Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
awilliam
GitHub Repository: awilliam/linux-vfio
 Path: blob/master/arch/mn10300/mm/mmu-context.c
10817 views
1
/* MN10300 MMU context allocation and management

2
 *

3
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.

4
 * Written by David Howells ([email protected])

5
 *

6
 * This program is free software; you can redistribute it and/or

7
 * modify it under the terms of the GNU General Public Licence

8
 * as published by the Free Software Foundation; either version

9
 * 2 of the Licence, or (at your option) any later version.

10
 */

11
#include <linux/sched.h>

12
#include <linux/mm.h>

13
#include <asm/mmu_context.h>

14
#include <asm/tlbflush.h>

15


16
#ifdef CONFIG_MN10300_TLB_USE_PIDR

17
/*

18
 * list of the MMU contexts last allocated on each CPU

19
 */

20
unsigned long mmu_context_cache[NR_CPUS] = {

21
	[0 ... NR_CPUS - 1] =

22
	MMU_CONTEXT_FIRST_VERSION * 2 - (1 - MMU_CONTEXT_TLBPID_LOCK_NR),

23
};

24
#endif /* CONFIG_MN10300_TLB_USE_PIDR */

25


26
/*

27
 * preemptively set a TLB entry

28
 */

29
void update_mmu_cache(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep)

30
{

31
	unsigned long pteu, ptel, cnx, flags;

32
	pte_t pte = *ptep;

33


34
	addr &= PAGE_MASK;

35
	ptel = pte_val(pte) & ~(xPTEL_UNUSED1 | xPTEL_UNUSED2);

36


37
	/* make sure the context doesn't migrate and defend against

38
	 * interference from vmalloc'd regions */

39
	local_irq_save(flags);

40


41
	cnx = ~MMU_NO_CONTEXT;

42
#ifdef CONFIG_MN10300_TLB_USE_PIDR

43
	cnx = mm_context(vma->vm_mm);

44
#endif

45


46
	if (cnx != MMU_NO_CONTEXT) {

47
		pteu = addr;

48
#ifdef CONFIG_MN10300_TLB_USE_PIDR

49
		pteu |= cnx & MMU_CONTEXT_TLBPID_MASK;

50
#endif

51
		if (!(pte_val(pte) & _PAGE_NX)) {

52
			IPTEU = pteu;

53
			if (IPTEL & xPTEL_V)

54
				IPTEL = ptel;

55
		}

56
		DPTEU = pteu;

57
		if (DPTEL & xPTEL_V)

58
			DPTEL = ptel;

59
	}

60


61
	local_irq_restore(flags);

62
}

63


64