[PATCH 6/9] NFSD: Move struct readdir_cd

[Chuck Lever <cel@kernel.org>]

struct readdir_cd is part of the VFS readdir API, but it lives in
nfsd.h, the subsystem's catch-all header, rather than alongside that
API. That forces vfs.h to include nfsd.h solely to declare readdir_cd
for its nfsd_readdir() prototype, a layering inversion since vfs.h is
the lower-level shim.

Relocate readdir_cd to vfs.h, just below the nfsd_filldir_t callback
typedef. vfs.h then defines the struct itself and no longer includes
nfsd.h. The xdr headers that embed readdir_cd by value include vfs.h
to obtain the definition. This prepares the ground for dropping nfsd.h
from more files.

Signed-off-by: Chuck Lever <cel@kernel.org>
---
 fs/nfsd/nfsd.h | 4 ----
 fs/nfsd/vfs.h  | 5 ++++-
 fs/nfsd/xdr.h  | 1 +
 fs/nfsd/xdr3.h | 1 +
 fs/nfsd/xdr4.h | 2 +-
 5 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h
index b35e9a9a112d..0503ee0e1bbe 100644
--- a/fs/nfsd/nfsd.h
+++ b/fs/nfsd/nfsd.h
@@ -47,10 +47,6 @@ enum {
 	NFSSVC_MAXBLKSIZE       = RPCSVC_MAXPAYLOAD,
 };
 
-struct readdir_cd {
-	__be32			err;	/* 0, nfserr, or nfserr_eof */
-};
-
 /* Maximum number of operations per session compound */
 #define NFSD_MAX_OPS_PER_COMPOUND	200
 
diff --git a/fs/nfsd/vfs.h b/fs/nfsd/vfs.h
index e09ea04a51b9..4af2ff9e9dfe 100644
--- a/fs/nfsd/vfs.h
+++ b/fs/nfsd/vfs.h
@@ -9,7 +9,6 @@
 #include <linux/fs.h>
 #include <linux/posix_acl.h>
 #include "nfsfh.h"
-#include "nfsd.h"
 
 /*
  * Flags for nfsd_permission
@@ -45,6 +44,10 @@ struct nfsd_file;
  */
 typedef int (*nfsd_filldir_t)(void *, const char *, int, loff_t, u64, unsigned);
 
+struct readdir_cd {
+	__be32			err;	/* nfs_ok, nfserr, or nfserr_eof */
+};
+
 /* nfsd/vfs.c */
 struct nfsd_attrs {
 	struct iattr		*na_iattr;	/* input */
diff --git a/fs/nfsd/xdr.h b/fs/nfsd/xdr.h
index 852f71580bd0..df540c940cef 100644
--- a/fs/nfsd/xdr.h
+++ b/fs/nfsd/xdr.h
@@ -7,6 +7,7 @@
 #include <linux/vfs.h>
 #include "nfsd.h"
 #include "nfsfh.h"
+#include "vfs.h"
 
 struct nfsd_fhandle {
 	struct svc_fh		fh;
diff --git a/fs/nfsd/xdr3.h b/fs/nfsd/xdr3.h
index a7c9714b0b0e..344203874b4c 100644
--- a/fs/nfsd/xdr3.h
+++ b/fs/nfsd/xdr3.h
@@ -9,6 +9,7 @@
 #define _LINUX_NFSD_XDR3_H
 
 #include "xdr.h"
+#include "vfs.h"
 
 struct nfsd3_sattrargs {
 	struct svc_fh		fh;
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index 805c7122eb93..0ec0f43b1a87 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -38,7 +38,7 @@
 #define _LINUX_NFSD_XDR4_H
 
 #include "state.h"
-#include "nfsd.h"
+#include "vfs.h"
 
 #define NFSD4_MAX_TAGLEN	128
 #define XDR_LEN(n)                     (((n) + 3) & ~3)
-- 
2.54.0