From: Chuck Lever <chuck.lever@oracle.com>
Date: Thu, 30 Sep 2021 17:06:21 -0400
Subject: [PATCH] NFSD: Have legacy NFSD WRITE decoders use
xdr_stream_subsegment()
Git-commit: dae9a6cab8009e526570e7477ce858dcdfeb256e
Patch-mainline: v5.16
References: git-fixes
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>
Acked-by: NeilBrown <neilb@suse.com>
---
fs/nfsd/nfs3proc.c | 3 +--
fs/nfsd/nfs3xdr.c | 12 ++----------
fs/nfsd/nfs4proc.c | 3 +--
fs/nfsd/nfsproc.c | 3 +--
fs/nfsd/nfsxdr.c | 9 +--------
fs/nfsd/xdr.h | 2 +-
fs/nfsd/xdr3.h | 2 +-
include/linux/sunrpc/svc.h | 3 +--
net/sunrpc/svc.c | 11 ++++++-----
9 files changed, 15 insertions(+), 33 deletions(-)
--- a/fs/nfsd/nfs3proc.c
+++ b/fs/nfsd/nfs3proc.c
@@ -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;
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -621,9 +621,6 @@ nfs3svc_decode_writeargs(struct svc_rqst
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
/* 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;
}
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -1033,8 +1033,7 @@ nfsd4_write(struct svc_rqst *rqstp, stru
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,
--- a/fs/nfsd/nfsproc.c
+++ b/fs/nfsd/nfsproc.c
@@ -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;
--- a/fs/nfsd/nfsxdr.c
+++ b/fs/nfsd/nfsxdr.c
@@ -325,10 +325,7 @@ nfssvc_decode_writeargs(struct svc_rqst
{
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
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;
}
--- a/fs/nfsd/xdr.h
+++ b/fs/nfsd/xdr.h
@@ -33,7 +33,7 @@ struct nfsd_writeargs {
svc_fh fh;
__u32 offset;
int len;
- struct kvec first;
+ struct xdr_buf payload;
};
struct nfsd_createargs {
--- a/fs/nfsd/xdr3.h
+++ b/fs/nfsd/xdr3.h
@@ -40,7 +40,7 @@ struct nfsd3_writeargs {
__u32 count;
int stable;
__u32 len;
- struct kvec first;
+ struct xdr_buf payload;
};
struct nfsd3_createargs {
--- a/include/linux/sunrpc/svc.h
+++ b/include/linux/sunrpc/svc.h
@@ -528,8 +528,7 @@ int svc_encode_result_payload(struct
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);
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1664,16 +1664,17 @@ EXPORT_SYMBOL_GPL(svc_encode_result_payl
/**
* 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