From 3c6e0bc8a14cfc8e1d4ab87f46f77b070c815bf1 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 21 Apr 2016 20:51:54 -0400 Subject: sunrpc: plumb gfp_t parm into crcreate operation We need to be able to call the generic_cred creator from different contexts. Add a gfp_t parm to the crcreate operation and to rpcauth_lookup_credcache. For now, we just push the gfp_t parms up one level to the *_lookup_cred functions. Signed-off-by: Jeff Layton Signed-off-by: Anna Schumaker --- include/linux/sunrpc/auth.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/sunrpc/auth.h') diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 6a241a277249..3b616aa7e4d2 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -127,7 +127,7 @@ struct rpc_authops { void (*destroy)(struct rpc_auth *); struct rpc_cred * (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int); - struct rpc_cred * (*crcreate)(struct rpc_auth*, struct auth_cred *, int); + struct rpc_cred * (*crcreate)(struct rpc_auth*, struct auth_cred *, int, gfp_t); int (*list_pseudoflavors)(rpc_authflavor_t *, int); rpc_authflavor_t (*info2flavor)(struct rpcsec_gss_info *); int (*flavor2info)(rpc_authflavor_t, @@ -178,7 +178,7 @@ rpc_authflavor_t rpcauth_get_pseudoflavor(rpc_authflavor_t, int rpcauth_get_gssinfo(rpc_authflavor_t, struct rpcsec_gss_info *); int rpcauth_list_flavors(rpc_authflavor_t *, int); -struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int); +struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int, gfp_t); void rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *); struct rpc_cred * rpcauth_lookupcred(struct rpc_auth *, int); struct rpc_cred * rpcauth_generic_bind_cred(struct rpc_task *, struct rpc_cred *, int); -- cgit v1.2.3 From c065d229e308ede426a3608cf480c61983b36fb8 Mon Sep 17 00:00:00 2001 From: Weston Andros Adamson Date: Thu, 21 Apr 2016 20:51:55 -0400 Subject: sunrpc: add rpc_lookup_generic_cred Add function rpc_lookup_generic_cred, which allows lookups of a generic credential that's not current_cred(). [jlayton: add gfp_t parm] Signed-off-by: Jeff Layton Signed-off-by: Anna Schumaker --- include/linux/sunrpc/auth.h | 1 + net/sunrpc/auth_generic.c | 7 +++++++ 2 files changed, 8 insertions(+) (limited to 'include/linux/sunrpc/auth.h') diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 3b616aa7e4d2..16bd8f8fef8c 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -167,6 +167,7 @@ void rpc_destroy_authunix(void); struct rpc_cred * rpc_lookup_cred(void); struct rpc_cred * rpc_lookup_cred_nonblock(void); +struct rpc_cred * rpc_lookup_generic_cred(struct auth_cred *, int, gfp_t); struct rpc_cred * rpc_lookup_machine_cred(const char *service_name); int rpcauth_register(const struct rpc_authops *); int rpcauth_unregister(const struct rpc_authops *); diff --git a/net/sunrpc/auth_generic.c b/net/sunrpc/auth_generic.c index 6ed3e3df43e9..54dd3fdead54 100644 --- a/net/sunrpc/auth_generic.c +++ b/net/sunrpc/auth_generic.c @@ -38,6 +38,13 @@ struct rpc_cred *rpc_lookup_cred(void) } EXPORT_SYMBOL_GPL(rpc_lookup_cred); +struct rpc_cred * +rpc_lookup_generic_cred(struct auth_cred *acred, int flags, gfp_t gfp) +{ + return rpcauth_lookup_credcache(&generic_auth, acred, flags, gfp); +} +EXPORT_SYMBOL_GPL(rpc_lookup_generic_cred); + struct rpc_cred *rpc_lookup_cred_nonblock(void) { return rpcauth_lookupcred(&generic_auth, RPCAUTH_LOOKUP_RCU); -- cgit v1.2.3 From 62dbef2ae41393eba2f6853ca174130f2d09c7d3 Mon Sep 17 00:00:00 2001 From: Jeff Layton Date: Thu, 21 Apr 2016 20:51:56 -0400 Subject: sunrpc: add a get_rpccred_rcu inline Sometimes we might have a RCU managed credential pointer and don't want to use locking to handle it. Add a function that will take a reference to the cred iff the refcount is not already zero. Callers can dereference the pointer under the rcu_read_lock and use that function to take a reference only if the cred is not on its way to destruction. Signed-off-by: Jeff Layton Signed-off-by: Anna Schumaker --- include/linux/sunrpc/auth.h | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'include/linux/sunrpc/auth.h') diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 16bd8f8fef8c..6f36b2bf3e05 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -206,5 +206,23 @@ struct rpc_cred * get_rpccred(struct rpc_cred *cred) return cred; } +/** + * get_rpccred_rcu - get a reference to a cred using rcu-protected pointer + * @cred: cred of which to take a reference + * + * In some cases, we may have a pointer to a credential to which we + * want to take a reference, but don't already have one. Because these + * objects are freed using RCU, we can access the cr_count while its + * on its way to destruction and only take a reference if it's not already + * zero. + */ +static inline struct rpc_cred * +get_rpccred_rcu(struct rpc_cred *cred) +{ + if (atomic_inc_not_zero(&cred->cr_count)) + return cred; + return NULL; +} + #endif /* __KERNEL__ */ #endif /* _LINUX_SUNRPC_AUTH_H */ -- cgit v1.2.3 From 9a8f6b5ea275ff01fc8ef3b8630a3d4ed6b0a362 Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 16 May 2016 17:42:42 -0400 Subject: SUNRPC: Ensure get_rpccred() and put_rpccred() can take NULL arguments Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker --- include/linux/sunrpc/auth.h | 3 ++- net/sunrpc/auth.c | 5 +++-- 2 files changed, 5 insertions(+), 3 deletions(-) (limited to 'include/linux/sunrpc/auth.h') diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h index 6f36b2bf3e05..899791573a40 100644 --- a/include/linux/sunrpc/auth.h +++ b/include/linux/sunrpc/auth.h @@ -202,7 +202,8 @@ char * rpcauth_stringify_acceptor(struct rpc_cred *); static inline struct rpc_cred * get_rpccred(struct rpc_cred *cred) { - atomic_inc(&cred->cr_count); + if (cred != NULL) + atomic_inc(&cred->cr_count); return cred; } diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c index e0bb30fd2ed3..040ff627c18a 100644 --- a/net/sunrpc/auth.c +++ b/net/sunrpc/auth.c @@ -703,8 +703,7 @@ rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags) new = rpcauth_bind_new_cred(task, lookupflags); if (IS_ERR(new)) return PTR_ERR(new); - if (req->rq_cred != NULL) - put_rpccred(req->rq_cred); + put_rpccred(req->rq_cred); req->rq_cred = new; return 0; } @@ -712,6 +711,8 @@ rpcauth_bindcred(struct rpc_task *task, struct rpc_cred *cred, int flags) void put_rpccred(struct rpc_cred *cred) { + if (cred == NULL) + return; /* Fast path for unhashed credentials */ if (test_bit(RPCAUTH_CRED_HASHED, &cred->cr_flags) == 0) { if (atomic_dec_and_test(&cred->cr_count)) -- cgit v1.2.3