[linux-2.6-block.git] / arch / blackfin / include / asm / mmu_context.h

/*
 * 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/slab.h>
#include <linux/sched.h>
#include <asm/setup.h>
#include <asm/page.h>
#include <asm/pgalloc.h>
#include <asm/cplbinit.h>
#include <asm/sections.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);
		l1_stack_base = NULL;
		l1_stack_len = 0;
	}
}

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_IPIPE
#define lock_mm_switch(flags)	flags = hard_local_irq_save_cond()
#define unlock_mm_switch(flags)	hard_local_irq_restore_cond(flags)
#else
#define lock_mm_switch(flags)	do { (void)(flags); } while (0)
#define unlock_mm_switch(flags)	do { (void)(flags); } while (0)
#endif /* CONFIG_IPIPE */

#ifdef CONFIG_MPU
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
			     struct task_struct *tsk)
{
	unsigned long flags;
	lock_mm_switch(flags);
	__switch_mm(prev, next, tsk);
	unlock_mm_switch(flags);
}

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;
	unsigned long idx;
	unsigned long bit;

	if (unlikely(addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE))
		page = (addr - (ASYNC_BANK0_BASE - _ramend)) >> 12;
	else
		page = addr >> 12;
	idx = page >> 5;
	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);
	}
}
#else /* !CONFIG_MPU */
static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
			     struct task_struct *tsk)
{
	__switch_mm(prev, next, tsk);
}
#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
}

#define ipipe_mm_switch_protect(flags)		\
	flags = hard_local_irq_save_cond()

#define ipipe_mm_switch_unprotect(flags)	\
	hard_local_irq_restore_cond(flags)

