freebsd-dev/sys/net/if_var.h
Luigi Rizzo e4fc250c15 Device Polling code for -current.
Non-SMP, i386-only, no polling in the idle loop at the moment.

To use this code you must compile a kernel with

        options DEVICE_POLLING

and at runtime enable polling with

        sysctl kern.polling.enable=1

The percentage of CPU reserved to userland can be set with

        sysctl kern.polling.user_frac=NN (default is 50)

while the remainder is used by polling device drivers and netisr's.
These are the only two variables that you should need to touch. There
are a few more parameters in kern.polling but the default values
are adequate for all purposes. See the code in kern_poll.c for
more details on them.

Polling in the idle loop will be implemented shortly by introducing
a kernel thread which does the job. Until then, the amount of CPU
dedicated to polling will never exceed (100-user_frac).
The equivalent (actually, better) code for -stable is at

	http://info.iet.unipi.it/~luigi/polling/

and also supports polling in the idle loop.

NOTE to Alpha developers:
There is really nothing in this code that is i386-specific.
If you move the 2 lines supporting the new option from
sys/conf/{files,options}.i386 to sys/conf/{files,options} I am
pretty sure that this should work on the Alpha as well, just that
I do not have a suitable test box to try it. If someone feels like
trying it, I would appreciate it.

NOTE to other developers:
sure some things could be done better, and as always I am open to
constructive criticism, which a few of you have already given and
I greatly appreciated.
However, before proposing radical architectural changes, please
take some time to possibly try out this code, or at the very least
read the comments in kern_poll.c, especially re. the reason why I
am using a soft netisr and cannot (I believe) replace it with a
simple timeout.

Quick description of files touched by this commit:

sys/conf/files.i386
        new file kern/kern_poll.c
sys/conf/options.i386
        new option
sys/i386/i386/trap.c
        poll in trap (disabled by default)
sys/kern/kern_clock.c
        initialization and hardclock hooks.
sys/kern/kern_intr.c
        minor swi_net changes
sys/kern/kern_poll.c
        the bulk of the code.
sys/net/if.h
        new flag
sys/net/if_var.h
        declaration for functions used in device drivers.
sys/net/netisr.h
        NETISR_POLL
sys/dev/fxp/if_fxp.c
sys/dev/fxp/if_fxpvar.h
sys/pci/if_dc.c
sys/pci/if_dcreg.h
sys/pci/if_sis.c
sys/pci/if_sisreg.h
        device driver modifications
2001-12-14 17:56:12 +00:00

