include/linux/sunrpc/xdr.h - LeafOS-Devices/android_kernel_samsung_gta4xl - Gitiles

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * XDR standard data types and function declarations
  *
  * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
  *
  * Based on:
  *   RFC 4506 "XDR: External Data Representation Standard", May 2006
  */

 #ifndef _SUNRPC_XDR_H_
 #define _SUNRPC_XDR_H_

 #ifdef __KERNEL__

 #include <linux/uio.h>
 #include <asm/byteorder.h>
 #include <asm/unaligned.h>
 #include <linux/scatterlist.h>

 struct rpc_rqst;

 /*
  * Buffer adjustment
  */
 #define XDR_QUADLEN(l)		(((l) + 3) >> 2)

 /*
  * Generic opaque `network object.'
  */
 #define XDR_MAX_NETOBJ		1024
 struct xdr_netobj {
 	unsigned int		len;
 	u8 *			data;
 };

 /*
  * Basic structure for transmission/reception of a client XDR message.
  * Features a header (for a linear buffer containing RPC headers
  * and the data payload for short messages), and then an array of
  * pages.
  * The tail iovec allows you to append data after the page array. Its
  * main interest is for appending padding to the pages in order to
  * satisfy the int_32-alignment requirements in RFC1832.
  *
  * For the future, we might want to string several of these together
  * in a list if anybody wants to make use of NFSv4 COMPOUND
  * operations and/or has a need for scatter/gather involving pages.
  */
 struct xdr_buf {
 	struct kvec	head[1],	/* RPC header + non-page data */
 			tail[1];	/* Appended after page data */

 	struct page **	pages;		/* Array of pages */
 	unsigned int	page_base,	/* Start of page data */
 			page_len,	/* Length of page data */
 			flags;		/* Flags for data disposition */
 #define XDRBUF_READ		0x01		/* target of file read */
 #define XDRBUF_WRITE		0x02		/* source of file write */

 	unsigned int	buflen,		/* Total length of storage buffer */
 			len;		/* Length of XDR encoded message */
 };

 static inline void
 xdr_buf_init(struct xdr_buf *buf, void *start, size_t len)
 {
 	buf->head[0].iov_base = start;
 	buf->head[0].iov_len = len;
 	buf->tail[0].iov_len = 0;
 	buf->page_len = 0;
 	buf->flags = 0;
 	buf->len = 0;
 	buf->buflen = len;
 }

 /*
  * pre-xdr'ed macros.
  */

 #define	xdr_zero	cpu_to_be32(0)
 #define	xdr_one		cpu_to_be32(1)
 #define	xdr_two		cpu_to_be32(2)

 #define	rpc_success		cpu_to_be32(RPC_SUCCESS)
 #define	rpc_prog_unavail	cpu_to_be32(RPC_PROG_UNAVAIL)
 #define	rpc_prog_mismatch	cpu_to_be32(RPC_PROG_MISMATCH)
 #define	rpc_proc_unavail	cpu_to_be32(RPC_PROC_UNAVAIL)
 #define	rpc_garbage_args	cpu_to_be32(RPC_GARBAGE_ARGS)
 #define	rpc_system_err		cpu_to_be32(RPC_SYSTEM_ERR)
 #define	rpc_drop_reply		cpu_to_be32(RPC_DROP_REPLY)

 #define	rpc_auth_ok		cpu_to_be32(RPC_AUTH_OK)
 #define	rpc_autherr_badcred	cpu_to_be32(RPC_AUTH_BADCRED)
 #define	rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
 #define	rpc_autherr_badverf	cpu_to_be32(RPC_AUTH_BADVERF)
 #define	rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
 #define	rpc_autherr_tooweak	cpu_to_be32(RPC_AUTH_TOOWEAK)
 #define	rpcsec_gsserr_credproblem	cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
 #define	rpcsec_gsserr_ctxproblem	cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
 #define	rpc_autherr_oldseqnum	cpu_to_be32(101)

