[PATCH 1/5] xfs: remove ->write_super and stop maintaining ->s_dirt

[Eric Sandeen]

Christoph Hellwig wrote:

> the write_super method is used for
> 
>  (1) writing back the superblock periodically from pdflush
>  (2) called just before ->sync_fs for data integerity syncs
>  (3) just before ->put_super
> 
> We don't need (1) because we have our own peridoc writeout through xfssyncd,
> we don't need (2) because xfs_fs_sync_fs performs a proper synchronous
> superblock writeout after all other data and metadata has been written out,
> and we don't need (3) because we synchronously write the superblock in
> ->put_super once the filesystem is fully shut down.
> 
> Also remove ->s_dirt tracking as it's only used to decide when too call
> ->write_super.
> 
> 
> Signed-off-by: Christoph Hellwig <hch at lst.de>

Reviewed-by: Eric Sandeen <sandeen at sandeen.net>