474 lines
16 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 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_IF_VAR_H_
#define _NET_IF_VAR_H_
/*
* Structures defining a network interface, providing a packet
* transport mechanism (ala level 0 of the PUP protocols).
*
* Each interface accepts output datagrams of a specified maximum
* length, and provides higher level routines with input datagrams
* received from its medium.
*
* Output occurs when the routine if_output is called, with three parameters:
* (*ifp->if_output)(ifp, m, dst, rt)
* Here m is the mbuf chain to be sent and dst is the destination address.
* The output routine encapsulates the supplied datagram if necessary,
* and then transmits it on its medium.
*
* On input, each interface unwraps the data received by it, and either
* places it on the input queue of a internetwork datagram routine
* and posts the associated software interrupt, or passes the datagram to a raw
* packet input routine.
*
* Routines exist for locating interfaces by their addresses
* or for locating a interface on a certain network, as well as more general
* routing and gateway routines maintaining information used to locate
* interfaces. These routines live in the files if.c and route.c
*/
#ifdef __STDC__
/*
* Forward structure declarations for function prototypes [sic].
*/
struct mbuf;
struct thread;
struct rtentry;
struct rt_addrinfo;
struct socket;
struct ether_header;
#endif
#include <sys/queue.h> /* get TAILQ macros */
#ifdef _KERNEL
#include <sys/mbuf.h>
#include <sys/systm.h> /* XXX */
#endif /* _KERNEL */
#include <sys/lock.h> /* XXX */
#include <sys/mutex.h> /* XXX */
#include <sys/event.h> /* XXX */
TAILQ_HEAD(ifnethead, ifnet); /* we use TAILQs so that the order of */
TAILQ_HEAD(ifaddrhead, ifaddr); /* instantiation is preserved in the list */
TAILQ_HEAD(ifprefixhead, ifprefix);
TAILQ_HEAD(ifmultihead, ifmultiaddr);
/*
* 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;
};
/*
* Structure defining a network interface.
*
* (Would like to call this struct ``if'', but C isn't PL/1.)
*/
/*
* NB: For FreeBSD, it is assumed that each NIC driver's softc starts with
* one of these structures, typically held within an arpcom structure.
*
* struct <foo>_softc {
* struct arpcom {
* struct ifnet ac_if;
* ...
* } <arpcom> ;
* ...
* };
*
* The assumption is used in a number of places, including many
* files in sys/net, device drivers, and sys/dev/mii.c:miibus_attach().
*
* Unfortunately devices' softc are opaque, so we depend on this layout
* to locate the struct ifnet from the softc in the generic code.
*
*/
struct ifnet {
void *if_softc; /* pointer to driver state */
char *if_name; /* name, e.g. ``en'' or ``lo'' */
TAILQ_ENTRY(ifnet) if_link; /* all struct ifnets are chained */
struct ifaddrhead if_addrhead; /* linked list of addresses per if */
struct klist if_klist; /* events attached to this if */
int if_pcount; /* number of promiscuous listeners */
struct bpf_if *if_bpf; /* packet filter structure */
u_short if_index; /* numeric abbreviation for this if */
short if_unit; /* sub-unit for lower level driver */
short if_timer; /* time 'til if_watchdog called */
short if_flags; /* up/down, broadcast, etc. */
int if_capabilities; /* interface capabilities */
int if_capenable; /* enabled features */
int if_ipending; /* interrupts pending */
void *if_linkmib; /* link-type-specific MIB data */
size_t if_linkmiblen; /* length of above data */
struct if_data if_data;
struct ifmultihead if_multiaddrs; /* multicast addresses configured */
int if_amcount; /* number of all-multicast requests */
/* procedure handles */
int (*if_output) /* output routine (enqueue) */
__P((struct ifnet *, struct mbuf *, struct sockaddr *,
struct rtentry *));
void (*if_start) /* initiate output routine */
__P((struct ifnet *));
int (*if_done) /* output complete routine */
__P((struct ifnet *)); /* (XXX not used; fake prototype) */
int (*if_ioctl) /* ioctl routine */
__P((struct ifnet *, u_long, caddr_t));
void (*if_watchdog) /* timer routine */
__P((struct ifnet *));
int (*if_poll_recv) /* polled receive routine */
__P((struct ifnet *, int *));
int (*if_poll_xmit) /* polled transmit routine */
__P((struct ifnet *, int *));
void (*if_poll_intren) /* polled interrupt reenable routine */
__P((struct ifnet *));
void (*if_poll_slowinput) /* input routine for slow devices */
