Merge branch 'linus' into x86/asm, before applying dependent patch

Signed-off-by: Ingo Molnar <mingo@kernel.org>

1 files changed, 29 insertions, 8 deletions

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index fdf617c00e2f..70e7444c6835 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -67,8 +67,13 @@ static int __ioremap_check_ram(unsigned long start_pfn, unsigned long nr_pages,
 
 /*
  * Remap an arbitrary physical address space into the kernel virtual
- * address space. Needed when the kernel wants to access high addresses
- * directly.
+ * address space. It transparently creates kernel huge I/O mapping when
+ * the physical address is aligned by a huge page size (1GB or 2MB) and
+ * the requested size is at least the huge page size.
+ *
+ * NOTE: MTRRs can override PAT memory types with a 4KB granularity.
+ * Therefore, the mapping code falls back to use a smaller page toward 4KB
+ * when a mapping range is covered by non-WB type of MTRRs.
  *
  * NOTE! We need to allow non-page-aligned mappings too: we will obviously
  * have to convert them into an offset in a page-aligned mapping, but the
@@ -326,24 +331,40 @@ void iounmap(volatile void __iomem *addr)
 }
 EXPORT_SYMBOL(iounmap);
 
+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;
+}
+
 /*
  * Convert a physical pointer to a virtual kernel pointer for /dev/mem
  * access
  */
 void *xlate_dev_mem_ptr(phys_addr_t phys)
 {
-	void *addr;
-	unsigned long start = phys & PAGE_MASK;
+	unsigned long start  = phys &  PAGE_MASK;
+	unsigned long offset = phys & ~PAGE_MASK;
+	unsigned long vaddr;
 
 	/* If page is RAM, we can use __va. Otherwise ioremap and unmap. */
 	if (page_is_ram(start >> PAGE_SHIFT))
 		return __va(phys);
 
-	addr = (void __force *)ioremap_cache(start, PAGE_SIZE);
-	if (addr)
-		addr = (void *)((unsigned long)addr | (phys & ~PAGE_MASK));
+	vaddr = (unsigned long)ioremap_cache(start, PAGE_SIZE);
+	/* Only add the offset on success and return NULL if the ioremap() failed: */
+	if (vaddr)
+		vaddr += offset;
 
-	return addr;
+	return (void *)vaddr;
 }
 
 void unxlate_dev_mem_ptr(phys_addr_t phys, void *addr)