diff options
Diffstat (limited to 'arch/sh/include/asm/pgtable_32.h')
| -rw-r--r-- | arch/sh/include/asm/pgtable_32.h | 53 |
1 files changed, 41 insertions, 12 deletions
diff --git a/arch/sh/include/asm/pgtable_32.h b/arch/sh/include/asm/pgtable_32.h index d0240decacca..21952b094650 100644 --- a/arch/sh/include/asm/pgtable_32.h +++ b/arch/sh/include/asm/pgtable_32.h @@ -423,40 +423,69 @@ static inline unsigned long pmd_page_vaddr(pmd_t pmd) #endif /* - * Encode and de-code a swap entry + * Encode/decode swap entries and swap PTEs. Swap PTEs are all PTEs that + * are !pte_none() && !pte_present(). * * Constraints: * _PAGE_PRESENT at bit 8 * _PAGE_PROTNONE at bit 9 * - * For the normal case, we encode the swap type into bits 0:7 and the - * swap offset into bits 10:30. For the 64-bit PTE case, we keep the - * preserved bits in the low 32-bits and use the upper 32 as the swap - * offset (along with a 5-bit type), following the same approach as x86 - * PAE. This keeps the logic quite simple. + * For the normal case, we encode the swap type and offset into the swap PTE + * such that bits 8 and 9 stay zero. For the 64-bit PTE case, we use the + * upper 32 for the swap offset and swap type, following the same approach as + * x86 PAE. This keeps the logic quite simple. * * As is evident by the Alpha code, if we ever get a 64-bit unsigned * long (swp_entry_t) to match up with the 64-bit PTEs, this all becomes * much cleaner.. - * - * NOTE: We should set ZEROs at the position of _PAGE_PRESENT - * and _PAGE_PROTNONE bits */ + #ifdef CONFIG_X2TLB +/* + * Format of swap PTEs: + * + * 6 6 6 6 5 5 5 5 5 5 5 5 5 5 4 4 4 4 4 4 4 4 4 4 3 3 3 3 3 3 3 3 + * 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 + * <--------------------- offset ----------------------> < type -> + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <------------------- zeroes --------------------> E 0 0 0 0 0 0 + */ #define __swp_type(x) ((x).val & 0x1f) #define __swp_offset(x) ((x).val >> 5) -#define __swp_entry(type, offset) ((swp_entry_t){ (type) | (offset) << 5}) +#define __swp_entry(type, offset) ((swp_entry_t){ ((type) & 0x1f) | (offset) << 5}) #define __pte_to_swp_entry(pte) ((swp_entry_t){ (pte).pte_high }) #define __swp_entry_to_pte(x) ((pte_t){ 0, (x).val }) #else -#define __swp_type(x) ((x).val & 0xff) +/* + * Format of swap PTEs: + * + * 3 3 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1 1 1 1 1 1 + * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + * <--------------- offset ----------------> 0 0 0 0 E < type -> 0 + * + * E is the exclusive marker that is not stored in swap entries. + */ +#define __swp_type(x) ((x).val & 0x1f) #define __swp_offset(x) ((x).val >> 10) -#define __swp_entry(type, offset) ((swp_entry_t){(type) | (offset) <<10}) +#define __swp_entry(type, offset) ((swp_entry_t){((type) & 0x1f) | (offset) << 10}) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) >> 1 }) #define __swp_entry_to_pte(x) ((pte_t) { (x).val << 1 }) #endif +/* In both cases, we borrow bit 6 to store the exclusive marker in swap PTEs. */ +#define _PAGE_SWP_EXCLUSIVE _PAGE_USER + +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte.pte_low & _PAGE_SWP_EXCLUSIVE; +} + +PTE_BIT_FUNC(low, swp_mkexclusive, |= _PAGE_SWP_EXCLUSIVE); +PTE_BIT_FUNC(low, swp_clear_exclusive, &= ~_PAGE_SWP_EXCLUSIVE); + #endif /* __ASSEMBLY__ */ #endif /* __ASM_SH_PGTABLE_32_H */ |