[PATCH] mm: move is_ioremap_addr() into new header file

[Baoquan He]

Now is_ioremap_addr() is only used in kernel/iomem.c and gonna be used
in mm/ioremap.c. Move it into its own new header file linux/ioremap.h.

Signed-off-by: Baoquan He <bhe@xxxxxxxxxx>
---
 include/linux/ioremap.h | 29 +++++++++++++++++++++++++++++
 include/linux/mm.h      |  5 -----
 kernel/iomem.c          |  1 +
 mm/ioremap.c            |  1 +
 4 files changed, 31 insertions(+), 5 deletions(-)
 create mode 100644 include/linux/ioremap.h

diff --git a/include/linux/ioremap.h b/include/linux/ioremap.h
new file mode 100644
index 000000000000..2fd51a77ebdc
--- /dev/null
+++ b/include/linux/ioremap.h
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_IOREMAP_H
+#define _LINUX_IOREMAP_H
+
+#include <linux/kasan.h>
+#include <asm/pgtable.h>
+
+#if defined(CONFIG_HAS_IOMEM) || defined(CONFIG_GENERIC_IOREMAP)
+/*
+ * Ioremap often, but not always uses the generic vmalloc area. E.g on
+ * Power ARCH, it could have different ioremap space. 
+ */
+#ifndef IOREMAP_START
+#define IOREMAP_START   VMALLOC_START
+#define IOREMAP_END     VMALLOC_END
+#endif
+static inline bool is_ioremap_addr(const void *x)
+{
+	unsigned long addr = (unsigned long)kasan_reset_tag(x);
+	return addr >= IOREMAP_START && addr < IOREMAP_END;
+}
+#else
+static inline bool is_ioremap_addr(const void *x)
+{
+	return false;
+}
+#endif
+
+#endif /* _LINUX_IOREMAP_H */
diff --git a/include/linux/mm.h b/include/linux/mm.h
index 27ce77080c79..7379f19768b4 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -1041,11 +1041,6 @@ unsigned long vmalloc_to_pfn(const void *addr);
  * On nommu, vmalloc/vfree wrap through kmalloc/kfree directly, so there
  * is no special casing required.
  */
-
-#ifndef is_ioremap_addr
-#define is_ioremap_addr(x) is_vmalloc_addr(x)
-#endif
-
 #ifdef CONFIG_MMU
 extern bool is_vmalloc_addr(const void *x);
 extern int is_vmalloc_or_module_addr(const void *x);
diff --git a/kernel/iomem.c b/kernel/iomem.c
index 62c92e43aa0d..9682471e6471 100644
--- a/kernel/iomem.c
+++ b/kernel/iomem.c
@@ -3,6 +3,7 @@
 #include <linux/types.h>
 #include <linux/io.h>
 #include <linux/mm.h>
+#include <linux/ioremap.h>
 
 #ifndef ioremap_cache
 /* temporary while we convert existing ioremap_cache users to memremap */
diff --git a/mm/ioremap.c b/mm/ioremap.c
index 0248e630561b..3dede3302eba 100644
--- a/mm/ioremap.c
+++ b/mm/ioremap.c
@@ -10,6 +10,7 @@
 #include <linux/mm.h>
 #include <linux/io.h>
 #include <linux/export.h>
+#include <linux/ioremap.h>
 
 /*
  * Ioremap often, but not always uses the generic vmalloc area. E.g on
-- 
2.34.1

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