[Qemu-devel] [PATCH v2 0/3] block: BDRV_REQ_PREFETCH

[Vladimir Sementsov-Ogievskiy]

Hi all!

Here is small new read flag: BDRV_REQ_PREFETCH, which in combination with
BDRV_REQ_COPY_ON_READ does copy-on-read without
extra buffer for read data. This means that only parts that needs COR
will be actually read and only corresponding buffers allocated, no more.

This allows to improve a bit block-stream and NBD_CMD_CACHE

v2: change interface to be just one flag BDRV_REQ_PREFETCH

v1 was "[PATCH 0/3] block: blk_co_pcache"
   https://lists.gnu.org/archive/html/qemu-devel/2019-06/msg01047.html

Vladimir Sementsov-Ogievskiy (3):
  block: implement BDRV_REQ_PREFETCH
  block/stream: use BDRV_REQ_PREFETCH
  nbd: improve CMD_CACHE: use blk_co_pcache

 include/block/block.h |  8 +++++++-
 block/io.c            | 18 ++++++++++++------
 block/stream.c        | 20 +++++++-------------
 nbd/server.c          | 43 +++++++++++++++++++++++++++++++++++--------
 4 files changed, 61 insertions(+), 28 deletions(-)

-- 
2.18.0