linuxdebug/arch/arc/include/asm/pgalloc.h

98 lines
2.8 KiB
C
Raw Normal View History

2024-07-16 15:50:57 +02:00
/* 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
* deal with struct page. That 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>
#include <asm-generic/pgalloc.h>
static inline void
pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd, pte_t *pte)
{
/*
* The cast to long below is OK in 32-bit PAE40 regime with long long pte
* Despite "wider" pte, the pte table needs to be in non-PAE low memory
* as all higher levels can only hold long pointers.
*
* The cast itself is needed given simplistic definition of set_pmd()
*/
set_pmd(pmd, __pmd((unsigned long)pte));
}
static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd, pgtable_t pte_page)
{
set_pmd(pmd, __pmd((unsigned long)page_address(pte_page)));
}
static inline pgd_t *pgd_alloc(struct mm_struct *mm)
{
pgd_t *ret = (pgd_t *) __get_free_page(GFP_KERNEL);
if (ret) {
int num, num2;
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;
}
#if CONFIG_PGTABLE_LEVELS > 3
static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4dp, pud_t *pudp)
{
set_p4d(p4dp, __p4d((unsigned long)pudp));
}
#define __pud_free_tlb(tlb, pmd, addr) pud_free((tlb)->mm, pmd)
#endif
#if CONFIG_PGTABLE_LEVELS > 2
static inline void pud_populate(struct mm_struct *mm, pud_t *pudp, pmd_t *pmdp)
{
set_pud(pudp, __pud((unsigned long)pmdp));
}
#define __pmd_free_tlb(tlb, pmd, addr) pmd_free((tlb)->mm, pmd)
#endif
#define __pte_free_tlb(tlb, pte, addr) pte_free((tlb)->mm, pte)
#endif /* _ASM_ARC_PGALLOC_H */