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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
*/
#ifndef __UM_TLBFLUSH_H
#define __UM_TLBFLUSH_H
#include <linux/mm.h>
/*
* In UML, we need to sync the TLB over by using mmap/munmap/mprotect syscalls
* from the process handling the MM (which can be the kernel itself).
*
* To track updates, we can hook into set_ptes and flush_tlb_*. With set_ptes
* we catch all PTE transitions where memory that was unusable becomes usable.
* While with flush_tlb_* we can track any memory that becomes unusable and
* even if a higher layer of the page table was modified.
*
* So, we simply track updates using both methods and mark the memory area to
* be synced later on. The only special case is that flush_tlb_kern_* needs to
* be executed immediately as there is no good synchronization point in that
* case. In contrast, in the set_ptes case we can wait for the next kernel
* segfault before we do the synchornization.
*
* - flush_tlb_all() flushes all processes TLBs
* - flush_tlb_mm(mm) flushes the specified mm context TLB's
* - flush_tlb_page(vma, vmaddr) flushes one page
* - flush_tlb_range(vma, start, end) flushes a range of pages
* - flush_tlb_kernel_range(start, end) flushes a range of kernel pages
*/
extern int um_tlb_sync(struct mm_struct *mm);
extern void flush_tlb_all(void);
extern void flush_tlb_mm(struct mm_struct *mm);
static inline void flush_tlb_page(struct vm_area_struct *vma,
unsigned long address)
{
um_tlb_mark_sync(vma->vm_mm, address, address + PAGE_SIZE);
}
static inline void flush_tlb_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
um_tlb_mark_sync(vma->vm_mm, start, end);
}
static inline void flush_tlb_kernel_range(unsigned long start,
unsigned long end)
{
um_tlb_mark_sync(&init_mm, start, end);
/* Kernel needs to be synced immediately */
um_tlb_sync(&init_mm);
}
#endif
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