/*
   * linux/fs/nfs/nfs3xdr.c
   *
   * XDR functions to encode/decode NFSv3 RPC arguments and results.
   *
   * Copyright (C) 1996, 1997 Olaf Kirch
   */
  
  #include <linux/param.h>
  #include <linux/time.h>
  #include <linux/mm.h>
  #include <linux/errno.h>
  #include <linux/string.h>
  #include <linux/in.h>
  #include <linux/pagemap.h>
  #include <linux/proc_fs.h>
  #include <linux/kdev_t.h>
  #include <linux/sunrpc/clnt.h>
  #include <linux/nfs.h>
  #include <linux/nfs3.h>
  #include <linux/nfs_fs.h>
  #include <linux/nfsacl.h>
  #include "internal.h"
  
  #define NFSDBG_FACILITY		NFSDBG_XDR
  
  /* Mapping from NFS error code to "errno" error code. */
  #define errno_NFSERR_IO		EIO
  
  /*
   * Declare the space requirements for NFS arguments and replies as
   * number of 32bit-words
   */
  #define NFS3_fhandle_sz		(1+16)
  #define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
  #define NFS3_sattr_sz		(15)
  #define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
  #define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
  #define NFS3_fattr_sz		(21)
  #define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
  #define NFS3_wcc_attr_sz	(6)
  #define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
  #define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
  #define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
  #define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
  
  #define NFS3_getattrargs_sz	(NFS3_fh_sz)
  #define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
  #define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
  #define NFS3_accessargs_sz	(NFS3_fh_sz+1)
  #define NFS3_readlinkargs_sz	(NFS3_fh_sz)
  #define NFS3_readargs_sz	(NFS3_fh_sz+3)
  #define NFS3_writeargs_sz	(NFS3_fh_sz+5)
  #define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
  #define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
  #define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
  #define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
  #define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
  #define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
  #define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
  #define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
  #define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
  #define NFS3_commitargs_sz	(NFS3_fh_sz+3)
  
  #define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
  #define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
  #define NFS3_removeres_sz	(NFS3_setattrres_sz)
  #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
  #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
  #define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1)
  #define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3)
  #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
  #define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
  #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
  #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
  #define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2)
  #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
  #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
  #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
  #define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)
  
  #define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
  #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
  				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
  #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
  				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
  #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
  
  static int nfs3_stat_to_errno(enum nfs_stat);
  
  /*
   * Map file type to S_IFMT bits
   */
  static const umode_t nfs_type2fmt[] = {
  	[NF3BAD] = 0,
  	[NF3REG] = S_IFREG,
  	[NF3DIR] = S_IFDIR,
  	[NF3BLK] = S_IFBLK,
  	[NF3CHR] = S_IFCHR,
  	[NF3LNK] = S_IFLNK,
  	[NF3SOCK] = S_IFSOCK,
  	[NF3FIFO] = S_IFIFO,
  };
  
  /*
   * While encoding arguments, set up the reply buffer in advance to
   * receive reply data directly into the page cache.
   */
  static void prepare_reply_buffer(struct rpc_rqst *req, struct page **pages,
  				 unsigned int base, unsigned int len,
  				 unsigned int bufsize)
  {
  	struct rpc_auth	*auth = req->rq_cred->cr_auth;
  	unsigned int replen;
  
  	replen = RPC_REPHDRSIZE + auth->au_rslack + bufsize;
  	xdr_inline_pages(&req->rq_rcv_buf, replen << 2, pages, base, len);
  }
  
  /*
   * Handle decode buffer overflows out-of-line.
   */
  static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
  {
  	dprintk("NFS: %s prematurely hit the end of our receive buffer. "
  		"Remaining buffer length is %tu words.
  ",
  		func, xdr->end - xdr->p);
  }
  
  
  /*
   * Encode/decode NFSv3 basic data types
   *
   * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
   * "NFS Version 3 Protocol Specification".
   *
   * Not all basic data types have their own encoding and decoding
   * functions.  For run-time efficiency, some data types are encoded
   * or decoded inline.
   */
  
  static void encode_uint32(struct xdr_stream *xdr, u32 value)
  {
  	__be32 *p = xdr_reserve_space(xdr, 4);
  	*p = cpu_to_be32(value);
  }
  
  static int decode_uint32(struct xdr_stream *xdr, u32 *value)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	*value = be32_to_cpup(p);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int decode_uint64(struct xdr_stream *xdr, u64 *value)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 8);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	xdr_decode_hyper(p, value);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * fileid3
   *
   *	typedef uint64 fileid3;
   */
  static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
  {
  	return xdr_decode_hyper(p, fileid);
  }
  
  static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
  {
  	return decode_uint64(xdr, fileid);
  }
  
  /*
   * filename3
   *
   *	typedef string filename3<>;
   */
  static void encode_filename3(struct xdr_stream *xdr,
  			     const char *name, u32 length)
  {
  	__be32 *p;
  
  	WARN_ON_ONCE(length > NFS3_MAXNAMLEN);
  	p = xdr_reserve_space(xdr, 4 + length);
  	xdr_encode_opaque(p, name, length);
  }
  
  static int decode_inline_filename3(struct xdr_stream *xdr,
  				   const char **name, u32 *length)
  {
  	__be32 *p;
  	u32 count;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	count = be32_to_cpup(p);
  	if (count > NFS3_MAXNAMLEN)
  		goto out_nametoolong;
  	p = xdr_inline_decode(xdr, count);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	*name = (const char *)p;
  	*length = count;
  	return 0;
  
  out_nametoolong:
  	dprintk("NFS: returned filename too long: %u
  ", count);
  	return -ENAMETOOLONG;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * nfspath3
   *
   *	typedef string nfspath3<>;
   */
  static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
  			    const u32 length)
  {
  	encode_uint32(xdr, length);
  	xdr_write_pages(xdr, pages, 0, length);
  }
  
  static int decode_nfspath3(struct xdr_stream *xdr)
  {
  	u32 recvd, count;
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	count = be32_to_cpup(p);
  	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
  		goto out_nametoolong;
  	recvd = xdr_read_pages(xdr, count);
  	if (unlikely(count > recvd))
  		goto out_cheating;
  	xdr_terminate_string(xdr->buf, count);
  	return 0;
  
  out_nametoolong:
  	dprintk("NFS: returned pathname too long: %u
  ", count);
  	return -ENAMETOOLONG;
  out_cheating:
  	dprintk("NFS: server cheating in pathname result: "
  		"count %u > recvd %u
  ", count, recvd);
  	return -EIO;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * cookie3
   *
   *	typedef uint64 cookie3
   */
  static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
  {
  	return xdr_encode_hyper(p, cookie);
  }
  
  static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
  {
  	return decode_uint64(xdr, cookie);
  }
  
  /*
   * cookieverf3
   *
   *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
   */
  static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
  {
  	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
  	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
  }
  
  static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * createverf3
   *
   *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
   */
  static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
  {
  	__be32 *p;
  
  	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
  	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
  }
  
  static int decode_writeverf3(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	memcpy(verifier->data, p, NFS3_WRITEVERFSIZE);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * size3
   *
   *	typedef uint64 size3;
   */
  static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
  {
  	return xdr_decode_hyper(p, size);
  }
  
