From: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
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: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
---
fs/nfsd/nfs4proc.c | 17 +++++++++
fs/nfsd/nfs4xdr.c | 90 ++++++++++++++++++++++++++++++++++++++++++----
2 files changed, 101 insertions(+), 6 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 4798667af647..3c11ca9bd5d7 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2179,6 +2179,16 @@ 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);
+ /* enough extra xdr space for encoding either a hole or data segment. */
+ u32 segments = 1 + 2 + 2;
+
+ return (op_encode_hdr_size + 2 + segments + XDR_QUADLEN(rlen)) * sizeof(__be32);
+}
+
static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
{
u32 maxcount = 0, rlen = 0;
@@ -2700,6 +2710,13 @@ 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",
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 812e82097879..014e05365c17 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1882,7 +1882,7 @@ 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,
@@ -3589,10 +3589,11 @@ nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
if (nfserr)
xdr_truncate_encode(xdr, starting_len);
-
- read->rd_length = maxcount;
- *p++ = htonl(eof);
- *p++ = htonl(maxcount);
+ else {
+ read->rd_length = maxcount;
+ *p++ = htonl(eof);
+ *p++ = htonl(maxcount);
+ }
return nfserr;
}
@@ -4264,6 +4265,83 @@ 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;
+ __be32 nfserr;
+ __be32 *p;
+
+ /* Content type, offset, byte count */
+ p = xdr_reserve_space(xdr, 4 + 8 + 4);
+ if (!p)
+ return nfserr_resource;
+ xdr_commit_encode(xdr);
+
+ if (file->f_op->splice_read &&
+ test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
+ nfserr = nfsd4_encode_splice_read(resp, read, file, &maxcount, eof);
+ else
+ nfserr = nfsd4_encode_readv(resp, read, file, &maxcount, eof);
+
+ if (nfserr)
+ return nfserr;
+
+ *p++ = htonl(NFS4_CONTENT_DATA);
+ p = xdr_encode_hyper(p, read->rd_offset);
+ *p++ = htonl(maxcount);
+
+ read->rd_offset += maxcount;
+ read->rd_length = (maxcount > 0) ? read->rd_length - maxcount : 0;
+ return nfserr;
+}
+
+static __be32
+nfsd4_encode_read_plus(struct nfsd4_compoundres *resp, __be32 nfserr,
+ struct nfsd4_read *read)
+{
+ unsigned long maxcount;
+ u32 eof;
+ struct xdr_stream *xdr = &resp->xdr;
+ struct file *file;
+ int starting_len = xdr->buf->len;
+ __be32 *p;
+
+ if (nfserr)
+ return nfserr;
+ file = read->rd_nf->nf_file;
+
+ /* eof flag, segment count */
+ p = xdr_reserve_space(xdr, 4 + 4);
+ if (!p) {
+ WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
+ return nfserr_resource;
+ }
+ if (resp->xdr.buf->page_len &&
+ test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
+ WARN_ON_ONCE(1);
+ 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);
+
+ nfserr = nfsd4_encode_read_plus_data(resp, read, maxcount, &eof);
+ if (nfserr)
+ xdr_truncate_encode(xdr, starting_len);
+ else {
+ *p++ = htonl(eof);
+ *p++ = htonl(1);
+ }
return nfserr;
}
@@ -4372,7 +4450,7 @@ 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,
--
2.24.1
