[PATCH v2 9/9] powerpc/mem: Use kmap_local_page() in flushing functions

From: Christophe Leroy
Date: Thu Apr 08 2021 - 11:31:17 EST


Flushing functions don't rely on preemption being disabled, so
use kmap_local_page() instead of kmap_atomic().

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/mm/cacheflush.c | 19 ++++++++++---------
1 file changed, 10 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/mm/cacheflush.c b/arch/powerpc/mm/cacheflush.c
index d9eafa077c09..63363787e000 100644
--- a/arch/powerpc/mm/cacheflush.c
+++ b/arch/powerpc/mm/cacheflush.c
@@ -152,16 +152,16 @@ static void flush_dcache_icache_hugepage(struct page *page)
{
int i;
int nr = compound_nr(page);
- void *start;

if (!PageHighMem(page)) {
for (i = 0; i < nr; i++)
__flush_dcache_icache(lowmem_page_address(page + i));
} else {
for (i = 0; i < nr; i++) {
- start = kmap_atomic(page+i);
+ void *start = kmap_local_page(page + i);
+
__flush_dcache_icache(start);
- kunmap_atomic(start);
+ kunmap_local(start);
}
}
}
@@ -177,9 +177,10 @@ void flush_dcache_icache_page(struct page *page)
if (!PageHighMem(page)) {
__flush_dcache_icache(lowmem_page_address(page));
} else if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) {
- void *start = kmap_atomic(page);
+ void *start = kmap_local_page(page);
+
__flush_dcache_icache(start);
- kunmap_atomic(start);
+ kunmap_local(start);
} else {
flush_dcache_icache_phys(page_to_phys(page));
}
@@ -225,9 +226,9 @@ void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
void flush_icache_user_page(struct vm_area_struct *vma, struct page *page,
unsigned long addr, int len)
{
- unsigned long maddr;
+ void *maddr;

- maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
- flush_icache_range(maddr, maddr + len);
- kunmap(page);
+ maddr = kmap_local_page(page) + (addr & ~PAGE_MASK);
+ flush_icache_range((unsigned long)maddr, (unsigned long)maddr + len);
+ kunmap_local(maddr);
}
--
2.25.0