[PATCH v4 00/10] memremap for 4.3

[PATCH v4 00/10] memremap for 4.3

[Dan Williams]

Changes since v3: [1]

1/ Include devm_memremap() support (Christoph)

2/ Rebase the series to defer the removal of ioremap_cache() and drop
   any of the ioremap_cache()-to-memremap() conversions that have yet to be
   acked by the appropriate maintainer. This avoids any potential for
   bisection breakage during the 4.3 merge and the cleanup can be done for
   4.4. (Christoph)

[1]: https://lists.01.org/pipermail/linux-nvdimm/2015-July/001649.html
---

While developing the pmem driver we noticed that the __iomem annotation
on the return value from ioremap_cache() was being mishandled by several
callers.  We also observed that all of the call sites expected to be
able to treat the return value from ioremap_cache() as normal
(non-__iomem) pointer to memory.

See also, the LWN write up: https://lwn.net/Articles/653585/

This has passed a 0day run and will appear in libnvdimm-for-next
shortly.

---

Christoph Hellwig (2):
      devres: add devm_memremap
      pmem: switch to devm_ allocations

Dan Williams (8):
      mm: enhance region_is_ram() to region_intersects()
      arch, drivers: don't include <asm/io.h> directly, use <linux/io.h> instead
      cleanup IORESOURCE_CACHEABLE vs ioremap()
      arch: introduce memremap()
      visorbus: switch from ioremap_cache to memremap
      libnvdimm, pmem: push call to ioremap_cache out of line
      pmem: switch from ioremap_wt to memremap
      pmem: convert to generic memremap


 arch/arm/mach-clps711x/board-cdb89712.c        |    2 
 arch/arm/mach-shmobile/pm-rcar.c               |    2 
 arch/ia64/include/asm/io.h                     |    1 
 arch/ia64/kernel/cyclone.c                     |    2 
 arch/powerpc/kernel/pci_of_scan.c              |    2 
 arch/sh/include/asm/io.h                       |    1 
 arch/sparc/kernel/pci.c                        |    3 -
 arch/x86/include/asm/io.h                      |    7 -
 arch/x86/mm/ioremap.c                          |   10 ++
 arch/xtensa/include/asm/io.h                   |    1 
 drivers/isdn/icn/icn.h                         |    2 
 drivers/mtd/devices/slram.c                    |    2 
 drivers/mtd/nand/diskonchip.c                  |    2 
 drivers/mtd/onenand/generic.c                  |    2 
 drivers/nvdimm/pmem.c                          |   36 ++----
 drivers/pci/probe.c                            |    3 -
 drivers/pnp/manager.c                          |    2 
 drivers/scsi/aic94xx/aic94xx_init.c            |    7 -
 drivers/scsi/arcmsr/arcmsr_hba.c               |    5 -
 drivers/scsi/mvsas/mv_init.c                   |   15 +--
 drivers/scsi/sun3x_esp.c                       |    2 
 drivers/staging/comedi/drivers/ii_pci20kc.c    |    1 
 drivers/staging/unisys/visorbus/visorchannel.c |   16 ++-
 drivers/staging/unisys/visorbus/visorchipset.c |   17 ++-
 drivers/tty/serial/8250/8250_core.c            |    2 
 drivers/video/fbdev/ocfb.c                     |    1 
 drivers/video/fbdev/s1d13xxxfb.c               |    3 -
 drivers/video/fbdev/stifb.c                    |    1 
 include/linux/io-mapping.h                     |    2 
 include/linux/io.h                             |   13 ++
 include/linux/mm.h                             |    9 +-
 include/linux/mtd/map.h                        |    2 
 include/linux/pmem.h                           |   30 +++--
 include/video/vga.h                            |    2 
 kernel/Makefile                                |    2 
 kernel/memremap.c                              |  138 ++++++++++++++++++++++++
 kernel/resource.c                              |   61 ++++++-----
 lib/devres.c                                   |   13 +-
 lib/pci_iomap.c                                |    7 -
 tools/testing/nvdimm/Kbuild                    |    4 -
 tools/testing/nvdimm/test/iomap.c              |   46 ++++++--
 41 files changed, 323 insertions(+), 156 deletions(-)
 create mode 100644 kernel/memremap.c

[PATCH v4 01/10] mm: enhance region_is_ram() to region_intersects()

[Dan Williams]

region_is_ram() is used to prevent the establishment of aliased mappings
to physical "System RAM" with incompatible cache settings.  However, it
uses "-1" to indicate both "unknown" memory ranges (ranges not described
by platform firmware) and "mixed" ranges (where the parameters describe
a range that partially overlaps "System RAM").

Fix this up by explicitly tracking the "unknown" vs "mixed" resource
cases and returning REGION_INTERSECTS, REGION_MIXED, or REGION_DISJOINT.
This re-write also adds support for detecting when the requested region
completely eclipses all of a resource.  Note, the implementation treats
overlaps between "unknown" and the requested memory type as
REGION_INTERSECTS.

Finally, other memory types can be passed in by name, for now the only
usage "System RAM".

Suggested-by: Luis R. Rodriguez <mcgrof@suse.com>
Reviewed-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 include/linux/mm.h |    9 +++++++-
 kernel/resource.c  |   61 +++++++++++++++++++++++++++++++---------------------
 2 files changed, 44 insertions(+), 26 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 2e872f92dbac..84b05ebedb2d 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -369,7 +369,14 @@ static inline int put_page_unless_one(struct page *page)
 }
 
 extern int page_is_ram(unsigned long pfn);
-extern int region_is_ram(resource_size_t phys_addr, unsigned long size);
+
+enum {
+	REGION_INTERSECTS,
+	REGION_DISJOINT,
+	REGION_MIXED,
+};
+
+int region_intersects(resource_size_t offset, size_t size, const char *type);
 
 /* Support for virtually mapped pages */
 struct page *vmalloc_to_page(const void *addr);
diff --git a/kernel/resource.c b/kernel/resource.c
index fed052a1bc9f..f150dbbe6f62 100644
--- a/kernel/resource.c
+++ b/kernel/resource.c
@@ -492,40 +492,51 @@ int __weak page_is_ram(unsigned long pfn)
 }
 EXPORT_SYMBOL_GPL(page_is_ram);
 
-/*
- * Search for a resouce entry that fully contains the specified region.
- * If found, return 1 if it is RAM, 0 if not.
- * If not found, or region is not fully contained, return -1
+/**
+ * region_intersects() - determine intersection of region with known resources
+ * @start: region start address
+ * @size: size of region
+ * @name: name of resource (in iomem_resource)
  *
- * Used by the ioremap functions to ensure the user is not remapping RAM and is
- * a vast speed up over walking through the resource table page by page.
+ * Check if the specified region partially overlaps or fully eclipses a
+ * resource identified by @name.  Return REGION_DISJOINT if the region
+ * does not overlap @name, return REGION_MIXED if the region overlaps
+ * @type and another resource, and return REGION_INTERSECTS if the
+ * region overlaps @type and no other defined resource. Note, that
+ * REGION_INTERSECTS is also returned in the case when the specified
+ * region overlaps RAM and undefined memory holes.
+ *
+ * region_intersect() is used by memory remapping functions to ensure
+ * the user is not remapping RAM and is a vast speed up over walking
+ * through the resource table page by page.
  */
-int region_is_ram(resource_size_t start, unsigned long size)
+int region_intersects(resource_size_t start, size_t size, const char *name)
 {
-	struct resource *p;
-	resource_size_t end = start + size - 1;
 	unsigned long flags = IORESOURCE_MEM | IORESOURCE_BUSY;
-	const char *name = "System RAM";
-	int ret = -1;
+	resource_size_t end = start + size - 1;
+	int type = 0; int other = 0;
+	struct resource *p;
 
 	read_lock(&resource_lock);
 	for (p = iomem_resource.child; p ; p = p->sibling) {
-		if (p->end < start)
-			continue;
-
-		if (p->start <= start && end <= p->end) {
-			/* resource fully contains region */
-			if ((p->flags != flags) || strcmp(p->name, name))
-				ret = 0;
-			else
-				ret = 1;
-			break;
-		}
-		if (end < p->start)
-			break;	/* not found */
+		bool is_type = strcmp(p->name, name) == 0 && p->flags == flags;
+
+		if (start >= p->start && start <= p->end)
+			is_type ? type++ : other++;
+		if (end >= p->start && end <= p->end)
+			is_type ? type++ : other++;
+		if (p->start >= start && p->end <= end)
+			is_type ? type++ : other++;
 	}
 	read_unlock(&resource_lock);
-	return ret;
+
+	if (other == 0)
+		return type ? REGION_INTERSECTS : REGION_DISJOINT;
+
+	if (type)
+		return REGION_MIXED;
+
+	return REGION_DISJOINT;
 }
 
 void __weak arch_remove_reservations(struct resource *avail)

