diff options
| author | Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> | 2015-12-01 09:06:50 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2015-12-14 15:19:12 +1100 |
| commit | c6a3c495f05a070d4c4016d4a51c384cba723971 (patch) | |
| tree | 6d80845b8ff67e57533312085de88c5fb67c16d2 /arch/powerpc/mm/hash_utils_64.c | |
| parent | a43c0eb8364c022725df586e91dd753633374d66 (diff) | |
| download | linux-c6a3c495f05a070d4c4016d4a51c384cba723971.tar.gz | |
powerpc/mm: Add helper for converting pte bit to hpte bits
Instead of open coding it in multiple code paths, export the helper
and add more documentation. Also make sure we don't make assumption
regarding pte bit position
Acked-by: Scott Wood <scottwood@freescale.com>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/mm/hash_utils_64.c')
| -rw-r--r-- | arch/powerpc/mm/hash_utils_64.c | 22 |
1 files changed, 14 insertions, 8 deletions
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c index cab2deb8d20b2..6c67bd0bec557 100644 --- a/arch/powerpc/mm/hash_utils_64.c +++ b/arch/powerpc/mm/hash_utils_64.c @@ -159,20 +159,26 @@ static struct mmu_psize_def mmu_psize_defaults_gp[] = { }, }; -static unsigned long htab_convert_pte_flags(unsigned long pteflags) +unsigned long htab_convert_pte_flags(unsigned long pteflags) { - unsigned long rflags = pteflags & 0x1fa; + unsigned long rflags = 0; /* _PAGE_EXEC -> NOEXEC */ if ((pteflags & _PAGE_EXEC) == 0) rflags |= HPTE_R_N; - - /* PP bits. PAGE_USER is already PP bit 0x2, so we only - * need to add in 0x1 if it's a read-only user page + /* + * PP bits: + * Linux use slb key 0 for kernel and 1 for user. + * kernel areas are mapped by PP bits 00 + * and and there is no kernel RO (_PAGE_KERNEL_RO). + * User area mapped by 0x2 and read only use by + * 0x3. */ - if ((pteflags & _PAGE_USER) && !((pteflags & _PAGE_RW) && - (pteflags & _PAGE_DIRTY))) - rflags |= 1; + if (pteflags & _PAGE_USER) { + rflags |= 0x2; + if (!((pteflags & _PAGE_RW) && (pteflags & _PAGE_DIRTY))) + rflags |= 0x1; + } /* * Always add "C" bit for perf. Memory coherence is always enabled */ |