Re: [PATCH 00/21] drop vmtruncate

["Lukáš Czerner" <lczerner@redhat.com>]

On Fri, 31 Aug 2012, Marco Stornelli wrote:

> Date: Fri, 31 Aug 2012 15:50:20 +0200
> From: Marco Stornelli <marco.stornelli@gmail.com>
> To: Linux FS Devel <linux-fsdevel@vger.kernel.org>, linux-mm@kvack.org
> Cc: Linux Kernel <linux-kernel@vger.kernel.org>
> Subject: [PATCH 00/21] drop vmtruncate
> 
> Hi all,
> 
> with this patch series I try to clean the vmtruncate code. The theory of
> operation:
> 
> old               new
> vmtruncate() =>   inode_newsize_ok+truncate_setsize+fs truncate
> 
> Where vmtruncate was used without any error check, the code now is:
> 
> if (inode_newsize_ok() == 0) {
> 	truncate_setsize();
> 	fs truncate();
> }
> 
> So, performance and semantic nothing change at all. I think that maybe in some
> point we can skip inode_newsize_ok (where the error check of vmtruncate wasn't
> used) but since there is a swap check in case of no-extension, maybe it's
> better to avoid regressions. After this clean, of course, each fs can clean in
> a deeply way.
> 
> With these patches even the inode truncate callback is deleted.
> 
> Any comments/feedback/bugs are welcome.

Could you explain the reason behind this change a little bit more ?
This does not make any sense to me since you're replacing
vmtruncate() which does basically 

if (inode_newsize_ok() == 0) {
	truncate_setsize();
	fs truncate();
}

as you mentioned above by exactly the same thing but doing it within
the file system. It does not seem like an improvement to me ... how
is this a clean up ?

Thanks!
-Lukas

> 
> Marco Stornelli (21):
>   ufs: drop vmtruncate
>   sysv: drop vmtruncate
>   reiserfs: drop vmtruncate
>   procfs: drop vmtruncate
>   omfs: drop vmtruncate
>   ocfs2: drop vmtruncate
>   adfs: drop vmtruncate
>   affs: drop vmtruncate
>   bfs: drop vmtruncate
>   hfs: drop vmtruncate
>   hpfs: drop vmtruncate
>   jfs: drop vmtruncate
>   hfsplus: drop vmtruncate
>   hostfs: drop vmtruncate
>   logfs: drop vmtruncate
>   minix: drop vmtruncate
>   ncpfs: drop vmtruncate
>   nilfs2: drop vmtruncate
>   ntfs: drop vmtruncate
>   vfs: drop vmtruncate
>   mm: drop vmtruncate
> 
>  fs/adfs/inode.c         |    5 +++--
>  fs/affs/file.c          |    8 +++++---
>  fs/affs/inode.c         |    5 ++++-
>  fs/bfs/file.c           |    5 +++--
>  fs/hfs/inode.c          |   19 +++++++++++++------
>  fs/hfsplus/inode.c      |   19 +++++++++++++------
>  fs/hostfs/hostfs_kern.c |    8 +++++---
>  fs/hpfs/file.c          |    8 +++++---
>  fs/hpfs/inode.c         |    5 ++++-
>  fs/jfs/file.c           |    6 ++++--
>  fs/jfs/inode.c          |   13 +++++++++----
>  fs/libfs.c              |    2 --
>  fs/logfs/readwrite.c    |   10 ++++++++--
>  fs/minix/file.c         |    6 ++++--
>  fs/minix/inode.c        |    7 +++++--
>  fs/ncpfs/inode.c        |    4 +++-
>  fs/nilfs2/file.c        |    1 -
>  fs/nilfs2/inode.c       |   18 +++++++++++++-----
>  fs/nilfs2/recovery.c    |    7 +++++--
>  fs/ntfs/file.c          |    8 +++++---
>  fs/ntfs/inode.c         |   11 +++++++++--
>  fs/ntfs/inode.h         |    4 ++++
>  fs/ocfs2/file.c         |    3 ++-
>  fs/omfs/file.c          |   12 ++++++++----
>  fs/proc/base.c          |    3 ++-
>  fs/proc/generic.c       |    3 ++-
>  fs/proc/proc_sysctl.c   |    3 ++-
>  fs/reiserfs/file.c      |    3 +--
>  fs/reiserfs/inode.c     |   15 +++++++++++----
>  fs/reiserfs/reiserfs.h  |    1 +
>  fs/sysv/file.c          |    5 +++--
>  fs/sysv/itree.c         |    7 +++++--
>  fs/ufs/inode.c          |    5 +++--
>  include/linux/fs.h      |    1 -
>  include/linux/mm.h      |    1 -
>  mm/truncate.c           |   23 -----------------------
>  36 files changed, 164 insertions(+), 100 deletions(-)
> 
>