[PATCH v2 2/5] SUNRPC: create unix gid cache per network namespace

Stanislav Kinsbursky
2012-01-19T17:42:50Z

v2:
1) fixed silly usage of template cache as a real one (this code left from
static global cache for all)

This patch makes unix_gid_cache cache detail allocated and registered per
network namespace context.
Thus with this patch unix_gid_cache contents for network namespace "X" are
controlled from proc file system mount for the same network namespace "X".

Signed-off-by: Stanislav Kinsbursky <skinsbursky@parallels.com>

---
net/sunrpc/netns.h | 1 +
net/sunrpc/sunrpc_syms.c | 14 ++++++++---
net/sunrpc/svcauth_unix.c | 55 ++++++++++++++++++++++++++++++++++-----------
3 files changed, 52 insertions(+), 18 deletions(-)

diff --git a/net/sunrpc/netns.h b/net/sunrpc/netns.h
index 1fdeb1b..309f88d 100644
--- a/net/sunrpc/netns.h
+++ b/net/sunrpc/netns.h
@@ -9,6 +9,7 @@ struct cache_detail;
struct sunrpc_net {
struct proc_dir_entry *proc_net_rpc;
struct cache_detail *ip_map_cache;
+ struct cache_detail *unix_gid_cache;

struct super_block *pipefs_sb;
struct mutex pipefs_sb_lock;
diff --git a/net/sunrpc/sunrpc_syms.c b/net/sunrpc/sunrpc_syms.c
index b4217dc..38a72a1 100644
--- a/net/sunrpc/sunrpc_syms.c
+++ b/net/sunrpc/sunrpc_syms.c
@@ -26,6 +26,9 @@

int sunrpc_net_id;

+extern int unix_gid_cache_create(struct net *net);
+extern int unix_gid_cache_destroy(struct net *net);
+
static __net_init int sunrpc_init_net(struct net *net)
{
int err;
@@ -39,11 +42,17 @@ static __net_init int sunrpc_init_net(struct net *net)
if (err)
goto err_ipmap;

+ err = unix_gid_cache_create(net);
+ if (err)
+ goto err_unixgid;
+
rpc_pipefs_init_net(net);
INIT_LIST_HEAD(&sn->all_clients);
spin_lock_init(&sn->rpc_client_lock);
return 0;

+err_unixgid:
+ ip_map_cache_destroy(net);
err_ipmap:
rpc_proc_exit(net);
err_proc:
@@ -52,6 +61,7 @@ err_proc:

static __net_exit void sunrpc_exit_net(struct net *net)
{
+ unix_gid_cache_destroy(net);
ip_map_cache_destroy(net);
rpc_proc_exit(net);
}
@@ -63,8 +73,6 @@ static struct pernet_operations sunrpc_net_ops = {
.size = sizeof(struct sunrpc_net),
};

-extern struct cache_detail unix_gid_cache;
-
static int __init
init_sunrpc(void)
{
@@ -86,7 +94,6 @@ init_sunrpc(void)
#ifdef RPC_DEBUG
rpc_register_sysctl();
#endif
- cache_register(&unix_gid_cache);
svc_init_xprt_sock(); /* svc sock transport */
init_socket_xprt(); /* clnt sock transport */
return 0;
@@ -109,7 +116,6 @@ cleanup_sunrpc(void)
svc_cleanup_xprt_sock();
unregister_rpc_pipefs();
rpc_destroy_mempool();
- cache_unregister(&unix_gid_cache);
unregister_pernet_subsys(&sunrpc_net_ops);
#ifdef RPC_DEBUG
rpc_unregister_sysctl();
diff --git a/net/sunrpc/svcauth_unix.c b/net/sunrpc/svcauth_unix.c
index 2f8c426..a6eef38 100644
--- a/net/sunrpc/svcauth_unix.c
+++ b/net/sunrpc/svcauth_unix.c
@@ -436,7 +436,6 @@ struct unix_gid {
uid_t uid;
struct group_info *gi;
};
-static struct cache_head *gid_table[GID_HASHMAX];

static void unix_gid_put(struct kref *kref)
{
@@ -494,8 +493,7 @@ 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;
+static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, uid_t uid);

static int unix_gid_parse(struct cache_detail *cd,
char *mesg, int mlen)
@@ -539,19 +537,19 @@ static int unix_gid_parse(struct cache_detail *cd,
GROUP_AT(ug.gi, i) = gid;
}