[PATCH v4 02/10] arch, drivers: don't include <asm/io.h> directly, use <linux/io.h> instead

[Dan Williams]

Preparation for uniform definition of ioremap, ioremap_wc, ioremap_wt,
and ioremap_cache, tree-wide.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/arm/mach-shmobile/pm-rcar.c            |    2 +-
 arch/ia64/kernel/cyclone.c                  |    2 +-
 drivers/isdn/icn/icn.h                      |    2 +-
 drivers/mtd/devices/slram.c                 |    2 +-
 drivers/mtd/nand/diskonchip.c               |    2 +-
 drivers/mtd/onenand/generic.c               |    2 +-
 drivers/scsi/sun3x_esp.c                    |    2 +-
 drivers/staging/comedi/drivers/ii_pci20kc.c |    1 +
 drivers/tty/serial/8250/8250_core.c         |    2 +-
 drivers/video/fbdev/s1d13xxxfb.c            |    3 +--
 drivers/video/fbdev/stifb.c                 |    1 +
 include/linux/io-mapping.h                  |    2 +-
 include/linux/mtd/map.h                     |    2 +-
 include/video/vga.h                         |    2 +-
 14 files changed, 14 insertions(+), 13 deletions(-)

diff --git a/arch/arm/mach-shmobile/pm-rcar.c b/arch/arm/mach-shmobile/pm-rcar.c
index 00022ee56f80..9d3dde00c2fe 100644
--- a/arch/arm/mach-shmobile/pm-rcar.c
+++ b/arch/arm/mach-shmobile/pm-rcar.c
@@ -12,7 +12,7 @@
 #include <linux/err.h>
 #include <linux/mm.h>
 #include <linux/spinlock.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include "pm-rcar.h"
 
 /* SYSC */
diff --git a/arch/ia64/kernel/cyclone.c b/arch/ia64/kernel/cyclone.c
index 4826ff957a3d..5fa3848ba224 100644
--- a/arch/ia64/kernel/cyclone.c
+++ b/arch/ia64/kernel/cyclone.c
@@ -4,7 +4,7 @@
 #include <linux/errno.h>
 #include <linux/timex.h>
 #include <linux/clocksource.h>
-#include <asm/io.h>
+#include <linux/io.h>
 
 /* IBM Summit (EXA) Cyclone counter code*/
 #define CYCLONE_CBAR_ADDR 0xFEB00CD0
diff --git a/drivers/isdn/icn/icn.h b/drivers/isdn/icn/icn.h
index b713466997a0..f8f2e76d34bf 100644
--- a/drivers/isdn/icn/icn.h
+++ b/drivers/isdn/icn/icn.h
@@ -38,7 +38,7 @@ typedef struct icn_cdef {
 #include <linux/errno.h>
 #include <linux/fs.h>
 #include <linux/major.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/signal.h>
 #include <linux/slab.h>
diff --git a/drivers/mtd/devices/slram.c b/drivers/mtd/devices/slram.c
index 2fc4957cbe7f..a70eb83e68f1 100644
--- a/drivers/mtd/devices/slram.c
+++ b/drivers/mtd/devices/slram.c
@@ -41,7 +41,7 @@
 #include <linux/fs.h>
 #include <linux/ioctl.h>
 #include <linux/init.h>
-#include <asm/io.h>
+#include <linux/io.h>
 
 #include <linux/mtd/mtd.h>
 
diff --git a/drivers/mtd/nand/diskonchip.c b/drivers/mtd/nand/diskonchip.c
index 7da266a53979..0802158a3f75 100644
--- a/drivers/mtd/nand/diskonchip.c
+++ b/drivers/mtd/nand/diskonchip.c
@@ -24,7 +24,7 @@
 #include <linux/rslib.h>
 #include <linux/moduleparam.h>
 #include <linux/slab.h>
-#include <asm/io.h>
+#include <linux/io.h>
 
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/nand.h>
diff --git a/drivers/mtd/onenand/generic.c b/drivers/mtd/onenand/generic.c
index 32a216d31141..ab7bda0bb245 100644
--- a/drivers/mtd/onenand/generic.c
+++ b/drivers/mtd/onenand/generic.c
@@ -18,7 +18,7 @@
 #include <linux/mtd/mtd.h>
 #include <linux/mtd/onenand.h>
 #include <linux/mtd/partitions.h>
-#include <asm/io.h>
+#include <linux/io.h>
 
 /*
  * Note: Driver name and platform data format have been updated!
diff --git a/drivers/scsi/sun3x_esp.c b/drivers/scsi/sun3x_esp.c
index e26e81de7c45..d50c5ed8f428 100644
--- a/drivers/scsi/sun3x_esp.c
+++ b/drivers/scsi/sun3x_esp.c
@@ -12,9 +12,9 @@
 #include <linux/platform_device.h>
 #include <linux/dma-mapping.h>
 #include <linux/interrupt.h>
+#include <linux/io.h>
 
 #include <asm/sun3x.h>
-#include <asm/io.h>
 #include <asm/dma.h>
 #include <asm/dvma.h>
 
diff --git a/drivers/staging/comedi/drivers/ii_pci20kc.c b/drivers/staging/comedi/drivers/ii_pci20kc.c
index 0768bc42a5db..14ef1f67dd42 100644
--- a/drivers/staging/comedi/drivers/ii_pci20kc.c
+++ b/drivers/staging/comedi/drivers/ii_pci20kc.c
@@ -28,6 +28,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/io.h>
 #include "../comedidev.h"
 
 /*
diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index 37fff12dd4d0..fe902ff52e58 100644
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -38,11 +38,11 @@
 #include <linux/slab.h>
 #include <linux/uaccess.h>
 #include <linux/pm_runtime.h>
+#include <linux/io.h>
 #ifdef CONFIG_SPARC
 #include <linux/sunserialcore.h>
 #endif
 
-#include <asm/io.h>
 #include <asm/irq.h>
 
 #include "8250.h"
diff --git a/drivers/video/fbdev/s1d13xxxfb.c b/drivers/video/fbdev/s1d13xxxfb.c
index 83433cb0dfba..96aa46dc696c 100644
--- a/drivers/video/fbdev/s1d13xxxfb.c
+++ b/drivers/video/fbdev/s1d13xxxfb.c
@@ -32,8 +32,7 @@
 #include <linux/spinlock_types.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
-
-#include <asm/io.h>
+#include <linux/io.h>
 
 #include <video/s1d13xxxfb.h>
 
diff --git a/drivers/video/fbdev/stifb.c b/drivers/video/fbdev/stifb.c
index 735355b0e023..7df4228e25f0 100644
--- a/drivers/video/fbdev/stifb.c
+++ b/drivers/video/fbdev/stifb.c
@@ -64,6 +64,7 @@
 #include <linux/fb.h>
 #include <linux/init.h>
 #include <linux/ioport.h>
+#include <linux/io.h>
 
 #include <asm/grfioctl.h>	/* for HP-UX compatibility */
 #include <asm/uaccess.h>
diff --git a/include/linux/io-mapping.h b/include/linux/io-mapping.h
index c27dde7215b5..e399029b68c5 100644
--- a/include/linux/io-mapping.h
+++ b/include/linux/io-mapping.h
@@ -21,7 +21,7 @@
 #include <linux/types.h>
 #include <linux/slab.h>
 #include <linux/bug.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <asm/page.h>
 
 /*
diff --git a/include/linux/mtd/map.h b/include/linux/mtd/map.h
index 29975c73a953..366cf77953b5 100644
--- a/include/linux/mtd/map.h
+++ b/include/linux/mtd/map.h
@@ -27,9 +27,9 @@
 #include <linux/string.h>
 #include <linux/bug.h>
 #include <linux/kernel.h>
+#include <linux/io.h>
 
 #include <asm/unaligned.h>
-#include <asm/io.h>
 #include <asm/barrier.h>
 
 #ifdef CONFIG_MTD_MAP_BANK_WIDTH_1
diff --git a/include/video/vga.h b/include/video/vga.h
index cac567f22e62..d334e64c1c19 100644
--- a/include/video/vga.h
+++ b/include/video/vga.h
@@ -18,7 +18,7 @@
 #define __linux_video_vga_h__
 
 #include <linux/types.h>
-#include <asm/io.h>
+#include <linux/io.h>
 #include <asm/vga.h>
 #include <asm/byteorder.h>
 

[PATCH v4 03/10] cleanup IORESOURCE_CACHEABLE vs ioremap()

[Dan Williams]

Quoting Arnd:
    I was thinking the opposite approach and basically removing all uses
    of IORESOURCE_CACHEABLE from the kernel. There are only a handful of
    them.and we can probably replace them all with hardcoded
    ioremap_cached() calls in the cases they are actually useful.

All existing usages of IORESOURCE_CACHEABLE call ioremap() instead of
ioremap_nocache() if the resource is cacheable, however ioremap() is
uncached by default. Clearly none of the existing usages care about the
cacheability. Particularly devm_ioremap_resource() never worked as
advertised since it always fell back to plain ioremap().

