From patchwork Wed Nov 6 16:57:16 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chuck Lever X-Patchwork-Id: 13865190 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F41A284039 for ; Wed, 6 Nov 2024 16:57:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730912242; cv=none; b=oO3mtwJROjG/IBuctjktt5u2uc5OJt6rxHY5rx7yFEqScSGZi5NNBivjuSBo/mUOqaprhPj8xDVZdjW7wGL0V9UfKoOi2i1BE0kPk3XKX0FvKez096Utv2mDi9A6VqazuN6zi/Qpd8CZfdErCqD4u8Tlaa3bWcwocL5SKioX0PM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1730912242; c=relaxed/simple; bh=lb0eT0vICMnOrHkqYKJc+CV0/hIb9gUPhINRR84b1jA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Kc/Bg/LYRwSX0A0dENUyJ7DUvS38GQ90m634/BhsO5wB69keuyEil6llAaYpdN1P0Ekrwh1QOvu0diLpsZiWkjv6h0xzxNGnn+04dIgHj98sK+eclnRslaw+VEN0L3UREk8JYbTYU8k7OkIKKn9bI/k8QnWeANLtNaVYZEq6BtQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=BK6zQrv4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="BK6zQrv4" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DF1D6C4CECD; Wed, 6 Nov 2024 16:57:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1730912241; bh=lb0eT0vICMnOrHkqYKJc+CV0/hIb9gUPhINRR84b1jA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=BK6zQrv4xCcHAlrCP9BreE4GP611HcuvJarG8apYGOUL1o7kZEoj9Y9BATW535wEI pNd7o9HabP/1QBKBa/q5wDzTvvFzJRBe8tEVWW+rYD1ZTvHUvlZl9JBgUHgGl7NSYV FTUHfSO19WztqCVyue7PQyrX19Y9yRSeMXZzOIlrSaIdWbtCWmh/SsirpfuVk/wyjt kJUPQKXwiAwaVgEoZ5fMfrDm+kLjD0k/xcDHnnqlrEhqgQ7H9nBiknrVFnCe4oH6R3 UXlWZGg0S4VPgjEs9cvPyWrmPLm3uTzbIH2a62QLIR9XFBDwamCV3p4m4aWxUWXHdL qCACxZn71DskA== From: cel@kernel.org To: Neil Brown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey Cc: , Chuck Lever Subject: [RFC PATCH 2/2] NFSD: Add a "file_sync" export option Date: Wed, 6 Nov 2024 11:57:16 -0500 Message-ID: <20241106165716.109681-3-cel@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241106165716.109681-1-cel@kernel.org> References: <20241106165716.109681-1-cel@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Chuck Lever Introduce the kernel pieces for a "file_sync" export option. This option would make all NFS WRITE operations on one export a FILE_SYNC WRITE. There are two primary use cases for this new export option: 1. The exported file system is not backed by persistent storage. Thus a subsequent COMMIT will be a no-op. To prevent the client from wasting the extra round-trip on a COMMIT operation, convert all WRITEs to files on that export to FILE_SYNC. 2. The exported file system is backed by persistent storage that is faster than the mean network round trip with the client. Waiting for a separate COMMIT operation would cost more time than just committing the data during the WRITE operation. Either the underlying persistent storage is faster than most any network fabric (eg, NVMe); or the network connection to the client is very high latency (eg, a WAN link). Signed-off-by: Chuck Lever --- fs/nfsd/export.c | 1 + fs/nfsd/nfs4proc.c | 1 + fs/nfsd/vfs.c | 5 +++-- include/uapi/linux/nfsd/export.h | 3 ++- 4 files changed, 7 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/export.c b/fs/nfsd/export.c index c82d8e3e0d4f..11b5337dd0ea 100644 --- a/fs/nfsd/export.c +++ b/fs/nfsd/export.c @@ -1297,6 +1297,7 @@ static struct flags { { NFSEXP_V4ROOT, {"v4root", ""}}, { NFSEXP_PNFS, {"pnfs", ""}}, { NFSEXP_SECURITY_LABEL, {"security_label", ""}}, + { NFSEXP_FILE_SYNC, {"file_sync", ""}}, { 0, {"", ""}} }; diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c index 51bae11d5d23..7a4ded3ff7c2 100644 --- a/fs/nfsd/nfs4proc.c +++ b/fs/nfsd/nfs4proc.c @@ -1269,6 +1269,7 @@ nfsd4_clone(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, status = nfsd4_clone_file_range(rqstp, src, clone->cl_src_pos, dst, clone->cl_dst_pos, clone->cl_count, EX_ISSYNC(cstate->current_fh.fh_export)); + /* cel: check the "file_sync" export option as well */ nfsd_file_put(dst); nfsd_file_put(src); diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index cd00d95c997f..ffa6db6851bd 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1205,9 +1205,10 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct nfsd_file *nf, exp = fhp->fh_export; - if (!EX_ISSYNC(exp)) + if (exp->ex_flags & NFSEXP_FILE_SYNC) + *stable = NFS_FILE_SYNC; + else if (!EX_ISSYNC(exp)) *stable = NFS_UNSTABLE; - if (*stable && !fhp->fh_use_wgather) flags |= RWF_SYNC; diff --git a/include/uapi/linux/nfsd/export.h b/include/uapi/linux/nfsd/export.h index a73ca3703abb..45afec454a37 100644 --- a/include/uapi/linux/nfsd/export.h +++ b/include/uapi/linux/nfsd/export.h @@ -53,9 +53,10 @@ */ #define NFSEXP_V4ROOT 0x10000 #define NFSEXP_PNFS 0x20000 +#define NFSEXP_FILE_SYNC 0x40000 /* All flags that we claim to support. (Note we don't support NOACL.) */ -#define NFSEXP_ALLFLAGS 0x3FEFF +#define NFSEXP_ALLFLAGS 0x7FEFF /* The flags that may vary depending on security flavor: */ #define NFSEXP_SECINFO_FLAGS (NFSEXP_READONLY | NFSEXP_ROOTSQUASH \