 /*
  * Miscellaneous XDR helper functions
  */
 __be32 *xdr_encode_opaque_fixed(__be32 *p, const void *ptr, unsigned int len);
 __be32 *xdr_encode_opaque(__be32 *p, const void *ptr, unsigned int len);
 __be32 *xdr_encode_string(__be32 *p, const char *s);
 __be32 *xdr_decode_string_inplace(__be32 *p, char **sp, unsigned int *lenp,
 			unsigned int maxlen);
 __be32 *xdr_encode_netobj(__be32 *p, const struct xdr_netobj *);
 __be32 *xdr_decode_netobj(__be32 *p, struct xdr_netobj *);

 void	xdr_inline_pages(struct xdr_buf *, unsigned int,
 			 struct page **, unsigned int, unsigned int);
 void	xdr_terminate_string(struct xdr_buf *, const u32);

 static inline __be32 *xdr_encode_array(__be32 *p, const void *s, unsigned int len)
 {
 	return xdr_encode_opaque(p, s, len);
 }

 /*
  * Decode 64bit quantities (NFSv3 support)
  */
 static inline __be32 *
 xdr_encode_hyper(__be32 *p, __u64 val)
 {
 	put_unaligned_be64(val, p);
 	return p + 2;
 }

 static inline __be32 *
 xdr_decode_hyper(__be32 *p, __u64 *valp)
 {
 	*valp = get_unaligned_be64(p);
 	return p + 2;
 }

 static inline __be32 *
 xdr_decode_opaque_fixed(__be32 *p, void *ptr, unsigned int len)
 {
 	memcpy(ptr, p, len);
 	return p + XDR_QUADLEN(len);
 }

 /*
  * Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
  */
 static inline int
 xdr_adjust_iovec(struct kvec *iov, __be32 *p)
 {
 	return iov->iov_len = ((u8 *) p - (u8 *) iov->iov_base);
 }

 /*
  * XDR buffer helper functions
  */
 extern void xdr_shift_buf(struct xdr_buf *, size_t);
 extern void xdr_buf_from_iov(struct kvec *, struct xdr_buf *);
 extern int xdr_buf_subsegment(struct xdr_buf *, struct xdr_buf *, unsigned int, unsigned int);
 extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
 extern int xdr_buf_read_netobj(struct xdr_buf *, struct xdr_netobj *, unsigned int);
 extern int read_bytes_from_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);
 extern int write_bytes_to_xdr_buf(struct xdr_buf *, unsigned int, void *, unsigned int);

 /*
  * Helper structure for copying from an sk_buff.
  */
 struct xdr_skb_reader {
 	struct sk_buff	*skb;
 	unsigned int	offset;
 	size_t		count;
 	__wsum		csum;
 };

 typedef size_t (*xdr_skb_read_actor)(struct xdr_skb_reader *desc, void *to, size_t len);

 size_t xdr_skb_read_bits(struct xdr_skb_reader *desc, void *to, size_t len);
 extern int csum_partial_copy_to_xdr(struct xdr_buf *, struct sk_buff *);
 extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
 		struct xdr_skb_reader *, xdr_skb_read_actor);

 extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
 extern int xdr_decode_word(struct xdr_buf *, unsigned int, u32 *);

 struct xdr_array2_desc;
 typedef int (*xdr_xcode_elem_t)(struct xdr_array2_desc *desc, void *elem);
 struct xdr_array2_desc {
 	unsigned int elem_size;
 	unsigned int array_len;
 	unsigned int array_maxlen;
 	xdr_xcode_elem_t xcode;
 };

 extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
 			     struct xdr_array2_desc *desc);
 extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
 			     struct xdr_array2_desc *desc);
 extern void _copy_from_pages(char *p, struct page **pages, size_t pgbase,
 			     size_t len);

 /*
  * Provide some simple tools for XDR buffer overflow-checking etc.
  */
 struct xdr_stream {
 	__be32 *p;		/* start of available buffer */
 	struct xdr_buf *buf;	/* XDR buffer to read/write */

 	__be32 *end;		/* end of available buffer space */
 	struct kvec *iov;	/* pointer to the current kvec */
 	struct kvec scratch;	/* Scratch buffer */
 	struct page **page_ptr;	/* pointer to the current page */
 	unsigned int nwords;	/* Remaining decode buffer length */
 };