Clean this up as the new direction we want is to convert
ioremap_<type>() usages to memremap(..., flags).

Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/arm/mach-clps711x/board-cdb89712.c |    2 +-
 arch/powerpc/kernel/pci_of_scan.c       |    2 +-
 arch/sparc/kernel/pci.c                 |    3 +--
 drivers/pci/probe.c                     |    3 +--
 drivers/pnp/manager.c                   |    2 --
 drivers/scsi/aic94xx/aic94xx_init.c     |    7 +------
 drivers/scsi/arcmsr/arcmsr_hba.c        |    5 +----
 drivers/scsi/mvsas/mv_init.c            |   15 ++++-----------
 drivers/video/fbdev/ocfb.c              |    1 -
 lib/devres.c                            |   13 ++++---------
 lib/pci_iomap.c                         |    7 ++-----
 11 files changed, 16 insertions(+), 44 deletions(-)

diff --git a/arch/arm/mach-clps711x/board-cdb89712.c b/arch/arm/mach-clps711x/board-cdb89712.c
index 1ec378c334e5..972abdb10028 100644
--- a/arch/arm/mach-clps711x/board-cdb89712.c
+++ b/arch/arm/mach-clps711x/board-cdb89712.c
@@ -95,7 +95,7 @@ static struct physmap_flash_data cdb89712_bootrom_pdata __initdata = {
 
 static struct resource cdb89712_bootrom_resources[] __initdata = {
 	DEFINE_RES_NAMED(CS7_PHYS_BASE, SZ_128, "BOOTROM", IORESOURCE_MEM |
-			 IORESOURCE_CACHEABLE | IORESOURCE_READONLY),
+			 IORESOURCE_READONLY),
 };
 
 static struct platform_device cdb89712_bootrom_pdev __initdata = {
diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c
index 42e02a2d570b..d4726addff0b 100644
--- a/arch/powerpc/kernel/pci_of_scan.c
+++ b/arch/powerpc/kernel/pci_of_scan.c
@@ -102,7 +102,7 @@ static void of_pci_parse_addrs(struct device_node *node, struct pci_dev *dev)
 			res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
 		} else if (i == dev->rom_base_reg) {
 			res = &dev->resource[PCI_ROM_RESOURCE];
-			flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE;
+			flags |= IORESOURCE_READONLY;
 		} else {
 			printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
 			continue;
diff --git a/arch/sparc/kernel/pci.c b/arch/sparc/kernel/pci.c
index c928bc64b4ba..04da147e0712 100644
--- a/arch/sparc/kernel/pci.c
+++ b/arch/sparc/kernel/pci.c
@@ -231,8 +231,7 @@ static void pci_parse_of_addrs(struct platform_device *op,
 			res = &dev->resource[(i - PCI_BASE_ADDRESS_0) >> 2];
 		} else if (i == dev->rom_base_reg) {
 			res = &dev->resource[PCI_ROM_RESOURCE];
-			flags |= IORESOURCE_READONLY | IORESOURCE_CACHEABLE
-			      | IORESOURCE_SIZEALIGN;
+			flags |= IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
 		} else {
 			printk(KERN_ERR "PCI: bad cfg reg num 0x%x\n", i);
 			continue;
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index cefd636681b6..8ed37dd04056 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -326,8 +326,7 @@ static void pci_read_bases(struct pci_dev *dev, unsigned int howmany, int rom)
 		struct resource *res = &dev->resource[PCI_ROM_RESOURCE];
 		dev->rom_base_reg = rom;
 		res->flags = IORESOURCE_MEM | IORESOURCE_PREFETCH |
-				IORESOURCE_READONLY | IORESOURCE_CACHEABLE |
-				IORESOURCE_SIZEALIGN;
+				IORESOURCE_READONLY | IORESOURCE_SIZEALIGN;
 		__pci_read_base(dev, pci_bar_mem32, res, rom);
 	}
 }
diff --git a/drivers/pnp/manager.c b/drivers/pnp/manager.c
index 9357aa779048..7ad3295752ef 100644
--- a/drivers/pnp/manager.c
+++ b/drivers/pnp/manager.c
@@ -97,8 +97,6 @@ static int pnp_assign_mem(struct pnp_dev *dev, struct pnp_mem *rule, int idx)
 	/* ??? rule->flags restricted to 8 bits, all tests bogus ??? */
 	if (!(rule->flags & IORESOURCE_MEM_WRITEABLE))
 		res->flags |= IORESOURCE_READONLY;
-	if (rule->flags & IORESOURCE_MEM_CACHEABLE)
-		res->flags |= IORESOURCE_CACHEABLE;
 	if (rule->flags & IORESOURCE_MEM_RANGELENGTH)
 		res->flags |= IORESOURCE_RANGELENGTH;
 	if (rule->flags & IORESOURCE_MEM_SHADOWABLE)
diff --git a/drivers/scsi/aic94xx/aic94xx_init.c b/drivers/scsi/aic94xx/aic94xx_init.c
index 4b135cca42a1..140cb8e6fea2 100644
--- a/drivers/scsi/aic94xx/aic94xx_init.c
+++ b/drivers/scsi/aic94xx/aic94xx_init.c
@@ -100,12 +100,7 @@ static int asd_map_memio(struct asd_ha_struct *asd_ha)
 				   pci_name(asd_ha->pcidev));
 			goto Err;
 		}
-		if (io_handle->flags & IORESOURCE_CACHEABLE)
-			io_handle->addr = ioremap(io_handle->start,
-						  io_handle->len);
-		else
-			io_handle->addr = ioremap_nocache(io_handle->start,
-							  io_handle->len);
+		io_handle->addr = ioremap(io_handle->start, io_handle->len);
 		if (!io_handle->addr) {
 			asd_printk("couldn't map MBAR%d of %s\n", i==0?0:1,
 				   pci_name(asd_ha->pcidev));
diff --git a/drivers/scsi/arcmsr/arcmsr_hba.c b/drivers/scsi/arcmsr/arcmsr_hba.c
index 914c39f9f388..e4f77cad9fd8 100644
--- a/drivers/scsi/arcmsr/arcmsr_hba.c
+++ b/drivers/scsi/arcmsr/arcmsr_hba.c
@@ -259,10 +259,7 @@ static bool arcmsr_remap_pciregion(struct AdapterControlBlock *acb)
 		addr = (unsigned long)pci_resource_start(pdev, 0);
 		range = pci_resource_len(pdev, 0);
 		flags = pci_resource_flags(pdev, 0);
-		if (flags & IORESOURCE_CACHEABLE)
-			mem_base0 = ioremap(addr, range);
-		else
-			mem_base0 = ioremap_nocache(addr, range);
+		mem_base0 = ioremap(addr, range);
 		if (!mem_base0) {
 			pr_notice("arcmsr%d: memory mapping region fail\n",
 				acb->host->host_no);
diff --git a/drivers/scsi/mvsas/mv_init.c b/drivers/scsi/mvsas/mv_init.c
index d40d734aa53a..e654b5cec69e 100644
--- a/drivers/scsi/mvsas/mv_init.c
+++ b/drivers/scsi/mvsas/mv_init.c
@@ -324,13 +324,9 @@ int mvs_ioremap(struct mvs_info *mvi, int bar, int bar_ex)
 			goto err_out;
 
 		res_flag_ex = pci_resource_flags(pdev, bar_ex);
-		if (res_flag_ex & IORESOURCE_MEM) {
-			if (res_flag_ex & IORESOURCE_CACHEABLE)
-				mvi->regs_ex = ioremap(res_start, res_len);
-			else
-				mvi->regs_ex = ioremap_nocache(res_start,
-						res_len);
-		} else
+		if (res_flag_ex & IORESOURCE_MEM)
+			mvi->regs_ex = ioremap(res_start, res_len);
+		else
 			mvi->regs_ex = (void *)res_start;
 		if (!mvi->regs_ex)
 			goto err_out;
@@ -342,10 +338,7 @@ int mvs_ioremap(struct mvs_info *mvi, int bar, int bar_ex)
 		goto err_out;
 
 	res_flag = pci_resource_flags(pdev, bar);
-	if (res_flag & IORESOURCE_CACHEABLE)
-		mvi->regs = ioremap(res_start, res_len);
-	else
-		mvi->regs = ioremap_nocache(res_start, res_len);
+	mvi->regs = ioremap(res_start, res_len);
 
