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, 38 insertions, 2 deletions

diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 2653ef5d55f1..2c7901edffaf 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -12,19 +12,55 @@
 #ifndef _XTENSA_HIGHMEM_H
 #define _XTENSA_HIGHMEM_H
 
+#include <linux/wait.h>
 #include <asm/cacheflush.h>
 #include <asm/fixmap.h>
 #include <asm/kmap_types.h>
 #include <asm/pgtable.h>
 
-#define PKMAP_BASE              (FIXADDR_START - PMD_SIZE)
-#define LAST_PKMAP              PTRS_PER_PTE
+#define PKMAP_BASE              ((FIXADDR_START - \
+                                  (LAST_PKMAP + 1) * PAGE_SIZE) & PMD_MASK)
+#define LAST_PKMAP              (PTRS_PER_PTE * DCACHE_N_COLORS)
 #define LAST_PKMAP_MASK         (LAST_PKMAP - 1)
 #define PKMAP_NR(virt)          (((virt) - PKMAP_BASE) >> PAGE_SHIFT)
 #define PKMAP_ADDR(nr)          (PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
 #define kmap_prot               PAGE_KERNEL
 
+#if DCACHE_WAY_SIZE > PAGE_SIZE
+#define get_pkmap_color get_pkmap_color
+static inline int get_pkmap_color(struct page *page)
+{
+        return DCACHE_ALIAS(page_to_phys(page));
+}
+
+extern unsigned int last_pkmap_nr_arr[];
+
+static inline unsigned int get_next_pkmap_nr(unsigned int color)
+{
+        last_pkmap_nr_arr[color] =
+                (last_pkmap_nr_arr[color] + DCACHE_N_COLORS) & LAST_PKMAP_MASK;
+        return last_pkmap_nr_arr[color] + color;
+}
+
+static inline int no_more_pkmaps(unsigned int pkmap_nr, unsigned int color)
+{
+        return pkmap_nr < DCACHE_N_COLORS;
+}
+
+static inline int get_pkmap_entries_count(unsigned int color)
+{
+        return LAST_PKMAP / DCACHE_N_COLORS;
+}
+
+extern wait_queue_head_t pkmap_map_wait_arr[];
+
+static inline wait_queue_head_t *get_pkmap_wait_queue_head(unsigned int color)
+{
+        return pkmap_map_wait_arr + color;
+}
+#endif
+
 extern pte_t *pkmap_page_table;
 
 void *kmap_high(struct page *page);