[IPSEC] xfrm: Undo afinfo lock proliferation

The number of locks used to manage afinfo structures can easily be reduced
down to one each for policy and state respectively.  This is based on the
observation that the write locks are only held by module insertion/removal
which are very rare events so there is no need to further differentiate
between the insertion of modules like ipv6 versus esp6.

The removal of the read locks in xfrm4_policy.c/xfrm6_policy.c might look
suspicious at first.  However, after you realise that nobody ever takes
the corresponding write lock you'll feel better :)

As far as I can gather it's an attempt to guard against the removal of
the corresponding modules.  Since neither module can be unloaded at all
we can leave it to whoever fixes up IPv6 unloading :)

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 1 insertions, 8 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index afa508d92c9..ed7c9747059 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -204,8 +204,7 @@ struct xfrm_type;
 struct xfrm_dst;
 struct xfrm_policy_afinfo {
         unsigned short          family;
-        rwlock_t                lock;
-        struct xfrm_type_map    *type_map;
+        struct xfrm_type        *type_map[256];
         struct dst_ops          *dst_ops;
         void                    (*garbage_collect)(void);
         int                     (*dst_lookup)(struct xfrm_dst **dst, struct flowi *fl);
@@ -232,7 +231,6 @@ extern int __xfrm_state_delete(struct xfrm_state *x);
 
 struct xfrm_state_afinfo {
         unsigned short          family;
-        rwlock_t                lock;
         struct list_head        *state_bydst;
         struct list_head        *state_byspi;
         int                     (*init_flags)(struct xfrm_state *x);
@@ -264,11 +262,6 @@ struct xfrm_type
         u32                     (*get_max_size)(struct xfrm_state *, int size);
 };
 
-struct xfrm_type_map {
-        rwlock_t                lock;
-        struct xfrm_type        *map[256];
-};
-
 extern int xfrm_register_type(struct xfrm_type *type, unsigned short family);
 extern int xfrm_unregister_type(struct xfrm_type *type, unsigned short family);
 extern struct xfrm_type *xfrm_get_type(u8 proto, unsigned short family);