On Tue, Apr 28, 2015 at 11:26 AM, Dan Williams <[email protected]> wrote: > From: Ross Zwisler <[email protected]> > > The libnd implementation handles allocating dimm address space (DPA) > between PMEM and BLK mode interfaces. After DPA has been allocated from > a BLK-region to a BLK-namespace the nd_blk driver attaches to handle I/O > as a struct bio based block device. Unlike PMEM, BLK is required to > handle platform specific details like mmio register formats and memory > controller interleave. For this reason the libnd generic nd_blk driver > calls back into the bus provider to carry out the I/O. > > This initial implementation handles the BLK interface defined by the > ACPI 6 NFIT [1] and the NVDIMM DSM Interface Example [2] composed from > DCR (dimm control region), BDW (block data window), IDT (interleave > descriptor) NFIT structures and the hardware register format. > [1]: http://www.uefi.org/sites/default/files/resources/ACPI_6.0.pdf > [2]: http://pmem.io/documents/NVDIMM_DSM_Interface_Example.pdf > > Cc: Andy Lutomirski <[email protected]> > Cc: Boaz Harrosh <[email protected]> > Cc: H. Peter Anvin <[email protected]> > Cc: Jens Axboe <[email protected]> > Cc: Ingo Molnar <[email protected]> > Cc: Christoph Hellwig <[email protected]> > Signed-off-by: Ross Zwisler <[email protected]> > Signed-off-by: Dan Williams <[email protected]> > --- > drivers/block/nd/Kconfig | 12 + > drivers/block/nd/Makefile | 3 > drivers/block/nd/acpi.c | 422 > +++++++++++++++++++++++++++++++++++-- > drivers/block/nd/acpi_nfit.h | 47 ++++ > drivers/block/nd/blk.c | 264 +++++++++++++++++++++++ > drivers/block/nd/libnd.h | 11 + > drivers/block/nd/namespace_devs.c | 47 ++++ > drivers/block/nd/nd-private.h | 3 > drivers/block/nd/nd.h | 16 + > drivers/block/nd/region.c | 8 + > drivers/block/nd/region_devs.c | 65 +++++- > drivers/block/nd/test/nfit.c | 29 +++ > drivers/block/nd/test/nfit_test.h | 2 > 13 files changed, 891 insertions(+), 38 deletions(-) > create mode 100644 drivers/block/nd/blk.c > > diff --git a/drivers/block/nd/Kconfig b/drivers/block/nd/Kconfig > index 612bf2b14283..bac4290129fc 100644 > --- a/drivers/block/nd/Kconfig > +++ b/drivers/block/nd/Kconfig > @@ -95,6 +95,18 @@ config BLK_DEV_PMEM > > Say Y if you want to use a NVDIMM described by ACPI, E820, etc... > > +config ND_BLK > + tristate "BLK: Block data window (aperture) device support" > + depends on LIBND > + default ND_ACPI > + help > + This driver performs I/O using a set of mmio windows on a > + dimm. The set of apertures will all access the one DIMM. > + Multiple windows allow multiple threads to have a different > + portions of the dimm open at one time. > + > + Say Y if you want to use a NVDIMM with BLK-mode capability > +
This describes how it works, not what it is. How about: This driver exposes NVDIMM BLK regions as block devices. BLK regions are regions of NVDIMM storage that are sector-addressable, not byte-addressible, and do not support DAX. Say Y if you want to... --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
