linux/arch/powerpc/include/asm/mmu_context.h
Laurent Dufour 83d3f0e90c powerpc/mm: tracking vDSO remap
Some processes (CRIU) are moving the vDSO area using the mremap system
call.  As a consequence the kernel reference to the vDSO base address is
no more valid and the signal return frame built once the vDSO has been
moved is not pointing to the new sigreturn address.

This patch handles vDSO remapping and unmapping.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Rik van Riel <riel@redhat.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-24 17:49:41 -07:00

153 lines
4.4 KiB
C

#ifndef __ASM_POWERPC_MMU_CONTEXT_H
#define __ASM_POWERPC_MMU_CONTEXT_H
#ifdef __KERNEL__
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/sched.h>
#include <linux/spinlock.h>
#include <asm/mmu.h>
#include <asm/cputable.h>
#include <asm/cputhreads.h>
/*
* Most if the context management is out of line
*/
extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
extern void destroy_context(struct mm_struct *mm);
#ifdef CONFIG_SPAPR_TCE_IOMMU
struct mm_iommu_table_group_mem_t;
extern bool mm_iommu_preregistered(void);
extern long mm_iommu_get(unsigned long ua, unsigned long entries,
struct mm_iommu_table_group_mem_t **pmem);
extern long mm_iommu_put(struct mm_iommu_table_group_mem_t *mem);
extern void mm_iommu_init(mm_context_t *ctx);
extern void mm_iommu_cleanup(mm_context_t *ctx);
extern struct mm_iommu_table_group_mem_t *mm_iommu_lookup(unsigned long ua,
unsigned long size);
extern struct mm_iommu_table_group_mem_t *mm_iommu_find(unsigned long ua,
unsigned long entries);
extern long mm_iommu_ua_to_hpa(struct mm_iommu_table_group_mem_t *mem,
unsigned long ua, unsigned long *hpa);
extern long mm_iommu_mapped_inc(struct mm_iommu_table_group_mem_t *mem);
extern void mm_iommu_mapped_dec(struct mm_iommu_table_group_mem_t *mem);
#endif
extern void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next);
extern void switch_slb(struct task_struct *tsk, struct mm_struct *mm);
extern void set_context(unsigned long id, pgd_t *pgd);
#ifdef CONFIG_PPC_BOOK3S_64
extern int __init_new_context(void);
extern void __destroy_context(int context_id);
static inline void mmu_context_init(void) { }
#else
extern unsigned long __init_new_context(void);
extern void __destroy_context(unsigned long context_id);
extern void mmu_context_init(void);
#endif
extern void switch_cop(struct mm_struct *next);
extern int use_cop(unsigned long acop, struct mm_struct *mm);
extern void drop_cop(unsigned long acop, struct mm_struct *mm);
/*
* switch_mm is the entry point called from the architecture independent
* code in kernel/sched/core.c
*/
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
/* Mark this context has been used on the new CPU */
cpumask_set_cpu(smp_processor_id(), mm_cpumask(next));
/* 32-bit keeps track of the current PGDIR in the thread struct */
#ifdef CONFIG_PPC32
tsk->thread.pgdir = next->pgd;
#endif /* CONFIG_PPC32 */
/* 64-bit Book3E keeps track of current PGD in the PACA */
#ifdef CONFIG_PPC_BOOK3E_64
get_paca()->pgd = next->pgd;
#endif
/* Nothing else to do if we aren't actually switching */
if (prev == next)
return;
#ifdef CONFIG_PPC_ICSWX
/* Switch coprocessor context only if prev or next uses a coprocessor */
if (prev->context.acop || next->context.acop)
switch_cop(next);
#endif /* CONFIG_PPC_ICSWX */
/* We must stop all altivec streams before changing the HW
* context
*/
#ifdef CONFIG_ALTIVEC
if (cpu_has_feature(CPU_FTR_ALTIVEC))
asm volatile ("dssall");
#endif /* CONFIG_ALTIVEC */
/* The actual HW switching method differs between the various
* sub architectures.
*/
#ifdef CONFIG_PPC_STD_MMU_64
switch_slb(tsk, next);
#else
/* Out of line for now */
switch_mmu_context(prev, next);
#endif
}
#define deactivate_mm(tsk,mm) do { } while (0)
/*
* After we have set current->mm to a new value, this activates
* the context for the new mm so we see the new mappings.
*/
static inline void activate_mm(struct mm_struct *prev, struct mm_struct *next)
{
unsigned long flags;
local_irq_save(flags);
switch_mm(prev, next, current);
local_irq_restore(flags);
}
/* We don't currently use enter_lazy_tlb() for anything */
static inline void enter_lazy_tlb(struct mm_struct *mm,
struct task_struct *tsk)
{
/* 64-bit Book3E keeps track of current PGD in the PACA */
#ifdef CONFIG_PPC_BOOK3E_64
get_paca()->pgd = NULL;
#endif
}
static inline void arch_dup_mmap(struct mm_struct *oldmm,
struct mm_struct *mm)
{
}
static inline void arch_exit_mmap(struct mm_struct *mm)
{
}
static inline void arch_unmap(struct mm_struct *mm,
struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if (start <= mm->context.vdso_base && mm->context.vdso_base < end)
mm->context.vdso_base = 0;
}
static inline void arch_bprm_mm_init(struct mm_struct *mm,
struct vm_area_struct *vma)
{
}
#endif /* __KERNEL__ */
#endif /* __ASM_POWERPC_MMU_CONTEXT_H */