- ugp = unix_gid_lookup(uid);
+ ugp = unix_gid_lookup(cd, uid);
if (ugp) {
struct cache_head *ch;
ug.h.flags = 0;
ug.h.expiry_time = expiry;
- ch = sunrpc_cache_update(&unix_gid_cache,
+ ch = sunrpc_cache_update(cd,
&ug.h, &ugp->h,
hash_long(uid, GID_HASHBITS));
if (!ch)
err = -ENOMEM;
else {
err = 0;
- cache_put(ch, &unix_gid_cache);
+ cache_put(ch, cd);
}
} else
err = -ENOMEM;
@@ -587,10 +585,9 @@ static int unix_gid_show(struct seq_file *m,
return 0;
}

-struct cache_detail unix_gid_cache = {
+static struct cache_detail unix_gid_cache_template = {
.owner = THIS_MODULE,
.hash_size = GID_HASHMAX,
- .hash_table = gid_table,
.name = "auth.unix.gid",
.cache_put = unix_gid_put,
.cache_upcall = unix_gid_upcall,
@@ -602,14 +599,42 @@ struct cache_detail unix_gid_cache = {
.alloc = unix_gid_alloc,
};

-static struct unix_gid *unix_gid_lookup(uid_t uid)
+int unix_gid_cache_create(struct net *net)
+{
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+ struct cache_detail *cd;
+ int err;
+
+ cd = cache_create_net(&unix_gid_cache_template, net);
+ if (IS_ERR(cd))
+ return PTR_ERR(cd);
+ err = cache_register_net(cd, net);
+ if (err) {
+ cache_destroy_net(cd, net);
+ return err;
+ }
+ sn->unix_gid_cache = cd;
+ return 0;
+}
+
+void unix_gid_cache_destroy(struct net *net)
+{
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+ struct cache_detail *cd = sn->unix_gid_cache;
+
+ sn->unix_gid_cache = NULL;
+ cache_purge(cd);
+ cache_unregister_net(cd, net);
+ cache_destroy_net(cd, net);
+}
+
+static struct unix_gid *unix_gid_lookup(struct cache_detail *cd, uid_t uid)
{
struct unix_gid ug;
struct cache_head *ch;

ug.uid = uid;
- ch = sunrpc_cache_lookup(&unix_gid_cache, &ug.h,
- hash_long(uid, GID_HASHBITS));
+ ch = sunrpc_cache_lookup(cd, &ug.h, hash_long(uid, GID_HASHBITS));
if (ch)
return container_of(ch, struct unix_gid, h);
else
@@ -621,11 +646,13 @@ static struct group_info *unix_gid_find(uid_t uid, struct svc_rqst *rqstp)
struct unix_gid *ug;
struct group_info *gi;
int ret;
+ struct sunrpc_net *sn = net_generic(rqstp->rq_xprt->xpt_net,
+ sunrpc_net_id);

- ug = unix_gid_lookup(uid);
+ ug = unix_gid_lookup(sn->unix_gid_cache, uid);
if (!ug)
return ERR_PTR(-EAGAIN);
- ret = cache_check(&unix_gid_cache, &ug->h, &rqstp->rq_chandle);
+ ret = cache_check(sn->unix_gid_cache, &ug->h, &rqstp->rq_chandle);
switch (ret) {
case -ENOENT:
return ERR_PTR(-ENOENT);
@@ -633,7 +660,7 @@ static struct group_info *unix_gid_find(uid_t uid, struct svc_rqst *rqstp)
return ERR_PTR(-ESHUTDOWN);
case 0:
gi = get_group_info(ug->gi);
- cache_put(&ug->h, &unix_gid_cache);
+ cache_put(&ug->h, sn->unix_gid_cache);
return gi;
default:
return ERR_PTR(-EAGAIN);