 /*
  * These are the xdr_stream style generic XDR encode and decode functions.
  */
 typedef void	(*kxdreproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
 		const void *obj);
 typedef int	(*kxdrdproc_t)(struct rpc_rqst *rqstp, struct xdr_stream *xdr,
 		void *obj);

 extern void xdr_init_encode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 extern __be32 *xdr_reserve_space(struct xdr_stream *xdr, size_t nbytes);
 extern void xdr_commit_encode(struct xdr_stream *xdr);
 extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
 extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
 extern void xdr_write_pages(struct xdr_stream *xdr, struct page **pages,
 		unsigned int base, unsigned int len);
 extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
 extern void xdr_init_decode(struct xdr_stream *xdr, struct xdr_buf *buf, __be32 *p);
 extern void xdr_init_decode_pages(struct xdr_stream *xdr, struct xdr_buf *buf,
 		struct page **pages, unsigned int len);
 extern void xdr_set_scratch_buffer(struct xdr_stream *xdr, void *buf, size_t buflen);
 extern __be32 *xdr_inline_decode(struct xdr_stream *xdr, size_t nbytes);
 extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
 extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
 extern int xdr_process_buf(struct xdr_buf *buf, unsigned int offset, unsigned int len, int (*actor)(struct scatterlist *, void *), void *data);

 /**
  * xdr_stream_remaining - Return the number of bytes remaining in the stream
  * @xdr: pointer to struct xdr_stream
  *
  * Return value:
  *   Number of bytes remaining in @xdr before xdr->end
  */
 static inline size_t
 xdr_stream_remaining(const struct xdr_stream *xdr)
 {
 	return xdr->nwords << 2;
 }

 ssize_t xdr_stream_decode_string_dup(struct xdr_stream *xdr, char **str,
 		size_t maxlen, gfp_t gfp_flags);
 /**
  * xdr_align_size - Calculate padded size of an object
  * @n: Size of an object being XDR encoded (in bytes)
  *
  * Return value:
  *   Size (in bytes) of the object including xdr padding
  */
 static inline size_t
 xdr_align_size(size_t n)
 {
 	const size_t mask = sizeof(__u32) - 1;

 	return (n + mask) & ~mask;
 }

 /**
  * xdr_stream_encode_u32 - Encode a 32-bit integer
  * @xdr: pointer to xdr_stream
  * @n: integer to encode
  *
  * Return values:
  *   On success, returns length in bytes of XDR buffer consumed
  *   %-EMSGSIZE on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
 {
 	const size_t len = sizeof(n);
 	__be32 *p = xdr_reserve_space(xdr, len);

 	if (unlikely(!p))
 		return -EMSGSIZE;
 	*p = cpu_to_be32(n);
 	return len;
 }

 /**
  * xdr_stream_encode_u64 - Encode a 64-bit integer
  * @xdr: pointer to xdr_stream
  * @n: 64-bit integer to encode
  *
  * Return values:
  *   On success, returns length in bytes of XDR buffer consumed
  *   %-EMSGSIZE on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
 {
 	const size_t len = sizeof(n);
 	__be32 *p = xdr_reserve_space(xdr, len);

 	if (unlikely(!p))
 		return -EMSGSIZE;
 	xdr_encode_hyper(p, n);
 	return len;
 }

 /**
  * xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
  * @xdr: pointer to xdr_stream
  * @ptr: pointer to opaque data object
  * @len: size of object pointed to by @ptr
  *
  * Return values:
  *   On success, returns length in bytes of XDR buffer consumed
  *   %-EMSGSIZE on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_encode_opaque_fixed(struct xdr_stream *xdr, const void *ptr, size_t len)
 {
 	__be32 *p = xdr_reserve_space(xdr, len);

 	if (unlikely(!p))
 		return -EMSGSIZE;
 	xdr_encode_opaque_fixed(p, ptr, len);
 	return xdr_align_size(len);
 }

 /**
  * xdr_stream_encode_opaque - Encode variable length opaque xdr data
  * @xdr: pointer to xdr_stream
  * @ptr: pointer to opaque data object
  * @len: size of object pointed to by @ptr
  *
  * Return values:
  *   On success, returns length in bytes of XDR buffer consumed
  *   %-EMSGSIZE on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_encode_opaque(struct xdr_stream *xdr, const void *ptr, size_t len)
 {
 	size_t count = sizeof(__u32) + xdr_align_size(len);
 	__be32 *p = xdr_reserve_space(xdr, count);

 	if (unlikely(!p))
 		return -EMSGSIZE;
 	xdr_encode_opaque(p, ptr, len);
 	return count;
 }

