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- Improve BPF locking model.

Browse Source 
Interface locks and descriptor locks are converted from mutex(9) to rwlock(9).
This greately improves performance: in most common case we need to acquire 1
reader lock instead of 2 mutexes.

- Remove filter(descriptor) (reader) lock in bpf_mtap[2]
This was suggested by glebius@. We protect filter by requesting interface
writer lock on filter change.

- Cover struct bpf_if under BPF_INTERNAL define. This permits including bpf.h
without including rwlock stuff. However, this is is temporary solution,
struct bpf_if should be made opaque for any external caller.

Found by:       Dmitrij Tejblum <tejblum@yandex-team.ru>
Sponsored by:   Yandex LLC

Reviewed by:    glebius (previous version)
Reviewed by:    silence on -net@
Approved by:    (mentor)

MFC after:      3 weeks
This commit is contained in:
Alexander V. Chernikov 2012-04-06 06:53:58 +00:00
parent 3ef51c5fb9
commit e4b3229aa5
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=233937
7 changed files with 180 additions and 123 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
sys/kern/subr_witness.c
View File

@ -563,8 +563,8 @@ static struct witness_order_list_entry order_lists[] = {
* BPF
*/
{ "bpf global lock", &lock_class_mtx_sleep },
{ "bpf interface lock", &lock_class_mtx_sleep },
{ "bpf cdev lock", &lock_class_mtx_sleep },
{ "bpf interface lock", &lock_class_rw },
{ "bpf cdev lock", &lock_class_rw },
{ NULL, NULL },
/*
* NFS server