  /*
   * nfsstat3
   *
   *	enum nfsstat3 {
   *		NFS3_OK = 0,
   *		...
   *	}
   */
  #define NFS3_OK		NFS_OK
  
  static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	*status = be32_to_cpup(p);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * ftype3
   *
   *	enum ftype3 {
   *		NF3REG	= 1,
   *		NF3DIR	= 2,
   *		NF3BLK	= 3,
   *		NF3CHR	= 4,
   *		NF3LNK	= 5,
   *		NF3SOCK	= 6,
   *		NF3FIFO	= 7
   *	};
   */
  static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
  {
  	encode_uint32(xdr, type);
  }
  
  static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
  {
  	u32 type;
  
  	type = be32_to_cpup(p++);
  	if (type > NF3FIFO)
  		type = NF3NON;
  	*mode = nfs_type2fmt[type];
  	return p;
  }
  
  /*
   * specdata3
   *
   *     struct specdata3 {
   *             uint32  specdata1;
   *             uint32  specdata2;
   *     };
   */
  static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
  {
  	__be32 *p;
  
  	p = xdr_reserve_space(xdr, 8);
  	*p++ = cpu_to_be32(MAJOR(rdev));
  	*p = cpu_to_be32(MINOR(rdev));
  }
  
  static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
  {
  	unsigned int major, minor;
  
  	major = be32_to_cpup(p++);
  	minor = be32_to_cpup(p++);
  	*rdev = MKDEV(major, minor);
  	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
  		*rdev = 0;
  	return p;
  }
  
  /*
   * nfs_fh3
   *
   *	struct nfs_fh3 {
   *		opaque       data<NFS3_FHSIZE>;
   *	};
   */
  static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
  {
  	__be32 *p;
  
  	WARN_ON_ONCE(fh->size > NFS3_FHSIZE);
  	p = xdr_reserve_space(xdr, 4 + fh->size);
  	xdr_encode_opaque(p, fh->data, fh->size);
  }
  
  static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
  {
  	u32 length;
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	length = be32_to_cpup(p++);
  	if (unlikely(length > NFS3_FHSIZE))
  		goto out_toobig;
  	p = xdr_inline_decode(xdr, length);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	fh->size = length;
  	memcpy(fh->data, p, length);
  	return 0;
  out_toobig:
  	dprintk("NFS: file handle size (%u) too big
  ", length);
  	return -E2BIG;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static void zero_nfs_fh3(struct nfs_fh *fh)
  {
  	memset(fh, 0, sizeof(*fh));
  }
  
  /*
   * nfstime3
   *
   *	struct nfstime3 {
   *		uint32	seconds;
   *		uint32	nseconds;
   *	};
   */
  static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec *timep)
  {
  	*p++ = cpu_to_be32(timep->tv_sec);
  	*p++ = cpu_to_be32(timep->tv_nsec);
  	return p;
  }
  
  static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec *timep)
  {
  	timep->tv_sec = be32_to_cpup(p++);
  	timep->tv_nsec = be32_to_cpup(p++);
  	return p;
  }
  
  /*
   * sattr3
   *
   *	enum time_how {
   *		DONT_CHANGE		= 0,
   *		SET_TO_SERVER_TIME	= 1,
   *		SET_TO_CLIENT_TIME	= 2
   *	};
   *
   *	union set_mode3 switch (bool set_it) {
   *	case TRUE:
   *		mode3	mode;
   *	default:
   *		void;
   *	};
   *
   *	union set_uid3 switch (bool set_it) {
   *	case TRUE:
   *		uid3	uid;
   *	default:
   *		void;
   *	};
   *
   *	union set_gid3 switch (bool set_it) {
   *	case TRUE:
   *		gid3	gid;
   *	default:
   *		void;
   *	};
   *
   *	union set_size3 switch (bool set_it) {
   *	case TRUE:
   *		size3	size;
   *	default:
   *		void;
   *	};
   *
   *	union set_atime switch (time_how set_it) {
   *	case SET_TO_CLIENT_TIME:
   *		nfstime3	atime;
   *	default:
   *		void;
   *	};
   *
   *	union set_mtime switch (time_how set_it) {
   *	case SET_TO_CLIENT_TIME:
   *		nfstime3  mtime;
   *	default:
   *		void;
   *	};
   *
   *	struct sattr3 {
   *		set_mode3	mode;
   *		set_uid3	uid;
   *		set_gid3	gid;
   *		set_size3	size;
   *		set_atime	atime;
   *		set_mtime	mtime;
   *	};
   */
  static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr)
  {
  	u32 nbytes;
  	__be32 *p;
  
  	/*
  	 * In order to make only a single xdr_reserve_space() call,
  	 * pre-compute the total number of bytes to be reserved.
  	 * Six boolean values, one for each set_foo field, are always
  	 * present in the encoded result, so start there.
  	 */
  	nbytes = 6 * 4;
  	if (attr->ia_valid & ATTR_MODE)
  		nbytes += 4;
  	if (attr->ia_valid & ATTR_UID)
  		nbytes += 4;
  	if (attr->ia_valid & ATTR_GID)
  		nbytes += 4;
  	if (attr->ia_valid & ATTR_SIZE)
  		nbytes += 8;
  	if (attr->ia_valid & ATTR_ATIME_SET)
  		nbytes += 8;
  	if (attr->ia_valid & ATTR_MTIME_SET)
  		nbytes += 8;
  	p = xdr_reserve_space(xdr, nbytes);
  
  	if (attr->ia_valid & ATTR_MODE) {
  		*p++ = xdr_one;
  		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
  	} else
  		*p++ = xdr_zero;
  
  	if (attr->ia_valid & ATTR_UID) {
  		*p++ = xdr_one;
  		*p++ = cpu_to_be32(from_kuid(&init_user_ns, attr->ia_uid));
  	} else
  		*p++ = xdr_zero;
  
  	if (attr->ia_valid & ATTR_GID) {
  		*p++ = xdr_one;
  		*p++ = cpu_to_be32(from_kgid(&init_user_ns, attr->ia_gid));
  	} else
  		*p++ = xdr_zero;
  
  	if (attr->ia_valid & ATTR_SIZE) {
  		*p++ = xdr_one;
  		p = xdr_encode_hyper(p, (u64)attr->ia_size);
  	} else
  		*p++ = xdr_zero;
  
  	if (attr->ia_valid & ATTR_ATIME_SET) {
  		*p++ = xdr_two;
  		p = xdr_encode_nfstime3(p, &attr->ia_atime);
  	} else if (attr->ia_valid & ATTR_ATIME) {
  		*p++ = xdr_one;
  	} else
  		*p++ = xdr_zero;
  
  	if (attr->ia_valid & ATTR_MTIME_SET) {
  		*p++ = xdr_two;
  		xdr_encode_nfstime3(p, &attr->ia_mtime);
  	} else if (attr->ia_valid & ATTR_MTIME) {
  		*p = xdr_one;
  	} else
  		*p = xdr_zero;
  }
  
