[dm-devel] [PATCH] dm-writecache

[Christoph Hellwig]

> --- /dev/null	1970-01-01 00:00:00.000000000 +0000
> +++ linux-2.6/drivers/md/dm-writecache.c	2018-03-08 14:23:31.059999000 +0100
> @@ -0,0 +1,2417 @@
> +#include <linux/device-mapper.h>

missing copyright statement, or for those new-fashioned SPDX statement.

> +#define WRITEBACK_FUA			true

no business having this around.

> +#ifndef bio_set_dev
> +#define	bio_set_dev(bio, dev)	((bio)->bi_bdev = (dev))
> +#endif
> +#ifndef timer_setup
> +#define timer_setup(t, c, f)	setup_timer(t, c, (unsigned long)(t))
> +#endif

no business in mainline.

> +/*
> + * On X86, non-temporal stores are more efficient than cache flushing.
> + * On ARM64, cache flushing is more efficient.
> + */
> +#if defined(CONFIG_X86_64)
> +#define NT_STORE(dest, src)				\
> +do {							\
> +	typeof(src) val = (src);			\
> +	memcpy_flushcache(&(dest), &val, sizeof(src));	\
> +} while (0)
> +#define COMMIT_FLUSHED()	wmb()
> +#else
> +#define NT_STORE(dest, src)	WRITE_ONCE(dest, src)
> +#define FLUSH_RANGE		dax_flush
> +#define COMMIT_FLUSHED()	do { } while (0)
> +#endif

Please use proper APIs for this, this has no business in a driver.

And that's it for now.  This is clearly not submission ready, and I
should got back to my backlog of other things.