freebsd-nq/sys/net/if_llatbl.h
Alexander V. Chernikov 5a2555160f * Split allocation and table linking for lle's.
Before that, the logic besides lle_create() was the following:
  return existing if found, create if not. This behaviour was error-prone
  since we had to deal with 'sudden' static<>dynamic lle changes.
  This commit fixes bunch of different issues like:
  - refcount leak when lle is converted to static.
    Simple check case:
    console 1:
    while true;
      do for i in `arp -an|awk '$4~/incomp/{print$2}'|tr -d '()'`;
        do arp -s $i 00:22:44:66:88:00 ; arp -d $i;
      done;
    done
   console 2:
    ping -f any-dead-host-in-L2
   console 3:
    # watch for memory consumption:
    vmstat -m | awk '$1~/lltable/{print$2}'
  - possible problems in arptimer() / nd6_timer() when dropping/reacquiring
   lock.
  New logic explicitly handles use-or-create cases in every lla_create
  user. Basically, most of the changes are purely mechanical. However,
  we explicitly avoid using existing lle's for interface/static LLE records.
* While here, call lle_event handlers on all real table lle change.
* Create lltable_free_entry() calling existing per-lltable
  lle_free_t callback for entry deletion
2015-08-20 12:05:17 +00:00

253 lines
8.2 KiB
C

/*
* Copyright (c) 2004 Luigi Rizzo, Alessandro Cerri. All rights reserved.
* Copyright (c) 2004-2008 Qing Li. All rights reserved.
* Copyright (c) 2008 Kip Macy. 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.
*
* THIS SOFTWARE IS PROVIDED BY 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 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("$FreeBSD$");
#ifndef _NET_IF_LLATBL_H_
#define _NET_IF_LLATBL_H_
#include <sys/_rwlock.h>
#include <netinet/in.h>
struct ifnet;
struct sysctl_req;
struct rt_msghdr;
struct rt_addrinfo;
struct llentry;
LIST_HEAD(llentries, llentry);
extern struct rwlock lltable_rwlock;
#define LLTABLE_RLOCK() rw_rlock(&lltable_rwlock)
#define LLTABLE_RUNLOCK() rw_runlock(&lltable_rwlock)
#define LLTABLE_WLOCK() rw_wlock(&lltable_rwlock)
#define LLTABLE_WUNLOCK() rw_wunlock(&lltable_rwlock)
#define LLTABLE_LOCK_ASSERT() rw_assert(&lltable_rwlock, RA_LOCKED)
/*
* Code referencing llentry must at least hold
* a shared lock
*/
struct llentry {
LIST_ENTRY(llentry) lle_next;
union {
struct in_addr addr4;
struct in6_addr addr6;
} r_l3addr;
union {
uint64_t mac_aligned;
uint16_t mac16[3];
uint8_t mac8[20]; /* IB needs 20 bytes. */
} ll_addr;
uint32_t spare0;
uint64_t spare1;
struct lltable *lle_tbl;
struct llentries *lle_head;
void (*lle_free)(struct llentry *);
struct mbuf *la_hold;
int la_numheld; /* # of packets currently held */
time_t la_expire;
uint16_t la_flags;
uint16_t la_asked;
uint16_t la_preempt;
uint16_t ln_byhint;
int16_t ln_state; /* IPv6 has ND6_LLINFO_NOSTATE == -2 */
uint16_t ln_router;
time_t ln_ntick;
int lle_refcnt;
LIST_ENTRY(llentry) lle_chain; /* chain of deleted items */
struct callout lle_timer;
struct rwlock lle_lock;
};
#define LLE_WLOCK(lle) rw_wlock(&(lle)->lle_lock)
#define LLE_RLOCK(lle) rw_rlock(&(lle)->lle_lock)
#define LLE_WUNLOCK(lle) rw_wunlock(&(lle)->lle_lock)
#define LLE_RUNLOCK(lle) rw_runlock(&(lle)->lle_lock)
#define LLE_DOWNGRADE(lle) rw_downgrade(&(lle)->lle_lock)
#define LLE_TRY_UPGRADE(lle) rw_try_upgrade(&(lle)->lle_lock)
#define LLE_LOCK_INIT(lle) rw_init_flags(&(lle)->lle_lock, "lle", RW_DUPOK)
#define LLE_LOCK_DESTROY(lle) rw_destroy(&(lle)->lle_lock)
#define LLE_WLOCK_ASSERT(lle) rw_assert(&(lle)->lle_lock, RA_WLOCKED)
#define LLE_IS_VALID(lle) (((lle) != NULL) && ((lle) != (void *)-1))
#define LLE_ADDREF(lle) do { \
LLE_WLOCK_ASSERT(lle); \
KASSERT((lle)->lle_refcnt >= 0, \
("negative refcnt %d on lle %p", \
(lle)->lle_refcnt, (lle))); \
(lle)->lle_refcnt++; \
} while (0)
#define LLE_REMREF(lle) do { \
LLE_WLOCK_ASSERT(lle); \
KASSERT((lle)->lle_refcnt > 0, \
("bogus refcnt %d on lle %p", \
(lle)->lle_refcnt, (lle))); \
(lle)->lle_refcnt--; \
} while (0)
#define LLE_FREE_LOCKED(lle) do { \
if ((lle)->lle_refcnt == 1) \
(lle)->lle_free(lle); \
else { \
LLE_REMREF(lle); \
LLE_WUNLOCK(lle); \
} \
