thr3ads.net - Linux Virtualization - [PATCH v3 0/4] iomap: Constify ioreadX() iomem argument [Jul 2020]

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Krzysztof Kozlowski

2020-Jul-09 07:28 UTC

[PATCH v3 0/4] iomap: Constify ioreadX() iomem argument

Hi,

Multiple architectures are affected in the first patch and all further
patches depend on the first.

Maybe this could go in through Andrew Morton's tree?


Changes since v2
===============1. Drop all non-essential patches (cleanups),
2. Update also drivers/sh/clk/cpg.c .


Changes since v1
===============https://lore.kernel.org/lkml/1578415992-24054-1-git-send-email-krzk
at kernel.org/
1. Constify also ioreadX_rep() and mmio_insX(),
2. Squash lib+alpha+powerpc+parisc+sh into one patch for bisectability,
3. Add acks and reviews,
4. Re-order patches so all optional driver changes are at the end.


Description
==========The ioread8/16/32() and others have inconsistent interface among the
architectures: some taking address as const, some not.

It seems there is nothing really stopping all of them to take
pointer to const.

Patchset was only compile tested on affected architectures.  No real
testing.


volatile
=======There is still interface inconsistency between architectures around
"volatile" qualifier:
 - include/asm-generic/io.h:static inline u32 ioread32(const volatile void
__iomem *addr)
 - include/asm-generic/iomap.h:extern unsigned int ioread32(const void __iomem
*);

This is still discussed and out of scope of this patchset.


Best regards,
Krzysztof


Krzysztof Kozlowski (4):
  iomap: Constify ioreadX() iomem argument (as in generic
    implementation)
  rtl818x: Constify ioreadX() iomem argument (as in generic
    implementation)
  ntb: intel: Constify ioreadX() iomem argument (as in generic
    implementation)
  virtio: pci: Constify ioreadX() iomem argument (as in generic
    implementation)

 arch/alpha/include/asm/core_apecs.h           |  6 +-
 arch/alpha/include/asm/core_cia.h             |  6 +-
 arch/alpha/include/asm/core_lca.h             |  6 +-
 arch/alpha/include/asm/core_marvel.h          |  4 +-
 arch/alpha/include/asm/core_mcpcia.h          |  6 +-
 arch/alpha/include/asm/core_t2.h              |  2 +-
 arch/alpha/include/asm/io.h                   | 12 ++--
 arch/alpha/include/asm/io_trivial.h           | 16 ++---
 arch/alpha/include/asm/jensen.h               |  2 +-
 arch/alpha/include/asm/machvec.h              |  6 +-
 arch/alpha/kernel/core_marvel.c               |  2 +-
 arch/alpha/kernel/io.c                        | 12 ++--
 arch/parisc/include/asm/io.h                  |  4 +-
 arch/parisc/lib/iomap.c                       | 72 +++++++++----------
 arch/powerpc/kernel/iomap.c                   | 28 ++++----
 arch/sh/kernel/iomap.c                        | 22 +++---
 .../realtek/rtl818x/rtl8180/rtl8180.h         |  6 +-
 drivers/ntb/hw/intel/ntb_hw_gen1.c            |  2 +-
 drivers/ntb/hw/intel/ntb_hw_gen3.h            |  2 +-
 drivers/ntb/hw/intel/ntb_hw_intel.h           |  2 +-
 drivers/sh/clk/cpg.c                          |  2 +-
 drivers/virtio/virtio_pci_modern.c            |  6 +-
 include/asm-generic/iomap.h                   | 28 ++++----
 include/linux/io-64-nonatomic-hi-lo.h         |  4 +-
 include/linux/io-64-nonatomic-lo-hi.h         |  4 +-
 lib/iomap.c                                   | 30 ++++----
 26 files changed, 146 insertions(+), 146 deletions(-)

-- 
2.17.1

Krzysztof Kozlowski

2020-Jul-09 07:28 UTC

head link

[PATCH v3 1/4] iomap: Constify ioreadX() iomem argument (as in generic implementation)

The ioreadX() and ioreadX_rep() helpers have inconsistent interface.  On
some architectures void *__iomem address argument is a pointer to const,
on some not.

Implementations of ioreadX() do not modify the memory under the address
so they can be converted to a "const" version for const-safety and
consistency among architectures.

Suggested-by: Geert Uytterhoeven <geert at linux-m68k.org>
Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
Reviewed-by: Arnd Bergmann <arnd at arndb.de>
---
 arch/alpha/include/asm/core_apecs.h   |  6 +--
 arch/alpha/include/asm/core_cia.h     |  6 +--
 arch/alpha/include/asm/core_lca.h     |  6 +--
 arch/alpha/include/asm/core_marvel.h  |  4 +-
 arch/alpha/include/asm/core_mcpcia.h  |  6 +--
 arch/alpha/include/asm/core_t2.h      |  2 +-
 arch/alpha/include/asm/io.h           | 12 ++---
 arch/alpha/include/asm/io_trivial.h   | 16 +++---
 arch/alpha/include/asm/jensen.h       |  2 +-
 arch/alpha/include/asm/machvec.h      |  6 +--
 arch/alpha/kernel/core_marvel.c       |  2 +-
 arch/alpha/kernel/io.c                | 12 ++---
 arch/parisc/include/asm/io.h          |  4 +-
 arch/parisc/lib/iomap.c               | 72 +++++++++++++--------------
 arch/powerpc/kernel/iomap.c           | 28 +++++------
 arch/sh/kernel/iomap.c                | 22 ++++----
 drivers/sh/clk/cpg.c                  |  2 +-
 include/asm-generic/iomap.h           | 28 +++++------
 include/linux/io-64-nonatomic-hi-lo.h |  4 +-
 include/linux/io-64-nonatomic-lo-hi.h |  4 +-
 lib/iomap.c                           | 30 +++++------
 21 files changed, 137 insertions(+), 137 deletions(-)

diff --git a/arch/alpha/include/asm/core_apecs.h
b/arch/alpha/include/asm/core_apecs.h
index 0a07055bc0fe..2d9726fc02ef 100644
--- a/arch/alpha/include/asm/core_apecs.h
+++ b/arch/alpha/include/asm/core_apecs.h
@@ -384,7 +384,7 @@ struct el_apecs_procdata
 		}						\
 	} while (0)
 
-__EXTERN_INLINE unsigned int apecs_ioread8(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int apecs_ioread8(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -420,7 +420,7 @@ __EXTERN_INLINE void apecs_iowrite8(u8 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int apecs_ioread16(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int apecs_ioread16(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -456,7 +456,7 @@ __EXTERN_INLINE void apecs_iowrite16(u16 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int apecs_ioread32(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int apecs_ioread32(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	if (addr < APECS_DENSE_MEM)
diff --git a/arch/alpha/include/asm/core_cia.h
b/arch/alpha/include/asm/core_cia.h
index c706a7f2b061..cb22991f6761 100644
--- a/arch/alpha/include/asm/core_cia.h
+++ b/arch/alpha/include/asm/core_cia.h
@@ -342,7 +342,7 @@ struct el_CIA_sysdata_mcheck {
 #define vuip	volatile unsigned int __force *
 #define vulp	volatile unsigned long __force *
 
