[PATCH v3 00/14] md: cleanup on direct access to bvec table

Ming Lei
2017-03-16T16:14:20Z

In MD's resync I/O path, there are lots of direct access to bio's
bvec table. This patchset kills almost all, and the conversion
is quite straightforward. One root cause of direct access to bvec
table is that resync I/O uses the bio's bvec to manage pages.
In V1, as suggested by Shaohua, a new approach is used to manage
these pages for resync I/O, turns out code becomes more clean
and readable.

Once direct access to bvec table in MD is cleaned up, we may make
multipage bvec moving on.

V3:
- improve pages allocation & bio clone for write behind(10/14)
- retrieve pages from preallocated page array, and avoid to user
bio helpers(14/14)
- change on helpers about managing resync io pages(03/14)

V2:
- remove the patch for introducing/applying bio_remove_last_page()

V1:
- allocate page array to manage resync pages

Thanks,
Ming

Ming Lei (14):
md: raid1/raid10: don't handle failure of bio_add_page()
md: move two macros into md.h
md: prepare for managing resync I/O pages in clean way
md: raid1: simplify r1buf_pool_free()
md: raid1: don't use bio's vec table to manage resync pages
md: raid1: retrieve page from pre-allocated resync page array
md: raid1: use bio helper in process_checks()
block: introduce bio_copy_data_partial
md: raid1: move 'offset' out of loop
md: raid1: improve write behind
md: raid10: refactor code of read reshape's .bi_end_io
md: raid10: don't use bio's vec table to manage resync pages
md: raid10: retrieve page from preallocated resync page array
md: raid10: avoid direct access to bvec table in
handle_reshape_read_error

block/bio.c | 60 +++++++++---
drivers/md/md.h | 55 +++++++++++
drivers/md/raid1.c | 267 ++++++++++++++++++++++++++++------------------------
drivers/md/raid1.h | 10 +-
drivers/md/raid10.c | 224 +++++++++++++++++++++++--------------------
include/linux/bio.h | 2 +
6 files changed, 376 insertions(+), 242 deletions(-)

--
2.9.3