libnvdimm, pmem: allow nfit_test to override pmem_direct_access()

Currently phys_to_pfn_t() is an exported symbol to allow nfit_test to
override it and indicate that nfit_test-pmem is not device-mapped.  Now,
we want to enable nfit_test to operate without DMA_CMA and the pmem it
provides will no longer be physically contiguous, i.e. won't be capable
of supporting direct_access requests larger than a page.  Make
pmem_direct_access() a weak symbol so that it can be replaced by the
tools/testing/nvdimm/ version, and move phys_to_pfn_t() to a static
inline now that it no longer needs to be overridden.

Acked-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 3 insertions, 15 deletions

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index ba253df..b6fcb97 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -29,23 +29,10 @@
 #include <linux/slab.h>
 #include <linux/pmem.h>
 #include <linux/nd.h>
+#include "pmem.h"
 #include "pfn.h"
 #include "nd.h"
 
-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 __pmem		*virt_addr;
-	/* immutable base size of the namespace */
-	size_t			size;
-	/* trim size when namespace capacity has been section aligned */
-	u32			pfn_pad;
-	struct badblocks	bb;
-};
-
 static void pmem_clear_poison(struct pmem_device *pmem, phys_addr_t offset,
 		unsigned int len)
 {
@@ -163,7 +150,8 @@ static int pmem_rw_page(struct block_device *bdev, sector_t sector,
 	return rc;
 }
 
-static long pmem_direct_access(struct block_device *bdev, sector_t sector,
+/* see "strong" declaration in tools/testing/nvdimm/pmem-dax.c */
+__weak long pmem_direct_access(struct block_device *bdev, sector_t sector,
 		      void __pmem **kaddr, pfn_t *pfn, long size)
 {
 	struct pmem_device *pmem = bdev->bd_queue->queuedata;