SUNRPC: Allow the cache_detail to specify alternative upcall mechanisms

For events that are rare, such as referral DNS lookups, it makes limited
sense to have a daemon constantly listening for upcalls on a channel. An
alternative in those cases might simply be to run the app that fills the
cache using call_usermodehelper_exec() and friends.

The following patch allows the cache_detail to specify alternative upcall
mechanisms for these particular cases.

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 2278a50c6444..2e6a148d277c 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -181,6 +181,11 @@ static void rsi_request(struct cache_detail *cd,
         (*bpp)[-1] = '\n';
 }
 
+static int rsi_upcall(struct cache_detail *cd, struct cache_head *h)
+{
+        return sunrpc_cache_pipe_upcall(cd, h, rsi_request);
+}
+
 
 static int rsi_parse(struct cache_detail *cd,
                     char *mesg, int mlen)
@@ -270,7 +275,7 @@ static struct cache_detail rsi_cache = {
         .hash_table     = rsi_table,
         .name           = "auth.rpcsec.init",
         .cache_put      = rsi_put,
-        .cache_request  = rsi_request,
+        .cache_upcall   = rsi_upcall,
         .cache_parse    = rsi_parse,
         .match          = rsi_match,
         .init           = rsi_init,