.c 8.1 (Berkeley) 6/10/93 + * $FreeBSD$ + */ + +/* + * Discard interface driver for protocol testing and timing. + * Mimics an Ethernet device so that VLANs can be attached to it etc. + */ + +#include <sys/param.h> /* types, important constants */ +#include <sys/kernel.h> /* SYSINIT for load-time initializations */ +#include <sys/malloc.h> /* malloc(9) */ +#include <sys/module.h> /* module(9) */ +#include <sys/mbuf.h> /* mbuf(9) */ +#include <sys/socket.h> /* struct ifreq */ +#include <sys/sockio.h> /* socket ioctl's */ +/* #include <sys/systm.h> if you need printf(9) or other all-purpose globals */ + +#include <net/bpf.h> /* bpf(9) */ +#include <net/ethernet.h> /* Ethernet related constants and types */ +#include <net/if.h> /* basic network interface related things */ +#include <net/if_clone.h> /* network interface cloning */ +#include <net/if_types.h> /* IFT_ETHER and friends */ +#include <net/if_var.h> /* struct ifnet and other kernel-only stuff */ + +/* + * Software configuration of an interface instance. + */ +struct edsc_softc { + struct ifnet *sc_ifp; /* must be first */ +}; + +/* + * Simple cloning methods. + * IFC_SIMPLE_DECLARE() expects precisely these names. + */ +static int edsc_clone_create(struct if_clone *, int, caddr_t); +static void edsc_clone_destroy(struct ifnet *); + +/* + * Interface driver methods. + */ +static void edsc_init(void *dummy); +/* static void edsc_input(struct ifnet *ifp, struct mbuf *m); would be here */ +static int edsc_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data); +static void edsc_start(struct ifnet *ifp); + +/* + * We'll allocate softc instances from this. + */ +static MALLOC_DEFINE(M_EDSC, "edsc", "Ethernet discard interface"); + +/* + * Attach to the interface cloning framework under the name of "edsc". + * The second argument is the number of units to be created from + * the outset. It's also the minimum number of units allowed. + * We don't want any units created as soon as the driver is loaded. + */ +IFC_SIMPLE_DECLARE(edsc, 0); + +/* + * Create an interface instance. + */ +static int +edsc_clone_create(struct if_clone *ifc, int unit, caddr_t params) +{ + struct edsc_softc *sc; + struct ifnet *ifp; + static u_char eaddr[ETHER_ADDR_LEN]; /* 0:0:0:0:0:0 */ + + /* + * Allocate soft and ifnet structures. Link each to the other. + */ + sc = malloc(sizeof(struct edsc_softc), M_EDSC, M_WAITOK | M_ZERO); + ifp = sc->sc_ifp = if_alloc(IFT_ETHER); + if (ifp == NULL) { + free(sc, M_EDSC); + return (ENOSPC); + } + + ifp->if_softc = sc; + + /* + * Get a name for this particular interface in its ifnet structure. + */ + if_initname(ifp, ifc->ifc_name, unit); + + /* + * Typical Ethernet interface flags: we can do broadcast and + * multicast but can't hear our own broadcasts or multicasts. + */ + ifp->if_flags = IFF_BROADCAST | IFF_MULTICAST | IFF_SIMPLEX; + + /* + * We can pretent we have the whole set of hardware features + * because we just discard all packets we get from the upper layer. + * However, the features are disabled initially. They can be + * enabled via edsc_ioctl() when needed. + */ + ifp->if_capabilities = + IFCAP_VLAN_MTU | IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_HWCSUM | + IFCAP_HWCSUM | IFCAP_TSO | + IFCAP_JUMBO_MTU; + ifp->if_capenable = 0; + + /* + * Set the interface driver methods. + */ + ifp->if_init = edsc_init; + /* ifp->if_input = edsc_input; */ + ifp->if_ioctl = edsc_ioctl; + ifp->if_start = edsc_start; + + /* + * Set the maximum output queue length from the global parameter. + */ + ifp->if_snd.ifq_maxlen = ifqmaxlen; + + /* + * Do ifnet initializations common to all Ethernet drivers + * and attach to the network interface framework. + * TODO: Pick a non-zero link level address. + */ + ether_ifattach(ifp, eaddr); + + /* + * Now we can mark the interface as running, i.e., ready + * for operation. + */ + ifp->if_drv_flags |= IFF_DRV_RUNNING; + + return (0); +} + +/* + * Destroy an interface instance. + */ +static void +edsc_clone_destroy(struct ifnet *ifp) +{ + struct edsc_softc *sc = ifp->if_softc; + + /* + * Detach from the network interface framework. + */ + ether_ifdetach(ifp); + + /* + * Free memory occupied by ifnet and softc. + */ + if_free(ifp); + free(sc, M_EDSC); +} + +/* + * This method is invoked from ether_ioctl() when it's time + * to bring up the hardware. + */ +static void +edsc_init(void *dummy) +{ +#if 0 /* what a hardware driver would do here... */ + struct edsc_soft *sc = (struct edsc_softc *)dummy; + struct ifnet *ifp = sc->sc_ifp; + + /* blah-blah-blah */ +#endif +} + +/* + * Network interfaces are controlled via the ioctl(2) syscall. + */ +static int +edsc_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data) +{ + struct ifreq *ifr = (struct ifreq *)data; + + switch (cmd) { + case SIOCSIFCAP: +#if 1 + /* + * Just turn on any capabilities requested. + * The generic ifioctl() function has already made sure + * that they are supported, i.e., set in if_capabilities. + */ + ifp->if_capenable = ifr->ifr_reqcap; +#else + /* + * A h/w driver would need to analyze the requested + * bits and program the hardware, e.g.: + */ + mask = ifp->if_capenable ^ ifr->ifr_reqcap; + + if (mask & IFCAP_VLAN_HWTAGGING) { + ifp->if_capenable ^= IFCAP_VLAN_HWTAGGING; + + if (ifp->if_capenable & IFCAP_VLAN_HWTAGGING) + /* blah-blah-blah */ + else + /* etc-etc-etc */ + } +#endif + break; + + default: + /* + * Offload the rest onto the common Ethernet handler. + */ + return (ether_ioctl(ifp, cmd, data)); + } + + return (0); +} + +/* + * Process the output queue. + */ +static void +edsc_start(struct ifnet *ifp) +{ + struct mbuf *m; + + /* + * A hardware interface driver can set IFF_DRV_OACTIVE + * in ifp->if_drv_flags: + * + * ifp->if_drv_flags |= IFF_DRV_OACTIVE; + * + * to prevent if_start from being invoked again while the + * transmission is under way. The flag is to protect the + * device's transmitter, not the method itself. The output + * queue is locked and several threads can process it in + * parallel safely, so the driver can use other means to + * serialize access to the transmitter. + * + * If using IFF_DRV_OACTIVE, the driver should clear the flag + * not earlier than the current transmission is complete, e.g., + * upon an interrupt from the device, not just before returning + * from if_start. This method merely starts the transmission, + * which may proceed asynchronously. + */ + + /* + * We loop getting packets from the queue until it's empty. + * A h/w driver would loop until the device can accept more + * data into its buffer, or while there are free transmit + * descriptors, or whatever. + */ + for (;;) { + /* + * Try to dequeue one packet. Stop if the queue is empty. + * Use IF_DEQUEUE() here if ALTQ(9) support is unneeded. + */ + IFQ_DEQUEUE(&ifp->if_snd, m); + if (m == NULL) + break; + + /* + * Let bpf(9) at the packet. + */ + BPF_MTAP(ifp, m); + + /* + * Update the interface counters. + */ + ifp->if_obytes += m->m_pkthdr.len; + ifp->if_opackets++; + + /* + * Finally, just drop the packet. + * TODO: Reply to ARP requests unless IFF_NOARP is set. + */ + m_freem(m); + } + + /* + * ifp->if_drv_flags &= ~IFF_DRV_OACTIVE; + * would be here only if the transmission were synchronous. + */ +} + +/* + * This function provides handlers for module events, namely load and unload. + */ +static int +edsc_modevent(module_t mod, int type, void *data) +{ + + switch (type) { + case MOD_LOAD: + /* + * Connect to the network interface cloning framework. + */ + if_clone_attach(&edsc_cloner); + break; + + case MOD_UNLOAD: + /* + * Disconnect from the cloning framework. + * Existing interfaces will be disposed of properly. + */ + if_clone_detach(&edsc_cloner); + break; + + default: + /* + * There are other event types, but we don't handle them. + * See module(9). + */ + return (EOPNOTSUPP); + } + return (0); +} + +static moduledata_t edsc_mod = { + "if_edsc", /* name */ + edsc_modevent, /* event handler */ + NULL /* additional data */ +}; + +DECLARE_MODULE(if_edsc, edsc_mod, SI_SUB_PSEUDO, SI_ORDER_ANY); |
