With all subsystems and drivers either declaring their dependence on HAS_IOPORT or fencing I/O port specific code sections we can finally make inb()/outb() and friends compile-time dependent on HAS_IOPORT as suggested by Linus in the linked mail. The main benefit of this is that on platforms such as s390 which have no meaningful way of implementing inb()/outb() their use without the proper HAS_IOPORT dependency will result in easy to catch and fix compile-time errors instead of compiling code that can never work.
Link: https://lore.kernel.org/lkml/CAHk-=wg80je=k7madf4e7wrrnp37e3qh6y10svhdc7o8sz_...@mail.gmail.com/ Co-developed-by: Arnd Bergmann <a...@kernel.org> Signed-off-by: Arnd Bergmann <a...@kernel.org> Signed-off-by: Niklas Schnelle <schne...@linux.ibm.com> --- include/asm-generic/io.h | 60 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) diff --git a/include/asm-generic/io.h b/include/asm-generic/io.h index 80de699bf6af4b7b77f582c0469c43e978f67a43..1027be6a62bcbcd5f6797e0fa42035208d0ca79f 100644 --- a/include/asm-generic/io.h +++ b/include/asm-generic/io.h @@ -540,6 +540,7 @@ static inline void writesq(volatile void __iomem *addr, const void *buffer, #if !defined(inb) && !defined(_inb) #define _inb _inb +#ifdef CONFIG_HAS_IOPORT static inline u8 _inb(unsigned long addr) { u8 val; @@ -549,10 +550,15 @@ static inline u8 _inb(unsigned long addr) __io_par(val); return val; } +#else +u8 _inb(unsigned long addr) + __compiletime_error("inb()) requires CONFIG_HAS_IOPORT"); +#endif #endif #if !defined(inw) && !defined(_inw) #define _inw _inw +#ifdef CONFIG_HAS_IOPORT static inline u16 _inw(unsigned long addr) { u16 val; @@ -562,10 +568,15 @@ static inline u16 _inw(unsigned long addr) __io_par(val); return val; } +#else +u16 _inw(unsigned long addr) + __compiletime_error("inw() requires CONFIG_HAS_IOPORT"); +#endif #endif #if !defined(inl) && !defined(_inl) #define _inl _inl +#ifdef CONFIG_HAS_IOPORT static inline u32 _inl(unsigned long addr) { u32 val; @@ -575,36 +586,55 @@ static inline u32 _inl(unsigned long addr) __io_par(val); return val; } +#else +u32 _inl(unsigned long addr) + __compiletime_error("inl() requires CONFIG_HAS_IOPORT"); +#endif #endif #if !defined(outb) && !defined(_outb) #define _outb _outb +#ifdef CONFIG_HAS_IOPORT static inline void _outb(u8 value, unsigned long addr) { __io_pbw(); __raw_writeb(value, PCI_IOBASE + addr); __io_paw(); } +#else +void _outb(u8 value, unsigned long addr) + __compiletime_error("outb() requires CONFIG_HAS_IOPORT"); +#endif #endif #if !defined(outw) && !defined(_outw) #define _outw _outw +#ifdef CONFIG_HAS_IOPORT static inline void _outw(u16 value, unsigned long addr) { __io_pbw(); __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); __io_paw(); } +#else +void _outw(u16 value, unsigned long addr) + __compiletime_error("outw() requires CONFIG_HAS_IOPORT"); +#endif #endif #if !defined(outl) && !defined(_outl) #define _outl _outl +#ifdef CONFIG_HAS_IOPORT static inline void _outl(u32 value, unsigned long addr) { __io_pbw(); __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); __io_paw(); } +#else +void _outl(u32 value, unsigned long addr) + __compiletime_error("outl() requires CONFIG_HAS_IOPORT"); +#endif #endif #include <linux/logic_pio.h> @@ -688,53 +718,83 @@ static inline void outl_p(u32 value, unsigned long addr) #ifndef insb #define insb insb +#ifdef CONFIG_HAS_IOPORT static inline void insb(unsigned long addr, void *buffer, unsigned int count) { readsb(PCI_IOBASE + addr, buffer, count); } +#else +void insb(unsigned long addr, void *buffer, unsigned int count) + __compiletime_error("insb() requires HAS_IOPORT"); +#endif #endif #ifndef insw #define insw insw +#ifdef CONFIG_HAS_IOPORT static inline void insw(unsigned long addr, void *buffer, unsigned int count) { readsw(PCI_IOBASE + addr, buffer, count); } +#else +void insw(unsigned long addr, void *buffer, unsigned int count) + __compiletime_error("insw() requires HAS_IOPORT"); +#endif #endif #ifndef insl #define insl insl +#ifdef CONFIG_HAS_IOPORT static inline void insl(unsigned long addr, void *buffer, unsigned int count) { readsl(PCI_IOBASE + addr, buffer, count); } +#else +void insl(unsigned long addr, void *buffer, unsigned int count) + __compiletime_error("insl() requires HAS_IOPORT"); +#endif #endif #ifndef outsb #define outsb outsb +#ifdef CONFIG_HAS_IOPORT static inline void outsb(unsigned long addr, const void *buffer, unsigned int count) { writesb(PCI_IOBASE + addr, buffer, count); } +#else +void outsb(unsigned long addr, const void *buffer, unsigned int count) + __compiletime_error("outsb() requires HAS_IOPORT"); +#endif #endif #ifndef outsw #define outsw outsw +#ifdef CONFIG_HAS_IOPORT static inline void outsw(unsigned long addr, const void *buffer, unsigned int count) { writesw(PCI_IOBASE + addr, buffer, count); } +#else +void outsw(unsigned long addr, const void *buffer, unsigned int count) + __compiletime_error("outsw() requires HAS_IOPORT"); +#endif #endif #ifndef outsl #define outsl outsl +#ifdef CONFIG_HAS_IOPORT static inline void outsl(unsigned long addr, const void *buffer, unsigned int count) { writesl(PCI_IOBASE + addr, buffer, count); } +#else +void outsl(unsigned long addr, const void *buffer, unsigned int count) + __compiletime_error("outsl() requires HAS_IOPORT"); +#endif #endif #ifndef insb_p -- 2.43.0