nfs4xdr.c

 * Encode a READLINK request
 */
static int nfs4_xdr_enc_readlink(struct rpc_rqst *req, __be32 *p, const struct nfs4_readlink *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_readlink(&xdr, args, req, &hdr);

	xdr_inline_pages(&req->rq_rcv_buf, hdr.replen << 2, args->pages,
			args->pgbase, args->pglen);
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode a READDIR request
 */
static int nfs4_xdr_enc_readdir(struct rpc_rqst *req, __be32 *p, const struct nfs4_readdir_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_readdir(&xdr, args, req, &hdr);

	xdr_inline_pages(&req->rq_rcv_buf, hdr.replen << 2, args->pages,
			 args->pgbase, args->count);
	dprintk("%s: inlined page args = (%u, %p, %u, %u)\n",
			__func__, hdr.replen << 2, args->pages,
			args->pgbase, args->count);
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode a READ request
 */
static int nfs4_xdr_enc_read(struct rpc_rqst *req, __be32 *p, struct nfs_readargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_read(&xdr, args, &hdr);

	xdr_inline_pages(&req->rq_rcv_buf, hdr.replen << 2,
			 args->pages, args->pgbase, args->count);
	req->rq_rcv_buf.flags |= XDRBUF_READ;
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode an SETATTR request
 */
static int nfs4_xdr_enc_setattr(struct rpc_rqst *req, __be32 *p, struct nfs_setattrargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_setattr(&xdr, args, args->server, &hdr);
	encode_getfattr(&xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode a GETACL request
 */
static int
nfs4_xdr_enc_getacl(struct rpc_rqst *req, __be32 *p,
		struct nfs_getaclargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};
	uint32_t replen;

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	replen = hdr.replen + nfs4_fattr_bitmap_maxsz + 1;
	encode_getattr_two(&xdr, FATTR4_WORD0_ACL, 0, &hdr);

	xdr_inline_pages(&req->rq_rcv_buf, replen << 2,
		args->acl_pages, args->acl_pgbase, args->acl_len);
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode a WRITE request
 */
static int nfs4_xdr_enc_write(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_write(&xdr, args, &hdr);
	req->rq_snd_buf.flags |= XDRBUF_WRITE;
	encode_getfattr(&xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 *  a COMMIT request
 */
static int nfs4_xdr_enc_commit(struct rpc_rqst *req, __be32 *p, struct nfs_writeargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_commit(&xdr, args, &hdr);
	encode_getfattr(&xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * FSINFO request
 */
static int nfs4_xdr_enc_fsinfo(struct rpc_rqst *req, __be32 *p, struct nfs4_fsinfo_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_fsinfo(&xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a PATHCONF request
 */
static int nfs4_xdr_enc_pathconf(struct rpc_rqst *req, __be32 *p, const struct nfs4_pathconf_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_getattr_one(&xdr, args->bitmask[0] & nfs4_pathconf_bitmap[0],
			   &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a STATFS request
 */
static int nfs4_xdr_enc_statfs(struct rpc_rqst *req, __be32 *p, const struct nfs4_statfs_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fh, &hdr);
	encode_getattr_two(&xdr, args->bitmask[0] & nfs4_statfs_bitmap[0],
			   args->bitmask[1] & nfs4_statfs_bitmap[1], &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * GETATTR_BITMAP request
 */
static int nfs4_xdr_enc_server_caps(struct rpc_rqst *req, __be32 *p,
				    struct nfs4_server_caps_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fhandle, &hdr);
	encode_getattr_one(&xdr, FATTR4_WORD0_SUPPORTED_ATTRS|
			   FATTR4_WORD0_LINK_SUPPORT|
			   FATTR4_WORD0_SYMLINK_SUPPORT|
			   FATTR4_WORD0_ACLSUPPORT, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a RENEW request
 */
static int nfs4_xdr_enc_renew(struct rpc_rqst *req, __be32 *p, struct nfs_client *clp)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.nops	= 0,
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_renew(&xdr, clp, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a SETCLIENTID request
 */
static int nfs4_xdr_enc_setclientid(struct rpc_rqst *req, __be32 *p, struct nfs4_setclientid *sc)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.nops	= 0,
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_setclientid(&xdr, sc, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a SETCLIENTID_CONFIRM request
 */
static int nfs4_xdr_enc_setclientid_confirm(struct rpc_rqst *req, __be32 *p, struct nfs_client *clp)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.nops	= 0,
	};
	const u32 lease_bitmap[2] = { FATTR4_WORD0_LEASE_TIME, 0 };

