/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Based on arch/arm/include/asm/cacheflush.h
*
* Copyright (C) 1999-2002 Russell King.
* Copyright (C) 2012 ARM Ltd.
*/
#ifndef __ASM_CACHEFLUSH_H
#define __ASM_CACHEFLUSH_H
#include <linux/kgdb.h>
#include <linux/mm.h>
/*
* This flag is used to indicate that the page pointed to by a pte is clean
* and does not require cleaning before returning it to the user.
*/
#define PG_dcache_clean PG_arch_1
/*
* MM Cache Management
* ===================
*
* The arch/arm64/mm/cache.S implements these methods.
*
* Start addresses are inclusive and end addresses are exclusive; start
* addresses should be rounded down, end addresses up.
*
* See Documentation/core-api/cachetlb.rst for more information. Please note that
* the implementation assumes non-aliasing VIPT D-cache and (aliasing)
* VIPT I-cache.
*
* flush_cache_mm(mm)
*
* Clean and invalidate all user space cache entries
* before a change of page tables.
*
* flush_icache_range(start, end)
*
* Ensure coherency between the I-cache and the D-cache in the
* region described by start, end.
* - start - virtual start address
* - end - virtual end address
*
* invalidate_icache_range(start, end)
*
* Invalidate the I-cache in the region described by start, end.
* - start - virtual start address
* - end - virtual end address
*
* __flush_cache_user_range(start, end)
*
* Ensure coherency between the I-cache and the D-cache in the
* region described by start, end.
* - start - virtual start address
* - end - virtual end address
*
* __flush_dcache_area(kaddr, size)
*
* Ensure that the data held in page is written back.
* - kaddr - page address
* - size - region size
*/
extern void __flush_icache_range(unsigned long start, unsigned long end);
extern int invalidate_icache_range(unsigned long start, unsigned long end);
extern void __flush_dcache_area(void *addr, size_t len);
extern void __inval_dcache_area(void *addr, size_t len);
extern void __clean_dcache_area_poc(void *addr, size_t len);
extern void __clean_dcache_area_pop(void *addr, size_t len);
extern void __clean_dcache_area_pou(void *addr, size_t len);
extern long __flush_cache_user_range(unsigned long start, unsigned long end);
extern void sync_icache_aliases(void *kaddr, unsigned long len);
static inline void flush_icache_range(unsigned long start, unsigned long end)
{
__flush_icache_range(start, end);
/*
* IPI all online CPUs so that they undergo a context synchronization
* event and are forced to refetch the new instructions.
*/
#ifdef CONFIG_KGDB
/*
* KGDB performs cache maintenance with interrupts disabled, so we
* will deadlock trying to IPI the secondary CPUs. In theory, we can
* set CACHE_FLUSH_IS_SAFE to 0 to avoid this known issue, but that
* just means that KGDB will elide the maintenance altogether! As it
* turns out, KGDB uses IPIs to round-up the secondary CPUs during
* the patching operation, so we don't need extra IPIs here anyway.
* In which case, add a KGDB-specific bodge and return early.
*/
if (kgdb_connected && irqs_disabled())
return;
#endif
kick_all_cpus_sync();
}
static inline void flush_cache_mm(struct mm_struct *mm)
{
}
static inline void flush_cache_page(struct vm_area_struct *vma,
unsigned long user_addr, unsigned long pfn)
{
}
static inline void flush_cache_range(struct vm_area_struct *vma,
unsigned long start, unsigned long end)
{
}
/*
* Cache maintenance functions used by the DMA API. No to be used directly.
*/
extern void __dma_map_area(const void *, size_t, int);
extern void __dma_unmap_area(const void *, size_t, int);
extern void __dma_flush_area(const void *, size_t);
/*
* Copy user data from/to a page which is mapped into a different
* processes address space. Really, we want to allow our "user
* space" model to handle this.
*/
extern void copy_to_user_page(struct vm_area_struct *, struct page *,
unsigned long, void *, const void *, unsigned long);
#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
do { \
memcpy(dst, src, len); \
} while (0)
#define flush_cache_dup_mm(mm) flush_cache_mm(mm)
/*
* flush_dcache_page is used when the kernel has written to the page
* cache page at virtual address page->virtual.
*
* If this page isn't mapped (ie, page_mapping == NULL), or it might
* have userspace mappings, then we _must_ always clean + invalidate
* the dcache entries associated with the kernel mapping.
*
* Otherwise we can defer the operation, and clean the cache when we are
* about to change to user space. This is the same method as used on SPARC64.
* See update_mmu_cache for the user space part.
*/
#define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 1
extern void flush_dcache_page(struct page *);
static inline void __flush_icache_all(void)
{
if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC))
return;
asm("ic ialluis");
dsb(ish);
}
#define flush_dcache_mmap_lock(mapping) do { } while (0)
#define flush_dcache_mmap_unlock(mapping) do { } while (0)
/*
* We don't appear to need to do anything here. In fact, if we did, we'd
* duplicate cache flushing elsewhere performed by flush_dcache_page().
*/
#define flush_icache_page(vma,page) do { } while (0)
/*
* Not required on AArch64 (PIPT or VIPT non-aliasing D-cache).
*/
static inline void flush_cache_vmap(unsigned long start, unsigned long end)
{
}
static inline void flush_cache_vunmap(unsigned long start, unsigned long end)
{
}
int set_memory_valid(unsigned long addr, int numpages, int enable);
#endif
