csky/mm/highmem: Switch to generic kmap atomic

No reason having the same code in every architecture.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Guo Ren <guoren@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20201103095857.681196473@linutronix.de

arch/csky/Kconfig

@@ -286,6 +286,7 @@ config NR_CPUS
 config HIGHMEM
 	bool "High Memory Support"
 	depends on !CPU_CK610
+	select KMAP_LOCAL
 	default y
 
 config FORCE_MAX_ZONEORDER

arch/csky/include/asm/fixmap.h

@@ -8,7 +8,7 @@
 #include <asm/memory.h>
 #ifdef CONFIG_HIGHMEM
 #include <linux/threads.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #endif
 
 enum fixed_addresses {
@@ -17,7 +17,7 @@ enum fixed_addresses {
 #endif
 #ifdef CONFIG_HIGHMEM
 	FIX_KMAP_BEGIN,
-	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1,
 #endif
 	__end_of_fixed_addresses
 };

arch/csky/include/asm/highmem.h

@@ -9,7 +9,7 @@
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/uaccess.h>
-#include <asm/kmap_types.h>
+#include <asm/kmap_size.h>
 #include <asm/cache.h>
 
 /* undef for production */
@@ -32,10 +32,12 @@ extern pte_t *pkmap_page_table;
 
 #define ARCH_HAS_KMAP_FLUSH_TLB
 extern void kmap_flush_tlb(unsigned long addr);
-extern void *kmap_atomic_pfn(unsigned long pfn);
 
 #define flush_cache_kmaps() do {} while (0)
 
+#define arch_kmap_local_post_map(vaddr, pteval)	kmap_flush_tlb(vaddr)
+#define arch_kmap_local_post_unmap(vaddr)	kmap_flush_tlb(vaddr)
+
 extern void kmap_init(void);
 
 #endif /* __KERNEL__ */

arch/csky/mm/highmem.c

@@ -9,8 +9,6 @@
 #include <asm/tlbflush.h>
 #include <asm/cacheflush.h>
 
-static pte_t *kmap_pte;
-
 unsigned long highstart_pfn, highend_pfn;
 
 void kmap_flush_tlb(unsigned long addr)
@@ -19,67 +17,7 @@ void kmap_flush_tlb(unsigned long addr)
 }
 EXPORT_SYMBOL(kmap_flush_tlb);
 
-void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-#ifdef CONFIG_DEBUG_HIGHMEM
-	BUG_ON(!pte_none(*(kmap_pte - idx)));
-#endif
-	set_pte(kmap_pte-idx, mk_pte(page, prot));
-	flush_tlb_one((unsigned long)vaddr);
-
-	return (void *)vaddr;
-}
-EXPORT_SYMBOL(kmap_atomic_high_prot);
-
-void kunmap_atomic_high(void *kvaddr)
-{
-	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
-	int idx;
-
-	if (vaddr < FIXADDR_START)
-		return;
-
-#ifdef CONFIG_DEBUG_HIGHMEM
-	idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
-
-	BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
-
-	pte_clear(&init_mm, vaddr, kmap_pte - idx);
-	flush_tlb_one(vaddr);
-#else
-	(void) idx; /* to kill a warning */
-#endif
-	kmap_atomic_idx_pop();
-}
-EXPORT_SYMBOL(kunmap_atomic_high);
-
-/*
- * This is the same as kmap_atomic() but can map memory that doesn't
- * have a struct page associated with it.
- */
-void *kmap_atomic_pfn(unsigned long pfn)
-{
-	unsigned long vaddr;
-	int idx, type;
-
-	pagefault_disable();
-
-	type = kmap_atomic_idx_push();
-	idx = type + KM_TYPE_NR*smp_processor_id();
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
-	set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
-	flush_tlb_one(vaddr);
-
-	return (void *) vaddr;
-}
-
-static void __init kmap_pages_init(void)
+void __init kmap_init(void)
 {
 	unsigned long vaddr;
 	pgd_t *pgd;
@@ -96,14 +34,3 @@ static void __init kmap_pages_init(void)
 	pte = pte_offset_kernel(pmd, vaddr);
 	pkmap_page_table = pte;
 }
-
-void __init kmap_init(void)
-{
-	unsigned long vaddr;
-
-	kmap_pages_init();
-
-	vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
-
-	kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
-}