nfs3xdr.c

Linux Kernel 2.6.9 for OMAP1710

	pglen = rcvbuf->page_len;
	recvd = rcvbuf->len - hdrlen;
	if (pglen > recvd)
		pglen = recvd;
	page = rcvbuf->pages;
	kaddr = p = (u32 *)kmap_atomic(*page, KM_USER0);
	end = (u32 *)((char *)p + pglen);
	entry = p;
	for (nr = 0; *p++; nr++) {
		if (p + 3 > end)
			goto short_pkt;
		p += 2;				/* inode # */
		len = ntohl(*p++);		/* string length */
		p += XDR_QUADLEN(len) + 2;	/* name + cookie */
		if (len > NFS3_MAXNAMLEN) {
			printk(KERN_WARNING "NFS: giant filename in readdir (len %x)!\n",
						len);
			goto err_unmap;
		}

		if (res->plus) {
			/* post_op_attr */
			if (p + 2 > end)
				goto short_pkt;
			if (*p++) {
				p += 21;
				if (p + 1 > end)
					goto short_pkt;
			}
			/* post_op_fh3 */
			if (*p++) {
				if (p + 1 > end)
					goto short_pkt;
				len = ntohl(*p++);
				if (len > NFS3_FHSIZE) {
					printk(KERN_WARNING "NFS: giant filehandle in "
						"readdir (len %x)!\n", len);
					goto err_unmap;
				}
				p += XDR_QUADLEN(len);
			}
		}

		if (p + 2 > end)
			goto short_pkt;
		entry = p;
	}
	if (!nr && (entry[0] != 0 || entry[1] == 0))
		goto short_pkt;
 out:
	kunmap_atomic(kaddr, KM_USER0);
	return nr;
 short_pkt:
	entry[0] = entry[1] = 0;
	/* truncate listing ? */
	if (!nr) {
		printk(KERN_NOTICE "NFS: readdir reply truncated!\n");
		entry[1] = 1;
	}
	goto out;
err_unmap:
	nr = -errno_NFSERR_IO;
	goto out;
}

u32 *
nfs3_decode_dirent(u32 *p, struct nfs_entry *entry, int plus)
{
	struct nfs_entry old = *entry;

	if (!*p++) {
		if (!*p)
			return ERR_PTR(-EAGAIN);
		entry->eof = 1;
		return ERR_PTR(-EBADCOOKIE);
	}

	p = xdr_decode_hyper(p, &entry->ino);
	entry->len  = ntohl(*p++);
	entry->name = (const char *) p;
	p += XDR_QUADLEN(entry->len);
	entry->prev_cookie = entry->cookie;
	p = xdr_decode_hyper(p, &entry->cookie);

	if (plus) {
		entry->fattr->valid = 0;
		p = xdr_decode_post_op_attr(p, entry->fattr);
		/* In fact, a post_op_fh3: */
		if (*p++) {
			p = xdr_decode_fhandle(p, entry->fh);
			/* Ugh -- server reply was truncated */
			if (p == NULL) {
				dprintk("NFS: FH truncated\n");
				*entry = old;
				return ERR_PTR(-EAGAIN);
			}
		} else
			memset((u8*)(entry->fh), 0, sizeof(*entry->fh));
	}

	entry->eof = !p[0] && p[1];
	return p;
}

/*
 * Encode COMMIT arguments
 */
static int
nfs3_xdr_commitargs(struct rpc_rqst *req, u32 *p, struct nfs_writeargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_hyper(p, args->offset);
	*p++ = htonl(args->count);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * NFS XDR decode functions
 */

/*
 * Decode attrstat reply.
 */
static int
nfs3_xdr_attrstat(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	int	status;

	if ((status = ntohl(*p++)))
		return -nfs_stat_to_errno(status);
	xdr_decode_fattr(p, fattr);
	return 0;
}

/*
 * Decode status+wcc_data reply
 * SATTR, REMOVE, RMDIR
 */
static int
nfs3_xdr_wccstat(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	int	status;

	if ((status = ntohl(*p++)))
		status = -nfs_stat_to_errno(status);
	xdr_decode_wcc_data(p, fattr);
	return status;
}

/*
 * Decode LOOKUP reply
 */
static int
nfs3_xdr_lookupres(struct rpc_rqst *req, u32 *p, struct nfs3_diropres *res)
{
	int	status;

	if ((status = ntohl(*p++))) {
		status = -nfs_stat_to_errno(status);
	} else {
		if (!(p = xdr_decode_fhandle(p, res->fh)))
			return -errno_NFSERR_IO;
		p = xdr_decode_post_op_attr(p, res->fattr);
	}
	xdr_decode_post_op_attr(p, res->dir_attr);
	return status;
}

