arch/kunmap_atomic: consolidate duplicate code

Every single architecture (including !CONFIG_HIGHMEM) calls...

	pagefault_enable();
	preempt_enable();

... before returning from __kunmap_atomic().  Lift this code into the
kunmap_atomic() macro.

While we are at it rename __kunmap_atomic() to kunmap_atomic_high() to
be consistent.

[ira.weiny@intel.com: don't enable pagefault/preempt twice]
  Link: http://lkml.kernel.org/r/20200518184843.3029640-1-ira.weiny@intel.com
[akpm@linux-foundation.org: coding style fixes]
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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>
Cc: Guenter Roeck <linux@roeck-us.net>
Link: http://lkml.kernel.org/r/20200507150004.1423069-8-ira.weiny@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 3 insertions, 9 deletions

diff --git a/arch/powerpc/include/asm/highmem.h b/arch/powerpc/include/asm/highmem.h
index 74fa2c726fde..373a470df205 100644
--- a/arch/powerpc/include/asm/highmem.h
+++ b/arch/powerpc/include/asm/highmem.h
@@ -69,7 +69,6 @@ static inline void *kmap_atomic_prot(struct page *page, pgprot_t prot)
 
 	return kmap_atomic_high_prot(page, prot);
 }
-extern void __kunmap_atomic(void *kvaddr);
 
 static inline void *kmap_atomic_high(struct page *page)
 {
diff --git a/arch/powerpc/mm/highmem.c b/arch/powerpc/mm/highmem.c
index 67aaa5217f7f..624b4438aff9 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -40,15 +40,12 @@ void *kmap_atomic_high_prot(struct page *page, pgprot_t prot)
 }
 EXPORT_SYMBOL(kmap_atomic_high_prot);
 
-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
 {
 	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
 
-	if (vaddr < __fix_to_virt(FIX_KMAP_END)) {
-		pagefault_enable();
-		preempt_enable();
+	if (vaddr < __fix_to_virt(FIX_KMAP_END))
 		return;
-	}
 
 	if (IS_ENABLED(CONFIG_DEBUG_HIGHMEM)) {
 		int type = kmap_atomic_idx();
@@ -66,7 +63,5 @@ void __kunmap_atomic(void *kvaddr)
 	}
 
 	kmap_atomic_idx_pop();
-	pagefault_enable();
-	preempt_enable();
 }
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);