  /*
   * fattr3
   *
   *	struct fattr3 {
   *		ftype3		type;
   *		mode3		mode;
   *		uint32		nlink;
   *		uid3		uid;
   *		gid3		gid;
   *		size3		size;
   *		size3		used;
   *		specdata3	rdev;
   *		uint64		fsid;
   *		fileid3		fileid;
   *		nfstime3	atime;
   *		nfstime3	mtime;
   *		nfstime3	ctime;
   *	};
   */
  static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr)
  {
  	umode_t fmode;
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  
  	p = xdr_decode_ftype3(p, &fmode);
  
  	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
  	fattr->nlink = be32_to_cpup(p++);
  	fattr->uid = make_kuid(&init_user_ns, be32_to_cpup(p++));
  	if (!uid_valid(fattr->uid))
  		goto out_uid;
  	fattr->gid = make_kgid(&init_user_ns, be32_to_cpup(p++));
  	if (!gid_valid(fattr->gid))
  		goto out_gid;
  
  	p = xdr_decode_size3(p, &fattr->size);
  	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
  	p = xdr_decode_specdata3(p, &fattr->rdev);
  
  	p = xdr_decode_hyper(p, &fattr->fsid.major);
  	fattr->fsid.minor = 0;
  
  	p = xdr_decode_fileid3(p, &fattr->fileid);
  	p = xdr_decode_nfstime3(p, &fattr->atime);
  	p = xdr_decode_nfstime3(p, &fattr->mtime);
  	xdr_decode_nfstime3(p, &fattr->ctime);
  	fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
  
  	fattr->valid |= NFS_ATTR_FATTR_V3;
  	return 0;
  out_uid:
  	dprintk("NFS: returned invalid uid
  ");
  	return -EINVAL;
  out_gid:
  	dprintk("NFS: returned invalid gid
  ");
  	return -EINVAL;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * post_op_attr
   *
   *	union post_op_attr switch (bool attributes_follow) {
   *	case TRUE:
   *		fattr3	attributes;
   *	case FALSE:
   *		void;
   *	};
   */
  static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	if (*p != xdr_zero)
  		return decode_fattr3(xdr, fattr);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * wcc_attr
   *	struct wcc_attr {
   *		size3		size;
   *		nfstime3	mtime;
   *		nfstime3	ctime;
   *	};
   */
  static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  
  	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
  		| NFS_ATTR_FATTR_PRECHANGE
  		| NFS_ATTR_FATTR_PREMTIME
  		| NFS_ATTR_FATTR_PRECTIME;
  
  	p = xdr_decode_size3(p, &fattr->pre_size);
  	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
  	xdr_decode_nfstime3(p, &fattr->pre_ctime);
  	fattr->pre_change_attr = nfs_timespec_to_change_attr(&fattr->pre_ctime);
  
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * pre_op_attr
   *	union pre_op_attr switch (bool attributes_follow) {
   *	case TRUE:
   *		wcc_attr	attributes;
   *	case FALSE:
   *		void;
   *	};
   *
   * wcc_data
   *
   *	struct wcc_data {
   *		pre_op_attr	before;
   *		post_op_attr	after;
   *	};
   */
  static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	if (*p != xdr_zero)
  		return decode_wcc_attr(xdr, fattr);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr)
  {
  	int error;
  
  	error = decode_pre_op_attr(xdr, fattr);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, fattr);
  out:
  	return error;
  }
  
  /*
   * post_op_fh3
   *
   *	union post_op_fh3 switch (bool handle_follows) {
   *	case TRUE:
   *		nfs_fh3  handle;
   *	case FALSE:
   *		void;
   *	};
   */
  static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
  {
  	__be32 *p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	if (*p != xdr_zero)
  		return decode_nfs_fh3(xdr, fh);
  	zero_nfs_fh3(fh);
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  /*
   * diropargs3
   *
   *	struct diropargs3 {
   *		nfs_fh3		dir;
   *		filename3	name;
   *	};
   */
  static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
  			      const char *name, u32 length)
  {
  	encode_nfs_fh3(xdr, fh);
  	encode_filename3(xdr, name, length);
  }
  
  
  /*
   * NFSv3 XDR encode functions
   *
   * NFSv3 argument types are defined in section 3.3 of RFC 1813:
   * "NFS Version 3 Protocol Specification".
   */
  
  /*
   * 3.3.1  GETATTR3args
   *
   *	struct GETATTR3args {
   *		nfs_fh3  object;
   *	};
   */
  static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
  				      struct xdr_stream *xdr,
  				      const struct nfs_fh *fh)
  {
  	encode_nfs_fh3(xdr, fh);
  }
  
  /*
   * 3.3.2  SETATTR3args
   *
   *	union sattrguard3 switch (bool check) {
   *	case TRUE:
   *		nfstime3  obj_ctime;
   *	case FALSE:
   *		void;
   *	};
   *
   *	struct SETATTR3args {
   *		nfs_fh3		object;
   *		sattr3		new_attributes;
   *		sattrguard3	guard;
   *	};
   */
  static void encode_sattrguard3(struct xdr_stream *xdr,
  			       const struct nfs3_sattrargs *args)
  {
  	__be32 *p;
  
  	if (args->guard) {
  		p = xdr_reserve_space(xdr, 4 + 8);
  		*p++ = xdr_one;
  		xdr_encode_nfstime3(p, &args->guardtime);
  	} else {
  		p = xdr_reserve_space(xdr, 4);
  		*p = xdr_zero;
  	}
  }
  
  static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
  				      struct xdr_stream *xdr,
  				      const struct nfs3_sattrargs *args)
  {
  	encode_nfs_fh3(xdr, args->fh);
  	encode_sattr3(xdr, args->sattr);
  	encode_sattrguard3(xdr, args);
  }
  
  /*
   * 3.3.3  LOOKUP3args
   *
   *	struct LOOKUP3args {
   *		diropargs3  what;
   *	};
   */
  static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs3_diropargs *args)
  {
  	encode_diropargs3(xdr, args->fh, args->name, args->len);
  }
  
  /*
   * 3.3.4  ACCESS3args
   *
   *	struct ACCESS3args {
   *		nfs_fh3		object;
   *		uint32		access;
   *	};
   */
  static void encode_access3args(struct xdr_stream *xdr,
  			       const struct nfs3_accessargs *args)
  {
  	encode_nfs_fh3(xdr, args->fh);
  	encode_uint32(xdr, args->access);
  }
  
  static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs3_accessargs *args)
  {
  	encode_access3args(xdr, args);
  }
  
  /*
   * 3.3.5  READLINK3args
   *
   *	struct READLINK3args {
   *		nfs_fh3	symlink;
   *	};
   */
  static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
  				       struct xdr_stream *xdr,
  				       const struct nfs3_readlinkargs *args)
  {
  	encode_nfs_fh3(xdr, args->fh);
  	prepare_reply_buffer(req, args->pages, args->pgbase,
  					args->pglen, NFS3_readlinkres_sz);
  }
  
  /*
   * 3.3.6  READ3args
   *
   *	struct READ3args {
   *		nfs_fh3		file;
   *		offset3		offset;
   *		count3		count;
   *	};
   */
  static void encode_read3args(struct xdr_stream *xdr,
  			     const struct nfs_readargs *args)
  {
  	__be32 *p;
  
  	encode_nfs_fh3(xdr, args->fh);
  
  	p = xdr_reserve_space(xdr, 8 + 4);
  	p = xdr_encode_hyper(p, args->offset);
  	*p = cpu_to_be32(args->count);
  }
  
  static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   const struct nfs_readargs *args)
  {
  	encode_read3args(xdr, args);
  	prepare_reply_buffer(req, args->pages, args->pgbase,
  					args->count, NFS3_readres_sz);
  	req->rq_rcv_buf.flags |= XDRBUF_READ;
  }
  
