sunrpc: add a generic rq_flags field to svc_rqst and move rq_secure to it

In a later patch, we're going to need some atomic bit flags. Since that
field will need to be an unsigned long, we mitigate that space
consumption by migrating some other bitflags to the new field. Start
with the rq_secure flag.
Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfscache.c

@@ -490,7 +490,7 @@ nfsd_cache_lookup(struct svc_rqst *rqstp)
 	/* From the hall of fame of impractical attacks:
 	 * Is this a user who tries to snoop on the cache? */
 	rtn = RC_DOIT;
-	if (!rqstp->rq_secure && rp->c_secure)
+	if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && rp->c_secure)
 		goto out;
 
 	/* Compose RPC reply header */
@@ -579,7 +579,7 @@ nfsd_cache_update(struct svc_rqst *rqstp, int cachetype, __be32 *statp)
 	spin_lock(&b->cache_lock);
 	drc_mem_usage += bufsize;
 	lru_put_end(b, rp);
-	rp->c_secure = rqstp->rq_secure;
+	rp->c_secure = test_bit(RQ_SECURE, &rqstp->rq_flags);
 	rp->c_type = cachetype;
 	rp->c_state = RC_DONE;
 	spin_unlock(&b->cache_lock);

fs/nfsd/nfsfh.c

@@ -86,7 +86,7 @@ static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
 	int flags = nfsexp_flags(rqstp, exp);
 
 	/* Check if the request originated from a secure port. */
-	if (!rqstp->rq_secure && !(flags & NFSEXP_INSECURE_PORT)) {
+	if (!test_bit(RQ_SECURE, &rqstp->rq_flags) && !(flags & NFSEXP_INSECURE_PORT)) {
 		RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
 		dprintk("nfsd: request from insecure port %s!\n",
 		        svc_print_addr(rqstp, buf, sizeof(buf)));

include/linux/sunrpc/svc.h

@@ -253,8 +253,8 @@ struct svc_rqst {
 	u32			rq_vers;	/* program version */
 	u32			rq_proc;	/* procedure number */
 	u32			rq_prot;	/* IP protocol */
-	unsigned short
-				rq_secure  : 1;	/* secure port */
+#define	RQ_SECURE	(0)			/* secure port */
+	unsigned long		rq_flags;	/* flags field */
 	unsigned short		rq_local   : 1;	/* local request */
 
 	void *			rq_argp;	/* decoded arguments */

include/trace/events/sunrpc.h

@@ -412,6 +412,10 @@ TRACE_EVENT(xs_tcp_data_recv,
 			__entry->copied, __entry->reclen, __entry->offset)
 );
 
+#define show_rqstp_flags(flags)				\
+	__print_flags(flags, "|",			\
+		{ (1UL << RQ_SECURE),	"RQ_SECURE"})
+
 TRACE_EVENT(svc_recv,
 	TP_PROTO(struct svc_rqst *rqst, int status),
 
@@ -421,16 +425,19 @@ TRACE_EVENT(svc_recv,
 		__field(struct sockaddr *, addr)
 		__field(__be32, xid)
 		__field(int, status)
+		__field(unsigned long, flags)
 	),
 
 	TP_fast_assign(
 		__entry->addr = (struct sockaddr *)&rqst->rq_addr;
 		__entry->xid = status > 0 ? rqst->rq_xid : 0;
 		__entry->status = status;
+		__entry->flags = rqst->rq_flags;
 	),
 
-	TP_printk("addr=%pIScp xid=0x%x status=%d", __entry->addr,
-			be32_to_cpu(__entry->xid), __entry->status)
+	TP_printk("addr=%pIScp xid=0x%x status=%d flags=%s", __entry->addr,
+			be32_to_cpu(__entry->xid), __entry->status,
+			show_rqstp_flags(__entry->flags))
 );
 
 DECLARE_EVENT_CLASS(svc_rqst_status,
@@ -444,6 +451,7 @@ DECLARE_EVENT_CLASS(svc_rqst_status,
 		__field(__be32, xid)
 		__field(int, dropme)
 		__field(int, status)
+		__field(unsigned long, flags)
 	),
 
 	TP_fast_assign(
@@ -451,11 +459,12 @@ DECLARE_EVENT_CLASS(svc_rqst_status,
 		__entry->xid = rqst->rq_xid;
 		__entry->dropme = (int)rqst->rq_dropme;
 		__entry->status = status;
+		__entry->flags = rqst->rq_flags;
 	),
 
-	TP_printk("addr=%pIScp rq_xid=0x%x dropme=%d status=%d",
+	TP_printk("addr=%pIScp rq_xid=0x%x dropme=%d status=%d flags=%s",
 		__entry->addr, be32_to_cpu(__entry->xid), __entry->dropme,
-		__entry->status)
+		__entry->status, show_rqstp_flags(__entry->flags))
 );
 
 DEFINE_EVENT(svc_rqst_status, svc_process,

net/sunrpc/svc_xprt.c

@@ -797,7 +797,10 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 
 	clear_bit(XPT_OLD, &xprt->xpt_flags);
 
-	rqstp->rq_secure = xprt->xpt_ops->xpo_secure_port(rqstp);
+	if (xprt->xpt_ops->xpo_secure_port(rqstp))
+		set_bit(RQ_SECURE, &rqstp->rq_flags);
+	else
+		clear_bit(RQ_SECURE, &rqstp->rq_flags);
 	rqstp->rq_chandle.defer = svc_defer;
 	rqstp->rq_xid = svc_getu32(&rqstp->rq_arg.head[0]);