[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/sched.h>
#include <linux/io.h>
#include <linux/export.h>
#include <asm/cacheflush.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_p4d_supported())
			ioremap_p4d_capable = 1;
		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,
		pgtbl_mod_mask *mask)
{
	pte_t *pte;
	u64 pfn;

	pfn = phys_addr >> PAGE_SHIFT;
	pte = pte_alloc_kernel_track(pmd, addr, mask);
	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);
	*mask |= PGTBL_PTE_MODIFIED;
	return 0;
}

static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
				unsigned long end, phys_addr_t phys_addr,
				pgprot_t prot)
{
	if (!ioremap_pmd_enabled())
		return 0;

	if ((end - addr) != PMD_SIZE)
		return 0;

	if (!IS_ALIGNED(addr, PMD_SIZE))
		return 0;

	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
		return 0;

	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
		return 0;

	return pmd_set_huge(pmd, phys_addr, prot);
}

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

	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
	if (!pmd)
		return -ENOMEM;
	do {
		next = pmd_addr_end(addr, end);

		if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
			*mask |= PGTBL_PMD_MODIFIED;
			continue;
		}

		if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
			return -ENOMEM;
	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
	return 0;
}

static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
				unsigned long end, phys_addr_t phys_addr,
				pgprot_t prot)
{
	if (!ioremap_pud_enabled())
		return 0;

	if ((end - addr) != PUD_SIZE)
		return 0;

	if (!IS_ALIGNED(addr, PUD_SIZE))
		return 0;

	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
		return 0;

	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
		return 0;

	return pud_set_huge(pud, phys_addr, prot);
}

static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
		unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
		pgtbl_mod_mask *mask)
{
	pud_t *pud;
	unsigned long next;

	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
	if (!pud)
		return -ENOMEM;
	do {
		next = pud_addr_end(addr, end);

		if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
			*mask |= PGTBL_PUD_MODIFIED;
			continue;
		}

		if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
			return -ENOMEM;
	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
	return 0;
}

static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
				unsigned long end, phys_addr_t phys_addr,
				pgprot_t prot)
{
	if (!ioremap_p4d_enabled())
		return 0;

	if ((end - addr) != P4D_SIZE)
		return 0;

	if (!IS_ALIGNED(addr, P4D_SIZE))
		return 0;

	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
		return 0;

	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
		return 0;

	return p4d_set_huge(p4d, phys_addr, prot);
}

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

	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
	if (!p4d)
		return -ENOMEM;
	do {
		next = p4d_addr_end(addr, end);

		if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
			*mask |= PGTBL_P4D_MODIFIED;
			continue;
		}

		if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
			return -ENOMEM;
	} while (p4d++, phys_addr += (next - addr), 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;
	pgtbl_mod_mask mask = 0;

	might_sleep();
	BUG_ON(addr >= end);

	start = addr;
	pgd = pgd_offset_k(addr);
	do {
		next = pgd_addr_end(addr, end);
		err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
					&mask);
		if (err)
			break;
	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);

	flush_cache_vmap(start, end);

	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
		arch_sync_kernel_mappings(start, end);

