zfs: implement AT_RENAME_NOREPLACE

Reviewed by:	markj
Tested by:	pho
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D55539

sys/contrib/openzfs/include/os/freebsd/zfs/sys/zfs_vnops_os.h

@@ -42,8 +42,8 @@ extern int zfs_rmdir(znode_t *dzp, const char *name, znode_t *cwd,
 extern int zfs_setattr(znode_t *zp, vattr_t *vap, int flag, cred_t *cr,
     zidmap_t *mnt_ns);
 extern int zfs_rename(znode_t *sdzp, const char *snm, znode_t *tdzp,
-    const char *tnm, cred_t *cr, int flags, uint64_t rflags, vattr_t *wo_vap,
-    zidmap_t *mnt_ns);
+    const char *tnm, cred_t *cr, int flags, uint64_t rflags, u_int at_flags,
+    vattr_t *wo_vap, zidmap_t *mnt_ns);
 extern int zfs_symlink(znode_t *dzp, const char *name, vattr_t *vap,
     const char *link, znode_t **zpp, cred_t *cr, int flags, zidmap_t *mnt_ns);
 extern int zfs_link(znode_t *tdzp, znode_t *sp,

sys/contrib/openzfs/module/os/freebsd/zfs/zfs_vnops_os.c

@@ -3256,7 +3256,7 @@ zfs_rename_check(znode_t *szp, znode_t *sdzp, znode_t *tdzp)
 static int
 zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
     vnode_t *tdvp, vnode_t **tvpp, struct componentname *tcnp,
-    cred_t *cr);
+    cred_t *cr, u_int at_flags);
 
 /*
  * Move an entry from the provided source directory to the target
@@ -3267,6 +3267,7 @@ zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
  *		tdvp	- Target directory to contain the "new entry".
  *		tcnp	- New entry name.
  *		cr	- credentials of caller.
+ *		at_flags - AT_RENAME_*
  *	INOUT:	svpp	- Source file
  *		tvpp	- Target file, may point to NULL initially
  *
@@ -3278,7 +3279,7 @@ zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
 static int
 zfs_do_rename(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
     vnode_t *tdvp, vnode_t **tvpp, struct componentname *tcnp,
-    cred_t *cr)
+    cred_t *cr, u_int at_flags)
 {
 	int	error;
 
@@ -3307,7 +3308,8 @@ zfs_do_rename(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
 		return (error);
 	}
 
-	error = zfs_do_rename_impl(sdvp, svpp, scnp, tdvp, tvpp, tcnp, cr);
+	error = zfs_do_rename_impl(sdvp, svpp, scnp, tdvp, tvpp, tcnp, cr,
+	    at_flags);
 	VOP_UNLOCK(sdvp);
 	VOP_UNLOCK(*svpp);
 out:
@@ -3322,7 +3324,7 @@ zfs_do_rename(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
 static int
 zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
     vnode_t *tdvp, vnode_t **tvpp, struct componentname *tcnp,
-    cred_t *cr)
+    cred_t *cr, u_int at_flags)
 {
 	dmu_tx_t	*tx;
 	zfsvfs_t	*zfsvfs;
@@ -3431,6 +3433,11 @@ zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
 	 * Does target exist?
 	 */
 	if (tzp) {
+		if ((at_flags & AT_RENAME_NOREPLACE) != 0) {
+			error = SET_ERROR(EEXIST);
+			goto out;
+		}
+
 		/*
 		 * Source and target must be the same type.
 		 */
@@ -3551,7 +3558,8 @@ zfs_do_rename_impl(vnode_t *sdvp, vnode_t **svpp, struct componentname *scnp,
 
 int
 zfs_rename(znode_t *sdzp, const char *sname, znode_t *tdzp, const char *tname,
-    cred_t *cr, int flags, uint64_t rflags, vattr_t *wo_vap, zidmap_t *mnt_ns)
+    cred_t *cr, int flags, uint64_t rflags, u_int at_flags, vattr_t *wo_vap,
+    zidmap_t *mnt_ns)
 {
 	struct componentname scn, tcn;
 	vnode_t *sdvp, *tdvp;
@@ -3583,7 +3591,8 @@ zfs_rename(znode_t *sdzp, const char *sname, znode_t *tdzp, const char *tname,
 		goto fail;
 	}
 
-	error = zfs_do_rename(sdvp, &svp, &scn, tdvp, &tvp, &tcn, cr);
+	error = zfs_do_rename(sdvp, &svp, &scn, tdvp, &tvp, &tcn, cr,
+	    at_flags);
 fail:
 	if (svp != NULL)
 		vrele(svp);
@@ -5527,12 +5536,12 @@ zfs_freebsd_rename(struct vop_rename_args *ap)
 	}
 #endif
 
-	if (error == 0 && ap->a_flags != 0)
+	if (error == 0 && (ap->a_flags & ~(AT_RENAME_NOREPLACE)) != 0)
 		error = EOPNOTSUPP;
 
 	if (error == 0) {
 		error = zfs_do_rename(fdvp, &fvp, ap->a_fcnp, tdvp, &tvp,
-		    ap->a_tcnp, ap->a_fcnp->cn_cred);
+		    ap->a_tcnp, ap->a_fcnp->cn_cred, ap->a_flags);
 		vrele(fdvp);
 		vrele(fvp);
 		vrele(tdvp);

sys/contrib/openzfs/module/zfs/zfs_replay.c

@@ -710,7 +710,7 @@ do_zfs_replay_rename(zfsvfs_t *zfsvfs, _lr_rename_t *lr, char *sname,
 	    wo_vap, zfs_init_idmap);
 #else
 	error = zfs_rename(sdzp, sname, tdzp, tname, kcred, vflg, rflags,
-	    wo_vap, NULL);
+	    0, wo_vap, NULL);
 #endif
 
 	zrele(tdzp);