[PATCH V3 07/15] arch/kunmap_atomic: Consolidate duplicate code

From: ira . weiny
Date: Thu May 07 2020 - 11:00:26 EST


From: Ira Weiny <ira.weiny@xxxxxxxxx>

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.

Reviewed-by: Christoph Hellwig <hch@xxxxxx>
Signed-off-by: Ira Weiny <ira.weiny@xxxxxxxxx>

---
Changes from V1:
Adjust to preserve bisect-ability
Remove uneeded kunmap_atomic_high() declarations
---
arch/arc/include/asm/highmem.h | 2 --
arch/arc/mm/highmem.c | 7 ++-----
arch/arm/include/asm/highmem.h | 1 -
arch/arm/mm/highmem.c | 6 ++----
arch/csky/include/asm/highmem.h | 1 -
arch/csky/mm/highmem.c | 9 +++------
arch/microblaze/include/asm/highmem.h | 1 -
arch/microblaze/mm/highmem.c | 6 ++----
arch/mips/include/asm/highmem.h | 1 -
arch/mips/mm/cache.c | 4 ++--
arch/mips/mm/highmem.c | 6 ++----
arch/nds32/include/asm/highmem.h | 1 -
arch/nds32/mm/highmem.c | 6 ++----
arch/parisc/include/asm/cacheflush.h | 4 +---
arch/powerpc/include/asm/highmem.h | 1 -
arch/powerpc/mm/highmem.c | 6 ++----
arch/sparc/include/asm/highmem.h | 2 --
arch/sparc/mm/highmem.c | 6 ++----
arch/x86/include/asm/highmem.h | 1 -
arch/x86/mm/highmem_32.c | 7 ++-----
arch/xtensa/include/asm/highmem.h | 2 --
arch/xtensa/mm/highmem.c | 7 ++-----
include/linux/highmem.h | 11 +++++++----
23 files changed, 31 insertions(+), 67 deletions(-)

diff --git a/arch/arc/include/asm/highmem.h b/arch/arc/include/asm/highmem.h
index db425cd38545..70900a73bfc8 100644
--- a/arch/arc/include/asm/highmem.h
+++ b/arch/arc/include/asm/highmem.h
@@ -30,8 +30,6 @@

#include <asm/cacheflush.h>

-extern void __kunmap_atomic(void *kvaddr);
-
extern void kmap_init(void);

static inline void flush_cache_kmaps(void)
diff --git a/arch/arc/mm/highmem.c b/arch/arc/mm/highmem.c
index 0964b011c29f..5d3eab4ac0b0 100644
--- a/arch/arc/mm/highmem.c
+++ b/arch/arc/mm/highmem.c
@@ -65,7 +65,7 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kv)
+void kunmap_atomic_high(void *kv)
{
unsigned long kvaddr = (unsigned long)kv;

@@ -87,11 +87,8 @@ void __kunmap_atomic(void *kv)

kmap_atomic_idx_pop();
}
-
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

static noinline pte_t * __init alloc_kmap_pgtable(unsigned long kvaddr)
{
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index 8c80bfe18a34..b0d4bd8dc3c1 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -60,7 +60,6 @@ static inline void *kmap_high_get(struct page *page)
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
#endif

diff --git a/arch/arm/mm/highmem.c b/arch/arm/mm/highmem.c
index 075fdc235091..ac8394655a6e 100644
--- a/arch/arm/mm/highmem.c
+++ b/arch/arm/mm/highmem.c
@@ -73,7 +73,7 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
int idx, type;
@@ -95,10 +95,8 @@ void __kunmap_atomic(void *kvaddr)
/* this address was obtained through kmap_high_get() */
kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)]));
}
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

void *kmap_atomic_pfn(unsigned long pfn)
{
diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
index 8ceee12f9bc1..263fbddcd0a3 100644
--- a/arch/csky/include/asm/highmem.h
+++ b/arch/csky/include/asm/highmem.h
@@ -32,7 +32,6 @@ extern pte_t *pkmap_page_table;

#define ARCH_HAS_KMAP_FLUSH_TLB
extern void kmap_flush_tlb(unsigned long addr);
-extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
extern struct page *kmap_atomic_to_page(void *ptr);

diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
index 63d74b47eee6..0aafbbbe651c 100644
--- a/arch/csky/mm/highmem.c
+++ b/arch/csky/mm/highmem.c
@@ -39,13 +39,13 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
int idx;

if (vaddr < FIXADDR_START)
- goto out;
+ return;

#ifdef CONFIG_DEBUG_HIGHMEM
idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
@@ -58,11 +58,8 @@ void __kunmap_atomic(void *kvaddr)
(void) idx; /* to kill a warning */
#endif
kmap_atomic_idx_pop();
-out:
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

