diff options
| -rw-r--r-- | arch/x86/include/asm/pgtable-2level.h | 50 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable-3level.h | 1 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable.h | 14 | ||||
| -rw-r--r-- | arch/x86/include/asm/pgtable_64.h | 20 | ||||
| -rw-r--r-- | mm/swapfile.c | 9 |
5 files changed, 75 insertions, 19 deletions
diff --git a/arch/x86/include/asm/pgtable-2level.h b/arch/x86/include/asm/pgtable-2level.h index b17edfd23628..e0d199fe1d83 100644 --- a/arch/x86/include/asm/pgtable-2level.h +++ b/arch/x86/include/asm/pgtable-2level.h @@ -56,23 +56,55 @@ static inline pte_t native_ptep_get_and_clear(pte_t *xp) #define pte_none(x) (!(x).pte_low) /* - * Bits 0, 6 and 7 are taken, split up the 29 bits of offset - * into this range: + * Bits _PAGE_BIT_PRESENT, _PAGE_BIT_FILE and _PAGE_BIT_PROTNONE are taken, + * split up the 29 bits of offset into this range: */ #define PTE_FILE_MAX_BITS 29 +#define PTE_FILE_SHIFT1 (_PAGE_BIT_PRESENT + 1) +#if _PAGE_BIT_FILE < _PAGE_BIT_PROTNONE +#define PTE_FILE_SHIFT2 (_PAGE_BIT_FILE + 1) +#define PTE_FILE_SHIFT3 (_PAGE_BIT_PROTNONE + 1) +#else +#define PTE_FILE_SHIFT2 (_PAGE_BIT_PROTNONE + 1) +#define PTE_FILE_SHIFT3 (_PAGE_BIT_FILE + 1) +#endif +#define PTE_FILE_BITS1 (PTE_FILE_SHIFT2 - PTE_FILE_SHIFT1 - 1) +#define PTE_FILE_BITS2 (PTE_FILE_SHIFT3 - PTE_FILE_SHIFT2 - 1) #define pte_to_pgoff(pte) \ - ((((pte).pte_low >> 1) & 0x1f) + (((pte).pte_low >> 8) << 5)) + ((((pte).pte_low >> PTE_FILE_SHIFT1) \ + & ((1U << PTE_FILE_BITS1) - 1)) \ + + ((((pte).pte_low >> PTE_FILE_SHIFT2) \ + & ((1U << PTE_FILE_BITS2) - 1)) << PTE_FILE_BITS1) \ + + (((pte).pte_low >> PTE_FILE_SHIFT3) \ + << (PTE_FILE_BITS1 + PTE_FILE_BITS2))) #define pgoff_to_pte(off) \ - ((pte_t) { .pte_low = (((off) & 0x1f) << 1) + \ - (((off) >> 5) << 8) + _PAGE_FILE }) + ((pte_t) { .pte_low = \ + (((off) & ((1U << PTE_FILE_BITS1) - 1)) << PTE_FILE_SHIFT1) \ + + ((((off) >> PTE_FILE_BITS1) & ((1U << PTE_FILE_BITS2) - 1)) \ + << PTE_FILE_SHIFT2) \ + + (((off) >> (PTE_FILE_BITS1 + PTE_FILE_BITS2)) \ + << PTE_FILE_SHIFT3) \ + + _PAGE_FILE }) /* Encode and de-code a swap entry */ -#define __swp_type(x) (((x).val >> 1) & 0x1f) -#define __swp_offset(x) ((x).val >> 8) -#define __swp_entry(type, offset) \ - ((swp_entry_t) { ((type) << 1) | ((offset) << 8) }) +#if _PAGE_BIT_FILE < _PAGE_BIT_PROTNONE +#define SWP_TYPE_BITS (_PAGE_BIT_FILE - _PAGE_BIT_PRESENT - 1) +#define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1) +#else +#define SWP_TYPE_BITS (_PAGE_BIT_PROTNONE - _PAGE_BIT_PRESENT - 1) +#define SWP_OFFSET_SHIFT (_PAGE_BIT_FILE + 1) +#endif + +#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS) + +#define __swp_type(x) (((x).val >> (_PAGE_BIT_PRESENT + 1)) \ + & ((1U << SWP_TYPE_BITS) - 1)) +#define __swp_offset(x) ((x).val >> SWP_OFFSET_SHIFT) +#define __swp_entry(type, offset) ((swp_entry_t) { \ + ((type) << (_PAGE_BIT_PRESENT + 1)) \ + | ((offset) << SWP_OFFSET_SHIFT) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { (pte).pte_low }) #define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val }) diff --git a/arch/x86/include/asm/pgtable-3level.h b/arch/x86/include/asm/pgtable-3level.h index 52597aeadfff..447da43cddb3 100644 --- a/arch/x86/include/asm/pgtable-3level.h +++ b/arch/x86/include/asm/pgtable-3level.h @@ -166,6 +166,7 @@ static inline int pte_none(pte_t pte) #define PTE_FILE_MAX_BITS 32 /* Encode and de-code a