From patchwork Thu Aug 29 01:04:09 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Snitzer X-Patchwork-Id: 13782356 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 9149D146D6B; Thu, 29 Aug 2024 01:04:44 +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=1724893484; cv=none; b=nVzijzBjZGencCJLwBChijO4IdWCjIhbHhWc/VFj2hl4sNhKOB74jpONOCTkJJclD/eaB2NpsK5PvpnC19qBFRaK3JLdggzJh0aJVViL2u1sopxPikjU6f/QPJLQJDIzEajoBaNGENVDOFgtvcQ4lzavgfHzW7AJymhxHsPBk58= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724893484; c=relaxed/simple; bh=AoxM5yNAWr5nz7KLSiU7bwaL4xnyEb/TBFcmwe7lRkc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=SXtuHIu0s4GvsAdERVnAyGLBOekyZeDJa45ORZanDnVqVQSHc8UEPtPYjT8Qgnypz+yOWB9M6OKknVRfa9XaO3K+/IcKKeeRRalU94+EAUSX85JPQ7kLnCPICTAwpxW9bfevGdsFN7ApkehDJ5vLAKmMGIIaHSx8r2cZi18a9r8= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JojrRIr+; 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="JojrRIr+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3AC81C4AF0C; Thu, 29 Aug 2024 01:04:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724893484; bh=AoxM5yNAWr5nz7KLSiU7bwaL4xnyEb/TBFcmwe7lRkc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JojrRIr+4IaZykZgIdieRZlCnRs4PuEEJbxQjf2+47dj9NStLh1xfDNwoKHSIiPL5 VF1uasr1ip+J9dFolgtjf82dRd1BTh9rz9MyEnG0xDhFvhogYaCtg95+NKKleCCQNx nFfHK+OvHHjmNyaLAjShF5EwH+FKE4Wcc0QA2ZsKiMgm9/4/9uh4e48P+UDgdudmhg xcz1G37KlVbH/UftTLCTFL9NglZpi2zEsk0ysbk/0VZkwqY4VppLCeAUxAJop/9J7X x85cM9aKSsQ+OHJfdhLCUpI/MefgtsEEU0zl9u7sT7orykUOgmfP7LTalnkgOzGI+i 3wrEGJDMIEjTA== From: Mike Snitzer To: linux-nfs@vger.kernel.org Cc: Jeff Layton , Chuck Lever , Anna Schumaker , Trond Myklebust , NeilBrown , linux-fsdevel@vger.kernel.org Subject: [PATCH v14 14/25] nfs_common: add NFS LOCALIO auxiliary protocol enablement Date: Wed, 28 Aug 2024 21:04:09 -0400 Message-ID: <20240829010424.83693-15-snitzer@kernel.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240829010424.83693-1-snitzer@kernel.org> References: <20240829010424.83693-1-snitzer@kernel.org> Precedence: bulk X-Mailing-List: linux-nfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 fs/nfs_common/nfslocalio.c provides interfaces that enable an NFS client to generate a nonce (single-use UUID) and associated short-lived nfs_uuid_t struct, register it with nfs_common for subsequent lookup and verification by the NFS server and if matched the NFS server populates members in the nfs_uuid_t struct. nfs_common's nfs_uuids list is the basis for localio enablement, as such it has members that point to nfsd memory for direct use by the client (e.g. 'net' is the server's network namespace, through it the client can access nn->nfsd_serv with proper rcu read access). Signed-off-by: Mike Snitzer --- fs/nfs_common/Makefile | 3 ++ fs/nfs_common/nfslocalio.c | 74 ++++++++++++++++++++++++++++++++++++++ include/linux/nfslocalio.h | 31 ++++++++++++++++ 3 files changed, 108 insertions(+) create mode 100644 fs/nfs_common/nfslocalio.c create mode 100644 include/linux/nfslocalio.h diff --git a/fs/nfs_common/Makefile