 /**
  * xdr_stream_decode_u32 - Decode a 32-bit integer
  * @xdr: pointer to xdr_stream
  * @ptr: location to store integer
  *
  * Return values:
  *   %0 on success
  *   %-EBADMSG on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_decode_u32(struct xdr_stream *xdr, __u32 *ptr)
 {
 	const size_t count = sizeof(*ptr);
 	__be32 *p = xdr_inline_decode(xdr, count);

 	if (unlikely(!p))
 		return -EBADMSG;
 	*ptr = be32_to_cpup(p);
 	return 0;
 }

 /**
  * xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
  * @xdr: pointer to xdr_stream
  * @ptr: location to store data
  * @len: size of buffer pointed to by @ptr
  *
  * Return values:
  *   On success, returns size of object stored in @ptr
  *   %-EBADMSG on XDR buffer overflow
  */
 static inline ssize_t
 xdr_stream_decode_opaque_fixed(struct xdr_stream *xdr, void *ptr, size_t len)
 {
 	__be32 *p = xdr_inline_decode(xdr, len);

 	if (unlikely(!p))
 		return -EBADMSG;
 	xdr_decode_opaque_fixed(p, ptr, len);
 	return len;
 }

 /**
  * xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
  * @xdr: pointer to xdr_stream
  * @ptr: location to store pointer to opaque data
  * @maxlen: maximum acceptable object size
  *
  * Note: the pointer stored in @ptr cannot be assumed valid after the XDR
  * buffer has been destroyed, or even after calling xdr_inline_decode()
  * on @xdr. It is therefore expected that the object it points to should
  * be processed immediately.
  *
  * Return values:
  *   On success, returns size of object stored in *@ptr
  *   %-EBADMSG on XDR buffer overflow
  *   %-EMSGSIZE if the size of the object would exceed @maxlen
  */
 static inline ssize_t
 xdr_stream_decode_opaque_inline(struct xdr_stream *xdr, void **ptr, size_t maxlen)
 {
 	__be32 *p;
 	__u32 len;

 	*ptr = NULL;
 	if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
 		return -EBADMSG;
 	if (len != 0) {
 		p = xdr_inline_decode(xdr, len);
 		if (unlikely(!p))
 			return -EBADMSG;
 		if (unlikely(len > maxlen))
 			return -EMSGSIZE;
 		*ptr = p;
 	}
 	return len;
 }
 #endif /* __KERNEL__ */

 #endif /* _SUNRPC_XDR_H_ */
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* XDR standard data types and function declarations
	*
	* Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
	*
	* Based on:
	* RFC 4506 "XDR: External Data Representation Standard", May 2006
	*/

	#ifndef _SUNRPC_XDR_H_
	#define _SUNRPC_XDR_H_

	#ifdef __KERNEL__

	#include <linux/uio.h>
	#include <asm/byteorder.h>
	#include <asm/unaligned.h>
	#include <linux/scatterlist.h>

	struct rpc_rqst;

	/*
	* Buffer adjustment
	*/
	#define XDR_QUADLEN(l) (((l) + 3) >> 2)

	/*
	* Generic opaque `network object.'
	*/
	#define XDR_MAX_NETOBJ 1024
	struct xdr_netobj {
	unsigned int len;
	u8 * data;
	};

