ARM: cacheflush: don't round address range up to nearest page
authorWill Deacon <will.deacon@arm.com>
Tue, 21 Aug 2012 14:33:19 +0000 (15:33 +0100)
committerWill Deacon <will.deacon@arm.com>
Tue, 20 Aug 2013 10:54:54 +0000 (11:54 +0100)
The flush_cache_user_range macro takes a pair of addresses describing
the start and end of the virtual address range to flush. Due to an
accidental oversight when flush_cache_range_user was introduced, the
address range was rounded up so that the start and end addresses were
page-aligned.

For historical reference, the interesting commits in history.git are:

10eacf1775e1 ("[ARM] Clean up ARM cache handling interfaces (part 1)")
71432e79b76b ("[ARM] Add flush_cache_user_page() for sys_cacheflush()")

This patch removes the alignment code, reducing the amount of flushing
required for ranges that are not an exact multiple of PAGE_SIZE.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reported-by: Jonathan Austin <jonathan.austin@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm/include/asm/cacheflush.h

index 17d0ae8672fa666b8d1e43ae40b0226e1bd04ac8..bfd37e58f855f86b3da18c66ae35e88eed8a0672 100644 (file)
@@ -268,8 +268,7 @@ extern void flush_cache_page(struct vm_area_struct *vma, unsigned long user_addr
  * Harvard caches are synchronised for the user space address range.
  * This is used for the ARM private sys_cacheflush system call.
  */
-#define flush_cache_user_range(start,end) \
-       __cpuc_coherent_user_range((start) & PAGE_MASK, PAGE_ALIGN(end))
+#define flush_cache_user_range(s,e)    __cpuc_coherent_user_range(s,e)
 
 /*
  * Perform necessary cache operations to ensure that data previously