[GitHub/moto-9609/android_kernel_motorola_exynos9610.git] / include / linux / 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.' At the kernel level, this type
 * is used only by lockd.
 */
#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_ */
Commit	Line	Data
	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	/*
	3	* XDR standard data types and function declarations
	4	*
	5	* Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
	6	*
	7	* Based on:
	8	* RFC 4506 "XDR: External Data Representation Standard", May 2006
	9	*/
	10
	11	#ifndef _SUNRPC_XDR_H_
	12	#define _SUNRPC_XDR_H_
	13
	14	#ifdef __KERNEL__
	15
	16	#include <linux/uio.h>
	17	#include <asm/byteorder.h>
	18	#include <asm/unaligned.h>
	19	#include <linux/scatterlist.h>
	20
	21	struct rpc_rqst;
	22
	23	/*
	24	* Buffer adjustment
	25	*/
	26	#define XDR_QUADLEN(l) (((l) + 3) >> 2)
	27
	28	/*
	29	* Generic opaque `network object.' At the kernel level, this type
	30	* is used only by lockd.
	31	*/
	32	#define XDR_MAX_NETOBJ 1024
	33	struct xdr_netobj {
	34	unsigned int len;
	35	u8 * data;
	36	};
	37
	38	/*
	39	* Basic structure for transmission/reception of a client XDR message.
	40	* Features a header (for a linear buffer containing RPC headers
	41	* and the data payload for short messages), and then an array of
	42	* pages.
	43	* The tail iovec allows you to append data after the page array. Its
	44	* main interest is for appending padding to the pages in order to
	45	* satisfy the int_32-alignment requirements in RFC1832.
	46	*
	47	* For the future, we might want to string several of these together
	48	* in a list if anybody wants to make use of NFSv4 COMPOUND
	49	* operations and/or has a need for scatter/gather involving pages.
	50	*/
	51	struct xdr_buf {
	52	struct kvec head[1], /* RPC header + non-page data */
	53	tail[1]; /* Appended after page data */
	54
	55	struct page ** pages; /* Array of pages */
	56	unsigned int page_base, /* Start of page data */
	57	page_len, /* Length of page data */
	58	flags; /* Flags for data disposition */
	59	#define XDRBUF_READ 0x01 /* target of file read */
	60	#define XDRBUF_WRITE 0x02 /* source of file write */
	61
	62	unsigned int buflen, /* Total length of storage buffer */
	63	len; /* Length of XDR encoded message */
	64	};
	65
	66	static inline void
	67	xdr_buf_init(struct xdr_buf buf, void start, size_t len)
	68	{
	69	buf->head[0].iov_base = start;
	70	buf->head[0].iov_len = len;
	71	buf->tail[0].iov_len = 0;
	72	buf->page_len = 0;
	73	buf->flags = 0;
	74	buf->len = 0;
	75	buf->buflen = len;
	76	}
	77
	78	/*
	79	* pre-xdr'ed macros.
