From f58576666ccdcfb9cf7cae8669dffe1eed844f88 Mon Sep 17 00:00:00 2001 From: Jonathan Corbet Date: Fri, 27 Jan 2017 16:17:52 -0700 Subject: [PATCH] x86/mm: Improve documentation for low-level device I/O functions Add kerneldoc comments for memcpy_{to,from}io() and memset_io(). The existing documentation for ioremap() was distant from the definition, causing kernel-doc to miss it; move it appropriately. Signed-off-by: Jonathan Corbet Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Link: http://lkml.kernel.org/r/20170127161752.0b95e95b@lwn.net Signed-off-by: Ingo Molnar --- arch/x86/include/asm/io.h | 46 +++++++++++++++++++++++++++++---------- 1 file changed, 35 insertions(+), 11 deletions(-) diff --git a/arch/x86/include/asm/io.h b/arch/x86/include/asm/io.h index d34bd370074b..7afb0e2f07f4 100644 --- a/arch/x86/include/asm/io.h +++ b/arch/x86/include/asm/io.h @@ -164,6 +164,17 @@ static inline unsigned int isa_virt_to_bus(volatile void *address) #define virt_to_bus virt_to_phys #define bus_to_virt phys_to_virt +/* + * The default ioremap() behavior is non-cached; if you need something + * else, you probably want one of the following. + */ +extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size); +extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size); +#define ioremap_uc ioremap_uc + +extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size); +extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, unsigned long prot_val); + /** * ioremap - map bus memory into CPU space * @offset: bus address of the memory @@ -178,17 +189,6 @@ static inline unsigned int isa_virt_to_bus(volatile void *address) * If the area you are trying to map is a PCI BAR you should have a * look at pci_iomap(). */ -extern void __iomem *ioremap_nocache(resource_size_t offset, unsigned long size); -extern void __iomem *ioremap_uc(resource_size_t offset, unsigned long size); -#define ioremap_uc ioremap_uc - -extern void __iomem *ioremap_cache(resource_size_t offset, unsigned long size); -extern void __iomem *ioremap_prot(resource_size_t offset, unsigned long size, - unsigned long prot_val); - -/* - * The default ioremap() behavior is non-cached: - */ static inline void __iomem *ioremap(resource_size_t offset, unsigned long size) { return ioremap_nocache(offset, size); @@ -207,18 +207,42 @@ extern void set_iounmap_nonlazy(void); */ #define xlate_dev_kmem_ptr(p) p +/** + * memset_io Set a range of I/O memory to a constant value + * @addr: The beginning of the I/O-memory range to set + * @val: The value to set the memory to + * @count: The number of bytes to set + * + * Set a range of I/O memory to a given value. + */ static inline void memset_io(volatile void __iomem *addr, unsigned char val, size_t count) { memset((void __force *)addr, val, count); } +/** + * memcpy_fromio Copy a block of data from I/O memory + * @dst: The (RAM) destination for the copy + * @src: The (I/O memory) source for the data + * @count: The number of bytes to copy + * + * Copy a block of data from I/O memory. + */ static inline void memcpy_fromio(void *dst, const volatile void __iomem *src, size_t count) { memcpy(dst, (const void __force *)src, count); } +/** + * memcpy_toio Copy a block of data into I/O memory + * @dst: The (I/O memory) destination for the copy + * @src: The (RAM) source for the data + * @count: The number of bytes to copy + * + * Copy a block of data to I/O memory. + */ static inline void memcpy_toio(volatile void __iomem *dst, const void *src, size_t count) { -- 2.20.1