x86, libnvdimm, pmem: remove global pmem api

Now that all callers of the pmem api have been converted to dax helpers that
call back to the pmem driver, we can remove include/linux/pmem.h and
asm/pmem.h.

Cc: <x86@kernel.org>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Oliver O'Halloran <oohall@gmail.com>
Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

MAINTAINERS

@@ -7592,9 +7592,7 @@ M:	Ross Zwisler <ross.zwisler@linux.intel.com>
 L:	linux-nvdimm@lists.01.org
 Q:	https://patchwork.kernel.org/project/linux-nvdimm/list/
 S:	Supported
-F:	drivers/nvdimm/pmem.c
-F:	include/linux/pmem.h
-F:	arch/*/include/asm/pmem.h
+F:	drivers/nvdimm/pmem*
 
 LIGHTNVM PLATFORM SUPPORT
 M:	Matias Bjorling <mb@lightnvm.io>

arch/x86/include/asm/pmem.h

-/*
- * Copyright(c) 2015 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that 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.
- */
-#ifndef __ASM_X86_PMEM_H__
-#define __ASM_X86_PMEM_H__
-
-#include <linux/uaccess.h>
-#include <asm/cacheflush.h>
-#include <asm/cpufeature.h>
-#include <asm/special_insns.h>
-
-#ifdef CONFIG_ARCH_HAS_PMEM_API
-/**
- * arch_memcpy_to_pmem - copy data to persistent memory
- * @dst: destination buffer for the copy
- * @src: source buffer for the copy
- * @n: length of the copy in bytes
- *
- * Copy data to persistent memory media via non-temporal stores so that
- * a subsequent pmem driver flush operation will drain posted write queues.
- */
-static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n)
-{
-	int rem;
-
-	/*
-	 * We are copying between two kernel buffers, if
-	 * __copy_from_user_inatomic_nocache() returns an error (page
-	 * fault) we would have already reported a general protection fault
-	 * before the WARN+BUG.
-	 */
-	rem = __copy_from_user_inatomic_nocache(dst, (void __user *) src, n);
-	if (WARN(rem, "%s: fault copying %p <- %p unwritten: %d\n",
-				__func__, dst, src, rem))
-		BUG();
-}
-#endif /* CONFIG_ARCH_HAS_PMEM_API */
-#endif /* __ASM_X86_PMEM_H__ */

drivers/acpi/nfit/core.c

@@ -20,7 +20,6 @@
 #include <linux/list.h>
 #include <linux/acpi.h>
 #include <linux/sort.h>
-#include <linux/pmem.h>
 #include <linux/io.h>
 #include <linux/nd.h>
 #include <asm/cacheflush.h>
@@ -1956,7 +1955,7 @@ static int acpi_nfit_blk_region_enable(struct nvdimm_bus *nvdimm_bus,
 	nfit_blk->bdw_offset = nfit_mem->bdw->offset;
 	mmio = &nfit_blk->mmio[BDW];
 	mmio->addr.base = devm_nvdimm_memremap(dev, nfit_mem->spa_bdw->address,
-                        nfit_mem->spa_bdw->length, ARCH_MEMREMAP_PMEM);
+                        nfit_mem->spa_bdw->length, nd_blk_memremap_flags(ndbr));
 	if (!mmio->addr.base) {
 		dev_dbg(dev, "%s: %s failed to map bdw\n", __func__,
 				nvdimm_name(nvdimm));

drivers/nvdimm/claim.c

@@ -12,7 +12,6 @@
  */
 #include <linux/device.h>
 #include <linux/sizes.h>
-#include <linux/pmem.h>
 #include "nd-core.h"
 #include "pmem.h"
 #include "pfn.h"

drivers/nvdimm/dimm_devs.c

@@ -20,6 +20,7 @@
 #include <linux/mm.h>
 #include "nd-core.h"
 #include "label.h"
+#include "pmem.h"
 #include "nd.h"
 
 static DEFINE_IDA(dimm_ida);
@@ -235,6 +236,13 @@ struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
 }
 EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
 
+unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
+{
+	/* pmem mapping properties are private to libnvdimm */
+	return ARCH_MEMREMAP_PMEM;
+}
+EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
+
 struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
 {
 	struct nvdimm *nvdimm = nd_mapping->nvdimm;

drivers/nvdimm/namespace_devs.c

@@ -14,10 +14,10 @@
 #include <linux/device.h>
 #include <linux/sort.h>
 #include <linux/slab.h>
-#include <linux/pmem.h>
 #include <linux/list.h>
 #include <linux/nd.h>
 #include "nd-core.h"
+#include "pmem.h"
 #include "nd.h"
 
 static void namespace_io_release(struct device *dev)
@@ -155,11 +155,7 @@ bool pmem_should_map_pages(struct device *dev)
 				IORES_DESC_NONE) == REGION_MIXED)
 		return false;
 