-__EXTERN_INLINE unsigned int cia_ioread8(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int cia_ioread8(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -374,7 +374,7 @@ __EXTERN_INLINE void cia_iowrite8(u8 b, void __iomem *xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int cia_ioread16(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int cia_ioread16(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -404,7 +404,7 @@ __EXTERN_INLINE void cia_iowrite16(u16 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int cia_ioread32(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int cia_ioread32(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	if (addr < CIA_DENSE_MEM)
diff --git a/arch/alpha/include/asm/core_lca.h
b/arch/alpha/include/asm/core_lca.h
index 84d5e5b84f4f..ec86314418cb 100644
--- a/arch/alpha/include/asm/core_lca.h
+++ b/arch/alpha/include/asm/core_lca.h
@@ -230,7 +230,7 @@ union el_lca {
 	} while (0)
 
 
-__EXTERN_INLINE unsigned int lca_ioread8(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int lca_ioread8(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -266,7 +266,7 @@ __EXTERN_INLINE void lca_iowrite8(u8 b, void __iomem *xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int lca_ioread16(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int lca_ioread16(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	unsigned long result, base_and_type;
@@ -302,7 +302,7 @@ __EXTERN_INLINE void lca_iowrite16(u16 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + base_and_type) = w;
 }
 
-__EXTERN_INLINE unsigned int lca_ioread32(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int lca_ioread32(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	if (addr < LCA_DENSE_MEM)
diff --git a/arch/alpha/include/asm/core_marvel.h
b/arch/alpha/include/asm/core_marvel.h
index cc6fd92d5fa9..b266e02e284b 100644
--- a/arch/alpha/include/asm/core_marvel.h
+++ b/arch/alpha/include/asm/core_marvel.h
@@ -332,10 +332,10 @@ struct io7 {
 #define vucp	volatile unsigned char __force *
 #define vusp	volatile unsigned short __force *
 
-extern unsigned int marvel_ioread8(void __iomem *);
+extern unsigned int marvel_ioread8(const void __iomem *);
 extern void marvel_iowrite8(u8 b, void __iomem *);
 
-__EXTERN_INLINE unsigned int marvel_ioread16(void __iomem *addr)
+__EXTERN_INLINE unsigned int marvel_ioread16(const void __iomem *addr)
 {
 	return __kernel_ldwu(*(vusp)addr);
 }
diff --git a/arch/alpha/include/asm/core_mcpcia.h
b/arch/alpha/include/asm/core_mcpcia.h
index b30dc128210d..cb24d1bd6141 100644
--- a/arch/alpha/include/asm/core_mcpcia.h
+++ b/arch/alpha/include/asm/core_mcpcia.h
@@ -267,7 +267,7 @@ extern inline int __mcpcia_is_mmio(unsigned long addr)
 	return (addr & 0x80000000UL) == 0;
 }
 
-__EXTERN_INLINE unsigned int mcpcia_ioread8(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int mcpcia_ioread8(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long)xaddr & MCPCIA_MEM_MASK;
 	unsigned long hose = (unsigned long)xaddr & ~MCPCIA_MEM_MASK;
@@ -291,7 +291,7 @@ __EXTERN_INLINE void mcpcia_iowrite8(u8 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + hose + 0x00) = w;
 }
 
-__EXTERN_INLINE unsigned int mcpcia_ioread16(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int mcpcia_ioread16(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long)xaddr & MCPCIA_MEM_MASK;
 	unsigned long hose = (unsigned long)xaddr & ~MCPCIA_MEM_MASK;
@@ -315,7 +315,7 @@ __EXTERN_INLINE void mcpcia_iowrite16(u16 b, void __iomem
*xaddr)
 	*(vuip) ((addr << 5) + hose + 0x08) = w;
 }
 
-__EXTERN_INLINE unsigned int mcpcia_ioread32(void __iomem *xaddr)
+__EXTERN_INLINE unsigned int mcpcia_ioread32(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long)xaddr;
 
diff --git a/arch/alpha/include/asm/core_t2.h b/arch/alpha/include/asm/core_t2.h
index e0b33d09e93a..12bb7addc789 100644
--- a/arch/alpha/include/asm/core_t2.h
+++ b/arch/alpha/include/asm/core_t2.h
@@ -572,7 +572,7 @@ __EXTERN_INLINE int t2_is_mmio(const volatile void __iomem
*addr)
    it doesn't make sense to merge the pio and mmio routines.  */
 
 #define IOPORT(OS, NS)							\
-__EXTERN_INLINE unsigned int t2_ioread##NS(void __iomem *xaddr)		\
+__EXTERN_INLINE unsigned int t2_ioread##NS(const void __iomem *xaddr)		\
 {									\
 	if (t2_is_mmio(xaddr))						\
 		return t2_read##OS(xaddr);				\
diff --git a/arch/alpha/include/asm/io.h b/arch/alpha/include/asm/io.h
index 640e1a2f57b4..1f6a909d1fa5 100644
--- a/arch/alpha/include/asm/io.h
+++ b/arch/alpha/include/asm/io.h
@@ -150,9 +150,9 @@ static inline void generic_##NAME(TYPE b, QUAL void __iomem
*addr)	\
 	alpha_mv.mv_##NAME(b, addr);					\
 }
 
-REMAP1(unsigned int, ioread8, /**/)
-REMAP1(unsigned int, ioread16, /**/)
-REMAP1(unsigned int, ioread32, /**/)
+REMAP1(unsigned int, ioread8, const)
+REMAP1(unsigned int, ioread16, const)
+REMAP1(unsigned int, ioread32, const)
 REMAP1(u8, readb, const volatile)
 REMAP1(u16, readw, const volatile)
 REMAP1(u32, readl, const volatile)
@@ -307,7 +307,7 @@ static inline int __is_mmio(const volatile void __iomem
*addr)
  */
 
 #if IO_CONCAT(__IO_PREFIX,trivial_io_bw)
-extern inline unsigned int ioread8(void __iomem *addr)
+extern inline unsigned int ioread8(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
@@ -316,7 +316,7 @@ extern inline unsigned int ioread8(void __iomem *addr)
 	return ret;
 }
 
-extern inline unsigned int ioread16(void __iomem *addr)
+extern inline unsigned int ioread16(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
@@ -359,7 +359,7 @@ extern inline void outw(u16 b, unsigned long port)
 #endif
 
