[mirror_ubuntu-artful-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/export.h>
#include <asm/cacheflush.h>
#include <asm/pgtable.h>

#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
static int __read_mostly ioremap_p4d_capable;
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_p4d_enabled(void)
{
	return ioremap_p4d_capable;
}

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_p4d_enabled(void) { return 0; }
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(p4d_t *p4d, 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, p4d, 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;
}

static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
		unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
{
	p4d_t *p4d;
	unsigned long next;

	phys_addr -= addr;
	p4d = p4d_alloc(&init_mm, pgd, addr);
	if (!p4d)
		return -ENOMEM;
	do {
		next = p4d_addr_end(addr, end);

		if (ioremap_p4d_enabled() &&
		    ((next - addr) == P4D_SIZE) &&
		    IS_ALIGNED(phys_addr + addr, P4D_SIZE)) {
			if (p4d_set_huge(p4d, phys_addr + addr, prot))
				continue;
		}

		if (ioremap_pud_range(p4d, addr, next, phys_addr + addr, prot))
			return -ENOMEM;
	} while (p4d++, 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_p4d_range(pgd, addr, next, phys_addr+addr, prot);
		if (err)
			break;
	} while (pgd++, addr = next, addr != end);

	flush_cache_vmap(start, end);

	return err;
}
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
c2febafc	17	static int __read_mostly ioremap_p4d_capable;
6b637835 TK	18	static int __read_mostly ioremap_pud_capable;
	19	static int __read_mostly ioremap_pmd_capable;
	20	static int __read_mostly ioremap_huge_disabled;
0ddab1d2 TK	21
	22	static int __init set_nohugeiomap(char *str)
	23	{
	24	ioremap_huge_disabled = 1;
	25	return 0;
	26	}
	27	early_param("nohugeiomap", set_nohugeiomap);
	28
	29	void __init ioremap_huge_init(void)
	30	{
	31	if (!ioremap_huge_disabled) {
	32	if (arch_ioremap_pud_supported())
	33	ioremap_pud_capable = 1;
	34	if (arch_ioremap_pmd_supported())
	35	ioremap_pmd_capable = 1;
	36	}
	37	}
	38
c2febafc KS	39	static inline int ioremap_p4d_enabled(void)
	40	{
	41	return ioremap_p4d_capable;
	42	}
	43
0ddab1d2 TK	44	static inline int ioremap_pud_enabled(void)
	45	{
	46	return ioremap_pud_capable;
	47	}
	48
	49	static inline int ioremap_pmd_enabled(void)
	50	{
	51	return ioremap_pmd_capable;
	52	}
	53
	54	#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
c2febafc	55	static inline int ioremap_p4d_enabled(void) { return 0; }
0ddab1d2 TK	56	static inline int ioremap_pud_enabled(void) { return 0; }
	57	static inline int ioremap_pmd_enabled(void) { return 0; }
	58	#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
	59
74588d8b	60	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
ffa71f33	61	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	62	{
74588d8b HS	63	pte_t *pte;
ffa71f33	64	u64 pfn;
74588d8b HS	65
	66	pfn = phys_addr >> PAGE_SHIFT;
	67	pte = pte_alloc_kernel(pmd, addr);
	68	if (!pte)
	69	return -ENOMEM;
	70	do {
	71	BUG_ON(!pte_none(*pte));
	72	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
	73	pfn++;
	74	} while (pte++, addr += PAGE_SIZE, addr != end);
	75	return 0;
	76	}
	77
	78	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
ffa71f33	79	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	80	{
	81	pmd_t *pmd;
	82	unsigned long next;
	83
	84	phys_addr -= addr;
	85	pmd = pmd_alloc(&init_mm, pud, addr);
	86	if (!pmd)
	87	return -ENOMEM;
	88	do {
	89	next = pmd_addr_end(addr, end);
e61ce6ad TK	90
	91	if (ioremap_pmd_enabled() &&
	92	((next - addr) == PMD_SIZE) &&
	93	IS_ALIGNED(phys_addr + addr, PMD_SIZE)) {
	94	if (pmd_set_huge(pmd, phys_addr + addr, prot))
	95	continue;
	96	}
	97
74588d8b HS	98	if (ioremap_pte_range(pmd, addr, next, phys_addr + addr, prot))
	99	return -ENOMEM;
	100	} while (pmd++, addr = next, addr != end);
	101	return 0;
	102	}
	103
c2febafc	104	static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
ffa71f33	105	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	106	{
	107	pud_t *pud;
	108	unsigned long next;
	109
	110	phys_addr -= addr;
c2febafc	111	pud = pud_alloc(&init_mm, p4d, addr);
74588d8b HS	112	if (!pud)
	113	return -ENOMEM;
	114	do {
	115	next = pud_addr_end(addr, end);
e61ce6ad TK	116
	117	if (ioremap_pud_enabled() &&
	118	((next - addr) == PUD_SIZE) &&
	119	IS_ALIGNED(phys_addr + addr, PUD_SIZE)) {
	120	if (pud_set_huge(pud, phys_addr + addr, prot))
	121	continue;
	122	}
	123
74588d8b HS	124	if (ioremap_pmd_range(pud, addr, next, phys_addr + addr, prot))
	125	return -ENOMEM;
	126	} while (pud++, addr = next, addr != end);
	127	return 0;
	128	}
	129
c2febafc KS	130	static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
	131	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
	132	{
	133	p4d_t *p4d;
	134	unsigned long next;
	135
	136	phys_addr -= addr;
	137	p4d = p4d_alloc(&init_mm, pgd, addr);
	138	if (!p4d)
	139	return -ENOMEM;
	140	do {
	141	next = p4d_addr_end(addr, end);
	142
	143	if (ioremap_p4d_enabled() &&
	144	((next - addr) == P4D_SIZE) &&
	145	IS_ALIGNED(phys_addr + addr, P4D_SIZE)) {
	146	if (p4d_set_huge(p4d, phys_addr + addr, prot))
	147	continue;
	148	}
	149
	150	if (ioremap_pud_range(p4d, addr, next, phys_addr + addr, prot))
	151	return -ENOMEM;
	152	} while (p4d++, addr = next, addr != end);
	153	return 0;
	154	}
	155
74588d8b	156	int ioremap_page_range(unsigned long addr,
ffa71f33	157	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	158	{
	159	pgd_t *pgd;
	160	unsigned long start;
	161	unsigned long next;
	162	int err;
	163
	164	BUG_ON(addr >= end);
	165
74588d8b HS	166	start = addr;
	167	phys_addr -= addr;
	168	pgd = pgd_offset_k(addr);
	169	do {
	170	next = pgd_addr_end(addr, end);
c2febafc	171	err = ioremap_p4d_range(pgd, addr, next, phys_addr+addr, prot);
74588d8b HS	172	if (err)
	173	break;
	174	} while (pgd++, addr = next, addr != end);
	175
db71daab	176	flush_cache_vmap(start, end);
74588d8b HS	177
	178	return err;
	179	}