Re: [PATCH 1/8] nowait aio: Introduce IOCB_RW_FLAG_NOWAIT

On Mon, Apr 03, 2017 at 01:53:00PM -0500, Goldwyn Rodrigues wrote:

From: Goldwyn Rodrigues <redacted>

This flag informs kernel to bail out if an AIO request will block
for reasons such as file allocations, or a writeback triggered,
or would block while allocating requests while performing
direct I/O.

Unfortunately, aio_flags is not checked for validity, which would
break existing applications which have it set to anything besides zero
or IOCB_FLAG_RESFD. So, we are using aio_reserved1 and renaming it
to aio_rw_flags.

IOCB_RW_FLAG_NOWAIT is translated to IOCB_NOWAIT for
iocb->ki_flags.

Please make this a flag in the RWF_* namespace, and as a preparation
support the existing RWF_* flags for aio.