 #if IO_CONCAT(__IO_PREFIX,trivial_io_lq)
-extern inline unsigned int ioread32(void __iomem *addr)
+extern inline unsigned int ioread32(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
diff --git a/arch/alpha/include/asm/io_trivial.h
b/arch/alpha/include/asm/io_trivial.h
index ba3d8f0cfe0c..a1a29cbe02fa 100644
--- a/arch/alpha/include/asm/io_trivial.h
+++ b/arch/alpha/include/asm/io_trivial.h
@@ -7,15 +7,15 @@
 
 #if IO_CONCAT(__IO_PREFIX,trivial_io_bw)
 __EXTERN_INLINE unsigned int
-IO_CONCAT(__IO_PREFIX,ioread8)(void __iomem *a)
+IO_CONCAT(__IO_PREFIX,ioread8)(const void __iomem *a)
 {
-	return __kernel_ldbu(*(volatile u8 __force *)a);
+	return __kernel_ldbu(*(const volatile u8 __force *)a);
 }
 
 __EXTERN_INLINE unsigned int
-IO_CONCAT(__IO_PREFIX,ioread16)(void __iomem *a)
+IO_CONCAT(__IO_PREFIX,ioread16)(const void __iomem *a)
 {
-	return __kernel_ldwu(*(volatile u16 __force *)a);
+	return __kernel_ldwu(*(const volatile u16 __force *)a);
 }
 
 __EXTERN_INLINE void
@@ -33,9 +33,9 @@ IO_CONCAT(__IO_PREFIX,iowrite16)(u16 b, void __iomem *a)
 
 #if IO_CONCAT(__IO_PREFIX,trivial_io_lq)
 __EXTERN_INLINE unsigned int
-IO_CONCAT(__IO_PREFIX,ioread32)(void __iomem *a)
+IO_CONCAT(__IO_PREFIX,ioread32)(const void __iomem *a)
 {
-	return *(volatile u32 __force *)a;
+	return *(const volatile u32 __force *)a;
 }
 
 __EXTERN_INLINE void
@@ -73,14 +73,14 @@ IO_CONCAT(__IO_PREFIX,writew)(u16 b, volatile void __iomem
*a)
 __EXTERN_INLINE u8
 IO_CONCAT(__IO_PREFIX,readb)(const volatile void __iomem *a)
 {
-	void __iomem *addr = (void __iomem *)a;
+	const void __iomem *addr = (const void __iomem *)a;
 	return IO_CONCAT(__IO_PREFIX,ioread8)(addr);
 }
 
 __EXTERN_INLINE u16
 IO_CONCAT(__IO_PREFIX,readw)(const volatile void __iomem *a)
 {
-	void __iomem *addr = (void __iomem *)a;
+	const void __iomem *addr = (const void __iomem *)a;
 	return IO_CONCAT(__IO_PREFIX,ioread16)(addr);
 }
 
diff --git a/arch/alpha/include/asm/jensen.h b/arch/alpha/include/asm/jensen.h
index 436dc905b6ad..916895155a88 100644
--- a/arch/alpha/include/asm/jensen.h
+++ b/arch/alpha/include/asm/jensen.h
@@ -305,7 +305,7 @@ __EXTERN_INLINE int jensen_is_mmio(const volatile void
__iomem *addr)
    that it doesn't make sense to merge them.  */
 
 #define IOPORT(OS, NS)							\
-__EXTERN_INLINE unsigned int jensen_ioread##NS(void __iomem *xaddr)	\
+__EXTERN_INLINE unsigned int jensen_ioread##NS(const void __iomem *xaddr)	\
 {									\
 	if (jensen_is_mmio(xaddr))					\
 		return jensen_read##OS(xaddr - 0x100000000ul);		\
diff --git a/arch/alpha/include/asm/machvec.h b/arch/alpha/include/asm/machvec.h
index a6b73c6d10ee..a4e96e2bec74 100644
--- a/arch/alpha/include/asm/machvec.h
+++ b/arch/alpha/include/asm/machvec.h
@@ -46,9 +46,9 @@ struct alpha_machine_vector
 	void (*mv_pci_tbi)(struct pci_controller *hose,
 			   dma_addr_t start, dma_addr_t end);
 
-	unsigned int (*mv_ioread8)(void __iomem *);
-	unsigned int (*mv_ioread16)(void __iomem *);
-	unsigned int (*mv_ioread32)(void __iomem *);
+	unsigned int (*mv_ioread8)(const void __iomem *);
+	unsigned int (*mv_ioread16)(const void __iomem *);
+	unsigned int (*mv_ioread32)(const void __iomem *);
 
 	void (*mv_iowrite8)(u8, void __iomem *);
 	void (*mv_iowrite16)(u16, void __iomem *);
diff --git a/arch/alpha/kernel/core_marvel.c b/arch/alpha/kernel/core_marvel.c
index 4c80d992a659..4485b77f8658 100644
--- a/arch/alpha/kernel/core_marvel.c
+++ b/arch/alpha/kernel/core_marvel.c
@@ -806,7 +806,7 @@ void __iomem *marvel_ioportmap (unsigned long addr)
 }
 
 unsigned int
-marvel_ioread8(void __iomem *xaddr)
+marvel_ioread8(const void __iomem *xaddr)
 {
 	unsigned long addr = (unsigned long) xaddr;
 	if (__marvel_is_port_kbd(addr))
diff --git a/arch/alpha/kernel/io.c b/arch/alpha/kernel/io.c
index 938de13adfbf..838586abb1e0 100644
--- a/arch/alpha/kernel/io.c
+++ b/arch/alpha/kernel/io.c
@@ -14,7 +14,7 @@
    "generic", which bumps through the machine vector.  */
 
 unsigned int
-ioread8(void __iomem *addr)
+ioread8(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
@@ -23,7 +23,7 @@ ioread8(void __iomem *addr)
 	return ret;
 }
 
-unsigned int ioread16(void __iomem *addr)
+unsigned int ioread16(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
@@ -32,7 +32,7 @@ unsigned int ioread16(void __iomem *addr)
 	return ret;
 }
 
