ARM: implement CONFIG_STRICT_DEVMEM by disabling access to RAM via /dev/mem
There are very few legitimate use cases, if any, for directly accessing
system RAM through /dev/mem. So let's mimic what they do on x86 and
forbid it when CONFIG_STRICT_DEVMEM is turned on.
Signed-off-by: Nicolas Pitre <nicolas.pitre@linaro.org>
diff --git a/arch/arm/include/asm/io.h b/arch/arm/include/asm/io.h
index 1261b1f9..815efa2 100644
--- a/arch/arm/include/asm/io.h
+++ b/arch/arm/include/asm/io.h
@@ -294,6 +294,7 @@
#define ARCH_HAS_VALID_PHYS_ADDR_RANGE
extern int valid_phys_addr_range(unsigned long addr, size_t size);
extern int valid_mmap_phys_addr_range(unsigned long pfn, size_t size);
+extern int devmem_is_allowed(unsigned long pfn);
#endif
/*