Implement huge I/O mapping capability interfaces on x86.
Also define IOREMAP_MAX_ORDER to the size of PUD or PMD on x86.
When IOREMAP_MAX_ORDER is not defined on x86, it will be defined
to the default value in <linux/vmalloc.h>.
Signed-off-by: Toshi Kani <toshi.kani@xxxxxx>
---
arch/x86/include/asm/page_types.h | 8 ++++++++
arch/x86/mm/ioremap.c | 16 ++++++++++++++++
2 files changed, 24 insertions(+)
diff --git a/arch/x86/include/asm/page_types.h b/arch/x86/include/asm/page_types.h
index f97fbe3..debbfff 100644
--- a/arch/x86/include/asm/page_types.h
+++ b/arch/x86/include/asm/page_types.h
@@ -38,6 +38,14 @@
#define __START_KERNEL (__START_KERNEL_map + __PHYSICAL_START)
+#ifdef CONFIG_HUGE_IOMAP
+#ifdef CONFIG_X86_64
+#define IOREMAP_MAX_ORDER (PUD_SHIFT)
+#elif defined(PMD_SHIFT)
+#define IOREMAP_MAX_ORDER (PMD_SHIFT)
+#endif
+#endif /* CONFIG_HUGE_IOMAP */
+
#ifdef CONFIG_X86_64
#include <asm/page_64_types.h>
#else
diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index fdf617c..ef32bec 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -326,6 +326,22 @@ void iounmap(volatile void __iomem *addr)
}
EXPORT_SYMBOL(iounmap);
+#ifdef CONFIG_HUGE_IOMAP
+int arch_ioremap_pud_supported(void)
+{
+#ifdef CONFIG_X86_64
+ return cpu_has_gbpages;
+#else
+ return 0;
+#endif
+}
+
+int arch_ioremap_pmd_supported(void)
+{
+ return cpu_has_pse;
+}
+#endif /* CONFIG_HUGE_IOMAP */
+
/*
* Convert a physical pointer to a virtual kernel pointer for /dev/mem
* access
--
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