  /*
   * 3.3.7  WRITE3args
   *
   *	enum stable_how {
   *		UNSTABLE  = 0,
   *		DATA_SYNC = 1,
   *		FILE_SYNC = 2
   *	};
   *
   *	struct WRITE3args {
   *		nfs_fh3		file;
   *		offset3		offset;
   *		count3		count;
   *		stable_how	stable;
   *		opaque		data<>;
   *	};
   */
  static void encode_write3args(struct xdr_stream *xdr,
  			      const struct nfs_writeargs *args)
  {
  	__be32 *p;
  
  	encode_nfs_fh3(xdr, args->fh);
  
  	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
  	p = xdr_encode_hyper(p, args->offset);
  	*p++ = cpu_to_be32(args->count);
  	*p++ = cpu_to_be32(args->stable);
  	*p = cpu_to_be32(args->count);
  	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
  }
  
  static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    const struct nfs_writeargs *args)
  {
  	encode_write3args(xdr, args);
  	xdr->buf->flags |= XDRBUF_WRITE;
  }
  
  /*
   * 3.3.8  CREATE3args
   *
   *	enum createmode3 {
   *		UNCHECKED = 0,
   *		GUARDED   = 1,
   *		EXCLUSIVE = 2
   *	};
   *
   *	union createhow3 switch (createmode3 mode) {
   *	case UNCHECKED:
   *	case GUARDED:
   *		sattr3       obj_attributes;
   *	case EXCLUSIVE:
   *		createverf3  verf;
   *	};
   *
   *	struct CREATE3args {
   *		diropargs3	where;
   *		createhow3	how;
   *	};
   */
  static void encode_createhow3(struct xdr_stream *xdr,
  			      const struct nfs3_createargs *args)
  {
  	encode_uint32(xdr, args->createmode);
  	switch (args->createmode) {
  	case NFS3_CREATE_UNCHECKED:
  	case NFS3_CREATE_GUARDED:
  		encode_sattr3(xdr, args->sattr);
  		break;
  	case NFS3_CREATE_EXCLUSIVE:
  		encode_createverf3(xdr, args->verifier);
  		break;
  	default:
  		BUG();
  	}
  }
  
  static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs3_createargs *args)
  {
  	encode_diropargs3(xdr, args->fh, args->name, args->len);
  	encode_createhow3(xdr, args);
  }
  
  /*
   * 3.3.9  MKDIR3args
   *
   *	struct MKDIR3args {
   *		diropargs3	where;
   *		sattr3		attributes;
   *	};
   */
  static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    const struct nfs3_mkdirargs *args)
  {
  	encode_diropargs3(xdr, args->fh, args->name, args->len);
  	encode_sattr3(xdr, args->sattr);
  }
  
  /*
   * 3.3.10  SYMLINK3args
   *
   *	struct symlinkdata3 {
   *		sattr3		symlink_attributes;
   *		nfspath3	symlink_data;
   *	};
   *
   *	struct SYMLINK3args {
   *		diropargs3	where;
   *		symlinkdata3	symlink;
   *	};
   */
  static void encode_symlinkdata3(struct xdr_stream *xdr,
  				const struct nfs3_symlinkargs *args)
  {
  	encode_sattr3(xdr, args->sattr);
  	encode_nfspath3(xdr, args->pages, args->pathlen);
  }
  
  static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
  				      struct xdr_stream *xdr,
  				      const struct nfs3_symlinkargs *args)
  {
  	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
  	encode_symlinkdata3(xdr, args);
  }
  
  /*
   * 3.3.11  MKNOD3args
   *
   *	struct devicedata3 {
   *		sattr3		dev_attributes;
   *		specdata3	spec;
   *	};
   *
   *	union mknoddata3 switch (ftype3 type) {
   *	case NF3CHR:
   *	case NF3BLK:
   *		devicedata3	device;
   *	case NF3SOCK:
   *	case NF3FIFO:
   *		sattr3		pipe_attributes;
   *	default:
   *		void;
   *	};
   *
   *	struct MKNOD3args {
   *		diropargs3	where;
   *		mknoddata3	what;
   *	};
   */
  static void encode_devicedata3(struct xdr_stream *xdr,
  			       const struct nfs3_mknodargs *args)
  {
  	encode_sattr3(xdr, args->sattr);
  	encode_specdata3(xdr, args->rdev);
  }
  
  static void encode_mknoddata3(struct xdr_stream *xdr,
  			      const struct nfs3_mknodargs *args)
  {
  	encode_ftype3(xdr, args->type);
  	switch (args->type) {
  	case NF3CHR:
  	case NF3BLK:
  		encode_devicedata3(xdr, args);
  		break;
  	case NF3SOCK:
  	case NF3FIFO:
  		encode_sattr3(xdr, args->sattr);
  		break;
  	case NF3REG:
  	case NF3DIR:
  		break;
  	default:
  		BUG();
  	}
  }
  
  static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    const struct nfs3_mknodargs *args)
  {
  	encode_diropargs3(xdr, args->fh, args->name, args->len);
  	encode_mknoddata3(xdr, args);
  }
  
  /*
   * 3.3.12  REMOVE3args
   *
   *	struct REMOVE3args {
   *		diropargs3  object;
   *	};
   */
  static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs_removeargs *args)
  {
  	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
  }
  
  /*
   * 3.3.14  RENAME3args
   *
   *	struct RENAME3args {
   *		diropargs3	from;
   *		diropargs3	to;
   *	};
   */
  static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs_renameargs *args)
  {
  	const struct qstr *old = args->old_name;
  	const struct qstr *new = args->new_name;
  
  	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
  	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
  }
  
  /*
   * 3.3.15  LINK3args
   *
   *	struct LINK3args {
   *		nfs_fh3		file;
   *		diropargs3	link;
   *	};
   */
  static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   const struct nfs3_linkargs *args)
  {
  	encode_nfs_fh3(xdr, args->fromfh);
  	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
  }
  
  /*
   * 3.3.16  READDIR3args
   *
   *	struct READDIR3args {
   *		nfs_fh3		dir;
   *		cookie3		cookie;
   *		cookieverf3	cookieverf;
   *		count3		count;
   *	};
   */
  static void encode_readdir3args(struct xdr_stream *xdr,
  				const struct nfs3_readdirargs *args)
  {
  	__be32 *p;
  
  	encode_nfs_fh3(xdr, args->fh);
  
  	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
  	p = xdr_encode_cookie3(p, args->cookie);
  	p = xdr_encode_cookieverf3(p, args->verf);
  	*p = cpu_to_be32(args->count);
  }
  
  static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
  				      struct xdr_stream *xdr,
  				      const struct nfs3_readdirargs *args)
  {
  	encode_readdir3args(xdr, args);
  	prepare_reply_buffer(req, args->pages, 0,
  				args->count, NFS3_readdirres_sz);
  }
  
