module: merge module_alloc() finally

As Christoph Hellwig suggested, module_alloc() actually can be
unified for i386 and x86_64 (of course, also UML).

Signed-off-by: WANG Cong <amwang@redhat.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: 'Ingo Molnar' <mingo@elte.hu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

arch/um/include/asm/pgtable.h

@@ -53,16 +53,21 @@ extern unsigned long end_iomem;
 #else
 # define VMALLOC_END	(FIXADDR_START-2*PAGE_SIZE)
 #endif
+#define MODULES_VADDR	VMALLOC_START
+#define MODULES_END	VMALLOC_END
+#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
 
 #define _PAGE_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED | _PAGE_DIRTY)
 #define _KERNPG_TABLE	(_PAGE_PRESENT | _PAGE_RW | _PAGE_ACCESSED | _PAGE_DIRTY)
 #define _PAGE_CHG_MASK	(PAGE_MASK | _PAGE_ACCESSED | _PAGE_DIRTY)
-
+#define __PAGE_KERNEL_EXEC                                              \
+	 (_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
 #define PAGE_NONE	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
 #define PAGE_SHARED	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | _PAGE_ACCESSED)
 #define PAGE_COPY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
 #define PAGE_READONLY	__pgprot(_PAGE_PRESENT | _PAGE_USER | _PAGE_ACCESSED)
 #define PAGE_KERNEL	__pgprot(_PAGE_PRESENT | _PAGE_RW | _PAGE_DIRTY | _PAGE_ACCESSED)
+#define PAGE_KERNEL_EXEC	__pgprot(__PAGE_KERNEL_EXEC)
 
 /*
  * The i386 can't do page protection for execute, and considers that the same

arch/x86/include/asm/pgtable_32_types.h

@@ -46,6 +46,10 @@ extern bool __vmalloc_start_set; /* set once high_memory is set */
 # define VMALLOC_END	(FIXADDR_START - 2 * PAGE_SIZE)
 #endif
 
+#define MODULES_VADDR	VMALLOC_START
+#define MODULES_END	VMALLOC_END
+#define MODULES_LEN	(MODULES_VADDR - MODULES_END)
+
 #define MAXMEM	(VMALLOC_END - PAGE_OFFSET - __VMALLOC_RESERVE)
 
 #endif /* _ASM_X86_PGTABLE_32_DEFS_H */

arch/x86/kernel/module.c

@@ -34,14 +34,6 @@
 #define DEBUGP(fmt...)
 #endif
 
-#if defined(CONFIG_UML) || defined(CONFIG_X86_32)
-void *module_alloc(unsigned long size)
-{
-	if (size == 0)
-		return NULL;
-	return vmalloc_exec(size);
-}
-#else /*X86_64*/
 void *module_alloc(unsigned long size)
 {
 	struct vm_struct *area;
@@ -56,9 +48,9 @@ void *module_alloc(unsigned long size)
 	if (!area)
 		return NULL;
 
-	return __vmalloc_area(area, GFP_KERNEL, PAGE_KERNEL_EXEC);
+	return __vmalloc_area(area, GFP_KERNEL | __GFP_HIGHMEM,
+					PAGE_KERNEL_EXEC);
 }
-#endif
 
 /* Free memory returned from module_alloc */
 void module_free(struct module *mod, void *module_region)