b/fs/nfs_common/Makefile index e58b01bb8dda..a5e54809701e 100644 --- a/fs/nfs_common/Makefile +++ b/fs/nfs_common/Makefile @@ -6,6 +6,9 @@ obj-$(CONFIG_NFS_ACL_SUPPORT) += nfs_acl.o nfs_acl-objs := nfsacl.o +obj-$(CONFIG_NFS_COMMON_LOCALIO_SUPPORT) += nfs_localio.o +nfs_localio-objs := nfslocalio.o + obj-$(CONFIG_GRACE_PERIOD) += grace.o obj-$(CONFIG_NFS_V4_2_SSC_HELPER) += nfs_ssc.o diff --git a/fs/nfs_common/nfslocalio.c b/fs/nfs_common/nfslocalio.c new file mode 100644 index 000000000000..1a35a4a6dbe0 --- /dev/null +++ b/fs/nfs_common/nfslocalio.c @@ -0,0 +1,74 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2024 Mike Snitzer + */ + +#include +#include +#include +#include + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("NFS localio protocol bypass support"); + +DEFINE_MUTEX(nfs_uuid_mutex); + +/* + * Global list of nfs_uuid_t instances, add/remove + * is protected by nfs_uuid_mutex. + * Reads are protected by RCU read lock (see below). + */ +LIST_HEAD(nfs_uuids); + +void nfs_uuid_begin(nfs_uuid_t *nfs_uuid) +{ + nfs_uuid->net = NULL; + nfs_uuid->dom = NULL; + uuid_gen(&nfs_uuid->uuid); + + mutex_lock(&nfs_uuid_mutex); + list_add_tail_rcu(&nfs_uuid->list, &nfs_uuids); + mutex_unlock(&nfs_uuid_mutex); +} +EXPORT_SYMBOL_GPL(nfs_uuid_begin); + +void nfs_uuid_end(nfs_uuid_t *nfs_uuid) +{ + mutex_lock(&nfs_uuid_mutex); + list_del_rcu(&nfs_uuid->list); + mutex_unlock(&nfs_uuid_mutex); +} +EXPORT_SYMBOL_GPL(nfs_uuid_end); + +/* Must be called with RCU read lock held. */ +static nfs_uuid_t * nfs_uuid_lookup(const uuid_t *uuid) +{ + nfs_uuid_t *nfs_uuid; + + list_for_each_entry_rcu(nfs_uuid, &nfs_uuids, list) + if (uuid_equal(&nfs_uuid->uuid, uuid)) + return nfs_uuid; + + return NULL; +} + +bool nfs_uuid_is_local(const uuid_t *uuid, struct net *net, struct auth_domain *dom) +{ + bool is_local = false; + nfs_uuid_t *nfs_uuid; + + rcu_read_lock(); + nfs_uuid = nfs_uuid_lookup(uuid); + if (nfs_uuid) { + nfs_uuid->net = maybe_get_net(net); + if (nfs_uuid->net) { + is_local = true; + kref_get(&dom->ref); + nfs_uuid->dom = dom; + } + } + rcu_read_unlock(); + + return is_local; +} +EXPORT_SYMBOL_GPL(nfs_uuid_is_local); diff --git a/include/linux/nfslocalio.h b/include/linux/nfslocalio.h new file mode 100644 index 000000000000..9735ae8d3e5e --- /dev/null +++ b/include/linux/nfslocalio.h @@ -0,0 +1,31 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2024 Mike Snitzer + */ +#ifndef __LINUX_NFSLOCALIO_H +#define __LINUX_NFSLOCALIO_H + +#include +#include +#include +#include +#include + +/* + * Useful to allow a client to negotiate if localio + * possible with its server. + * + * See Documentation/filesystems/nfs/localio.rst for more detail. + */ +typedef struct { + uuid_t uuid; + struct list_head list; + struct net *net; /* nfsd's network namespace */ + struct auth_domain *dom; /* auth_domain for localio */ +} nfs_uuid_t; + +void nfs_uuid_begin(nfs_uuid_t *); +void nfs_uuid_end(nfs_uuid_t *); +bool nfs_uuid_is_local(const uuid_t *, struct net *, struct auth_domain *); + +#endif /* __LINUX_NFSLOCALIO_H */