NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment()

Refactor.

Now that the NFSv2 and NFSv3 XDR decoders have been converted to
use xdr_streams, the WRITE decoder functions can use
xdr_stream_subsegment() to extract the WRITE payload into its own
xdr_buf, just as the NFSv4 WRITE XDR decoder currently does.

That makes it possible to pass the first kvec, pages array + length,
page_base, and total payload length via a single function parameter.

The payload's page_base is not yet assigned or used, but will be in
subsequent patches.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
This commit is contained in:
Chuck Lever 2021-09-30 17:06:21 -04:00 committed by J. Bruce Fields
parent f49b68ddc9
commit dae9a6cab8
9 changed files with 15 additions and 33 deletions

View File

@ -201,8 +201,7 @@ nfsd3_proc_write(struct svc_rqst *rqstp)
fh_copy(&resp->fh, &argp->fh);
resp->committed = argp->stable;
nvecs = svc_fill_write_vector(rqstp, rqstp->rq_arg.pages,
&argp->first, cnt);
nvecs = svc_fill_write_vector(rqstp, &argp->payload);
if (!nvecs) {
resp->status = nfserr_io;
goto out;

View File

@ -621,9 +621,6 @@ nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
struct xdr_stream *xdr = &rqstp->rq_arg_stream;
struct nfsd3_writeargs *args = rqstp->rq_argp;
u32 max_blocksize = svc_max_payload(rqstp);
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
size_t remaining;
if (!svcxdr_decode_nfs_fh3(xdr, &args->fh))
return 0;
@ -641,17 +638,12 @@ nfs3svc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
/* request sanity */
if (args->count != args->len)
return 0;
remaining = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len;
remaining -= xdr_stream_pos(xdr);
if (remaining < xdr_align_size(args->len))
return 0;
if (args->count > max_blocksize) {
args->count = max_blocksize;
args->len = max_blocksize;
}
args->first.iov_base = xdr->p;
args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
if (!xdr_stream_subsegment(xdr, &args->payload, args->count))
return 0;
return 1;
}

View File

@ -1033,8 +1033,7 @@ nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
write->wr_how_written = write->wr_stable_how;
nvecs = svc_fill_write_vector(rqstp, write->wr_payload.pages,
write->wr_payload.head, write->wr_buflen);
nvecs = svc_fill_write_vector(rqstp, &write->wr_payload);
WARN_ON_ONCE(nvecs > ARRAY_SIZE(rqstp->rq_vec));
status = nfsd_vfs_write(rqstp, &cstate->current_fh, nf,

View File

@ -234,8 +234,7 @@ nfsd_proc_write(struct svc_rqst *rqstp)
SVCFH_fmt(&argp->fh),
argp->len, argp->offset);
nvecs = svc_fill_write_vector(rqstp, rqstp->rq_arg.pages,
&argp->first, cnt);
nvecs = svc_fill_write_vector(rqstp, &argp->payload);
if (!nvecs) {
resp->status = nfserr_io;
goto out;

View File

@ -325,10 +325,7 @@ nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
{
struct xdr_stream *xdr = &rqstp->rq_arg_stream;
struct nfsd_writeargs *args = rqstp->rq_argp;
struct kvec *head = rqstp->rq_arg.head;
struct kvec *tail = rqstp->rq_arg.tail;
u32 beginoffset, totalcount;
size_t remaining;
if (!svcxdr_decode_fhandle(xdr, &args->fh))
return 0;
@ -346,12 +343,8 @@ nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p)
return 0;
if (args->len > NFSSVC_MAXBLKSIZE_V2)
return 0;
remaining = head->iov_len + rqstp->rq_arg.page_len + tail->iov_len;
remaining -= xdr_stream_pos(xdr);
if (remaining < xdr_align_size(args->len))
if (!xdr_stream_subsegment(xdr, &args->payload, args->len))
return 0;
args->first.iov_base = xdr->p;
args->first.iov_len = head->iov_len - xdr_stream_pos(xdr);
return 1;
}

View File

@ -33,7 +33,7 @@ struct nfsd_writeargs {
svc_fh fh;
__u32 offset;
int len;
struct kvec first;
struct xdr_buf payload;
};
struct nfsd_createargs {

View File

@ -40,7 +40,7 @@ struct nfsd3_writeargs {
__u32 count;
int stable;
__u32 len;
struct kvec first;
struct xdr_buf payload;
};
struct nfsd3_createargs {

View File

@ -532,8 +532,7 @@ int svc_encode_result_payload(struct svc_rqst *rqstp,
unsigned int offset,
unsigned int length);
unsigned int svc_fill_write_vector(struct svc_rqst *rqstp,
struct page **pages,
struct kvec *first, size_t total);
struct xdr_buf *payload);
char *svc_fill_symlink_pathname(struct svc_rqst *rqstp,
struct kvec *first, void *p,
size_t total);

View File

@ -1676,16 +1676,17 @@ EXPORT_SYMBOL_GPL(svc_encode_result_payload);
/**
* svc_fill_write_vector - Construct data argument for VFS write call
* @rqstp: svc_rqst to operate on
* @pages: list of pages containing data payload
* @first: buffer containing first section of write payload
* @total: total number of bytes of write payload
* @payload: xdr_buf containing only the write data payload
*
* Fills in rqstp::rq_vec, and returns the number of elements.
*/
unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, struct page **pages,
struct kvec *first, size_t total)
unsigned int svc_fill_write_vector(struct svc_rqst *rqstp,
struct xdr_buf *payload)
{
struct page **pages = payload->pages;
struct kvec *first = payload->head;
struct kvec *vec = rqstp->rq_vec;
size_t total = payload->len;
unsigned int i;
/* Some types of transport can present the write payload