	80	*/
	81
	82	#define xdr_zero cpu_to_be32(0)
	83	#define xdr_one cpu_to_be32(1)
	84	#define xdr_two cpu_to_be32(2)
	85
	86	#define rpc_success cpu_to_be32(RPC_SUCCESS)
	87	#define rpc_prog_unavail cpu_to_be32(RPC_PROG_UNAVAIL)
	88	#define rpc_prog_mismatch cpu_to_be32(RPC_PROG_MISMATCH)
	89	#define rpc_proc_unavail cpu_to_be32(RPC_PROC_UNAVAIL)
	90	#define rpc_garbage_args cpu_to_be32(RPC_GARBAGE_ARGS)
	91	#define rpc_system_err cpu_to_be32(RPC_SYSTEM_ERR)
	92	#define rpc_drop_reply cpu_to_be32(RPC_DROP_REPLY)
	93
	94	#define rpc_auth_ok cpu_to_be32(RPC_AUTH_OK)
	95	#define rpc_autherr_badcred cpu_to_be32(RPC_AUTH_BADCRED)
	96	#define rpc_autherr_rejectedcred cpu_to_be32(RPC_AUTH_REJECTEDCRED)
	97	#define rpc_autherr_badverf cpu_to_be32(RPC_AUTH_BADVERF)
	98	#define rpc_autherr_rejectedverf cpu_to_be32(RPC_AUTH_REJECTEDVERF)
	99	#define rpc_autherr_tooweak cpu_to_be32(RPC_AUTH_TOOWEAK)
	100	#define rpcsec_gsserr_credproblem cpu_to_be32(RPCSEC_GSS_CREDPROBLEM)
	101	#define rpcsec_gsserr_ctxproblem cpu_to_be32(RPCSEC_GSS_CTXPROBLEM)
	102	#define rpc_autherr_oldseqnum cpu_to_be32(101)
	103
	104	/*
	105	* Miscellaneous XDR helper functions
	106	*/
	107	__be32 xdr_encode_opaque_fixed(__be32 p, const void *ptr, unsigned int len);
	108	__be32 xdr_encode_opaque(__be32 p, const void *ptr, unsigned int len);
	109	__be32 xdr_encode_string(__be32 p, const char *s);
	110	__be32 xdr_decode_string_inplace(__be32 p, char *sp, unsigned int lenp,
	111	unsigned int maxlen);
	112	__be32 xdr_encode_netobj(__be32 p, const struct xdr_netobj *);
	113	__be32 xdr_decode_netobj(__be32 p, struct xdr_netobj *);
	114
	115	void xdr_inline_pages(struct xdr_buf *, unsigned int,
	116	struct page **, unsigned int, unsigned int);
	117	void xdr_terminate_string(struct xdr_buf *, const u32);
	118
	119	static inline __be32 xdr_encode_array(__be32 p, const void *s, unsigned int len)
	120	{
	121	return xdr_encode_opaque(p, s, len);
	122	}
	123
	124	/*
	125	* Decode 64bit quantities (NFSv3 support)
	126	*/
	127	static inline __be32 *
	128	xdr_encode_hyper(__be32 *p, __u64 val)
	129	{
	130	put_unaligned_be64(val, p);
	131	return p + 2;
	132	}
	133
	134	static inline __be32 *
	135	xdr_decode_hyper(__be32 p, __u64 valp)
	136	{
	137	*valp = get_unaligned_be64(p);
	138	return p + 2;
	139	}
	140
	141	static inline __be32 *
	142	xdr_decode_opaque_fixed(__be32 p, void ptr, unsigned int len)
	143	{
	144	memcpy(ptr, p, len);
	145	return p + XDR_QUADLEN(len);
	146	}
	147
	148	/*
	149	* Adjust kvec to reflect end of xdr'ed data (RPC client XDR)
	150	*/
	151	static inline int
	152	xdr_adjust_iovec(struct kvec iov, __be32 p)
	153	{
	154	return iov->iov_len = ((u8 ) p - (u8 ) iov->iov_base);
	155	}
	156
	157	/*
	158	* XDR buffer helper functions
	159	*/
	160	extern void xdr_shift_buf(struct xdr_buf *, size_t);
	161	extern void xdr_buf_from_iov(struct kvec , struct xdr_buf );
	162	extern int xdr_buf_subsegment(struct xdr_buf , struct xdr_buf , unsigned int, unsigned int);
	163	extern void xdr_buf_trim(struct xdr_buf *, unsigned int);
	164	extern int xdr_buf_read_netobj(struct xdr_buf , struct xdr_netobj , unsigned int);
	165	extern int read_bytes_from_xdr_buf(struct xdr_buf , unsigned int, void , unsigned int);
	166	extern int write_bytes_to_xdr_buf(struct xdr_buf , unsigned int, void , unsigned int);
	167
	168	/*
	169	* Helper structure for copying from an sk_buff.