  /*
   * 3.3.17  READDIRPLUS3args
   *
   *	struct READDIRPLUS3args {
   *		nfs_fh3		dir;
   *		cookie3		cookie;
   *		cookieverf3	cookieverf;
   *		count3		dircount;
   *		count3		maxcount;
   *	};
   */
  static void encode_readdirplus3args(struct xdr_stream *xdr,
  				    const struct nfs3_readdirargs *args)
  {
  	__be32 *p;
  
  	encode_nfs_fh3(xdr, args->fh);
  
  	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4 + 4);
  	p = xdr_encode_cookie3(p, args->cookie);
  	p = xdr_encode_cookieverf3(p, args->verf);
  
  	/*
  	 * readdirplus: need dircount + buffer size.
  	 * We just make sure we make dircount big enough
  	 */
  	*p++ = cpu_to_be32(args->count >> 3);
  
  	*p = cpu_to_be32(args->count);
  }
  
  static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
  					  struct xdr_stream *xdr,
  					  const struct nfs3_readdirargs *args)
  {
  	encode_readdirplus3args(xdr, args);
  	prepare_reply_buffer(req, args->pages, 0,
  				args->count, NFS3_readdirres_sz);
  }
  
  /*
   * 3.3.21  COMMIT3args
   *
   *	struct COMMIT3args {
   *		nfs_fh3		file;
   *		offset3		offset;
   *		count3		count;
   *	};
   */
  static void encode_commit3args(struct xdr_stream *xdr,
  			       const struct nfs_commitargs *args)
  {
  	__be32 *p;
  
  	encode_nfs_fh3(xdr, args->fh);
  
  	p = xdr_reserve_space(xdr, 8 + 4);
  	p = xdr_encode_hyper(p, args->offset);
  	*p = cpu_to_be32(args->count);
  }
  
  static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs_commitargs *args)
  {
  	encode_commit3args(xdr, args);
  }
  
  #ifdef CONFIG_NFS_V3_ACL
  
  static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs3_getaclargs *args)
  {
  	encode_nfs_fh3(xdr, args->fh);
  	encode_uint32(xdr, args->mask);
  	if (args->mask & (NFS_ACL | NFS_DFACL))
  		prepare_reply_buffer(req, args->pages, 0,
  					NFSACL_MAXPAGES << PAGE_SHIFT,
  					ACL3_getaclres_sz);
  }
  
  static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     const struct nfs3_setaclargs *args)
  {
  	unsigned int base;
  	int error;
  
  	encode_nfs_fh3(xdr, NFS_FH(args->inode));
  	encode_uint32(xdr, args->mask);
  
  	base = req->rq_slen;
  	if (args->npages != 0)
  		xdr_write_pages(xdr, args->pages, 0, args->len);
  	else
  		xdr_reserve_space(xdr, NFS_ACL_INLINE_BUFSIZE);
  
  	error = nfsacl_encode(xdr->buf, base, args->inode,
  			    (args->mask & NFS_ACL) ?
  			    args->acl_access : NULL, 1, 0);
  	/* FIXME: this is just broken */
  	BUG_ON(error < 0);
  	error = nfsacl_encode(xdr->buf, base + error, args->inode,
  			    (args->mask & NFS_DFACL) ?
  			    args->acl_default : NULL, 1,
  			    NFS_ACL_DEFAULT);
  	BUG_ON(error < 0);
  }
  
  #endif  /* CONFIG_NFS_V3_ACL */
  
  /*
   * NFSv3 XDR decode functions
   *
   * NFSv3 result types are defined in section 3.3 of RFC 1813:
   * "NFS Version 3 Protocol Specification".
   */
  
  /*
   * 3.3.1  GETATTR3res
   *
   *	struct GETATTR3resok {
   *		fattr3		obj_attributes;
   *	};
   *
   *	union GETATTR3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		GETATTR3resok  resok;
   *	default:
   *		void;
   *	};
   */
  static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    struct nfs_fattr *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_fattr3(xdr, result);
  out:
  	return error;
  out_default:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.2  SETATTR3res
   *
   *	struct SETATTR3resok {
   *		wcc_data  obj_wcc;
   *	};
   *
   *	struct SETATTR3resfail {
   *		wcc_data  obj_wcc;
   *	};
   *
   *	union SETATTR3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		SETATTR3resok   resok;
   *	default:
   *		SETATTR3resfail resfail;
   *	};
   */
  static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    struct nfs_fattr *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.3  LOOKUP3res
   *
   *	struct LOOKUP3resok {
   *		nfs_fh3		object;
   *		post_op_attr	obj_attributes;
   *		post_op_attr	dir_attributes;
   *	};
   *
   *	struct LOOKUP3resfail {
   *		post_op_attr	dir_attributes;
   *	};
   *
   *	union LOOKUP3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		LOOKUP3resok	resok;
   *	default:
   *		LOOKUP3resfail	resfail;
   *	};
   */
  static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs3_diropres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_nfs_fh3(xdr, result->fh);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->dir_attr);
  out:
  	return error;
  out_default:
  	error = decode_post_op_attr(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.4  ACCESS3res
   *
   *	struct ACCESS3resok {
   *		post_op_attr	obj_attributes;
   *		uint32		access;
   *	};
   *
   *	struct ACCESS3resfail {
   *		post_op_attr	obj_attributes;
   *	};
   *
   *	union ACCESS3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		ACCESS3resok	resok;
   *	default:
   *		ACCESS3resfail	resfail;
   *	};
   */
  static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs3_accessres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_uint32(xdr, &result->access);
  out:
  	return error;
  out_default:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.5  READLINK3res
   *
   *	struct READLINK3resok {
   *		post_op_attr	symlink_attributes;
   *		nfspath3	data;
   *	};
   *
   *	struct READLINK3resfail {
   *		post_op_attr	symlink_attributes;
   *	};
   *
   *	union READLINK3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		READLINK3resok	resok;
   *	default:
   *		READLINK3resfail resfail;
   *	};
   */
  static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     struct nfs_fattr *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_nfspath3(xdr);
  out:
  	return error;
  out_default:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.6  READ3res
   *
   *	struct READ3resok {
   *		post_op_attr	file_attributes;
   *		count3		count;
   *		bool		eof;
   *		opaque		data<>;
   *	};
   *
   *	struct READ3resfail {
   *		post_op_attr	file_attributes;
   *	};
   *
   *	union READ3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		READ3resok	resok;
   *	default:
   *		READ3resfail	resfail;
   *	};
   */
  static int decode_read3resok(struct xdr_stream *xdr,
  			     struct nfs_readres *result)
  {
  	u32 eof, count, ocount, recvd;
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4 + 4 + 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	count = be32_to_cpup(p++);
  	eof = be32_to_cpup(p++);
  	ocount = be32_to_cpup(p++);
  	if (unlikely(ocount != count))
  		goto out_mismatch;
  	recvd = xdr_read_pages(xdr, count);
  	if (unlikely(count > recvd))
  		goto out_cheating;
  out:
  	result->eof = eof;
  	result->count = count;
  	return count;
  out_mismatch:
  	dprintk("NFS: READ count doesn't match length of opaque: "
  		"count %u != ocount %u
  ", count, ocount);
  	return -EIO;
  out_cheating:
  	dprintk("NFS: server cheating in read result: "
  		"count %u > recvd %u
  ", count, recvd);
  	count = recvd;
  	eof = 0;
  	goto out;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
  				 struct nfs_readres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_read3resok(xdr, result);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.7  WRITE3res
   *
   *	enum stable_how {
   *		UNSTABLE  = 0,
   *		DATA_SYNC = 1,
   *		FILE_SYNC = 2
   *	};
   *
   *	struct WRITE3resok {
   *		wcc_data	file_wcc;
   *		count3		count;
   *		stable_how	committed;
   *		writeverf3	verf;
   *	};
   *
   *	struct WRITE3resfail {
   *		wcc_data	file_wcc;
   *	};
   *
   *	union WRITE3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		WRITE3resok	resok;
   *	default:
   *		WRITE3resfail	resfail;
   *	};
   */
  static int decode_write3resok(struct xdr_stream *xdr,
  			      struct nfs_writeres *result)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4 + 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	result->count = be32_to_cpup(p++);
  	result->verf->committed = be32_to_cpup(p++);
  	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
  		goto out_badvalue;
  	if (decode_writeverf3(xdr, &result->verf->verifier))
  		goto out_eio;
  	return result->count;
  out_badvalue:
  	dprintk("NFS: bad stable_how value: %u
  ", result->verf->committed);
  	return -EIO;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  out_eio:
  	return -EIO;
  }
  
