1
0
mirror of https://git.FreeBSD.org/src.git synced 2024-12-24 11:29:10 +00:00
freebsd/sys/net/ifq.h
Marcel Moolenaar 62d76917b8 Introduce a procedural interface to the ifnet structure. The new
interface allows the ifnet structure to be defined as an opaque
type in NIC drivers.  This then allows the ifnet structure to be
changed without a need to change or recompile NIC drivers.

Put differently, NIC drivers can be written and compiled once and
be used with different network stack implementations, provided of
course that those network stack implementations have an API and
ABI compatible interface.

This commit introduces the 'if_t' type to replace 'struct ifnet *'
as the type of a network interface. The 'if_t' type is defined as
'void *' to enable the compiler to perform type conversion to
'struct ifnet *' and vice versa where needed and without warnings.
The functions that implement the API are the only functions that
need to have an explicit cast.

The MII code has been converted to use the driver API to avoid
unnecessary code churn. Code churn comes from having to work with
both converted and unconverted drivers in correlation with having
callback functions that take an interface. By converting the MII
code first, the callback functions can be defined so that the
compiler will perform the typecasts automatically.

As soon as all drivers have been converted, the if_t type can be
redefined as needed and the API functions can be fix to not need
an explicit cast.

The immediate benefactors of this change are:
1.  Juniper Networks - The network stack implementation in Junos
    is entirely different from FreeBSD's one and this change
    allows Juniper to build "stock" NIC drivers that can be used
    in combination with both the FreeBSD and Junos stacks.
2.  FreeBSD - This change opens the door towards changing ifnet
    and implementing new features and optimizations in the network
    stack without it requiring a change in the many NIC drivers
    FreeBSD has.

Submitted by:	Anuranjan Shukla <anshukla@juniper.net>
Reviewed by:	glebius@
Obtained from:	Juniper Networks, Inc.
2014-06-02 17:54:39 +00:00

