From 78ca1108b10927b3d068c8da91352b0f4cd01fc5 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Fri, 25 Jan 2019 12:34:20 +0000 Subject: [PATCH] powerpc/book3s32: Reorder _PAGE_XXX flags to simplify TLB handling For pages without _PAGE_USER, PP field is 00 For pages with _PAGE_USER, PP field is 10 for RW and 11 for RO. This patch sets _PAGE_USER to 0x002 and _PAGE_RW to 0x001 is order to simplify TLB handling by reducing amount of shifts. The location of _PAGE_PRESENT and _PAGE_HASHPTE doesn't matter as they are only SW related flags. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman --- arch/powerpc/include/asm/book3s/32/hash.h | 8 ++++---- arch/powerpc/kernel/head_32.S | 5 +---- arch/powerpc/mm/hash_low_32.S | 6 ++---- 3 files changed, 7 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/32/hash.h b/arch/powerpc/include/asm/book3s/32/hash.h index 2a0a467..a5907ea 100644 --- a/arch/powerpc/include/asm/book3s/32/hash.h +++ b/arch/powerpc/include/asm/book3s/32/hash.h @@ -17,9 +17,9 @@ * updating the accessed and modified bits in the page table tree. */ -#define _PAGE_PRESENT 0x001 /* software: pte contains a translation */ -#define _PAGE_HASHPTE 0x002 /* hash_page has made an HPTE for this pte */ -#define _PAGE_USER 0x004 /* usermode access allowed */ +#define _PAGE_RW 0x001 /* PP = x1: user write access allowed */ +#define _PAGE_USER 0x002 /* PP = 1x: usermode access allowed */ +#define _PAGE_HASHPTE 0x004 /* software: hash_page has made an HPTE for this pte */ #define _PAGE_GUARDED 0x008 /* G: prohibit speculative access */ #define _PAGE_COHERENT 0x010 /* M: enforce memory coherence (SMP systems) */ #define _PAGE_NO_CACHE 0x020 /* I: cache inhibit */ @@ -27,7 +27,7 @@ #define _PAGE_DIRTY 0x080 /* C: page changed */ #define _PAGE_ACCESSED 0x100 /* R: page referenced */ #define _PAGE_EXEC 0x200 /* software: exec allowed */ -#define _PAGE_RW 0x400 /* software: user write access allowed */ +#define _PAGE_PRESENT 0x400 /* software: pte contains a translation */ #define _PAGE_SPECIAL 0x800 /* software: Special page */ #ifdef CONFIG_PTE_64BIT diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index fdb587c..e7a5b31 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -522,7 +522,6 @@ 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,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ ori r1, r1, 0xe05 /* clear out reserved bits */ andc r1, r0, r1 /* PP = user? 2 : 0 */ BEGIN_FTR_SECTION @@ -590,8 +589,7 @@ 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,r0,32-10,31,31 /* _PAGE_RW -> PP lsb */ - rlwimi r0,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ + rlwinm r1, r0, 0, 31, 31 /* _PAGE_RW -> PP lsb */ rlwimi r0,r0,32-1,31,31 /* _PAGE_USER -> PP lsb */ ori r1,r1,0xe04 /* clear out reserved bits */ andc r1,r0,r1 /* PP = user? rw? 2: 3: 0 */ @@ -670,7 +668,6 @@ 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,r0,32-1,30,30 /* _PAGE_USER -> PP msb */ li r1,0xe05 /* clear out reserved bits & PP lsb */ andc r1,r0,r1 /* PP = user? 2: 0 */ BEGIN_FTR_SECTION diff --git a/arch/powerpc/mm/hash_low_32.S b/arch/powerpc/mm/hash_low_32.S index d94fef5..f4294ed 100644 --- a/arch/powerpc/mm/hash_low_32.S +++ b/arch/powerpc/mm/hash_low_32.S @@ -310,11 +310,9 @@ Hash_msk = (((1 << Hash_bits) - 1) * 64) _GLOBAL(create_hpte) /* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */ - rlwinm r8,r5,32-10,31,31 /* _PAGE_RW -> PP lsb */ rlwinm r0,r5,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */ - and r8,r8,r0 /* writable if _RW & _DIRTY */ - rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */ - rlwimi r5,r5,32-2,31,31 /* _PAGE_USER -> PP lsb */ + and r8, r5, r0 /* writable if _RW & _DIRTY */ + rlwimi r5, r5, 32 - 1, 31, 31 /* _PAGE_USER -> PP lsb */ ori r8,r8,0xe04 /* clear out reserved bits */ andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */ BEGIN_FTR_SECTION -- 2.7.4