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/* SPDX-License-Identifier: GPL-2.0-only *//* * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) * * vineetg: June 2011 *  -"/proc/meminfo | grep PageTables" kept on increasing *   Recently added pgtable dtor was not getting called. * * vineetg: May 2011 *  -Variable pg-sz means that Page Tables could be variable sized themselves *    So calculate it based on addr traversal split [pgd-bits:pte-bits:xxx] *  -Page Table size capped to max 1 to save memory - hence verified. *  -Since these deal with constants, gcc compile-time optimizes them. * * vineetg: Nov 2010 *  -Added pgtable ctor/dtor used for pgtable mem accounting * * vineetg: April 2010 *  -Switched pgtable_t from being struct page * to unsigned long *      =Needed so that Page Table allocator (pte_alloc_one) is not forced to *       to deal with struct page. Thay way in future we can make it allocate *       multiple PG Tbls in one Page Frame *      =sweet side effect is avoiding calls to ugly page_address( ) from the *       pg-tlb allocator sub-sys (pte_alloc_one, ptr_free, pmd_populate * *  Amit Bhor, Sameer Dhavale: Codito Technologies 2004 */ #ifndef _ASM_ARC_PGALLOC_H#define _ASM_ARC_PGALLOC_H #include <linux/mm.h>#include <linux/log2.h> static inline voidpmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte){	pmd_set(pmd, pte);} static inline voidpmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t ptep){	pmd_set(pmd, (pte_t *) ptep);} static inline int __get_order_pgd(void){	return get_order(PTRS_PER_PGD * sizeof(pgd_t));} static inline pgd_t *pgd_alloc(struct mm_struct *mm){	int num, num2;	pgd_t *ret = (pgd_t *) __get_free_pages(GFP_KERNEL, __get_order_pgd()); 	if (ret) {		num = USER_PTRS_PER_PGD + USER_KERNEL_GUTTER / PGDIR_SIZE;		memzero(ret, num * sizeof(pgd_t)); 		num2 = VMALLOC_SIZE / PGDIR_SIZE;		memcpy(ret + num, swapper_pg_dir + num, num2 * sizeof(pgd_t)); 		memzero(ret + num + num2,			       (PTRS_PER_PGD - num - num2) * sizeof(pgd_t)); 	}	return ret;} static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd){	free_pages((unsigned long)pgd, __get_order_pgd());}  /* * With software-only page-tables, addr-split for traversal is tweakable and * that directly governs how big tables would be at each level. * Further, the MMU page size is configurable. * Thus we need to programatically assert the size constraint * All of this is const math, allowing gcc to do constant folding/propagation. */ static inline int __get_order_pte(void){	return get_order(PTRS_PER_PTE * sizeof(pte_t));} static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm){	pte_t *pte; 	pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,					 __get_order_pte()); 	return pte;} static inline pgtable_tpte_alloc_one(struct mm_struct *mm){	pgtable_t pte_pg;	struct page *page; 	pte_pg = (pgtable_t)__get_free_pages(GFP_KERNEL, __get_order_pte());	if (!pte_pg)		return 0;	memzero((void *)pte_pg, PTRS_PER_PTE * sizeof(pte_t));	page = virt_to_page(pte_pg);	if (!pgtable_pte_page_ctor(page)) {		__free_page(page);		return 0;	} 	return pte_pg;} static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte){	free_pages((unsigned long)pte, __get_order_pte()); /* takes phy addr */} static inline void pte_free(struct mm_struct *mm, pgtable_t ptep){	pgtable_pte_page_dtor(virt_to_page(ptep));	free_pages((unsigned long)ptep, __get_order_pte());} #define __pte_free_tlb(tlb, pte, addr)  pte_free((tlb)->mm, pte) #define pmd_pgtable(pmd)	((pgtable_t) pmd_page_vaddr(pmd)) #endif /* _ASM_ARC_PGALLOC_H */