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>

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index ba253df..b6fcb97 100644 (file)
--- 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;

diff --git a/drivers/nvdimm/pmem.h b/drivers/nvdimm/pmem.h
new file mode 100644 (file)
index 0000000..c48d4e3
--- /dev/null
+++ b/drivers/nvdimm/pmem.h
@@ -0,0 +1,24 @@
+#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>
+
+long pmem_direct_access(struct block_device *bdev, sector_t sector,
+                     void __pmem **kaddr, pfn_t *pfn, long size);
+/* 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 __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;
+};
+#endif /* __NVDIMM_PMEM_H__ */

diff --git a/include/linux/pfn_t.h b/include/linux/pfn_t.h
index 9499481..a3d90b9 100644 (file)
--- a/include/linux/pfn_t.h
+++ b/include/linux/pfn_t.h
@@ -28,7 +28,10 @@ static inline pfn_t pfn_to_pfn_t(unsigned long pfn)
        return __pfn_to_pfn_t(pfn, 0);
 }
 
-extern pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags);
+static inline pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
+{
+       return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
+}
 
 static inline bool pfn_t_has_page(pfn_t pfn)
 {

diff --git a/kernel/memremap.c b/kernel/memremap.c
index 0175321..852e526 100644 (file)
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -169,12 +169,6 @@ void devm_memunmap(struct device *dev, void *addr)
 }
 EXPORT_SYMBOL(devm_memunmap);
 
-pfn_t phys_to_pfn_t(phys_addr_t addr, u64 flags)
-{
-       return __pfn_to_pfn_t(addr >> PAGE_SHIFT, flags);
-}
-EXPORT_SYMBOL(phys_to_pfn_t);
-
 #ifdef CONFIG_ZONE_DEVICE
 static DEFINE_MUTEX(pgmap_lock);
 static RADIX_TREE(pgmap_radix, GFP_KERNEL);

diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index 7859856..4adfa9c 100644 (file)
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -11,12 +11,12 @@ ldflags-y += --wrap=__devm_release_region
 ldflags-y += --wrap=__request_region
 ldflags-y += --wrap=__release_region
 ldflags-y += --wrap=devm_memremap_pages
-ldflags-y += --wrap=phys_to_pfn_t
 
 DRIVERS := ../../../drivers
 NVDIMM_SRC := $(DRIVERS)/nvdimm
 ACPI_SRC := $(DRIVERS)/acpi
 DAX_SRC := $(DRIVERS)/dax
+ccflags-y := -I$(src)/$(NVDIMM_SRC)/
 
 obj-$(CONFIG_LIBNVDIMM) += libnvdimm.o
 obj-$(CONFIG_BLK_DEV_PMEM) += nd_pmem.o
@@ -31,6 +31,7 @@ nfit-y := $(ACPI_SRC)/nfit.o
 nfit-y += config_check.o
 
 nd_pmem-y := $(NVDIMM_SRC)/pmem.o
+nd_pmem-y += pmem-dax.o
 nd_pmem-y += config_check.o
 
 nd_btt-y := $(NVDIMM_SRC)/btt.o

diff --git a/tools/testing/nvdimm/pmem-dax.c b/tools/testing/nvdimm/pmem-dax.c
new file mode 100644 (file)
index 0000000..fdba77f
--- /dev/null
+++ b/tools/testing/nvdimm/pmem-dax.c
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2014-2016, Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ */
+#include "test/nfit_test.h"
+#include <linux/blkdev.h>
+#include <pmem.h>
+#include <nd.h>
+
+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;
+       resource_size_t offset = sector * 512 + pmem->data_offset;
+
+       /* disable DAX for nfit_test pmem devices */
+       if (get_nfit_res(pmem->phys_addr + offset)) {
+               dev_info_once(pmem->bb.dev, "dax is disabled for nfit_test\n");
+               return -EIO;
+       }
+
+       if (unlikely(is_bad_pmem(&pmem->bb, sector, size)))
+               return -EIO;
+       *kaddr = pmem->virt_addr + offset;
+       *pfn = phys_to_pfn_t(pmem->phys_addr + offset, pmem->pfn_flags);
+
+       /*
+        * If badblocks are present, limit known good range to the
+        * requested range.
+        */
+       if (unlikely(pmem->bb.count))
+               return size;
+       return pmem->size - pmem->pfn_pad - offset;
+}

diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index c842095..9966f09 100644 (file)
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -52,7 +52,7 @@ static struct nfit_test_resource *__get_nfit_res(resource_size_t resource)
        return NULL;
 }
 
-static struct nfit_test_resource *get_nfit_res(resource_size_t resource)
+struct nfit_test_resource *get_nfit_res(resource_size_t resource)
 {
        struct nfit_test_resource *res;
 
@@ -62,6 +62,7 @@ static struct nfit_test_resource *get_nfit_res(resource_size_t resource)
 
        return res;
 }
+EXPORT_SYMBOL(get_nfit_res);
 
 void __iomem *__nfit_test_ioremap(resource_size_t offset, unsigned long size,
                void __iomem *(*fallback_fn)(resource_size_t, unsigned long))

diff --git a/tools/testing/nvdimm/test/nfit_test.h b/tools/testing/nvdimm/test/nfit_test.h
index 96c5e16..9f18e2a 100644 (file)
--- a/tools/testing/nvdimm/test/nfit_test.h
+++ b/tools/testing/nvdimm/test/nfit_test.h
@@ -12,6 +12,7 @@
  */
 #ifndef __NFIT_TEST_H__
 #define __NFIT_TEST_H__
+#include <linux/list.h>
 
 struct nfit_test_resource {
        struct list_head list;
@@ -26,4 +27,5 @@ void __iomem *__wrap_ioremap_nocache(resource_size_t offset,
 void __wrap_iounmap(volatile void __iomem *addr);
 void nfit_test_setup(nfit_test_lookup_fn lookup);
 void nfit_test_teardown(void);
+struct nfit_test_resource *get_nfit_res(resource_size_t resource);
 #endif