495 lines
12 KiB
C

/*-
* Copyright (c) 1982, 1986, 1989, 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 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.
* 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 DISCLAIMED. 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.h 8.1 (Berkeley) 6/10/93
* $FreeBSD$
*/
#ifndef _NET_IFQ_H_
#define _NET_IFQ_H_
#ifdef _KERNEL
#include <sys/mbuf.h> /* ifqueue only? */
#include <sys/buf_ring.h>
#include <net/vnet.h>
#endif /* _KERNEL */
#include <sys/lock.h> /* XXX */
#include <sys/mutex.h> /* struct ifqueue */
#define IF_DUNIT_NONE -1
#include <altq/if_altq.h>
/*
* Structure defining a queue for a network interface.
*/
struct ifqueue {
struct mbuf *ifq_head;
struct mbuf *ifq_tail;
int ifq_len;
int ifq_maxlen;
int ifq_drops;
struct mtx ifq_mtx;
};
#ifdef _KERNEL
/*
* Output queues (ifp->if_snd) and slow device input queues (*ifp->if_slowq)
* are queues of messages stored on ifqueue structures
* (defined above). Entries are added to and deleted from these structures
* by these macros.
*/
#define IF_LOCK(ifq) mtx_lock(&(ifq)->ifq_mtx)
#define IF_UNLOCK(ifq) mtx_unlock(&(ifq)->ifq_mtx)
#define IF_LOCK_ASSERT(ifq) mtx_assert(&(ifq)->ifq_mtx, MA_OWNED)
#define _IF_QFULL(ifq) ((ifq)->ifq_len >= (ifq)->ifq_maxlen)
#define _IF_DROP(ifq) ((ifq)->ifq_drops++)
#define _IF_QLEN(ifq) ((ifq)->ifq_len)
#define _IF_ENQUEUE(ifq, m) do { \
(m)->m_nextpkt = NULL; \
if ((ifq)->ifq_tail == NULL) \
(ifq)->ifq_head = m; \
else \
(ifq)->ifq_tail->m_nextpkt = m; \
(ifq)->ifq_tail = m; \
(ifq)->ifq_len++; \
} while (0)
#define IF_ENQUEUE(ifq, m) do { \
IF_LOCK(ifq); \
_IF_ENQUEUE(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define _IF_PREPEND(ifq, m) do { \
(m)->m_nextpkt = (ifq)->ifq_head; \
if ((ifq)->ifq_tail == NULL) \
(ifq)->ifq_tail = (m); \
(ifq)->ifq_head = (m); \
(ifq)->ifq_len++; \
} while (0)
#define IF_PREPEND(ifq, m) do { \
IF_LOCK(ifq); \
_IF_PREPEND(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define _IF_DEQUEUE(ifq, m) do { \
(m) = (ifq)->ifq_head; \
if (m) { \
if (((ifq)->ifq_head = (m)->m_nextpkt) == NULL) \
(ifq)->ifq_tail = NULL; \
(m)->m_nextpkt = NULL; \
(ifq)->ifq_len--; \
} \
} while (0)
#define IF_DEQUEUE(ifq, m) do { \
IF_LOCK(ifq); \
_IF_DEQUEUE(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define _IF_DEQUEUE_ALL(ifq, m) do { \
(m) = (ifq)->ifq_head; \
(ifq)->ifq_head = (ifq)->ifq_tail = NULL; \
(ifq)->ifq_len = 0; \
} while (0)
#define IF_DEQUEUE_ALL(ifq, m) do { \
IF_LOCK(ifq); \
_IF_DEQUEUE_ALL(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define _IF_POLL(ifq, m) ((m) = (ifq)->ifq_head)
#define IF_POLL(ifq, m) _IF_POLL(ifq, m)
#define _IF_DRAIN(ifq) do { \
struct mbuf *m; \
for (;;) { \
_IF_DEQUEUE(ifq, m); \
if (m == NULL) \
break; \
m_freem(m); \
} \
} while (0)
#define IF_DRAIN(ifq) do { \
IF_LOCK(ifq); \
_IF_DRAIN(ifq); \
IF_UNLOCK(ifq); \
} while(0)
int if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp,
int adjust);
#define IF_HANDOFF(ifq, m, ifp) \
if_handoff((struct ifqueue *)ifq, m, ifp, 0)
#define IF_HANDOFF_ADJ(ifq, m, ifp, adj) \
if_handoff((struct ifqueue *)ifq, m, ifp, adj)
void if_start(struct ifnet *);
#define IFQ_ENQUEUE(ifq, m, err) \
do { \
IF_LOCK(ifq); \
if (ALTQ_IS_ENABLED(ifq)) \
ALTQ_ENQUEUE(ifq, m, NULL, err); \
else { \
if (_IF_QFULL(ifq)) { \
m_freem(m); \
(err) = ENOBUFS; \
} else { \
_IF_ENQUEUE(ifq, m); \
(err) = 0; \
} \
} \
if (err) \