-unsigned int ioread32(void __iomem *addr)
+unsigned int ioread32(const void __iomem *addr)
 {
 	unsigned int ret;
 	mb();
@@ -257,7 +257,7 @@ EXPORT_SYMBOL(readq_relaxed);
 /*
  * Read COUNT 8-bit bytes from port PORT into memory starting at SRC.
  */
-void ioread8_rep(void __iomem *port, void *dst, unsigned long count)
+void ioread8_rep(const void __iomem *port, void *dst, unsigned long count)
 {
 	while ((unsigned long)dst & 0x3) {
 		if (!count)
@@ -300,7 +300,7 @@ EXPORT_SYMBOL(insb);
  * the interfaces seems to be slow: just using the inlined version
  * of the inw() breaks things.
  */
-void ioread16_rep(void __iomem *port, void *dst, unsigned long count)
+void ioread16_rep(const void __iomem *port, void *dst, unsigned long count)
 {
 	if (unlikely((unsigned long)dst & 0x3)) {
 		if (!count)
@@ -340,7 +340,7 @@ EXPORT_SYMBOL(insw);
  * but the interfaces seems to be slow: just using the inlined version
  * of the inl() breaks things.
  */
-void ioread32_rep(void __iomem *port, void *dst, unsigned long count)
+void ioread32_rep(const void __iomem *port, void *dst, unsigned long count)
 {
 	if (unlikely((unsigned long)dst & 0x3)) {
 		while (count--) {
diff --git a/arch/parisc/include/asm/io.h b/arch/parisc/include/asm/io.h
index 116effe26143..45e20d38dc59 100644
--- a/arch/parisc/include/asm/io.h
+++ b/arch/parisc/include/asm/io.h
@@ -303,8 +303,8 @@ extern void outsl (unsigned long port, const void *src,
unsigned long count);
 #define ioread64be ioread64be
 #define iowrite64 iowrite64
 #define iowrite64be iowrite64be
-extern u64 ioread64(void __iomem *addr);
-extern u64 ioread64be(void __iomem *addr);
+extern u64 ioread64(const void __iomem *addr);
+extern u64 ioread64be(const void __iomem *addr);
 extern void iowrite64(u64 val, void __iomem *addr);
 extern void iowrite64be(u64 val, void __iomem *addr);
 
diff --git a/arch/parisc/lib/iomap.c b/arch/parisc/lib/iomap.c
index 0195aec657e2..ce400417d54e 100644
--- a/arch/parisc/lib/iomap.c
+++ b/arch/parisc/lib/iomap.c
@@ -43,13 +43,13 @@
 #endif
 
 struct iomap_ops {
-	unsigned int (*read8)(void __iomem *);
-	unsigned int (*read16)(void __iomem *);
-	unsigned int (*read16be)(void __iomem *);
-	unsigned int (*read32)(void __iomem *);
-	unsigned int (*read32be)(void __iomem *);
-	u64 (*read64)(void __iomem *);
-	u64 (*read64be)(void __iomem *);
+	unsigned int (*read8)(const void __iomem *);
+	unsigned int (*read16)(const void __iomem *);
+	unsigned int (*read16be)(const void __iomem *);
+	unsigned int (*read32)(const void __iomem *);
+	unsigned int (*read32be)(const void __iomem *);
+	u64 (*read64)(const void __iomem *);
+	u64 (*read64be)(const void __iomem *);
 	void (*write8)(u8, void __iomem *);
 	void (*write16)(u16, void __iomem *);
 	void (*write16be)(u16, void __iomem *);
@@ -57,9 +57,9 @@ struct iomap_ops {
 	void (*write32be)(u32, void __iomem *);
 	void (*write64)(u64, void __iomem *);
 	void (*write64be)(u64, void __iomem *);
-	void (*read8r)(void __iomem *, void *, unsigned long);
-	void (*read16r)(void __iomem *, void *, unsigned long);
-	void (*read32r)(void __iomem *, void *, unsigned long);
+	void (*read8r)(const void __iomem *, void *, unsigned long);
+	void (*read16r)(const void __iomem *, void *, unsigned long);
+	void (*read32r)(const void __iomem *, void *, unsigned long);
 	void (*write8r)(void __iomem *, const void *, unsigned long);
 	void (*write16r)(void __iomem *, const void *, unsigned long);
 	void (*write32r)(void __iomem *, const void *, unsigned long);
@@ -69,17 +69,17 @@ struct iomap_ops {
 
 #define ADDR2PORT(addr) ((unsigned long __force)(addr) & 0xffffff)
 
-static unsigned int ioport_read8(void __iomem *addr)
+static unsigned int ioport_read8(const void __iomem *addr)
 {
 	return inb(ADDR2PORT(addr));
 }
 
-static unsigned int ioport_read16(void __iomem *addr)
+static unsigned int ioport_read16(const void __iomem *addr)
 {
 	return inw(ADDR2PORT(addr));
 }
 
-static unsigned int ioport_read32(void __iomem *addr)
+static unsigned int ioport_read32(const void __iomem *addr)
 {
 	return inl(ADDR2PORT(addr));
 }
@@ -99,17 +99,17 @@ static void ioport_write32(u32 datum, void __iomem *addr)
 	outl(datum, ADDR2PORT(addr));
 }
 
-static void ioport_read8r(void __iomem *addr, void *dst, unsigned long count)
+static void ioport_read8r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	insb(ADDR2PORT(addr), dst, count);
 }
 
-static void ioport_read16r(void __iomem *addr, void *dst, unsigned long count)
+static void ioport_read16r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	insw(ADDR2PORT(addr), dst, count);
 }
 
-static void ioport_read32r(void __iomem *addr, void *dst, unsigned long count)
+static void ioport_read32r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	insl(ADDR2PORT(addr), dst, count);
 }
@@ -150,37 +150,37 @@ static const struct iomap_ops ioport_ops = {
 
 /* Legacy I/O memory ops */
 
-static unsigned int iomem_read8(void __iomem *addr)
+static unsigned int iomem_read8(const void __iomem *addr)
 {
 	return readb(addr);
 }
 
-static unsigned int iomem_read16(void __iomem *addr)
+static unsigned int iomem_read16(const void __iomem *addr)
 {
 	return readw(addr);
 }
 
-static unsigned int iomem_read16be(void __iomem *addr)
+static unsigned int iomem_read16be(const void __iomem *addr)
 {
 	return __raw_readw(addr);
 }
 
-static unsigned int iomem_read32(void __iomem *addr)
+static unsigned int iomem_read32(const void __iomem *addr)
 {
 	return readl(addr);
 }
 
-static unsigned int iomem_read32be(void __iomem *addr)
+static unsigned int iomem_read32be(const void __iomem *addr)
 {
 	return __raw_readl(addr);
 }
 
-static u64 iomem_read64(void __iomem *addr)
+static u64 iomem_read64(const void __iomem *addr)
 {
 	return readq(addr);
 }
 
-static u64 iomem_read64be(void __iomem *addr)
+static u64 iomem_read64be(const void __iomem *addr)
 {
 	return __raw_readq(addr);
 }
@@ -220,7 +220,7 @@ static void iomem_write64be(u64 datum, void __iomem *addr)
 	__raw_writel(datum, addr);
 }
 
-static void iomem_read8r(void __iomem *addr, void *dst, unsigned long count)
+static void iomem_read8r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	while (count--) {
 		*(u8 *)dst = __raw_readb(addr);
@@ -228,7 +228,7 @@ static void iomem_read8r(void __iomem *addr, void *dst,
unsigned long count)
 	}
 }
 
