xtensa: support aliasing cache in kmap

Define ARCH_PKMAP_COLORING and provide corresponding macro definitions
on cores with aliasing data cache.

Instead of single last_pkmap_nr maintain an array last_pkmap_nr_arr of
pkmap counters for each page color. Make sure that kmap maps physical
page at virtual address with color matching its physical address.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>

1 files changed, 18 insertions, 0 deletions

diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
index 466abaed5382..8cfb71ec0937 100644
--- a/arch/xtensa/mm/highmem.c
+++ b/arch/xtensa/mm/highmem.c
@@ -14,6 +14,23 @@
 
 static pte_t *kmap_pte;
 
+#if DCACHE_WAY_SIZE > PAGE_SIZE
+unsigned int last_pkmap_nr_arr[DCACHE_N_COLORS];
+wait_queue_head_t pkmap_map_wait_arr[DCACHE_N_COLORS];
+
+static void __init kmap_waitqueues_init(void)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(pkmap_map_wait_arr); ++i)
+		init_waitqueue_head(pkmap_map_wait_arr + i);
+}
+#else
+static inline void kmap_waitqueues_init(void)
+{
+}
+#endif
+
 static inline enum fixed_addresses kmap_idx(int type, unsigned long color)
 {
 	return (type + KM_TYPE_NR * smp_processor_id()) * DCACHE_N_COLORS +
@@ -72,4 +89,5 @@ void __init kmap_init(void)
 	/* cache the first kmap pte */
 	kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
 	kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+	kmap_waitqueues_init();
 }