From patchwork Wed Sep 7 11:33:16 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeff Layton X-Patchwork-Id: 12968879 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 AB129C6FA90 for ; Wed, 7 Sep 2022 11:33:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230181AbiIGLdn (ORCPT ); Wed, 7 Sep 2022 07:33:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36990 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230089AbiIGLdd (ORCPT ); Wed, 7 Sep 2022 07:33:33 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 22679B6D01; Wed, 7 Sep 2022 04:33:32 -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 B654A6185F; Wed, 7 Sep 2022 11:33:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id F0801C4347C; Wed, 7 Sep 2022 11:33:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662550411; bh=UtpmRgctuu/Uj5QkJbhrsp/EEwNxyiqmQFCHXeh1350=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gEjTJB2eeaSYFBLsRymBFqIkjtbgN0EvVQZJxP0JbjBcr0cQYf1GTTQnoAquh1sPV XoLQKuHzKjXpxHuLB882sFfNpVGL7Eb7lsNd1X3d9vEfCv5ndSlM2Bwnmp43dpwmWe zDusx1LG8MRqghzMJk8hXwFkEP9c/f+1tazGGZuoyGkc/VbfbYXC8kElAG4TFTy/vx tD60GUQvEBofEb+zf/aLJigxZNqoa06xpNZ37zTkf15h3iWfFE51BHdTNMO+MqN+2d ud3aGQlz7Sz1LNbJxb+CMzML7D7VyIOQnuvJXQfo0Q3qskmq1C4werVKbMJS5PhbN2 8DBGmeCN2w9Ag== From: Jeff Layton To: tytso@mit.edu, adilger.kernel@dilger.ca, djwong@kernel.org, david@fromorbit.com, trondmy@hammerspace.com, neilb@suse.de, viro@zeniv.linux.org.uk, zohar@linux.ibm.com, xiubli@redhat.com, chuck.lever@oracle.com, lczerner@redhat.com, jack@suse.cz, bfields@fieldses.org, brauner@kernel.org, fweimer@redhat.com Cc: linux-api@vger.kernel.org, linux-btrfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, ceph-devel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-nfs@vger.kernel.org, linux-xfs@vger.kernel.org, Jeff Layton , David Howells , Frank Filz Subject: [PATCH v4 4/6] vfs: report an inode version in statx for IS_I_VERSION inodes Date: Wed, 7 Sep 2022 07:33:16 -0400 Message-Id: <20220907113318.21810-5-jlayton@kernel.org> X-Mailer: git-send-email 2.37.3 In-Reply-To: <20220907113318.21810-1-jlayton@kernel.org> References: <20220907113318.21810-1-jlayton@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: Jeff Layton The NFS server and IMA both rely heavily on the i_version counter, but it's largely invisible to userland, which makes it difficult to test its behavior. This value would also be of use to userland NFS servers, and other applications that want a reliable way to know whether there might have been an explicit change to an inode since they last checked. Claim one of the spare fields in struct statx to hold a 64-bit inode version attribute. This value must change with any explicit, observeable metadata or data change. Note that atime updates are excluded from this, unless it is due to an explicit change via utimes or similar mechanism. When statx requests this attribute on an IS_I_VERSION inode, do an inode_query_iversion and fill the result in the field. Also, update the test-statx.c program to display the inode version and the mountid. Cc: David Howells Cc: Frank Filz Signed-off-by: Jeff Layton --- fs/stat.c | 7 +++++++ include/linux/stat.h | 1 + include/uapi/linux/stat.h | 3 ++- samples/vfs/test-statx.c | 8 ++++++-- 4 files changed, 16 insertions(+), 3 deletions(-) diff --git a/fs/stat.c b/fs/stat.c index 9ced8860e0f3..d892909836aa 100644 --- a/fs/stat.c +++ b/fs/stat.