	/*
	* Basic structure for transmission/reception of a client XDR message.
	* Features a header (for a linear buffer containing RPC headers
	* and the data payload for short messages), and then an array of
	* pages.
	* The tail iovec allows you to append data after the page array. Its
	* main interest is for appending padding to the pages in order to
	* satisfy the int_32-alignment requirements in RFC1832.
	*
	* For the future, we might want to string several of these together
	* in a list if anybody wants to make use of NFSv4 COMPOUND
	* operations and/or has a need for scatter/gather involving pages.
	*/
	struct xdr_buf {
	struct kvec head[1], /* RPC header + non-page data */
	tail[1]; /* Appended after page data */

	struct page ** pages; /* Array of pages */
	unsigned int page_base, /* Start of page data */
	page_len, /* Length of page data */
	flags; /* Flags for data disposition */
	#define XDRBUF_READ 0x01 /* target of file read */
	#define XDRBUF_WRITE 0x02 /* source of file write */

	unsigned int buflen, /* Total length of storage buffer */
	len; /* Length of XDR encoded message */
	};

	static inline void
	xdr_buf_init(struct xdr_buf buf, void start, size_t len)
	{
	buf->head[0].iov_base = start;
	buf->head[0].iov_len = len;
	buf->tail[0].iov_len = 0;
	buf->page_len = 0;
	buf->flags = 0;
	buf->len = 0;
	buf->buflen = len;
	}

	/*
	* pre-xdr'ed macros.
	*/

	#define xdr_zero cpu_to_be32(0)
	#define xdr_one cpu_to_be32(1)
	#define xdr_two cpu_to_be32(2)

	#define rpc_success cpu_to_be32(RPC_SUCCESS)
	#define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
	#define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
	#define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
	#define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
	#define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
	#define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)

	#define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
	#define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
	#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
	#define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
	#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
	#define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
	#define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
	#define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
	#define rpc_autherr_oldseqnum cpu_to_be32(101)

	/*
	* Miscellaneous XDR helper functions
	*/
	__be32 xdr_encode_opaque_fixed(__be32 p, const void *ptr, unsigned int len);
	__be32 xdr_encode_opaque(__be32 p, const void *ptr, unsigned int len);
	__be32 xdr_encode_string(__be32 p, const char *s);
	__be32 xdr_decode_string_inplace(__be32 p, char *sp, unsigned int lenp,
	unsigned int maxlen);
	__be32 xdr_encode_netobj(__be32 p, const struct xdr_netobj *);
	__be32 xdr_decode_netobj(__be32 p, struct xdr_netobj *);

	void xdr_inline_pages(struct xdr_buf *, unsigned int,
	struct page **, unsigned int, unsigned int);
	void xdr_terminate_string(struct xdr_buf *, const u32);

	static inline __be32 xdr_encode_array(__be32 p, const void *s, unsigned int len)
	{
	return xdr_encode_opaque(p, s, len);
	}

	/*
	* Decode 64bit quantities (NFSv3 support)
	*/
	static inline __be32 *
	xdr_encode_hyper(__be32 *p, __u64 val)
	{
	put_unaligned_be64(val, p);
	return p + 2;
	}

	static inline __be32 *
	xdr_decode_hyper(__be32 p, __u64 valp)
	{
	*valp = get_unaligned_be64(p);
	return p + 2;
	}

	static inline __be32 *
	xdr_decode_opaque_fixed(__be32 p, void ptr, unsigned int len)
	{
	memcpy(ptr, p, len);
	return p + XDR_QUADLEN(len);
	}

	/*
	* Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
	*/
	static inline int
	xdr_adjust_iovec(struct kvec iov, __be32 p)
	{
	return iov->iov_len = ((u8 ) p - (u8 ) iov->iov_base);
	}

	/*
	* XDR buffer helper functions
	*/
	extern void xdr_shift_buf(struct xdr_buf *, size_t);
	extern void xdr_buf_from_iov(struct kvec , struct xdr_buf );
	extern int xdr_buf_subsegment(struct xdr_buf , struct xdr_buf , unsigned int, unsigned int);
	extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
	extern int xdr_buf_read_netobj(struct xdr_buf , struct xdr_netobj , unsigned int);
	extern int read_bytes_from_xdr_buf(struct xdr_buf , unsigned int, void , unsigned int);
	extern int write_bytes_to_xdr_buf(struct xdr_buf , unsigned int, void , unsigned int);