(ifq)->ifq_drops++; \
IF_UNLOCK(ifq); \
} while (0)
#define IFQ_DEQUEUE_NOLOCK(ifq, m) \
do { \
if (TBR_IS_ENABLED(ifq)) \
(m) = tbr_dequeue_ptr(ifq, ALTDQ_REMOVE); \
else if (ALTQ_IS_ENABLED(ifq)) \
ALTQ_DEQUEUE(ifq, m); \
else \
_IF_DEQUEUE(ifq, m); \
} while (0)
#define IFQ_DEQUEUE(ifq, m) \
do { \
IF_LOCK(ifq); \
IFQ_DEQUEUE_NOLOCK(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define IFQ_POLL_NOLOCK(ifq, m) \
do { \
if (TBR_IS_ENABLED(ifq)) \
(m) = tbr_dequeue_ptr(ifq, ALTDQ_POLL); \
else if (ALTQ_IS_ENABLED(ifq)) \
ALTQ_POLL(ifq, m); \
else \
_IF_POLL(ifq, m); \
} while (0)
#define IFQ_POLL(ifq, m) \
do { \
IF_LOCK(ifq); \
IFQ_POLL_NOLOCK(ifq, m); \
IF_UNLOCK(ifq); \
} while (0)
#define IFQ_PURGE_NOLOCK(ifq) \
do { \
if (ALTQ_IS_ENABLED(ifq)) { \
ALTQ_PURGE(ifq); \
} else \
_IF_DRAIN(ifq); \
} while (0)
#define IFQ_PURGE(ifq) \
do { \
IF_LOCK(ifq); \
IFQ_PURGE_NOLOCK(ifq); \
IF_UNLOCK(ifq); \
} while (0)
#define IFQ_SET_READY(ifq) \
do { ((ifq)->altq_flags |= ALTQF_READY); } while (0)
#define IFQ_LOCK(ifq) IF_LOCK(ifq)
#define IFQ_UNLOCK(ifq) IF_UNLOCK(ifq)
#define IFQ_LOCK_ASSERT(ifq) IF_LOCK_ASSERT(ifq)
#define IFQ_IS_EMPTY(ifq) ((ifq)->ifq_len == 0)
#define IFQ_INC_LEN(ifq) ((ifq)->ifq_len++)
#define IFQ_DEC_LEN(ifq) (--(ifq)->ifq_len)
#define IFQ_INC_DROPS(ifq) ((ifq)->ifq_drops++)
#define IFQ_SET_MAXLEN(ifq, len) ((ifq)->ifq_maxlen = (len))
/*
* The IFF_DRV_OACTIVE test should really occur in the device driver, not in
* the handoff logic, as that flag is locked by the device driver.
*/
#define IFQ_HANDOFF_ADJ(ifp, m, adj, err) \
do { \
int len; \
short mflags; \
\
len = (m)->m_pkthdr.len; \
mflags = (m)->m_flags; \
IFQ_ENQUEUE(&(ifp)->if_snd, m, err); \
if ((err) == 0) { \
(ifp)->if_obytes += len + (adj); \
if (mflags & M_MCAST) \
(ifp)->if_omcasts++; \
if (((ifp)->if_drv_flags & IFF_DRV_OACTIVE) == 0) \
if_start(ifp); \
} \
} while (0)
#define IFQ_HANDOFF(ifp, m, err) \
IFQ_HANDOFF_ADJ(ifp, m, 0, err)
#define IFQ_DRV_DEQUEUE(ifq, m) \
do { \
(m) = (ifq)->ifq_drv_head; \
if (m) { \
if (((ifq)->ifq_drv_head = (m)->m_nextpkt) == NULL) \
(ifq)->ifq_drv_tail = NULL; \
(m)->m_nextpkt = NULL; \
(ifq)->ifq_drv_len--; \
} else { \
IFQ_LOCK(ifq); \
IFQ_DEQUEUE_NOLOCK(ifq, m); \
while ((ifq)->ifq_drv_len < (ifq)->ifq_drv_maxlen) { \
struct mbuf *m0; \
IFQ_DEQUEUE_NOLOCK(ifq, m0); \
if (m0 == NULL) \
break; \
m0->m_nextpkt = NULL; \
if ((ifq)->ifq_drv_tail == NULL) \
(ifq)->ifq_drv_head = m0; \
else \
(ifq)->ifq_drv_tail->m_nextpkt = m0; \
(ifq)->ifq_drv_tail = m0; \
(ifq)->ifq_drv_len++; \
} \
IFQ_UNLOCK(ifq); \
} \
} while (0)
#define IFQ_DRV_PREPEND(ifq, m) \
do { \
(m)->m_nextpkt = (ifq)->ifq_drv_head; \
if ((ifq)->ifq_drv_tail == NULL) \
(ifq)->ifq_drv_tail = (m); \
(ifq)->ifq_drv_head = (m); \
(ifq)->ifq_drv_len++; \
} while (0)
#define IFQ_DRV_IS_EMPTY(ifq) \
(((ifq)->ifq_drv_len == 0) && ((ifq)->ifq_len == 0))
#define IFQ_DRV_PURGE(ifq) \
do { \
struct mbuf *m, *n = (ifq)->ifq_drv_head; \
while((m = n) != NULL) { \
n = m->m_nextpkt; \
m_freem(m); \
} \
(ifq)->ifq_drv_head = (ifq)->ifq_drv_tail = NULL; \
(ifq)->ifq_drv_len = 0; \
IFQ_PURGE(ifq); \
} while (0)
static __inline int
drbr_enqueue(struct ifnet *ifp, struct buf_ring *br, struct mbuf *m)
{
int error = 0;
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
IFQ_ENQUEUE(&ifp->if_snd, m, error);
return (error);
}
#endif
error = buf_ring_enqueue(br, m);
if (error)
m_freem(m);
return (error);
}