-static void iomem_read16r(void __iomem *addr, void *dst, unsigned long count)
+static void iomem_read16r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	while (count--) {
 		*(u16 *)dst = __raw_readw(addr);
@@ -236,7 +236,7 @@ static void iomem_read16r(void __iomem *addr, void *dst,
unsigned long count)
 	}
 }
 
-static void iomem_read32r(void __iomem *addr, void *dst, unsigned long count)
+static void iomem_read32r(const void __iomem *addr, void *dst, unsigned long
count)
 {
 	while (count--) {
 		*(u32 *)dst = __raw_readl(addr);
@@ -297,49 +297,49 @@ static const struct iomap_ops *iomap_ops[8] = {
 };
 
 
-unsigned int ioread8(void __iomem *addr)
+unsigned int ioread8(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read8(addr);
 	return *((u8 *)addr);
 }
 
-unsigned int ioread16(void __iomem *addr)
+unsigned int ioread16(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read16(addr);
 	return le16_to_cpup((u16 *)addr);
 }
 
-unsigned int ioread16be(void __iomem *addr)
+unsigned int ioread16be(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read16be(addr);
 	return *((u16 *)addr);
 }
 
-unsigned int ioread32(void __iomem *addr)
+unsigned int ioread32(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read32(addr);
 	return le32_to_cpup((u32 *)addr);
 }
 
-unsigned int ioread32be(void __iomem *addr)
+unsigned int ioread32be(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read32be(addr);
 	return *((u32 *)addr);
 }
 
-u64 ioread64(void __iomem *addr)
+u64 ioread64(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read64(addr);
 	return le64_to_cpup((u64 *)addr);
 }
 
-u64 ioread64be(void __iomem *addr)
+u64 ioread64be(const void __iomem *addr)
 {
 	if (unlikely(INDIRECT_ADDR(addr)))
 		return iomap_ops[ADDR_TO_REGION(addr)]->read64be(addr);
@@ -411,7 +411,7 @@ void iowrite64be(u64 datum, void __iomem *addr)
 
 /* Repeating interfaces */
 
-void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	if (unlikely(INDIRECT_ADDR(addr))) {
 		iomap_ops[ADDR_TO_REGION(addr)]->read8r(addr, dst, count);
@@ -423,7 +423,7 @@ void ioread8_rep(void __iomem *addr, void *dst, unsigned
long count)
 	}
 }
 
-void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	if (unlikely(INDIRECT_ADDR(addr))) {
 		iomap_ops[ADDR_TO_REGION(addr)]->read16r(addr, dst, count);
@@ -435,7 +435,7 @@ void ioread16_rep(void __iomem *addr, void *dst, unsigned
long count)
 	}
 }
 
-void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	if (unlikely(INDIRECT_ADDR(addr))) {
 		iomap_ops[ADDR_TO_REGION(addr)]->read32r(addr, dst, count);
diff --git a/arch/powerpc/kernel/iomap.c b/arch/powerpc/kernel/iomap.c
index 5ac84efc6ede..9fe4fb3b08aa 100644
--- a/arch/powerpc/kernel/iomap.c
+++ b/arch/powerpc/kernel/iomap.c
@@ -15,23 +15,23 @@
  * Here comes the ppc64 implementation of the IOMAP 
  * interfaces.
  */
-unsigned int ioread8(void __iomem *addr)
+unsigned int ioread8(const void __iomem *addr)
 {
 	return readb(addr);
 }
-unsigned int ioread16(void __iomem *addr)
+unsigned int ioread16(const void __iomem *addr)
 {
 	return readw(addr);
 }
-unsigned int ioread16be(void __iomem *addr)
+unsigned int ioread16be(const void __iomem *addr)
 {
 	return readw_be(addr);
 }
-unsigned int ioread32(void __iomem *addr)
+unsigned int ioread32(const void __iomem *addr)
 {
 	return readl(addr);
 }
-unsigned int ioread32be(void __iomem *addr)
+unsigned int ioread32be(const void __iomem *addr)
 {
 	return readl_be(addr);
 }
@@ -41,27 +41,27 @@ EXPORT_SYMBOL(ioread16be);
 EXPORT_SYMBOL(ioread32);
 EXPORT_SYMBOL(ioread32be);
 #ifdef __powerpc64__
-u64 ioread64(void __iomem *addr)
+u64 ioread64(const void __iomem *addr)
 {
 	return readq(addr);
 }
-u64 ioread64_lo_hi(void __iomem *addr)
+u64 ioread64_lo_hi(const void __iomem *addr)
 {
 	return readq(addr);
 }
-u64 ioread64_hi_lo(void __iomem *addr)
+u64 ioread64_hi_lo(const void __iomem *addr)
 {
 	return readq(addr);
 }
-u64 ioread64be(void __iomem *addr)
+u64 ioread64be(const void __iomem *addr)
 {
 	return readq_be(addr);
 }
-u64 ioread64be_lo_hi(void __iomem *addr)
+u64 ioread64be_lo_hi(const void __iomem *addr)
 {
 	return readq_be(addr);
 }
-u64 ioread64be_hi_lo(void __iomem *addr)
+u64 ioread64be_hi_lo(const void __iomem *addr)
 {
 	return readq_be(addr);
 }
@@ -139,15 +139,15 @@ EXPORT_SYMBOL(iowrite64be_hi_lo);
  * FIXME! We could make these do EEH handling if we really
  * wanted. Not clear if we do.
  */
-void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	readsb(addr, dst, count);
 }
-void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	readsw(addr, dst, count);
 }
-void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	readsl(addr, dst, count);
 }
diff --git a/arch/sh/kernel/iomap.c b/arch/sh/kernel/iomap.c
index ef9e2c97cbb7..0a0dff4e66de 100644
--- a/arch/sh/kernel/iomap.c
+++ b/arch/sh/kernel/iomap.c
@@ -8,31 +8,31 @@
 #include <linux/module.h>
 #include <linux/io.h>
 
-unsigned int ioread8(void __iomem *addr)
+unsigned int ioread8(const void __iomem *addr)
 {
 	return readb(addr);
 }
 EXPORT_SYMBOL(ioread8);
 
-unsigned int ioread16(void __iomem *addr)
+unsigned int ioread16(const void __iomem *addr)
 {
 	return readw(addr);
 }
 EXPORT_SYMBOL(ioread16);
 
-unsigned int ioread16be(void __iomem *addr)
+unsigned int ioread16be(const void __iomem *addr)
 {
 	return be16_to_cpu(__raw_readw(addr));
 }
 EXPORT_SYMBOL(ioread16be);
 