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_setclientid_confirm(&xdr, clp, &hdr);
	encode_putrootfh(&xdr, &hdr);
	encode_fsinfo(&xdr, lease_bitmap, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * DELEGRETURN request
 */
static int nfs4_xdr_enc_delegreturn(struct rpc_rqst *req, __be32 *p, const struct nfs4_delegreturnargs *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->fhandle, &hdr);
	encode_delegreturn(&xdr, args->stateid, &hdr);
	encode_getfattr(&xdr, args->bitmask, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * Encode FS_LOCATIONS request
 */
static int nfs4_xdr_enc_fs_locations(struct rpc_rqst *req, __be32 *p, struct nfs4_fs_locations_arg *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
	};
	uint32_t replen;

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->seq_args, &hdr);
	encode_putfh(&xdr, args->dir_fh, &hdr);
	encode_lookup(&xdr, args->name, &hdr);
	replen = hdr.replen;	/* get the attribute into args->page */
	encode_fs_locations(&xdr, args->bitmask, &hdr);

	xdr_inline_pages(&req->rq_rcv_buf, replen << 2, &args->page,
			0, PAGE_SIZE);
	encode_nops(&hdr);
	return 0;
}

#if defined(CONFIG_NFS_V4_1)
/*
 * EXCHANGE_ID request
 */
static int nfs4_xdr_enc_exchange_id(struct rpc_rqst *req, uint32_t *p,
				    struct nfs41_exchange_id_args *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = args->client->cl_minorversion,
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_exchange_id(&xdr, args, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a CREATE_SESSION request
 */
static int nfs4_xdr_enc_create_session(struct rpc_rqst *req, uint32_t *p,
				       struct nfs41_create_session_args *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = args->client->cl_minorversion,
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_create_session(&xdr, args, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a DESTROY_SESSION request
 */
static int nfs4_xdr_enc_destroy_session(struct rpc_rqst *req, uint32_t *p,
					struct nfs4_session *session)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = session->clp->cl_minorversion,
	};

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_destroy_session(&xdr, session, &hdr);
	encode_nops(&hdr);
	return 0;
}

/*
 * a GET_LEASE_TIME request
 */
static int nfs4_xdr_enc_get_lease_time(struct rpc_rqst *req, uint32_t *p,
				       struct nfs4_get_lease_time_args *args)
{
	struct xdr_stream xdr;
	struct compound_hdr hdr = {
		.minorversion = nfs4_xdr_minorversion(&args->la_seq_args),
	};
	const u32 lease_bitmap[2] = { FATTR4_WORD0_LEASE_TIME, 0 };

	xdr_init_encode(&xdr, &req->rq_snd_buf, p);
	encode_compound_hdr(&xdr, req, &hdr);
	encode_sequence(&xdr, &args->la_seq_args, &hdr);
	encode_putrootfh(&xdr, &hdr);
	encode_fsinfo(&xdr, lease_bitmap, &hdr);
	encode_nops(&hdr);
	return 0;
}
#endif /* CONFIG_NFS_V4_1 */

