177 lines
4.2 KiB
C
177 lines
4.2 KiB
C
/*
|
|
* Copyright 2004-2009 Analog Devices Inc.
|
|
*
|
|
* Licensed under the GPL-2 or later.
|
|
*/
|
|
|
|
#ifndef __BLACKFIN_MMU_CONTEXT_H__
|
|
#define __BLACKFIN_MMU_CONTEXT_H__
|
|
|
|
#include <linux/gfp.h>
|
|
#include <linux/sched.h>
|
|
#include <asm/setup.h>
|
|
#include <asm/page.h>
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/cplbinit.h>
|
|
|
|
/* Note: L1 stacks are CPU-private things, so we bluntly disable this
|
|
feature in SMP mode, and use the per-CPU scratch SRAM bank only to
|
|
store the PDA instead. */
|
|
|
|
extern void *current_l1_stack_save;
|
|
extern int nr_l1stack_tasks;
|
|
extern void *l1_stack_base;
|
|
extern unsigned long l1_stack_len;
|
|
|
|
extern int l1sram_free(const void*);
|
|
extern void *l1sram_alloc_max(void*);
|
|
|
|
static inline void free_l1stack(void)
|
|
{
|
|
nr_l1stack_tasks--;
|
|
if (nr_l1stack_tasks == 0)
|
|
l1sram_free(l1_stack_base);
|
|
}
|
|
|
|
static inline unsigned long
|
|
alloc_l1stack(unsigned long length, unsigned long *stack_base)
|
|
{
|
|
if (nr_l1stack_tasks == 0) {
|
|
l1_stack_base = l1sram_alloc_max(&l1_stack_len);
|
|
if (!l1_stack_base)
|
|
return 0;
|
|
}
|
|
|
|
if (l1_stack_len < length) {
|
|
if (nr_l1stack_tasks == 0)
|
|
l1sram_free(l1_stack_base);
|
|
return 0;
|
|
}
|
|
*stack_base = (unsigned long)l1_stack_base;
|
|
nr_l1stack_tasks++;
|
|
return l1_stack_len;
|
|
}
|
|
|
|
static inline int
|
|
activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
|
|
{
|
|
if (current_l1_stack_save)
|
|
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
|
|
mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
|
|
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
|
|
return 1;
|
|
}
|
|
|
|
#define deactivate_mm(tsk,mm) do { } while (0)
|
|
|
|
#define activate_mm(prev, next) switch_mm(prev, next, NULL)
|
|
|
|
static inline void switch_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm,
|
|
struct task_struct *tsk)
|
|
{
|
|
#ifdef CONFIG_MPU
|
|
unsigned int cpu = smp_processor_id();
|
|
#endif
|
|
if (prev_mm == next_mm)
|
|
return;
|
|
#ifdef CONFIG_MPU
|
|
if (prev_mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
|
|
flush_switched_cplbs(cpu);
|
|
set_mask_dcplbs(next_mm->context.page_rwx_mask, cpu);
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_APP_STACK_L1
|
|
/* L1 stack switching. */
|
|
if (!next_mm->context.l1_stack_save)
|
|
return;
|
|
if (next_mm->context.l1_stack_save == current_l1_stack_save)
|
|
return;
|
|
if (current_l1_stack_save) {
|
|
memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
|
|
}
|
|
current_l1_stack_save = next_mm->context.l1_stack_save;
|
|
memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
|
|
#endif
|
|
}
|
|
|
|
#ifdef CONFIG_MPU
|
|
static inline void protect_page(struct mm_struct *mm, unsigned long addr,
|
|
unsigned long flags)
|
|
{
|
|
unsigned long *mask = mm->context.page_rwx_mask;
|
|
unsigned long page = addr >> 12;
|
|
unsigned long idx = page >> 5;
|
|
unsigned long bit = 1 << (page & 31);
|
|
|
|
if (flags & VM_READ)
|
|
mask[idx] |= bit;
|
|
else
|
|
mask[idx] &= ~bit;
|
|
mask += page_mask_nelts;
|
|
if (flags & VM_WRITE)
|
|
mask[idx] |= bit;
|
|
else
|
|
mask[idx] &= ~bit;
|
|
mask += page_mask_nelts;
|
|
if (flags & VM_EXEC)
|
|
mask[idx] |= bit;
|
|
else
|
|
mask[idx] &= ~bit;
|
|
}
|
|
|
|
static inline void update_protections(struct mm_struct *mm)
|
|
{
|
|
unsigned int cpu = smp_processor_id();
|
|
if (mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
|
|
flush_switched_cplbs(cpu);
|
|
set_mask_dcplbs(mm->context.page_rwx_mask, cpu);
|
|
}
|
|
}
|
|
#endif
|
|
|
|
static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
|
|
{
|
|
}
|
|
|
|
/* Called when creating a new context during fork() or execve(). */
|
|
static inline int
|
|
init_new_context(struct task_struct *tsk, struct mm_struct *mm)
|
|
{
|
|
#ifdef CONFIG_MPU
|
|
unsigned long p = __get_free_pages(GFP_KERNEL, page_mask_order);
|
|
mm->context.page_rwx_mask = (unsigned long *)p;
|
|
memset(mm->context.page_rwx_mask, 0,
|
|
page_mask_nelts * 3 * sizeof(long));
|
|
#endif
|
|
return 0;
|
|
}
|
|
|
|
static inline void destroy_context(struct mm_struct *mm)
|
|
{
|
|
struct sram_list_struct *tmp;
|
|
#ifdef CONFIG_MPU
|
|
unsigned int cpu = smp_processor_id();
|
|
#endif
|
|
|
|
#ifdef CONFIG_APP_STACK_L1
|
|
if (current_l1_stack_save == mm->context.l1_stack_save)
|
|
current_l1_stack_save = 0;
|
|
if (mm->context.l1_stack_save)
|
|
free_l1stack();
|
|
#endif
|
|
|
|
while ((tmp = mm->context.sram_list)) {
|
|
mm->context.sram_list = tmp->next;
|
|
sram_free(tmp->addr);
|
|
kfree(tmp);
|
|
}
|
|
#ifdef CONFIG_MPU
|
|
if (current_rwx_mask[cpu] == mm->context.page_rwx_mask)
|
|
current_rwx_mask[cpu] = NULL;
|
|
free_pages((unsigned long)mm->context.page_rwx_mask, page_mask_order);
|
|
#endif
|
|
}
|
|
|
|
#endif
|