Messages in this thread | | | Date | Mon, 6 Aug 2012 09:30:00 -0400 | From | Cyril Chemparathy <> | Subject | Re: [PATCH 03/22] ARM: LPAE: use phys_addr_t on virt <--> phys conversion |
| |
On 8/6/2012 7:14 AM, Russell King - ARM Linux wrote: > On Tue, Jul 31, 2012 at 07:04:39PM -0400, Cyril Chemparathy wrote: >> This patch fixes up the types used when converting back and forth between >> physical and virtual addresses. >> >> Signed-off-by: Vitaly Andrianov <vitalya@ti.com> >> Signed-off-by: Cyril Chemparathy <cyril@ti.com> >> --- >> arch/arm/include/asm/memory.h | 17 +++++++++++------ >> 1 file changed, 11 insertions(+), 6 deletions(-) >> >> diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h >> index 01c710d..4a0108f 100644 >> --- a/arch/arm/include/asm/memory.h >> +++ b/arch/arm/include/asm/memory.h >> @@ -157,22 +157,27 @@ extern unsigned long __pv_phys_offset; >> >> extern unsigned long __pv_offset; >> >> -static inline unsigned long __virt_to_phys(unsigned long x) >> +static inline phys_addr_t __virt_to_phys(unsigned long x) >> { >> unsigned long t; >> early_patch_imm8(x, t, "add", __pv_offset); >> return t; >> } >> >> -static inline unsigned long __phys_to_virt(unsigned long x) >> +static inline unsigned long __phys_to_virt(phys_addr_t x) >> { >> unsigned long t; >> early_patch_imm8(x, t, "sub", __pv_offset); >> return t; >> } >> #else >> -#define __virt_to_phys(x) ((x) - PAGE_OFFSET + PHYS_OFFSET) >> -#define __phys_to_virt(x) ((x) - PHYS_OFFSET + PAGE_OFFSET) >> + >> +#define __virt_to_phys(x) \ >> + ((phys_addr_t)(x) - PAGE_OFFSET + PHYS_OFFSET) >> + >> +#define __phys_to_virt(x) \ >> + ((unsigned long)((phys_addr_t)(x) - PHYS_OFFSET + PAGE_OFFSET)) >> + >> #endif >> #endif >> >> @@ -207,14 +212,14 @@ static inline phys_addr_t virt_to_phys(const volatile void *x) >> >> static inline void *phys_to_virt(phys_addr_t x) >> { >> - return (void *)(__phys_to_virt((unsigned long)(x))); >> + return (void *)__phys_to_virt(x); >> } >> >> /* >> * Drivers should NOT use these either. >> */ >> #define __pa(x) __virt_to_phys((unsigned long)(x)) >> -#define __va(x) ((void *)__phys_to_virt((unsigned long)(x))) >> +#define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) >> #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) > > This as a whole does not fill me with a great amount of enthusiasm, > because it breaks some of the typechecking that we have here. > > The whole point of __phys_to_virt() and __virt_to_phys() is that they work > on integer types, and warn if you dare to use them with pointers. Adding > a cast into them breaks that. >
Understood. Thanks. The casts were needed to upgrade to 64-bit before arithmetic. We should convert the non-patch __phys_to_virt and __virt_to_phys to inlines to keep the typechecking intact.
> The whole point is that the typecasting is explicitly inside phys_to_virt() > and virt_to_phys() and not their macro counterparts. > > Secondly, are you sure that this patch is correct on its own? You're > passing a u64 into assembly only expecting a 32-bit register. Have you > checked it does the right thing with a 64-bit phys_addr_t on both LE > and BE? >
We should explicitly pass in the lower order bits here, at least until the next patch in the series fixes things up for 64-bit. Thanks.
We've tested with 64-bit and 32-bit phys_addr_t, but only on LE. Thanks for pointing this out, we'll figure out a way to run BE as well.
-- Thanks - Cyril
| |