[PATCH 6/7] nfsd: nfsd_check_obj_isreg() to use nfs error codes.

[NeilBrown <neilb@ownmail.net>]

From: NeilBrown <neil@brown.name>

There is no longer any value in having nfsd_check_obj_isreg() return
over-loaded error codes which are converted to nfs error codes.
So revert to directly returning the required nfs error code.

Also take the opportunity to avoid dereferencing the inode and determine
the type directly from the dentry.

We can now remove ELOOP from nfs_errtbl[] as it doesn't *really* mean
the same as nfserr_symlink.  We probably don't need EFTYPE either, but
there is a very good match of meaning, so let's leave it.

Signed-off-by: NeilBrown <neil@brown.name>
---
 fs/nfsd/nfs4proc.c | 36 ++++++++++++++++--------------------
 fs/nfsd/vfs.c      |  1 -
 2 files changed, 16 insertions(+), 21 deletions(-)

diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 0fd5a6411ed3..a6ba7618a307 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -223,20 +223,17 @@ do_open_permission(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfs
 	return fh_verify(rqstp, current_fh, S_IFREG, accmode);
 }
 
-static int nfsd_check_obj_isreg(struct dentry *child)
+static __be32 nfsd_check_obj_isreg(struct dentry *child)
 {
-	umode_t mode;
-
-	if (!child || !d_inode(child))
-		return -EFTYPE;
-	mode = d_inode(child)->i_mode;
-	if (S_ISREG(mode))
+	if (!child)
+		return nfserr_wrong_type;
+	if (d_is_reg(child))
 		return 0;
-	if (S_ISDIR(mode))
-		return -EISDIR;
-	if (S_ISLNK(mode))
-		return -ELOOP;
-	return -EFTYPE;
+	if (d_is_dir(child))
+		return nfserr_isdir;
+	if (d_is_symlink(child))
+		return nfserr_symlink;
+	return nfserr_wrong_type;
 }
 
 static void nfsd4_set_open_owner_reply_cache(struct nfsd4_compound_state *cstate, struct nfsd4_open *open, struct svc_fh *resfh)
@@ -388,18 +385,17 @@ nfsd4_create_file(struct svc_rqst *rqstp, struct svc_fh *fhp,
 					oflags,
 					open->op_iattr.ia_mode & S_IALLUGO);
 	if (IS_ERR(open->op_filp)) {
-		int hosterr = PTR_ERR(open->op_filp);
-
-		if (hosterr == -EFTYPE) {
+		status = nfserrno(PTR_ERR(open->op_filp));
+		if (status == nfserr_wrong_type) {
 			if (nfsd4_create_is_exclusive(open->op_createmode))
-				hosterr = -EEXIST;
+				status = nfserr_exist;
 			else
-				hosterr = nfsd_check_obj_isreg(parent.dentry);
+				status = nfsd_check_obj_isreg(parent.dentry);
 		}
-		status = nfserrno(hosterr);
-		open->op_filp = NULL;
 		if (status == nfserr_noent && create_status)
 			status = create_status;
+
+		open->op_filp = NULL;
 		dput(parent.dentry);
 		goto out;
 	}
@@ -558,7 +554,7 @@ do_open_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, stru
 	}
 	if (status)
 		goto out;
-	status = nfserrno(nfsd_check_obj_isreg((*resfh)->fh_dentry));
+	status = nfsd_check_obj_isreg((*resfh)->fh_dentry);
 	if (status)
 		goto out;
 
diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index f9131827d391..8def58e92a8e 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -106,7 +106,6 @@ nfserrno(int errno)
 		{ nfserr_perm, -ENOKEY },
 		{ nfserr_no_grace, -ENOGRACE},
 		{ nfserr_io, -EBADMSG },
-		{ nfserr_symlink, -ELOOP },
 		{ nfserr_wrong_type, -EFTYPE },
 	};
 	int	i;
-- 
2.50.0.107.gf914562f5916.dirty