/*
 * START OF "GENERIC" DECODE ROUTINES.
 *   These may look a little ugly since they are imported from a "generic"
 * set of XDR encode/decode routines which are intended to be shared by
 * all of our NFSv4 implementations (OpenBSD, MacOS X...).
 *
 * If the pain of reading these is too great, it should be a straightforward
 * task to translate them into Linux-specific versions which are more
 * consistent with the style used in NFSv2/v3...
 */
#define READ32(x)         (x) = ntohl(*p++)
#define READ64(x)         do {			\
	(x) = (u64)ntohl(*p++) << 32;		\
	(x) |= ntohl(*p++);			\
} while (0)
#define READTIME(x)       do {			\
	p++;					\
	(x.tv_sec) = ntohl(*p++);		\
	(x.tv_nsec) = ntohl(*p++);		\
} while (0)
#define COPYMEM(x,nbytes) do {			\
	memcpy((x), p, nbytes);			\
	p += XDR_QUADLEN(nbytes);		\
} while (0)

#define READ_BUF(nbytes)  do { \
	p = xdr_inline_decode(xdr, nbytes); \
	if (unlikely(!p)) { \
		dprintk("nfs: %s: prematurely hit end of receive" \
				" buffer\n", __func__); \
		dprintk("nfs: %s: xdr->p=%p, bytes=%u, xdr->end=%p\n", \
				__func__, xdr->p, nbytes, xdr->end); \
		return -EIO; \
	} \
} while (0)

static int decode_opaque_inline(struct xdr_stream *xdr, unsigned int *len, char **string)
{
	__be32 *p;

	READ_BUF(4);
	READ32(*len);
	READ_BUF(*len);
	*string = (char *)p;
	return 0;
}

static int decode_compound_hdr(struct xdr_stream *xdr, struct compound_hdr *hdr)
{
	__be32 *p;

	READ_BUF(8);
	READ32(hdr->status);
	READ32(hdr->taglen);

	READ_BUF(hdr->taglen + 4);
	hdr->tag = (char *)p;
	p += XDR_QUADLEN(hdr->taglen);
	READ32(hdr->nops);
	if (unlikely(hdr->nops < 1))
		return nfs4_stat_to_errno(hdr->status);
	return 0;
}

static int decode_op_hdr(struct xdr_stream *xdr, enum nfs_opnum4 expected)
{
	__be32 *p;
	uint32_t opnum;
	int32_t nfserr;

	READ_BUF(8);
	READ32(opnum);
	if (opnum != expected) {
		dprintk("nfs: Server returned operation"
			" %d but we issued a request for %d\n",
				opnum, expected);
		return -EIO;
	}
	READ32(nfserr);
	if (nfserr != NFS_OK)
		return nfs4_stat_to_errno(nfserr);
	return 0;
}

/* Dummy routine */
static int decode_ace(struct xdr_stream *xdr, void *ace, struct nfs_client *clp)
{
	__be32 *p;
	unsigned int strlen;
	char *str;

	READ_BUF(12);
	return decode_opaque_inline(xdr, &strlen, &str);
}

static int decode_attr_bitmap(struct xdr_stream *xdr, uint32_t *bitmap)
{
	uint32_t bmlen;
	__be32 *p;

	READ_BUF(4);
	READ32(bmlen);

	bitmap[0] = bitmap[1] = 0;
	READ_BUF((bmlen << 2));
	if (bmlen > 0) {
		READ32(bitmap[0]);
		if (bmlen > 1)
			READ32(bitmap[1]);
	}
	return 0;
}

static inline int decode_attr_length(struct xdr_stream *xdr, uint32_t *attrlen, __be32 **savep)
{
	__be32 *p;

	READ_BUF(4);
	READ32(*attrlen);
	*savep = xdr->p;
	return 0;
}

static int decode_attr_supported(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *bitmask)
{
	if (likely(bitmap[0] & FATTR4_WORD0_SUPPORTED_ATTRS)) {
		decode_attr_bitmap(xdr, bitmask);
		bitmap[0] &= ~FATTR4_WORD0_SUPPORTED_ATTRS;
	} else
		bitmask[0] = bitmask[1] = 0;
	dprintk("%s: bitmask=%08x:%08x\n", __func__, bitmask[0], bitmask[1]);
	return 0;
}

static int decode_attr_type(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *type)
{
	__be32 *p;
	int ret = 0;

