[mirror_ubuntu-jammy-kernel.git] / mm / ioremap.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Re-map IO memory to kernel address space so that we can access it.
 * This is needed for high PCI addresses that aren't mapped in the
 * 640k-1MB IO memory area on PC's
 *
 * (C) Copyright 1995 1996 Linus Torvalds
 */
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/export.h>

void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
{
	unsigned long offset, vaddr;
	phys_addr_t last_addr;
	struct vm_struct *area;

	/* Disallow wrap-around or zero size */
	last_addr = addr + size - 1;
	if (!size || last_addr < addr)
		return NULL;

	/* Page-align mappings */
	offset = addr & (~PAGE_MASK);
	addr -= offset;
	size = PAGE_ALIGN(size + offset);

	area = get_vm_area_caller(size, VM_IOREMAP,
			__builtin_return_address(0));
	if (!area)
		return NULL;
	vaddr = (unsigned long)area->addr;

	if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
		free_vm_area(area);
		return NULL;
	}

	return (void __iomem *)(vaddr + offset);
}
EXPORT_SYMBOL(ioremap_prot);

void iounmap(volatile void __iomem *addr)
{
	vunmap((void *)((unsigned long)addr & PAGE_MASK));
}
EXPORT_SYMBOL(iounmap);
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
74588d8b HS	2	/*
	3	* Re-map IO memory to kernel address space so that we can access it.
	4	* This is needed for high PCI addresses that aren't mapped in the
	5	* 640k-1MB IO memory area on PC's
	6	*
	7	* (C) Copyright 1995 1996 Linus Torvalds
	8	*/
74588d8b HS	9	#include <linux/vmalloc.h>
74588d8b HS	10	#include <linux/mm.h>
53fa6645	11	#include <linux/io.h>
8bc3bcc9	12	#include <linux/export.h>
74588d8b	13
80b0ca98 CH	14	void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
	15	{
	16	unsigned long offset, vaddr;
	17	phys_addr_t last_addr;
	18	struct vm_struct *area;
	19
	20	/* Disallow wrap-around or zero size */
	21	last_addr = addr + size - 1;
	22	if (!size \|\| last_addr < addr)
	23	return NULL;
	24
	25	/* Page-align mappings */
	26	offset = addr & (~PAGE_MASK);
	27	addr -= offset;
	28	size = PAGE_ALIGN(size + offset);
	29
	30	area = get_vm_area_caller(size, VM_IOREMAP,
	31	__builtin_return_address(0));
	32	if (!area)
	33	return NULL;
	34	vaddr = (unsigned long)area->addr;
	35
	36	if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
	37	free_vm_area(area);
	38	return NULL;
	39	}
	40
	41	return (void __iomem *)(vaddr + offset);
	42	}
	43	EXPORT_SYMBOL(ioremap_prot);
	44
	45	void iounmap(volatile void __iomem *addr)
	46	{
	47	vunmap((void *)((unsigned long)addr & PAGE_MASK));
	48	}
	49	EXPORT_SYMBOL(iounmap);