From 82078b9895bd46ce69b4a73e2da40e7e2202fdb5 Mon Sep 17 00:00:00 2001 From: Chuck Lever Date: Thu, 18 May 2023 13:45:36 -0400 Subject: [PATCH] NFSD: Ensure that xdr_write_pages updates rq_next_page All other NFSv[23] procedures manage to keep page_ptr and rq_next_page in lock step. Signed-off-by: Chuck Lever --- fs/nfsd/nfs3xdr.c | 11 +++++++---- fs/nfsd/nfsxdr.c | 11 +++++++---- include/linux/sunrpc/svc.h | 21 +++++++++++++++++++++ 3 files changed, 35 insertions(+), 8 deletions(-) diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index 3308dd671ef0..f32128955ec8 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -828,7 +828,8 @@ nfs3svc_encode_readlinkres(struct svc_rqst *rqstp, struct xdr_stream *xdr) return false; if (xdr_stream_encode_u32(xdr, resp->len) < 0) return false; - xdr_write_pages(xdr, resp->pages, 0, resp->len); + svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages, 0, + resp->len); if (svc_encode_result_payload(rqstp, head->iov_len, resp->len) < 0) return false; break; @@ -859,8 +860,9 @@ nfs3svc_encode_readres(struct svc_rqst *rqstp, struct xdr_stream *xdr) return false; if (xdr_stream_encode_u32(xdr, resp->count) < 0) return false; - xdr_write_pages(xdr, resp->pages, rqstp->rq_res.page_base, - resp->count); + svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages, + rqstp->rq_res.page_base, + resp->count); if (svc_encode_result_payload(rqstp, head->iov_len, resp->count) < 0) return false; break; @@ -961,7 +963,8 @@ nfs3svc_encode_readdirres(struct svc_rqst *rqstp, struct xdr_stream *xdr) return false; if (!svcxdr_encode_cookieverf3(xdr, resp->verf)) return false; - xdr_write_pages(xdr, dirlist->pages, 0, dirlist->len); + svcxdr_encode_opaque_pages(rqstp, xdr, dirlist->pages, 0, + dirlist->len); /* no more entries */ if (xdr_stream_encode_item_absent(xdr) < 0) return false; diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index caf6355b18fa..5777f40c7353 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -468,7 +468,8 @@ nfssvc_encode_readlinkres(struct svc_rqst *rqstp, struct xdr_stream *xdr) case nfs_ok: if (xdr_stream_encode_u32(xdr, resp->len) < 0) return false; - xdr_write_pages(xdr, &resp->page, 0, resp->len); + svcxdr_encode_opaque_pages(rqstp, xdr, &resp->page, 0, + resp->len); if (svc_encode_result_payload(rqstp, head->iov_len, resp->len) < 0) return false; break; @@ -491,8 +492,9 @@ nfssvc_encode_readres(struct svc_rqst *rqstp, struct xdr_stream *xdr) return false; if (xdr_stream_encode_u32(xdr, resp->count) < 0) return false; - xdr_write_pages(xdr, resp->pages, rqstp->rq_res.page_base, - resp->count); + svcxdr_encode_opaque_pages(rqstp, xdr, resp->pages, + rqstp->rq_res.page_base, + resp->count); if (svc_encode_result_payload(rqstp, head->iov_len, resp->count) < 0) return false; break; @@ -511,7 +513,8 @@ nfssvc_encode_readdirres(struct svc_rqst *rqstp, struct xdr_stream *xdr) return false; switch (resp->status) { case nfs_ok: - xdr_write_pages(xdr, dirlist->pages, 0, dirlist->len); + svcxdr_encode_opaque_pages(rqstp, xdr, dirlist->pages, 0, + dirlist->len); /* no more entries */ if (xdr_stream_encode_item_absent(xdr) < 0) return false; diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index 762d7231e574..3b10636c51a9 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -508,6 +508,27 @@ static inline void svcxdr_init_encode(struct svc_rqst *rqstp) xdr->rqst = NULL; } +/** + * svcxdr_encode_opaque_pages - Insert pages into an xdr_stream + * @xdr: xdr_stream to be updated + * @pages: array of pages to insert + * @base: starting offset of first data byte in @pages + * @len: number of data bytes in @pages to insert + * + * After the @pages are added, the tail iovec is instantiated pointing + * to end of the head buffer, and the stream is set up to encode + * subsequent items into the tail. + */ +static inline void svcxdr_encode_opaque_pages(struct svc_rqst *rqstp, + struct xdr_stream *xdr, + struct page **pages, + unsigned int base, + unsigned int len) +{ + xdr_write_pages(xdr, pages, base, len); + xdr->page_ptr = rqstp->rq_next_page - 1; +} + /** * svcxdr_set_auth_slack - * @rqstp: RPC transaction