	170	*/
	171	struct xdr_skb_reader {
	172	struct sk_buff *skb;
	173	unsigned int offset;
	174	size_t count;
	175	__wsum csum;
	176	};
	177
	178	typedef size_t (xdr_skb_read_actor)(struct xdr_skb_reader desc, void *to, size_t len);
	179
	180	size_t xdr_skb_read_bits(struct xdr_skb_reader desc, void to, size_t len);
	181	extern int csum_partial_copy_to_xdr(struct xdr_buf , struct sk_buff );
	182	extern ssize_t xdr_partial_copy_from_skb(struct xdr_buf *, unsigned int,
	183	struct xdr_skb_reader *, xdr_skb_read_actor);
	184
	185	extern int xdr_encode_word(struct xdr_buf *, unsigned int, u32);
	186	extern int xdr_decode_word(struct xdr_buf , unsigned int, u32 );
	187
	188	struct xdr_array2_desc;
	189	typedef int (xdr_xcode_elem_t)(struct xdr_array2_desc desc, void *elem);
	190	struct xdr_array2_desc {
	191	unsigned int elem_size;
	192	unsigned int array_len;
	193	unsigned int array_maxlen;
	194	xdr_xcode_elem_t xcode;
	195	};
	196
	197	extern int xdr_decode_array2(struct xdr_buf *buf, unsigned int base,
	198	struct xdr_array2_desc *desc);
	199	extern int xdr_encode_array2(struct xdr_buf *buf, unsigned int base,
	200	struct xdr_array2_desc *desc);
	201	extern void _copy_from_pages(char p, struct page *pages, size_t pgbase,
	202	size_t len);
	203
	204	/*
	205	* Provide some simple tools for XDR buffer overflow-checking etc.
	206	*/
	207	struct xdr_stream {
	208	__be32 p; / start of available buffer */
	209	struct xdr_buf buf; / XDR buffer to read/write */
	210
	211	__be32 end; / end of available buffer space */
	212	struct kvec iov; / pointer to the current kvec */
	213	struct kvec scratch; /* Scratch buffer */
	214	struct page *page_ptr; / pointer to the current page */
	215	unsigned int nwords; /* Remaining decode buffer length */
	216	};
	217
	218	/*
	219	* These are the xdr_stream style generic XDR encode and decode functions.
	220	*/
	221	typedef void (kxdreproc_t)(struct rpc_rqst rqstp, struct xdr_stream *xdr,
	222	const void *obj);
	223	typedef int (kxdrdproc_t)(struct rpc_rqst rqstp, struct xdr_stream *xdr,
	224	void *obj);
	225
	226	extern void xdr_init_encode(struct xdr_stream xdr, struct xdr_buf buf, __be32 *p);
	227	extern __be32 xdr_reserve_space(struct xdr_stream xdr, size_t nbytes);
	228	extern void xdr_commit_encode(struct xdr_stream *xdr);
	229	extern void xdr_truncate_encode(struct xdr_stream *xdr, size_t len);
	230	extern int xdr_restrict_buflen(struct xdr_stream *xdr, int newbuflen);
	231	extern void xdr_write_pages(struct xdr_stream xdr, struct page *pages,
	232	unsigned int base, unsigned int len);
	233	extern unsigned int xdr_stream_pos(const struct xdr_stream *xdr);
	234	extern void xdr_init_decode(struct xdr_stream xdr, struct xdr_buf buf, __be32 *p);
	235	extern void xdr_init_decode_pages(struct xdr_stream xdr, struct xdr_buf buf,
	236	struct page **pages, unsigned int len);
	237	extern void xdr_set_scratch_buffer(struct xdr_stream xdr, void buf, size_t buflen);
	238	extern __be32 xdr_inline_decode(struct xdr_stream xdr, size_t nbytes);