  static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
  				  struct nfs_writeres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_write3resok(xdr, result);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.8  CREATE3res
   *
   *	struct CREATE3resok {
   *		post_op_fh3	obj;
   *		post_op_attr	obj_attributes;
   *		wcc_data	dir_wcc;
   *	};
   *
   *	struct CREATE3resfail {
   *		wcc_data	dir_wcc;
   *	};
   *
   *	union CREATE3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		CREATE3resok	resok;
   *	default:
   *		CREATE3resfail	resfail;
   *	};
   */
  static int decode_create3resok(struct xdr_stream *xdr,
  			       struct nfs3_diropres *result)
  {
  	int error;
  
  	error = decode_post_op_fh3(xdr, result->fh);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	/* The server isn't required to return a file handle.
  	 * If it didn't, force the client to perform a LOOKUP
  	 * to determine the correct file handle and attribute
  	 * values for the new object. */
  	if (result->fh->size == 0)
  		result->fattr->valid = 0;
  	error = decode_wcc_data(xdr, result->dir_attr);
  out:
  	return error;
  }
  
  static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs3_diropres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_create3resok(xdr, result);
  out:
  	return error;
  out_default:
  	error = decode_wcc_data(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.12  REMOVE3res
   *
   *	struct REMOVE3resok {
   *		wcc_data    dir_wcc;
   *	};
   *
   *	struct REMOVE3resfail {
   *		wcc_data    dir_wcc;
   *	};
   *
   *	union REMOVE3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		REMOVE3resok   resok;
   *	default:
   *		REMOVE3resfail resfail;
   *	};
   */
  static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_removeres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.14  RENAME3res
   *
   *	struct RENAME3resok {
   *		wcc_data	fromdir_wcc;
   *		wcc_data	todir_wcc;
   *	};
   *
   *	struct RENAME3resfail {
   *		wcc_data	fromdir_wcc;
   *		wcc_data	todir_wcc;
   *	};
   *
   *	union RENAME3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		RENAME3resok   resok;
   *	default:
   *		RENAME3resfail resfail;
   *	};
   */
  static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_renameres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->old_fattr);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->new_fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.15  LINK3res
   *
   *	struct LINK3resok {
   *		post_op_attr	file_attributes;
   *		wcc_data	linkdir_wcc;
   *	};
   *
   *	struct LINK3resfail {
   *		post_op_attr	file_attributes;
   *		wcc_data	linkdir_wcc;
   *	};
   *
   *	union LINK3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		LINK3resok	resok;
   *	default:
   *		LINK3resfail	resfail;
   *	};
   */
  static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
  				 struct nfs3_linkres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /**
   * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
   *			the local page cache
   * @xdr: XDR stream where entry resides
   * @entry: buffer to fill in with entry data
   * @plus: boolean indicating whether this should be a readdirplus entry
   *
   * Returns zero if successful, otherwise a negative errno value is
   * returned.
   *
   * This function is not invoked during READDIR reply decoding, but
   * rather whenever an application invokes the getdents(2) system call
   * on a directory already in our cache.
   *
   * 3.3.16  entry3
   *
   *	struct entry3 {
   *		fileid3		fileid;
   *		filename3	name;
   *		cookie3		cookie;
   *		fhandle3	filehandle;
   *		post_op_attr3	attributes;
   *		entry3		*nextentry;
   *	};
   *
   * 3.3.17  entryplus3
   *	struct entryplus3 {
   *		fileid3		fileid;
   *		filename3	name;
   *		cookie3		cookie;
   *		post_op_attr	name_attributes;
   *		post_op_fh3	name_handle;
   *		entryplus3	*nextentry;
   *	};
   */
  int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
  		       int plus)
  {
  	struct nfs_entry old = *entry;
  	__be32 *p;
  	int error;
  
  	p = xdr_inline_decode(xdr, 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	if (*p == xdr_zero) {
  		p = xdr_inline_decode(xdr, 4);
  		if (unlikely(p == NULL))
  			goto out_overflow;
  		if (*p == xdr_zero)
  			return -EAGAIN;
  		entry->eof = 1;
  		return -EBADCOOKIE;
  	}
  
  	error = decode_fileid3(xdr, &entry->ino);
  	if (unlikely(error))
  		return error;
  
  	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
  	if (unlikely(error))
  		return error;
  
  	entry->prev_cookie = entry->cookie;
  	error = decode_cookie3(xdr, &entry->cookie);
  	if (unlikely(error))
  		return error;
  
  	entry->d_type = DT_UNKNOWN;
  
  	if (plus) {
  		entry->fattr->valid = 0;
  		error = decode_post_op_attr(xdr, entry->fattr);
  		if (unlikely(error))
  			return error;
  		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
  			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
  
  		/* In fact, a post_op_fh3: */
  		p = xdr_inline_decode(xdr, 4);
  		if (unlikely(p == NULL))
  			goto out_overflow;
  		if (*p != xdr_zero) {
  			error = decode_nfs_fh3(xdr, entry->fh);
  			if (unlikely(error)) {
  				if (error == -E2BIG)
  					goto out_truncated;
  				return error;
  			}
  		} else
  			zero_nfs_fh3(entry->fh);
  	}
  
  	return 0;
  
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EAGAIN;
  out_truncated:
  	dprintk("NFS: directory entry contains invalid file handle
  ");
  	*entry = old;
  	return -EAGAIN;
  }
  
