[RFC PATCH 5/6] io_uring: add support for uring_cmd with fixed-buffer

[Christoph Hellwig]

On Thu, Aug 05, 2021 at 06:25:38PM +0530, Kanchan Joshi wrote:
> From: Anuj Gupta <anuj20.g at samsung.com>
> 
> Add IORING_OP_URING_CMD_FIXED opcode that enables performing the
> operation with previously registered buffers.

We should also pass this information on into ->uring_cmd instead of
needing two ioctl_cmd opcodes.