SUNRPC: Fix up svc_unregister()

With the new rpcbind code, a PMAP_UNSET will not have any effect on
services registered via rpcbind v3 or v4.

Implement a version of svc_unregister() that uses an RPCB_UNSET with
an empty netid string to make sure we have cleared *all* entries for
a kernel RPC service when shutting down, or before starting a fresh
instance of the service.

Use the new version only when CONFIG_SUNRPC_REGISTER_V4 is enabled;
otherwise, the legacy PMAP version is used to ensure complete
backwards-compatibility with the Linux portmapper daemon.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
This commit is contained in:
Chuck Lever 2008-09-25 11:56:57 -04:00 committed by J. Bruce Fields
parent 9d548b9c95
commit f6fb3f6f59

View File

@ -896,31 +896,51 @@ int svc_register(const struct svc_serv *serv, const unsigned short proto,
return error;
}
#ifdef CONFIG_SUNRPC_REGISTER_V4
static void __svc_unregister(const u32 program, const u32 version,
const char *progname)
{
struct sockaddr_in6 sin6 = {
.sin6_family = AF_INET6,
.sin6_addr = IN6ADDR_ANY_INIT,
.sin6_port = 0,
};
int error;
error = rpcb_v4_register(program, version,
(struct sockaddr *)&sin6, "");
dprintk("svc: %s(%sv%u), error %d\n",
__func__, progname, version, error);
}
#else /* CONFIG_SUNRPC_REGISTER_V4 */
static void __svc_unregister(const u32 program, const u32 version,
const char *progname)
{
int error;
error = rpcb_register(program, version, 0, 0);
dprintk("svc: %s(%sv%u), error %d\n",
__func__, progname, version, error);
}
#endif /* CONFIG_SUNRPC_REGISTER_V4 */
/*
* All transport protocols and ports for this service are removed
* from the local rpcbind database if the service is not hidden.
* All netids, bind addresses and ports registered for [program, version]
* are removed from the local rpcbind database (if the service is not
* hidden) to make way for a new instance of the service.
*
* The result of unregistration is reported via dprintk for those
* who want verification of the result, but is otherwise not
* important.
*
* The local rpcbind daemon listens on either only IPv6 or only
* IPv4. The kernel can't tell how it's configured. However,
* AF_INET addresses are mapped to AF_INET6 in IPv6-only config-
* urations, so even an unregistration request on AF_INET will
* get to a local rpcbind daemon listening only on AF_INET6. So
* we always unregister via AF_INET.
*
* At this point we don't need rpcbind version 4 for unregis-
* tration: A v2 UNSET request will clear all transports (netids),
* addresses, and address families for [program, version].
* The result of unregistration is reported via dprintk for those who want
* verification of the result, but is otherwise not important.
*/
static void svc_unregister(const struct svc_serv *serv)
{
struct svc_program *progp;
unsigned long flags;
unsigned int i;
int error;
clear_thread_flag(TIF_SIGPENDING);
@ -931,9 +951,7 @@ static void svc_unregister(const struct svc_serv *serv)
if (progp->pg_vers[i]->vs_hidden)
continue;
error = rpcb_register(progp->pg_prog, i, 0, 0);
dprintk("svc: svc_unregister(%sv%u), error %d\n",
progp->pg_name, i, error);
__svc_unregister(progp->pg_prog, i, progp->pg_name);
}
}