This is a note to let you know that I've just added the patch titled NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: nfsd-have-legacy-nfsd-write-decoders-use-xdr_stream_.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit ecf1763d5630412d2835c650af53b4b67f70979d Author: Chuck Lever <chuck.lever@xxxxxxxxxx> Date: Thu Sep 30 17:06:21 2021 -0400 NFSD: Have legacy NFSD WRITE decoders use xdr_stream_subsegment() [ Upstream commit dae9a6cab8009e526570e7477ce858dcdfeb256e ] 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@xxxxxxxxxx> Signed-off-by: J. Bruce Fields <bfields@xxxxxxxxxx> [ cel: adjusted to apply to v5.10.y ] Signed-off-by: Chuck Lever <chuck.lever@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index be1ed33e424e0..5abb5c8e2cd21 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -206,8 +206,7 @@ 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; diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c index 3d37923afb06c..267e56f218af7 100644 --- a/fs/nfsd/nfs3xdr.c +++ b/fs/nfsd/nfs3xdr.c @@ -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; } diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index ebb6d8471e8d7..d2ee1ba7ddc65 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1034,8 +1034,7 @@ 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, diff --git a/fs/nfsd/nfsproc.c b/fs/nfsd/nfsproc.c index 78bdfdc253fd3..5a84aed17e705 100644 --- 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; diff --git a/fs/nfsd/nfsxdr.c b/fs/nfsd/nfsxdr.c index 082449c7d0dbf..ddcc18adfeb1a 100644 --- a/fs/nfsd/nfsxdr.c +++ b/fs/nfsd/nfsxdr.c @@ -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; } diff --git a/fs/nfsd/xdr.h b/fs/nfsd/xdr.h index c67ad02b9a028..863a35f24910a 100644 --- a/fs/nfsd/xdr.h +++ b/fs/nfsd/xdr.h @@ -33,7 +33,7 @@ struct nfsd_writeargs { svc_fh fh; __u32 offset; __u32 len; - struct kvec first; + struct xdr_buf payload; }; struct nfsd_createargs { diff --git a/fs/nfsd/xdr3.h b/fs/nfsd/xdr3.h index 933008382bbeb..712c117300cb7 100644 --- 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 { diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index dd3daadbc0e5c..b0986e969c2f4 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -531,8 +531,7 @@ 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); diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 0d3c3ca2830a8..54f66f66beb59 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -1654,16 +1654,17 @@ 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