__P((struct ifnet *, struct mbuf *));
void (*if_init) /* Init routine */
__P((void *));
int (*if_resolvemulti) /* validate/resolve multicast */
__P((struct ifnet *, struct sockaddr **, struct sockaddr *));
struct ifqueue if_snd; /* output queue */
struct ifqueue *if_poll_slowq; /* input queue for slow devices */
struct ifprefixhead if_prefixhead; /* list of prefixes per if */
u_int8_t *if_broadcastaddr; /* linklevel broadcast bytestring */
};
typedef void if_init_f_t __P((void *));
#define if_mtu if_data.ifi_mtu
#define if_type if_data.ifi_type
#define if_physical if_data.ifi_physical
#define if_addrlen if_data.ifi_addrlen
#define if_hdrlen if_data.ifi_hdrlen
#define if_metric if_data.ifi_metric
#define if_baudrate if_data.ifi_baudrate
#define if_hwassist if_data.ifi_hwassist
#define if_ipackets if_data.ifi_ipackets
#define if_ierrors if_data.ifi_ierrors
#define if_opackets if_data.ifi_opackets
#define if_oerrors if_data.ifi_oerrors
#define if_collisions if_data.ifi_collisions
#define if_ibytes if_data.ifi_ibytes
#define if_obytes if_data.ifi_obytes
#define if_imcasts if_data.ifi_imcasts
#define if_omcasts if_data.ifi_omcasts
#define if_iqdrops if_data.ifi_iqdrops
#define if_noproto if_data.ifi_noproto
#define if_lastchange if_data.ifi_lastchange
#define if_recvquota if_data.ifi_recvquota
#define if_xmitquota if_data.ifi_xmitquota
#define if_rawoutput(if, m, sa) if_output(if, m, sa, (struct rtentry *)0)
/* for compatibility with other BSDs */
#define if_addrlist if_addrhead
#define if_list if_link
/*
* Bit values in if_ipending
*/
#define IFI_RECV 1 /* I want to receive */
#define IFI_XMIT 2 /* I want to transmit */
/*
* 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, which should be called with ipl raised to splimp().
*/
#define IF_LOCK(ifq) mtx_lock(&(ifq)->ifq_mtx)
#define IF_UNLOCK(ifq) mtx_unlock(&(ifq)->ifq_mtx)
#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) == 0) \
(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_DRAIN(ifq) do { \
struct mbuf *m; \
IF_LOCK(ifq); \
for (;;) { \
_IF_DEQUEUE(ifq, m); \
if (m == NULL) \
break; \
m_freem(m); \
} \
IF_UNLOCK(ifq); \
} while (0)
#ifdef _KERNEL
#define IF_HANDOFF(ifq, m, ifp) if_handoff(ifq, m, ifp, 0)
#define IF_HANDOFF_ADJ(ifq, m, ifp, adj) if_handoff(ifq, m, ifp, adj)
static __inline int
if_handoff(struct ifqueue *ifq, struct mbuf *m, struct ifnet *ifp, int adjust)
{
int active = 0;
IF_LOCK(ifq);
if (_IF_QFULL(ifq)) {
_IF_DROP(ifq);
IF_UNLOCK(ifq);
m_freem(m);
return (0);
}
if (ifp != NULL) {
ifp->if_obytes += m->m_pkthdr.len + adjust;
if (m->m_flags & M_MCAST)
ifp->if_omcasts++;
active = ifp->if_flags & IFF_OACTIVE;
}
_IF_ENQUEUE(ifq, m);
IF_UNLOCK(ifq);
if (ifp != NULL && !active)
(*ifp->if_start)(ifp);
return (1);
}
/*
* 72 was chosen below because it is the size of a TCP/IP
* header (40) + the minimum mss (32).
*/
#define IF_MINMTU 72
#define IF_MAXMTU 65535
#endif /* _KERNEL */
/*
* The ifaddr structure contains information about one address
* of an interface. They are maintained by the different address families,
* are allocated and attached when an address is set, and are linked
* together so all addresses for an interface can be located.
*/
struct ifaddr {
struct sockaddr *ifa_addr; /* address of interface */
struct sockaddr *ifa_dstaddr; /* other end of p-to-p link */
#define ifa_broadaddr ifa_dstaddr /* broadcast address interface */
struct sockaddr *ifa_netmask; /* used to determine subnet */
struct if_data if_data; /* not all members are meaningful */
struct ifnet *ifa_ifp; /* back-pointer to interface */
TAILQ_ENTRY(ifaddr) ifa_link; /* queue macro glue */
void (*ifa_rtrequest) /* check or clean routes (+ or -)'d */
__P((int, struct rtentry *, struct rt_addrinfo *));
u_short ifa_flags; /* mostly rt_flags for cloning */
u_int ifa_refcnt; /* references to this structure */
int ifa_metric; /* cost of going out this interface */
#ifdef notdef
struct rtentry *ifa_rt; /* XXXX for ROUTETOIF ????? */
#endif
int (*ifa_claim_addr) /* check if an addr goes to this if */
__P((struct ifaddr *, struct sockaddr *));
};
#define IFA_ROUTE RTF_UP /* route installed */
/* for compatibility with other BSDs */
#define ifa_list ifa_link
/*
* The prefix structure contains information about one prefix
* of an interface. They are maintained by the different address families,
