diff options
| author |   Ingo Molnar <mingo@elte.hu> | 2009-02-20 22:12:18 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-02-21 00:09:41 +0100 |
| commit | 8c938f9fae887f6e180bf802aa1c33cf74712aff (patch) | |
| tree | 3912cb11487815aa870e579ffd76f0b3fbde89a3 /arch/x86/mm/fault.c | |
| parent | x86, mm: fault.c, refactor/simplify the is_prefetch() code (diff) | |
| download | linux-dev-8c938f9fae887f6e180bf802aa1c33cf74712aff.tar.xz linux-dev-8c938f9fae887f6e180bf802aa1c33cf74712aff.zip | |
x86, mm: fault.c, factor out the vm86 fault check
Impact: cleanup
Instead of an ugly, open-coded, #ifdef-ed vm86 related legacy check
in do_page_fault(), put it into the check_v8086_mode() helper
function and merge it with an existing #ifdef.
Also, simplify the code flow a tiny bit in the helper.
No code changed:
arch/x86/mm/fault.o:
text data bss dec hex filename
2711 12 12 2735 aaf fault.o.before
2711 12 12 2735 aaf fault.o.after
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/mm/fault.c')
| -rw-r--r-- | arch/x86/mm/fault.c | 43 |
1 files changed, 31 insertions, 12 deletions
diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c index 72973c7682ba..7dc0615c3cfe 100644 --- a/arch/x86/mm/fault.c +++ b/arch/x86/mm/fault.c @@ -328,14 +328,41 @@ static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address) return pmd_k; } -#endif -#ifdef CONFIG_X86_64 +/* + * Did it hit the DOS screen memory VA from vm86 mode? + */ +static inline void +check_v8086_mode(struct pt_regs *regs, unsigned long address, + struct task_struct *tsk) +{ + unsigned long bit; + + if (!v8086_mode(regs)) + return; + + bit = (address - 0xA0000) >> PAGE_SHIFT; + if (bit < 32) + tsk->thread.screen_bitmap |= 1 << bit; +} + +#else /* CONFIG_X86_64: */ + static const char errata93_warning[] = KERN_ERR "******* Your BIOS seems to not contain a fix for K8 errata #93\n" KERN_ERR "******* Working around it, but it may cause SEGVs or burn power.\n" KERN_ERR "******* Please consider a BIOS update.\n" KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n"; + +/* + * No vm86 mode in 64-bit mode: + */ +static inline void +check_v8086_mode(struct pt_regs *regs, unsigned long address, + struct task_struct *tsk) +{ +} + #endif /* @@ -1091,16 +1118,8 @@ good_area: else tsk->min_flt++; -#ifdef CONFIG_X86_32 - /* - * Did it hit the DOS screen memory VA from vm86 mode? - */ - if (v8086_mode(regs)) { - unsigned long bit = (address - 0xA0000) >> PAGE_SHIFT; - if (bit < 32) - tsk->thread.screen_bitmap |= 1 << bit; - } -#endif + check_v8086_mode(regs, address, tsk); + up_read(&mm->mmap_sem); } |