-unsigned int ioread32(void __iomem *addr)
+unsigned int ioread32(const void __iomem *addr)
 {
 	return readl(addr);
 }
 EXPORT_SYMBOL(ioread32);
 
-unsigned int ioread32be(void __iomem *addr)
+unsigned int ioread32be(const void __iomem *addr)
 {
 	return be32_to_cpu(__raw_readl(addr));
 }
@@ -74,7 +74,7 @@ EXPORT_SYMBOL(iowrite32be);
  * convert to CPU byte order. We write in "IO byte
  * order" (we also don't have IO barriers).
  */
-static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
+static inline void mmio_insb(const void __iomem *addr, u8 *dst, int count)
 {
 	while (--count >= 0) {
 		u8 data = __raw_readb(addr);
@@ -83,7 +83,7 @@ static inline void mmio_insb(void __iomem *addr, u8 *dst, int
count)
 	}
 }
 
-static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
+static inline void mmio_insw(const void __iomem *addr, u16 *dst, int count)
 {
 	while (--count >= 0) {
 		u16 data = __raw_readw(addr);
@@ -92,7 +92,7 @@ static inline void mmio_insw(void __iomem *addr, u16 *dst, int
count)
 	}
 }
 
-static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
+static inline void mmio_insl(const void __iomem *addr, u32 *dst, int count)
 {
 	while (--count >= 0) {
 		u32 data = __raw_readl(addr);
@@ -125,19 +125,19 @@ static inline void mmio_outsl(void __iomem *addr, const
u32 *src, int count)
 	}
 }
 
-void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	mmio_insb(addr, dst, count);
 }
 EXPORT_SYMBOL(ioread8_rep);
 
-void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	mmio_insw(addr, dst, count);
 }
 EXPORT_SYMBOL(ioread16_rep);
 
-void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	mmio_insl(addr, dst, count);
 }
diff --git a/drivers/sh/clk/cpg.c b/drivers/sh/clk/cpg.c
index a5cacfe24a42..fd72d9088bdc 100644
--- a/drivers/sh/clk/cpg.c
+++ b/drivers/sh/clk/cpg.c
@@ -40,7 +40,7 @@ static int sh_clk_mstp_enable(struct clk *clk)
 {
 	sh_clk_write(sh_clk_read(clk) & ~(1 << clk->enable_bit), clk);
 	if (clk->status_reg) {
-		unsigned int (*read)(void __iomem *addr);
+		unsigned int (*read)(const void __iomem *addr);
 		int i;
 		void __iomem *mapped_status = (phys_addr_t)clk->status_reg -
 			(phys_addr_t)clk->enable_reg + clk->mapped_reg;
diff --git a/include/asm-generic/iomap.h b/include/asm-generic/iomap.h
index 9d28a5e82f73..649224664969 100644
--- a/include/asm-generic/iomap.h
+++ b/include/asm-generic/iomap.h
@@ -26,14 +26,14 @@
  * in the low address range. Architectures for which this is not
  * true can't use this generic implementation.
  */
-extern unsigned int ioread8(void __iomem *);
-extern unsigned int ioread16(void __iomem *);
-extern unsigned int ioread16be(void __iomem *);
-extern unsigned int ioread32(void __iomem *);
-extern unsigned int ioread32be(void __iomem *);
+extern unsigned int ioread8(const void __iomem *);
+extern unsigned int ioread16(const void __iomem *);
+extern unsigned int ioread16be(const void __iomem *);
+extern unsigned int ioread32(const void __iomem *);
+extern unsigned int ioread32be(const void __iomem *);
 #ifdef CONFIG_64BIT
-extern u64 ioread64(void __iomem *);
-extern u64 ioread64be(void __iomem *);
+extern u64 ioread64(const void __iomem *);
+extern u64 ioread64be(const void __iomem *);
 #endif
 
 #ifdef readq
@@ -41,10 +41,10 @@ extern u64 ioread64be(void __iomem *);
 #define ioread64_hi_lo ioread64_hi_lo
 #define ioread64be_lo_hi ioread64be_lo_hi
 #define ioread64be_hi_lo ioread64be_hi_lo
-extern u64 ioread64_lo_hi(void __iomem *addr);
-extern u64 ioread64_hi_lo(void __iomem *addr);
-extern u64 ioread64be_lo_hi(void __iomem *addr);
-extern u64 ioread64be_hi_lo(void __iomem *addr);
+extern u64 ioread64_lo_hi(const void __iomem *addr);
+extern u64 ioread64_hi_lo(const void __iomem *addr);
+extern u64 ioread64be_lo_hi(const void __iomem *addr);
+extern u64 ioread64be_hi_lo(const void __iomem *addr);
 #endif
 
 extern void iowrite8(u8, void __iomem *);
@@ -79,9 +79,9 @@ extern void iowrite64be_hi_lo(u64 val, void __iomem *addr);
  * memory across multiple ports, use "memcpy_toio()"
  * and friends.
  */
-extern void ioread8_rep(void __iomem *port, void *buf, unsigned long count);
-extern void ioread16_rep(void __iomem *port, void *buf, unsigned long count);
-extern void ioread32_rep(void __iomem *port, void *buf, unsigned long count);
+extern void ioread8_rep(const void __iomem *port, void *buf, unsigned long
count);
+extern void ioread16_rep(const void __iomem *port, void *buf, unsigned long
count);
+extern void ioread32_rep(const void __iomem *port, void *buf, unsigned long
count);
 
 extern void iowrite8_rep(void __iomem *port, const void *buf, unsigned long
count);
 extern void iowrite16_rep(void __iomem *port, const void *buf, unsigned long
count);
diff --git a/include/linux/io-64-nonatomic-hi-lo.h
b/include/linux/io-64-nonatomic-hi-lo.h
index ae21b72cce85..f32522bb3aa5 100644
--- a/include/linux/io-64-nonatomic-hi-lo.h
+++ b/include/linux/io-64-nonatomic-hi-lo.h
@@ -57,7 +57,7 @@ static inline void hi_lo_writeq_relaxed(__u64 val, volatile
void __iomem *addr)
 
 #ifndef ioread64_hi_lo
 #define ioread64_hi_lo ioread64_hi_lo
-static inline u64 ioread64_hi_lo(void __iomem *addr)
+static inline u64 ioread64_hi_lo(const void __iomem *addr)
 {
 	u32 low, high;
 
@@ -79,7 +79,7 @@ static inline void iowrite64_hi_lo(u64 val, void __iomem
*addr)
 
