linux/arch
Ard Biesheuvel 8439e62a15 arm64: mm: use bit ops rather than arithmetic in pa/va translations
Since PAGE_OFFSET is chosen such that it cuts the kernel VA space right
in half, and since the size of the kernel VA space itself is always a
power of 2, we can treat PAGE_OFFSET as a bitmask and replace the
additions/subtractions with 'or' and 'and-not' operations.

For the comparison against PAGE_OFFSET, a mov/cmp/branch sequence ends
up getting replaced with a single tbz instruction. For the additions and
subtractions, we save a mov instruction since the mask is folded into the
instruction's immediate field.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-23 17:43:25 +00:00
..
alpha dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
arc ARC fixes for 4.5 2016-02-13 08:18:21 -08:00
arm arm64: kvm: deal with kernel symbols outside of linear mapping 2016-02-18 18:16:40 +00:00
arm64 arm64: mm: use bit ops rather than arithmetic in pa/va translations 2016-02-23 17:43:25 +00:00
avr32 dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
blackfin dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
c6x dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
cris Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
frv dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
h8300 Merge branch 'akpm' (patches from Andrew) 2016-01-21 12:32:08 -08:00
hexagon dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
ia64 [IA64] Enable copy_file_range syscall for ia64 2016-01-22 14:20:01 -08:00
m32r m32r: fix build failure due to SMP and MMU 2016-02-05 18:10:40 -08:00
m68k dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
metag dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
microblaze dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
mips Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2016-02-14 10:49:01 -08:00
mn10300 dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
nios2 dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
openrisc dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
parisc dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
powerpc powerpc fixes for 4.5 2016-01-29 16:10:16 -08:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2016-01-29 16:05:18 -08:00
score
sh sh: fix smp_store_mb for !SMP 2016-01-26 10:18:29 +02:00
sparc dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
tile dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
um um: asm/page.h: remove the pte_high member from struct pte_t 2016-02-05 18:10:40 -08:00
unicore32 dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00
x86 Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-02-14 10:50:26 -08:00
xtensa dma-mapping: remove <asm-generic/dma-coherent.h> 2016-01-20 17:09:18 -08:00
.gitignore
Kconfig dma-mapping: always provide the dma_map_ops based implementation 2016-01-20 17:09:18 -08:00