mirror of
https://github.com/torvalds/linux.git
synced 2024-11-02 10:11:36 +00:00
250cf776f7
The current enable_sie code sets the mm->context.pgstes bit to tell dup_mm that the new mm should have extended page tables. This bit is also used by the s390 specific page table primitives to decide about the page table layout - which means context.pgstes has two meanings. This can cause any kind of bugs. For example - e.g. shrink_zone can call ptep_clear_flush_young while enable_sie is running. ptep_clear_flush_young will test for context.pgstes. Since enable_sie changed that value of the old struct mm without changing the page table layout ptep_clear_flush_young will do the wrong thing. The solution is to split pgstes into two bits - one for the allocation - one for the current state Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
91 lines
2.5 KiB
C
91 lines
2.5 KiB
C
/*
|
|
* include/asm-s390/mmu_context.h
|
|
*
|
|
* S390 version
|
|
*
|
|
* Derived from "include/asm-i386/mmu_context.h"
|
|
*/
|
|
|
|
#ifndef __S390_MMU_CONTEXT_H
|
|
#define __S390_MMU_CONTEXT_H
|
|
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/uaccess.h>
|
|
#include <asm-generic/mm_hooks.h>
|
|
|
|
static inline int init_new_context(struct task_struct *tsk,
|
|
struct mm_struct *mm)
|
|
{
|
|
mm->context.asce_bits = _ASCE_TABLE_LENGTH | _ASCE_USER_BITS;
|
|
#ifdef CONFIG_64BIT
|
|
mm->context.asce_bits |= _ASCE_TYPE_REGION3;
|
|
#endif
|
|
if (current->mm->context.alloc_pgste) {
|
|
/*
|
|
* alloc_pgste indicates, that any NEW context will be created
|
|
* with extended page tables. The old context is unchanged. The
|
|
* page table allocation and the page table operations will
|
|
* look at has_pgste to distinguish normal and extended page
|
|
* tables. The only way to create extended page tables is to
|
|
* set alloc_pgste and then create a new context (e.g. dup_mm).
|
|
* The page table allocation is called after init_new_context
|
|
* and if has_pgste is set, it will create extended page
|
|
* tables.
|
|
*/
|
|
mm->context.noexec = 0;
|
|
mm->context.has_pgste = 1;
|
|
mm->context.alloc_pgste = 1;
|
|
} else {
|
|
mm->context.noexec = s390_noexec;
|
|
mm->context.has_pgste = 0;
|
|
mm->context.alloc_pgste = 0;
|
|
}
|
|
mm->context.asce_limit = STACK_TOP_MAX;
|
|
crst_table_init((unsigned long *) mm->pgd, pgd_entry_type(mm));
|
|
return 0;
|
|
}
|
|
|
|
#define destroy_context(mm) do { } while (0)
|
|
|
|
#ifndef __s390x__
|
|
#define LCTL_OPCODE "lctl"
|
|
#else
|
|
#define LCTL_OPCODE "lctlg"
|
|
#endif
|
|
|
|
static inline void update_mm(struct mm_struct *mm, struct task_struct *tsk)
|
|
{
|
|
pgd_t *pgd = mm->pgd;
|
|
|
|
S390_lowcore.user_asce = mm->context.asce_bits | __pa(pgd);
|
|
if (switch_amode) {
|
|
/* Load primary space page table origin. */
|
|
pgd = mm->context.noexec ? get_shadow_table(pgd) : pgd;
|
|
S390_lowcore.user_exec_asce = mm->context.asce_bits | __pa(pgd);
|
|
asm volatile(LCTL_OPCODE" 1,1,%0\n"
|
|
: : "m" (S390_lowcore.user_exec_asce) );
|
|
} else
|
|
/* Load home space page table origin. */
|
|
asm volatile(LCTL_OPCODE" 13,13,%0"
|
|
: : "m" (S390_lowcore.user_asce) );
|
|
set_fs(current->thread.mm_segment);
|
|
}
|
|
|
|
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
|
|
struct task_struct *tsk)
|
|
{
|
|
cpu_set(smp_processor_id(), next->cpu_vm_mask);
|
|
update_mm(next, tsk);
|
|
}
|
|
|
|
#define enter_lazy_tlb(mm,tsk) do { } while (0)
|
|
#define deactivate_mm(tsk,mm) do { } while (0)
|
|
|
|
static inline void activate_mm(struct mm_struct *prev,
|
|
struct mm_struct *next)
|
|
{
|
|
switch_mm(prev, next, current);
|
|
}
|
|
|
|
#endif /* __S390_MMU_CONTEXT_H */
|