Commit f5857666 authored by Jonathan Corbet's avatar Jonathan Corbet Committed by Ingo Molnar
Browse files

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: default avatarJonathan Corbet <corbet@lwn.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20170127161752.0b95e95b@lwn.net


Signed-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent 1b1bc42c

arch/x86/include/asm/io.h

+35 −11
Original line number Diff line number Diff line
@@ -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)

{

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