 	if (!mvi->regs) {
 		if (mvi->regs_ex && (res_flag_ex & IORESOURCE_MEM))
diff --git a/drivers/video/fbdev/ocfb.c b/drivers/video/fbdev/ocfb.c
index de9819660ca0..c9293aea8ec3 100644
--- a/drivers/video/fbdev/ocfb.c
+++ b/drivers/video/fbdev/ocfb.c
@@ -325,7 +325,6 @@ static int ocfb_probe(struct platform_device *pdev)
 		dev_err(&pdev->dev, "I/O resource request failed\n");
 		return -ENXIO;
 	}
-	res->flags &= ~IORESOURCE_CACHEABLE;
 	fbdev->regs = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(fbdev->regs))
 		return PTR_ERR(fbdev->regs);
diff --git a/lib/devres.c b/lib/devres.c
index fbe2aac522e6..f13a2468ff39 100644
--- a/lib/devres.c
+++ b/lib/devres.c
@@ -119,10 +119,9 @@ EXPORT_SYMBOL(devm_iounmap);
  * @dev: generic device to handle the resource for
  * @res: resource to be handled
  *
- * Checks that a resource is a valid memory region, requests the memory region
- * and ioremaps it either as cacheable or as non-cacheable memory depending on
- * the resource's flags. All operations are managed and will be undone on
- * driver detach.
+ * Checks that a resource is a valid memory region, requests the memory
+ * region and ioremaps it. All operations are managed and will be undone
+ * on driver detach.
  *
  * Returns a pointer to the remapped memory or an ERR_PTR() encoded error code
  * on failure. Usage example:
@@ -153,11 +152,7 @@ void __iomem *devm_ioremap_resource(struct device *dev, struct resource *res)
 		return IOMEM_ERR_PTR(-EBUSY);
 	}
 
-	if (res->flags & IORESOURCE_CACHEABLE)
-		dest_ptr = devm_ioremap(dev, res->start, size);
-	else
-		dest_ptr = devm_ioremap_nocache(dev, res->start, size);
-
+	dest_ptr = devm_ioremap(dev, res->start, size);
 	if (!dest_ptr) {
 		dev_err(dev, "ioremap failed for resource %pR\n", res);
 		devm_release_mem_region(dev, res->start, size);
diff --git a/lib/pci_iomap.c b/lib/pci_iomap.c
index bcce5f149310..e1930dbab2da 100644
--- a/lib/pci_iomap.c
+++ b/lib/pci_iomap.c
@@ -41,11 +41,8 @@ void __iomem *pci_iomap_range(struct pci_dev *dev,
 		len = maxlen;
 	if (flags & IORESOURCE_IO)
 		return __pci_ioport_map(dev, start, len);
-	if (flags & IORESOURCE_MEM) {
-		if (flags & IORESOURCE_CACHEABLE)
-			return ioremap(start, len);
-		return ioremap_nocache(start, len);
-	}
+	if (flags & IORESOURCE_MEM)
+		return ioremap(start, len);
 	/* What? */
 	return NULL;
 }

[PATCH v4 04/10] arch: introduce memremap()

[Dan Williams]

Existing users of ioremap_cache() are mapping memory that is known in
advance to not have i/o side effects.  These users are forced to cast
away the __iomem annotation, or otherwise neglect to fix the sparse
errors thrown when dereferencing pointers to this memory.  Provide
memremap() as a non __iomem annotated ioremap_*() in the case when
ioremap is otherwise a pointer to cacheable memory. Empirically,
ioremap_<cacheable-type>() call sites are seeking memory-like semantics
(e.g.  speculative reads, and prefetching permitted).

memremap() is a break from the ioremap implementation pattern of adding
a new memremap_<type>() for each mapping type and having silent
compatibility fall backs.  Instead, the implementation defines flags
that are passed to the central memremap() and if a mapping type is not
supported by an arch memremap returns NULL.

We introduce a memremap prototype as a trivial wrapper of
ioremap_cache() and ioremap_wt().  Later, once all ioremap_cache() and
ioremap_wt() usage has been removed from drivers we teach archs to
implement arch_memremap() with the ability to strictly enforce the
mapping type.

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/ia64/include/asm/io.h   |    1 
 arch/sh/include/asm/io.h     |    1 
 arch/xtensa/include/asm/io.h |    1 
 include/linux/io.h           |    9 ++++
 kernel/Makefile              |    2 +
 kernel/memremap.c            |   98 ++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 112 insertions(+)
 create mode 100644 kernel/memremap.c

diff --git a/arch/ia64/include/asm/io.h b/arch/ia64/include/asm/io.h
index 80a7e34be009..9041bbe2b7b4 100644
--- a/arch/ia64/include/asm/io.h
+++ b/arch/ia64/include/asm/io.h
@@ -435,6 +435,7 @@ static inline void __iomem * ioremap_cache (unsigned long phys_addr, unsigned lo
 {
 	return ioremap(phys_addr, size);
 }
+#define ioremap_cache ioremap_cache
 
 
 /*
diff --git a/arch/sh/include/asm/io.h b/arch/sh/include/asm/io.h
index 728c4c571f40..6194e20fccca 100644
--- a/arch/sh/include/asm/io.h
+++ b/arch/sh/include/asm/io.h
@@ -342,6 +342,7 @@ ioremap_cache(phys_addr_t offset, unsigned long size)
 {
 	return __ioremap_mode(offset, size, PAGE_KERNEL);
 }
+#define ioremap_cache ioremap_cache
 
 #ifdef CONFIG_HAVE_IOREMAP_PROT
 static inline void __iomem *
diff --git a/arch/xtensa/include/asm/io.h b/arch/xtensa/include/asm/io.h
index c39bb6e61911..867840f5400f 100644
--- a/arch/xtensa/include/asm/io.h
+++ b/arch/xtensa/include/asm/io.h
@@ -57,6 +57,7 @@ static inline void __iomem *ioremap_cache(unsigned long offset,
 	else
 		BUG();
 }
+#define ioremap_cache ioremap_cache
 
 #define ioremap_wc ioremap_nocache
 #define ioremap_wt ioremap_nocache
diff --git a/include/linux/io.h b/include/linux/io.h
index fb5a99800e77..3fcf6256c088 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -121,4 +121,13 @@ static inline int arch_phys_wc_index(int handle)
 #endif
 #endif
 
+enum {
+	/* See memremap() kernel-doc for usage description... */
+	MEMREMAP_WB = 1 << 0,
+	MEMREMAP_WT = 1 << 1,
+};
+
+void *memremap(resource_size_t offset, size_t size, unsigned long flags);
+void memunmap(void *addr);
+
 #endif /* _LINUX_IO_H */
diff --git a/kernel/Makefile b/kernel/Makefile
index 43c4c920f30a..92866d36e376 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -99,6 +99,8 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
 obj-$(CONFIG_CONTEXT_TRACKING) += context_tracking.o
 obj-$(CONFIG_TORTURE_TEST) += torture.o
 
+obj-$(CONFIG_HAS_IOMEM) += memremap.o
+
 $(obj)/configs.o: $(obj)/config_data.h
 
 # config_data.h contains the same information as ikconfig.h but gzipped.
diff --git a/kernel/memremap.c b/kernel/memremap.c
new file mode 100644
index 000000000000..a293de52e837
--- /dev/null
+++ b/kernel/memremap.c
@@ -0,0 +1,98 @@
+/*
+ * 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.
+ */
+#include <linux/types.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+
+#ifndef ioremap_cache
+/* temporary while we convert existing ioremap_cache users to memremap */
+__weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size)
+{
+	return ioremap(offset, size);
+}
+#endif
+
+/**
+ * memremap() - remap an iomem_resource as cacheable memory
+ * @offset: iomem resource start address
+ * @size: size of remap
+ * @flags: either MEMREMAP_WB or MEMREMAP_WT
+ *
+ * memremap() is "ioremap" for cases where it is known that the resource
+ * being mapped does not have i/o side effects and the __iomem
+ * annotation is not applicable.
+ *
+ * MEMREMAP_WB - matches the default mapping for "System RAM" on
+ * the architecture.  This is usually a read-allocate write-back cache.
+ * Morever, if MEMREMAP_WB is specified and the requested remap region is RAM
+ * memremap() will bypass establishing a new mapping and instead return
+ * a pointer into the direct map.
+ *
+ * MEMREMAP_WT - establish a mapping whereby writes either bypass the
+ * cache or are written through to memory and never exist in a
+ * cache-dirty state with respect to program visibility.  Attempts to
+ * map "System RAM" with this mapping type will fail.
+ */
+void *memremap(resource_size_t offset, size_t size, unsigned long flags)
+{
+	int is_ram = region_intersects(offset, size, "System RAM");
+	void *addr = NULL;
+
+	if (is_ram == REGION_MIXED) {
+		WARN_ONCE(1, "memremap attempted on mixed range %pa size: %#lx\n",
+				&offset, (unsigned long) size);
+		return NULL;
+	}
+
+	/* Try all mapping types requested until one returns non-NULL */
+	if (flags & MEMREMAP_WB) {
+		flags &= ~MEMREMAP_WB;
+		/*
+		 * MEMREMAP_WB is special in that it can be satisifed
+		 * from the direct map.  Some archs depend on the
+		 * capability of memremap() to autodetect cases where
+		 * the requested range is potentially in "System RAM"
+		 */
+		if (is_ram == REGION_INTERSECTS)
+			addr = __va(offset);
+		else
+			addr = ioremap_cache(offset, size);
+	}
+
+	/*
+	 * If we don't have a mapping yet and more request flags are
+	 * pending then we will be attempting to establish a new virtual
+	 * address mapping.  Enforce that this mapping is not aliasing
+	 * "System RAM"
+	 */
+	if (!addr && is_ram == REGION_INTERSECTS && flags) {
+		WARN_ONCE(1, "memremap attempted on ram %pa size: %#lx\n",
+				&offset, (unsigned long) size);
+		return NULL;
+	}
+
+	if (!addr && (flags & MEMREMAP_WT)) {
+		flags &= ~MEMREMAP_WT;
+		addr = ioremap_wt(offset, size);
+	}
+
+	return addr;
+}
+EXPORT_SYMBOL(memremap);
+
+void memunmap(void *addr)
+{
+	if (is_vmalloc_addr(addr))
+		iounmap((void __iomem *) addr);
+}
+EXPORT_SYMBOL(memunmap);

[PATCH v4 05/10] visorbus: switch from ioremap_cache to memremap

[Dan Williams]

In preparation for deprecating ioremap_cache() convert its usage in
visorbus to memremap.

