[PATCH v2 7/8] powerpc/pgtable: remove _PAGE_BIT_SWAP_TYPE for book3s

David Hildenbrand
2022-03-29T16:50:19Z

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 <david@redhat.com>
---
arch/powerpc/include/asm/book3s/64/pgtable.h | 12 +++++-------
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 */
--
2.35.1