251
sys/net/bpf.c
View File

@ -43,6 +43,8 @@ __FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
@ -66,6 +68,7 @@ __FBSDID("$FreeBSD$");
#include <sys/socket.h>
#include <net/if.h>
#define BPF_INTERNAL
#include <net/bpf.h>
#include <net/bpf_buffer.h>
#ifdef BPF_JITTER
@ -207,7 +210,7 @@ bpf_append_bytes(struct bpf_d *d, caddr_t buf, u_int offset, void *src,
u_int len)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
switch (d->bd_bufmode) {
case BPF_BUFMODE_BUFFER:
@ -227,7 +230,7 @@ bpf_append_mbuf(struct bpf_d *d, caddr_t buf, u_int offset, void *src,
u_int len)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
switch (d->bd_bufmode) {
case BPF_BUFMODE_BUFFER:
@ -249,7 +252,7 @@ static void
bpf_buf_reclaimed(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
switch (d->bd_bufmode) {
case BPF_BUFMODE_BUFFER:
@ -290,7 +293,6 @@ bpf_canfreebuf(struct bpf_d *d)
static int
bpf_canwritebuf(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
switch (d->bd_bufmode) {
@ -309,7 +311,7 @@ static void
bpf_buffull(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
switch (d->bd_bufmode) {
case BPF_BUFMODE_ZBUF:
@ -325,7 +327,7 @@ void
bpf_bufheld(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
switch (d->bd_bufmode) {
case BPF_BUFMODE_ZBUF:
@ -574,12 +576,12 @@ bpf_attachd(struct bpf_d *d, struct bpf_if *bp)
* Finally, point the driver's bpf cookie at the interface so
* it will divert packets to bpf.
*/
BPFIF_LOCK(bp);
BPFIF_WLOCK(bp);
d->bd_bif = bp;
LIST_INSERT_HEAD(&bp->bif_dlist, d, bd_next);
bpf_bpfd_cnt++;
BPFIF_UNLOCK(bp);
BPFIF_WUNLOCK(bp);
EVENTHANDLER_INVOKE(bpf_track, bp->bif_ifp, bp->bif_dlt, 1);
}
@ -594,20 +596,24 @@ bpf_detachd(struct bpf_d *d)
struct bpf_if *bp;
struct ifnet *ifp;
BPF_LOCK_ASSERT();
bp = d->bd_bif;
BPFIF_LOCK(bp);
BPFD_LOCK(d);
ifp = d->bd_bif->bif_ifp;
BPFIF_WLOCK(bp);
BPFD_WLOCK(d);
/*
* Remove d from the interface's descriptor list.
*/
LIST_REMOVE(d, bd_next);
bpf_bpfd_cnt--;
ifp = bp->bif_ifp;
d->bd_bif = NULL;
BPFD_UNLOCK(d);
BPFIF_UNLOCK(bp);
BPFD_WUNLOCK(d);
BPFIF_WUNLOCK(bp);
/* We're already protected by global lock. */
bpf_bpfd_cnt--;
EVENTHANDLER_INVOKE(bpf_track, ifp, bp->bif_dlt, 0);
@ -642,16 +648,16 @@ bpf_dtor(void *data)
{
struct bpf_d *d = data;
BPFD_LOCK(d);
BPFD_WLOCK(d);
if (d->bd_state == BPF_WAITING)
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
funsetown(&d->bd_sigio);
mtx_lock(&bpf_mtx);
BPF_LOCK();
if (d->bd_bif)
bpf_detachd(d);
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
#ifdef MAC
mac_bpfdesc_destroy(d);
#endif /* MAC */
@ -689,14 +695,14 @@ bpfopen(struct cdev *dev, int flags, int fmt, struct thread *td)
d->bd_bufmode = BPF_BUFMODE_BUFFER;
d->bd_sig = SIGIO;
d->bd_direction = BPF_D_INOUT;
d->bd_pid = td->td_proc->p_pid;
BPF_PID_REFRESH(d, td);
#ifdef MAC
mac_bpfdesc_init(d);
mac_bpfdesc_create(td->td_ucred, d);
#endif
mtx_init(&d->bd_mtx, devtoname(dev), "bpf cdev lock", MTX_DEF);
callout_init_mtx(&d->bd_callout, &d->bd_mtx, 0);
knlist_init_mtx(&d->bd_sel.si_note, &d->bd_mtx);
rw_init(&d->bd_lock, "bpf cdev lock");
callout_init_rw(&d->bd_callout, &d->bd_lock, 0);
knlist_init_rw_reader(&d->bd_sel.si_note, &d->bd_lock);
return (0);
}
@ -725,10 +731,10 @@ bpfread(struct cdev *dev, struct uio *uio, int ioflag)
non_block = ((ioflag & O_NONBLOCK) != 0);
BPFD_LOCK(d);
d->bd_pid = curthread->td_proc->p_pid;
BPFD_WLOCK(d);
BPF_PID_REFRESH_CUR(d);
