[mirror_ubuntu-bionic-kernel.git] / lib / ioremap.c

/*
 * 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/sched.h>
#include <linux/io.h>
#include <linux/module.h>
#include <asm/cacheflush.h>
#include <asm/pgtable.h>

static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
	pte_t *pte;
	u64 pfn;

	pfn = phys_addr >> PAGE_SHIFT;
	pte = pte_alloc_kernel(pmd, addr);
	if (!pte)
		return -ENOMEM;
	do {
		BUG_ON(!pte_none(*pte));
		set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
		pfn++;
	} while (pte++, addr += PAGE_SIZE, addr != end);
	return 0;
}

static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
	pmd_t *pmd;
	unsigned long next;

	phys_addr -= addr;
	pmd = pmd_alloc(&init_mm, pud, addr);
	if (!pmd)
		return -ENOMEM;
	do {
		next = pmd_addr_end(addr, end);
		if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
			return -ENOMEM;
	} while (pmd++, addr = next, addr != end);
	return 0;
}

static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
	pud_t *pud;
	unsigned long next;

	phys_addr -= addr;
	pud = pud_alloc(&init_mm, pgd, addr);
	if (!pud)
		return -ENOMEM;
	do {
		next = pud_addr_end(addr, end);
		if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
			return -ENOMEM;
	} while (pud++, addr = next, addr != end);
	return 0;
}

int ioremap_page_range(unsigned long addr,
		       unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
	pgd_t *pgd;
	unsigned long start;
	unsigned long next;
	int err;

	BUG_ON(addr >= end);

	start = addr;
	phys_addr -= addr;
	pgd = pgd_offset_k(addr);
	do {
		next = pgd_addr_end(addr, end);
		err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
		if (err)
			break;
	} while (pgd++, addr = next, addr != end);

	flush_cache_vmap(start, end);

	return err;
}
EXPORT_SYMBOL_GPL(ioremap_page_range);
Commit	Line	Data
74588d8b HS	1	/*
	2	* Re-map IO memory to kernel address space so that we can access it.
	3	* This is needed for high PCI addresses that aren't mapped in the
	4	* 640k-1MB IO memory area on PC's
	5	*
	6	* (C) Copyright 1995 1996 Linus Torvalds
	7	*/
74588d8b HS	8	#include <linux/vmalloc.h>
74588d8b HS	9	#include <linux/mm.h>
e8edc6e0	10	#include <linux/sched.h>
53fa6645	11	#include <linux/io.h>
81e88fdc	12	#include <linux/module.h>
74588d8b HS	13	#include <asm/cacheflush.h>
	14	#include <asm/pgtable.h>
	15
	16	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
ffa71f33	17	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	18	{
74588d8b HS	19	pte_t *pte;
ffa71f33	20	u64 pfn;
74588d8b HS	21
	22	pfn = phys_addr >> PAGE_SHIFT;
	23	pte = pte_alloc_kernel(pmd, addr);
	24	if (!pte)
	25	return -ENOMEM;
	26	do {
	27	BUG_ON(!pte_none(*pte));
	28	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
	29	pfn++;
	30	} while (pte++, addr += PAGE_SIZE, addr != end);
	31	return 0;
	32	}
	33
	34	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
ffa71f33	35	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	36	{
	37	pmd_t *pmd;
	38	unsigned long next;
	39
	40	phys_addr -= addr;
	41	pmd = pmd_alloc(&init_mm, pud, addr);
	42	if (!pmd)
	43	return -ENOMEM;
	44	do {
	45	next = pmd_addr_end(addr, end);
	46	if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
	47	return -ENOMEM;
	48	} while (pmd++, addr = next, addr != end);
	49	return 0;
	50	}
	51
	52	static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
ffa71f33	53	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	54	{
	55	pud_t *pud;
	56	unsigned long next;
	57
	58	phys_addr -= addr;
	59	pud = pud_alloc(&init_mm, pgd, addr);
	60	if (!pud)
	61	return -ENOMEM;
	62	do {
	63	next = pud_addr_end(addr, end);
	64	if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
	65	return -ENOMEM;
	66	} while (pud++, addr = next, addr != end);
	67	return 0;
	68	}
	69
	70	int ioremap_page_range(unsigned long addr,
ffa71f33	71	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	72	{
	73	pgd_t *pgd;
	74	unsigned long start;
	75	unsigned long next;
	76	int err;
	77
	78	BUG_ON(addr >= end);
	79
74588d8b HS	80	start = addr;
	81	phys_addr -= addr;
	82	pgd = pgd_offset_k(addr);
	83	do {
	84	next = pgd_addr_end(addr, end);
	85	err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
	86	if (err)
	87	break;
	88	} while (pgd++, addr = next, addr != end);
	89
db71daab	90	flush_cache_vmap(start, end);
74588d8b HS	91
	92	return err;
	93	}
81e88fdc	94	EXPORT_SYMBOL_GPL(ioremap_page_range);