/* guard against invalid refs */ \
(lle) = NULL; \
} while (0)
#define LLE_FREE(lle) do { \
LLE_WLOCK(lle); \
LLE_FREE_LOCKED(lle); \
} while (0)
typedef struct llentry *(llt_lookup_t)(struct lltable *, u_int flags,
const struct sockaddr *l3addr);
typedef struct llentry *(llt_alloc_t)(struct lltable *, u_int flags,
const struct sockaddr *l3addr);
typedef int (llt_delete_t)(struct lltable *, u_int flags,
const struct sockaddr *l3addr);
typedef void (llt_prefix_free_t)(struct lltable *,
const struct sockaddr *prefix, const struct sockaddr *mask, u_int flags);
typedef int (llt_dump_entry_t)(struct lltable *, struct llentry *,
struct sysctl_req *);
typedef uint32_t (llt_hash_t)(const struct llentry *, uint32_t);
typedef int (llt_match_prefix_t)(const struct sockaddr *,
const struct sockaddr *, u_int, struct llentry *);
typedef void (llt_free_entry_t)(struct lltable *, struct llentry *);
typedef void (llt_fill_sa_entry_t)(const struct llentry *, struct sockaddr *);
typedef void (llt_free_tbl_t)(struct lltable *);
typedef void (llt_link_entry_t)(struct lltable *, struct llentry *);
typedef void (llt_unlink_entry_t)(struct llentry *);
typedef int (llt_foreach_cb_t)(struct lltable *, struct llentry *, void *);
typedef int (llt_foreach_entry_t)(struct lltable *, llt_foreach_cb_t *, void *);
struct lltable {
SLIST_ENTRY(lltable) llt_link;
int llt_af;
int llt_hsize;
struct llentries *lle_head;
struct ifnet *llt_ifp;
llt_lookup_t *llt_lookup;
llt_alloc_t *llt_alloc_entry;
llt_delete_t *llt_delete;
llt_prefix_free_t *llt_prefix_free;
llt_dump_entry_t *llt_dump_entry;
llt_hash_t *llt_hash;
llt_match_prefix_t *llt_match_prefix;
llt_free_entry_t *llt_free_entry;
llt_foreach_entry_t *llt_foreach_entry;
llt_link_entry_t *llt_link_entry;
llt_unlink_entry_t *llt_unlink_entry;
llt_fill_sa_entry_t *llt_fill_sa_entry;
llt_free_tbl_t *llt_free_tbl;
};
MALLOC_DECLARE(M_LLTABLE);
/*
* LLentry flags
*/
#define LLE_DELETED 0x0001 /* entry must be deleted */
#define LLE_STATIC 0x0002 /* entry is static */
#define LLE_IFADDR 0x0004 /* entry is interface addr */
#define LLE_VALID 0x0008 /* ll_addr is valid */
#define LLE_PUB 0x0020 /* publish entry ??? */
#define LLE_LINKED 0x0040 /* linked to lookup structure */
/* LLE request flags */
#define LLE_EXCLUSIVE 0x2000 /* return lle xlocked */
#define LLATBL_HASH(key, mask) \
(((((((key >> 8) ^ key) >> 8) ^ key) >> 8) ^ key) & mask)
struct lltable *lltable_allocate_htbl(uint32_t hsize);
void lltable_free(struct lltable *);
void lltable_link(struct lltable *llt);
void lltable_prefix_free(int, struct sockaddr *,
struct sockaddr *, u_int);
#if 0
void lltable_drain(int);
#endif
int lltable_sysctl_dumparp(int, struct sysctl_req *);
size_t llentry_free(struct llentry *);
struct llentry *llentry_alloc(struct ifnet *, struct lltable *,
struct sockaddr_storage *);
/* helper functions */
size_t lltable_drop_entry_queue(struct llentry *);
struct llentry *lltable_alloc_entry(struct lltable *llt, u_int flags,
const struct sockaddr *l4addr);
void lltable_free_entry(struct lltable *llt, struct llentry *lle);
void lltable_link_entry(struct lltable *llt, struct llentry *lle);
void lltable_unlink_entry(struct lltable *llt, struct llentry *lle);
void lltable_fill_sa_entry(const struct llentry *lle, struct sockaddr *sa);
struct ifnet *lltable_get_ifp(const struct lltable *llt);
int lltable_get_af(const struct lltable *llt);
int lltable_foreach_lle(struct lltable *llt, llt_foreach_cb_t *f,
void *farg);
/*
* Generic link layer address lookup function.
*/
static __inline struct llentry *
lla_lookup(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
{
return (llt->llt_lookup(llt, flags, l3addr));
}
static __inline int
lla_delete(struct lltable *llt, u_int flags, const struct sockaddr *l3addr)
{
return (llt->llt_delete(llt, flags, l3addr));
}
int lla_rt_output(struct rt_msghdr *, struct rt_addrinfo *);
#include <sys/eventhandler.h>
enum {
LLENTRY_RESOLVED,
LLENTRY_TIMEDOUT,
LLENTRY_DELETED,
LLENTRY_EXPIRED,
};
typedef void (*lle_event_fn)(void *, struct llentry *, int);
EVENTHANDLER_DECLARE(lle_event, lle_event_fn);
#endif /* _NET_IF_LLATBL_H_ */