Re: [PATCH v2 7/8] powerpc/pgtable: remove _PAGE_BIT_SWAP_TYPE for book3s
From: Christophe Leroy <hidden>
Date: 2022-03-30 06:07:30
Also in:
linux-arm-kernel, linux-mm, linux-s390, lkml
Le 29/03/2022 à 18:43, David Hildenbrand a écrit :
The swap type is simply stored in bits 0x1f of the swap pte. Let's simplify by just getting rid of _PAGE_BIT_SWAP_TYPE. It's not like that we can simply change it: _PAGE_SWP_SOFT_DIRTY would suddenly fall into _RPAGE_RSV1, which isn't possible and would make the BUILD_BUG_ON(_PAGE_HPTEFLAGS & _PAGE_SWP_SOFT_DIRTY) angry. While at it, make it clearer which bit we're actually using for _PAGE_SWP_SOFT_DIRTY by just using the proper define and introduce and use SWP_TYPE_MASK. Signed-off-by: David Hildenbrand <redacted> --- arch/powerpc/include/asm/book3s/64/pgtable.h | 12 +++++-------
Why only BOOK3S ? Why not BOOK3E as well ? Christophe
quoted hunk ↗ jump to hunk
1 file changed, 5 insertions(+), 7 deletions(-)diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index 875730d5af40..8e98375d5c4a 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h@@ -13,7 +13,6 @@ /* * Common bits between hash and Radix page table */ -#define _PAGE_BIT_SWAP_TYPE 0 #define _PAGE_EXEC 0x00001 /* execute permission */ #define _PAGE_WRITE 0x00002 /* write access allowed */@@ -751,17 +750,16 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) * Don't have overlapping bits with _PAGE_HPTEFLAGS \ * We filter HPTEFLAGS on set_pte. \ */ \ - BUILD_BUG_ON(_PAGE_HPTEFLAGS & (0x1f << _PAGE_BIT_SWAP_TYPE)); \ + BUILD_BUG_ON(_PAGE_HPTEFLAGS & SWP_TYPE_MASK); \ BUILD_BUG_ON(_PAGE_HPTEFLAGS & _PAGE_SWP_SOFT_DIRTY); \ } while (0) #define SWP_TYPE_BITS 5 -#define __swp_type(x) (((x).val >> _PAGE_BIT_SWAP_TYPE) \ - & ((1UL << SWP_TYPE_BITS) - 1)) +#define SWP_TYPE_MASK ((1UL << SWP_TYPE_BITS) - 1) +#define __swp_type(x) ((x).val & SWP_TYPE_MASK) #define __swp_offset(x) (((x).val & PTE_RPN_MASK) >> PAGE_SHIFT) #define __swp_entry(type, offset) ((swp_entry_t) { \ - ((type) << _PAGE_BIT_SWAP_TYPE) \ - | (((offset) << PAGE_SHIFT) & PTE_RPN_MASK)}) + (type) | (((offset) << PAGE_SHIFT) & PTE_RPN_MASK)}) /* * swp_entry_t must be independent of pte bits. We build a swp_entry_t from * swap type and offset we get from swap and convert that to pte to find a@@ -774,7 +772,7 @@ static inline pte_t pte_modify(pte_t pte, pgprot_t newprot) #define __swp_entry_to_pmd(x) (pte_pmd(__swp_entry_to_pte(x))) #ifdef CONFIG_MEM_SOFT_DIRTY -#define _PAGE_SWP_SOFT_DIRTY (1UL << (SWP_TYPE_BITS + _PAGE_BIT_SWAP_TYPE)) +#define _PAGE_SWP_SOFT_DIRTY _PAGE_NON_IDEMPOTENT #else #define _PAGE_SWP_SOFT_DIRTY 0UL #endif /* CONFIG_MEM_SOFT_DIRTY */