	/*
	* Helper structure for copying from an sk_buff.
	*/
	struct xdr_skb_reader {
	struct sk_buff *skb;
	unsigned int offset;
	size_t count;
	__wsum csum;
	};

	typedef size_t (xdr_skb_read_actor)(struct xdr_skb_reader desc, void *to, size_t len);

	size_t xdr_skb_read_bits(struct xdr_skb_reader desc, void to, size_t len);
	extern int csum_partial_copy_to_xdr(struct xdr_buf , struct sk_buff );
	extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
	struct xdr_skb_reader *, xdr_skb_read_actor);

	extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
	extern int xdr_decode_word(struct xdr_buf , unsigned int, u32 );

	struct xdr_array2_desc;
	typedef int (xdr_xcode_elem_t)(struct xdr_array2_desc desc, void *elem);
	struct xdr_array2_desc {
	unsigned int elem_size;
	unsigned int array_len;
	unsigned int array_maxlen;
	xdr_xcode_elem_t xcode;
	};

	extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
	struct xdr_array2_desc *desc);
	extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
	struct xdr_array2_desc *desc);
	extern void _copy_from_pages(char p, struct page *pages, size_t pgbase,
	size_t len);

	/*
	* Provide some simple tools for XDR buffer overflow-checking etc.
	*/
	struct xdr_stream {
	__be32 p; / start of available buffer */
	struct xdr_buf buf; / XDR buffer to read/write */

	__be32 end; / end of available buffer space */
	struct kvec iov; / pointer to the current kvec */
	struct kvec scratch; /* Scratch buffer */
	struct page *page_ptr; / pointer to the current page */
	unsigned int nwords; /* Remaining decode buffer length */
	};

	/*
	* These are the xdr_stream style generic XDR encode and decode functions.
	*/
	typedef void (kxdreproc_t)(struct rpc_rqst rqstp, struct xdr_stream *xdr,
	const void *obj);
	typedef int (kxdrdproc_t)(struct rpc_rqst rqstp, struct xdr_stream *xdr,
	void *obj);

	extern void xdr_init_encode(struct xdr_stream xdr, struct xdr_buf buf, __be32 *p);
	extern __be32 xdr_reserve_space(struct xdr_stream xdr, size_t nbytes);
	extern void xdr_commit_encode(struct xdr_stream *xdr);
	extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
	extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
	extern void xdr_write_pages(struct xdr_stream xdr, struct page *pages,
	unsigned int base, unsigned int len);
	extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
	extern void xdr_init_decode(struct xdr_stream xdr, struct xdr_buf buf, __be32 *p);
	extern void xdr_init_decode_pages(struct xdr_stream xdr, struct xdr_buf buf,
	struct page **pages, unsigned int len);
	extern void xdr_set_scratch_buffer(struct xdr_stream xdr, void buf, size_t buflen);
	extern __be32 xdr_inline_decode(struct xdr_stream xdr, size_t nbytes);
	extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
	extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
	extern int xdr_process_buf(struct xdr_buf buf, unsigned int offset, unsigned int len, int (actor)(struct scatterlist , void ), void *data);

	/**
	* xdr_stream_remaining - Return the number of bytes remaining in the stream
	* @xdr: pointer to struct xdr_stream
	*
	* Return value:
	* Number of bytes remaining in @xdr before xdr->end
	*/
	static inline size_t
	xdr_stream_remaining(const struct xdr_stream *xdr)
	{
	return xdr->nwords << 2;
	}

	ssize_t xdr_stream_decode_string_dup(struct xdr_stream xdr, char *str,
	size_t maxlen, gfp_t gfp_flags);
	/**
	* xdr_align_size - Calculate padded size of an object
	* @n: Size of an object being XDR encoded (in bytes)
	*
	* Return value:
	* Size (in bytes) of the object including xdr padding
	*/
	static inline size_t
	xdr_align_size(size_t n)
	{
	const size_t mask = sizeof(__u32) - 1;

	return (n + mask) & ~mask;
	}

	/**
	* xdr_stream_encode_u32 - Encode a 32-bit integer
	* @xdr: pointer to xdr_stream
	* @n: integer to encode
	*
	* Return values:
	* On success, returns length in bytes of XDR buffer consumed
	* %-EMSGSIZE on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
	{
	const size_t len = sizeof(n);
	__be32 *p = xdr_reserve_space(xdr, len);

