nfsd: Headers Independence and include cleanups

* Add includes that are directly used by headers
* Remove includes that are not needed

These are the changes made:

[xdr.h]
struct nfsd_readdirres has an embedded struct readdir_cd from nfsd.h
fixing that we can drop other includes

[xdr4.h]
embedded types defined both at state.h and nfsd.h

[syscall.h]
After export.h fix none of these stuff is needed.
fix extra space in # include <> statement

[stats.h]
does not need <linux/nfs4.h> but was export to user-mode
so I don't touch it

[state.h]
embedded types from nfsfh.h like struct knfsd_fh. bringing that
eliminates the need for all other includes

[nfsfh.h]
directly manipulating types from sunrpc/svc.h.
Removed Other unused headers.

[nfsd.h]
removed unused headers include

[export.h]
lots of sunrpc/svc.h types and a single prototype declaration
with pointer from nfsfh.h, but all users of export.h do need
nfsfh.h any way. remove now un-needed include.

[const.h]
Unfixed (not independent)

[cache.h]
could do with a forward declaration of "struct svc_rqst;"
from sunrpc/svc.h but all users absolutely will need
sunrpc/svc.h it is easier overall this way.
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>

include/linux/nfsd/cache.h

@@ -10,8 +10,7 @@
 #ifndef NFSCACHE_H
 #define NFSCACHE_H
 
-#include <linux/in.h>
-#include <linux/uio.h>
+#include <linux/sunrpc/svc.h>
 
 /*
  * Representation of a reply cache entry.

include/linux/nfsd/export.h

@@ -12,7 +12,7 @@
 
 # include <linux/types.h>
 #ifdef __KERNEL__
-# include <linux/in.h>
+# include <linux/nfsd/nfsfh.h>
 #endif
 
 /*

include/linux/nfsd/nfsd.h

@@ -11,13 +11,9 @@
 #define LINUX_NFSD_NFSD_H
 
 #include <linux/types.h>
-#include <linux/unistd.h>
-#include <linux/fs.h>
-#include <linux/posix_acl.h>
 #include <linux/mount.h>
 
 #include <linux/nfsd/debug.h>
-#include <linux/nfsd/nfsfh.h>
 #include <linux/nfsd/export.h>
 #include <linux/nfsd/stats.h>
 /*

include/linux/nfsd/nfsfh.h

@@ -16,8 +16,7 @@
 
 # include <linux/types.h>
 #ifdef __KERNEL__
-# include <linux/string.h>
-# include <linux/fs.h>
+# include <linux/sunrpc/svc.h>
 #endif
 #include <linux/nfsd/const.h>
 

include/linux/nfsd/state.h

@@ -37,9 +37,7 @@
 #ifndef _NFSD4_STATE_H
 #define _NFSD4_STATE_H
 
-#include <linux/list.h>
-#include <linux/kref.h>
-#include <linux/sunrpc/clnt.h>
+#include <linux/nfsd/nfsfh.h>
 
 typedef struct {
 	u32             cl_boot;

include/linux/nfsd/syscall.h

@@ -9,14 +9,8 @@
 #ifndef NFSD_SYSCALL_H
 #define NFSD_SYSCALL_H
 
-# include <linux/types.h>
-#ifdef __KERNEL__
-# include <linux/in.h>
-#endif 
-#include <linux/posix_types.h>
-#include <linux/nfsd/const.h>
+#include <linux/types.h>
 #include <linux/nfsd/export.h>
-#include <linux/nfsd/nfsfh.h>
 
 /*
  * Version of the syscall interface

include/linux/nfsd/xdr.h

@@ -7,9 +7,8 @@
 #ifndef LINUX_NFSD_H
 #define LINUX_NFSD_H
 
-#include <linux/fs.h>
 #include <linux/vfs.h>
-#include <linux/nfs.h>
+#include <linux/nfsd/nfsd.h>
 
 struct nfsd_fhandle {
 	struct svc_fh		fh;

include/linux/nfsd/xdr4.h

@@ -39,7 +39,8 @@
 #ifndef _LINUX_NFSD_XDR4_H
 #define _LINUX_NFSD_XDR4_H
 
-#include <linux/nfs4.h>
+#include <linux/nfsd/state.h>
+#include <linux/nfsd/nfsd.h>
 
 #define NFSD4_MAX_TAGLEN	128
 #define XDR_LEN(n)                     (((n) + 3) & ~3)