x86_64/mm: check and print vmemmap allocation continuous

[linux-2.6] / arch / x86 / mm / ioremap.c

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 36a3f7ded6262c7063ee291e1aa55082a917771f..d176b23110cc875187be67d3c22f227ec38cbdeb 100644 (file)
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -336,6 +336,35 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
+/*
+ * Convert a physical pointer to a virtual kernel pointer for /dev/mem
+ * access
+ */
+void *xlate_dev_mem_ptr(unsigned long phys)
+{
+       void *addr;
+       unsigned long start = phys & PAGE_MASK;
+
+       /* If page is RAM, we can use __va. Otherwise ioremap and unmap. */
+       if (page_is_ram(start >> PAGE_SHIFT))
+               return __va(phys);
+
+       addr = (void *)ioremap(start, PAGE_SIZE);
+       if (addr)
+               addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));
+
+       return addr;
+}
+
+void unxlate_dev_mem_ptr(unsigned long phys, void *addr)
+{
+       if (page_is_ram(phys >> PAGE_SHIFT))
+               return;
+
+       iounmap((void __iomem *)((unsigned long)addr & PAGE_MASK));
+       return;
+}
+
 #ifdef CONFIG_X86_32
 
 int __initdata early_ioremap_debug;