NetBSD/sys/netnatm
dyoung 72f0a6dfb0 Eliminate address family-specific route caches (struct route, struct
route_in6, struct route_iso), replacing all caches with a struct
route.

The principle benefit of this change is that all of the protocol
families can benefit from route cache-invalidation, which is
necessary for correct routing.  Route-cache invalidation fixes an
ancient PR, kern/3508, at long last; it fixes various other PRs,
also.

Discussions with and ideas from Joerg Sonnenberger influenced this
work tremendously.  Of course, all design oversights and bugs are
mine.

DETAILS

1 I added to each address family a pool of sockaddrs.  I have
  introduced routines for allocating, copying, and duplicating,
  and freeing sockaddrs:

        struct sockaddr *sockaddr_alloc(sa_family_t af, int flags);
        struct sockaddr *sockaddr_copy(struct sockaddr *dst,
                                       const struct sockaddr *src);
        struct sockaddr *sockaddr_dup(const struct sockaddr *src, int flags);
        void sockaddr_free(struct sockaddr *sa);

  sockaddr_alloc() returns either a sockaddr from the pool belonging
  to the specified family, or NULL if the pool is exhausted.  The
  returned sockaddr has the right size for that family; sa_family
  and sa_len fields are initialized to the family and sockaddr
  length---e.g., sa_family = AF_INET and sa_len = sizeof(struct
  sockaddr_in).  sockaddr_free() puts the given sockaddr back into
  its family's pool.

  sockaddr_dup() and sockaddr_copy() work analogously to strdup()
  and strcpy(), respectively.  sockaddr_copy() KASSERTs that the
  family of the destination and source sockaddrs are alike.

  The 'flags' argumet for sockaddr_alloc() and sockaddr_dup() is
  passed directly to pool_get(9).

2 I added routines for initializing sockaddrs in each address
  family, sockaddr_in_init(), sockaddr_in6_init(), sockaddr_iso_init(),
  etc.  They are fairly self-explanatory.

3 structs route_in6 and route_iso are no more.  All protocol families
  use struct route.  I have changed the route cache, 'struct route',
  so that it does not contain storage space for a sockaddr.  Instead,
  struct route points to a sockaddr coming from the pool the sockaddr
  belongs to.  I added a new method to struct route, rtcache_setdst(),
  for setting the cache destination:

        int rtcache_setdst(struct route *, const struct sockaddr *);

  rtcache_setdst() returns 0 on success, or ENOMEM if no memory is
  available to create the sockaddr storage.

  It is now possible for rtcache_getdst() to return NULL if, say,
  rtcache_setdst() failed.  I check the return value for NULL
  everywhere in the kernel.

4 Each routing domain (struct domain) has a list of live route
  caches, dom_rtcache.  rtflushall(sa_family_t af) looks up the
  domain indicated by 'af', walks the domain's list of route caches
  and invalidates each one.
2007-05-02 20:40:22 +00:00
..
Makefile
files.netnatm
natm.c Kill caddr_t; there will be some MI fallout, but it will be fixed shortly. 2007-03-04 05:59:00 +00:00
natm.h merge ktrace-lwp. 2005-12-11 12:16:03 +00:00
natm_pcb.c merge ktrace-lwp. 2005-12-11 12:16:03 +00:00
natm_proto.c Eliminate address family-specific route caches (struct route, struct 2007-05-02 20:40:22 +00:00