alistair23-linux/drivers/nvdimm/pmem.h
Robin Murphy 5deb67f77a libnvdimm, nd_blk: remove mmio_flush_range()
mmio_flush_range() suffers from a lack of clearly-defined semantics,
and is somewhat ambiguous to port to other architectures where the
scope of the writeback implied by "flush" and ordering might matter,
but MMIO would tend to imply non-cacheable anyway. Per the rationale
in 67a3e8fe90 ("nd_blk: change aperture mapping from WC to WB"), the
only existing use is actually to invalidate clean cache lines for
ARCH_MEMREMAP_PMEM type mappings *without* writeback. Since the recent
cleanup of the pmem API, that also now happens to be the exact purpose
of arch_invalidate_pmem(), which would be a far more well-defined tool
for the job.

Rather than risk potentially inconsistent implementations of
mmio_flush_range() for the sake of one callsite, streamline things by
removing it entirely and instead move the ARCH_MEMREMAP_PMEM related
definitions up to the libnvdimm level, so they can be shared by NFIT
as well. This allows NFIT to be enabled for arm64.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2017-08-31 15:05:10 -07:00

29 lines
847 B
C

#ifndef __NVDIMM_PMEM_H__
#define __NVDIMM_PMEM_H__
#include <linux/badblocks.h>
#include <linux/types.h>
#include <linux/pfn_t.h>
#include <linux/fs.h>
/* this definition is in it's own header for tools/testing/nvdimm to consume */
struct pmem_device {
/* One contiguous memory region per device */
phys_addr_t phys_addr;
/* when non-zero this device is hosting a 'pfn' instance */
phys_addr_t data_offset;
u64 pfn_flags;
void *virt_addr;
/* immutable base size of the namespace */
size_t size;
/* trim size when namespace capacity has been section aligned */
u32 pfn_pad;
struct kernfs_node *bb_state;
struct badblocks bb;
struct dax_device *dax_dev;
struct gendisk *disk;
};
long __pmem_direct_access(struct pmem_device *pmem, pgoff_t pgoff,
long nr_pages, void **kaddr, pfn_t *pfn);
#endif /* __NVDIMM_PMEM_H__ */