opnsense-src/sys/dev/usb/net/usb_ethernet.c
Gleb Smirnoff b8a6e03fac Widen NET_EPOCH coverage.
When epoch(9) was introduced to network stack, it was basically
dropped in place of existing locking, which was mutexes and
rwlocks. For the sake of performance mutex covered areas were
as small as possible, so became epoch covered areas.

However, epoch doesn't introduce any contention, it just delays
memory reclaim. So, there is no point to minimise epoch covered
areas in sense of performance. Meanwhile entering/exiting epoch
also has non-zero CPU usage, so doing this less often is a win.

Not the least is also code maintainability. In the new paradigm
we can assume that at any stage of processing a packet, we are
inside network epoch. This makes coding both input and output
path way easier.

On output path we already enter epoch quite early - in the
ip_output(), in the ip6_output().

This patch does the same for the input path. All ISR processing,
network related callouts, other ways of packet injection to the
network stack shall be performed in net_epoch. Any leaf function
that walks network configuration now asserts epoch.

Tricky part is configuration code paths - ioctls, sysctls. They
also call into leaf functions, so some need to be changed.

This patch would introduce more epoch recursions (see EPOCH_TRACE)
than we had before. They will be cleaned up separately, as several
of them aren't trivial. Note, that unlike a lock recursion the
epoch recursion is safe and just wastes a bit of resources.

Reviewed by:	gallatin, hselasky, cy, adrian, kristof
Differential Revision:	https://reviews.freebsd.org/D19111
2019-10-07 22:40:05 +00:00