	if (unlikely(!p))
	return -EMSGSIZE;
	*p = cpu_to_be32(n);
	return len;
	}

	/**
	* xdr_stream_encode_u64 - Encode a 64-bit integer
	* @xdr: pointer to xdr_stream
	* @n: 64-bit integer to encode
	*
	* Return values:
	* On success, returns length in bytes of XDR buffer consumed
	* %-EMSGSIZE on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
	{
	const size_t len = sizeof(n);
	__be32 *p = xdr_reserve_space(xdr, len);

	if (unlikely(!p))
	return -EMSGSIZE;
	xdr_encode_hyper(p, n);
	return len;
	}

	/**
	* xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
	* @xdr: pointer to xdr_stream
	* @ptr: pointer to opaque data object
	* @len: size of object pointed to by @ptr
	*
	* Return values:
	* On success, returns length in bytes of XDR buffer consumed
	* %-EMSGSIZE on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_encode_opaque_fixed(struct xdr_stream xdr, const void ptr, size_t len)
	{
	__be32 *p = xdr_reserve_space(xdr, len);

	if (unlikely(!p))
	return -EMSGSIZE;
	xdr_encode_opaque_fixed(p, ptr, len);
	return xdr_align_size(len);
	}

	/**
	* xdr_stream_encode_opaque - Encode variable length opaque xdr data
	* @xdr: pointer to xdr_stream
	* @ptr: pointer to opaque data object
	* @len: size of object pointed to by @ptr
	*
	* Return values:
	* On success, returns length in bytes of XDR buffer consumed
	* %-EMSGSIZE on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_encode_opaque(struct xdr_stream xdr, const void ptr, size_t len)
	{
	size_t count = sizeof(__u32) + xdr_align_size(len);
	__be32 *p = xdr_reserve_space(xdr, count);

	if (unlikely(!p))
	return -EMSGSIZE;
	xdr_encode_opaque(p, ptr, len);
	return count;
	}

	/**
	* xdr_stream_decode_u32 - Decode a 32-bit integer
	* @xdr: pointer to xdr_stream
	* @ptr: location to store integer
	*
	* Return values:
	* %0 on success
	* %-EBADMSG on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_decode_u32(struct xdr_stream xdr, __u32 ptr)
	{
	const size_t count = sizeof(*ptr);
	__be32 *p = xdr_inline_decode(xdr, count);

	if (unlikely(!p))
	return -EBADMSG;
	*ptr = be32_to_cpup(p);
	return 0;
	}

	/**
	* xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
	* @xdr: pointer to xdr_stream
	* @ptr: location to store data
	* @len: size of buffer pointed to by @ptr
	*
	* Return values:
	* On success, returns size of object stored in @ptr
	* %-EBADMSG on XDR buffer overflow
	*/
	static inline ssize_t
	xdr_stream_decode_opaque_fixed(struct xdr_stream xdr, void ptr, size_t len)
	{
	__be32 *p = xdr_inline_decode(xdr, len);

	if (unlikely(!p))
	return -EBADMSG;
	xdr_decode_opaque_fixed(p, ptr, len);
	return len;
	}

	/**
	* xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
	* @xdr: pointer to xdr_stream
	* @ptr: location to store pointer to opaque data
	* @maxlen: maximum acceptable object size
	*
	* Note: the pointer stored in @ptr cannot be assumed valid after the XDR
	* buffer has been destroyed, or even after calling xdr_inline_decode()
	* on @xdr. It is therefore expected that the object it points to should
	* be processed immediately.
	*
	* Return values:
	* On success, returns size of object stored in *@ptr
	* %-EBADMSG on XDR buffer overflow
	* %-EMSGSIZE if the size of the object would exceed @maxlen
	*/
	static inline ssize_t
	xdr_stream_decode_opaque_inline(struct xdr_stream xdr, void *ptr, size_t maxlen)
	{
	__be32 *p;
	__u32 len;

	*ptr = NULL;
	if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
	return -EBADMSG;
	if (len != 0) {
	p = xdr_inline_decode(xdr, len);
	if (unlikely(!p))
	return -EBADMSG;
	if (unlikely(len > maxlen))
	return -EMSGSIZE;
	*ptr = p;
	}
	return len;
	}
	#endif /* __KERNEL__ */

	#endif /* _SUNRPC_XDR_H_ */