tmp_suning_uos_patched/arch/arm64/mm/flush.c
Ben Hutchings c5157101e7 arm64: mm: Export __sync_icache_dcache() for xen-privcmd
The xen-privcmd driver, which can be modular, calls set_pte_at()
which in turn may call __sync_icache_dcache().

The call to __sync_icache_dcache() may be optimised out because it is
conditional on !pte_special(), and xen-privcmd calls pte_mkspecial().
But it seems unwise to rely on this optimisation.

Fixes: 3ad0876554 ("xen/privcmd: add IOCTL_PRIVCMD_MMAP_RESOURCE")
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-07-27 13:12:15 +01:00

103 lines
2.7 KiB
C

/*
* Based on arch/arm/mm/flush.c
*
* Copyright (C) 1995-2002 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/>.
*/
#include <linux/export.h>
#include <linux/mm.h>
#include <linux/pagemap.h>
#include <asm/cacheflush.h>
#include <asm/cache.h>
#include <asm/tlbflush.h>
void sync_icache_aliases(void *kaddr, unsigned long len)
{
unsigned long addr = (unsigned long)kaddr;
if (icache_is_aliasing()) {
__clean_dcache_area_pou(kaddr, len);
__flush_icache_all();
} else {
flush_icache_range(addr, addr + len);
}
}
static void flush_ptrace_access(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *kaddr,
unsigned long len)
{
if (vma->vm_flags & VM_EXEC)
sync_icache_aliases(kaddr, len);
}
/*
* 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.
*/
void copy_to_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long uaddr, void *dst, const void *src,
unsigned long len)
{
memcpy(dst, src, len);
flush_ptrace_access(vma, page, uaddr, dst, len);
}
void __sync_icache_dcache(pte_t pte)
{
struct page *page = pte_page(pte);
if (!test_and_set_bit(PG_dcache_clean, &page->flags))
sync_icache_aliases(page_address(page),
PAGE_SIZE << compound_order(page));
}
EXPORT_SYMBOL_GPL(__sync_icache_dcache);
/*
* This function is called when a page has been modified by the kernel. Mark
* it as dirty for later flushing when mapped in user space (if executable,
* see __sync_icache_dcache).
*/
void flush_dcache_page(struct page *page)
{
if (test_bit(PG_dcache_clean, &page->flags))
clear_bit(PG_dcache_clean, &page->flags);
}
EXPORT_SYMBOL(flush_dcache_page);
/*
* Additional functions defined in assembly.
*/
EXPORT_SYMBOL(__flush_icache_range);
#ifdef CONFIG_ARCH_HAS_PMEM_API
void arch_wb_cache_pmem(void *addr, size_t size)
{
/* Ensure order against any prior non-cacheable writes */
dmb(osh);
__clean_dcache_area_pop(addr, size);
}
EXPORT_SYMBOL_GPL(arch_wb_cache_pmem);
void arch_invalidate_pmem(void *addr, size_t size)
{
__inval_dcache_area(addr, size);
}
EXPORT_SYMBOL_GPL(arch_invalidate_pmem);
#endif