[PATCH for-next v4 0/4] fixed-buffer for uring-cmd/passthru

[Kanchan Joshi]

Hi,

Currently uring-cmd lacks the ability to leverage the pre-registered
buffers. This series adds that support in uring-cmd, and plumbs
nvme passthrough to work with it.

Using registered-buffers showed IOPS hike from 1.9M to 2.2M to me.

Patch 1, 3 = prep/infrastructure
Patch 2 = expand io_uring command to use registered-buffers
Patch 4 = expand nvme passthrough to use registered-buffers

Changes since v3:
- uring_cmd_flags, change from u16 to u32 (Jens)
- patch 3, add another helper to reduce code-duplication (Jens)

Changes since v2:
- Kill the new opcode, add a flag instead (Pavel)
- Fix standalone build issue with patch 1 (Pavel)

Changes since v1:
- Fix a naming issue for an exported helper

Anuj Gupta (2):
  io_uring: introduce io_uring_cmd_import_fixed
  io_uring: introduce fixed buffer support for io_uring_cmd

Kanchan Joshi (2):
  block: add helper to map bvec iterator for passthrough
  nvme: wire up fixed buffer support for nvme passthrough

 block/blk-map.c               | 94 +++++++++++++++++++++++++++++++----
 drivers/nvme/host/ioctl.c     | 38 +++++++++-----
 include/linux/blk-mq.h        |  1 +
 include/linux/io_uring.h      | 11 +++-
 include/uapi/linux/io_uring.h |  9 ++++
 io_uring/uring_cmd.c          | 29 ++++++++++-
 6 files changed, 158 insertions(+), 24 deletions(-)

-- 
2.25.1