Cc: Benjamin Romer <benjamin.romer@unisys.com>
Cc: David Kershner <david.kershner@unisys.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/staging/unisys/visorbus/visorchannel.c |   16 +++++++++-------
 drivers/staging/unisys/visorbus/visorchipset.c |   17 +++++++++--------
 2 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/drivers/staging/unisys/visorbus/visorchannel.c b/drivers/staging/unisys/visorbus/visorchannel.c
index 20b63496e9f2..19c4a78a3617 100644
--- a/drivers/staging/unisys/visorbus/visorchannel.c
+++ b/drivers/staging/unisys/visorbus/visorchannel.c
@@ -21,6 +21,7 @@
  */
 
 #include <linux/uuid.h>
+#include <linux/io.h>
 
 #include "version.h"
 #include "visorbus.h"
@@ -36,7 +37,7 @@ static const uuid_le spar_video_guid = SPAR_CONSOLEVIDEO_CHANNEL_PROTOCOL_GUID;
 struct visorchannel {
 	u64 physaddr;
 	ulong nbytes;
-	void __iomem *mapped;
+	void *mapped;
 	bool requested;
 	struct channel_header chan_hdr;
 	uuid_le guid;
@@ -93,7 +94,7 @@ visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes,
 		}
 	}
 
-	channel->mapped = ioremap_cache(physaddr, size);
+	channel->mapped = memremap(physaddr, size, MEMREMAP_WB);
 	if (!channel->mapped) {
 		release_mem_region(physaddr, size);
 		goto cleanup;
@@ -113,7 +114,7 @@ visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes,
 	if (uuid_le_cmp(guid, NULL_UUID_LE) == 0)
 		guid = channel->chan_hdr.chtype;
 
-	iounmap(channel->mapped);
+	memunmap(channel->mapped);
 	if (channel->requested)
 		release_mem_region(channel->physaddr, channel->nbytes);
 	channel->mapped = NULL;
@@ -126,7 +127,8 @@ visorchannel_create_guts(u64 physaddr, unsigned long channel_bytes,
 		}
 	}
 
-	channel->mapped = ioremap_cache(channel->physaddr, channel_bytes);
+	channel->mapped = memremap(channel->physaddr, channel_bytes,
+			MEMREMAP_WB);
 	if (!channel->mapped) {
 		release_mem_region(channel->physaddr, channel_bytes);
 		goto cleanup;
@@ -167,7 +169,7 @@ visorchannel_destroy(struct visorchannel *channel)
 	if (!channel)
 		return;
 	if (channel->mapped) {
-		iounmap(channel->mapped);
+		memunmap(channel->mapped);
 		if (channel->requested)
 			release_mem_region(channel->physaddr, channel->nbytes);
 	}
@@ -241,7 +243,7 @@ visorchannel_read(struct visorchannel *channel, ulong offset,
 	if (offset + nbytes > channel->nbytes)
 		return -EIO;
 
-	memcpy_fromio(local, channel->mapped + offset, nbytes);
+	memcpy(local, channel->mapped + offset, nbytes);
 
 	return 0;
 }
@@ -262,7 +264,7 @@ visorchannel_write(struct visorchannel *channel, ulong offset,
 		memcpy(&channel->chan_hdr + offset, local, copy_size);
 	}
 
-	memcpy_toio(channel->mapped + offset, local, nbytes);
+	memcpy(channel->mapped + offset, local, nbytes);
 
 	return 0;
 }
diff --git a/drivers/staging/unisys/visorbus/visorchipset.c b/drivers/staging/unisys/visorbus/visorchipset.c
index bb8087e70127..e3c55ccf929b 100644
--- a/drivers/staging/unisys/visorbus/visorchipset.c
+++ b/drivers/staging/unisys/visorbus/visorchipset.c
@@ -119,7 +119,7 @@ static struct visorchannel *controlvm_channel;
 
 /* Manages the request payload in the controlvm channel */
 struct visor_controlvm_payload_info {
-	u8 __iomem *ptr;	/* pointer to base address of payload pool */
+	u8 *ptr;		/* pointer to base address of payload pool */
 	u64 offset;		/* offset from beginning of controlvm
 				 * channel to beginning of payload * pool */
 	u32 bytes;		/* number of bytes in payload pool */
@@ -401,21 +401,22 @@ parser_init_byte_stream(u64 addr, u32 bytes, bool local, bool *retry)
 		p = __va((unsigned long) (addr));
 		memcpy(ctx->data, p, bytes);
 	} else {
-		void __iomem *mapping;
+		void *mapping;
 
 		if (!request_mem_region(addr, bytes, "visorchipset")) {
 			rc = NULL;
 			goto cleanup;
 		}
 
-		mapping = ioremap_cache(addr, bytes);
+		mapping = memremap(addr, bytes, MEMREMAP_WB);
 		if (!mapping) {
 			release_mem_region(addr, bytes);
 			rc = NULL;
 			goto cleanup;
 		}
-		memcpy_fromio(ctx->data, mapping, bytes);
+		memcpy(ctx->data, mapping, bytes);
 		release_mem_region(addr, bytes);
+		memunmap(mapping);
 	}
 
 	ctx->byte_stream = true;
@@ -1327,7 +1328,7 @@ static int
 initialize_controlvm_payload_info(u64 phys_addr, u64 offset, u32 bytes,
 				  struct visor_controlvm_payload_info *info)
 {
-	u8 __iomem *payload = NULL;
+	u8 *payload = NULL;
 	int rc = CONTROLVM_RESP_SUCCESS;
 
 	if (!info) {
@@ -1339,7 +1340,7 @@ initialize_controlvm_payload_info(u64 phys_addr, u64 offset, u32 bytes,
 		rc = -CONTROLVM_RESP_ERROR_PAYLOAD_INVALID;
 		goto cleanup;
 	}
-	payload = ioremap_cache(phys_addr + offset, bytes);
+	payload = memremap(phys_addr + offset, bytes, MEMREMAP_WB);
 	if (!payload) {
 		rc = -CONTROLVM_RESP_ERROR_IOREMAP_FAILED;
 		goto cleanup;
@@ -1352,7 +1353,7 @@ initialize_controlvm_payload_info(u64 phys_addr, u64 offset, u32 bytes,
 cleanup:
 	if (rc < 0) {
 		if (payload) {
-			iounmap(payload);
+			memunmap(payload);
 			payload = NULL;
 		}
 	}
@@ -1363,7 +1364,7 @@ static void
 destroy_controlvm_payload_info(struct visor_controlvm_payload_info *info)
 {
 	if (info->ptr) {
-		iounmap(info->ptr);
+		memunmap(info->ptr);
 		info->ptr = NULL;
 	}
 	memset(info, 0, sizeof(struct visor_controlvm_payload_info));

[PATCH v4 06/10] libnvdimm, pmem: push call to ioremap_cache out of line

[Dan Williams]

In preparation for deprecating ioremap_cache() push its usage into arch
code where it deleted in a later globabl conversion of ioremap_cache()
to arch_memremap().