* are allocated and attached when an prefix or an address is set,
* and are linked together so all prefixes for an interface can be located.
*/
struct ifprefix {
struct sockaddr *ifpr_prefix; /* prefix of interface */
struct ifnet *ifpr_ifp; /* back-pointer to interface */
TAILQ_ENTRY(ifprefix) ifpr_list; /* queue macro glue */
u_char ifpr_plen; /* prefix length in bits */
u_char ifpr_type; /* protocol dependent prefix type */
};
/*
* Multicast address structure. This is analogous to the ifaddr
* structure except that it keeps track of multicast addresses.
* Also, the reference count here is a count of requests for this
* address, not a count of pointers to this structure.
*/
struct ifmultiaddr {
TAILQ_ENTRY(ifmultiaddr) ifma_link; /* queue macro glue */
struct sockaddr *ifma_addr; /* address this membership is for */
struct sockaddr *ifma_lladdr; /* link-layer translation, if any */
struct ifnet *ifma_ifp; /* back-pointer to interface */
u_int ifma_refcount; /* reference count */
void *ifma_protospec; /* protocol-specific state, if any */
};
#ifdef _KERNEL
#define IFAFREE(ifa) \
do { \
if ((ifa)->ifa_refcnt <= 0) \
ifafree(ifa); \
else \
(ifa)->ifa_refcnt--; \
} while (0)
struct ifindex_entry {
struct ifnet *ife_ifnet;
struct ifaddr *ife_ifnet_addr;
dev_t ife_dev;
};
#define ifnet_byindex(idx) ifindex_table[(idx)].ife_ifnet
#define ifaddr_byindex(idx) ifindex_table[(idx)].ife_ifnet_addr
#define ifdev_byindex(idx) ifindex_table[(idx)].ife_dev
extern struct ifnethead ifnet;
extern struct ifindex_entry *ifindex_table;
extern int ifqmaxlen;
extern struct ifnet *loif; /* first loopback interface */
extern int if_index;
void ether_ifattach __P((struct ifnet *, int));
void ether_ifdetach __P((struct ifnet *, int));
void ether_input __P((struct ifnet *, struct ether_header *, struct mbuf *));
void ether_demux __P((struct ifnet *, struct ether_header *, struct mbuf *));
int ether_output __P((struct ifnet *,
struct mbuf *, struct sockaddr *, struct rtentry *));
int ether_output_frame __P((struct ifnet *, struct mbuf *));
int ether_ioctl __P((struct ifnet *, int, caddr_t));
int if_addmulti __P((struct ifnet *, struct sockaddr *,
struct ifmultiaddr **));
int if_allmulti __P((struct ifnet *, int));
void if_attach __P((struct ifnet *));
int if_delmulti __P((struct ifnet *, struct sockaddr *));
void if_detach __P((struct ifnet *));
void if_down __P((struct ifnet *));
void if_route __P((struct ifnet *, int flag, int fam));
int if_setlladdr __P((struct ifnet *, const u_char *, int));
void if_unroute __P((struct ifnet *, int flag, int fam));
void if_up __P((struct ifnet *));
/*void ifinit __P((void));*/ /* declared in systm.h for main() */
int ifioctl __P((struct socket *, u_long, caddr_t, struct thread *));
int ifpromisc __P((struct ifnet *, int));
struct ifnet *ifunit __P((const char *));
struct ifnet *if_withname __P((struct sockaddr *));
int if_poll_recv_slow __P((struct ifnet *ifp, int *quotap));
void if_poll_xmit_slow __P((struct ifnet *ifp, int *quotap));
void if_poll_throttle __P((void));
void if_poll_unthrottle __P((void *));
void if_poll_init __P((void));
void if_poll __P((void));
struct ifaddr *ifa_ifwithaddr __P((struct sockaddr *));
struct ifaddr *ifa_ifwithdstaddr __P((struct sockaddr *));
struct ifaddr *ifa_ifwithnet __P((struct sockaddr *));
struct ifaddr *ifa_ifwithroute __P((int, struct sockaddr *,
struct sockaddr *));
struct ifaddr *ifaof_ifpforaddr __P((struct sockaddr *, struct ifnet *));
void ifafree __P((struct ifaddr *));
struct ifmultiaddr *ifmaof_ifpforaddr __P((struct sockaddr *,
struct ifnet *));
int if_simloop __P((struct ifnet *ifp, struct mbuf *m, int af, int hlen));
void if_clone_attach __P((struct if_clone *));
void if_clone_detach __P((struct if_clone *));
int if_clone_create __P((char *, int));
int if_clone_destroy __P((const char *));
#define IF_LLADDR(ifp) \
LLADDR((struct sockaddr_dl *) ifaddr_byindex((ifp)->if_index)->ifa_addr)
#ifdef DEVICE_POLLING
enum poll_cmd { POLL_ONLY, POLL_AND_CHECK_STATUS, POLL_DEREGISTER };
typedef void poll_handler_t __P((struct ifnet *ifp,
enum poll_cmd cmd, int count));
int ether_poll_register __P((poll_handler_t *h, struct ifnet *ifp));
int ether_poll_deregister __P((struct ifnet *ifp));
#endif /* DEVICE_POLLING */
#endif /* _KERNEL */
#endif /* !_NET_IF_VAR_H_ */