670 lines
15 KiB
C

/* $FreeBSD$ */
/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2009 Andrew Thompson (thompsa@FreeBSD.org)
*
* 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 disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 DISCLAIMED. IN NO EVENT SHALL THE AUTHOR 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/condvar.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mbuf.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/socket.h>
#include <sys/sockio.h>
#include <sys/sysctl.h>
#include <sys/sx.h>
#include <net/if.h>
#include <net/if_var.h>
#include <net/ethernet.h>
#include <net/if_types.h>
#include <net/if_media.h>
#include <net/if_vlan_var.h>
#include <dev/mii/mii.h>
#include <dev/mii/miivar.h>
#include <dev/usb/usb.h>
#include <dev/usb/usbdi.h>
#include <dev/usb/usb_process.h>
#include <dev/usb/net/usb_ethernet.h>
static SYSCTL_NODE(_net, OID_AUTO, ue, CTLFLAG_RD, 0,
"USB Ethernet parameters");
#define UE_LOCK(_ue) mtx_lock((_ue)->ue_mtx)
#define UE_UNLOCK(_ue) mtx_unlock((_ue)->ue_mtx)
#define UE_LOCK_ASSERT(_ue, t) mtx_assert((_ue)->ue_mtx, t)
MODULE_DEPEND(uether, usb, 1, 1, 1);
MODULE_DEPEND(uether, miibus, 1, 1, 1);
static struct unrhdr *ueunit;
static usb_proc_callback_t ue_attach_post_task;
static usb_proc_callback_t ue_promisc_task;
static usb_proc_callback_t ue_setmulti_task;
static usb_proc_callback_t ue_ifmedia_task;
static usb_proc_callback_t ue_tick_task;
static usb_proc_callback_t ue_start_task;
static usb_proc_callback_t ue_stop_task;
static void ue_init(void *);
static void ue_start(struct ifnet *);
static int ue_ifmedia_upd(struct ifnet *);
static void ue_watchdog(void *);
/*
* Return values:
* 0: success
* Else: device has been detached
*/
uint8_t
uether_pause(struct usb_ether *ue, unsigned int _ticks)
{
if (usb_proc_is_gone(&ue->ue_tq)) {
/* nothing to do */
return (1);
}
usb_pause_mtx(ue->ue_mtx, _ticks);
return (0);
}
static void
ue_queue_command(struct usb_ether *ue,
usb_proc_callback_t *fn,
struct usb_proc_msg *t0, struct usb_proc_msg *t1)
{
struct usb_ether_cfg_task *task;
UE_LOCK_ASSERT(ue, MA_OWNED);
if (usb_proc_is_gone(&ue->ue_tq)) {
return; /* nothing to do */
}
/*
* NOTE: The task cannot get executed before we drop the
* "sc_mtx" mutex. It is safe to update fields in the message
* structure after that the message got queued.
*/
task = (struct usb_ether_cfg_task *)
usb_proc_msignal(&ue->ue_tq, t0, t1);
/* Setup callback and self pointers */
task->hdr.pm_callback = fn;
task->ue = ue;
/*
* Start and stop must be synchronous!
*/
if ((fn == ue_start_task) || (fn == ue_stop_task))
usb_proc_mwait(&ue->ue_tq, t0, t1);
}
struct ifnet *
uether_getifp(struct usb_ether *ue)
{
return (ue->ue_ifp);
}
struct mii_data *
uether_getmii(struct usb_ether *ue)
{
return (device_get_softc(ue->ue_miibus));
}
void *
uether_getsc(struct usb_ether *ue)
{
return (ue->ue_sc);
}
static int
ue_sysctl_parent(SYSCTL_HANDLER_ARGS)
{
struct usb_ether *ue = arg1;
const char *name;
name = device_get_nameunit(ue->ue_dev);
return SYSCTL_OUT_STR(req, name);
}
int
uether_ifattach(struct usb_ether *ue)
{
int error;
/* check some critical parameters */
if ((ue->ue_dev == NULL) ||
(ue->ue_udev == NULL) ||
(ue->ue_mtx == NULL) ||
(ue->ue_methods == NULL))
return (EINVAL);
error = usb_proc_create(&ue->ue_tq, ue->ue_mtx,
device_get_nameunit(ue->ue_dev), USB_PRI_MED);
if (error) {
device_printf(ue->ue_dev, "could not setup taskqueue\n");
goto error;
}
/* fork rest of the attach code */
UE_LOCK(ue);
ue_queue_command(ue, ue_attach_post_task,
&ue->ue_sync_task[0].hdr,
&ue->ue_sync_task[1].hdr);
UE_UNLOCK(ue);
error:
return (error);
}
void
uether_ifattach_wait(struct usb_ether *ue)
{
UE_LOCK(ue);
usb_proc_mwait(&ue->ue_tq,
&ue->ue_sync_task[0].hdr,
&ue->ue_sync_task[1].hdr);
UE_UNLOCK(ue);
}
static void
ue_attach_post_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
struct ifnet *ifp;
int error;
char num[14]; /* sufficient for 32 bits */
/* first call driver's post attach routine */
ue->ue_methods->ue_attach_post(ue);
UE_UNLOCK(ue);
ue->ue_unit = alloc_unr(ueunit);
usb_callout_init_mtx(&ue->ue_watchdog, ue->ue_mtx, 0);
sysctl_ctx_init(&ue->ue_sysctl_ctx);
