From patchwork Fri Apr 28 19:52:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Anna Schumaker X-Patchwork-Id: 13226763 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F02EDC77B61 for ; Fri, 28 Apr 2023 19:52:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346458AbjD1TwT (ORCPT ); Fri, 28 Apr 2023 15:52:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229578AbjD1TwS (ORCPT ); Fri, 28 Apr 2023 15:52:18 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04ECB211E for ; Fri, 28 Apr 2023 12:52:18 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8A4D96151E for ; Fri, 28 Apr 2023 19:52:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9159AC433D2; Fri, 28 Apr 2023 19:52:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1682711536; bh=5RXRhTWACuxMk4kc+fmZGxwaAtqK4J1pVUUWkTgq4FU=; h=From:To:Cc:Subject:Date:From; b=LRLBmHYW4c7EP5QV05fHkDR/xQ3KIqfUSn3eLOZSmDqvONASekuhyjvv/0rZJH1Pt E6dSsSXolpT/UQLKzRKsKfeqiJO76nXN+BdiZafN9fHyQxq1Zpx7fhdGitk4CoxF8a uQyvgtRsCg8QCO5U1FpSIvVR7rEqusdZjxXlyAqPb/Kv7TPf4EFaalDIhpCYvVobmY /LFyn5TGv/9Pliwyup0yMxL2ijriKa0ADdk50/5sFora+MWNgK16xn6EPDZaCJHE0J OpM615Bm6awL+4+mATBXK3VDd/f7bnNSxEzKCcIK3MWgapJvqKv4zhqOAAW6FBmf5z MTzASBkmsW6CA== From: Anna Schumaker To: linux-nfs@vger.kernel.org, trond.myklebust@hammerspace.com Cc: anna@kernel.org Subject: [PATCH v2] NFSv4.2: Rework scratch handling for READ_PLUS Date: Fri, 28 Apr 2023 15:52:15 -0400 Message-Id: <20230428195215.234246-1-anna@kernel.org> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Anna Schumaker Instead of using a tiny, static scratch buffer, we should use a kmalloc()-ed buffer that is allocated when checking for read plus usage. This lets us use the buffer before decoding any part of the READ_PLUS operation instead of setting it right before segment decoding, meaning it should be a little more robust. Signed-off-by: Anna Schumaker --- fs/nfs/nfs42xdr.c | 4 ++-- fs/nfs/nfs4proc.c | 17 ++++++++++++----- include/linux/nfs_xdr.h | 1 + 3 files changed, 15 insertions(+), 7 deletions(-) diff --git a/fs/nfs/nfs42xdr.c b/fs/nfs/nfs42xdr.c index d80ee88ca996..a6df815a140c 100644 --- a/fs/nfs/nfs42xdr.c +++ b/fs/nfs/nfs42xdr.c @@ -1122,7 +1122,6 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res) uint32_t segments; struct read_plus_segment *segs; int status, i; - char scratch_buf[16]; __be32 *p; status = decode_op_hdr(xdr, OP_READ_PLUS); @@ -1143,7 +1142,6 @@ static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res) if (!segs) return -ENOMEM; - xdr_set_scratch_buffer(xdr, &scratch_buf, sizeof(scratch_buf)); status = -EIO; for (i = 0; i < segments; i++) { status = decode_read_plus_segment(xdr, &segs[i]); @@ -1348,6 +1346,8 @@ static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp, struct compound_hdr hdr; int status; + xdr_set_scratch_buffer(xdr, res->scratch, sizeof(res->scratch)); + status = decode_compound_hdr(xdr, &hdr); if (status) goto out; diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 5607b1e2b821..18f25ff4bff7 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -5439,6 +5439,8 @@ static bool nfs4_read_plus_not_supported(struct rpc_task *task, static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr) { + if (hdr->res.scratch) + kfree(hdr->res.scratch); if (!nfs4_sequence_done(task, &hdr->res.seq_res)) return -EAGAIN; if (nfs4_read_stateid_changed(task, &hdr->args)) @@ -5452,17 +5454,22 @@ static int nfs4_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr) } #if defined CONFIG_NFS_V4_2 && defined CONFIG_NFS_V4_2_READ_PLUS -static void nfs42_read_plus_support(struct nfs_pgio_header *hdr, +static bool nfs42_read_plus_support(struct nfs_pgio_header *hdr, struct rpc_message *msg) { /* Note: We don't use READ_PLUS with pNFS yet */ - if (nfs_server_capable(hdr->inode, NFS_CAP_READ_PLUS) && !hdr->ds_clp) + if (nfs_server_capable(hdr->inode, NFS_CAP_READ_PLUS) && !hdr->ds_clp) { msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ_PLUS]; + hdr->res.scratch = kmalloc(32, GFP_KERNEL); + return hdr->res.scratch != NULL; + } + return false; } #else -static void nfs42_read_plus_support(struct nfs_pgio_header *hdr, +static bool nfs42_read_plus_support(struct nfs_pgio_header *hdr, struct rpc_message *msg) { + return false; } #endif /* CONFIG_NFS_V4_2 */ @@ -5472,8 +5479,8 @@ static void nfs4_proc_read_setup(struct nfs_pgio_header *hdr, hdr->timestamp = jiffies; if (!hdr->pgio_done_cb) hdr->pgio_done_cb = nfs4_read_done_cb; - msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ]; - nfs42_read_plus_support(hdr, msg); + if (!nfs42_read_plus_support(hdr, msg)) + msg->rpc_proc = &nfs4_procedures[NFSPROC4_CLNT_READ]; nfs4_init_sequence(&hdr->args.seq_args, &hdr->res.seq_res, 0, 0); } diff --git a/include/linux/nfs_xdr.h b/include/linux/nfs_xdr.h index e86cf6642d21..2fd973d188c4 100644 --- a/include/linux/nfs_xdr.h +++ b/include/linux/nfs_xdr.h @@ -670,6 +670,7 @@ struct nfs_pgio_res { struct { unsigned int replen; /* used by read */ int eof; /* used by read */ + void * scratch; /* used by read */ }; struct { struct nfs_writeverf * verf; /* used by write */