/*
 * Decode ACCESS reply
 */
static int
nfs3_xdr_accessres(struct rpc_rqst *req, u32 *p, struct nfs3_accessres *res)
{
	int	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status)
		return -nfs_stat_to_errno(status);
	res->access = ntohl(*p++);
	return 0;
}

static int
nfs3_xdr_readlinkargs(struct rpc_rqst *req, u32 *p, struct nfs3_readlinkargs *args)
{
	struct rpc_auth *auth = req->rq_task->tk_auth;
	unsigned int replen;

	p = xdr_encode_fhandle(p, args->fh);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	/* Inline the page array */
	replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS3_readlinkres_sz) << 2;
	xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, args->pglen);
	return 0;
}

/*
 * Decode READLINK reply
 */
static int
nfs3_xdr_readlinkres(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
	struct kvec *iov = rcvbuf->head;
	int hdrlen, len, recvd;
	char	*kaddr;
	int	status;

	status = ntohl(*p++);
	p = xdr_decode_post_op_attr(p, fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	/* Convert length of symlink */
	len = ntohl(*p++);
	if (len >= rcvbuf->page_len || len <= 0) {
		dprintk(KERN_WARNING "nfs: server returned giant symlink!\n");
		return -ENAMETOOLONG;
	}

	hdrlen = (u8 *) p - (u8 *) iov->iov_base;
	if (iov->iov_len < hdrlen) {
		printk(KERN_WARNING "NFS: READLINK reply header overflowed:"
				"length %d > %Zu\n", hdrlen, iov->iov_len);
		return -errno_NFSERR_IO;
	} else if (iov->iov_len != hdrlen) {
		dprintk("NFS: READLINK header is short. iovec will be shifted.\n");
		xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
	}
	recvd = req->rq_rcv_buf.len - hdrlen;
	if (recvd < len) {
		printk(KERN_WARNING "NFS: server cheating in readlink reply: "
				"count %u > recvd %u\n", len, recvd);
		return -EIO;
	}

	/* NULL terminate the string we got */
	kaddr = (char*)kmap_atomic(rcvbuf->pages[0], KM_USER0);
	kaddr[len+rcvbuf->page_base] = '\0';
	kunmap_atomic(kaddr, KM_USER0);
	return 0;
}

/*
 * Decode READ reply
 */
static int
nfs3_xdr_readres(struct rpc_rqst *req, u32 *p, struct nfs_readres *res)
{
	struct kvec *iov = req->rq_rcv_buf.head;
	int	status, count, ocount, recvd, hdrlen;

	status = ntohl(*p++);
	p = xdr_decode_post_op_attr(p, res->fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	/* Decode reply could and EOF flag. NFSv3 is somewhat redundant
	 * in that it puts the count both in the res struct and in the
	 * opaque data count. */
	count    = ntohl(*p++);
	res->eof = ntohl(*p++);
	ocount   = ntohl(*p++);

	if (ocount != count) {
		printk(KERN_WARNING "NFS: READ count doesn't match RPC opaque count.\n");
		return -errno_NFSERR_IO;
	}

	hdrlen = (u8 *) p - (u8 *) iov->iov_base;
	if (iov->iov_len < hdrlen) {
		printk(KERN_WARNING "NFS: READ reply header overflowed:"
				"length %d > %Zu\n", hdrlen, iov->iov_len);
       		return -errno_NFSERR_IO;
	} else if (iov->iov_len != hdrlen) {
		dprintk("NFS: READ header is short. iovec will be shifted.\n");
		xdr_shift_buf(&req->rq_rcv_buf, iov->iov_len - hdrlen);
	}

	recvd = req->rq_rcv_buf.len - hdrlen;
	if (count > recvd) {
		printk(KERN_WARNING "NFS: server cheating in read reply: "
			"count %d > recvd %d\n", count, recvd);
		count = recvd;
		res->eof = 0;
	}

	if (count < res->count)
		res->count = count;

	return count;
}

/*
 * Decode WRITE response
 */
static int
nfs3_xdr_writeres(struct rpc_rqst *req, u32 *p, struct nfs_writeres *res)
{
	int	status;

	status = ntohl(*p++);
	p = xdr_decode_wcc_data(p, res->fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->count = ntohl(*p++);
	res->verf->committed = (enum nfs3_stable_how)ntohl(*p++);
	res->verf->verifier[0] = *p++;
	res->verf->verifier[1] = *p++;

	return res->count;
}

/*
 * Decode a CREATE response
 */
static int
nfs3_xdr_createres(struct rpc_rqst *req, u32 *p, struct nfs3_diropres *res)
{
	int	status;

	status = ntohl(*p++);
	if (status == 0) {
		if (*p++) {
			if (!(p = xdr_decode_fhandle(p, res->fh)))
				return -errno_NFSERR_IO;
			p = xdr_decode_post_op_attr(p, res->fattr);
		} else {
			memset(res->fh, 0, sizeof(*res->fh));
			/* Do decode post_op_attr but set it to NULL */
			p = xdr_decode_post_op_attr(p, res->fattr);
			res->fattr->valid = 0;
		}
	} else {
		status = -nfs_stat_to_errno(status);
	}
	p = xdr_decode_wcc_data(p, res->dir_attr);
	return status;
}