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/x86/include/asm/io.h         |    7 +------
 arch/x86/mm/ioremap.c             |    6 ++++++
 tools/testing/nvdimm/Kbuild       |    2 +-
 tools/testing/nvdimm/test/iomap.c |    6 +++---
 4 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index cc9c61bc1abe..8aeb6456188a 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -248,12 +248,7 @@ static inline void flush_write_buffers(void)
 #endif
 }
 
-static inline void __pmem *arch_memremap_pmem(resource_size_t offset,
-	unsigned long size)
-{
-	return (void __force __pmem *) ioremap_cache(offset, size);
-}
-
+void __pmem *arch_memremap_pmem(resource_size_t offset, size_t size);
 #endif /* __KERNEL__ */
 
 extern void native_io_delay(void);
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index b9c78f3bcd67..c0734030e9db 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -317,6 +317,12 @@ void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
 }
 EXPORT_SYMBOL(ioremap_cache);
 
+void __pmem *arch_memremap_pmem(resource_size_t offset, size_t size)
+{
+	return (void __force __pmem *) ioremap_cache(offset, size);
+}
+EXPORT_SYMBOL(arch_memremap_pmem);
+
 void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
 				unsigned long prot_val)
 {
diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index f56914c7929b..de2912ea78e8 100644
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -1,7 +1,7 @@
 ldflags-y += --wrap=ioremap_wt
 ldflags-y += --wrap=ioremap_wc
 ldflags-y += --wrap=devm_ioremap_nocache
-ldflags-y += --wrap=ioremap_cache
+ldflags-y += --wrap=arch_memremap_pmem
 ldflags-y += --wrap=ioremap_nocache
 ldflags-y += --wrap=iounmap
 ldflags-y += --wrap=__request_region
diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index 64bfaa50831c..f8486f98f860 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -80,11 +80,11 @@ void __iomem *__wrap_devm_ioremap_nocache(struct device *dev,
 }
 EXPORT_SYMBOL(__wrap_devm_ioremap_nocache);
 
-void __iomem *__wrap_ioremap_cache(resource_size_t offset, unsigned long size)
+void *__wrap_arch_memremap_pmem(resource_size_t offset, size_t size)
 {
-	return __nfit_test_ioremap(offset, size, ioremap_cache);
+	return __nfit_test_ioremap(offset, size, arch_memremap_pmem);
 }
-EXPORT_SYMBOL(__wrap_ioremap_cache);
+EXPORT_SYMBOL(__wrap_arch_memremap_pmem);
 
 void __iomem *__wrap_ioremap_nocache(resource_size_t offset, unsigned long size)
 {

[PATCH v4 07/10] pmem: switch from ioremap_wt to memremap

[Dan Williams]

In preparation for deprecating ioremap_wt() convert its usage in
the PMEM API to memremap.

Acked-by: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 include/linux/pmem.h              |    2 +-
 tools/testing/nvdimm/Kbuild       |    4 ++--
 tools/testing/nvdimm/test/iomap.c |   34 +++++++++++++++++++++++++---------
 3 files changed, 28 insertions(+), 12 deletions(-)

diff --git a/include/linux/pmem.h b/include/linux/pmem.h
index d2114045a6c4..1bf74c735fa0 100644
--- a/include/linux/pmem.h
+++ b/include/linux/pmem.h
@@ -94,7 +94,7 @@ static void default_memcpy_to_pmem(void __pmem *dst, const void *src,
 static void __pmem *default_memremap_pmem(resource_size_t offset,
 		unsigned long size)
 {
-	return (void __pmem __force *)ioremap_wt(offset, size);
+	return (void __pmem *) memremap(offset, size, MEMREMAP_WT);
 }
 
 /**
diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index de2912ea78e8..8032a49f7873 100644
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -1,7 +1,7 @@
-ldflags-y += --wrap=ioremap_wt
 ldflags-y += --wrap=ioremap_wc
 ldflags-y += --wrap=devm_ioremap_nocache
-ldflags-y += --wrap=arch_memremap_pmem
+ldflags-y += --wrap=memremap
+ldflags-y += --wrap=memunmap
 ldflags-y += --wrap=ioremap_nocache
 ldflags-y += --wrap=iounmap
 ldflags-y += --wrap=__request_region
diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index f8486f98f860..21288f34a5ca 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -80,11 +80,20 @@ void __iomem *__wrap_devm_ioremap_nocache(struct device *dev,
 }
 EXPORT_SYMBOL(__wrap_devm_ioremap_nocache);
 
-void *__wrap_arch_memremap_pmem(resource_size_t offset, size_t size)
+void *__wrap_memremap(resource_size_t offset, size_t size,
+		unsigned long flags)
 {
-	return __nfit_test_ioremap(offset, size, arch_memremap_pmem);
+	struct nfit_test_resource *nfit_res;
+
+	rcu_read_lock();
+	nfit_res = get_nfit_res(offset);
+	rcu_read_unlock();
+	if (nfit_res)
+		return (void __iomem *) nfit_res->buf + offset
+			- nfit_res->res->start;
+	return memremap(offset, size, flags);
 }
-EXPORT_SYMBOL(__wrap_arch_memremap_pmem);
+EXPORT_SYMBOL(__wrap_memremap);
 
 void __iomem *__wrap_ioremap_nocache(resource_size_t offset, unsigned long size)
 {
@@ -92,12 +101,6 @@ void __iomem *__wrap_ioremap_nocache(resource_size_t offset, unsigned long size)
 }
 EXPORT_SYMBOL(__wrap_ioremap_nocache);
 
-void __iomem *__wrap_ioremap_wt(resource_size_t offset, unsigned long size)
-{
-	return __nfit_test_ioremap(offset, size, ioremap_wt);
-}
-EXPORT_SYMBOL(__wrap_ioremap_wt);
-
 void __iomem *__wrap_ioremap_wc(resource_size_t offset, unsigned long size)
 {
 	return __nfit_test_ioremap(offset, size, ioremap_wc);
@@ -117,6 +120,19 @@ void __wrap_iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(__wrap_iounmap);
 
+void __wrap_memunmap(void *addr)
+{
+	struct nfit_test_resource *nfit_res;
+
+	rcu_read_lock();
+	nfit_res = get_nfit_res((unsigned long) addr);
+	rcu_read_unlock();
+	if (nfit_res)
+		return;
+	return memunmap(addr);
+}
+EXPORT_SYMBOL(__wrap_memunmap);
+
 struct resource *__wrap___request_region(struct resource *parent,
 		resource_size_t start, resource_size_t n, const char *name,
 		int flags)

[PATCH v4 08/10] pmem: convert to generic memremap

[Dan Williams]

Update memremap_pmem() to query the architecture for the mapping type of
the given persistent memory range  and then pass those flags to generic
memremap().  arch_memremap_pmem_flags() is provided an address range to
evaluate in the event an arch has a need for different mapping types by
address range.  For example the ACPI NFIT carries EFI mapping types in
its memory range description table.

Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 arch/x86/include/asm/io.h |    2 +-
 arch/x86/mm/ioremap.c     |   16 ++++++++++------
 include/linux/pmem.h      |   26 +++++++++++++++-----------
 3 files changed, 26 insertions(+), 18 deletions(-)

diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h
index 8aeb6456188a..1644e19ea032 100644
--- a/arch/x86/include/asm/io.h
+++ b/arch/x86/include/asm/io.h
@@ -248,7 +248,7 @@ static inline void flush_write_buffers(void)
 #endif
 }
 
-void __pmem *arch_memremap_pmem(resource_size_t offset, size_t size);
+unsigned long arch_memremap_pmem_flags(resource_size_t offset, size_t size);
 #endif /* __KERNEL__ */
 
 extern void native_io_delay(void);
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index c0734030e9db..43b12c146113 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -205,6 +205,16 @@ err_free_memtype:
 	return NULL;
 }
 
+unsigned long arch_memremap_pmem_flags(resource_size_t offset, size_t size)
+{
+	/*
+	 * The expectation is that pmem is always WB capable range on
+	 * x86, i.e. no need to walk the range.
+	 */
+	return MEMREMAP_WB;
+}
+EXPORT_SYMBOL(arch_memremap_pmem_flags);
+
 /**
  * ioremap_nocache     -   map bus memory into CPU space
  * @phys_addr:    bus address of the memory
@@ -317,12 +327,6 @@ void __iomem *ioremap_cache(resource_size_t phys_addr, unsigned long size)
 }
 EXPORT_SYMBOL(ioremap_cache);
 
-void __pmem *arch_memremap_pmem(resource_size_t offset, size_t size)
-{
-	return (void __force __pmem *) ioremap_cache(offset, size);
-}
-EXPORT_SYMBOL(arch_memremap_pmem);
-
 void __iomem *ioremap_prot(resource_size_t phys_addr, unsigned long size,
 				unsigned long prot_val)
 {
diff --git a/include/linux/pmem.h b/include/linux/pmem.h
index 1bf74c735fa0..03f9d73f3e13 100644
--- a/include/linux/pmem.h
+++ b/include/linux/pmem.h
@@ -28,10 +28,10 @@ static inline bool __arch_has_wmb_pmem(void)
 	return false;
 }
 
-static inline void __pmem *arch_memremap_pmem(resource_size_t offset,
+static inline unsigned long arch_memremap_pmem_flags(resource_size_t offset,
 		unsigned long size)
 {
-	return NULL;
+	return 0;
 }
 
 static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
@@ -43,8 +43,8 @@ static inline void arch_memcpy_to_pmem(void __pmem *dst, const void *src,
 