if (d->bd_bufmode != BPF_BUFMODE_BUFFER) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (EOPNOTSUPP);
}
if (d->bd_state == BPF_WAITING)
@ -764,18 +770,18 @@ bpfread(struct cdev *dev, struct uio *uio, int ioflag)
* it before using it again.
*/
if (d->bd_bif == NULL) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (ENXIO);
}
if (non_block) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (EWOULDBLOCK);
}
error = msleep(d, &d->bd_mtx, PRINET|PCATCH,
error = rw_sleep(d, &d->bd_lock, PRINET|PCATCH,
"bpf", d->bd_rtout);
if (error == EINTR || error == ERESTART) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (error);
}
if (error == EWOULDBLOCK) {
@ -793,7 +799,7 @@ bpfread(struct cdev *dev, struct uio *uio, int ioflag)
break;
if (d->bd_slen == 0) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}
ROTATE_BUFFERS(d);
@ -803,7 +809,7 @@ bpfread(struct cdev *dev, struct uio *uio, int ioflag)
/*
* At this point, we know we have something in the hold slot.
*/
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
/*
* Move data from hold buffer into user space.
@ -816,12 +822,12 @@ bpfread(struct cdev *dev, struct uio *uio, int ioflag)
*/
error = bpf_uiomove(d, d->bd_hbuf, d->bd_hlen, uio);
BPFD_LOCK(d);
BPFD_WLOCK(d);
d->bd_fbuf = d->bd_hbuf;
d->bd_hbuf = NULL;
d->bd_hlen = 0;
bpf_buf_reclaimed(d);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (error);
}
@ -833,7 +839,7 @@ static __inline void
bpf_wakeup(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
if (d->bd_state == BPF_WAITING) {
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
@ -851,7 +857,7 @@ bpf_timed_out(void *arg)
{
struct bpf_d *d = (struct bpf_d *)arg;
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
if (callout_pending(&d->bd_callout) || !callout_active(&d->bd_callout))
return;
@ -866,7 +872,7 @@ static int
bpf_ready(struct bpf_d *d)
{
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
if (!bpf_canfreebuf(d) && d->bd_hlen != 0)
return (1);
@ -889,7 +895,7 @@ bpfwrite(struct cdev *dev, struct uio *uio, int ioflag)
if (error != 0)
return (error);
d->bd_pid = curthread->td_proc->p_pid;
BPF_PID_REFRESH_CUR(d);
d->bd_wcount++;
if (d->bd_bif == NULL) {
d->bd_wdcount++;
@ -937,11 +943,11 @@ bpfwrite(struct cdev *dev, struct uio *uio, int ioflag)
CURVNET_SET(ifp->if_vnet);
#ifdef MAC
BPFD_LOCK(d);
BPFD_WLOCK(d);
mac_bpfdesc_create_mbuf(d, m);
if (mc != NULL)
mac_bpfdesc_create_mbuf(d, mc);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
#endif
error = (*ifp->if_output)(ifp, m, &dst, NULL);
@ -970,7 +976,7 @@ static void
reset_d(struct bpf_d *d)
{
mtx_assert(&d->bd_mtx, MA_OWNED);
BPFD_WLOCK_ASSERT(d);
if ((d->bd_hbuf != NULL) &&
(d->bd_bufmode != BPF_BUFMODE_ZBUF || bpf_canfreebuf(d))) {
@ -1037,12 +1043,12 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
/*
* Refresh PID associated with this descriptor.
*/
BPFD_LOCK(d);
d->bd_pid = td->td_proc->p_pid;
BPFD_WLOCK(d);
BPF_PID_REFRESH(d, td);
if (d->bd_state == BPF_WAITING)
callout_stop(&d->bd_callout);
d->bd_state = BPF_IDLE;
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
if (d->bd_locked == 1) {
switch (cmd) {
@ -1108,11 +1114,11 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
{
int n;
BPFD_LOCK(d);
BPFD_WLOCK(d);
n = d->bd_slen;
if (d->bd_hbuf)
n += d->bd_hlen;
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
*(int *)addr = n;
break;