/*
 * Decode RENAME reply
 */
static int
nfs3_xdr_renameres(struct rpc_rqst *req, u32 *p, struct nfs3_renameres *res)
{
	int	status;

	if ((status = ntohl(*p++)) != 0)
		status = -nfs_stat_to_errno(status);
	p = xdr_decode_wcc_data(p, res->fromattr);
	p = xdr_decode_wcc_data(p, res->toattr);
	return status;
}

/*
 * Decode LINK reply
 */
static int
nfs3_xdr_linkres(struct rpc_rqst *req, u32 *p, struct nfs3_linkres *res)
{
	int	status;

	if ((status = ntohl(*p++)) != 0)
		status = -nfs_stat_to_errno(status);
	p = xdr_decode_post_op_attr(p, res->fattr);
	p = xdr_decode_wcc_data(p, res->dir_attr);
	return status;
}

/*
 * Decode FSSTAT reply
 */
static int
nfs3_xdr_fsstatres(struct rpc_rqst *req, u32 *p, struct nfs_fsstat *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	p = xdr_decode_hyper(p, &res->tbytes);
	p = xdr_decode_hyper(p, &res->fbytes);
	p = xdr_decode_hyper(p, &res->abytes);
	p = xdr_decode_hyper(p, &res->tfiles);
	p = xdr_decode_hyper(p, &res->ffiles);
	p = xdr_decode_hyper(p, &res->afiles);

	/* ignore invarsec */
	return 0;
}

/*
 * Decode FSINFO reply
 */
static int
nfs3_xdr_fsinfores(struct rpc_rqst *req, u32 *p, struct nfs_fsinfo *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->rtmax  = ntohl(*p++);
	res->rtpref = ntohl(*p++);
	res->rtmult = ntohl(*p++);
	res->wtmax  = ntohl(*p++);
	res->wtpref = ntohl(*p++);
	res->wtmult = ntohl(*p++);
	res->dtpref = ntohl(*p++);
	p = xdr_decode_hyper(p, &res->maxfilesize);

	/* ignore time_delta and properties */
	res->lease_time = 0;
	return 0;
}

/*
 * Decode PATHCONF reply
 */
static int
nfs3_xdr_pathconfres(struct rpc_rqst *req, u32 *p, struct nfs_pathconf *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);
	res->max_link = ntohl(*p++);
	res->max_namelen = ntohl(*p++);

	/* ignore remaining fields */
	return 0;
}

/*
 * Decode COMMIT reply
 */
static int
nfs3_xdr_commitres(struct rpc_rqst *req, u32 *p, struct nfs_writeres *res)
{
	int		status;

	status = ntohl(*p++);
	p = xdr_decode_wcc_data(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->verf->verifier[0] = *p++;
	res->verf->verifier[1] = *p++;
	return 0;
}

#ifndef MAX
# define MAX(a, b)	(((a) > (b))? (a) : (b))
#endif

#define PROC(proc, argtype, restype, timer)				\
[NFS3PROC_##proc] = {							\
	.p_proc      = NFS3PROC_##proc,					\
	.p_encode    = (kxdrproc_t) nfs3_xdr_##argtype,			\
	.p_decode    = (kxdrproc_t) nfs3_xdr_##restype,			\
	.p_bufsiz    = MAX(NFS3_##argtype##_sz,NFS3_##restype##_sz) << 2,	\
	.p_timer     = timer						\
	}

struct rpc_procinfo	nfs3_procedures[] = {
  PROC(GETATTR,		fhandle,	attrstat, 1),
  PROC(SETATTR, 	sattrargs,	wccstat, 0),
  PROC(LOOKUP,		diropargs,	lookupres, 2),
  PROC(ACCESS,		accessargs,	accessres, 1),
  PROC(READLINK,	readlinkargs,	readlinkres, 3),
  PROC(READ,		readargs,	readres, 3),
  PROC(WRITE,		writeargs,	writeres, 4),
  PROC(CREATE,		createargs,	createres, 0),
  PROC(MKDIR,		mkdirargs,	createres, 0),
  PROC(SYMLINK,		symlinkargs,	createres, 0),
  PROC(MKNOD,		mknodargs,	createres, 0),
  PROC(REMOVE,		diropargs,	wccstat, 0),
  PROC(RMDIR,		diropargs,	wccstat, 0),
  PROC(RENAME,		renameargs,	renameres, 0),
  PROC(LINK,		linkargs,	linkres, 0),
  PROC(READDIR,		readdirargs,	readdirres, 3),
  PROC(READDIRPLUS,	readdirargs,	readdirres, 3),
  PROC(FSSTAT,		fhandle,	fsstatres, 0),
  PROC(FSINFO,  	fhandle,	fsinfores, 0),
  PROC(PATHCONF,	fhandle,	pathconfres, 0),
  PROC(COMMIT,		commitargs,	commitres, 5),
};

struct rpc_version		nfs_version3 = {
	.number			= 3,
	.nrprocs		= sizeof(nfs3_procedures)/sizeof(nfs3_procedures[0]),
	.procs			= nfs3_procedures
};