mbufq_init(&ue->ue_rxq, 0 /* unlimited length */);
error = 0;
CURVNET_SET_QUIET(vnet0);
ifp = if_alloc(IFT_ETHER);
if (ifp == NULL) {
device_printf(ue->ue_dev, "could not allocate ifnet\n");
goto fail;
}
ifp->if_softc = ue;
if_initname(ifp, "ue", ue->ue_unit);
if (ue->ue_methods->ue_attach_post_sub != NULL) {
ue->ue_ifp = ifp;
error = ue->ue_methods->ue_attach_post_sub(ue);
} else {
ifp->if_flags = IFF_BROADCAST | IFF_SIMPLEX | IFF_MULTICAST;
if (ue->ue_methods->ue_ioctl != NULL)
ifp->if_ioctl = ue->ue_methods->ue_ioctl;
else
ifp->if_ioctl = uether_ioctl;
ifp->if_start = ue_start;
ifp->if_init = ue_init;
IFQ_SET_MAXLEN(&ifp->if_snd, ifqmaxlen);
ifp->if_snd.ifq_drv_maxlen = ifqmaxlen;
IFQ_SET_READY(&ifp->if_snd);
ue->ue_ifp = ifp;
if (ue->ue_methods->ue_mii_upd != NULL &&
ue->ue_methods->ue_mii_sts != NULL) {
/* device_xxx() depends on this */
mtx_lock(&Giant);
error = mii_attach(ue->ue_dev, &ue->ue_miibus, ifp,
ue_ifmedia_upd, ue->ue_methods->ue_mii_sts,
BMSR_DEFCAPMASK, MII_PHY_ANY, MII_OFFSET_ANY, 0);
mtx_unlock(&Giant);
}
}
if (error) {
device_printf(ue->ue_dev, "attaching PHYs failed\n");
goto fail;
}
if_printf(ifp, "<USB Ethernet> on %s\n", device_get_nameunit(ue->ue_dev));
ether_ifattach(ifp, ue->ue_eaddr);
/* Tell upper layer we support VLAN oversized frames. */
if (ifp->if_capabilities & IFCAP_VLAN_MTU)
ifp->if_hdrlen = sizeof(struct ether_vlan_header);
CURVNET_RESTORE();
snprintf(num, sizeof(num), "%u", ue->ue_unit);
ue->ue_sysctl_oid = SYSCTL_ADD_NODE(&ue->ue_sysctl_ctx,
&SYSCTL_NODE_CHILDREN(_net, ue),
OID_AUTO, num, CTLFLAG_RD, NULL, "");
SYSCTL_ADD_PROC(&ue->ue_sysctl_ctx,
SYSCTL_CHILDREN(ue->ue_sysctl_oid), OID_AUTO,
"%parent", CTLTYPE_STRING | CTLFLAG_RD, ue, 0,
ue_sysctl_parent, "A", "parent device");
UE_LOCK(ue);
return;
fail:
CURVNET_RESTORE();
/* drain mbuf queue */
mbufq_drain(&ue->ue_rxq);
/* free unit */
free_unr(ueunit, ue->ue_unit);
if (ue->ue_ifp != NULL) {
if_free(ue->ue_ifp);
ue->ue_ifp = NULL;
}
UE_LOCK(ue);
return;
}
void
uether_ifdetach(struct usb_ether *ue)
{
struct ifnet *ifp;
/* wait for any post attach or other command to complete */
usb_proc_drain(&ue->ue_tq);
/* read "ifnet" pointer after taskqueue drain */
ifp = ue->ue_ifp;
if (ifp != NULL) {
/* we are not running any more */
UE_LOCK(ue);
ifp->if_drv_flags &= ~IFF_DRV_RUNNING;
UE_UNLOCK(ue);
/* drain any callouts */
usb_callout_drain(&ue->ue_watchdog);
/* detach miibus */
if (ue->ue_miibus != NULL) {
mtx_lock(&Giant); /* device_xxx() depends on this */
device_delete_child(ue->ue_dev, ue->ue_miibus);
mtx_unlock(&Giant);
}
/* detach ethernet */
ether_ifdetach(ifp);
/* free interface instance */
if_free(ifp);
/* free sysctl */
sysctl_ctx_free(&ue->ue_sysctl_ctx);
/* drain mbuf queue */
mbufq_drain(&ue->ue_rxq);
/* free unit */
free_unr(ueunit, ue->ue_unit);
}
/* free taskqueue, if any */
usb_proc_free(&ue->ue_tq);
}
uint8_t
uether_is_gone(struct usb_ether *ue)
{
return (usb_proc_is_gone(&ue->ue_tq));
}
void
uether_init(void *arg)
{
ue_init(arg);
}
static void
ue_init(void *arg)
{
struct usb_ether *ue = arg;
UE_LOCK(ue);
ue_queue_command(ue, ue_start_task,
&ue->ue_sync_task[0].hdr,
&ue->ue_sync_task[1].hdr);
UE_UNLOCK(ue);
}
static void
ue_start_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
struct ifnet *ifp = ue->ue_ifp;
UE_LOCK_ASSERT(ue, MA_OWNED);
ue->ue_methods->ue_init(ue);
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
return;
if (ue->ue_methods->ue_tick != NULL)
usb_callout_reset(&ue->ue_watchdog, hz, ue_watchdog, ue);
}
static void
ue_stop_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
UE_LOCK_ASSERT(ue, MA_OWNED);
usb_callout_stop(&ue->ue_watchdog);
ue->ue_methods->ue_stop(ue);
}
void
uether_start(struct ifnet *ifp)
{
ue_start(ifp);
}
static void
ue_start(struct ifnet *ifp)
{
struct usb_ether *ue = ifp->if_softc;
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
return;
UE_LOCK(ue);
ue->ue_methods->ue_start(ue);
UE_UNLOCK(ue);
}
static void
ue_promisc_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
ue->ue_methods->ue_setpromisc(ue);
}
static void
ue_setmulti_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
ue->ue_methods->ue_setmulti(ue);
}
int
uether_ifmedia_upd(struct ifnet *ifp)
{
