// SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2020-2022 Loongson Technology Corporation Limited */ #include <linux/init.h> #include <linux/export.h> #include <linux/mm.h> #include <asm/pgalloc.h> #include <asm/pgtable.h> #include <asm/tlbflush.h> pgd_t *pgd_alloc(struct mm_struct *mm) { pgd_t *ret, *init; ret = (pgd_t *) __get_free_page(GFP_KERNEL); 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; } EXPORT_SYMBOL_GPL(pgd_alloc); void pgd_init(void *addr) { unsigned long *p, *end; unsigned long entry; #if !defined(__PAGETABLE_PUD_FOLDED) entry = (unsigned long)invalid_pud_table; #elif !defined(__PAGETABLE_PMD_FOLDED) entry = (unsigned long)invalid_pmd_table; #else entry = (unsigned long)invalid_pte_table; #endif p = (unsigned long *)addr; end = p + PTRS_PER_PGD; do { p[0] = entry; p[1] = entry; p[2] = entry; p[3] = entry; p[4] = entry; p += 8; p[-3] = entry; p[-2] = entry; p[-1] = entry; } while (p != end); } EXPORT_SYMBOL_GPL(pgd_init); #ifndef __PAGETABLE_PMD_FOLDED void pmd_init(void *addr) { unsigned long *p, *end; unsigned long pagetable = (unsigned long)invalid_pte_table; p = (unsigned long *)addr; end = p + PTRS_PER_PMD; do { p[0] = pagetable; p[1] = pagetable; p[2] = pagetable; p[3] = pagetable; p[4] = pagetable; p += 8; p[-3] = pagetable; p[-2] = pagetable; p[-1] = pagetable; } while (p != end); } EXPORT_SYMBOL_GPL(pmd_init); #endif #ifndef __PAGETABLE_PUD_FOLDED void pud_init(void *addr) { unsigned long *p, *end; unsigned long pagetable = (unsigned long)invalid_pmd_table; p = (unsigned long *)addr; end = p + PTRS_PER_PUD; do { p[0] = pagetable; p[1] = pagetable; p[2] = pagetable; p[3] = pagetable; p[4] = pagetable; p += 8; p[-3] = pagetable; p[-2] = pagetable; p[-1] = pagetable; } while (p != end); } EXPORT_SYMBOL_GPL(pud_init); #endif pmd_t mk_pmd(struct page *page, pgprot_t prot) { pmd_t pmd; pmd_val(pmd) = (page_to_pfn(page) << _PFN_SHIFT) | pgprot_val(prot); return pmd; } void set_pmd_at(struct mm_struct *mm, unsigned long addr, pmd_t *pmdp, pmd_t pmd) { *pmdp = pmd; flush_tlb_all(); } void __init pagetable_init(void) { /* Initialize the entire pgd. */ pgd_init(swapper_pg_dir); pgd_init(invalid_pg_dir); #ifndef __PAGETABLE_PUD_FOLDED pud_init(invalid_pud_table); #endif #ifndef __PAGETABLE_PMD_FOLDED pmd_init(invalid_pmd_table); #endif }