pgd_t *get_pgd_slow(void)
{
	/*
	 * need to get a 16k page for level 1
	 */
	pgd_t *pgd = (pgd_t *)__get_free_pages(GFP_KERNEL,2);
	pgd_t *init;

	if (pgd) {
		init = pgd_offset(&init_mm, 0);
		memzero(pgd, USER_PTRS_PER_PGD * BYTES_PER_PTR);
		memcpy(pgd + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
			(PTRS_PER_PGD - USER_PTRS_PER_PGD) * BYTES_PER_PTR);
		clean_cache_area(pgd, PTRS_PER_PGD * BYTES_PER_PTR);
	}
	return pgd;
}
pte_t *get_pte_kernel_slow(pmd_t *pmd, unsigned long offset)
{
	pte_t *pte;

	pte = (pte_t *)get_page_2k(GFP_KERNEL);
	if (pmd_none(*pmd)) {
		if (pte) {
			memzero(pte, 2 * PTRS_PER_PTE * BYTES_PER_PTR);
			clean_cache_area(pte, PTRS_PER_PTE * BYTES_PER_PTR);
			pte += PTRS_PER_PTE;
			set_pmd(pmd, mk_kernel_pmd(pte));
			return pte + offset;
		}
		set_pmd(pmd, mk_kernel_pmd(BAD_PAGETABLE));
		return NULL;
	}
	free_page_2k((unsigned long)pte);
	if (pmd_bad(*pmd)) {
		__bad_pmd_kernel(pmd);
		return NULL;
	}
	return (pte_t *) pmd_page(*pmd) + offset;
}
Exemple #3
0
/*
 * need to get a 16k page for level 1
 */
pgd_t *get_pgd_slow(struct mm_struct *mm)
{
	pgd_t *new_pgd, *init_pgd;
	pmd_t *new_pmd, *init_pmd;
	pte_t *new_pte, *init_pte;

	new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2);
	if (!new_pgd)
		goto no_pgd;

	memzero(new_pgd, FIRST_KERNEL_PGD_NR * sizeof(pgd_t));

	init_pgd = pgd_offset_k(0);

	if (vectors_base() == 0) {
		init_pmd = pmd_offset(init_pgd, 0);
		init_pte = pte_offset(init_pmd, 0);

		/*
		 * This lock is here just to satisfy pmd_alloc and pte_lock
		 */
		spin_lock(&mm->page_table_lock);

		/*
		 * On ARM, first page must always be allocated since it
		 * contains the machine vectors.
		 */
		new_pmd = pmd_alloc(mm, new_pgd, 0);
		if (!new_pmd)
			goto no_pmd;

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

		set_pte(new_pte, *init_pte);

		spin_unlock(&mm->page_table_lock);
	}

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

	/*
	 * FIXME: this should not be necessary
	 */
	clean_cache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));

	return new_pgd;

no_pte:
	spin_unlock(&mm->page_table_lock);
	pmd_free(new_pmd);
	free_pages((unsigned long)new_pgd, 2);
	return NULL;

no_pmd:
	spin_unlock(&mm->page_table_lock);
	free_pages((unsigned long)new_pgd, 2);
	return NULL;

no_pgd:
	return NULL;
}