@ -1163,9 +1169,9 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
* Flush read packet buffer.
*/
case BIOCFLUSH:
BPFD_LOCK(d);
BPFD_WLOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
break;
/*
@ -1488,15 +1494,15 @@ bpfioctl(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
return (EINVAL);
}
BPFD_LOCK(d);
BPFD_WLOCK(d);
if (d->bd_sbuf != NULL || d->bd_hbuf != NULL ||
d->bd_fbuf != NULL || d->bd_bif != NULL) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
CURVNET_RESTORE();
return (EBUSY);
}
d->bd_bufmode = *(u_int *)addr;
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
break;
case BIOCGETZMAX:
@ -1556,7 +1562,12 @@ bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd)
if (fp->bf_insns == NULL) {
if (fp->bf_len != 0)
return (EINVAL);
BPFD_LOCK(d);
/*
* Protect filter change by interface lock, too.
* The same lock order is used by bpf_detachd().
*/
BPFIF_WLOCK(d->bd_bif);
BPFD_WLOCK(d);
if (wfilter)
d->bd_wfilter = NULL;
else {
@ -1567,7 +1578,8 @@ bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd)
if (cmd == BIOCSETF)
reset_d(d);
}
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
BPFIF_WUNLOCK(d->bd_bif);
if (old != NULL)
free((caddr_t)old, M_BPF);
#ifdef BPF_JITTER
@ -1584,7 +1596,12 @@ bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd)
fcode = (struct bpf_insn *)malloc(size, M_BPF, M_WAITOK);
if (copyin((caddr_t)fp->bf_insns, (caddr_t)fcode, size) == 0 &&
bpf_validate(fcode, (int)flen)) {
BPFD_LOCK(d);
/*
* Protect filter change by interface lock, too
* The same lock order is used by bpf_detachd().
*/
BPFIF_WLOCK(d->bd_bif);
BPFD_WLOCK(d);
if (wfilter)
d->bd_wfilter = fcode;
else {
@ -1595,7 +1612,8 @@ bpf_setf(struct bpf_d *d, struct bpf_program *fp, u_long cmd)
if (cmd == BIOCSETF)
reset_d(d);
}
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
BPFIF_WUNLOCK(d->bd_bif);
if (old != NULL)
free((caddr_t)old, M_BPF);
#ifdef BPF_JITTER
@ -1659,9 +1677,9 @@ bpf_setif(struct bpf_d *d, struct ifreq *ifr)
bpf_attachd(d, bp);
}
BPFD_LOCK(d);
BPFD_WLOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}
@ -1685,8 +1703,8 @@ bpfpoll(struct cdev *dev, int events, struct thread *td)
* Refresh PID associated with this descriptor.
*/
revents = events & (POLLOUT | POLLWRNORM);
BPFD_LOCK(d);
d->bd_pid = td->td_proc->p_pid;
BPFD_WLOCK(d);
BPF_PID_REFRESH(d, td);
if (events & (POLLIN | POLLRDNORM)) {
if (bpf_ready(d))
revents |= events & (POLLIN | POLLRDNORM);
@ -1700,7 +1718,7 @@ bpfpoll(struct cdev *dev, int events, struct thread *td)
}
}
}
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (revents);
}
@ -1720,12 +1738,12 @@ bpfkqfilter(struct cdev *dev, struct knote *kn)
/*
* Refresh PID associated with this descriptor.
*/
BPFD_LOCK(d);
d->bd_pid = curthread->td_proc->p_pid;
BPFD_WLOCK(d);
BPF_PID_REFRESH_CUR(d);
kn->kn_fop = &bpfread_filtops;
kn->kn_hook = d;
knlist_add(&d->bd_sel.si_note, kn, 1);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}
@ -1744,7 +1762,7 @@ filt_bpfread(struct knote *kn, long hint)
struct bpf_d *d = (struct bpf_d *)kn->kn_hook;
int ready;
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
ready = bpf_ready(d);
if (ready) {
kn->kn_data = d->bd_slen;
@ -1819,9 +1837,19 @@ bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen)
int gottime;
gottime = BPF_TSTAMP_NONE;
BPFIF_LOCK(bp);
BPFIF_RLOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
BPFD_LOCK(d);
/*
* We are not using any locks for d here because:
* 1) any filter change is protected by interface
* write lock
* 2) destroying/detaching d is protected by interface
* write lock, too
*/
/* XXX: Do not protect counter for the sake of performance. */
++d->bd_rcount;
/*
* NB: We dont call BPF_CHECK_DIRECTION() here since there is no
@ -1837,6 +1865,11 @@ bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen)
#endif
slen = bpf_filter(d->bd_rfilter, pkt, pktlen, pktlen);
if (slen != 0) {
/*
* Filter matches. Let's to acquire write lock.
*/
BPFD_WLOCK(d);
d->bd_fcount++;
if (gottime < bpf_ts_quality(d->bd_tstamp))
gottime = bpf_gettime(&bt, d->bd_tstamp, NULL);
@ -1845,10 +1878,10 @@ bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen)
#endif
catchpacket(d, pkt, pktlen, slen,
bpf_append_bytes, &bt);
BPFD_WUNLOCK(d);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
BPFIF_RUNLOCK(bp);
}
#define BPF_CHECK_DIRECTION(d, r, i) \
@ -1857,6 +1890,7 @@ bpf_tap(struct bpf_if *bp, u_char *pkt, u_int pktlen)
/*
* Incoming linkage from device drivers, when packet is in an mbuf chain.
* Locking model is explained in bpf_tap().
*/
void
bpf_mtap(struct bpf_if *bp, struct mbuf *m)
@ -1876,13 +1910,13 @@ bpf_mtap(struct bpf_if *bp, struct mbuf *m)
}
pktlen = m_length(m, NULL);
gottime = BPF_TSTAMP_NONE;
BPFIF_LOCK(bp);
BPFIF_RLOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp))
continue;
BPFD_LOCK(d);
++d->bd_rcount;
#ifdef BPF_JITTER
bf = bpf_jitter_enable != 0 ? d->bd_bfilter : NULL;
@ -1893,6 +1927,8 @@ bpf_mtap(struct bpf_if *bp, struct mbuf *m)
#endif
slen = bpf_filter(d->bd_rfilter, (u_char *)m, pktlen, 0);
if (slen != 0) {
BPFD_WLOCK(d);
d->bd_fcount++;
if (gottime < bpf_ts_quality(d->bd_tstamp))
gottime = bpf_gettime(&bt, d->bd_tstamp, m);
@ -1901,10 +1937,10 @@ bpf_mtap(struct bpf_if *bp, struct mbuf *m)
#endif
catchpacket(d, (u_char *)m, pktlen, slen,
bpf_append_mbuf, &bt);
BPFD_WUNLOCK(d);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
BPFIF_RUNLOCK(bp);
}
/*
@ -1938,14 +1974,17 @@ bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m)
pktlen += dlen;
gottime = BPF_TSTAMP_NONE;
BPFIF_LOCK(bp);
BPFIF_RLOCK(bp);
LIST_FOREACH(d, &bp->bif_dlist, bd_next) {
if (BPF_CHECK_DIRECTION(d, m->m_pkthdr.rcvif, bp->bif_ifp))
continue;
BPFD_LOCK(d);
++d->bd_rcount;
slen = bpf_filter(d->bd_rfilter, (u_char *)&mb, pktlen, 0);
if (slen != 0) {
BPFD_WLOCK(d);
d->bd_fcount++;
if (gottime < bpf_ts_quality(d->bd_tstamp))
gottime = bpf_gettime(&bt, d->bd_tstamp, m);
@ -1954,10 +1993,10 @@ bpf_mtap2(struct bpf_if *bp, void *data, u_int dlen, struct mbuf *m)
#endif
catchpacket(d, (u_char *)&mb, pktlen, slen,
bpf_append_mbuf, &bt);
BPFD_WUNLOCK(d);
}
BPFD_UNLOCK(d);
}
BPFIF_UNLOCK(bp);
BPFIF_RUNLOCK(bp);
}
#undef BPF_CHECK_DIRECTION
@ -2049,7 +2088,7 @@ catchpacket(struct bpf_d *d, u_char *pkt, u_int pktlen, u_int snaplen,
int do_timestamp;
int tstype;
BPFD_LOCK_ASSERT(d);
BPFD_WLOCK_ASSERT(d);
/*
* Detect whether user space has released a buffer back to us, and if
@ -2196,7 +2235,7 @@ bpf_freed(struct bpf_d *d)
}
if (d->bd_wfilter != NULL)
free((caddr_t)d->bd_wfilter, M_BPF);
mtx_destroy(&d->bd_mtx);
rw_destroy(&d->bd_lock);
}
/*
@ -2228,13 +2267,13 @@ bpfattach2(struct ifnet *ifp, u_int dlt, u_int hdrlen, struct bpf_if **driverp)
LIST_INIT(&bp->bif_dlist);
bp->bif_ifp = ifp;
bp->bif_dlt = dlt;
mtx_init(&bp->bif_mtx, "bpf interface lock", NULL, MTX_DEF);