  /*
   * 3.3.16  READDIR3res
   *
   *	struct dirlist3 {
   *		entry3		*entries;
   *		bool		eof;
   *	};
   *
   *	struct READDIR3resok {
   *		post_op_attr	dir_attributes;
   *		cookieverf3	cookieverf;
   *		dirlist3	reply;
   *	};
   *
   *	struct READDIR3resfail {
   *		post_op_attr	dir_attributes;
   *	};
   *
   *	union READDIR3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		READDIR3resok	resok;
   *	default:
   *		READDIR3resfail	resfail;
   *	};
   *
   * Read the directory contents into the page cache, but otherwise
   * don't touch them.  The actual decoding is done by nfs3_decode_entry()
   * during subsequent nfs_readdir() calls.
   */
  static int decode_dirlist3(struct xdr_stream *xdr)
  {
  	return xdr_read_pages(xdr, xdr->buf->page_len);
  }
  
  static int decode_readdir3resok(struct xdr_stream *xdr,
  				struct nfs3_readdirres *result)
  {
  	int error;
  
  	error = decode_post_op_attr(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	/* XXX: do we need to check if result->verf != NULL ? */
  	error = decode_cookieverf3(xdr, result->verf);
  	if (unlikely(error))
  		goto out;
  	error = decode_dirlist3(xdr);
  out:
  	return error;
  }
  
  static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
  				    struct xdr_stream *xdr,
  				    struct nfs3_readdirres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_readdir3resok(xdr, result);
  out:
  	return error;
  out_default:
  	error = decode_post_op_attr(xdr, result->dir_attr);
  	if (unlikely(error))
  		goto out;
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.18  FSSTAT3res
   *
   *	struct FSSTAT3resok {
   *		post_op_attr	obj_attributes;
   *		size3		tbytes;
   *		size3		fbytes;
   *		size3		abytes;
   *		size3		tfiles;
   *		size3		ffiles;
   *		size3		afiles;
   *		uint32		invarsec;
   *	};
   *
   *	struct FSSTAT3resfail {
   *		post_op_attr	obj_attributes;
   *	};
   *
   *	union FSSTAT3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		FSSTAT3resok	resok;
   *	default:
   *		FSSTAT3resfail	resfail;
   *	};
   */
  static int decode_fsstat3resok(struct xdr_stream *xdr,
  			       struct nfs_fsstat *result)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 8 * 6 + 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	p = xdr_decode_size3(p, &result->tbytes);
  	p = xdr_decode_size3(p, &result->fbytes);
  	p = xdr_decode_size3(p, &result->abytes);
  	p = xdr_decode_size3(p, &result->tfiles);
  	p = xdr_decode_size3(p, &result->ffiles);
  	xdr_decode_size3(p, &result->afiles);
  	/* ignore invarsec */
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_fsstat *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_fsstat3resok(xdr, result);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.19  FSINFO3res
   *
   *	struct FSINFO3resok {
   *		post_op_attr	obj_attributes;
   *		uint32		rtmax;
   *		uint32		rtpref;
   *		uint32		rtmult;
   *		uint32		wtmax;
   *		uint32		wtpref;
   *		uint32		wtmult;
   *		uint32		dtpref;
   *		size3		maxfilesize;
   *		nfstime3	time_delta;
   *		uint32		properties;
   *	};
   *
   *	struct FSINFO3resfail {
   *		post_op_attr	obj_attributes;
   *	};
   *
   *	union FSINFO3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		FSINFO3resok	resok;
   *	default:
   *		FSINFO3resfail	resfail;
   *	};
   */
  static int decode_fsinfo3resok(struct xdr_stream *xdr,
  			       struct nfs_fsinfo *result)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	result->rtmax  = be32_to_cpup(p++);
  	result->rtpref = be32_to_cpup(p++);
  	result->rtmult = be32_to_cpup(p++);
  	result->wtmax  = be32_to_cpup(p++);
  	result->wtpref = be32_to_cpup(p++);
  	result->wtmult = be32_to_cpup(p++);
  	result->dtpref = be32_to_cpup(p++);
  	p = xdr_decode_size3(p, &result->maxfilesize);
  	xdr_decode_nfstime3(p, &result->time_delta);
  
  	/* ignore properties */
  	result->lease_time = 0;
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_fsinfo *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_fsinfo3resok(xdr, result);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.20  PATHCONF3res
   *
   *	struct PATHCONF3resok {
   *		post_op_attr	obj_attributes;
   *		uint32		linkmax;
   *		uint32		name_max;
   *		bool		no_trunc;
   *		bool		chown_restricted;
   *		bool		case_insensitive;
   *		bool		case_preserving;
   *	};
   *
   *	struct PATHCONF3resfail {
   *		post_op_attr	obj_attributes;
   *	};
   *
   *	union PATHCONF3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		PATHCONF3resok	resok;
   *	default:
   *		PATHCONF3resfail resfail;
   *	};
   */
  static int decode_pathconf3resok(struct xdr_stream *xdr,
  				 struct nfs_pathconf *result)
  {
  	__be32 *p;
  
  	p = xdr_inline_decode(xdr, 4 * 6);
  	if (unlikely(p == NULL))
  		goto out_overflow;
  	result->max_link = be32_to_cpup(p++);
  	result->max_namelen = be32_to_cpup(p);
  	/* ignore remaining fields */
  	return 0;
  out_overflow:
  	print_overflow_msg(__func__, xdr);
  	return -EIO;
  }
  
  static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
  				     struct xdr_stream *xdr,
  				     struct nfs_pathconf *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_pathconf3resok(xdr, result);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  /*
   * 3.3.21  COMMIT3res
   *
   *	struct COMMIT3resok {
   *		wcc_data	file_wcc;
   *		writeverf3	verf;
   *	};
   *
   *	struct COMMIT3resfail {
   *		wcc_data	file_wcc;
   *	};
   *
   *	union COMMIT3res switch (nfsstat3 status) {
   *	case NFS3_OK:
   *		COMMIT3resok	resok;
   *	default:
   *		COMMIT3resfail	resfail;
   *	};
   */
  static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_commitres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	error = decode_wcc_data(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_status;
  	error = decode_writeverf3(xdr, &result->verf->verifier);
  out:
  	return error;
  out_status:
  	return nfs3_stat_to_errno(status);
  }
  
  #ifdef CONFIG_NFS_V3_ACL
  
  static inline int decode_getacl3resok(struct xdr_stream *xdr,
  				      struct nfs3_getaclres *result)
  {
  	struct posix_acl **acl;
  	unsigned int *aclcnt;
  	size_t hdrlen;
  	int error;
  
  	error = decode_post_op_attr(xdr, result->fattr);
  	if (unlikely(error))
  		goto out;
  	error = decode_uint32(xdr, &result->mask);
  	if (unlikely(error))
  		goto out;
  	error = -EINVAL;
  	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
  		goto out;
  
  	hdrlen = xdr_stream_pos(xdr);
  
  	acl = NULL;
  	if (result->mask & NFS_ACL)
  		acl = &result->acl_access;
  	aclcnt = NULL;
  	if (result->mask & NFS_ACLCNT)
  		aclcnt = &result->acl_access_count;
  	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
  	if (unlikely(error <= 0))
  		goto out;
  
  	acl = NULL;
  	if (result->mask & NFS_DFACL)
  		acl = &result->acl_default;
  	aclcnt = NULL;
  	if (result->mask & NFS_DFACLCNT)
  		aclcnt = &result->acl_default_count;
  	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
  	if (unlikely(error <= 0))
  		return error;
  	error = 0;
  out:
  	return error;
  }
  
  static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs3_getaclres *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_getacl3resok(xdr, result);
  out:
  	return error;
  out_default:
  	return nfs3_stat_to_errno(status);
  }
  
  static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
  				   struct xdr_stream *xdr,
  				   struct nfs_fattr *result)
  {
  	enum nfs_stat status;
  	int error;
  
  	error = decode_nfsstat3(xdr, &status);
  	if (unlikely(error))
  		goto out;
  	if (status != NFS3_OK)
  		goto out_default;
  	error = decode_post_op_attr(xdr, result);
  out:
  	return error;
  out_default:
  	return nfs3_stat_to_errno(status);
  }
  
