SUNRPC: Enforce atomic updates of rpc_cred->cr_flags

Convert to the use of atomic bitops...

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

5 files changed, 32 insertions, 30 deletions

diff --git a/include/linux/sunrpc/auth.h b/include/linux/sunrpc/auth.h
index d5bfc67461fc..8586503d5ebd 100644
--- a/include/linux/sunrpc/auth.h
+++ b/include/linux/sunrpc/auth.h
@@ -36,19 +36,19 @@ struct rpc_cred {
         struct hlist_node       cr_hash;        /* hash chain */
         struct rpc_auth *       cr_auth;
         const struct rpc_credops *cr_ops;
-        unsigned long           cr_expire;      /* when to gc */
-        atomic_t                cr_count;       /* ref count */
-        unsigned short          cr_flags;       /* various flags */
 #ifdef RPC_DEBUG
         unsigned long           cr_magic;       /* 0x0f4aa4f0 */
 #endif
+        unsigned long           cr_expire;      /* when to gc */
+        unsigned long           cr_flags;       /* various flags */
+        atomic_t                cr_count;       /* ref count */
 
         uid_t                   cr_uid;
 
         /* per-flavor data */
 };
-#define RPCAUTH_CRED_NEW        0x0001
-#define RPCAUTH_CRED_UPTODATE   0x0002
+#define RPCAUTH_CRED_NEW        0
+#define RPCAUTH_CRED_UPTODATE   1
 
 #define RPCAUTH_CRED_MAGIC      0x0f4aa4f0
 
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index 2156327da45b..4d7c78b05d1e 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -190,8 +190,8 @@ rpcauth_prune_expired(struct rpc_auth *auth, struct rpc_cred *cred, struct hlist
         if (atomic_read(&cred->cr_count) != 1)
                return;
         if (time_after(jiffies, cred->cr_expire + auth->au_credcache->expire))
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
-        if (!(cred->cr_flags & RPCAUTH_CRED_UPTODATE)) {
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
+        if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0) {
                 __hlist_del(&cred->cr_hash);
                 hlist_add_head(&cred->cr_hash, free);
         }
@@ -267,7 +267,7 @@ retry:
                 if (!IS_ERR(new))
                         goto retry;
                 cred = new;
-        } else if ((cred->cr_flags & RPCAUTH_CRED_NEW)
+        } else if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags)
                         && cred->cr_ops->cr_init != NULL
                         && !(flags & RPCAUTH_LOOKUP_NEW)) {
                 int res = cred->cr_ops->cr_init(auth, cred);
@@ -440,17 +440,19 @@ rpcauth_refreshcred(struct rpc_task *task)
 void
 rpcauth_invalcred(struct rpc_task *task)
 {
+        struct rpc_cred *cred = task->tk_msg.rpc_cred;
+
         dprintk("RPC: %5u invalidating %s cred %p\n",
-                task->tk_pid, task->tk_auth->au_ops->au_name, task->tk_msg.rpc_cred);
-        spin_lock(&rpc_credcache_lock);
-        if (task->tk_msg.rpc_cred)
-                task->tk_msg.rpc_cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
-        spin_unlock(&rpc_credcache_lock);
+                task->tk_pid, task->tk_auth->au_ops->au_name, cred);
+        if (cred)
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
 }
 
 int
 rpcauth_uptodatecred(struct rpc_task *task)
 {
-        return !(task->tk_msg.rpc_cred) ||
-                (task->tk_msg.rpc_cred->cr_flags & RPCAUTH_CRED_UPTODATE);
+        struct rpc_cred *cred = task->tk_msg.rpc_cred;
+
+        return cred == NULL ||
+                test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) != 0;
 }
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 766de0a41b22..55c47ae0a258 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -114,8 +114,8 @@ gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
         write_lock(&gss_ctx_lock);
         old = gss_cred->gc_ctx;
         gss_cred->gc_ctx = ctx;
-        cred->cr_flags |= RPCAUTH_CRED_UPTODATE;
-        cred->cr_flags &= ~RPCAUTH_CRED_NEW;
+        set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
+        clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
         write_unlock(&gss_ctx_lock);
         if (old)
                 gss_put_ctx(old);
@@ -128,7 +128,7 @@ gss_cred_is_uptodate_ctx(struct rpc_cred *cred)
         int res = 0;
 
         read_lock(&gss_ctx_lock);
-        if ((cred->cr_flags & RPCAUTH_CRED_UPTODATE) && gss_cred->gc_ctx)
+        if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) && gss_cred->gc_ctx)
                 res = 1;
         read_unlock(&gss_ctx_lock);
         return res;
@@ -732,7 +732,7 @@ gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
          * Note: in order to force a call to call_refresh(), we deliberately
          * fail to flag the credential as RPCAUTH_CRED_UPTODATE.
          */
-        cred->gc_base.cr_flags = RPCAUTH_CRED_NEW;
+        cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
         cred->gc_service = gss_auth->service;
         return &cred->gc_base;
 
