Re: [PATCH v3 4/4] PM: submit bio in a sane way in cases without bio_chain

[Christoph Hellwig]

On Thu, Apr 23, 2015 at 04:04:35PM -0700, Ming Lin wrote:
> From: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> 
> Make bio submission in kernel/power/block_io.c to properly submit
> bios also when bio_chain is not available. In that case, it's not
> necessary to handle refcount with bio_get(), but it's saner to simply
> call a predefined helper submit_bio_wait(). So call bio_get() only
> when bio_chain is given.

The patch looks correct, buth that whole code is a f****ing mess.

For one it really shouldn't mess with pages states nor abuse
end_swap_bio_read.

Something like the untested patch below should do it, but it really
needs some solid testing from people that know how to even exercise
it.

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