-#ifdef ARCH_MEMREMAP_PMEM
 	return ARCH_MEMREMAP_PMEM == MEMREMAP_WB;
-#else
-	return false;
-#endif
 }
 EXPORT_SYMBOL(pmem_should_map_pages);
 

drivers/nvdimm/pmem.c

@@ -28,7 +28,6 @@
 #include <linux/blk-mq.h>
 #include <linux/pfn_t.h>
 #include <linux/slab.h>
-#include <linux/pmem.h>
 #include <linux/uio.h>
 #include <linux/dax.h>
 #include <linux/nd.h>

drivers/nvdimm/pmem.h

@@ -6,9 +6,11 @@
 #include <linux/fs.h>
 
 #ifdef CONFIG_ARCH_HAS_PMEM_API
+#define ARCH_MEMREMAP_PMEM MEMREMAP_WB
 void arch_wb_cache_pmem(void *addr, size_t size);
 void arch_invalidate_pmem(void *addr, size_t size);
 #else
+#define ARCH_MEMREMAP_PMEM MEMREMAP_WT
 static inline void arch_wb_cache_pmem(void *addr, size_t size)
 {
 }

drivers/nvdimm/region_devs.c

@@ -15,7 +15,6 @@
 #include <linux/sched.h>
 #include <linux/slab.h>
 #include <linux/hash.h>
-#include <linux/pmem.h>
 #include <linux/sort.h>
 #include <linux/io.h>
 #include <linux/nd.h>

fs/dax.c

@@ -25,7 +25,6 @@
 #include <linux/mm.h>
 #include <linux/mutex.h>
 #include <linux/pagevec.h>
-#include <linux/pmem.h>
 #include <linux/sched.h>
 #include <linux/sched/signal.h>
 #include <linux/uio.h>

include/linux/libnvdimm.h

@@ -159,6 +159,7 @@ void *nd_region_provider_data(struct nd_region *nd_region);
 void *nd_blk_region_provider_data(struct nd_blk_region *ndbr);
 void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data);
 struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr);
+unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr);
 unsigned int nd_region_acquire_lane(struct nd_region *nd_region);
 void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane);
 u64 nd_fletcher64(void *addr, size_t len, bool le);

include/linux/pmem.h

-/*
- * Copyright(c) 2015 Intel Corporation. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of version 2 of the GNU General Public License as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that 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.
- */
-#ifndef __PMEM_H__
-#define __PMEM_H__
-
-#include <linux/io.h>
-#include <linux/uio.h>
-
-#ifdef CONFIG_ARCH_HAS_PMEM_API
-#define ARCH_MEMREMAP_PMEM MEMREMAP_WB
-#include <asm/pmem.h>
-#else
-#define ARCH_MEMREMAP_PMEM MEMREMAP_WT
-/*
- * These are simply here to enable compilation, all call sites gate
- * calling these symbols with arch_has_pmem_api() and redirect to the
- * implementation in asm/pmem.h.
- */
-static inline void arch_memcpy_to_pmem(void *dst, const void *src, size_t n)
-{
-	BUG();
-}
-#endif
-
-static inline bool arch_has_pmem_api(void)
-{
-	return IS_ENABLED(CONFIG_ARCH_HAS_PMEM_API);
-}
-
-/**
- * memcpy_to_pmem - copy data to persistent memory
- * @dst: destination buffer for the copy
- * @src: source buffer for the copy
- * @n: length of the copy in bytes
- *
- * Perform a memory copy that results in the destination of the copy
- * being effectively evicted from, or never written to, the processor
- * cache hierarchy after the copy completes.  After memcpy_to_pmem()
- * data may still reside in cpu or platform buffers, so this operation
- * must be followed by a blkdev_issue_flush() on the pmem block device.
- */
-static inline void memcpy_to_pmem(void *dst, const void *src, size_t n)
-{
-	if (arch_has_pmem_api())
-		arch_memcpy_to_pmem(dst, src, n);
-	else
-		memcpy(dst, src, n);
-}
-#endif /* __PMEM_H__ */