Re: [Cluster-devel] [PATCH 00/10] gfs2 iomap buffered write support

[Steven Whitehouse <swhiteho@redhat.com>]

Hi,


On 11/01/18 21:14, Andreas Gruenbacher wrote:
> Hello,
>
> this patch queue converts gfs2 to use iomap for buffered writes, which
> uses multi-page block allocations for large writes instead of requiring
> a separate allocation for each page of data.
>
> The patches apply on top of the gfs2 punch-hole patch queue [*].
>
> So far, the only user of iomap_file_buffered_write was xfs, which
> doesn't do data journaling.  To support gfs2's data journaling, patch
> 08/10 adds a new iomap_written iomap operation: if defined, this
> operation is called by iomap_file_buffered_write whenever a page has
> been written to.
>
> This patch queue doesn't convert direct I/O, so we still have a
> remaining user of the old gfs2_write_begin / gfs2_write_end interface
> left.  Once direct I/O has been converted to use iomap, we'll get rid of
> that code, though.
>
> Thanks,
> Andreas
>
> [*] https://www.redhat.com/archives/cluster-devel/2017-December/msg00089.html
>
> Andreas Gruenbacher (10):
>    gfs2: Typo fixes
>    gfs2: Add gfs2_max_stuffed_size
>    gfs2: Minor gfs2_page_add_databufs cleanup
>    gfs2: gfs2_stuffed_write_end cleanup
>    gfs2: gfs2_stuffed_write_end cleanup (fixup)
>    gfs2: Remove ordered write mode handling from gfs2_trans_add_data
>    gfs2: Iomap cleanups and improvements
>    iomap: New iomap_written operation
>    gfs2: Implement iomap buffered write support (1)
>    gfs2: Implement iomap buffered write support (2)
It looks like patches 1 to 3 inclusive could be sent right away as they 
are worthwhile clean ups in their own right - no need to delay those. 
Patches 4 and 5 should be merged into one I think. Otherwise it looks 
like everything is going in the right direction generally, the other 
comments which have been made notwithstanding,

Steve.

>
>   fs/gfs2/aops.c        | 178 ++++++++++++++++------
>   fs/gfs2/aops.h        |  19 +++
>   fs/gfs2/bmap.c        | 407 +++++++++++++++++++++++++++++++++++++-------------
>   fs/gfs2/bmap.h        |   5 +-
>   fs/gfs2/dir.c         |   3 +-
>   fs/gfs2/file.c        |  49 +++++-
>   fs/gfs2/incore.h      |   5 +
>   fs/gfs2/inode.c       |  10 +-
>   fs/gfs2/log.h         |   7 +-
>   fs/gfs2/quota.c       |   5 +-
>   fs/gfs2/trans.c       |  27 +---
>   fs/iomap.c            |  21 ++-
>   include/linux/iomap.h |   9 ++
>   13 files changed, 558 insertions(+), 187 deletions(-)
>   create mode 100644 fs/gfs2/aops.h
>