NFSD: Replace dprintk() call site in fh_verify()

Record permission errors in the trace log. Note that the new trace
event is conditional, so it will only record non-zero return values
from nfsd_permission().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>

fs/nfsd/nfsfh.c

@@ -392,13 +392,7 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, umode_t type, int access)
 skip_pseudoflavor_check:
 	/* Finally, check access permissions. */
 	error = nfsd_permission(rqstp, exp, dentry, access);
-
-	if (error) {
-		dprintk("fh_verify: %pd2 permission failure, "
-			"acc=%x, error=%d\n",
-			dentry,
-			access, ntohl(error));
-	}
+	trace_nfsd_fh_verify_err(rqstp, fhp, type, access, error);
 out:
 	if (error == nfserr_stale)
 		nfsd_stats_fh_stale_inc(exp);

fs/nfsd/trace.h

@@ -195,7 +195,7 @@ TRACE_EVENT(nfsd_fh_verify,
 		__sockaddr(client, rqstp->rq_xprt->xpt_remotelen)
 		__field(u32, xid)
 		__field(u32, fh_hash)
-		__field(void *, inode)
+		__field(const void *, inode)
 		__field(unsigned long, type)
 		__field(unsigned long, access)
 	),
@@ -211,13 +211,55 @@ TRACE_EVENT(nfsd_fh_verify,
 		__entry->type = type;
 		__entry->access = access;
 	),
-	TP_printk("xid=0x%08x fh_hash=0x%08x inode=%p type=%s access=%s",
-		__entry->xid, __entry->fh_hash, __entry->inode,
+	TP_printk("xid=0x%08x fh_hash=0x%08x type=%s access=%s",
+		__entry->xid, __entry->fh_hash,
 		show_fs_file_type(__entry->type),
 		show_nfsd_may_flags(__entry->access)
 	)
 );
 
+TRACE_EVENT_CONDITION(nfsd_fh_verify_err,
+	TP_PROTO(
+		const struct svc_rqst *rqstp,
+		const struct svc_fh *fhp,
+		umode_t type,
+		int access,
+		__be32 error
+	),
+	TP_ARGS(rqstp, fhp, type, access, error),
+	TP_CONDITION(error),
+	TP_STRUCT__entry(
+		__field(unsigned int, netns_ino)
+		__sockaddr(server, rqstp->rq_xprt->xpt_remotelen)
+		__sockaddr(client, rqstp->rq_xprt->xpt_remotelen)
+		__field(u32, xid)
+		__field(u32, fh_hash)
+		__field(const void *, inode)
+		__field(unsigned long, type)
+		__field(unsigned long, access)
+		__field(int, error)
+	),
+	TP_fast_assign(
+		__entry->netns_ino = SVC_NET(rqstp)->ns.inum;
+		__assign_sockaddr(server, &rqstp->rq_xprt->xpt_local,
+		       rqstp->rq_xprt->xpt_locallen);
+		__assign_sockaddr(client, &rqstp->rq_xprt->xpt_remote,
+				  rqstp->rq_xprt->xpt_remotelen);
+		__entry->xid = be32_to_cpu(rqstp->rq_xid);
+		__entry->fh_hash = knfsd_fh_hash(&fhp->fh_handle);
+		__entry->inode = d_inode(fhp->fh_dentry);
+		__entry->type = type;
+		__entry->access = access;
+		__entry->error = be32_to_cpu(error);
+	),
+	TP_printk("xid=0x%08x fh_hash=0x%08x type=%s access=%s error=%d",
+		__entry->xid, __entry->fh_hash,
+		show_fs_file_type(__entry->type),
+		show_nfsd_may_flags(__entry->access),
+		__entry->error
+	)
+);
+
 DECLARE_EVENT_CLASS(nfsd_fh_err_class,
 	TP_PROTO(struct svc_rqst *rqstp,
 		 struct svc_fh	*fhp,