[linux-2.6-block.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/export.h>
#include <asm/cacheflush.h>
#include <asm/pgtable.h>

#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
static int __read_mostly ioremap_pud_capable;
static int __read_mostly ioremap_pmd_capable;
static int __read_mostly ioremap_huge_disabled;

static int __init set_nohugeiomap(char *str)
{
	ioremap_huge_disabled = 1;
	return 0;
}
early_param("nohugeiomap", set_nohugeiomap);

void __init ioremap_huge_init(void)
{
	if (!ioremap_huge_disabled) {
		if (arch_ioremap_pud_supported())
			ioremap_pud_capable = 1;
		if (arch_ioremap_pmd_supported())
			ioremap_pmd_capable = 1;
	}
}

static inline int ioremap_pud_enabled(void)
{
	return ioremap_pud_capable;
}

static inline int ioremap_pmd_enabled(void)
{
	return ioremap_pmd_capable;
}

#else	/* !CONFIG_HAVE_ARCH_HUGE_VMAP */
static inline int ioremap_pud_enabled(void) { return 0; }
static inline int ioremap_pmd_enabled(void) { return 0; }
#endif	/* CONFIG_HAVE_ARCH_HUGE_VMAP */

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_pmd_enabled() &&
		    ((next - addr) == PMD_SIZE) &&
		    IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {
			if (pmd_set_huge(pmd, phys_addr + addr, prot))
				continue;
		}

		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_pud_enabled() &&
		    ((next - addr) == PUD_SIZE) &&
		    IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {
			if (pud_set_huge(pud, phys_addr + addr, prot))
				continue;
		}

		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>
8bc3bcc9	12	#include <linux/export.h>
74588d8b HS	13	#include <asm/cacheflush.h>
	14	#include <asm/pgtable.h>
	15
0ddab1d2	16	#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
6b637835 TK	17	static int __read_mostly ioremap_pud_capable;
	18	static int __read_mostly ioremap_pmd_capable;
	19	static int __read_mostly ioremap_huge_disabled;
0ddab1d2 TK	20
	21	static int __init set_nohugeiomap(char *str)
	22	{
	23	ioremap_huge_disabled = 1;
	24	return 0;
	25	}
	26	early_param("nohugeiomap", set_nohugeiomap);
	27
	28	void __init ioremap_huge_init(void)
	29	{
	30	if (!ioremap_huge_disabled) {
	31	if (arch_ioremap_pud_supported())
	32	ioremap_pud_capable = 1;
	33	if (arch_ioremap_pmd_supported())
	34	ioremap_pmd_capable = 1;
	35	}
	36	}
	37
	38	static inline int ioremap_pud_enabled(void)
	39	{
	40	return ioremap_pud_capable;
	41	}
	42
	43	static inline int ioremap_pmd_enabled(void)
	44	{
	45	return ioremap_pmd_capable;
	46	}
	47
	48	#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
	49	static inline int ioremap_pud_enabled(void) { return 0; }
	50	static inline int ioremap_pmd_enabled(void) { return 0; }
	51	#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
	52
74588d8b	53	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
ffa71f33	54	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	55	{
74588d8b HS	56	pte_t *pte;
ffa71f33	57	u64 pfn;
74588d8b HS	58
	59	pfn = phys_addr >> PAGE_SHIFT;
	60	pte = pte_alloc_kernel(pmd, addr);
	61	if (!pte)
	62	return -ENOMEM;
	63	do {
	64	BUG_ON(!pte_none(*pte));
	65	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
	66	pfn++;
	67	} while (pte++, addr += PAGE_SIZE, addr != end);
	68	return 0;
	69	}
	70
	71	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
ffa71f33	72	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	73	{
	74	pmd_t *pmd;
	75	unsigned long next;
	76
	77	phys_addr -= addr;
	78	pmd = pmd_alloc(&init_mm, pud, addr);
	79	if (!pmd)
	80	return -ENOMEM;
	81	do {
	82	next = pmd_addr_end(addr, end);
e61ce6ad TK	83
	84	if (ioremap_pmd_enabled() &&
	85	((next - addr) == PMD_SIZE) &&
	86	IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {
	87	if (pmd_set_huge(pmd, phys_addr + addr, prot))
	88	continue;
	89	}
	90
74588d8b HS	91	if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
	92	return -ENOMEM;
	93	} while (pmd++, addr = next, addr != end);
	94	return 0;
	95	}
	96
	97	static inline int ioremap_pud_range(pgd_t *pgd, unsigned long addr,
ffa71f33	98	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	99	{
	100	pud_t *pud;
	101	unsigned long next;
	102
	103	phys_addr -= addr;
	104	pud = pud_alloc(&init_mm, pgd, addr);
	105	if (!pud)
	106	return -ENOMEM;
	107	do {
	108	next = pud_addr_end(addr, end);
e61ce6ad TK	109
	110	if (ioremap_pud_enabled() &&
	111	((next - addr) == PUD_SIZE) &&
	112	IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {
	113	if (pud_set_huge(pud, phys_addr + addr, prot))
	114	continue;
	115	}
	116
74588d8b HS	117	if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
	118	return -ENOMEM;
	119	} while (pud++, addr = next, addr != end);
	120	return 0;
	121	}
	122
	123	int ioremap_page_range(unsigned long addr,
ffa71f33	124	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	125	{
	126	pgd_t *pgd;
	127	unsigned long start;
	128	unsigned long next;
	129	int err;
	130
	131	BUG_ON(addr >= end);
	132
74588d8b HS	133	start = addr;
	134	phys_addr -= addr;
	135	pgd = pgd_offset_k(addr);
	136	do {
	137	next = pgd_addr_end(addr, end);
	138	err = ioremap_pud_range(pgd, addr, next, phys_addr+addr, prot);
	139	if (err)
	140	break;
	141	} while (pgd++, addr = next, addr != end);
	142
db71daab	143	flush_cache_vmap(start, end);
74588d8b HS	144
	145	return err;
	146	}
81e88fdc	147	EXPORT_SYMBOL_GPL(ioremap_page_range);