rw_init(&bp->bif_lock, "bpf interface lock");
KASSERT(*driverp == NULL, ("bpfattach2: driverp already initialized"));
*driverp = bp;
mtx_lock(&bpf_mtx);
BPF_LOCK();
LIST_INSERT_HEAD(&bpf_iflist, bp, bif_next);
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
bp->bif_hdrlen = hdrlen;
@ -2261,14 +2300,14 @@ bpfdetach(struct ifnet *ifp)
/* Find all bpf_if struct's which reference ifp and detach them. */
do {
mtx_lock(&bpf_mtx);
BPF_LOCK();
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (ifp == bp->bif_ifp)
break;
}
if (bp != NULL)
LIST_REMOVE(bp, bif_next);
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
if (bp != NULL) {
#ifdef INVARIANTS
@ -2276,11 +2315,11 @@ bpfdetach(struct ifnet *ifp)
#endif
while ((d = LIST_FIRST(&bp->bif_dlist)) != NULL) {
bpf_detachd(d);
BPFD_LOCK(d);
BPFD_WLOCK(d);
bpf_wakeup(d);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
}
mtx_destroy(&bp->bif_mtx);
rw_destroy(&bp->bif_lock);
free(bp, M_BPF);
}
} while (bp != NULL);
@ -2304,13 +2343,13 @@ bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl)
ifp = d->bd_bif->bif_ifp;
n = 0;
error = 0;
mtx_lock(&bpf_mtx);
BPF_LOCK();
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (bp->bif_ifp != ifp)
continue;
if (bfl->bfl_list != NULL) {
if (n >= bfl->bfl_len) {
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
return (ENOMEM);
}
error = copyout(&bp->bif_dlt,
@ -2318,7 +2357,7 @@ bpf_getdltlist(struct bpf_d *d, struct bpf_dltlist *bfl)
}
n++;
}
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
bfl->bfl_len = n;
return (error);
}
@ -2336,19 +2375,19 @@ bpf_setdlt(struct bpf_d *d, u_int dlt)
if (d->bd_bif->bif_dlt == dlt)
return (0);
ifp = d->bd_bif->bif_ifp;
mtx_lock(&bpf_mtx);
BPF_LOCK();
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
if (bp->bif_ifp == ifp && bp->bif_dlt == dlt)
break;
}
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
if (bp != NULL) {
opromisc = d->bd_promisc;
bpf_detachd(d);
bpf_attachd(d, bp);
BPFD_LOCK(d);
BPFD_WLOCK(d);
reset_d(d);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
if (opromisc) {
error = ifpromisc(bp->bif_ifp, 1);
if (error)
@ -2386,22 +2425,22 @@ bpf_zero_counters(void)
struct bpf_if *bp;
struct bpf_d *bd;
mtx_lock(&bpf_mtx);
BPF_LOCK();
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
BPFIF_LOCK(bp);
BPFIF_RLOCK(bp);
LIST_FOREACH(bd, &bp->bif_dlist, bd_next) {
BPFD_LOCK(bd);
BPFD_WLOCK(bd);
bd->bd_rcount = 0;
bd->bd_dcount = 0;
bd->bd_fcount = 0;
bd->bd_wcount = 0;
bd->bd_wfcount = 0;
bd->bd_zcopy = 0;
BPFD_UNLOCK(bd);
BPFD_WUNLOCK(bd);
}
BPFIF_UNLOCK(bp);
BPFIF_RUNLOCK(bp);
}
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
}
static void
@ -2472,24 +2511,24 @@ bpf_stats_sysctl(SYSCTL_HANDLER_ARGS)
if (bpf_bpfd_cnt == 0)
return (SYSCTL_OUT(req, 0, 0));
xbdbuf = malloc(req->oldlen, M_BPF, M_WAITOK);
mtx_lock(&bpf_mtx);
BPF_LOCK();
if (req->oldlen < (bpf_bpfd_cnt * sizeof(*xbd))) {
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
free(xbdbuf, M_BPF);
return (ENOMEM);
}
index = 0;
LIST_FOREACH(bp, &bpf_iflist, bif_next) {
BPFIF_LOCK(bp);
BPFIF_RLOCK(bp);
LIST_FOREACH(bd, &bp->bif_dlist, bd_next) {
xbd = &xbdbuf[index++];
BPFD_LOCK(bd);
BPFD_RLOCK(bd);
bpfstats_fill_xbpf(xbd, bd);
BPFD_UNLOCK(bd);
BPFD_RUNLOCK(bd);
}
BPFIF_UNLOCK(bp);
BPFIF_RUNLOCK(bp);
}
mtx_unlock(&bpf_mtx);
BPF_UNLOCK();
error = SYSCTL_OUT(req, xbdbuf, index * sizeof(*xbd));
free(xbdbuf, M_BPF);
return (error);