  #endif  /* CONFIG_NFS_V3_ACL */
  
  
  /*
   * We need to translate between nfs status return values and
   * the local errno values which may not be the same.
   */
  static const struct {
  	int stat;
  	int errno;
  } nfs_errtbl[] = {
  	{ NFS_OK,		0		},
  	{ NFSERR_PERM,		-EPERM		},
  	{ NFSERR_NOENT,		-ENOENT		},
  	{ NFSERR_IO,		-errno_NFSERR_IO},
  	{ NFSERR_NXIO,		-ENXIO		},
  /*	{ NFSERR_EAGAIN,	-EAGAIN		}, */
  	{ NFSERR_ACCES,		-EACCES		},
  	{ NFSERR_EXIST,		-EEXIST		},
  	{ NFSERR_XDEV,		-EXDEV		},
  	{ NFSERR_NODEV,		-ENODEV		},
  	{ NFSERR_NOTDIR,	-ENOTDIR	},
  	{ NFSERR_ISDIR,		-EISDIR		},
  	{ NFSERR_INVAL,		-EINVAL		},
  	{ NFSERR_FBIG,		-EFBIG		},
  	{ NFSERR_NOSPC,		-ENOSPC		},
  	{ NFSERR_ROFS,		-EROFS		},
  	{ NFSERR_MLINK,		-EMLINK		},
  	{ NFSERR_NAMETOOLONG,	-ENAMETOOLONG	},
  	{ NFSERR_NOTEMPTY,	-ENOTEMPTY	},
  	{ NFSERR_DQUOT,		-EDQUOT		},
  	{ NFSERR_STALE,		-ESTALE		},
  	{ NFSERR_REMOTE,	-EREMOTE	},
  #ifdef EWFLUSH
  	{ NFSERR_WFLUSH,	-EWFLUSH	},
  #endif
  	{ NFSERR_BADHANDLE,	-EBADHANDLE	},
  	{ NFSERR_NOT_SYNC,	-ENOTSYNC	},
  	{ NFSERR_BAD_COOKIE,	-EBADCOOKIE	},
  	{ NFSERR_NOTSUPP,	-ENOTSUPP	},
  	{ NFSERR_TOOSMALL,	-ETOOSMALL	},
  	{ NFSERR_SERVERFAULT,	-EREMOTEIO	},
  	{ NFSERR_BADTYPE,	-EBADTYPE	},
  	{ NFSERR_JUKEBOX,	-EJUKEBOX	},
  	{ -1,			-EIO		}
  };
  
  /**
   * nfs3_stat_to_errno - convert an NFS status code to a local errno
   * @status: NFS status code to convert
   *
   * Returns a local errno value, or -EIO if the NFS status code is
   * not recognized.  This function is used jointly by NFSv2 and NFSv3.
   */
  static int nfs3_stat_to_errno(enum nfs_stat status)
  {
  	int i;
  
  	for (i = 0; nfs_errtbl[i].stat != -1; i++) {
  		if (nfs_errtbl[i].stat == (int)status)
  			return nfs_errtbl[i].errno;
  	}
  	dprintk("NFS: Unrecognized nfs status value: %u
  ", status);
  	return nfs_errtbl[i].errno;
  }
  
  
  #define PROC(proc, argtype, restype, timer)				\
  [NFS3PROC_##proc] = {							\
  	.p_proc      = NFS3PROC_##proc,					\
  	.p_encode    = (kxdreproc_t)nfs3_xdr_enc_##argtype##3args,	\
  	.p_decode    = (kxdrdproc_t)nfs3_xdr_dec_##restype##3res,	\
  	.p_arglen    = NFS3_##argtype##args_sz,				\
  	.p_replen    = NFS3_##restype##res_sz,				\
  	.p_timer     = timer,						\
  	.p_statidx   = NFS3PROC_##proc,					\
  	.p_name      = #proc,						\
  	}
  
  struct rpc_procinfo	nfs3_procedures[] = {
  	PROC(GETATTR,		getattr,	getattr,	1),
  	PROC(SETATTR,		setattr,	setattr,	0),
  	PROC(LOOKUP,		lookup,		lookup,		2),
  	PROC(ACCESS,		access,		access,		1),
  	PROC(READLINK,		readlink,	readlink,	3),
  	PROC(READ,		read,		read,		3),
  	PROC(WRITE,		write,		write,		4),
  	PROC(CREATE,		create,		create,		0),
  	PROC(MKDIR,		mkdir,		create,		0),
  	PROC(SYMLINK,		symlink,	create,		0),
  	PROC(MKNOD,		mknod,		create,		0),
  	PROC(REMOVE,		remove,		remove,		0),
  	PROC(RMDIR,		lookup,		setattr,	0),
  	PROC(RENAME,		rename,		rename,		0),
  	PROC(LINK,		link,		link,		0),
  	PROC(READDIR,		readdir,	readdir,	3),
  	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
  	PROC(FSSTAT,		getattr,	fsstat,		0),
  	PROC(FSINFO,		getattr,	fsinfo,		0),
  	PROC(PATHCONF,		getattr,	pathconf,	0),
  	PROC(COMMIT,		commit,		commit,		5),
  };
  
  const struct rpc_version nfs_version3 = {
  	.number			= 3,
  	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
  	.procs			= nfs3_procedures
  };
  
  #ifdef CONFIG_NFS_V3_ACL
  static struct rpc_procinfo	nfs3_acl_procedures[] = {
  	[ACLPROC3_GETACL] = {
  		.p_proc = ACLPROC3_GETACL,
  		.p_encode = (kxdreproc_t)nfs3_xdr_enc_getacl3args,
  		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_getacl3res,
  		.p_arglen = ACL3_getaclargs_sz,
  		.p_replen = ACL3_getaclres_sz,
  		.p_timer = 1,
  		.p_name = "GETACL",
  	},
  	[ACLPROC3_SETACL] = {
  		.p_proc = ACLPROC3_SETACL,
  		.p_encode = (kxdreproc_t)nfs3_xdr_enc_setacl3args,
  		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_setacl3res,
  		.p_arglen = ACL3_setaclargs_sz,
  		.p_replen = ACL3_setaclres_sz,
  		.p_timer = 0,
  		.p_name = "SETACL",
  	},
  };
  
  const struct rpc_version nfsacl_version3 = {
  	.number			= 3,
  	.nrprocs		= sizeof(nfs3_acl_procedures)/
  				  sizeof(nfs3_acl_procedures[0]),
  	.procs			= nfs3_acl_procedures,
  };
  #endif  /* CONFIG_NFS_V3_ACL */