	*type = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_TYPE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_TYPE)) {
		READ_BUF(4);
		READ32(*type);
		if (*type < NF4REG || *type > NF4NAMEDATTR) {
			dprintk("%s: bad type %d\n", __func__, *type);
			return -EIO;
		}
		bitmap[0] &= ~FATTR4_WORD0_TYPE;
		ret = NFS_ATTR_FATTR_TYPE;
	}
	dprintk("%s: type=0%o\n", __func__, nfs_type2fmt[*type]);
	return ret;
}

static int decode_attr_change(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *change)
{
	__be32 *p;
	int ret = 0;

	*change = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_CHANGE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_CHANGE)) {
		READ_BUF(8);
		READ64(*change);
		bitmap[0] &= ~FATTR4_WORD0_CHANGE;
		ret = NFS_ATTR_FATTR_CHANGE;
	}
	dprintk("%s: change attribute=%Lu\n", __func__,
			(unsigned long long)*change);
	return ret;
}

static int decode_attr_size(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *size)
{
	__be32 *p;
	int ret = 0;

	*size = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_SIZE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_SIZE)) {
		READ_BUF(8);
		READ64(*size);
		bitmap[0] &= ~FATTR4_WORD0_SIZE;
		ret = NFS_ATTR_FATTR_SIZE;
	}
	dprintk("%s: file size=%Lu\n", __func__, (unsigned long long)*size);
	return ret;
}

static int decode_attr_link_support(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_LINK_SUPPORT - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_LINK_SUPPORT)) {
		READ_BUF(4);
		READ32(*res);
		bitmap[0] &= ~FATTR4_WORD0_LINK_SUPPORT;
	}
	dprintk("%s: link support=%s\n", __func__, *res == 0 ? "false" : "true");
	return 0;
}

static int decode_attr_symlink_support(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_SYMLINK_SUPPORT - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_SYMLINK_SUPPORT)) {
		READ_BUF(4);
		READ32(*res);
		bitmap[0] &= ~FATTR4_WORD0_SYMLINK_SUPPORT;
	}
	dprintk("%s: symlink support=%s\n", __func__, *res == 0 ? "false" : "true");
	return 0;
}

static int decode_attr_fsid(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs_fsid *fsid)
{
	__be32 *p;
	int ret = 0;

	fsid->major = 0;
	fsid->minor = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_FSID - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_FSID)) {
		READ_BUF(16);
		READ64(fsid->major);
		READ64(fsid->minor);
		bitmap[0] &= ~FATTR4_WORD0_FSID;
		ret = NFS_ATTR_FATTR_FSID;
	}
	dprintk("%s: fsid=(0x%Lx/0x%Lx)\n", __func__,
			(unsigned long long)fsid->major,
			(unsigned long long)fsid->minor);
	return ret;
}

static int decode_attr_lease_time(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;

	*res = 60;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_LEASE_TIME - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_LEASE_TIME)) {
		READ_BUF(4);
		READ32(*res);
		bitmap[0] &= ~FATTR4_WORD0_LEASE_TIME;
	}
	dprintk("%s: file size=%u\n", __func__, (unsigned int)*res);
	return 0;
}

static int decode_attr_aclsupport(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;

	*res = ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_ACLSUPPORT - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_ACLSUPPORT)) {
		READ_BUF(4);
		READ32(*res);
		bitmap[0] &= ~FATTR4_WORD0_ACLSUPPORT;
	}
	dprintk("%s: ACLs supported=%u\n", __func__, (unsigned int)*res);
	return 0;
}

static int decode_attr_fileid(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *fileid)
{
	__be32 *p;
	int ret = 0;

	*fileid = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_FILEID - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_FILEID)) {
		READ_BUF(8);
		READ64(*fileid);
		bitmap[0] &= ~FATTR4_WORD0_FILEID;
		ret = NFS_ATTR_FATTR_FILEID;
	}
	dprintk("%s: fileid=%Lu\n", __func__, (unsigned long long)*fileid);
	return ret;
}

static int decode_attr_mounted_on_fileid(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *fileid)
{
	__be32 *p;
	int ret = 0;