/*
* This is the same as kmap_atomic() but can map memory that doesn't
diff --git a/arch/microblaze/include/asm/highmem.h b/arch/microblaze/include/asm/highmem.h
index f7c5467df5ad..c3cbda90391d 100644
--- a/arch/microblaze/include/asm/highmem.h
+++ b/arch/microblaze/include/asm/highmem.h
@@ -61,7 +61,6 @@ 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/microblaze/mm/highmem.c b/arch/microblaze/mm/highmem.c
index 0e3efaa8a004..ee8a422b2b76 100644
--- a/arch/microblaze/mm/highmem.c
+++ b/arch/microblaze/mm/highmem.c
@@ -51,7 +51,7 @@ 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;
int type;
@@ -77,7 +77,5 @@ void __kunmap_atomic(void *kvaddr)
local_flush_tlb_page(NULL, vaddr);

kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/mips/include/asm/highmem.h b/arch/mips/include/asm/highmem.h
index 8bdbbfc322ad..76dec0bd4f59 100644
--- a/arch/mips/include/asm/highmem.h
+++ b/arch/mips/include/asm/highmem.h
@@ -48,7 +48,6 @@ extern pte_t *pkmap_page_table;

#define ARCH_HAS_KMAP_FLUSH_TLB
extern void kmap_flush_tlb(unsigned long addr);
-extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);

#define flush_cache_kmaps() BUG_ON(cpu_has_dc_aliases)
diff --git a/arch/mips/mm/cache.c b/arch/mips/mm/cache.c
index f015bb51fab0..1873c2a01fdb 100644
--- a/arch/mips/mm/cache.c
+++ b/arch/mips/mm/cache.c
@@ -104,7 +104,7 @@ void __flush_dcache_page(struct page *page)
flush_data_cache_page(addr);

if (PageHighMem(page))
- __kunmap_atomic((void *)addr);
+ kunmap_atomic((void *)addr);
}

EXPORT_SYMBOL(__flush_dcache_page);
@@ -147,7 +147,7 @@ void __update_cache(unsigned long address, pte_t pte)
flush_data_cache_page(addr);

if (PageHighMem(page))
- __kunmap_atomic((void *)addr);
+ kunmap_atomic((void *)addr);

ClearPageDcacheDirty(page);
}
diff --git a/arch/mips/mm/highmem.c b/arch/mips/mm/highmem.c
index 2bda56372995..155fbb107b35 100644
--- a/arch/mips/mm/highmem.c
+++ b/arch/mips/mm/highmem.c
@@ -36,7 +36,7 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
int type __maybe_unused;
@@ -63,10 +63,8 @@ void __kunmap_atomic(void *kvaddr)
}
#endif
kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

/*
* This is the same as kmap_atomic() but can map memory that doesn't
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h
index a3970e566ede..4d21308549c9 100644
--- a/arch/nds32/include/asm/highmem.h
+++ b/arch/nds32/include/asm/highmem.h
@@ -51,7 +51,6 @@ extern void kmap_init(void);
* when CONFIG_HIGHMEM is not set.
*/
#ifdef CONFIG_HIGHMEM
-extern void __kunmap_atomic(void *kvaddr);
extern void *kmap_atomic_pfn(unsigned long pfn);
extern struct page *kmap_atomic_to_page(void *ptr);
#endif
diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
index f5f3a21460c4..f6e6915c0d31 100644
--- a/arch/nds32/mm/highmem.c
+++ b/arch/nds32/mm/highmem.c
@@ -34,7 +34,7 @@ void *kmap_atomic_high(struct page *page)

EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
if (kvaddr >= (void *)FIXADDR_START) {
unsigned long vaddr = (unsigned long)kvaddr;
@@ -45,8 +45,6 @@ void __kunmap_atomic(void *kvaddr)
ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
set_pte(ptep, 0);
}
- pagefault_enable();
- preempt_enable();
}

-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/parisc/include/asm/cacheflush.h b/arch/parisc/include/asm/cacheflush.h
index 0c83644bfa5c..119c9a7681bc 100644
--- a/arch/parisc/include/asm/cacheflush.h
+++ b/arch/parisc/include/asm/cacheflush.h
@@ -122,11 +122,9 @@ static inline void *kmap_atomic(struct page *page)
return page_address(page);
}

-static inline void __kunmap_atomic(void *addr)
+static inline void kunmap_atomic_high(void *addr)
{
flush_kernel_dcache_page_addr(addr);
- pagefault_enable();
- preempt_enable();
}

#define kmap_atomic_prot(page, prot) kmap_atomic(page)
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..35071c2913f1 100644
--- a/arch/powerpc/mm/highmem.c
+++ b/arch/powerpc/mm/highmem.c
@@ -40,7 +40,7 @@ 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;

@@ -66,7 +66,5 @@ void __kunmap_atomic(void *kvaddr)
}

kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/sparc/include/asm/highmem.h b/arch/sparc/include/asm/highmem.h
index 458210c5bc38..f4babe67cb5d 100644
--- a/arch/sparc/include/asm/highmem.h
+++ b/arch/sparc/include/asm/highmem.h
@@ -50,8 +50,6 @@ void kmap_init(void) __init;

