Re: [Linux-nvdimm] [PATCH 19/21] nd: infrastructure for btt devices

[Christoph Hellwig]

On Fri, Apr 17, 2015 at 09:36:55PM -0400, Dan Williams wrote:
> Block devices from an nd bus, in addition to accepting "struct bio"
> based requests, also have the capability to perform byte-aligned
> accesses.  By default only the bio/block interface is used.  However, if
> another driver can make effective use of the byte-aligned capability it
> can claim/disable the block interface and use the byte-aligned "nd_io"
> interface.
> 
> The BTT driver is the intended first consumer of this mechanism to allow
> layering atomic sector update guarantees on top of nd_io capable
> nd-bus-block-devices.

Please don't add any of the nd-specific hacks into the pmem driver.
The rw_bytes functionality already is provided by the existing block
level ->rw_page method which pmem already implements, and any sort
of bus locking for different access methods should be in the bus
glue, not in pmem.c
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/