From 76e589013fec672c3587d6314f2d1f0aeddc26d9 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 11 Sep 2023 08:42:34 -0700 Subject: [PATCH 1/2] xfs: allow inode inactivation during a ro mount log recovery In the next patch, we're going to prohibit log recovery if the primary superblock contains an unrecognized rocompat feature bit even on readonly mounts. This requires removing all the code in the log mounting process that temporarily disables the readonly state. Unfortunately, inode inactivation disables itself on readonly mounts. Clearing the iunlinked lists after log recovery needs inactivation to run to free the unreferenced inodes, which (AFAICT) is the only reason why log mounting plays games with the readonly state in the first place. Therefore, change the inactivation predicates to allow inactivation during log recovery of a readonly mount. Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner --- fs/xfs/xfs_inode.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 360fe83a334f..f7f8292347ab 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -1642,8 +1642,11 @@ xfs_inode_needs_inactive( if (VFS_I(ip)->i_mode == 0) return false; - /* If this is a read-only mount, don't do this (would generate I/O) */ - if (xfs_is_readonly(mp)) + /* + * If this is a read-only mount, don't do this (would generate I/O) + * unless we're in log recovery and cleaning the iunlinked list. + */ + if (xfs_is_readonly(mp) && !xlog_recovery_needed(mp->m_log)) return false; /* If the log isn't running, push inodes straight to reclaim. */ @@ -1703,8 +1706,11 @@ xfs_inactive( mp = ip->i_mount; ASSERT(!xfs_iflags_test(ip, XFS_IRECOVERY)); - /* If this is a read-only mount, don't do this (would generate I/O) */ - if (xfs_is_readonly(mp)) + /* + * If this is a read-only mount, don't do this (would generate I/O) + * unless we're in log recovery and cleaning the iunlinked list. + */ + if (xfs_is_readonly(mp) && !xlog_recovery_needed(mp->m_log)) goto out; /* Metadata inodes require explicit resource cleanup. */ From 74ad4693b6473950e971b3dc525b5ee7570e05d0 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Mon, 11 Sep 2023 08:42:35 -0700 Subject: [PATCH 2/2] xfs: fix log recovery when unknown rocompat bits are set Log recovery has always run on read only mounts, even where the primary superblock advertises unknown rocompat bits. Due to a misunderstanding between Eric and Darrick back in 2018, we accidentally changed the superblock write verifier to shutdown the fs over that exact scenario. As a result, the log cleaning that occurs at the end of the mounting process fails if there are unknown rocompat bits set. As we now allow writing of the superblock if there are unknown rocompat bits set on a RO mount, we no longer want to turn off RO state to allow log recovery to succeed on a RO mount. Hence we also remove all the (now unnecessary) RO state toggling from the log recovery path. Fixes: 9e037cb7972f ("xfs: check for unknown v5 feature bits in superblock write verifier" Signed-off-by: Darrick J. Wong Reviewed-by: Dave Chinner --- fs/xfs/libxfs/xfs_sb.c | 3 ++- fs/xfs/xfs_log.c | 17 ----------------- 2 files changed, 2 insertions(+), 18 deletions(-) diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c index 5e174685a77c..6264daaab37b 100644 --- a/fs/xfs/libxfs/xfs_sb.c +++ b/fs/xfs/libxfs/xfs_sb.c @@ -266,7 +266,8 @@ xfs_validate_sb_write( return -EFSCORRUPTED; } - if (xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) { + if (!xfs_is_readonly(mp) && + xfs_sb_has_ro_compat_feature(sbp, XFS_SB_FEAT_RO_COMPAT_UNKNOWN)) { xfs_alert(mp, "Corruption detected in superblock read-only compatible features (0x%x)!", (sbp->sb_features_ro_compat & diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index 79004d193e54..51c100c86177 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -715,15 +715,7 @@ xfs_log_mount( * just worked. */ if (!xfs_has_norecovery(mp)) { - /* - * log recovery ignores readonly state and so we need to clear - * mount-based read only state so it can write to disk. - */ - bool readonly = test_and_clear_bit(XFS_OPSTATE_READONLY, - &mp->m_opstate); error = xlog_recover(log); - if (readonly) - set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate); if (error) { xfs_warn(mp, "log mount/recovery failed: error %d", error); @@ -772,7 +764,6 @@ xfs_log_mount_finish( struct xfs_mount *mp) { struct xlog *log = mp->m_log; - bool readonly; int error = 0; if (xfs_has_norecovery(mp)) { @@ -780,12 +771,6 @@ xfs_log_mount_finish( return 0; } - /* - * log recovery ignores readonly state and so we need to clear - * mount-based read only state so it can write to disk. - */ - readonly = test_and_clear_bit(XFS_OPSTATE_READONLY, &mp->m_opstate); - /* * During the second phase of log recovery, we need iget and * iput to behave like they do for an active filesystem. @@ -835,8 +820,6 @@ xfs_log_mount_finish( xfs_buftarg_drain(mp->m_ddev_targp); clear_bit(XLOG_RECOVERY_NEEDED, &log->l_opstate); - if (readonly) - set_bit(XFS_OPSTATE_READONLY, &mp->m_opstate); /* Make sure the log is dead if we're returning failure. */ ASSERT(!error || xlog_is_shutdown(log));