7
sys/net/bpf.h
View File

@ -1092,14 +1092,19 @@ SYSCTL_DECL(_net_bpf);
/*
* Descriptor associated with each attached hardware interface.
* FIXME: this structure is exposed to external callers to speed up
* bpf_peers_present() call. However we cover all fields not needed by
* this function via BPF_INTERNAL define
*/
struct bpf_if {
LIST_ENTRY(bpf_if) bif_next; /* list of all interfaces */
LIST_HEAD(, bpf_d) bif_dlist; /* descriptor list */
#ifdef BPF_INTERNAL
u_int bif_dlt; /* link layer type */
u_int bif_hdrlen; /* length of link header */
struct ifnet *bif_ifp; /* corresponding interface */
struct mtx bif_mtx; /* mutex for interface */
struct rwlock bif_lock; /* interface lock */
#endif
};
void bpf_bufheld(struct bpf_d *d);

6
sys/net/bpf_buffer.c
View File

@ -184,9 +184,9 @@ bpf_buffer_ioctl_sblen(struct bpf_d *d, u_int *i)
{
u_int size;
BPFD_LOCK(d);
BPFD_WLOCK(d);
if (d->bd_bif != NULL) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (EINVAL);
}
size = *i;
@ -195,7 +195,7 @@ bpf_buffer_ioctl_sblen(struct bpf_d *d, u_int *i)
else if (size < BPF_MINBUFSIZE)
*i = size = BPF_MINBUFSIZE;
d->bd_bufsize = size;
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}

10
sys/net/bpf_zerocopy.c
View File

@ -515,14 +515,14 @@ bpf_zerocopy_ioctl_rotzbuf(struct thread *td, struct bpf_d *d,
struct zbuf *bzh;
bzero(bz, sizeof(*bz));
BPFD_LOCK(d);
BPFD_WLOCK(d);
if (d->bd_hbuf == NULL && d->bd_slen != 0) {
ROTATE_BUFFERS(d);
bzh = (struct zbuf *)d->bd_hbuf;
bz->bz_bufa = (void *)bzh->zb_uaddr;
bz->bz_buflen = d->bd_hlen;
}
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}
@ -570,10 +570,10 @@ bpf_zerocopy_ioctl_setzbuf(struct thread *td, struct bpf_d *d,
* We only allow buffers to be installed once, so atomically check
* that no buffers are currently installed and install new buffers.
*/
BPFD_LOCK(d);
BPFD_WLOCK(d);
if (d->bd_hbuf != NULL || d->bd_sbuf != NULL || d->bd_fbuf != NULL ||
d->bd_bif != NULL) {
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
zbuf_free(zba);
zbuf_free(zbb);
return (EINVAL);
@ -593,6 +593,6 @@ bpf_zerocopy_ioctl_setzbuf(struct thread *td, struct bpf_d *d,
* shared management region.
*/
d->bd_bufsize = bz->bz_buflen - sizeof(struct bpf_zbuf_header);
BPFD_UNLOCK(d);
BPFD_WUNLOCK(d);
return (0);
}