swap entry */ +#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > 5) #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}) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index c012f3b11671..b7c2ecdb7658 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -10,7 +10,6 @@ #define _PAGE_BIT_PCD 4 /* page cache disabled */ #define _PAGE_BIT_ACCESSED 5 /* was accessed (raised by CPU) */ #define _PAGE_BIT_DIRTY 6 /* was written to (raised by CPU) */ -#define _PAGE_BIT_FILE 6 #define _PAGE_BIT_PSE 7 /* 4 MB (or 2MB) page */ #define _PAGE_BIT_PAT 7 /* on 4KB pages */ #define _PAGE_BIT_GLOBAL 8 /* Global TLB entry PPro+ */ @@ -22,6 +21,12 @@ #define _PAGE_BIT_CPA_TEST _PAGE_BIT_UNUSED1 #define _PAGE_BIT_NX 63 /* No execute: only valid after cpuid check */ +/* If _PAGE_BIT_PRESENT is clear, we use these: */ +/* - if the user mapped it with PROT_NONE; pte_present gives true */ +#define _PAGE_BIT_PROTNONE _PAGE_BIT_GLOBAL +/* - set: nonlinear file mapping, saved PTE; unset:swap */ +#define _PAGE_BIT_FILE _PAGE_BIT_DIRTY + #define _PAGE_PRESENT (_AT(pteval_t, 1) << _PAGE_BIT_PRESENT) #define _PAGE_RW (_AT(pteval_t, 1) << _PAGE_BIT_RW) #define _PAGE_USER (_AT(pteval_t, 1) << _PAGE_BIT_USER) @@ -46,11 +51,8 @@ #define _PAGE_NX (_AT(pteval_t, 0)) #endif -/* If _PAGE_PRESENT is clear, we use these: */ -#define _PAGE_FILE _PAGE_DIRTY /* nonlinear file mapping, - * saved PTE; unset:swap */ -#define _PAGE_PROTNONE _PAGE_PSE /* if the user mapped it with PROT_NONE; - pte_present gives true */ +#define _PAGE_FILE (_AT(pteval_t, 1) << _PAGE_BIT_FILE) +#define _PAGE_PROTNONE (_AT(pteval_t, 1) << _PAGE_BIT_PROTNONE) #define _PAGE_TABLE (_PAGE_PRESENT | _PAGE_RW | _PAGE_USER | \ _PAGE_ACCESSED | _PAGE_DIRTY) diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 545a0e042bb2..65b6be6677c7 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -250,10 +250,22 @@ static inline int pud_large(pud_t pte) extern int direct_gbpages; /* Encode and de-code a swap entry */ -#define __swp_type(x) (((x).val >> 1) & 0x3f) -#define __swp_offset(x) ((x).val >> 8) -#define __swp_entry(type, offset) ((swp_entry_t) { ((type) << 1) | \ - ((offset) << 8) }) +#if _PAGE_BIT_FILE < _PAGE_BIT_PROTNONE +#define SWP_TYPE_BITS (_PAGE_BIT_FILE - _PAGE_BIT_PRESENT - 1) +#define SWP_OFFSET_SHIFT (_PAGE_BIT_PROTNONE + 1) +#else +#define SWP_TYPE_BITS (_PAGE_BIT_PROTNONE - _PAGE_BIT_PRESENT - 1) +#define SWP_OFFSET_SHIFT (_PAGE_BIT_FILE + 1) +#endif + +#define MAX_SWAPFILES_CHECK() BUILD_BUG_ON(MAX_SWAPFILES_SHIFT > SWP_TYPE_BITS) + +#define __swp_type(x) (((x).val >> (_PAGE_BIT_PRESENT + 1)) \ + & ((1U << SWP_TYPE_BITS) - 1)) +#define __swp_offset(x) ((x).val >> SWP_OFFSET_SHIFT) +#define __swp_entry(type, offset) ((swp_entry_t) { \ + ((type) << (_PAGE_BIT_PRESENT + 1)) \ + | ((offset) << SWP_OFFSET_SHIFT) }) #define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val((pte)) }) #define __swp_entry_to_pte(x) ((pte_t) { .pte = (x).val }) diff --git a/mm/swapfile.c b/mm/swapfile.c index 90cb67a5417c..54a9f87e5162 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1462,6 +1462,15 @@ static int __init procswaps_init(void) __initcall(procswaps_init); #endif /* CONFIG_PROC_FS */ +#ifdef MAX_SWAPFILES_CHECK +static int __init max_swapfiles_check(void) +{ + MAX_SWAPFILES_CHECK(); + return 0; +} +late_initcall(max_swapfiles_check); +#endif + /* * Written 01/25/92 by Simmule Turner, heavily changed by Linus. * |