mirror of
https://github.com/torvalds/linux.git
synced 2024-11-01 01:31:44 +00:00
d6dd61c831
Add hooks to allow a paravirt implementation to track the lifetime of an mm. Paravirtualization requires three hooks, but only two are needed in common code. They are: arch_dup_mmap, which is called when a new mmap is created at fork arch_exit_mmap, which is called when the last process reference to an mm is dropped, which typically happens on exit and exec. The third hook is activate_mm, which is called from the arch-specific activate_mm() macro/function, and so doesn't need stub versions for other architectures. It's called when an mm is first used. Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com> Signed-off-by: Andi Kleen <ak@suse.de> Cc: linux-arch@vger.kernel.org Cc: James Bottomley <James.Bottomley@SteelEye.com> Acked-by: Ingo Molnar <mingo@elte.hu>
165 lines
4.2 KiB
C
165 lines
4.2 KiB
C
#ifndef _ASM_M32R_MMU_CONTEXT_H
|
|
#define _ASM_M32R_MMU_CONTEXT_H
|
|
#ifdef __KERNEL__
|
|
|
|
#include <asm/m32r.h>
|
|
|
|
#define MMU_CONTEXT_ASID_MASK (0x000000FF)
|
|
#define MMU_CONTEXT_VERSION_MASK (0xFFFFFF00)
|
|
#define MMU_CONTEXT_FIRST_VERSION (0x00000100)
|
|
#define NO_CONTEXT (0x00000000)
|
|
|
|
#ifndef __ASSEMBLY__
|
|
|
|
#include <asm/atomic.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/mmu.h>
|
|
#include <asm/tlbflush.h>
|
|
#include <asm-generic/mm_hooks.h>
|
|
|
|
/*
|
|
* Cache of MMU context last used.
|
|
*/
|
|
#ifndef CONFIG_SMP
|
|
extern unsigned long mmu_context_cache_dat;
|
|
#define mmu_context_cache mmu_context_cache_dat
|
|
#define mm_context(mm) mm->context
|
|
#else /* not CONFIG_SMP */
|
|
extern unsigned long mmu_context_cache_dat[];
|
|
#define mmu_context_cache mmu_context_cache_dat[smp_processor_id()]
|
|
#define mm_context(mm) mm->context[smp_processor_id()]
|
|
#endif /* not CONFIG_SMP */
|
|
|
|
#define set_tlb_tag(entry, tag) (*entry = (tag & PAGE_MASK)|get_asid())
|
|
#define set_tlb_data(entry, data) (*entry = (data | _PAGE_PRESENT))
|
|
|
|
#ifdef CONFIG_MMU
|
|
#define enter_lazy_tlb(mm, tsk) do { } while (0)
|
|
|
|
static inline void get_new_mmu_context(struct mm_struct *mm)
|
|
{
|
|
unsigned long mc = ++mmu_context_cache;
|
|
|
|
if (!(mc & MMU_CONTEXT_ASID_MASK)) {
|
|
/* We exhaust ASID of this version.
|
|
Flush all TLB and start new cycle. */
|
|
local_flush_tlb_all();
|
|
/* Fix version if needed.
|
|
Note that we avoid version #0 to distingush NO_CONTEXT. */
|
|
if (!mc)
|
|
mmu_context_cache = mc = MMU_CONTEXT_FIRST_VERSION;
|
|
}
|
|
mm_context(mm) = mc;
|
|
}
|
|
|
|
/*
|
|
* Get MMU context if needed.
|
|
*/
|
|
static inline void get_mmu_context(struct mm_struct *mm)
|
|
{
|
|
if (mm) {
|
|
unsigned long mc = mmu_context_cache;
|
|
|
|
/* Check if we have old version of context.
|
|
If it's old, we need to get new context with new version. */
|
|
if ((mm_context(mm) ^ mc) & MMU_CONTEXT_VERSION_MASK)
|
|
get_new_mmu_context(mm);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize the context related info for a new mm_struct
|
|
* instance.
|
|
*/
|
|
static inline int init_new_context(struct task_struct *tsk,
|
|
struct mm_struct *mm)
|
|
{
|
|
#ifndef CONFIG_SMP
|
|
mm->context = NO_CONTEXT;
|
|
#else /* CONFIG_SMP */
|
|
int num_cpus = num_online_cpus();
|
|
int i;
|
|
|
|
for (i = 0 ; i < num_cpus ; i++)
|
|
mm->context[i] = NO_CONTEXT;
|
|
#endif /* CONFIG_SMP */
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Destroy context related info for an mm_struct that is about
|
|
* to be put to rest.
|
|
*/
|
|
#define destroy_context(mm) do { } while (0)
|
|
|
|
static inline void set_asid(unsigned long asid)
|
|
{
|
|
*(volatile unsigned long *)MASID = (asid & MMU_CONTEXT_ASID_MASK);
|
|
}
|
|
|
|
static inline unsigned long get_asid(void)
|
|
{
|
|
unsigned long asid;
|
|
|
|
asid = *(volatile long *)MASID;
|
|
asid &= MMU_CONTEXT_ASID_MASK;
|
|
|
|
return asid;
|
|
}
|
|
|
|
/*
|
|
* 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_context(struct mm_struct *mm)
|
|
{
|
|
get_mmu_context(mm);
|
|
set_asid(mm_context(mm) & MMU_CONTEXT_ASID_MASK);
|
|
}
|
|
|
|
static inline void switch_mm(struct mm_struct *prev,
|
|
struct mm_struct *next, struct task_struct *tsk)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
int cpu = smp_processor_id();
|
|
#endif /* CONFIG_SMP */
|
|
|
|
if (prev != next) {
|
|
#ifdef CONFIG_SMP
|
|
cpu_set(cpu, next->cpu_vm_mask);
|
|
#endif /* CONFIG_SMP */
|
|
/* Set MPTB = next->pgd */
|
|
*(volatile unsigned long *)MPTB = (unsigned long)next->pgd;
|
|
activate_context(next);
|
|
}
|
|
#ifdef CONFIG_SMP
|
|
else
|
|
if (!cpu_test_and_set(cpu, next->cpu_vm_mask))
|
|
activate_context(next);
|
|
#endif /* CONFIG_SMP */
|
|
}
|
|
|
|
#define deactivate_mm(tsk, mm) do { } while (0)
|
|
|
|
#define activate_mm(prev, next) \
|
|
switch_mm((prev), (next), NULL)
|
|
|
|
#else /* not CONFIG_MMU */
|
|
#define get_mmu_context(mm) do { } while (0)
|
|
#define init_new_context(tsk,mm) (0)
|
|
#define destroy_context(mm) do { } while (0)
|
|
#define set_asid(asid) do { } while (0)
|
|
#define get_asid() (0)
|
|
#define activate_context(mm) do { } while (0)
|
|
#define switch_mm(prev,next,tsk) do { } while (0)
|
|
#define deactivate_mm(mm,tsk) do { } while (0)
|
|
#define activate_mm(prev,next) do { } while (0)
|
|
#define enter_lazy_tlb(mm,tsk) do { } while (0)
|
|
#endif /* not CONFIG_MMU */
|
|
|
|
#endif /* not __ASSEMBLY__ */
|
|
|
|
#endif /* __KERNEL__ */
|
|
#endif /* _ASM_M32R_MMU_CONTEXT_H */
|