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

/*
 * File:         include/asm-blackfin/mmu_context.h
 * Based on:
 * Author:
 *
 * Created:
 * Description:
 *
 * Modified:
 *               Copyright 2004-2006 Analog Devices Inc.
 *
 * Bugs:         Enter bugs at http://blackfin.uclinux.org/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see the file COPYING, or write
 * to the Free Software Foundation, Inc.,
 * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#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_MAYREAD)
		mask[idx] |= bit;
	else
		mask[idx] &= ~bit;
	mask += page_mask_nelts;
	if (flags & VM_MAYWRITE)
		mask[idx] |= bit;
	else
		mask[idx] &= ~bit;
	mask += page_mask_nelts;
	if (flags & VM_MAYEXEC)
		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
Commit	Line	Data
1394f032 BW	1	/*
	2	* File: include/asm-blackfin/mmu_context.h
	3	* Based on:
	4	* Author:
	5	*
	6	* Created:
	7	* Description:
	8	*
	9	* Modified:
	10	* Copyright 2004-2006 Analog Devices Inc.
	11	*
	12	* Bugs: Enter bugs at http://blackfin.uclinux.org/
	13	*
	14	* This program is free software; you can redistribute it and/or modify
	15	* it under the terms of the GNU General Public License as published by
	16	* the Free Software Foundation; either version 2 of the License, or
	17	* (at your option) any later version.
	18	*
	19	* This program is distributed in the hope that it will be useful,
	20	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	* GNU General Public License for more details.
	23	*
	24	* You should have received a copy of the GNU General Public License
	25	* along with this program; if not, see the file COPYING, or write
	26	* to the Free Software Foundation, Inc.,
	27	* 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
	28	*/
	29
	30	#ifndef __BLACKFIN_MMU_CONTEXT_H__
	31	#define __BLACKFIN_MMU_CONTEXT_H__
	32
b97b8a99 BS	33	#include <linux/gfp.h>
b97b8a99 BS	34	#include <linux/sched.h>
1394f032 BW	35	#include <asm/setup.h>
	36	#include <asm/page.h>
	37	#include <asm/pgalloc.h>
b97b8a99	38	#include <asm/cplbinit.h>
1394f032	39
b8a98989 GY	40	/* Note: L1 stacks are CPU-private things, so we bluntly disable this
	41	feature in SMP mode, and use the per-CPU scratch SRAM bank only to
	42	store the PDA instead. */
	43
1394f032 BW	44	extern void *current_l1_stack_save;
	45	extern int nr_l1stack_tasks;
	46	extern void *l1_stack_base;
	47	extern unsigned long l1_stack_len;
	48
	49	extern int l1sram_free(const void*);
	50	extern void l1sram_alloc_max(void);
	51
1394f032 BW	52	static inline void free_l1stack(void)
	53	{
	54	nr_l1stack_tasks--;
	55	if (nr_l1stack_tasks == 0)
	56	l1sram_free(l1_stack_base);
	57	}
1394f032 BW	58
	59	static inline unsigned long
	60	alloc_l1stack(unsigned long length, unsigned long *stack_base)
	61	{
	62	if (nr_l1stack_tasks == 0) {
	63	l1_stack_base = l1sram_alloc_max(&l1_stack_len);
	64	if (!l1_stack_base)
	65	return 0;
	66	}
	67
	68	if (l1_stack_len < length) {
	69	if (nr_l1stack_tasks == 0)
	70	l1sram_free(l1_stack_base);
	71	return 0;
	72	}
	73	*stack_base = (unsigned long)l1_stack_base;
	74	nr_l1stack_tasks++;
	75	return l1_stack_len;
	76	}
	77
	78	static inline int
	79	activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
	80	{
	81	if (current_l1_stack_save)
	82	memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
	83	mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
	84	memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
	85	return 1;
	86	}
	87
