kernel_samsung_msm8974/arch/arm/mm/pgd.c

/*
 *  linux/arch/arm/mm/pgd.c
 *
 *  Copyright (C) 1998-2005 Russell King
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/mm.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/slab.h>

#include <asm/cp15.h>
#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/tlbflush.h>

#include "mm.h"

#ifdef CONFIG_ARM_LPAE
#define __pgd_alloc()	kmalloc(PTRS_PER_PGD * sizeof(pgd_t), GFP_KERNEL)
#define __pgd_free(pgd)	kfree(pgd)
#else
#define __pgd_alloc()	(pgd_t *)__get_free_pages(GFP_KERNEL, 2)
#define __pgd_free(pgd)	free_pages((unsigned long)pgd, 2)
#endif

/*
 * need to get a 16k page for level 1
 */
pgd_t *pgd_alloc(struct mm_struct *mm)
{
	pgd_t *new_pgd, *init_pgd;
	pud_t *new_pud, *init_pud;
	pmd_t *new_pmd, *init_pmd;
	pte_t *new_pte, *init_pte;

	new_pgd = __pgd_alloc();
	if (!new_pgd)
		goto no_pgd;

	memset(new_pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));

	/*
	 * Copy over the kernel and IO PGD entries
	 */
	init_pgd = pgd_offset_k(0);
	memcpy(new_pgd + USER_PTRS_PER_PGD, init_pgd + USER_PTRS_PER_PGD,
		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));

	clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));

#ifdef CONFIG_ARM_LPAE
	/*
	 * Allocate PMD table for modules and pkmap mappings.
	 */
	new_pud = pud_alloc(mm, new_pgd + pgd_index(MODULES_VADDR),
			    MODULES_VADDR);
	if (!new_pud)
		goto no_pud;

	new_pmd = pmd_alloc(mm, new_pud, 0);
	if (!new_pmd)
		goto no_pmd;
#endif

	if (!vectors_high()) {
		/*
		 * On ARM, first page must always be allocated since it
		 * contains the machine vectors. The vectors are always high
		 * with LPAE.
		 */
		new_pud = pud_alloc(mm, new_pgd, 0);
		if (!new_pud)
			goto no_pud;

		new_pmd = pmd_alloc(mm, new_pud, 0);
		if (!new_pmd)
			goto no_pmd;

		new_pte = pte_alloc_map(mm, NULL, new_pmd, 0);
		if (!new_pte)
			goto no_pte;

		init_pud = pud_offset(init_pgd, 0);
		init_pmd = pmd_offset(init_pud, 0);
		init_pte = pte_offset_map(init_pmd, 0);
		set_pte_ext(new_pte, *init_pte, 0);
		pte_unmap(init_pte);
		pte_unmap(new_pte);
	}

	return new_pgd;

no_pte:
	pmd_free(mm, new_pmd);
no_pmd:
	pud_free(mm, new_pud);
no_pud:
	__pgd_free(new_pgd);
no_pgd:
	return NULL;
}

void pgd_free(struct mm_struct *mm, pgd_t *pgd_base)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pgtable_t pte;
#ifdef  CONFIG_TIMA_RKP_L1_TABLES
	unsigned long cmd_id = 0x3f80b221;
	unsigned long pmd_base;
#if __GNUC__ >= 4 && __GNUC_MINOR__ >= 6
        __asm__ __volatile__(".arch_extension sec\n");
#endif
#endif

	if (!pgd_base)
		return;

	pgd = pgd_base + pgd_index(0);
	if (pgd_none_or_clear_bad(pgd))
		goto no_pgd;

	pud = pud_offset(pgd, 0);
	if (pud_none_or_clear_bad(pud))
		goto no_pud;

	pmd = pmd_offset(pud, 0);
	if (pmd_none_or_clear_bad(pmd))
		goto no_pmd;

	pte = pmd_pgtable(*pmd);
	pmd_clear(pmd);
	pte_free(mm, pte);
no_pmd:
	pud_clear(pud);
	pmd_free(mm, pmd);
no_pud:
	pgd_clear(pgd);
	pud_free(mm, pud);
no_pgd:
#ifdef CONFIG_ARM_LPAE
	/*
	 * Free modules/pkmap or identity pmd tables.
	 */
	for (pgd = pgd_base; pgd < pgd_base + PTRS_PER_PGD; pgd++) {
		if (pgd_none_or_clear_bad(pgd))
			continue;
		if (pgd_val(*pgd) & L_PGD_SWAPPER)
			continue;
		pud = pud_offset(pgd, 0);
		if (pud_none_or_clear_bad(pud))
			continue;
		pmd = pmd_offset(pud, 0);
		pud_clear(pud);
		pmd_free(mm, pmd);
		pgd_clear(pgd);
		pud_free(mm, pud);
	}
#endif
#ifdef  CONFIG_TIMA_RKP_L1_TABLES
	if (tima_is_pg_protected((unsigned long) pgd) != 0) {
	__asm__ __volatile__ (
		"stmfd  sp!,{r0-r1, r11}\n"
		"mov   	r11, r0\n"
		"mov    r0, %0\n"
		"mov    r1, %1\n"
		"smc    #11\n"
		"mov    r0, #0\n"
		"mcr    p15, 0, r0, c8, c3, 0\n"
       		"dsb\n"
       		"isb\n"
		"pop    {r0-r1, r11}\n"
		::"r"(cmd_id),"r"(pgd):"r0","r1","r11","cc");

        pmd_base = ((unsigned long)pgd) & (~0x3fff);
	tima_verify_state(pmd_base, 0, 0, 3);
	tima_verify_state(pmd_base + 0x1000, 0, 0, 3);
	tima_verify_state(pmd_base + 0x2000, 0, 0, 3);
	tima_verify_state(pmd_base + 0x3000, 0, 0, 3);
	}
#endif
	__pgd_free(pgd_base);
}