	239	extern unsigned int xdr_read_pages(struct xdr_stream *xdr, unsigned int len);
	240	extern void xdr_enter_page(struct xdr_stream *xdr, unsigned int len);
	241	extern int xdr_process_buf(struct xdr_buf buf, unsigned int offset, unsigned int len, int (actor)(struct scatterlist , void ), void *data);
	242
	243	/**
	244	* xdr_stream_remaining - Return the number of bytes remaining in the stream
	245	* @xdr: pointer to struct xdr_stream
	246	*
	247	* Return value:
	248	* Number of bytes remaining in @xdr before xdr->end
	249	*/
	250	static inline size_t
	251	xdr_stream_remaining(const struct xdr_stream *xdr)
	252	{
	253	return xdr->nwords << 2;
	254	}
	255
	256	ssize_t xdr_stream_decode_string_dup(struct xdr_stream xdr, char *str,
	257	size_t maxlen, gfp_t gfp_flags);
	258	/**
	259	* xdr_align_size - Calculate padded size of an object
	260	* @n: Size of an object being XDR encoded (in bytes)
	261	*
	262	* Return value:
	263	* Size (in bytes) of the object including xdr padding
	264	*/
	265	static inline size_t
	266	xdr_align_size(size_t n)
	267	{
	268	const size_t mask = sizeof(__u32) - 1;
	269
	270	return (n + mask) & ~mask;
	271	}
	272
	273	/**
	274	* xdr_stream_encode_u32 - Encode a 32-bit integer
	275	* @xdr: pointer to xdr_stream
	276	* @n: integer to encode
	277	*
	278	* Return values:
	279	* On success, returns length in bytes of XDR buffer consumed
	280	* %-EMSGSIZE on XDR buffer overflow
	281	*/
	282	static inline ssize_t
	283	xdr_stream_encode_u32(struct xdr_stream *xdr, __u32 n)
	284	{
	285	const size_t len = sizeof(n);
	286	__be32 *p = xdr_reserve_space(xdr, len);
	287
	288	if (unlikely(!p))
	289	return -EMSGSIZE;
	290	*p = cpu_to_be32(n);
	291	return len;
	292	}
	293
	294	/**
	295	* xdr_stream_encode_u64 - Encode a 64-bit integer
	296	* @xdr: pointer to xdr_stream
	297	* @n: 64-bit integer to encode
	298	*
	299	* Return values:
	300	* On success, returns length in bytes of XDR buffer consumed
	301	* %-EMSGSIZE on XDR buffer overflow
	302	*/
	303	static inline ssize_t
	304	xdr_stream_encode_u64(struct xdr_stream *xdr, __u64 n)
	305	{
	306	const size_t len = sizeof(n);
	307	__be32 *p = xdr_reserve_space(xdr, len);
	308
	309	if (unlikely(!p))
	310	return -EMSGSIZE;
	311	xdr_encode_hyper(p, n);
	312	return len;
	313	}
	314
	315	/**
	316	* xdr_stream_encode_opaque_fixed - Encode fixed length opaque xdr data
	317	* @xdr: pointer to xdr_stream
	318	* @ptr: pointer to opaque data object
	319	* @len: size of object pointed to by @ptr
	320	*
	321	* Return values:
	322	* On success, returns length in bytes of XDR buffer consumed
	323	* %-EMSGSIZE on XDR buffer overflow
	324	*/
	325	static inline ssize_t
	326	xdr_stream_encode_opaque_fixed(struct xdr_stream xdr, const void ptr, size_t len)
	327	{
	328	__be32 *p = xdr_reserve_space(xdr, len);
	329
	330	if (unlikely(!p))
	331	return -EMSGSIZE;
	332	xdr_encode_opaque_fixed(p, ptr, len);
	333	return xdr_align_size(len);
	334	}
	335
	336	/**
	337	* xdr_stream_encode_opaque - Encode variable length opaque xdr data
