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| author | Guo Ren <guoren@linux.alibaba.com> | 2021-01-13 15:28:16 +0800 |
|---|---|---|
| committer | Guo Ren <guoren@linux.alibaba.com> | 2021-02-27 16:32:54 +0800 |
| commit | af94002bda1d94f667706b6369ca1e718f32a072 (patch) | |
| tree | 5dda8ecb8de623c77f775fb9b778e6523410372f /arch/csky/abiv2 | |
| parent | a8fac05acf38bdd1ab5aaf86dba7d0b2b0c05dd6 (diff) | |
csky: Fixup swapon
Current csky's swappon is broken by wrong swap PTE entry format.
Now redesign the new format for abiv1 & abiv2 and make swappon +
zram work properly on csky machines.
C-SKY PTE has VALID, DIRTY to emulate PRESENT, READ, WRITE, EXEC
attributes. GLOBAL bit is shared by two pages in the same tlb
entry. So we need to keep GLOBAL, VALID, PRESENT zero in swp_pte.
To distinguish PAGE_NONE and swp_pte, we need to use an additional
bit (abiv1 is _PAGE_READ, abiv2 is _PAGE_WRITE).
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/csky/abiv2')
| -rw-r--r-- | arch/csky/abiv2/inc/abi/pgtable-bits.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/arch/csky/abiv2/inc/abi/pgtable-bits.h b/arch/csky/abiv2/inc/abi/pgtable-bits.h index 09303dbc89a6..5b27eaf18aa8 100644 --- a/arch/csky/abiv2/inc/abi/pgtable-bits.h +++ b/arch/csky/abiv2/inc/abi/pgtable-bits.h @@ -24,4 +24,26 @@ #define _CACHE_CACHED (_PAGE_CACHE | _PAGE_BUF) #define _CACHE_UNCACHED (0) +#define _PAGE_PROT_NONE _PAGE_WRITE + +/* + * Encode and decode a swap entry + * + * Format of swap PTE: + * bit 0: _PAGE_GLOBAL (zero) + * bit 1: _PAGE_VALID (zero) + * bit 2 - 6: swap type + * bit 7 - 8: swap offset[0 - 1] + * bit 9: _PAGE_WRITE (zero) + * bit 10: _PAGE_PRESENT (zero) + * bit 11 - 31: swap offset[2 - 22] + */ +#define __swp_type(x) (((x).val >> 2) & 0x1f) +#define __swp_offset(x) ((((x).val >> 7) & 0x3) | \ + (((x).val >> 9) & 0x7ffffc)) +#define __swp_entry(type, offset) ((swp_entry_t) { \ + ((type & 0x1f) << 2) | \ + ((offset & 0x3) << 7) | \ + ((offset & 0x7ffffc) << 9)}) + #endif /* __ASM_CSKY_PGTABLE_BITS_H */ |