static __inline void
drbr_putback(struct ifnet *ifp, struct buf_ring *br, struct mbuf *new)
{
/*
* The top of the list needs to be swapped
* for this one.
*/
#ifdef ALTQ
if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) {
/*
* Peek in altq case dequeued it
* so put it back.
*/
IFQ_DRV_PREPEND(&ifp->if_snd, new);
return;
}
#endif
buf_ring_putback_sc(br, new);
}
static __inline struct mbuf *
drbr_peek(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
struct mbuf *m;
if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) {
/*
* Pull it off like a dequeue
* since drbr_advance() does nothing
* for altq and drbr_putback() will
* use the old prepend function.
*/
IFQ_DEQUEUE(&ifp->if_snd, m);
return (m);
}
#endif
return(buf_ring_peek(br));
}
static __inline void
drbr_flush(struct ifnet *ifp, struct buf_ring *br)
{
struct mbuf *m;
#ifdef ALTQ
if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd))
IFQ_PURGE(&ifp->if_snd);
#endif
while ((m = buf_ring_dequeue_sc(br)) != NULL)
m_freem(m);
}
static __inline void
drbr_free(struct buf_ring *br, struct malloc_type *type)
{
drbr_flush(NULL, br);
buf_ring_free(br, type);
}
static __inline struct mbuf *
drbr_dequeue(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
struct mbuf *m;
if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd)) {
IFQ_DEQUEUE(&ifp->if_snd, m);
return (m);
}
#endif
return (buf_ring_dequeue_sc(br));
}
static __inline void
drbr_advance(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
/* Nothing to do here since peek dequeues in altq case */
if (ifp != NULL && ALTQ_IS_ENABLED(&ifp->if_snd))
return;
#endif
return (buf_ring_advance_sc(br));
}
static __inline struct mbuf *
drbr_dequeue_cond(struct ifnet *ifp, struct buf_ring *br,
int (*func) (struct mbuf *, void *), void *arg)
{
struct mbuf *m;
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd)) {
IFQ_LOCK(&ifp->if_snd);
IFQ_POLL_NOLOCK(&ifp->if_snd, m);
if (m != NULL && func(m, arg) == 0) {
IFQ_UNLOCK(&ifp->if_snd);
return (NULL);
}
IFQ_DEQUEUE_NOLOCK(&ifp->if_snd, m);
IFQ_UNLOCK(&ifp->if_snd);
return (m);
}
#endif
m = buf_ring_peek(br);
if (m == NULL || func(m, arg) == 0)
return (NULL);
return (buf_ring_dequeue_sc(br));
}
static __inline int
drbr_empty(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd))
return (IFQ_IS_EMPTY(&ifp->if_snd));
#endif
return (buf_ring_empty(br));
}
static __inline int
drbr_needs_enqueue(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd))
return (1);
#endif
return (!buf_ring_empty(br));
}
static __inline int
drbr_inuse(struct ifnet *ifp, struct buf_ring *br)
{
#ifdef ALTQ
if (ALTQ_IS_ENABLED(&ifp->if_snd))
return (ifp->if_snd.ifq_len);
#endif
return (buf_ring_count(br));
}
extern int ifqmaxlen;
void if_qflush(struct ifnet *);
void ifq_init(struct ifaltq *, struct ifnet *ifp);
void ifq_delete(struct ifaltq *);
#ifdef DEVICE_POLLING
enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS };
typedef int poll_handler_t(struct ifnet *ifp, enum poll_cmd cmd, int count);
int ether_poll_register(poll_handler_t *h, struct ifnet *ifp);
int ether_poll_deregister(struct ifnet *ifp);
/* The following should be temporary, till all drivers use the driver API */
typedef int poll_handler_drv_t(if_t ifh, enum poll_cmd cmd, int count);
int ether_poll_register_drv(poll_handler_drv_t *h, if_t ifh);
int ether_poll_deregister_drv(if_t ifh);
#endif /* DEVICE_POLLING */
#endif /* _KERNEL */
#endif /* !_NET_IFQ_H_ */