23
sys/net/bpfdesc.h
View File

@ -87,7 +87,7 @@ struct bpf_d {
int bd_sig; /* signal to send upon packet reception */
struct sigio * bd_sigio; /* information for async I/O */
struct selinfo bd_sel; /* bsd select info */
struct mtx bd_mtx; /* mutex for this descriptor */
struct rwlock bd_lock; /* per-descriptor lock */
struct callout bd_callout; /* for BPF timeouts with select */
struct label *bd_label; /* MAC label for descriptor */
u_int64_t bd_fcount; /* number of packets which matched filter */
@ -106,10 +106,19 @@ struct bpf_d {
#define BPF_WAITING 1 /* waiting for read timeout in select */
#define BPF_TIMED_OUT 2 /* read timeout has expired in select */
#define BPFD_LOCK(bd) mtx_lock(&(bd)->bd_mtx)
#define BPFD_UNLOCK(bd) mtx_unlock(&(bd)->bd_mtx)
#define BPFD_LOCK_ASSERT(bd) mtx_assert(&(bd)->bd_mtx, MA_OWNED)
#define BPFD_RLOCK(bd) rw_rlock(&(bd)->bd_lock)
#define BPFD_RUNLOCK(bd) rw_runlock(&(bd)->bd_lock)
#define BPFD_WLOCK(bd) rw_wlock(&(bd)->bd_lock)
#define BPFD_WUNLOCK(bd) rw_wunlock(&(bd)->bd_lock)
#define BPFD_WLOCK_ASSERT(bd) rw_assert(&(bd)->bd_lock, RA_WLOCKED)
#define BPFD_LOCK_ASSERT(bd) rw_assert(&(bd)->bd_lock, RA_LOCKED)
#define BPF_PID_REFRESH(bd, td) (bd)->bd_pid = (td)->td_proc->p_pid
#define BPF_PID_REFRESH_CUR(bd) (bd)->bd_pid = curthread->td_proc->p_pid
#define BPF_LOCK() mtx_lock(&bpf_mtx)
#define BPF_UNLOCK() mtx_unlock(&bpf_mtx)
#define BPF_LOCK_ASSERT() mtx_assert(&bpf_mtx, MA_OWNED)
/*
* External representation of the bpf descriptor
*/
@ -144,7 +153,9 @@ struct xbpf_d {
u_int64_t bd_spare[4];
};
#define BPFIF_LOCK(bif) mtx_lock(&(bif)->bif_mtx)
#define BPFIF_UNLOCK(bif) mtx_unlock(&(bif)->bif_mtx)
#define BPFIF_RLOCK(bif) rw_rlock(&(bif)->bif_lock)
#define BPFIF_RUNLOCK(bif) rw_runlock(&(bif)->bif_lock)
#define BPFIF_WLOCK(bif) rw_wlock(&(bif)->bif_lock)
#define BPFIF_WUNLOCK(bif) rw_wunlock(&(bif)->bif_lock)
#endif

2
sys/security/mac/mac_net.c
View File

@ -319,6 +319,7 @@ mac_bpfdesc_create_mbuf(struct bpf_d *d, struct mbuf *m)
{
struct label *label;
/* Assume reader lock is enough. */
BPFD_LOCK_ASSERT(d);
if (mac_policy_count == 0)
@ -354,6 +355,7 @@ mac_bpfdesc_check_receive(struct bpf_d *d, struct ifnet *ifp)
{
int error;
/* Assume reader lock is enough. */
BPFD_LOCK_ASSERT(d);
if (mac_policy_count == 0)