@@ -764,7 +764,7 @@ gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
          * we don't really care if the credential has expired or not,
          * since the caller should be prepared to reinitialise it.
          */
-        if ((flags & RPCAUTH_LOOKUP_NEW) && (rc->cr_flags & RPCAUTH_CRED_NEW))
+        if ((flags & RPCAUTH_LOOKUP_NEW) && test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
                 goto out;
         /* Don't match with creds that have expired. */
         if (gss_cred->gc_ctx && time_after(jiffies, gss_cred->gc_ctx->gc_expiry))
@@ -820,7 +820,7 @@ gss_marshal(struct rpc_task *task, __be32 *p)
         mic.data = (u8 *)(p + 1);
         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
         if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         } else if (maj_stat != 0) {
                 printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat);
                 goto out_put_ctx;
@@ -873,7 +873,7 @@ gss_validate(struct rpc_task *task, __be32 *p)
 
         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         if (maj_stat)
                 goto out_bad;
         /* We leave it to unwrap to calculate au_rslack. For now we just
@@ -927,7 +927,7 @@ gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
         maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
         status = -EIO; /* XXX? */
         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         else if (maj_stat)
                 return status;
         q = xdr_encode_opaque(p, NULL, mic.len);
@@ -1026,7 +1026,7 @@ gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
         /* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
          * done anyway, so it's safe to put the request on the wire: */
         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         else if (maj_stat)
                 return status;
 
@@ -1113,7 +1113,7 @@ gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 
         maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         if (maj_stat != GSS_S_COMPLETE)
                 return status;
         return 0;
@@ -1138,7 +1138,7 @@ gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 
         maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
         if (maj_stat == GSS_S_CONTEXT_EXPIRED)
-                cred->cr_flags &= ~RPCAUTH_CRED_UPTODATE;
+                clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
         if (maj_stat != GSS_S_COMPLETE)
                 return status;
         if (ntohl(*(*p)++) != rqstp->rq_seqno)
diff --git a/net/sunrpc/auth_null.c b/net/sunrpc/auth_null.c
index fe9b6aaf91eb..6c905fb11c5d 100644
--- a/net/sunrpc/auth_null.c
+++ b/net/sunrpc/auth_null.c
@@ -76,7 +76,7 @@ nul_marshal(struct rpc_task *task, __be32 *p)
 static int
 nul_refresh(struct rpc_task *task)
 {
-        task->tk_msg.rpc_cred->cr_flags |= RPCAUTH_CRED_UPTODATE;
+        set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_msg.rpc_cred->cr_flags);
         return 0;
 }
 
@@ -136,7 +136,7 @@ struct rpc_cred null_cred = {
         .cr_auth        = &null_auth,
         .cr_ops         = &null_credops,
         .cr_count       = ATOMIC_INIT(1),
-        .cr_flags       = RPCAUTH_CRED_UPTODATE,
+        .cr_flags       = 1UL << RPCAUTH_CRED_UPTODATE,
 #ifdef RPC_DEBUG
         .cr_magic       = RPCAUTH_CRED_MAGIC,
 #endif
diff --git a/net/sunrpc/auth_unix.c b/net/sunrpc/auth_unix.c
index f17dabbab1c7..29d50ffa69d6 100644
--- a/net/sunrpc/auth_unix.c
+++ b/net/sunrpc/auth_unix.c
@@ -72,7 +72,7 @@ unx_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
                 return ERR_PTR(-ENOMEM);
 
         rpcauth_init_cred(&cred->uc_base, acred, auth, &unix_credops);
-        cred->uc_base.cr_flags = RPCAUTH_CRED_UPTODATE;
+        cred->uc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
         if (flags & RPCAUTH_LOOKUP_ROOTCREDS) {
                 cred->uc_uid = 0;
                 cred->uc_gid = 0;
@@ -172,7 +172,7 @@ unx_marshal(struct rpc_task *task, __be32 *p)
 static int
 unx_refresh(struct rpc_task *task)
 {
-        task->tk_msg.rpc_cred->cr_flags |= RPCAUTH_CRED_UPTODATE;
+        set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_msg.rpc_cred->cr_flags);
         return 0;
 }