 /*
  * Architectures that define ARCH_HAS_PMEM_API must provide
- * implementations for arch_memremap_pmem(), arch_memcpy_to_pmem(),
- * arch_wmb_pmem(), and __arch_has_wmb_pmem().
+ * implementations for arch_memremap_pmem_flags(),
+ * arch_memcpy_to_pmem(), arch_wmb_pmem(), and __arch_has_wmb_pmem().
  */
 
 static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t size)
@@ -54,7 +54,7 @@ static inline void memcpy_from_pmem(void *dst, void __pmem const *src, size_t si
 
 static inline void memunmap_pmem(void __pmem *addr)
 {
-	iounmap((void __force __iomem *) addr);
+	memunmap((void __force *) addr);
 }
 
 /**
@@ -85,16 +85,15 @@ static inline bool arch_has_pmem_api(void)
  * default_memremap_pmem + default_memcpy_to_pmem is sufficient for
  * making data durable relative to i/o completion.
  */
-static void default_memcpy_to_pmem(void __pmem *dst, const void *src,
+static inline void default_memcpy_to_pmem(void __pmem *dst, const void *src,
 		size_t size)
 {
 	memcpy((void __force *) dst, src, size);
 }
 
-static void __pmem *default_memremap_pmem(resource_size_t offset,
-		unsigned long size)
+static inline unsigned long default_memremap_pmem_flags(void)
 {
-	return (void __pmem *) memremap(offset, size, MEMREMAP_WT);
+	return MEMREMAP_WT;
 }
 
 /**
@@ -112,9 +111,14 @@ static void __pmem *default_memremap_pmem(resource_size_t offset,
 static inline void __pmem *memremap_pmem(resource_size_t offset,
 		unsigned long size)
 {
+	unsigned long flags;
+
 	if (arch_has_pmem_api())
-		return arch_memremap_pmem(offset, size);
-	return default_memremap_pmem(offset, size);
+		flags = arch_memremap_pmem_flags(offset, size);
+	else
+		flags = default_memremap_pmem_flags();
+
+	return (void __pmem *) memremap(offset, size, flags);
 }
 
 /**

[PATCH v4 09/10] devres: add devm_memremap

[Dan Williams]

From: Christoph Hellwig <hch@lst.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 include/linux/io.h |    4 ++++
 kernel/memremap.c  |   40 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/include/linux/io.h b/include/linux/io.h
index 3fcf6256c088..d8d749abd665 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -80,6 +80,10 @@ int check_signature(const volatile void __iomem *io_addr,
 			const unsigned char *signature, int length);
 void devm_ioremap_release(struct device *dev, void *res);
 
+void *devm_memremap(struct device *dev, resource_size_t offset,
+		size_t size, unsigned long flags);
+void devm_memunmap(struct device *dev, void *addr);
+
 /*
  * Some systems do not have legacy ISA devices.
  * /dev/port is not a valid interface on these systems.
diff --git a/kernel/memremap.c b/kernel/memremap.c
index a293de52e837..1dbe88088aa1 100644
--- a/kernel/memremap.c
+++ b/kernel/memremap.c
@@ -10,6 +10,7 @@
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License for more details.
  */
+#include <linux/device.h>
 #include <linux/types.h>
 #include <linux/io.h>
 #include <linux/mm.h>
@@ -96,3 +97,42 @@ void memunmap(void *addr)
 		iounmap((void __iomem *) addr);
 }
 EXPORT_SYMBOL(memunmap);
+
+static void devm_memremap_release(struct device *dev, void *res)
+{
+	memunmap(res);
+}
+
+static int devm_memremap_match(struct device *dev, void *res, void *match_data)
+{
+	return *(void **)res == match_data;
+}
+
+void *devm_memremap(struct device *dev, resource_size_t offset,
+		size_t size, unsigned long flags)
+{
+	void **ptr, *addr;
+
+	ptr = devres_alloc(devm_memremap_release, sizeof(*ptr), GFP_KERNEL);
+	if (!ptr)
+		return NULL;
+
+	addr = memremap(offset, size, flags);
+	if (addr) {
+		*ptr = addr;
+		devres_add(dev, ptr);
+	} else
+		devres_free(ptr);
+
+	return addr;
+}
+EXPORT_SYMBOL(devm_memremap);
+
+void devm_memunmap(struct device *dev, void *addr)
+{
+	WARN_ON(devres_destroy(dev, devm_memremap_release, devm_memremap_match,
+			       addr));
+	memunmap(addr);
+}
+EXPORT_SYMBOL(devm_memunmap);
+

[PATCH v4 10/10] pmem: switch to devm_ allocations

[Dan Williams]

From: Christoph Hellwig <hch@lst.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
[djbw: tools/testing/nvdimm/ support]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/nvdimm/pmem.c             |   36 +++++++++--------------------
 include/linux/pmem.h              |    6 ++---
 tools/testing/nvdimm/Kbuild       |    4 ++-
 tools/testing/nvdimm/test/iomap.c |   46 +++++++++++++++++++++----------------
 4 files changed, 42 insertions(+), 50 deletions(-)

diff --git a/drivers/nvdimm/pmem.c b/drivers/nvdimm/pmem.c
index bcf48f133443..eb7552d939e1 100644
--- a/drivers/nvdimm/pmem.c
+++ b/drivers/nvdimm/pmem.c
@@ -119,7 +119,7 @@ static struct pmem_device *pmem_alloc(struct device *dev,
 {
 	struct pmem_device *pmem;
 
-	pmem = kzalloc(sizeof(*pmem), GFP_KERNEL);
+	pmem = devm_kzalloc(dev, sizeof(*pmem), GFP_KERNEL);
 	if (!pmem)
 		return ERR_PTR(-ENOMEM);
 
@@ -128,19 +128,16 @@ static struct pmem_device *pmem_alloc(struct device *dev,
 	if (!arch_has_pmem_api())
 		dev_warn(dev, "unable to guarantee persistence of writes\n");
 
-	if (!request_mem_region(pmem->phys_addr, pmem->size, dev_name(dev))) {
+	if (!devm_request_mem_region(dev, pmem->phys_addr, pmem->size,
+			dev_name(dev))) {
 		dev_warn(dev, "could not reserve region [0x%pa:0x%zx]\n",
 				&pmem->phys_addr, pmem->size);
-		kfree(pmem);
 		return ERR_PTR(-EBUSY);
 	}
 
-	pmem->virt_addr = memremap_pmem(pmem->phys_addr, pmem->size);
-	if (!pmem->virt_addr) {
-		release_mem_region(pmem->phys_addr, pmem->size);
-		kfree(pmem);
+	pmem->virt_addr = memremap_pmem(dev, pmem->phys_addr, pmem->size);
+	if (!pmem->virt_addr)
 		return ERR_PTR(-ENXIO);
-	}
 
 	return pmem;
 }
@@ -210,20 +207,12 @@ static int pmem_rw_bytes(struct nd_namespace_common *ndns,
 	return 0;
 }
 
-static void pmem_free(struct pmem_device *pmem)
-{
-	memunmap_pmem(pmem->virt_addr);
-	release_mem_region(pmem->phys_addr, pmem->size);
-	kfree(pmem);
-}
-
 static int nd_pmem_probe(struct device *dev)
 {
 	struct nd_region *nd_region = to_nd_region(dev->parent);
 	struct nd_namespace_common *ndns;
 	struct nd_namespace_io *nsio;
 	struct pmem_device *pmem;
-	int rc;
 
 	ndns = nvdimm_namespace_common_probe(dev);
 	if (IS_ERR(ndns))
@@ -236,16 +225,14 @@ static int nd_pmem_probe(struct device *dev)
 
 	dev_set_drvdata(dev, pmem);
 	ndns->rw_bytes = pmem_rw_bytes;
+
 	if (is_nd_btt(dev))
-		rc = nvdimm_namespace_attach_btt(ndns);
-	else if (nd_btt_probe(ndns, pmem) == 0) {
+		return nvdimm_namespace_attach_btt(ndns);
+
+	if (nd_btt_probe(ndns, pmem) == 0)
 		/* we'll come back as btt-pmem */
-		rc = -ENXIO;
-	} else
-		rc = pmem_attach_disk(ndns, pmem);
-	if (rc)
-		pmem_free(pmem);
-	return rc;
+		return -ENXIO;
+	return pmem_attach_disk(ndns, pmem);
 }
 
 static int nd_pmem_remove(struct device *dev)
@@ -256,7 +243,6 @@ static int nd_pmem_remove(struct device *dev)
 		nvdimm_namespace_detach_btt(to_nd_btt(dev)->ndns);
 	else
 		pmem_detach_disk(pmem);
-	pmem_free(pmem);
 
 	return 0;
 }
diff --git a/include/linux/pmem.h b/include/linux/pmem.h
index 03f9d73f3e13..eff2e6ba2a1a 100644
--- a/include/linux/pmem.h
+++ b/include/linux/pmem.h
@@ -108,8 +108,8 @@ static inline unsigned long default_memremap_pmem_flags(void)
  * wmb_pmem() arrange for the data to be written through the
  * cache to persistent media.
  */
-static inline void __pmem *memremap_pmem(resource_size_t offset,
-		unsigned long size)
+static inline void __pmem *memremap_pmem(struct device *dev,
+		resource_size_t offset, unsigned long size)
 {
 	unsigned long flags;
 
