diff mbox series

[v6,5/7] xfs: switch to multigrain timestamps

Message ID 20230725-mgctime-v6-5-a794c2b7abca@kernel.org (mailing list archive)
State New, archived
Headers show
Series fs: implement multigrain timestamps | expand

Commit Message

Jeff Layton July 25, 2023, 2:58 p.m. UTC
Enable multigrain timestamps, which should ensure that there is an
apparent change to the timestamp whenever it has been written after
being actively observed via getattr.

Also, anytime the mtime changes, the ctime must also change, and those
are now the only two options for xfs_trans_ichgtime. Have that function
unconditionally bump the ctime, and ASSERT that XFS_ICHGTIME_CHG is
always set.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
---
 fs/xfs/libxfs/xfs_trans_inode.c | 6 +++---
 fs/xfs/xfs_iops.c               | 4 ++--
 fs/xfs/xfs_super.c              | 2 +-
 3 files changed, 6 insertions(+), 6 deletions(-)

Comments

Darrick J. Wong Aug. 2, 2023, 5:48 p.m. UTC | #1
On Tue, Jul 25, 2023 at 10:58:18AM -0400, Jeff Layton wrote:
> Enable multigrain timestamps, which should ensure that there is an
> apparent change to the timestamp whenever it has been written after
> being actively observed via getattr.
> 
> Also, anytime the mtime changes, the ctime must also change, and those
> are now the only two options for xfs_trans_ichgtime. Have that function
> unconditionally bump the ctime, and ASSERT that XFS_ICHGTIME_CHG is
> always set.
> 
> Signed-off-by: Jeff Layton <jlayton@kernel.org>
> ---
>  fs/xfs/libxfs/xfs_trans_inode.c | 6 +++---
>  fs/xfs/xfs_iops.c               | 4 ++--
>  fs/xfs/xfs_super.c              | 2 +-
>  3 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
> index 6b2296ff248a..ad22656376d3 100644
> --- a/fs/xfs/libxfs/xfs_trans_inode.c
> +++ b/fs/xfs/libxfs/xfs_trans_inode.c
> @@ -62,12 +62,12 @@ xfs_trans_ichgtime(
>  	ASSERT(tp);
>  	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
>  
> -	tv = current_time(inode);
> +	/* If the mtime changes, then ctime must also change */
> +	ASSERT(flags & XFS_ICHGTIME_CHG);
>  
> +	tv = inode_set_ctime_current(inode);
>  	if (flags & XFS_ICHGTIME_MOD)
>  		inode->i_mtime = tv;
> -	if (flags & XFS_ICHGTIME_CHG)
> -		inode_set_ctime_to_ts(inode, tv);
>  	if (flags & XFS_ICHGTIME_CREATE)
>  		ip->i_crtime = tv;
>  }
> diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> index 3a9363953ef2..3f89ef5a2820 100644
> --- a/fs/xfs/xfs_iops.c
> +++ b/fs/xfs/xfs_iops.c
> @@ -573,10 +573,10 @@ xfs_vn_getattr(
>  	stat->gid = vfsgid_into_kgid(vfsgid);
>  	stat->ino = ip->i_ino;
>  	stat->atime = inode->i_atime;
> -	stat->mtime = inode->i_mtime;
> -	stat->ctime = inode_get_ctime(inode);
>  	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
>  
> +	fill_mg_cmtime(request_mask, inode, stat);

Huh.  I would've thought @stat would come first since that's what we're
acting upon, but ... eh. :)

If everyone else is ok with the fill_mg_cmtime signature,
Acked-by: Darrick J. Wong <djwong@kernel.org>

