nfsd41: make sure nfs server process OPEN with EXCLUSIVE4_1 correctly

The NFS server uses nfsd_create_v3 to handle EXCLUSIVE4_1 opens, but
that function is not prepared to handle them.

Rename nfsd_create_v3() to do_nfsd_create(), and add handling of
EXCLUSIVE4_1.
Signed-off-by: Mi Jinlong <mijinlong@cn.fujitsu.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfs3proc.c

@@ -245,7 +245,7 @@ nfsd3_proc_create(struct svc_rqst *rqstp, struct nfsd3_createargs *argp,
 	}
 
 	/* Now create the file and set attributes */
-	nfserr = nfsd_create_v3(rqstp, dirfhp, argp->name, argp->len,
+	nfserr = do_nfsd_create(rqstp, dirfhp, argp->name, argp->len,
 				attr, newfhp,
 				argp->createmode, argp->verf, NULL, NULL);
 

fs/nfsd/nfs4proc.c

@@ -196,9 +196,9 @@ do_open_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_o
 
 		/*
 		 * Note: create modes (UNCHECKED,GUARDED...) are the same
-		 * in NFSv4 as in v3.
+		 * in NFSv4 as in v3 except EXCLUSIVE4_1.
 		 */
-		status = nfsd_create_v3(rqstp, current_fh, open->op_fname.data,
+		status = do_nfsd_create(rqstp, current_fh, open->op_fname.data,
 					open->op_fname.len, &open->op_iattr,
 					&resfh, open->op_createmode,
 					(u32 *)open->op_verf.data,

fs/nfsd/vfs.c

@@ -1337,11 +1337,18 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 }
 
 #ifdef CONFIG_NFSD_V3
+
+static inline int nfsd_create_is_exclusive(int createmode)
+{
+	return createmode == NFS3_CREATE_EXCLUSIVE
+	       || createmode == NFS4_CREATE_EXCLUSIVE4_1;
+}
+
 /*
- * NFSv3 version of nfsd_create
+ * NFSv3 and NFSv4 version of nfsd_create
  */
 __be32
-nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
+do_nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp,
 		char *fname, int flen, struct iattr *iap,
 		struct svc_fh *resfhp, int createmode, u32 *verifier,
 	        int *truncp, int *created)
@@ -1386,7 +1393,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 	if (err)
 		goto out;
 
-	if (createmode == NFS3_CREATE_EXCLUSIVE) {
+	if (nfsd_create_is_exclusive(createmode)) {
 		/* solaris7 gets confused (bugid 4218508) if these have
 		 * the high bit set, so just clear the high bits. If this is
 		 * ever changed to use different attrs for storing the
@@ -1427,6 +1434,11 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 			    && dchild->d_inode->i_atime.tv_sec == v_atime
 			    && dchild->d_inode->i_size  == 0 )
 				break;
+		case NFS4_CREATE_EXCLUSIVE4_1:
+			if (   dchild->d_inode->i_mtime.tv_sec == v_mtime
+			    && dchild->d_inode->i_atime.tv_sec == v_atime
+			    && dchild->d_inode->i_size  == 0 )
+				goto set_attr;
 			 /* fallthru */
 		case NFS3_CREATE_GUARDED:
 			err = nfserr_exist;
@@ -1445,7 +1457,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, struct svc_fh *fhp,
 
 	nfsd_check_ignore_resizing(iap);
 
-	if (createmode == NFS3_CREATE_EXCLUSIVE) {
+	if (nfsd_create_is_exclusive(createmode)) {
 		/* Cram the verifier into atime/mtime */
 		iap->ia_valid = ATTR_MTIME|ATTR_ATIME
 			| ATTR_MTIME_SET|ATTR_ATIME_SET;

fs/nfsd/vfs.h

@@ -58,7 +58,7 @@ __be32		nfsd_create(struct svc_rqst *, struct svc_fh *,
 				int type, dev_t rdev, struct svc_fh *res);
 #ifdef CONFIG_NFSD_V3
 __be32		nfsd_access(struct svc_rqst *, struct svc_fh *, u32 *, u32 *);
-__be32		nfsd_create_v3(struct svc_rqst *, struct svc_fh *,
+__be32		do_nfsd_create(struct svc_rqst *, struct svc_fh *,
 				char *name, int len, struct iattr *attrs,
 				struct svc_fh *res, int createmode,
 				u32 *verifier, int *truncp, int *created);