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: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Anna Schumaker 2020-09-28 13:08:58 -04:00 committed by J. Bruce Fields
parent cc028a10a4
commit 528b84934e
2 changed files with 105 additions and 3 deletions

View File

@ -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",

View File

@ -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,