--D

> +
>  	if (xfs_has_v3inodes(mp)) {
>  		if (request_mask & STATX_BTIME) {
>  			stat->result_mask |= STATX_BTIME;
> diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
> index 818510243130..4b10edb2c972 100644
> --- a/fs/xfs/xfs_super.c
> +++ b/fs/xfs/xfs_super.c
> @@ -2009,7 +2009,7 @@ static struct file_system_type xfs_fs_type = {
>  	.init_fs_context	= xfs_init_fs_context,
>  	.parameters		= xfs_fs_parameters,
>  	.kill_sb		= kill_block_super,
> -	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
> +	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME,
>  };
>  MODULE_ALIAS_FS("xfs");
>  
> 
> -- 
> 2.41.0
>
Jeff Layton Aug. 2, 2023, 6:21 p.m. UTC | #2
On Wed, 2023-08-02 at 10:48 -0700, Darrick J. Wong wrote:
> On Tue, Jul 25, 2023 at 10:58:18AM -0400, Jeff Layton wrote:
> > Enable multigrain timestamps, which should ensure that there is an
> > apparent change to the timestamp whenever it has been written after
> > being actively observed via getattr.
> > 
> > Also, anytime the mtime changes, the ctime must also change, and those
> > are now the only two options for xfs_trans_ichgtime. Have that function
> > unconditionally bump the ctime, and ASSERT that XFS_ICHGTIME_CHG is
> > always set.
> > 
> > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > ---
> >  fs/xfs/libxfs/xfs_trans_inode.c | 6 +++---
> >  fs/xfs/xfs_iops.c               | 4 ++--
> >  fs/xfs/xfs_super.c              | 2 +-
> >  3 files changed, 6 insertions(+), 6 deletions(-)
> > 
> > diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
> > index 6b2296ff248a..ad22656376d3 100644
> > --- a/fs/xfs/libxfs/xfs_trans_inode.c
> > +++ b/fs/xfs/libxfs/xfs_trans_inode.c
> > @@ -62,12 +62,12 @@ xfs_trans_ichgtime(
> >  	ASSERT(tp);
> >  	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
> >  
> > -	tv = current_time(inode);
> > +	/* If the mtime changes, then ctime must also change */
> > +	ASSERT(flags & XFS_ICHGTIME_CHG);
> >  
> > +	tv = inode_set_ctime_current(inode);
> >  	if (flags & XFS_ICHGTIME_MOD)
> >  		inode->i_mtime = tv;
> > -	if (flags & XFS_ICHGTIME_CHG)
> > -		inode_set_ctime_to_ts(inode, tv);
> >  	if (flags & XFS_ICHGTIME_CREATE)
> >  		ip->i_crtime = tv;
> >  }
> > diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> > index 3a9363953ef2..3f89ef5a2820 100644
> > --- a/fs/xfs/xfs_iops.c
> > +++ b/fs/xfs/xfs_iops.c
> > @@ -573,10 +573,10 @@ xfs_vn_getattr(
> >  	stat->gid = vfsgid_into_kgid(vfsgid);
> >  	stat->ino = ip->i_ino;
> >  	stat->atime = inode->i_atime;
> > -	stat->mtime = inode->i_mtime;
> > -	stat->ctime = inode_get_ctime(inode);
> >  	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
> >  
> > +	fill_mg_cmtime(request_mask, inode, stat);
> 
> Huh.  I would've thought @stat would come first since that's what we're
> acting upon, but ... eh. :)
> 
> If everyone else is ok with the fill_mg_cmtime signature,
> Acked-by: Darrick J. Wong <djwong@kernel.org>
> 
> 

Good point. We can change the signature. I think xfs is the only caller
outside of the generic vfs right now, and it'd be best to do it now.

