add devm_memremap_pages
This behaves like devm_memremap except that it ensures we have page
structures available that can back the region.
Signed-off-by: Christoph Hellwig <hch@lst.de>
[djbw: catch attempts to remap RAM, drop flags]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
diff --git a/include/linux/io.h b/include/linux/io.h
index d8d749a..de64c1e 100644
--- a/include/linux/io.h
+++ b/include/linux/io.h
@@ -20,10 +20,13 @@
#include <linux/types.h>
#include <linux/init.h>
+#include <linux/bug.h>
+#include <linux/err.h>
#include <asm/io.h>
#include <asm/page.h>
struct device;
+struct resource;
__visible void __iowrite32_copy(void __iomem *to, const void *from, size_t count);
void __iowrite64_copy(void __iomem *to, const void *from, size_t count);
@@ -84,6 +87,23 @@
size_t size, unsigned long flags);
void devm_memunmap(struct device *dev, void *addr);
+void *__devm_memremap_pages(struct device *dev, struct resource *res);
+
+#ifdef CONFIG_ZONE_DEVICE
+void *devm_memremap_pages(struct device *dev, struct resource *res);
+#else
+static inline void *devm_memremap_pages(struct device *dev, struct resource *res)
+{
+ /*
+ * Fail attempts to call devm_memremap_pages() without
+ * ZONE_DEVICE support enabled, this requires callers to fall
+ * back to plain devm_memremap() based on config
+ */
+ WARN_ON_ONCE(1);
+ return ERR_PTR(-ENXIO);
+}
+#endif
+
/*
* Some systems do not have legacy ISA devices.
* /dev/port is not a valid interface on these systems.