Re: [PATCH v3 0/5] btrfs: remove buffer heads form superblock handling

[David Sterba <dsterba@suse.cz>]

On Tue, Jan 28, 2020 at 12:59:26AM +0900, Johannes Thumshirn wrote:
> This patch series removes the use of buffer_heads from btrfs' super block read
> and write paths. It also converts the integrity-checking code to only work
> with pages and BIOs.
> 
> Compared to buffer heads, this gives us a leaner call path, as the
> buffer_head code wraps around getting pages from the page-cache and adding
> them to BIOs to submit.
> 
> The first patch removes buffer_heads from superblock reading.  The second
> removes it from super_block writing and the subsequent patches remove the
> buffer_heads from the integrity check code.
> 
> It's based on misc-next from Wednesday January 22, and doesn't show any
> regressions in xfstests to the baseline.
> 
> Changes to v2:
> - Removed patch #1 again
> - Added Reviews from Josef
> - Re-visited page locking, but not changes, it retains the same locking scheme
>   the buffer_heads had
> - Incroptorated comments from David regarding open-coding functions
> - For more details see the idividual patches.
> 
> 
> Changes to v1:
> - Added patch #1
> - Converted sb reading and integrity checking to use the page cache
> - Added rationale behind the conversion to the commit messages.
> - For more details see the idividual patches.
> 
> 
> Johannes Thumshirn (5):
>   btrfs: remove buffer heads from super block reading
>   btrfs: remove use of buffer_heads from superblock writeout

For next iteration, please change the subjects of the two patches to say
"replace buffer heads with bio for superblock reading". Thanks.