	88	#define deactivate_mm(tsk,mm) do { } while (0)
	89
b97b8a99 BS	90	#define activate_mm(prev, next) switch_mm(prev, next, NULL)
	91
	92	static inline void switch_mm(struct mm_struct prev_mm, struct mm_struct next_mm,
	93	struct task_struct *tsk)
1394f032	94	{
b8a98989 GY	95	#ifdef CONFIG_MPU
	96	unsigned int cpu = smp_processor_id();
	97	#endif
b97b8a99 BS	98	if (prev_mm == next_mm)
	99	return;
	100	#ifdef CONFIG_MPU
b8a98989 GY	101	if (prev_mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
	102	flush_switched_cplbs(cpu);
	103	set_mask_dcplbs(next_mm->context.page_rwx_mask, cpu);
b97b8a99 BS	104	}
	105	#endif
	106
ca87b7ad	107	#ifdef CONFIG_APP_STACK_L1
b97b8a99	108	/* L1 stack switching. */
1394f032 BW	109	if (!next_mm->context.l1_stack_save)
	110	return;
	111	if (next_mm->context.l1_stack_save == current_l1_stack_save)
	112	return;
	113	if (current_l1_stack_save) {
	114	memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
	115	}
	116	current_l1_stack_save = next_mm->context.l1_stack_save;
	117	memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
ca87b7ad	118	#endif
1394f032 BW	119	}
1394f032 BW	120
b97b8a99 BS	121	#ifdef CONFIG_MPU
	122	static inline void protect_page(struct mm_struct *mm, unsigned long addr,
	123	unsigned long flags)
	124	{
	125	unsigned long *mask = mm->context.page_rwx_mask;
	126	unsigned long page = addr >> 12;
	127	unsigned long idx = page >> 5;
	128	unsigned long bit = 1 << (page & 31);
	129
	130	if (flags & VM_MAYREAD)
	131	mask[idx] \|= bit;
	132	else
	133	mask[idx] &= ~bit;
	134	mask += page_mask_nelts;
	135	if (flags & VM_MAYWRITE)
	136	mask[idx] \|= bit;
	137	else
	138	mask[idx] &= ~bit;
	139	mask += page_mask_nelts;
	140	if (flags & VM_MAYEXEC)
	141	mask[idx] \|= bit;
	142	else
	143	mask[idx] &= ~bit;
	144	}
	145
	146	static inline void update_protections(struct mm_struct *mm)
1394f032	147	{
b8a98989 GY	148	unsigned int cpu = smp_processor_id();
	149	if (mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
	150	flush_switched_cplbs(cpu);
	151	set_mask_dcplbs(mm->context.page_rwx_mask, cpu);
3d9b7a5c	152	}
1394f032	153	}
b97b8a99	154	#endif
1394f032	155
ca87b7ad GY	156	static inline void enter_lazy_tlb(struct mm_struct mm, struct task_struct tsk)
	157	{
	158	}
	159
	160	/* Called when creating a new context during fork() or execve(). */
	161	static inline int
	162	init_new_context(struct task_struct tsk, struct mm_struct mm)
	163	{
	164	#ifdef CONFIG_MPU
	165	unsigned long p = __get_free_pages(GFP_KERNEL, page_mask_order);
	166	mm->context.page_rwx_mask = (unsigned long *)p;
	167	memset(mm->context.page_rwx_mask, 0,
	168	page_mask_nelts * 3 * sizeof(long));
	169	#endif
	170	return 0;
	171	}
	172
	173	static inline void destroy_context(struct mm_struct *mm)
	174	{
	175	struct sram_list_struct *tmp;
b8a98989 GY	176	#ifdef CONFIG_MPU
	177	unsigned int cpu = smp_processor_id();
	178	#endif
ca87b7ad GY	179
	180	#ifdef CONFIG_APP_STACK_L1
	181	if (current_l1_stack_save == mm->context.l1_stack_save)
	182	current_l1_stack_save = 0;
	183	if (mm->context.l1_stack_save)
	184	free_l1stack();
	185	#endif
	186
	187	while ((tmp = mm->context.sram_list)) {
	188	mm->context.sram_list = tmp->next;
	189	sram_free(tmp->addr);
	190	kfree(tmp);
	191	}
	192	#ifdef CONFIG_MPU
b8a98989 GY	193	if (current_rwx_mask[cpu] == mm->context.page_rwx_mask)
b8a98989 GY	194	current_rwx_mask[cpu] = NULL;
ca87b7ad GY	195	free_pages((unsigned long)mm->context.page_rwx_mask, page_mask_order);
	196	#endif
	197	}
	198
1394f032	199	#endif