linux/arch/arm64/include/asm/tlbflush.h
Catalin Marinas 285994a62c arm64: Invalidate the TLB corresponding to intermediate page table levels
The ARM architecture allows the caching of intermediate page table
levels and page table freeing requires a sequence like:

	pmd_clear()
	TLB invalidation
	pte page freeing

With commit 5e5f6dc105 (arm64: mm: enable HAVE_RCU_TABLE_FREE logic),
the page table freeing batching was moved from tlb_remove_page() to
tlb_remove_table(). The former takes care of TLB invalidation as this is
also shared with pte clearing and page cache page freeing. The latter,
however, does not invalidate the TLBs for intermediate page table levels
as it probably relies on the architecture code to do it if required.
When the mm->mm_users < 2, tlb_remove_table() does not do any batching
and page table pages are freed before tlb_finish_mmu() which performs
the actual TLB invalidation.

This patch introduces __tlb_flush_pgtable() for arm64 and calls it from
the {pte,pmd,pud}_free_tlb() directly without relying on deferred page
table freeing.

Fixes: 5e5f6dc105 arm64: mm: enable HAVE_RCU_TABLE_FREE logic
Reported-by: Jon Masters <jcm@redhat.com>
Tested-by: Jon Masters <jcm@redhat.com>
Tested-by: Steve Capper <steve.capper@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-03-14 10:48:30 +00:00

177 lines
4.5 KiB
C

/*
* Based on arch/arm/include/asm/tlbflush.h
*
* Copyright (C) 1999-2003 Russell King
* Copyright (C) 2012 ARM Ltd.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef __ASM_TLBFLUSH_H
#define __ASM_TLBFLUSH_H
#ifndef __ASSEMBLY__
#include <linux/sched.h>
#include <asm/cputype.h>
/*
* TLB Management
* ==============
*
* The arch/arm64/mm/tlb.S files implement these methods.
*
* The TLB specific code is expected to perform whatever tests it needs
* to determine if it should invalidate the TLB for each call. Start
* addresses are inclusive and end addresses are exclusive; it is safe to
* round these addresses down.
*
* flush_tlb_all()
*
* Invalidate the entire TLB.
*
* flush_tlb_mm(mm)
*
* Invalidate all TLB entries in a particular address space.
* - mm - mm_struct describing address space
*
* flush_tlb_range(mm,start,end)
*
* Invalidate a range of TLB entries in the specified address
* space.
* - mm - mm_struct describing address space
* - start - start address (may not be aligned)
* - end - end address (exclusive, may not be aligned)
*
* flush_tlb_page(vaddr,vma)
*
* Invalidate the specified page in the specified address range.
* - vaddr - virtual address (may not be aligned)
* - vma - vma_struct describing address range
*
* flush_kern_tlb_page(kaddr)
*
* Invalidate the TLB entry for the specified page. The address
* will be in the kernels virtual memory space. Current uses
* only require the D-TLB to be invalidated.
* - kaddr - Kernel virtual memory address
*/
static inline void flush_tlb_all(void)
{
dsb(ishst);
asm("tlbi vmalle1is");
dsb(ish);
isb();
}
static inline void flush_tlb_mm(struct mm_struct *mm)
{
unsigned long asid = (unsigned long)ASID(mm) << 48;
dsb(ishst);
asm("tlbi aside1is, %0" : : "r" (asid));
dsb(ish);
}
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long uaddr)
{
unsigned long addr = uaddr >> 12 |
((unsigned long)ASID(vma->vm_mm) << 48);
dsb(ishst);
asm("tlbi vae1is, %0" : : "r" (addr));
dsb(ish);
}
static inline void __flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
unsigned long asid = (unsigned long)ASID(vma->vm_mm) << 48;
unsigned long addr;
start = asid | (start >> 12);
end = asid | (end >> 12);
dsb(ishst);
for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
asm("tlbi vae1is, %0" : : "r"(addr));
dsb(ish);
}
static inline void __flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
unsigned long addr;
start >>= 12;
end >>= 12;
dsb(ishst);
for (addr = start; addr < end; addr += 1 << (PAGE_SHIFT - 12))
asm("tlbi vaae1is, %0" : : "r"(addr));
dsb(ish);
isb();
}
/*
* This is meant to avoid soft lock-ups on large TLB flushing ranges and not
* necessarily a performance improvement.
*/
#define MAX_TLB_RANGE (1024UL << PAGE_SHIFT)
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
if ((end - start) <= MAX_TLB_RANGE)
__flush_tlb_range(vma, start, end);
else
flush_tlb_mm(vma->vm_mm);
}
static inline void flush_tlb_kernel_range(unsigned long start, unsigned long end)
{
if ((end - start) <= MAX_TLB_RANGE)
__flush_tlb_kernel_range(start, end);
else
flush_tlb_all();
}
/*
* Used to invalidate the TLB (walk caches) corresponding to intermediate page
* table levels (pgd/pud/pmd).
*/
static inline void __flush_tlb_pgtable(struct mm_struct *mm,
unsigned long uaddr)
{
unsigned long addr = uaddr >> 12 | ((unsigned long)ASID(mm) << 48);
dsb(ishst);
asm("tlbi vae1is, %0" : : "r" (addr));
dsb(ish);
}
/*
* On AArch64, the cache coherency is handled via the set_pte_at() function.
*/
static inline void update_mmu_cache(struct vm_area_struct *vma,
unsigned long addr, pte_t *ptep)
{
/*
* set_pte() does not have a DSB for user mappings, so make sure that
* the page table write is visible.
*/
dsb(ishst);
}
#define update_mmu_cache_pmd(vma, address, pmd) do { } while (0)
#endif
#endif