/* * Copyright (C) 2009 Wind River Systems Inc * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com * * This file is subject to the terms and conditions of the GNU General Public * License. See the file "COPYING" in the main directory of this archive * for more details. */ #include <linux/mm.h> #include <linux/sched.h> #include <asm/cpuinfo.h> #include <asm/pgalloc.h> /* pteaddr: * ptbase | vpn* | zero * 31-22 | 21-2 | 1-0 * * *vpn is preserved on double fault * * tlbacc: * IG |*flags| pfn * 31-25|24-20 | 19-0 * * *crwxg * * tlbmisc: * resv |way |rd | we|pid |dbl|bad|perm|d * 31-24 |23-20 |19 | 20|17-4|3 |2 |1 |0 * */ /* * Initialize a new pgd / pmd table with invalid pointers. */ static void pgd_init(pgd_t *pgd) { unsigned long *p = (unsigned long *) pgd; int i; for (i = 0; i < USER_PTRS_PER_PGD; i += 8) { p[i + 0] = (unsigned long) invalid_pte_table; p[i + 1] = (unsigned long) invalid_pte_table; p[i + 2] = (unsigned long) invalid_pte_table; p[i + 3] = (unsigned long) invalid_pte_table; p[i + 4] = (unsigned long) invalid_pte_table; p[i + 5] = (unsigned long) invalid_pte_table; p[i + 6] = (unsigned long) invalid_pte_table; p[i + 7] = (unsigned long) invalid_pte_table; } } pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *ret, *init; ret = __pgd_alloc(mm, 0); if (ret) { init = pgd_offset(&init_mm, 0UL); pgd_init(ret); memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD, (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t)); } return ret; } void __init pagetable_init(void) { /* Initialize the entire pgd. */ pgd_init(swapper_pg_dir); pgd_init(swapper_pg_dir + USER_PTRS_PER_PGD); }