diff options
author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2008-02-09 12:24:37 -0500 |
---|---|---|
committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2008-02-09 12:24:41 -0500 |
commit | 6252d702c5311ce916caf75ed82e5c8245171c92 (patch) | |
tree | 3490f27b5f888ff2c1ec915d4e7201000f37a771 /arch/s390/mm/fault.c | |
parent | 5a216a20837c5f5fa1ca4b8ae8991ffd96b08e6f (diff) |
[S390] dynamic page tables.
Add support for different number of page table levels dependent
on the highest address used for a process. This will cause a 31 bit
process to use a two level page table instead of the four level page
table that is the default after the pud has been introduced. Likewise
a normal 64 bit process will use three levels instead of four. Only
if a process runs out of the 4 tera bytes which can be addressed with
a three level page table the fourth level is dynamically added. Then
the process can use up to 8 peta byte.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/mm/fault.c')
-rw-r--r-- | arch/s390/mm/fault.c | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c index 2456b52ed068..ed13d429a487 100644 --- a/arch/s390/mm/fault.c +++ b/arch/s390/mm/fault.c | |||
@@ -32,6 +32,7 @@ | |||
32 | #include <asm/system.h> | 32 | #include <asm/system.h> |
33 | #include <asm/pgtable.h> | 33 | #include <asm/pgtable.h> |
34 | #include <asm/s390_ext.h> | 34 | #include <asm/s390_ext.h> |
35 | #include <asm/mmu_context.h> | ||
35 | 36 | ||
36 | #ifndef CONFIG_64BIT | 37 | #ifndef CONFIG_64BIT |
37 | #define __FAIL_ADDR_MASK 0x7ffff000 | 38 | #define __FAIL_ADDR_MASK 0x7ffff000 |
@@ -444,6 +445,45 @@ void __kprobes do_dat_exception(struct pt_regs *regs, unsigned long error_code) | |||
444 | do_exception(regs, error_code & 0xff, 0); | 445 | do_exception(regs, error_code & 0xff, 0); |
445 | } | 446 | } |
446 | 447 | ||
448 | #ifdef CONFIG_64BIT | ||
449 | void __kprobes do_asce_exception(struct pt_regs *regs, unsigned long error_code) | ||
450 | { | ||
451 | struct mm_struct *mm; | ||
452 | struct vm_area_struct *vma; | ||
453 | unsigned long address; | ||
454 | int space; | ||
455 | |||
456 | mm = current->mm; | ||
457 | address = S390_lowcore.trans_exc_code & __FAIL_ADDR_MASK; | ||
458 | space = check_space(current); | ||
459 | |||
460 | if (unlikely(space == 0 || in_atomic() || !mm)) | ||
461 | goto no_context; | ||
462 | |||
463 | local_irq_enable(); | ||
464 | |||
465 | down_read(&mm->mmap_sem); | ||
466 | vma = find_vma(mm, address); | ||
467 | up_read(&mm->mmap_sem); | ||
468 | |||
469 | if (vma) { | ||
470 | update_mm(mm, current); | ||
471 | return; | ||
472 | } | ||
473 | |||
474 | /* User mode accesses just cause a SIGSEGV */ | ||
475 | if (regs->psw.mask & PSW_MASK_PSTATE) { | ||
476 | current->thread.prot_addr = address; | ||
477 | current->thread.trap_no = error_code; | ||
478 | do_sigsegv(regs, error_code, SEGV_MAPERR, address); | ||
479 | return; | ||
480 | } | ||
481 | |||
482 | no_context: | ||
483 | do_no_context(regs, error_code, address); | ||
484 | } | ||
485 | #endif | ||
486 | |||
447 | #ifdef CONFIG_PFAULT | 487 | #ifdef CONFIG_PFAULT |
448 | /* | 488 | /* |
449 | * 'pfault' pseudo page faults routines. | 489 | * 'pfault' pseudo page faults routines. |