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| author | Christophe Leroy <christophe.leroy@c-s.fr> | 2020-03-10 18:29:12 +0100 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-03-25 02:09:27 +0100 |
| commit | 697ece78f8f749aeea40f2711389901f0974017a (patch) | |
| tree | 9fa49406f4fab3d95af9d8376f9c0fe63753fc0a /arch/powerpc/kernel | |
| parent | powerpc/kasan: Fix kasan_remap_early_shadow_ro() (diff) | |
| download | linux-697ece78f8f749aeea40f2711389901f0974017a.tar.xz linux-697ece78f8f749aeea40f2711389901f0974017a.zip | |
powerpc/32s: reorder Linux PTE bits to better match Hash PTE bits.
Reorder Linux PTE bits to (almost) match Hash PTE bits.
RW Kernel : PP = 00
RO Kernel : PP = 00
RW User : PP = 01
RO User : PP = 11
So naturally, we should have
_PAGE_USER = 0x001
_PAGE_RW = 0x002
Today 0x001 and 0x002 and _PAGE_PRESENT and _PAGE_HASHPTE which
both are software only bits.
Switch _PAGE_USER and _PAGE_PRESET
Switch _PAGE_RW and _PAGE_HASHPTE
This allows to remove a few insns.
Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/c4d6c18a7f8d9d3b899bc492f55fbc40ef38896a.1583861325.git.christophe.leroy@c-s.fr
Diffstat (limited to 'arch/powerpc/kernel')
| -rw-r--r-- | arch/powerpc/kernel/head_32.S | 9 |
1 files changed, 3 insertions, 6 deletions
diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index 97c887950c3c..daaa153950c2 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -348,7 +348,7 @@ BEGIN_MMU_FTR_SECTION andis. r0, r5, (DSISR_BAD_FAULT_32S | DSISR_DABRMATCH)@h #endif bne handle_page_fault_tramp_2 /* if not, try to put a PTE */ - rlwinm r3, r5, 32 - 15, 21, 21 /* DSISR_STORE -> _PAGE_RW */ + rlwinm r3, r5, 32 - 24, 30, 30 /* DSISR_STORE -> _PAGE_RW */ bl hash_page b handle_page_fault_tramp_1 FTR_SECTION_ELSE @@ -497,7 +497,6 @@ InstructionTLBMiss: andc. r1,r1,r0 /* check access & ~permission */ bne- InstructionAddressInvalid /* return if access not permitted */ /* Convert linux-style PTE to low word of PPC-style PTE */ - rlwimi r0,r0,32-2,31,31 /* _PAGE_USER -> PP lsb */ ori r1, r1, 0xe06 /* clear out reserved bits */ andc r1, r0, r1 /* PP = user? 1 : 0 */ BEGIN_FTR_SECTION @@ -565,9 +564,8 @@ DataLoadTLBMiss: * we would need to update the pte atomically with lwarx/stwcx. */ /* Convert linux-style PTE to low word of PPC-style PTE */ - rlwinm r1,r0,32-9,30,30 /* _PAGE_RW -> PP msb */ - rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ - rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */ + rlwinm r1,r0,0,30,30 /* _PAGE_RW -> PP msb */ + rlwimi r0,r0,1,30,30 /* _PAGE_USER -> PP msb */ ori r1,r1,0xe04 /* clear out reserved bits */ andc r1,r0,r1 /* PP = user? rw? 1: 3: 0 */ BEGIN_FTR_SECTION @@ -645,7 +643,6 @@ DataStoreTLBMiss: * we would need to update the pte atomically with lwarx/stwcx. */ /* Convert linux-style PTE to low word of PPC-style PTE */ - rlwimi r0,r0,32-2,31,31 /* _PAGE_USER -> PP lsb */ li r1,0xe06 /* clear out reserved bits & PP msb */ andc r1,r0,r1 /* PP = user? 1: 0 */ BEGIN_FTR_SECTION |