powerpc/mem: Use kmap_local_page() in flushing functions

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@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/b6a880ea0ec7886b51edbb4979c188be549231c0.1617895813.git.christophe.leroy@csgroup.eu

diff --git a/arch/powerpc/mm/cacheflush.c b/arch/powerpc/mm/cacheflush.c
index d9eafa077c094169a00c82486d5dbc2b1c5ceced..63363787e0007607ae4ee10ed9f0b39df2ec6fc7 100644 (file)
--- 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);
 }