	*fileid = 0;
	if (unlikely(bitmap[1] & (FATTR4_WORD1_MOUNTED_ON_FILEID - 1U)))
		return -EIO;
	if (likely(bitmap[1] & FATTR4_WORD1_MOUNTED_ON_FILEID)) {
		READ_BUF(8);
		READ64(*fileid);
		bitmap[1] &= ~FATTR4_WORD1_MOUNTED_ON_FILEID;
		ret = NFS_ATTR_FATTR_FILEID;
	}
	dprintk("%s: fileid=%Lu\n", __func__, (unsigned long long)*fileid);
	return ret;
}

static int decode_attr_files_avail(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_AVAIL - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_FILES_AVAIL)) {
		READ_BUF(8);
		READ64(*res);
		bitmap[0] &= ~FATTR4_WORD0_FILES_AVAIL;
	}
	dprintk("%s: files avail=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}

static int decode_attr_files_free(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_FREE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_FILES_FREE)) {
		READ_BUF(8);
		READ64(*res);
		bitmap[0] &= ~FATTR4_WORD0_FILES_FREE;
	}
	dprintk("%s: files free=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}

static int decode_attr_files_total(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_FILES_TOTAL - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_FILES_TOTAL)) {
		READ_BUF(8);
		READ64(*res);
		bitmap[0] &= ~FATTR4_WORD0_FILES_TOTAL;
	}
	dprintk("%s: files total=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}

static int decode_pathname(struct xdr_stream *xdr, struct nfs4_pathname *path)
{
	u32 n;
	__be32 *p;
	int status = 0;

	READ_BUF(4);
	READ32(n);
	if (n == 0)
		goto root_path;
	dprintk("path ");
	path->ncomponents = 0;
	while (path->ncomponents < n) {
		struct nfs4_string *component = &path->components[path->ncomponents];
		status = decode_opaque_inline(xdr, &component->len, &component->data);
		if (unlikely(status != 0))
			goto out_eio;
		if (path->ncomponents != n)
			dprintk("/");
		dprintk("%s", component->data);
		if (path->ncomponents < NFS4_PATHNAME_MAXCOMPONENTS)
			path->ncomponents++;
		else {
			dprintk("cannot parse %d components in path\n", n);
			goto out_eio;
		}
	}
out:
	dprintk("\n");
	return status;
root_path:
/* a root pathname is sent as a zero component4 */
	path->ncomponents = 1;
	path->components[0].len=0;
	path->components[0].data=NULL;
	dprintk("path /\n");
	goto out;
out_eio:
	dprintk(" status %d", status);
	status = -EIO;
	goto out;
}

static int decode_attr_fs_locations(struct xdr_stream *xdr, uint32_t *bitmap, struct nfs4_fs_locations *res)
{
	int n;
	__be32 *p;
	int status = -EIO;

	if (unlikely(bitmap[0] & (FATTR4_WORD0_FS_LOCATIONS -1U)))
		goto out;
	status = 0;
	if (unlikely(!(bitmap[0] & FATTR4_WORD0_FS_LOCATIONS)))
		goto out;
	dprintk("%s: fsroot ", __func__);
	status = decode_pathname(xdr, &res->fs_path);
	if (unlikely(status != 0))
		goto out;
	READ_BUF(4);
	READ32(n);
	if (n <= 0)
		goto out_eio;
	res->nlocations = 0;
	while (res->nlocations < n) {
		u32 m;
		struct nfs4_fs_location *loc = &res->locations[res->nlocations];

