X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=arch%2Farm%2Fmm%2Fmmap.c;h=b0a98305055c53e54cc9be3edda6c82afb6275b8;hb=04cc69768e7d1f40d98b79d23d203674553b4da2;hp=4f5b39687df541a417d4c3a9ac888fc53a31b999;hpb=14a4fa20a10d76eb98b7feb25be60735217929ba;p=pandora-kernel.git

diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c
index 4f5b39687df5..b0a98305055c 100644
--- a/arch/arm/mm/mmap.c
+++ b/arch/arm/mm/mmap.c
@@ -144,3 +144,25 @@ int valid_mmap_phys_addr_range(unsigned long pfn, size_t size)
 {
 	return !(pfn + (size >> PAGE_SHIFT) > 0x00100000);
 }
+
+#ifdef CONFIG_STRICT_DEVMEM
+
+#include <linux/ioport.h>
+
+/*
+ * devmem_is_allowed() checks to see if /dev/mem access to a certain
+ * address is valid. The argument is a physical page number.
+ * We mimic x86 here by disallowing access to system RAM as well as
+ * device-exclusive MMIO regions. This effectively disable read()/write()
+ * on /dev/mem.
+ */
+int devmem_is_allowed(unsigned long pfn)
+{
+	if (iomem_is_exclusive(pfn << PAGE_SHIFT))
+		return 0;
+	if (!page_is_ram(pfn))
+		return 1;
+	return 0;
+}
+
+#endif