[PATCH] sunrpc: move bkl locking and xdr proc invocation into a common function

[J. Bruce Fields]

From: J. Bruce Fields <bfields at citi.umich.edu>

Since every invocation of xdr encode or decode functions takes the BKL now,
there's a lot of redundant lock_kernel/unlock_kernel pairs that we can pull out
into a common function.

Signed-off-by: J. Bruce Fields <bfields at citi.umich.edu>
---
 include/linux/sunrpc/xdr.h     |   11 +++++++++++
 net/sunrpc/auth.c              |   12 ++----------
 net/sunrpc/auth_gss/auth_gss.c |   20 +++++---------------
 3 files changed, 18 insertions(+), 25 deletions(-)

Uh, I'm also starting to feel kind of ridiculous adding these
lock_kernel/unlock_kernel's everywhere--at some point it seems better
just to do them all in one place.  But tastes differ, so I figured I'd
leave this change separate.  It could be folded into the previous patch
if that seems better....

--b.

diff --git a/include/linux/sunrpc/xdr.h b/include/linux/sunrpc/xdr.h
index 9e340fa..594e501 100644
--- a/include/linux/sunrpc/xdr.h
+++ b/include/linux/sunrpc/xdr.h
@@ -12,6 +12,7 @@
 #include <linux/uio.h>
 #include <asm/byteorder.h>
 #include <linux/scatterlist.h>
+#include <linux/smp_lock.h>
 
 /*
  * Buffer adjustment
@@ -35,6 +36,16 @@ struct xdr_netobj {
  */
 typedef int	(*kxdrproc_t)(void *rqstp, __be32 *data, void *obj);
 
+static inline int do_xdrproc(kxdrproc_t xdrproc, void *rqstp, __be32 *data, void *obj)
+{
+	int ret;
+
+	lock_kernel();
+	ret = xdrproc(rqstp, data, obj);
+	unlock_kernel();
+	return ret;
+}
+
 /*
  * Basic structure for transmission/reception of a client XDR message.
  * Features a header (for a linear buffer containing RPC headers
diff --git a/net/sunrpc/auth.c b/net/sunrpc/auth.c
index e04da66..6ad83c1 100644
--- a/net/sunrpc/auth.c
+++ b/net/sunrpc/auth.c
@@ -359,17 +359,13 @@ rpcauth_wrap_req(struct rpc_task *task, kxdrproc_t encode, void *rqstp,
 		__be32 *data, void *obj)
 {
 	struct rpc_cred *cred = task->tk_msg.rpc_cred;
-	int ret;
 
 	dprintk("RPC: %5u using %s cred %p to wrap rpc data\n",
 			task->tk_pid, cred->cr_ops->cr_name, cred);
 	if (cred->cr_ops->crwrap_req)
 		return cred->cr_ops->crwrap_req(task, encode, rqstp, data, obj);
 	/* By default, we encode the arguments normally. */
-	lock_kernel();
-	ret = encode(rqstp, data, obj);
-	unlock_kernel();
-	return ret;
+	return do_xdrproc(encode, rqstp, data, obj);
 }
 
 int
@@ -377,7 +373,6 @@ rpcauth_unwrap_resp(struct rpc_task *task, kxdrproc_t decode, void *rqstp,
 		__be32 *data, void *obj)
 {
 	struct rpc_cred *cred = task->tk_msg.rpc_cred;
-	int ret;
 
 	dprintk("RPC: %5u using %s cred %p to unwrap rpc data\n",
 			task->tk_pid, cred->cr_ops->cr_name, cred);
@@ -385,10 +380,7 @@ rpcauth_unwrap_resp(struct rpc_task *task, kxdrproc_t decode, void *rqstp,
 		return cred->cr_ops->crunwrap_resp(task, decode, rqstp,
 						   data, obj);
 	/* By default, we decode the arguments normally. */
-	lock_kernel();
-	ret = decode(rqstp, data, obj);
-	unlock_kernel();
-	return ret;
+	return do_xdrproc(decode, rqstp, data, obj);
 }
 
 int
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index a001973..35d5dc9 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -917,9 +917,7 @@ gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 	offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
 	*p++ = htonl(rqstp->rq_seqno);
 
-	lock_kernel();
-	status = encode(rqstp, p, obj);
-	unlock_kernel();
+	status = do_xdrproc(encode, rqstp, p, obj);
 	if (status)
 		return status;
 
@@ -1013,9 +1011,7 @@ gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
 	offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
 	*p++ = htonl(rqstp->rq_seqno);
 
-	lock_kernel();
-	status = encode(rqstp, p, obj);
-	unlock_kernel();
+	status = do_xdrproc(encode, rqstp, p, obj);
 	if (status)
 		return status;
 
@@ -1074,16 +1070,12 @@ gss_wrap_req(struct rpc_task *task,
 		/* The spec seems a little ambiguous here, but I think that not
 		 * wrapping context destruction requests makes the most sense.
 		 */
-		lock_kernel();
-		status = encode(rqstp, p, obj);
-		unlock_kernel();
+		status = do_xdrproc(encode, rqstp, p, obj);
 		goto out;
 	}
 	switch (gss_cred->gc_service) {
 		case RPC_GSS_SVC_NONE:
-			lock_kernel();
-			status = encode(rqstp, p, obj);
-			unlock_kernel();
+			status = do_xdrproc(encode, rqstp, p, obj);
 			break;
 		case RPC_GSS_SVC_INTEGRITY:
 			status = gss_wrap_req_integ(cred, ctx, encode,
@@ -1199,9 +1191,7 @@ gss_unwrap_resp(struct rpc_task *task,
 	task->tk_auth->au_rslack = task->tk_auth->au_verfsize + (p - savedp)
 						+ (savedlen - head->iov_len);
 out_decode:
-	lock_kernel();
-	status = decode(rqstp, p, obj);
-	unlock_kernel();
+	status = do_xdrproc(decode, rqstp, p, obj);
 out:
 	gss_put_ctx(ctx);
 	dprintk("RPC: %5u gss_unwrap_resp returning %d\n", task->tk_pid,
-- 
1.5.2.58.g98ee