#define PKMAP_END (PKMAP_ADDR(LAST_PKMAP))

-void __kunmap_atomic(void *kvaddr);
-
#define flush_cache_kmaps() flush_cache_all()

#endif /* __KERNEL__ */
diff --git a/arch/sparc/mm/highmem.c b/arch/sparc/mm/highmem.c
index b53070ab6a31..469786bc430f 100644
--- a/arch/sparc/mm/highmem.c
+++ b/arch/sparc/mm/highmem.c
@@ -84,7 +84,7 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
int type;
@@ -126,7 +126,5 @@ void __kunmap_atomic(void *kvaddr)
#endif

kmap_atomic_idx_pop();
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);
diff --git a/arch/x86/include/asm/highmem.h b/arch/x86/include/asm/highmem.h
index 9393d55a2adb..be66b77885a0 100644
--- a/arch/x86/include/asm/highmem.h
+++ b/arch/x86/include/asm/highmem.h
@@ -72,7 +72,6 @@ static inline void *kmap_atomic_high(struct page *page)
{
return kmap_atomic_high_prot(page, kmap_prot);
}
-void __kunmap_atomic(void *kvaddr);
void *kmap_atomic_pfn(unsigned long pfn);
void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot);

diff --git a/arch/x86/mm/highmem_32.c b/arch/x86/mm/highmem_32.c
index c3e272a759e0..075fe51317b0 100644
--- a/arch/x86/mm/highmem_32.c
+++ b/arch/x86/mm/highmem_32.c
@@ -30,7 +30,7 @@ void *kmap_atomic_pfn(unsigned long pfn)
}
EXPORT_SYMBOL_GPL(kmap_atomic_pfn);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;

@@ -60,11 +60,8 @@ void __kunmap_atomic(void *kvaddr)
BUG_ON(vaddr >= (unsigned long)high_memory);
}
#endif
-
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

void __init set_highmem_pages_init(void)
{
diff --git a/arch/xtensa/include/asm/highmem.h b/arch/xtensa/include/asm/highmem.h
index 1e6aa15c4bdf..d6a10704307a 100644
--- a/arch/xtensa/include/asm/highmem.h
+++ b/arch/xtensa/include/asm/highmem.h
@@ -68,8 +68,6 @@ static inline void flush_cache_kmaps(void)
flush_cache_all();
}

-void __kunmap_atomic(void *kvaddr);
-
void kmap_init(void);

#endif
diff --git a/arch/xtensa/mm/highmem.c b/arch/xtensa/mm/highmem.c
index 90b85a897cb0..4de323e43682 100644
--- a/arch/xtensa/mm/highmem.c
+++ b/arch/xtensa/mm/highmem.c
@@ -54,7 +54,7 @@ void *kmap_atomic_high(struct page *page)
}
EXPORT_SYMBOL(kmap_atomic_high);

-void __kunmap_atomic(void *kvaddr)
+void kunmap_atomic_high(void *kvaddr)
{
if (kvaddr >= (void *)FIXADDR_START &&
kvaddr < (void *)FIXADDR_TOP) {
@@ -73,11 +73,8 @@ void __kunmap_atomic(void *kvaddr)

kmap_atomic_idx_pop();
}
-
- pagefault_enable();
- preempt_enable();
}
-EXPORT_SYMBOL(__kunmap_atomic);
+EXPORT_SYMBOL(kunmap_atomic_high);

void __init kmap_init(void)
{
diff --git a/include/linux/highmem.h b/include/linux/highmem.h
index 86b93dee758a..c36c0ee09423 100644
--- a/include/linux/highmem.h
+++ b/include/linux/highmem.h
@@ -33,6 +33,7 @@ static inline void invalidate_kernel_vmap_range(void *vaddr, int size)

#ifdef CONFIG_HIGHMEM
extern void *kmap_atomic_high(struct page *page);
+extern void kunmap_atomic_high(void *kvaddr);
#include <asm/highmem.h>

#ifndef ARCH_HAS_KMAP_FLUSH_TLB
@@ -146,10 +147,10 @@ static inline void *kmap_atomic(struct page *page)
}
#define kmap_atomic_prot(page, prot) kmap_atomic(page)

-static inline void __kunmap_atomic(void *addr)
+static inline void kunmap_atomic_high(void *addr)
{
- pagefault_enable();
- preempt_enable();
+ /* Nothing to do in the CONFIG_HIGHMEM=n case as kunmap_atomic()
+ * handles re-enabling faults + preemption */
}

#define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn))
@@ -199,7 +200,9 @@ static inline void kmap_atomic_idx_pop(void)
#define kunmap_atomic(addr) \
do { \
BUILD_BUG_ON(__same_type((addr), struct page *)); \
- __kunmap_atomic(addr); \
+ kunmap_atomic_high(addr); \
+ pagefault_enable(); \
+ preempt_enable(); \
} while (0)


--
2.25.1