kmap: consolidate kmap_prot definitions

Most architectures define kmap_prot to be PAGE_KERNEL.

Let sparc and xtensa define there own and define PAGE_KERNEL as the
default if not overridden.

[akpm@linux-foundation.org: coding style fixes]
Suggested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christian König <christian.koenig@amd.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200507150004.1423069-16-ira.weiny@intel.comSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/arc/include/asm/highmem.h

@@ -25,9 +25,6 @@
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
 #define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
 
-#define kmap_prot		PAGE_KERNEL
-
-
 #include <asm/cacheflush.h>
 
 extern void kmap_init(void);

arch/arm/include/asm/highmem.h

@@ -10,8 +10,6 @@
 #define PKMAP_NR(virt)		(((virt) - PKMAP_BASE) >> PAGE_SHIFT)
 #define PKMAP_ADDR(nr)		(PKMAP_BASE + ((nr) << PAGE_SHIFT))
 
-#define kmap_prot		PAGE_KERNEL
-
 #define flush_cache_kmaps() \
 	do { \
 		if (cache_is_vivt()) \

arch/csky/include/asm/highmem.h

@@ -38,8 +38,6 @@ extern void *kmap_atomic_pfn(unsigned long pfn);
 
 extern void kmap_init(void);
 
-#define kmap_prot PAGE_KERNEL
-
 #endif /* __KERNEL__ */
 
 #endif /* __ASM_CSKY_HIGHMEM_H */

arch/microblaze/include/asm/highmem.h

@@ -25,7 +25,6 @@
 #include <linux/uaccess.h>
 #include <asm/fixmap.h>
 
-#define kmap_prot		PAGE_KERNEL
 extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 

arch/mips/include/asm/highmem.h

@@ -54,8 +54,6 @@ extern void *kmap_atomic_pfn(unsigned long pfn);
 
 extern void kmap_init(void);
 
-#define kmap_prot PAGE_KERNEL
-
 #endif /* __KERNEL__ */
 
 #endif /* _ASM_HIGHMEM_H */

arch/nds32/include/asm/highmem.h

@@ -32,7 +32,6 @@
 #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
 
 static inline void flush_cache_kmaps(void)
 {

arch/powerpc/include/asm/highmem.h

@@ -29,7 +29,6 @@
 #include <asm/page.h>
 #include <asm/fixmap.h>
 
-#define kmap_prot		PAGE_KERNEL
 extern pte_t *kmap_pte;
 extern pte_t *pkmap_page_table;
 

arch/sparc/include/asm/highmem.h

@@ -25,11 +25,12 @@
 #include <asm/vaddrs.h>
 #include <asm/kmap_types.h>
 #include <asm/pgtable.h>
+#include <asm/pgtsrmmu.h>
 
 /* declarations for highmem.c */
 extern unsigned long highstart_pfn, highend_pfn;
 
-extern pgprot_t kmap_prot;
+#define kmap_prot __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE)
 extern pte_t *pkmap_page_table;
 
 void kmap_init(void) __init;

arch/sparc/mm/highmem.c

@@ -32,9 +32,6 @@
 #include <asm/pgalloc.h>
 #include <asm/vaddrs.h>
 
-pgprot_t kmap_prot;
-EXPORT_SYMBOL(kmap_prot);
-
 static pte_t *kmap_pte;
 
 void __init kmap_init(void)
@@ -51,7 +48,6 @@ void __init kmap_init(void)
 
         /* cache the first kmap pte */
         kmap_pte = pte_offset_kernel(dir, address);
-        kmap_prot = __pgprot(SRMMU_ET_PTE | SRMMU_PRIV | SRMMU_CACHE);
 }
 
 void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)

arch/x86/include/asm/fixmap.h

@@ -152,7 +152,6 @@ extern void reserve_top_address(unsigned long reserve);
 extern int fixmaps_set;
 
 extern pte_t *kmap_pte;
-#define kmap_prot PAGE_KERNEL
 extern pte_t *pkmap_page_table;
 
 void __native_set_fixmap(enum fixed_addresses idx, pte_t pte);

include/linux/highmem.h

@@ -40,6 +40,10 @@ extern void kunmap_atomic_high(void *kvaddr);
 static inline void kmap_flush_tlb(unsigned long addr) { }
 #endif
 
+#ifndef kmap_prot
+#define kmap_prot PAGE_KERNEL
+#endif
+
 void *kmap_high(struct page *page);
 static inline void *kmap(struct page *page)
 {