	338	* @xdr: pointer to xdr_stream
	339	* @ptr: pointer to opaque data object
	340	* @len: size of object pointed to by @ptr
	341	*
	342	* Return values:
	343	* On success, returns length in bytes of XDR buffer consumed
	344	* %-EMSGSIZE on XDR buffer overflow
	345	*/
	346	static inline ssize_t
	347	xdr_stream_encode_opaque(struct xdr_stream xdr, const void ptr, size_t len)
	348	{
	349	size_t count = sizeof(__u32) + xdr_align_size(len);
	350	__be32 *p = xdr_reserve_space(xdr, count);
	351
	352	if (unlikely(!p))
	353	return -EMSGSIZE;
	354	xdr_encode_opaque(p, ptr, len);
	355	return count;
	356	}
	357
	358	/**
	359	* xdr_stream_decode_u32 - Decode a 32-bit integer
	360	* @xdr: pointer to xdr_stream
	361	* @ptr: location to store integer
	362	*
	363	* Return values:
	364	* %0 on success
	365	* %-EBADMSG on XDR buffer overflow
	366	*/
	367	static inline ssize_t
	368	xdr_stream_decode_u32(struct xdr_stream xdr, __u32 ptr)
	369	{
	370	const size_t count = sizeof(*ptr);
	371	__be32 *p = xdr_inline_decode(xdr, count);
	372
	373	if (unlikely(!p))
	374	return -EBADMSG;
	375	*ptr = be32_to_cpup(p);
	376	return 0;
	377	}
	378
	379	/**
	380	* xdr_stream_decode_opaque_fixed - Decode fixed length opaque xdr data
	381	* @xdr: pointer to xdr_stream
	382	* @ptr: location to store data
	383	* @len: size of buffer pointed to by @ptr
	384	*
	385	* Return values:
	386	* On success, returns size of object stored in @ptr
	387	* %-EBADMSG on XDR buffer overflow
	388	*/
	389	static inline ssize_t
	390	xdr_stream_decode_opaque_fixed(struct xdr_stream xdr, void ptr, size_t len)
	391	{
	392	__be32 *p = xdr_inline_decode(xdr, len);
	393
	394	if (unlikely(!p))
	395	return -EBADMSG;
	396	xdr_decode_opaque_fixed(p, ptr, len);
	397	return len;
	398	}
	399
	400	/**
	401	* xdr_stream_decode_opaque_inline - Decode variable length opaque xdr data
	402	* @xdr: pointer to xdr_stream
	403	* @ptr: location to store pointer to opaque data
	404	* @maxlen: maximum acceptable object size
	405	*
	406	* Note: the pointer stored in @ptr cannot be assumed valid after the XDR
	407	* buffer has been destroyed, or even after calling xdr_inline_decode()
	408	* on @xdr. It is therefore expected that the object it points to should
	409	* be processed immediately.
	410	*
	411	* Return values:
	412	* On success, returns size of object stored in *@ptr
	413	* %-EBADMSG on XDR buffer overflow
	414	* %-EMSGSIZE if the size of the object would exceed @maxlen
	415	*/
	416	static inline ssize_t
	417	xdr_stream_decode_opaque_inline(struct xdr_stream xdr, void *ptr, size_t maxlen)
	418	{
	419	__be32 *p;
	420	__u32 len;
	421
	422	*ptr = NULL;
	423	if (unlikely(xdr_stream_decode_u32(xdr, &len) < 0))
	424	return -EBADMSG;
	425	if (len != 0) {
	426	p = xdr_inline_decode(xdr, len);
	427	if (unlikely(!p))
	428	return -EBADMSG;
	429	if (unlikely(len > maxlen))
	430	return -EMSGSIZE;
	431	*ptr = p;
	432	}
	433	return len;
	434	}
	435	#endif /* __KERNEL__ */
	436
	437	#endif /* _SUNRPC_XDR_H_ */