https://github.com/torvalds/linux
Tip revision: 08895a8b6b06ed2323cd97a36ee40a116b3db8ed authored by Linus Torvalds on 26 September 2016, 01:47:13 UTC
Linux 4.8-rc8
Linux 4.8-rc8
Tip revision: 08895a8
mmu_context.h
#ifndef __METAG_MMU_CONTEXT_H
#define __METAG_MMU_CONTEXT_H
#include <asm-generic/mm_hooks.h>
#include <asm/page.h>
#include <asm/mmu.h>
#include <asm/tlbflush.h>
#include <asm/cacheflush.h>
#include <linux/io.h>
static inline void enter_lazy_tlb(struct mm_struct *mm,
struct task_struct *tsk)
{
}
static inline int init_new_context(struct task_struct *tsk,
struct mm_struct *mm)
{
#ifndef CONFIG_METAG_META21_MMU
/* We use context to store a pointer to the page holding the
* pgd of a process while it is running. While a process is not
* running the pgd and context fields should be equal.
*/
mm->context.pgd_base = (unsigned long) mm->pgd;
#endif
#ifdef CONFIG_METAG_USER_TCM
INIT_LIST_HEAD(&mm->context.tcm);
#endif
return 0;
}
#ifdef CONFIG_METAG_USER_TCM
#include <linux/slab.h>
#include <asm/tcm.h>
static inline void destroy_context(struct mm_struct *mm)
{
struct tcm_allocation *pos, *n;
list_for_each_entry_safe(pos, n, &mm->context.tcm, list) {
tcm_free(pos->tag, pos->addr, pos->size);
list_del(&pos->list);
kfree(pos);
}
}
#else
#define destroy_context(mm) do { } while (0)
#endif
#ifdef CONFIG_METAG_META21_MMU
static inline void load_pgd(pgd_t *pgd, int thread)
{
unsigned long phys0 = mmu_phys0_addr(thread);
unsigned long phys1 = mmu_phys1_addr(thread);
/*
* 0x900 2Gb address space
* The permission bits apply to MMU table region which gives a 2MB
* window into physical memory. We especially don't want userland to be
* able to access this.
*/
metag_out32(0x900 | _PAGE_CACHEABLE | _PAGE_PRIV | _PAGE_WRITE |
_PAGE_PRESENT, phys0);
/* Set new MMU base address */
metag_out32(__pa(pgd) & MMCU_TBLPHYS1_ADDR_BITS, phys1);
}
#endif
static inline void switch_mmu(struct mm_struct *prev, struct mm_struct *next)
{
#ifdef CONFIG_METAG_META21_MMU
load_pgd(next->pgd, hard_processor_id());
#else
unsigned int i;
/* prev->context == prev->pgd in the case where we are initially
switching from the init task to the first process. */
if (prev->context.pgd_base != (unsigned long) prev->pgd) {
for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
((pgd_t *) prev->context.pgd_base)[i] = prev->pgd[i];
} else
prev->pgd = (pgd_t *)mmu_get_base();
next->pgd = prev->pgd;
prev->pgd = (pgd_t *) prev->context.pgd_base;
for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
next->pgd[i] = ((pgd_t *) next->context.pgd_base)[i];
flush_cache_all();
#endif
flush_tlb_all();
}
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
struct task_struct *tsk)
{
if (prev != next)
switch_mmu(prev, next);
}
static inline void activate_mm(struct mm_struct *prev_mm,
struct mm_struct *next_mm)
{
switch_mmu(prev_mm, next_mm);
}
#define deactivate_mm(tsk, mm) do { } while (0)
#endif