return (ue_ifmedia_upd(ifp));
}
static int
ue_ifmedia_upd(struct ifnet *ifp)
{
struct usb_ether *ue = ifp->if_softc;
/* Defer to process context */
UE_LOCK(ue);
ue_queue_command(ue, ue_ifmedia_task,
&ue->ue_media_task[0].hdr,
&ue->ue_media_task[1].hdr);
UE_UNLOCK(ue);
return (0);
}
static void
ue_ifmedia_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
struct ifnet *ifp = ue->ue_ifp;
ue->ue_methods->ue_mii_upd(ifp);
}
static void
ue_watchdog(void *arg)
{
struct usb_ether *ue = arg;
struct ifnet *ifp = ue->ue_ifp;
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
return;
ue_queue_command(ue, ue_tick_task,
&ue->ue_tick_task[0].hdr,
&ue->ue_tick_task[1].hdr);
usb_callout_reset(&ue->ue_watchdog, hz, ue_watchdog, ue);
}
static void
ue_tick_task(struct usb_proc_msg *_task)
{
struct usb_ether_cfg_task *task =
(struct usb_ether_cfg_task *)_task;
struct usb_ether *ue = task->ue;
struct ifnet *ifp = ue->ue_ifp;
if ((ifp->if_drv_flags & IFF_DRV_RUNNING) == 0)
return;
ue->ue_methods->ue_tick(ue);
}
int
uether_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
{
struct usb_ether *ue = ifp->if_softc;
struct ifreq *ifr = (struct ifreq *)data;
struct mii_data *mii;
int error = 0;
switch (command) {
case SIOCSIFFLAGS:
UE_LOCK(ue);
if (ifp->if_flags & IFF_UP) {
if (ifp->if_drv_flags & IFF_DRV_RUNNING)
ue_queue_command(ue, ue_promisc_task,
&ue->ue_promisc_task[0].hdr,
&ue->ue_promisc_task[1].hdr);
else
ue_queue_command(ue, ue_start_task,
&ue->ue_sync_task[0].hdr,
&ue->ue_sync_task[1].hdr);
} else {
ue_queue_command(ue, ue_stop_task,
&ue->ue_sync_task[0].hdr,
&ue->ue_sync_task[1].hdr);
}
UE_UNLOCK(ue);
break;
case SIOCADDMULTI:
case SIOCDELMULTI:
UE_LOCK(ue);
ue_queue_command(ue, ue_setmulti_task,
&ue->ue_multi_task[0].hdr,
&ue->ue_multi_task[1].hdr);
UE_UNLOCK(ue);
break;
case SIOCGIFMEDIA:
case SIOCSIFMEDIA:
if (ue->ue_miibus != NULL) {
mii = device_get_softc(ue->ue_miibus);
error = ifmedia_ioctl(ifp, ifr, &mii->mii_media, command);
} else
error = ether_ioctl(ifp, command, data);
break;
default:
error = ether_ioctl(ifp, command, data);
break;
}
return (error);
}
static int
uether_modevent(module_t mod, int type, void *data)
{
switch (type) {
case MOD_LOAD:
ueunit = new_unrhdr(0, INT_MAX, NULL);
break;
case MOD_UNLOAD:
break;
default:
return (EOPNOTSUPP);
}
return (0);
}
static moduledata_t uether_mod = {
"uether",
uether_modevent,
0
};
struct mbuf *
uether_newbuf(void)
{
struct mbuf *m_new;
m_new = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR);
if (m_new == NULL)
return (NULL);
m_new->m_len = m_new->m_pkthdr.len = MCLBYTES;
m_adj(m_new, ETHER_ALIGN);
return (m_new);
}
int
uether_rxmbuf(struct usb_ether *ue, struct mbuf *m,
unsigned int len)
{
struct ifnet *ifp = ue->ue_ifp;
UE_LOCK_ASSERT(ue, MA_OWNED);
/* finalize mbuf */
if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
m->m_pkthdr.rcvif = ifp;
m->m_pkthdr.len = m->m_len = len;
/* enqueue for later when the lock can be released */
(void)mbufq_enqueue(&ue->ue_rxq, m);
return (0);
}
int
uether_rxbuf(struct usb_ether *ue, struct usb_page_cache *pc,
unsigned int offset, unsigned int len)
{
struct ifnet *ifp = ue->ue_ifp;
struct mbuf *m;
UE_LOCK_ASSERT(ue, MA_OWNED);
if (len < ETHER_HDR_LEN || len > MCLBYTES - ETHER_ALIGN)
return (1);
m = uether_newbuf();
if (m == NULL) {
if_inc_counter(ifp, IFCOUNTER_IQDROPS, 1);
return (ENOMEM);
}
usbd_copy_out(pc, offset, mtod(m, uint8_t *), len);
/* finalize mbuf */
if_inc_counter(ifp, IFCOUNTER_IPACKETS, 1);
m->m_pkthdr.rcvif = ifp;
m->m_pkthdr.len = m->m_len = len;
/* enqueue for later when the lock can be released */
(void)mbufq_enqueue(&ue->ue_rxq, m);
return (0);
}
void
uether_rxflush(struct usb_ether *ue)
{
struct ifnet *ifp = ue->ue_ifp;
struct epoch_tracker et;
struct mbuf *m, *n;
UE_LOCK_ASSERT(ue, MA_OWNED);
n = mbufq_flush(&ue->ue_rxq);
UE_UNLOCK(ue);
NET_EPOCH_ENTER(et);
while ((m = n) != NULL) {
n = STAILQ_NEXT(m, m_stailqpkt);
m->m_nextpkt = NULL;
ifp->if_input(ifp, m);
}
NET_EPOCH_EXIT(et);
UE_LOCK(ue);
}
/*
* USB net drivers are run by DRIVER_MODULE() thus SI_SUB_DRIVERS,
* SI_ORDER_MIDDLE. Run uether after that.
*/
DECLARE_MODULE(uether, uether_mod, SI_SUB_DRIVERS, SI_ORDER_ANY);
MODULE_VERSION(uether, 1);