Christian, would you prefer that I send an updated series, or patches on
top of vfs.ctime that can be folded in?
Christian Brauner Aug. 3, 2023, 7:05 a.m. UTC | #3
On Wed, Aug 02, 2023 at 02:21:49PM -0400, Jeff Layton wrote:
> On Wed, 2023-08-02 at 10:48 -0700, Darrick J. Wong wrote:
> > On Tue, Jul 25, 2023 at 10:58:18AM -0400, Jeff Layton wrote:
> > > Enable multigrain timestamps, which should ensure that there is an
> > > apparent change to the timestamp whenever it has been written after
> > > being actively observed via getattr.
> > > 
> > > Also, anytime the mtime changes, the ctime must also change, and those
> > > are now the only two options for xfs_trans_ichgtime. Have that function
> > > unconditionally bump the ctime, and ASSERT that XFS_ICHGTIME_CHG is
> > > always set.
> > > 
> > > Signed-off-by: Jeff Layton <jlayton@kernel.org>
> > > ---
> > >  fs/xfs/libxfs/xfs_trans_inode.c | 6 +++---
> > >  fs/xfs/xfs_iops.c               | 4 ++--
> > >  fs/xfs/xfs_super.c              | 2 +-
> > >  3 files changed, 6 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
> > > index 6b2296ff248a..ad22656376d3 100644
> > > --- a/fs/xfs/libxfs/xfs_trans_inode.c
> > > +++ b/fs/xfs/libxfs/xfs_trans_inode.c
> > > @@ -62,12 +62,12 @@ xfs_trans_ichgtime(
> > >  	ASSERT(tp);
> > >  	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
> > >  
> > > -	tv = current_time(inode);
> > > +	/* If the mtime changes, then ctime must also change */
> > > +	ASSERT(flags & XFS_ICHGTIME_CHG);
> > >  
> > > +	tv = inode_set_ctime_current(inode);
> > >  	if (flags & XFS_ICHGTIME_MOD)
> > >  		inode->i_mtime = tv;
> > > -	if (flags & XFS_ICHGTIME_CHG)
> > > -		inode_set_ctime_to_ts(inode, tv);
> > >  	if (flags & XFS_ICHGTIME_CREATE)
> > >  		ip->i_crtime = tv;
> > >  }
> > > diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
> > > index 3a9363953ef2..3f89ef5a2820 100644
> > > --- a/fs/xfs/xfs_iops.c
> > > +++ b/fs/xfs/xfs_iops.c
> > > @@ -573,10 +573,10 @@ xfs_vn_getattr(
> > >  	stat->gid = vfsgid_into_kgid(vfsgid);
> > >  	stat->ino = ip->i_ino;
> > >  	stat->atime = inode->i_atime;
> > > -	stat->mtime = inode->i_mtime;
> > > -	stat->ctime = inode_get_ctime(inode);
> > >  	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
> > >  
> > > +	fill_mg_cmtime(request_mask, inode, stat);
> > 
> > Huh.  I would've thought @stat would come first since that's what we're
> > acting upon, but ... eh. :)
> > 
> > If everyone else is ok with the fill_mg_cmtime signature,
> > Acked-by: Darrick J. Wong <djwong@kernel.org>
> > 
> > 
> 
> Good point. We can change the signature. I think xfs is the only caller
> outside of the generic vfs right now, and it'd be best to do it now.
> 
> Christian, would you prefer that I send an updated series, or patches on
> top of vfs.ctime that can be folded in?

Let's fold instead of inundate everyone with almost 100 patches.
When I'll apply I'll remind everyone where the series can be pulled
from anyway.
diff mbox series

Patch

diff --git a/fs/xfs/libxfs/xfs_trans_inode.c b/fs/xfs/libxfs/xfs_trans_inode.c
index 6b2296ff248a..ad22656376d3 100644
--- a/fs/xfs/libxfs/xfs_trans_inode.c
+++ b/fs/xfs/libxfs/xfs_trans_inode.c
@@ -62,12 +62,12 @@  xfs_trans_ichgtime(
 	ASSERT(tp);
 	ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL));
 
-	tv = current_time(inode);
+	/* If the mtime changes, then ctime must also change */
+	ASSERT(flags & XFS_ICHGTIME_CHG);
 
+	tv = inode_set_ctime_current(inode);
 	if (flags & XFS_ICHGTIME_MOD)
 		inode->i_mtime = tv;
-	if (flags & XFS_ICHGTIME_CHG)
-		inode_set_ctime_to_ts(inode, tv);
 	if (flags & XFS_ICHGTIME_CREATE)
 		ip->i_crtime = tv;
 }
diff --git a/fs/xfs/xfs_iops.c b/fs/xfs/xfs_iops.c
index 3a9363953ef2..3f89ef5a2820 100644
--- a/fs/xfs/xfs_iops.c
+++ b/fs/xfs/xfs_iops.c
@@ -573,10 +573,10 @@  xfs_vn_getattr(
 	stat->gid = vfsgid_into_kgid(vfsgid);
 	stat->ino = ip->i_ino;
 	stat->atime = inode->i_atime;
-	stat->mtime = inode->i_mtime;
-	stat->ctime = inode_get_ctime(inode);
 	stat->blocks = XFS_FSB_TO_BB(mp, ip->i_nblocks + ip->i_delayed_blks);
 
+	fill_mg_cmtime(request_mask, inode, stat);
+
 	if (xfs_has_v3inodes(mp)) {
 		if (request_mask & STATX_BTIME) {
 			stat->result_mask |= STATX_BTIME;
diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 818510243130..4b10edb2c972 100644
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -2009,7 +2009,7 @@  static struct file_system_type xfs_fs_type = {
 	.init_fs_context	= xfs_init_fs_context,
 	.parameters		= xfs_fs_parameters,
 	.kill_sb		= kill_block_super,
-	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
+	.fs_flags		= FS_REQUIRES_DEV | FS_ALLOW_IDMAP | FS_MGTIME,
 };
 MODULE_ALIAS_FS("xfs");