@@ -118,7 +118,7 @@ static inline void __pmem *memremap_pmem(resource_size_t offset,
 	else
 		flags = default_memremap_pmem_flags();
 
-	return (void __pmem *) memremap(offset, size, flags);
+	return (void __pmem *) devm_memremap(dev, offset, size, flags);
 }
 
 /**
diff --git a/tools/testing/nvdimm/Kbuild b/tools/testing/nvdimm/Kbuild
index 8032a49f7873..04c5fc09576d 100644
--- a/tools/testing/nvdimm/Kbuild
+++ b/tools/testing/nvdimm/Kbuild
@@ -1,9 +1,9 @@
 ldflags-y += --wrap=ioremap_wc
 ldflags-y += --wrap=devm_ioremap_nocache
-ldflags-y += --wrap=memremap
-ldflags-y += --wrap=memunmap
+ldflags-y += --wrap=devm_memremap
 ldflags-y += --wrap=ioremap_nocache
 ldflags-y += --wrap=iounmap
+ldflags-y += --wrap=__devm_request_region
 ldflags-y += --wrap=__request_region
 ldflags-y += --wrap=__release_region
 
diff --git a/tools/testing/nvdimm/test/iomap.c b/tools/testing/nvdimm/test/iomap.c
index 21288f34a5ca..402110cab9e9 100644
--- a/tools/testing/nvdimm/test/iomap.c
+++ b/tools/testing/nvdimm/test/iomap.c
@@ -80,8 +80,8 @@ void __iomem *__wrap_devm_ioremap_nocache(struct device *dev,
 }
 EXPORT_SYMBOL(__wrap_devm_ioremap_nocache);
 
-void *__wrap_memremap(resource_size_t offset, size_t size,
-		unsigned long flags)
+void *__wrap_devm_memremap(struct device *dev, resource_size_t offset,
+		size_t size, unsigned long flags)
 {
 	struct nfit_test_resource *nfit_res;
 
@@ -91,9 +91,9 @@ void *__wrap_memremap(resource_size_t offset, size_t size,
 	if (nfit_res)
 		return (void __iomem *) nfit_res->buf + offset
 			- nfit_res->res->start;
-	return memremap(offset, size, flags);
+	return devm_memremap(dev, offset, size, flags);
 }
-EXPORT_SYMBOL(__wrap_memremap);
+EXPORT_SYMBOL(__wrap_devm_memremap);
 
 void __iomem *__wrap_ioremap_nocache(resource_size_t offset, unsigned long size)
 {
@@ -120,22 +120,9 @@ void __wrap_iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(__wrap_iounmap);
 
-void __wrap_memunmap(void *addr)
-{
-	struct nfit_test_resource *nfit_res;
-
-	rcu_read_lock();
-	nfit_res = get_nfit_res((unsigned long) addr);
-	rcu_read_unlock();
-	if (nfit_res)
-		return;
-	return memunmap(addr);
-}
-EXPORT_SYMBOL(__wrap_memunmap);
-
-struct resource *__wrap___request_region(struct resource *parent,
-		resource_size_t start, resource_size_t n, const char *name,
-		int flags)
+static struct resource *nfit_test_request_region(struct device *dev,
+		struct resource *parent, resource_size_t start,
+		resource_size_t n, const char *name, int flags)
 {
 	struct nfit_test_resource *nfit_res;
 
@@ -163,10 +150,29 @@ struct resource *__wrap___request_region(struct resource *parent,
 			return res;
 		}
 	}
+	if (dev)
+		__devm_request_region(dev, parent, start, n, name);
 	return __request_region(parent, start, n, name, flags);
 }
+
+struct resource *__wrap___request_region(struct resource *parent,
+		resource_size_t start, resource_size_t n, const char *name,
+		int flags)
+{
+	return nfit_test_request_region(NULL, parent, start, n, name, flags);
+}
 EXPORT_SYMBOL(__wrap___request_region);
 
+struct resource *__wrap___devm_request_region(struct device *dev,
+		struct resource *parent, resource_size_t start,
+		resource_size_t n, const char *name)
+{
+	if (!dev)
+		return NULL;
+	return nfit_test_request_region(dev, parent, start, n, name, 0);
+}
+EXPORT_SYMBOL(__wrap___devm_request_region);
+
 void __wrap___release_region(struct resource *parent, resource_size_t start,
 				resource_size_t n)
 {

Re: [PATCH v4 04/10] arch: introduce memremap()

[Christoph Hellwig]

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH v4 06/10] libnvdimm, pmem: push call to ioremap_cache out of line

[Christoph Hellwig]

On Mon, Aug 10, 2015 at 11:38:23PM -0400, Dan Williams wrote:
> In preparation for deprecating ioremap_cache() push its usage into arch
> code where it deleted in a later globabl conversion of ioremap_cache()
> to arch_memremap().

I don't really see the point of this patch.  Two patches later
we'll get rid arch_memremap_pmem anyway.

I'd rather fold this and the next two patches into a single one,
and keep the new arch_memremap_pmem_flags as a inline in io.h.

Re: [PATCH v4 07/10] pmem: switch from ioremap_wt to memremap

[Christoph Hellwig]

On Mon, Aug 10, 2015 at 11:38:28PM -0400, Dan Williams wrote:
> In preparation for deprecating ioremap_wt() convert its usage in
> the PMEM API to memremap.

Looks fine, but the description seems a little confusing.  We're doing
this to get proper semanticss, not to deprecate ioremap_wt().

Signed-off-by: Christoph Hellwig <hch@lst.de>

Re: [PATCH v4 08/10] pmem: convert to generic memremap

[Christoph Hellwig]

On Mon, Aug 10, 2015 at 11:38:33PM -0400, Dan Williams wrote:
> Update memremap_pmem() to query the architecture for the mapping type of
> the given persistent memory range  and then pass those flags to generic
> memremap().  arch_memremap_pmem_flags() is provided an address range to
> evaluate in the event an arch has a need for different mapping types by
> address range.  For example the ACPI NFIT carries EFI mapping types in
> its memory range description table.
> 
> Cc: Ross Zwisler <ross.zwisler@linux.intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Looks generally good, but a little nipick related to my comment
from two patches ago:

> +unsigned long arch_memremap_pmem_flags(resource_size_t offset, size_t size)
> +{
> +	/*
> +	 * The expectation is that pmem is always WB capable range on
> +	 * x86, i.e. no need to walk the range.
> +	 */
> +	return MEMREMAP_WB;
> +}
> +EXPORT_SYMBOL(arch_memremap_pmem_flags);

Why not just add a 

/*
 * The expectation is that pmem is always WB capable range on x86, i.e. no
 * need to walk the range.
 */
#define ARCH_MEMREMAP_PMEM	MEMREMAP_WB

in io.h, and then kill all these little pmem wrappers and:

>  static inline void __pmem *memremap_pmem(resource_size_t offset,
>  		unsigned long size)
>  {
> +	unsigned long flags;
> +
>  	if (arch_has_pmem_api())
> -		return arch_memremap_pmem(offset, size);
> -	return default_memremap_pmem(offset, size);
> +		flags = arch_memremap_pmem_flags(offset, size);
> +	else
> +		flags = default_memremap_pmem_flags();
> +
> +	return (void __pmem *) memremap(offset, size, flags);

#ifdef ARCH_MEMREMAP_PMEM
	return (void __pmem *) memremap(offset, size, ARCH_MEMREMAP_PMEM);
#else
	return (void __pmem *) memremap(offset, size, MEMREMAP_WT);
#endif

Re: [PATCH v4 06/10] libnvdimm, pmem: push call to ioremap_cache out of line

[Dan Williams]

On Tue, Aug 11, 2015 at 5:51 AM, Christoph Hellwig <hch@lst.de> wrote:
> On Mon, Aug 10, 2015 at 11:38:23PM -0400, Dan Williams wrote:
>> In preparation for deprecating ioremap_cache() push its usage into arch
>> code where it deleted in a later globabl conversion of ioremap_cache()
>> to arch_memremap().
>
> I don't really see the point of this patch.  Two patches later
> we'll get rid arch_memremap_pmem anyway.
>
> I'd rather fold this and the next two patches into a single one,
> and keep the new arch_memremap_pmem_flags as a inline in io.h.

Yeah, it made more sense at its position in the old series, but now
that ioremap_cache() will be around for one last development cycle we
can squash this.