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>
diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 2278a50..2e6a148 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -181,6 +181,11 @@
(*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 @@
.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,
diff --git a/net/sunrpc/cache.c b/net/sunrpc/cache.c
index c8e7d2d..e438352 100644
--- a/net/sunrpc/cache.c
+++ b/net/sunrpc/cache.c
@@ -176,7 +176,13 @@
}
EXPORT_SYMBOL_GPL(sunrpc_cache_update);
-static int cache_make_upcall(struct cache_detail *detail, struct cache_head *h);
+static int cache_make_upcall(struct cache_detail *cd, struct cache_head *h)
+{
+ if (!cd->cache_upcall)
+ return -EINVAL;
+ return cd->cache_upcall(cd, h);
+}
+
/*
* This is the generic cache management routine for all
* the authentication caches.
@@ -322,7 +328,7 @@
if (p == NULL)
goto out_nomem;
- if (cd->cache_request || cd->cache_parse) {
+ if (cd->cache_upcall || cd->cache_parse) {
p = proc_create_data("channel", S_IFREG|S_IRUSR|S_IWUSR,
cd->proc_ent, &cache_file_operations, cd);
cd->channel_ent = p;
@@ -1080,10 +1086,16 @@
}
/*
- * register an upcall request to user-space.
+ * register an upcall request to user-space and queue it up for read() by the
+ * upcall daemon.
+ *
* Each request is at most one page long.
*/
-static int cache_make_upcall(struct cache_detail *detail, struct cache_head *h)
+int sunrpc_cache_pipe_upcall(struct cache_detail *detail, struct cache_head *h,
+ void (*cache_request)(struct cache_detail *,
+ struct cache_head *,
+ char **,
+ int *))
{
char *buf;
@@ -1091,9 +1103,6 @@
char *bp;
int len;
- if (detail->cache_request == NULL)
- return -EINVAL;
-
if (atomic_read(&detail->readers) == 0 &&
detail->last_close < get_seconds() - 30) {
warn_no_listener(detail);
@@ -1112,7 +1121,7 @@
bp = buf; len = PAGE_SIZE;
- detail->cache_request(detail, h, &bp, &len);
+ cache_request(detail, h, &bp, &len);
if (len < 0) {
kfree(buf);
@@ -1130,6 +1139,7 @@
wake_up(&queue_wait);
return 0;
}
+EXPORT_SYMBOL_GPL(sunrpc_cache_pipe_upcall);
/*
* parse a message from user-space and pass it
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 5c865e2..6caffa3 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -171,6 +171,11 @@
(*bpp)[-1] = '\n';
}
+static int ip_map_upcall(struct cache_detail *cd, struct cache_head *h)
+{
+ return sunrpc_cache_pipe_upcall(cd, h, ip_map_request);
+}
+
static struct ip_map *ip_map_lookup(char *class, struct in6_addr *addr);
static int ip_map_update(struct ip_map *ipm, struct unix_domain *udom, time_t expiry);
@@ -289,7 +294,7 @@
.hash_table = ip_table,
.name = "auth.unix.ip",
.cache_put = ip_map_put,
- .cache_request = ip_map_request,
+ .cache_upcall = ip_map_upcall,
.cache_parse = ip_map_parse,
.cache_show = ip_map_show,
.match = ip_map_match,
@@ -523,6 +528,11 @@
(*bpp)[-1] = '\n';
}
+static int unix_gid_upcall(struct cache_detail *cd, struct cache_head *h)
+{
+ return sunrpc_cache_pipe_upcall(cd, h, unix_gid_request);
+}
+
static struct unix_gid *unix_gid_lookup(uid_t uid);
extern struct cache_detail unix_gid_cache;
@@ -622,7 +632,7 @@
.hash_table = gid_table,
.name = "auth.unix.gid",
.cache_put = unix_gid_put,
- .cache_request = unix_gid_request,
+ .cache_upcall = unix_gid_upcall,
.cache_parse = unix_gid_parse,
.cache_show = unix_gid_show,
.match = unix_gid_match,