Commit 528b8493 authored by Anna Schumaker's avatar Anna Schumaker Committed by J. Bruce Fields
Browse files

NFSD: Add READ_PLUS data support 



This patch adds READ_PLUS support for returning a single
NFS4_CONTENT_DATA segment to the client. This is basically the same as
the READ operation, only with the extra information about data segments.

Signed-off-by: default avatarAnna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
parent cc028a10

fs/nfsd/nfs4proc.c

+21 −0
Original line number Diff line number Diff line
@@ -2590,6 +2590,20 @@ static inline u32 nfsd4_read_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op) 
	return (op_encode_hdr_size + 2 + XDR_QUADLEN(rlen)) * sizeof(__be32);

}



static inline u32 nfsd4_read_plus_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)

{

	u32 maxcount = svc_max_payload(rqstp);

	u32 rlen = min(op->u.read.rd_length, maxcount);

	/*

	 * If we detect that the file changed during hole encoding, then we

	 * recover by encoding the remaining reply as data. This means we need

	 * to set aside enough room to encode two data segments.

	 */

	u32 seg_len = 2 * (1 + 2 + 1);



	return (op_encode_hdr_size + 2 + seg_len + XDR_QUADLEN(rlen)) * sizeof(__be32);

}



static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)

{

	u32 maxcount = 0, rlen = 0;
@@ -3162,6 +3176,13 @@ static const struct nfsd4_operation nfsd4_ops[] = { 
		.op_name = "OP_COPY",

		.op_rsize_bop = nfsd4_copy_rsize,

	},

	[OP_READ_PLUS] = {

		.op_func = nfsd4_read,

		.op_release = nfsd4_read_release,

		.op_name = "OP_READ_PLUS",

		.op_rsize_bop = nfsd4_read_plus_rsize,

		.op_get_currentstateid = nfsd4_get_readstateid,

	},

	[OP_SEEK] = {

		.op_func = nfsd4_seek,

		.op_name = "OP_SEEK",

fs/nfsd/nfs4xdr.c

+84 −3
Original line number Diff line number Diff line
@@ -2173,7 +2173,7 @@ static const nfsd4_dec nfsd4_dec_ops[] = { 
	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,

	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_offload_status,

	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_offload_status,

	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,

	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_read,

	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,

	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,

	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
@@ -2261,7 +2261,7 @@ nfsd4_decode_compound(struct nfsd4_compoundargs *argp) 
		 */

		cachethis |= nfsd4_cache_this_op(op);



		if (op->opnum == OP_READ) {

		if (op->opnum == OP_READ || op->opnum == OP_READ_PLUS) {

			readcount++;

			readbytes += nfsd4_max_reply(argp->rqstp, op);

		} else
@@ -4597,6 +4597,87 @@ nfsd4_encode_offload_status(struct nfsd4_compoundres *resp, __be32 nfserr, 
		return nfserr_resource;

	p = xdr_encode_hyper(p, os->count);

	*p++ = cpu_to_be32(0);

	return nfserr;

}



static __be32

nfsd4_encode_read_plus_data(struct nfsd4_compoundres *resp,

			    struct nfsd4_read *read,

			    unsigned long maxcount,  u32 *eof)

{

	struct xdr_stream *xdr = &resp->xdr;

	struct file *file = read->rd_nf->nf_file;

	int starting_len = xdr->buf->len;

	__be32 nfserr;

	__be32 *p, tmp;

	__be64 tmp64;



	maxcount = min_t(unsigned long, maxcount, (xdr->buf->buflen - xdr->buf->len));



	/* Content type, offset, byte count */

	p = xdr_reserve_space(xdr, 4 + 8 + 4);

	if (!p)

		return nfserr_resource;



	read->rd_vlen = xdr_reserve_space_vec(xdr, resp->rqstp->rq_vec, maxcount);

	if (read->rd_vlen < 0)

		return nfserr_resource;



	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,

			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount, eof);

	if (nfserr)

		return nfserr;



	tmp = htonl(NFS4_CONTENT_DATA);

	write_bytes_to_xdr_buf(xdr->buf, starting_len,      &tmp,   4);

	tmp64 = cpu_to_be64(read->rd_offset);

	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4,  &tmp64, 8);

	tmp = htonl(maxcount);

	write_bytes_to_xdr_buf(xdr->buf, starting_len + 12, &tmp,   4);

	return nfs_ok;

}



static __be32

nfsd4_encode_read_plus(struct nfsd4_compoundres *resp, __be32 nfserr,

		       struct nfsd4_read *read)

{

	unsigned long maxcount;

	struct xdr_stream *xdr = &resp->xdr;

	struct file *file;

	int starting_len = xdr->buf->len;

	int segments = 0;

	__be32 *p, tmp;

	u32 eof;



	if (nfserr)

		return nfserr;

	file = read->rd_nf->nf_file;



	/* eof flag, segment count */

	p = xdr_reserve_space(xdr, 4 + 4);

	if (!p)

		return nfserr_resource;

	xdr_commit_encode(xdr);



	maxcount = svc_max_payload(resp->rqstp);

	maxcount = min_t(unsigned long, maxcount,

			 (xdr->buf->buflen - xdr->buf->len));

	maxcount = min_t(unsigned long, maxcount, read->rd_length);



	eof = read->rd_offset >= i_size_read(file_inode(file));

	if (!eof) {

		nfserr = nfsd4_encode_read_plus_data(resp, read, maxcount, &eof);

		segments++;

	}



	if (nfserr)

		xdr_truncate_encode(xdr, starting_len);

	else {

		tmp = htonl(eof);

		write_bytes_to_xdr_buf(xdr->buf, starting_len,     &tmp, 4);

		tmp = htonl(segments);

		write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);

	}



	return nfserr;

}
@@ -4974,7 +5055,7 @@ static const nfsd4_enc nfsd4_enc_ops[] = { 
	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,

	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,

	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_offload_status,

	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,

	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_read_plus,

	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,

	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,

	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,