libnvdimm, nfit, nd_blk: driver for BLK-mode access persistent memory

The libnvdimm 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 libnvdimm 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 <luto@amacapital.net>
Cc: Boaz Harrosh <boaz@plexistor.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jens Axboe <axboe@fb.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 5e6413964776..e1970c71ad1c 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -43,9 +43,8 @@ struct nvdimm {
 };
 
 bool is_nvdimm(struct device *dev);
-bool is_nd_blk(struct device *dev);
 bool is_nd_pmem(struct device *dev);
-struct nd_btt;
+bool is_nd_blk(struct device *dev);
 struct nvdimm_bus *walk_to_nvdimm_bus(struct device *nd_dev);
 int __init nvdimm_bus_init(void);
 void nvdimm_bus_exit(void);