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -118,6 +119,11 @@ int vfs_getattr_nosec(const struct path *path, struct kstat *stat, stat->attributes_mask |= (STATX_ATTR_AUTOMOUNT | STATX_ATTR_DAX); + if ((request_mask & STATX_INO_VERSION) && IS_I_VERSION(inode)) { + stat->result_mask |= STATX_INO_VERSION; + stat->ino_version = inode_query_iversion(inode); + } + mnt_userns = mnt_user_ns(path->mnt); if (inode->i_op->getattr) return inode->i_op->getattr(mnt_userns, path, stat, @@ -611,6 +617,7 @@ cp_statx(const struct kstat *stat, struct statx __user *buffer) tmp.stx_dev_major = MAJOR(stat->dev); tmp.stx_dev_minor = MINOR(stat->dev); tmp.stx_mnt_id = stat->mnt_id; + tmp.stx_ino_version = stat->ino_version; return copy_to_user(buffer, &tmp, sizeof(tmp)) ? -EFAULT : 0; } diff --git a/include/linux/stat.h b/include/linux/stat.h index 7df06931f25d..9cd77eb7bc1a 100644 --- a/include/linux/stat.h +++ b/include/linux/stat.h @@ -50,6 +50,7 @@ struct kstat { struct timespec64 btime; /* File creation time */ u64 blocks; u64 mnt_id; + u64 ino_version; }; #endif diff --git a/include/uapi/linux/stat.h b/include/uapi/linux/stat.h index 1500a0f58041..48d9307d7f31 100644 --- a/include/uapi/linux/stat.h +++ b/include/uapi/linux/stat.h @@ -124,7 +124,7 @@ struct statx { __u32 stx_dev_minor; /* 0x90 */ __u64 stx_mnt_id; - __u64 __spare2; + __u64 stx_ino_version; /* Inode change attribute */ /* 0xa0 */ __u64 __spare3[12]; /* Spare space for future expansion */ /* 0x100 */ @@ -152,6 +152,7 @@ struct statx { #define STATX_BASIC_STATS 0x000007ffU /* The stuff in the normal stat struct */ #define STATX_BTIME 0x00000800U /* Want/got stx_btime */ #define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */ +#define STATX_INO_VERSION 0x00002000U /* Want/got stx_change_attr */ #define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */ diff --git a/samples/vfs/test-statx.c b/samples/vfs/test-statx.c index 49c7a46cee07..23e68036fdfb 100644 --- a/samples/vfs/test-statx.c +++ b/samples/vfs/test-statx.c @@ -107,6 +107,8 @@ static void dump_statx(struct statx *stx) printf("Device: %-15s", buffer); if (stx->stx_mask & STATX_INO) printf(" Inode: %-11llu", (unsigned long long) stx->stx_ino); + if (stx->stx_mask & STATX_MNT_ID) + printf(" MountId: %llx", stx->stx_mnt_id); if (stx->stx_mask & STATX_NLINK) printf(" Links: %-5u", stx->stx_nlink); if (stx->stx_mask & STATX_TYPE) { @@ -145,7 +147,9 @@ static void dump_statx(struct statx *stx) if (stx->stx_mask & STATX_CTIME) print_time("Change: ", &stx->stx_ctime); if (stx->stx_mask & STATX_BTIME) - print_time(" Birth: ", &stx->stx_btime); + print_time("Birth: ", &stx->stx_btime); + if (stx->stx_mask & STATX_INO_VERSION) + printf("Inode Version: 0x%llx\n", stx->stx_ino_version); if (stx->stx_attributes_mask) { unsigned char bits, mbits; @@ -218,7 +222,7 @@ int main(int argc, char **argv) struct statx stx; int ret, raw = 0, atflag = AT_SYMLINK_NOFOLLOW; - unsigned int mask = STATX_BASIC_STATS | STATX_BTIME; + unsigned int mask = STATX_BASIC_STATS | STATX_BTIME | STATX_MNT_ID | STATX_INO_VERSION; for (argv++; *argv; argv++) { if (strcmp(*argv, "-F") == 0) {