This patch adds READ_PLUS support for both NFS4_CONTENT_DATA and
NFS4_CONTENT_HOLE segments. I keep things simple for now by only
returning a hole segment if it is the first segment found at the given
offset. Everything else, including other hole segments, will be encoded
as data.
Signed-off-by: Anna Schumaker <Anna.Schumaker@xxxxxxxxxx>
---
fs/nfsd/nfs4proc.c | 16 +++++++
fs/nfsd/nfs4xdr.c | 113 ++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 127 insertions(+), 2 deletions(-)
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 0cfd257ffdaf..1c5f2c3da55f 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -2180,6 +2180,16 @@ 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 xdr = 5;
+
+ return (op_encode_hdr_size + 2 + xdr + XDR_QUADLEN(rlen)) * sizeof(__be32);
+}
+
static inline u32 nfsd4_readdir_rsize(struct svc_rqst *rqstp, struct nfsd4_op *op)
{
u32 maxcount = 0, rlen = 0;
@@ -2701,6 +2711,12 @@ 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_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 bb487e5c022c..ec953efd24c2 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,
@@ -4273,7 +4273,116 @@ 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,
+ struct file *file)
+{
+ struct xdr_stream *xdr = &resp->xdr;
+ unsigned long maxcount;
+ __be32 *p, nfserr;
+
+ p = xdr_reserve_space(xdr, 4 + 8 + 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);
+
+ if (file->f_op->splice_read &&
+ test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
+ nfserr = nfsd4_encode_splice_read(resp, read, file, &maxcount);
+ else
+ nfserr = nfsd4_encode_readv(resp, read, file, &maxcount);
+
+ *p++ = cpu_to_be32(NFS4_CONTENT_DATA);
+ p = xdr_encode_hyper(p, read->rd_offset);
+ *p++ = cpu_to_be32(maxcount);
+
+ read->rd_offset += maxcount;
+ return nfserr;
+}
+
+static __be32
+nfsd4_encode_read_plus_hole(struct nfsd4_compoundres *resp, struct nfsd4_read *read,
+ unsigned long length)
+{
+ __be32 *p = xdr_reserve_space(&resp->xdr, 4 + 8 + 8);
+ if (!p)
+ return nfserr_resource;
+
+ length = min_t(unsigned long, read->rd_length, length);
+
+ *p++ = cpu_to_be32(NFS4_CONTENT_HOLE);
+ p = xdr_encode_hyper(p, read->rd_offset);
+ p = xdr_encode_hyper(p, length);
+
+ read->rd_offset += length;
+ read->rd_length -= length;
+ return nfs_ok;
+}
+static __be32
+nfsd4_encode_read_plus(struct nfsd4_compoundres *resp, __be32 nfserr,
+ struct nfsd4_read *read)
+{
+ struct xdr_stream *xdr = &resp->xdr;
+ struct file *file = read->rd_filp;
+ int starting_len = xdr->buf->len;
+ struct raparms *ra = NULL;
+ loff_t data_pos;
+ __be32 *p;
+ u32 eof, segments = 0;
+
+ if (nfserr)
+ goto out;
+
+ /* eof flag, segment count */
+ p = xdr_reserve_space(xdr, 4 + 4 );
+ if (!p) {
+ nfserr = nfserr_resource;
+ goto out;
+ }
+ xdr_commit_encode(xdr);
+
+ if (read->rd_tmp_file)
+ ra = nfsd_init_raparms(file);
+
+ data_pos = vfs_llseek(file, read->rd_offset, SEEK_DATA);
+ if (data_pos == -ENXIO)
+ data_pos = i_size_read(file_inode(file));
+
+ if (data_pos > read->rd_offset) {
+ nfserr = nfsd4_encode_read_plus_hole(resp, read,
+ data_pos - read->rd_offset);
+ if (nfserr)
+ goto out;
+ segments++;
+ }
+
+ if (read->rd_length > 0) {
+ nfserr = nfsd4_encode_read_plus_data(resp, read, file);
+ segments++;
+ }
+
+ eof = (read->rd_offset >= i_size_read(file_inode(file)));
+ *p++ = cpu_to_be32(eof);
+ *p++ = cpu_to_be32(segments);
+
+ if (ra)
+ nfsd_put_raparams(file, ra);
+
+ if (nfserr)
+ xdr_truncate_encode(xdr, starting_len);
+
+out:
+ if (file)
+ fput(file);
return nfserr;
}
@@ -4381,7 +4490,7 @@ 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,
--
2.20.1