#endif
Commit	Line	Data
1394f032	1	/*
96f1050d	2	* Copyright 2004-2009 Analog Devices Inc.
1394f032	3	*
96f1050d	4	* Licensed under the GPL-2 or later.
1394f032 BW	5	*/
	6
	7	#ifndef __BLACKFIN_MMU_CONTEXT_H__
	8	#define __BLACKFIN_MMU_CONTEXT_H__
	9
5a0e3ad6	10	#include <linux/slab.h>
b97b8a99	11	#include <linux/sched.h>
1394f032 BW	12	#include <asm/setup.h>
	13	#include <asm/page.h>
	14	#include <asm/pgalloc.h>
b97b8a99	15	#include <asm/cplbinit.h>
e18e7dd3	16	#include <asm/sections.h>
1394f032	17
b8a98989 GY	18	/* Note: L1 stacks are CPU-private things, so we bluntly disable this
	19	feature in SMP mode, and use the per-CPU scratch SRAM bank only to
	20	store the PDA instead. */
	21
1394f032 BW	22	extern void *current_l1_stack_save;
	23	extern int nr_l1stack_tasks;
	24	extern void *l1_stack_base;
	25	extern unsigned long l1_stack_len;
	26
	27	extern int l1sram_free(const void*);
	28	extern void l1sram_alloc_max(void);
	29
1394f032 BW	30	static inline void free_l1stack(void)
	31	{
	32	nr_l1stack_tasks--;
edd8a97e	33	if (nr_l1stack_tasks == 0) {
1394f032	34	l1sram_free(l1_stack_base);
edd8a97e BS	35	l1_stack_base = NULL;
	36	l1_stack_len = 0;
	37	}
1394f032	38	}
1394f032 BW	39
	40	static inline unsigned long
	41	alloc_l1stack(unsigned long length, unsigned long *stack_base)
	42	{
	43	if (nr_l1stack_tasks == 0) {
	44	l1_stack_base = l1sram_alloc_max(&l1_stack_len);
	45	if (!l1_stack_base)
	46	return 0;
	47	}
	48
	49	if (l1_stack_len < length) {
	50	if (nr_l1stack_tasks == 0)
	51	l1sram_free(l1_stack_base);
	52	return 0;
	53	}
	54	*stack_base = (unsigned long)l1_stack_base;
	55	nr_l1stack_tasks++;
	56	return l1_stack_len;
	57	}
	58
	59	static inline int
	60	activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
	61	{
	62	if (current_l1_stack_save)
	63	memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
	64	mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
	65	memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
	66	return 1;
	67	}
	68
	69	#define deactivate_mm(tsk,mm) do { } while (0)
	70
b97b8a99 BS	71	#define activate_mm(prev, next) switch_mm(prev, next, NULL)
b97b8a99 BS	72
4815b883 PG	73	static inline void __switch_mm(struct mm_struct prev_mm, struct mm_struct next_mm,
4815b883 PG	74	struct task_struct *tsk)
1394f032	75	{
b8a98989 GY	76	#ifdef CONFIG_MPU
	77	unsigned int cpu = smp_processor_id();
	78	#endif
b97b8a99 BS	79	if (prev_mm == next_mm)
	80	return;
	81	#ifdef CONFIG_MPU
b8a98989 GY	82	if (prev_mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
	83	flush_switched_cplbs(cpu);
	84	set_mask_dcplbs(next_mm->context.page_rwx_mask, cpu);
b97b8a99 BS	85	}
	86	#endif
	87
ca87b7ad	88	#ifdef CONFIG_APP_STACK_L1
b97b8a99	89	/* L1 stack switching. */
1394f032 BW	90	if (!next_mm->context.l1_stack_save)
	91	return;
	92	if (next_mm->context.l1_stack_save == current_l1_stack_save)
	93	return;
	94	if (current_l1_stack_save) {
	95	memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
	96	}
	97	current_l1_stack_save = next_mm->context.l1_stack_save;
	98	memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
ca87b7ad	99	#endif
1394f032 BW	100	}
1394f032 BW	101
4815b883	102	#ifdef CONFIG_IPIPE
3b139cdb DH	103	#define lock_mm_switch(flags) flags = hard_local_irq_save_cond()
3b139cdb DH	104	#define unlock_mm_switch(flags) hard_local_irq_restore_cond(flags)
4815b883 PG	105	#else
	106	#define lock_mm_switch(flags) do { (void)(flags); } while (0)
	107	#define unlock_mm_switch(flags) do { (void)(flags); } while (0)
	108	#endif /* CONFIG_IPIPE */
	109
b97b8a99	110	#ifdef CONFIG_MPU
4815b883 PG	111	static inline void switch_mm(struct mm_struct prev, struct mm_struct next,
	112	struct task_struct *tsk)
	113	{
	114	unsigned long flags;
	115	lock_mm_switch(flags);
	116	__switch_mm(prev, next, tsk);
	117	unlock_mm_switch(flags);
	118	}
	119
b97b8a99 BS	120	static inline void protect_page(struct mm_struct *mm, unsigned long addr,
	121	unsigned long flags)
	122	{
	123	unsigned long *mask = mm->context.page_rwx_mask;
e18e7dd3 BS	124	unsigned long page;
	125	unsigned long idx;
	126	unsigned long bit;
	127
	128	if (unlikely(addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE))
	129	page = (addr - (ASYNC_BANK0_BASE - _ramend)) >> 12;
	130	else
	131	page = addr >> 12;
	132	idx = page >> 5;
	133	bit = 1 << (page & 31);
b97b8a99	134
36b84128	135	if (flags & VM_READ)
b97b8a99 BS	136	mask[idx] \|= bit;
	137	else
	138	mask[idx] &= ~bit;
	139	mask += page_mask_nelts;
36b84128	140	if (flags & VM_WRITE)
b97b8a99 BS	141	mask[idx] \|= bit;
	142	else
	143	mask[idx] &= ~bit;
	144	mask += page_mask_nelts;
36b84128	145	if (flags & VM_EXEC)
b97b8a99 BS	146	mask[idx] \|= bit;
	147	else
	148	mask[idx] &= ~bit;
	149	}
	150
	151	static inline void update_protections(struct mm_struct *mm)
1394f032	152	{
b8a98989 GY	153	unsigned int cpu = smp_processor_id();
	154	if (mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
	155	flush_switched_cplbs(cpu);
	156	set_mask_dcplbs(mm->context.page_rwx_mask, cpu);
3d9b7a5c	157	}
1394f032	158	}
4815b883 PG	159	#else /* !CONFIG_MPU */
	160	static inline void switch_mm(struct mm_struct prev, struct mm_struct next,
	161	struct task_struct *tsk)
	162	{
	163	__switch_mm(prev, next, tsk);
	164	}
b97b8a99	165	#endif
1394f032	166
ca87b7ad GY	167	static inline void enter_lazy_tlb(struct mm_struct mm, struct task_struct tsk)
	168	{
	169	}
	170
	171	/* Called when creating a new context during fork() or execve(). */
	172	static inline int
	173	init_new_context(struct task_struct tsk, struct mm_struct mm)
	174	{
	175	#ifdef CONFIG_MPU
	176	unsigned long p = __get_free_pages(GFP_KERNEL, page_mask_order);
	177	mm->context.page_rwx_mask = (unsigned long *)p;
	178	memset(mm->context.page_rwx_mask, 0,
	179	page_mask_nelts * 3 * sizeof(long));
	180	#endif
	181	return 0;
	182	}
	183
	184	static inline void destroy_context(struct mm_struct *mm)
	185	{
	186	struct sram_list_struct *tmp;
b8a98989 GY	187	#ifdef CONFIG_MPU
	188	unsigned int cpu = smp_processor_id();
	189	#endif
ca87b7ad GY	190
	191	#ifdef CONFIG_APP_STACK_L1
	192	if (current_l1_stack_save == mm->context.l1_stack_save)
	193	current_l1_stack_save = 0;
	194	if (mm->context.l1_stack_save)
	195	free_l1stack();
	196	#endif
	197
	198	while ((tmp = mm->context.sram_list)) {
	199	mm->context.sram_list = tmp->next;
	200	sram_free(tmp->addr);
	201	kfree(tmp);
	202	}
	203	#ifdef CONFIG_MPU
b8a98989 GY	204	if (current_rwx_mask[cpu] == mm->context.page_rwx_mask)
b8a98989 GY	205	current_rwx_mask[cpu] = NULL;
ca87b7ad GY	206	free_pages((unsigned long)mm->context.page_rwx_mask, page_mask_order);
	207	#endif
	208	}
	209
4815b883	210	#define ipipe_mm_switch_protect(flags) \
3b139cdb	211	flags = hard_local_irq_save_cond()
4815b883 PG	212
4815b883 PG	213	#define ipipe_mm_switch_unprotect(flags) \
3b139cdb	214	hard_local_irq_restore_cond(flags)
4815b883	215
1394f032	216	#endif