linux-brain/arch/arm64/mm/pgd.c
Mike Rapoport 782de70c42 mm: consolidate pgtable_cache_init() and pgd_cache_init()
Both pgtable_cache_init() and pgd_cache_init() are used to initialize kmem
cache for page table allocations on several architectures that do not use
PAGE_SIZE tables for one or more levels of the page table hierarchy.

Most architectures do not implement these functions and use __weak default
NOP implementation of pgd_cache_init().  Since there is no such default
for pgtable_cache_init(), its empty stub is duplicated among most
architectures.

Rename the definitions of pgd_cache_init() to pgtable_cache_init() and
drop empty stubs of pgtable_cache_init().

Link: http://lkml.kernel.org/r/1566457046-22637-1-git-send-email-rppt@linux.ibm.com
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Will Deacon <will@kernel.org>		[arm64]
Acked-by: Thomas Gleixner <tglx@linutronix.de>	[x86]
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-09-24 15:54:09 -07:00

57 lines
1.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* PGD allocation/freeing
*
* Copyright (C) 2012 ARM Ltd.
* Author: Catalin Marinas <catalin.marinas@arm.com>
*/
#include <linux/mm.h>
#include <linux/gfp.h>
#include <linux/highmem.h>
#include <linux/slab.h>
#include <asm/pgalloc.h>
#include <asm/page.h>
#include <asm/tlbflush.h>
static struct kmem_cache *pgd_cache __ro_after_init;
pgd_t *pgd_alloc(struct mm_struct *mm)
{
gfp_t gfp = GFP_PGTABLE_USER;
if (PGD_SIZE == PAGE_SIZE)
return (pgd_t *)__get_free_page(gfp);
else
return kmem_cache_alloc(pgd_cache, gfp);
}
void pgd_free(struct mm_struct *mm, pgd_t *pgd)
{
if (PGD_SIZE == PAGE_SIZE)
free_page((unsigned long)pgd);
else
kmem_cache_free(pgd_cache, pgd);
}
void __init pgtable_cache_init(void)
{
if (PGD_SIZE == PAGE_SIZE)
return;
#ifdef CONFIG_ARM64_PA_BITS_52
/*
* With 52-bit physical addresses, the architecture requires the
* top-level table to be aligned to at least 64 bytes.
*/
BUILD_BUG_ON(PGD_SIZE < 64);
#endif
/*
* Naturally aligned pgds required by the architecture.
*/
pgd_cache = kmem_cache_create("pgd_cache", PGD_SIZE, PGD_SIZE,
SLAB_PANIC, NULL);
}