ARM: LPAE: use signed arithmetic for mask definitions
authorCyril Chemparathy <cyril@ti.com>
Sun, 22 Jul 2012 17:40:38 +0000 (13:40 -0400)
committerWill Deacon <will.deacon@arm.com>
Thu, 30 May 2013 15:01:30 +0000 (16:01 +0100)
This patch applies to PAGE_MASK, PMD_MASK, and PGDIR_MASK, where forcing
unsigned long math truncates the mask at the 32-bits.  This clearly does bad
things on PAE systems.

This patch fixes this problem by defining these masks as signed quantities.
We then rely on sign extension to do the right thing.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Signed-off-by: Vitaly Andrianov <vitalya@ti.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Tested-by: Subash Patel <subash.rp@samsung.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm/include/asm/page.h
arch/arm/include/asm/pgtable-3level.h

index 812a494..6363f3d 100644 (file)
@@ -13,7 +13,7 @@
 /* PAGE_SHIFT determines the page size */
 #define PAGE_SHIFT             12
 #define PAGE_SIZE              (_AC(1,UL) << PAGE_SHIFT)
-#define PAGE_MASK              (~(PAGE_SIZE-1))
+#define PAGE_MASK              (~((1 << PAGE_SHIFT) - 1))
 
 #ifndef __ASSEMBLY__
 
index 86b8fe3..5b85b21 100644 (file)
 #define PMD_SHIFT              21
 
 #define PMD_SIZE               (1UL << PMD_SHIFT)
-#define PMD_MASK               (~(PMD_SIZE-1))
+#define PMD_MASK               (~((1 << PMD_SHIFT) - 1))
 #define PGDIR_SIZE             (1UL << PGDIR_SHIFT)
-#define PGDIR_MASK             (~(PGDIR_SIZE-1))
+#define PGDIR_MASK             (~((1 << PGDIR_SHIFT) - 1))
 
 /*
  * section address mask and size definitions.
  */
 #define SECTION_SHIFT          21
 #define SECTION_SIZE           (1UL << SECTION_SHIFT)
-#define SECTION_MASK           (~(SECTION_SIZE-1))
+#define SECTION_MASK           (~((1 << SECTION_SHIFT) - 1))
 
 #define USER_PTRS_PER_PGD      (PAGE_OFFSET / PGDIR_SIZE)