		READ_BUF(4);
		READ32(m);

		loc->nservers = 0;
		dprintk("%s: servers ", __func__);
		while (loc->nservers < m) {
			struct nfs4_string *server = &loc->servers[loc->nservers];
			status = decode_opaque_inline(xdr, &server->len, &server->data);
			if (unlikely(status != 0))
				goto out_eio;
			dprintk("%s ", server->data);
			if (loc->nservers < NFS4_FS_LOCATION_MAXSERVERS)
				loc->nservers++;
			else {
				unsigned int i;
				dprintk("%s: using first %u of %u servers "
					"returned for location %u\n",
						__func__,
						NFS4_FS_LOCATION_MAXSERVERS,
						m, res->nlocations);
				for (i = loc->nservers; i < m; i++) {
					unsigned int len;
					char *data;
					status = decode_opaque_inline(xdr, &len, &data);
					if (unlikely(status != 0))
						goto out_eio;
				}
			}
		}
		status = decode_pathname(xdr, &loc->rootpath);
		if (unlikely(status != 0))
			goto out_eio;
		if (res->nlocations < NFS4_FS_LOCATIONS_MAXENTRIES)
			res->nlocations++;
	}
	if (res->nlocations != 0)
		status = NFS_ATTR_FATTR_V4_REFERRAL;
out:
	dprintk("%s: fs_locations done, error = %d\n", __func__, status);
	return status;
out_eio:
	status = -EIO;
	goto out;
}

static int decode_attr_maxfilesize(struct xdr_stream *xdr, uint32_t *bitmap, uint64_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 0;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXFILESIZE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXFILESIZE)) {
		READ_BUF(8);
		READ64(*res);
		bitmap[0] &= ~FATTR4_WORD0_MAXFILESIZE;
	}
	dprintk("%s: maxfilesize=%Lu\n", __func__, (unsigned long long)*res);
	return status;
}

static int decode_attr_maxlink(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *maxlink)
{
	__be32 *p;
	int status = 0;

	*maxlink = 1;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXLINK - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXLINK)) {
		READ_BUF(4);
		READ32(*maxlink);
		bitmap[0] &= ~FATTR4_WORD0_MAXLINK;
	}
	dprintk("%s: maxlink=%u\n", __func__, *maxlink);
	return status;
}

static int decode_attr_maxname(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *maxname)
{
	__be32 *p;
	int status = 0;

	*maxname = 1024;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXNAME - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXNAME)) {
		READ_BUF(4);
		READ32(*maxname);
		bitmap[0] &= ~FATTR4_WORD0_MAXNAME;
	}
	dprintk("%s: maxname=%u\n", __func__, *maxname);
	return status;
}

static int decode_attr_maxread(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 1024;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXREAD - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXREAD)) {
		uint64_t maxread;
		READ_BUF(8);
		READ64(maxread);
		if (maxread > 0x7FFFFFFF)
			maxread = 0x7FFFFFFF;
		*res = (uint32_t)maxread;
		bitmap[0] &= ~FATTR4_WORD0_MAXREAD;
	}
	dprintk("%s: maxread=%lu\n", __func__, (unsigned long)*res);
	return status;
}

static int decode_attr_maxwrite(struct xdr_stream *xdr, uint32_t *bitmap, uint32_t *res)
{
	__be32 *p;
	int status = 0;

	*res = 1024;
	if (unlikely(bitmap[0] & (FATTR4_WORD0_MAXWRITE - 1U)))
		return -EIO;
	if (likely(bitmap[0] & FATTR4_WORD0_MAXWRITE)) {
		uint64_t maxwrite;
		READ_BUF(8);
		READ64(maxwrite);
		if (maxwrite > 0x7FFFFFFF)
			maxwrite = 0x7FFFFFFF;
		*res = (uint32_t)maxwrite;
		bitmap[0] &= ~FATTR4_WORD0_MAXWRITE;
	}
	dprintk("%s: maxwrite=%lu\n", __func__, (unsigned long)*res);
	return status;
}

static int decode_attr_mode(struct xdr_stream *xdr, uint32_t *bitmap, umode_t *mode)
{
	uint32_t tmp;
	__be32 *p;
	int ret = 0;

	*mode = 0;
	if (unlikely(bitmap[1] & (FATTR4_WORD1_MODE - 1U)))
		return -EIO;
	if (likely(bitmap[1] & FATTR4_WORD1_MODE)) {
		READ_BUF(4);
		READ32(tmp);
		*mode = tmp & ~S_IFMT;
		bitmap[1] &= ~FATTR4_WORD1_MODE;
		ret = NFS_ATTR_FATTR_MODE;