 #ifndef ioread64be_hi_lo
 #define ioread64be_hi_lo ioread64be_hi_lo
-static inline u64 ioread64be_hi_lo(void __iomem *addr)
+static inline u64 ioread64be_hi_lo(const void __iomem *addr)
 {
 	u32 low, high;
 
diff --git a/include/linux/io-64-nonatomic-lo-hi.h
b/include/linux/io-64-nonatomic-lo-hi.h
index faaa842dbdb9..448a21435dba 100644
--- a/include/linux/io-64-nonatomic-lo-hi.h
+++ b/include/linux/io-64-nonatomic-lo-hi.h
@@ -57,7 +57,7 @@ static inline void lo_hi_writeq_relaxed(__u64 val, volatile
void __iomem *addr)
 
 #ifndef ioread64_lo_hi
 #define ioread64_lo_hi ioread64_lo_hi
-static inline u64 ioread64_lo_hi(void __iomem *addr)
+static inline u64 ioread64_lo_hi(const void __iomem *addr)
 {
 	u32 low, high;
 
@@ -79,7 +79,7 @@ static inline void iowrite64_lo_hi(u64 val, void __iomem
*addr)
 
 #ifndef ioread64be_lo_hi
 #define ioread64be_lo_hi ioread64be_lo_hi
-static inline u64 ioread64be_lo_hi(void __iomem *addr)
+static inline u64 ioread64be_lo_hi(const void __iomem *addr)
 {
 	u32 low, high;
 
diff --git a/lib/iomap.c b/lib/iomap.c
index e909ab71e995..fbaa3e8f19d6 100644
--- a/lib/iomap.c
+++ b/lib/iomap.c
@@ -70,27 +70,27 @@ static void bad_io_access(unsigned long port, const char
*access)
 #define mmio_read64be(addr) swab64(readq(addr))
 #endif
 
-unsigned int ioread8(void __iomem *addr)
+unsigned int ioread8(const void __iomem *addr)
 {
 	IO_COND(addr, return inb(port), return readb(addr));
 	return 0xff;
 }
-unsigned int ioread16(void __iomem *addr)
+unsigned int ioread16(const void __iomem *addr)
 {
 	IO_COND(addr, return inw(port), return readw(addr));
 	return 0xffff;
 }
-unsigned int ioread16be(void __iomem *addr)
+unsigned int ioread16be(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read16be(port), return mmio_read16be(addr));
 	return 0xffff;
 }
-unsigned int ioread32(void __iomem *addr)
+unsigned int ioread32(const void __iomem *addr)
 {
 	IO_COND(addr, return inl(port), return readl(addr));
 	return 0xffffffff;
 }
-unsigned int ioread32be(void __iomem *addr)
+unsigned int ioread32be(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read32be(port), return mmio_read32be(addr));
 	return 0xffffffff;
@@ -142,26 +142,26 @@ static u64 pio_read64be_hi_lo(unsigned long port)
 	return lo | (hi << 32);
 }
 
-u64 ioread64_lo_hi(void __iomem *addr)
+u64 ioread64_lo_hi(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read64_lo_hi(port), return readq(addr));
 	return 0xffffffffffffffffULL;
 }
 
-u64 ioread64_hi_lo(void __iomem *addr)
+u64 ioread64_hi_lo(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read64_hi_lo(port), return readq(addr));
 	return 0xffffffffffffffffULL;
 }
 
-u64 ioread64be_lo_hi(void __iomem *addr)
+u64 ioread64be_lo_hi(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read64be_lo_hi(port),
 		return mmio_read64be(addr));
 	return 0xffffffffffffffffULL;
 }
 
-u64 ioread64be_hi_lo(void __iomem *addr)
+u64 ioread64be_hi_lo(const void __iomem *addr)
 {
 	IO_COND(addr, return pio_read64be_hi_lo(port),
 		return mmio_read64be(addr));
@@ -275,7 +275,7 @@ EXPORT_SYMBOL(iowrite64be_hi_lo);
  * order" (we also don't have IO barriers).
  */
 #ifndef mmio_insb
-static inline void mmio_insb(void __iomem *addr, u8 *dst, int count)
+static inline void mmio_insb(const void __iomem *addr, u8 *dst, int count)
 {
 	while (--count >= 0) {
 		u8 data = __raw_readb(addr);
@@ -283,7 +283,7 @@ static inline void mmio_insb(void __iomem *addr, u8 *dst,
int count)
 		dst++;
 	}
 }
-static inline void mmio_insw(void __iomem *addr, u16 *dst, int count)
+static inline void mmio_insw(const void __iomem *addr, u16 *dst, int count)
 {
 	while (--count >= 0) {
 		u16 data = __raw_readw(addr);
@@ -291,7 +291,7 @@ static inline void mmio_insw(void __iomem *addr, u16 *dst,
int count)
 		dst++;
 	}
 }
-static inline void mmio_insl(void __iomem *addr, u32 *dst, int count)
+static inline void mmio_insl(const void __iomem *addr, u32 *dst, int count)
 {
 	while (--count >= 0) {
 		u32 data = __raw_readl(addr);
@@ -325,15 +325,15 @@ static inline void mmio_outsl(void __iomem *addr, const
u32 *src, int count)
 }
 #endif
 
-void ioread8_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread8_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	IO_COND(addr, insb(port,dst,count), mmio_insb(addr, dst, count));
 }
-void ioread16_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread16_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	IO_COND(addr, insw(port,dst,count), mmio_insw(addr, dst, count));
 }
-void ioread32_rep(void __iomem *addr, void *dst, unsigned long count)
+void ioread32_rep(const void __iomem *addr, void *dst, unsigned long count)
 {
 	IO_COND(addr, insl(port,dst,count), mmio_insl(addr, dst, count));
 }
-- 
2.17.1

Krzysztof Kozlowski

2020-Jul-09 07:28 UTC

head link

[PATCH v3 2/4] rtl818x: Constify ioreadX() iomem argument (as in generic implementation)

The ioreadX() helpers have inconsistent interface.  On some architectures
void *__iomem address argument is a pointer to const, on some not.

Implementations of ioreadX() do not modify the memory under the address
so they can be converted to a "const" version for const-safety and
consistency among architectures.

Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
Acked-by: Kalle Valo <kvalo at codeaurora.org>
---
 drivers/net/wireless/realtek/rtl818x/rtl8180/rtl8180.h | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtl818x/rtl8180/rtl8180.h
b/drivers/net/wireless/realtek/rtl818x/rtl8180/rtl8180.h
index 7948a2da195a..2ff00800d45b 100644
--- a/drivers/net/wireless/realtek/rtl818x/rtl8180/rtl8180.h
+++ b/drivers/net/wireless/realtek/rtl818x/rtl8180/rtl8180.h
@@ -150,17 +150,17 @@ void rtl8180_write_phy(struct ieee80211_hw *dev, u8 addr,
u32 data);
 void rtl8180_set_anaparam(struct rtl8180_priv *priv, u32 anaparam);
 void rtl8180_set_anaparam2(struct rtl8180_priv *priv, u32 anaparam2);
 
-static inline u8 rtl818x_ioread8(struct rtl8180_priv *priv, u8 __iomem *addr)
+static inline u8 rtl818x_ioread8(struct rtl8180_priv *priv, const u8 __iomem
*addr)
 {
 	return ioread8(addr);
 }
 
-static inline u16 rtl818x_ioread16(struct rtl8180_priv *priv, __le16 __iomem
*addr)
+static inline u16 rtl818x_ioread16(struct rtl8180_priv *priv, const __le16
__iomem *addr)
 {
 	return ioread16(addr);
 }
 
-static inline u32 rtl818x_ioread32(struct rtl8180_priv *priv, __le32 __iomem
*addr)
+static inline u32 rtl818x_ioread32(struct rtl8180_priv *priv, const __le32
__iomem *addr)
 {
 	return ioread32(addr);
 }
-- 
2.17.1

Krzysztof Kozlowski

2020-Jul-09 07:28 UTC

head link

[PATCH v3 3/4] ntb: intel: Constify ioreadX() iomem argument (as in generic implementation)

The ioreadX() helpers have inconsistent interface.  On some architectures
void *__iomem address argument is a pointer to const, on some not.

Implementations of ioreadX() do not modify the memory under the address
so they can be converted to a "const" version for const-safety and
consistency among architectures.

Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
Acked-by: Dave Jiang <dave.jiang at intel.com>
---
 drivers/ntb/hw/intel/ntb_hw_gen1.c  | 2 +-
 drivers/ntb/hw/intel/ntb_hw_gen3.h  | 2 +-
 drivers/ntb/hw/intel/ntb_hw_intel.h | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/ntb/hw/intel/ntb_hw_gen1.c
b/drivers/ntb/hw/intel/ntb_hw_gen1.c
index 423f9b8fbbcf..3185efeab487 100644
--- a/drivers/ntb/hw/intel/ntb_hw_gen1.c
+++ b/drivers/ntb/hw/intel/ntb_hw_gen1.c
@@ -1205,7 +1205,7 @@ int intel_ntb_peer_spad_write(struct ntb_dev *ntb, int
pidx, int sidx,
 			       ndev->peer_reg->spad);
 }
 
-static u64 xeon_db_ioread(void __iomem *mmio)
+static u64 xeon_db_ioread(const void __iomem *mmio)
 {
 	return (u64)ioread16(mmio);
 }
diff --git a/drivers/ntb/hw/intel/ntb_hw_gen3.h
b/drivers/ntb/hw/intel/ntb_hw_gen3.h
index 2bc5d8356045..dea93989942d 100644
--- a/drivers/ntb/hw/intel/ntb_hw_gen3.h
+++ b/drivers/ntb/hw/intel/ntb_hw_gen3.h
@@ -91,7 +91,7 @@
 #define GEN3_DB_TOTAL_SHIFT		33
 #define GEN3_SPAD_COUNT			16
 
-static inline u64 gen3_db_ioread(void __iomem *mmio)
+static inline u64 gen3_db_ioread(const void __iomem *mmio)
 {
 	return ioread64(mmio);
 }
diff --git a/drivers/ntb/hw/intel/ntb_hw_intel.h
b/drivers/ntb/hw/intel/ntb_hw_intel.h
index d61fcd91714b..05e2335c9596 100644
--- a/drivers/ntb/hw/intel/ntb_hw_intel.h
+++ b/drivers/ntb/hw/intel/ntb_hw_intel.h
@@ -103,7 +103,7 @@ struct intel_ntb_dev;
 struct intel_ntb_reg {
 	int (*poll_link)(struct intel_ntb_dev *ndev);
 	int (*link_is_up)(struct intel_ntb_dev *ndev);
-	u64 (*db_ioread)(void __iomem *mmio);
+	u64 (*db_ioread)(const void __iomem *mmio);
 	void (*db_iowrite)(u64 db_bits, void __iomem *mmio);
 	unsigned long			ntb_ctl;
 	resource_size_t			db_size;
-- 
2.17.1

Krzysztof Kozlowski

2020-Jul-09 07:28 UTC

head link

[PATCH v3 4/4] virtio: pci: Constify ioreadX() iomem argument (as in generic implementation)

The ioreadX() helpers have inconsistent interface.  On some architectures
void *__iomem address argument is a pointer to const, on some not.

Implementations of ioreadX() do not modify the memory under the address
so they can be converted to a "const" version for const-safety and
consistency among architectures.

Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
---
 drivers/virtio/virtio_pci_modern.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/virtio/virtio_pci_modern.c
b/drivers/virtio/virtio_pci_modern.c
index db93cedd262f..90eff165a719 100644
--- a/drivers/virtio/virtio_pci_modern.c
+++ b/drivers/virtio/virtio_pci_modern.c
@@ -27,16 +27,16 @@
  * method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses
  * for 16-bit fields and 8-bit accesses for 8-bit fields.
  */
-static inline u8 vp_ioread8(u8 __iomem *addr)
+static inline u8 vp_ioread8(const u8 __iomem *addr)
 {
 	return ioread8(addr);
 }
-static inline u16 vp_ioread16 (__le16 __iomem *addr)
+static inline u16 vp_ioread16 (const __le16 __iomem *addr)
 {
 	return ioread16(addr);
 }
 
-static inline u32 vp_ioread32(__le32 __iomem *addr)
+static inline u32 vp_ioread32(const __le32 __iomem *addr)
 {
 	return ioread32(addr);
 }
-- 
2.17.1

Krzysztof Kozlowski

2020-Jul-09 07:32 UTC

head link

[PATCH v3 1/4] iomap: Constify ioreadX() iomem argument (as in generic implementation)

On Thu, Jul 09, 2020 at 09:28:34AM +0200, Krzysztof Kozlowski
wrote:> The ioreadX() and ioreadX_rep() helpers have inconsistent interface.  On
> some architectures void *__iomem address argument is a pointer to const,
> on some not.
> 
> Implementations of ioreadX() do not modify the memory under the address
> so they can be converted to a "const" version for const-safety
and
> consistency among architectures.
> 
> Suggested-by: Geert Uytterhoeven <geert at linux-m68k.org>
> Signed-off-by: Krzysztof Kozlowski <krzk at kernel.org>
> Reviewed-by: Geert Uytterhoeven <geert+renesas at glider.be>
> Reviewed-by: Arnd Bergmann <arnd at arndb.de>
I forgot to put here one more Ack, for PowerPC:
Acked-by: Michael Ellerman <mpe at ellerman.id.au> (powerpc)

https://lore.kernel.org/lkml/87ftedj0zz.fsf at mpe.ellerman.id.au/

Best regards,
Krzysztof

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[PATCH v3 2/4] rtl818x: Constify ioreadX() iomem argument (as in generic implementation)

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