	return err;
}

#ifdef CONFIG_GENERIC_IOREMAP
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);
#endif /* CONFIG_GENERIC_IOREMAP */
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>
e8edc6e0	11	#include <linux/sched.h>
53fa6645	12	#include <linux/io.h>
8bc3bcc9	13	#include <linux/export.h>
74588d8b	14	#include <asm/cacheflush.h>
74588d8b	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) {
0f472d04 AK	32	if (arch_ioremap_p4d_supported())
0f472d04 AK	33	ioremap_p4d_capable = 1;
0ddab1d2 TK	34	if (arch_ioremap_pud_supported())
	35	ioremap_pud_capable = 1;
	36	if (arch_ioremap_pmd_supported())
	37	ioremap_pmd_capable = 1;
	38	}
	39	}
	40
c2febafc KS	41	static inline int ioremap_p4d_enabled(void)
	42	{
	43	return ioremap_p4d_capable;
	44	}
	45
0ddab1d2 TK	46	static inline int ioremap_pud_enabled(void)
	47	{
	48	return ioremap_pud_capable;
	49	}
	50
	51	static inline int ioremap_pmd_enabled(void)
	52	{
	53	return ioremap_pmd_capable;
	54	}
	55
	56	#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
c2febafc	57	static inline int ioremap_p4d_enabled(void) { return 0; }
0ddab1d2 TK	58	static inline int ioremap_pud_enabled(void) { return 0; }
	59	static inline int ioremap_pmd_enabled(void) { return 0; }
	60	#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
	61
74588d8b	62	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
6c0c7d2b JR	63	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	64	pgtbl_mod_mask *mask)
74588d8b HS	65	{
74588d8b HS	66	pte_t *pte;
ffa71f33	67	u64 pfn;
74588d8b HS	68
74588d8b HS	69	pfn = phys_addr >> PAGE_SHIFT;
6c0c7d2b	70	pte = pte_alloc_kernel_track(pmd, addr, mask);
74588d8b HS	71	if (!pte)
	72	return -ENOMEM;
	73	do {
	74	BUG_ON(!pte_none(*pte));
	75	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
	76	pfn++;
	77	} while (pte++, addr += PAGE_SIZE, addr != end);
6c0c7d2b	78	*mask \|= PGTBL_PTE_MODIFIED;
74588d8b HS	79	return 0;
	80	}
	81
d239865a WD	82	static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
	83	unsigned long end, phys_addr_t phys_addr,
	84	pgprot_t prot)
	85	{
	86	if (!ioremap_pmd_enabled())
	87	return 0;
	88
	89	if ((end - addr) != PMD_SIZE)
	90	return 0;
	91
6b95ab42 AK	92	if (!IS_ALIGNED(addr, PMD_SIZE))
	93	return 0;
	94
d239865a WD	95	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
	96	return 0;
	97
	98	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
	99	return 0;
	100
	101	return pmd_set_huge(pmd, phys_addr, prot);
	102	}
	103
74588d8b	104	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
6c0c7d2b JR	105	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	106	pgtbl_mod_mask *mask)
74588d8b HS	107	{
	108	pmd_t *pmd;
	109	unsigned long next;
	110
6c0c7d2b	111	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
74588d8b HS	112	if (!pmd)
	113	return -ENOMEM;
	114	do {
	115	next = pmd_addr_end(addr, end);
e61ce6ad	116
6c0c7d2b JR	117	if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
6c0c7d2b JR	118	*mask \|= PGTBL_PMD_MODIFIED;
d239865a	119	continue;
6c0c7d2b	120	}
e61ce6ad	121
6c0c7d2b	122	if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
74588d8b	123	return -ENOMEM;
36ddc5a7	124	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b HS	125	return 0;
	126	}
	127
d239865a WD	128	static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
	129	unsigned long end, phys_addr_t phys_addr,
	130	pgprot_t prot)
	131	{
	132	if (!ioremap_pud_enabled())
	133	return 0;
	134
	135	if ((end - addr) != PUD_SIZE)
	136	return 0;
	137
6b95ab42 AK	138	if (!IS_ALIGNED(addr, PUD_SIZE))
	139	return 0;
	140
d239865a WD	141	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
	142	return 0;
	143
	144	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
	145	return 0;
	146
	147	return pud_set_huge(pud, phys_addr, prot);
	148	}
	149
c2febafc	150	static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
6c0c7d2b JR	151	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	152	pgtbl_mod_mask *mask)
74588d8b HS	153	{
	154	pud_t *pud;
	155	unsigned long next;
	156
6c0c7d2b	157	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
74588d8b HS	158	if (!pud)
	159	return -ENOMEM;
	160	do {
	161	next = pud_addr_end(addr, end);
e61ce6ad	162
6c0c7d2b JR	163	if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
6c0c7d2b JR	164	*mask \|= PGTBL_PUD_MODIFIED;
d239865a	165	continue;
6c0c7d2b	166	}
e61ce6ad	167
6c0c7d2b	168	if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
74588d8b	169	return -ENOMEM;
36ddc5a7	170	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b HS	171	return 0;
	172	}
	173
8e2d4340 WD	174	static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
	175	unsigned long end, phys_addr_t phys_addr,
	176	pgprot_t prot)
	177	{
	178	if (!ioremap_p4d_enabled())
	179	return 0;
	180
	181	if ((end - addr) != P4D_SIZE)
	182	return 0;
	183
6b95ab42 AK	184	if (!IS_ALIGNED(addr, P4D_SIZE))
	185	return 0;
	186
8e2d4340 WD	187	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
	188	return 0;
	189
	190	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
	191	return 0;
	192
	193	return p4d_set_huge(p4d, phys_addr, prot);
	194	}
	195
c2febafc	196	static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
6c0c7d2b JR	197	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	198	pgtbl_mod_mask *mask)
c2febafc KS	199	{
	200	p4d_t *p4d;
	201	unsigned long next;
	202
6c0c7d2b	203	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
c2febafc KS	204	if (!p4d)
	205	return -ENOMEM;
	206	do {
	207	next = p4d_addr_end(addr, end);
	208
6c0c7d2b JR	209	if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
6c0c7d2b JR	210	*mask \|= PGTBL_P4D_MODIFIED;
8e2d4340	211	continue;
6c0c7d2b	212	}
c2febafc	213
6c0c7d2b	214	if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
c2febafc	215	return -ENOMEM;
36ddc5a7	216	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
c2febafc KS	217	return 0;
	218	}
	219
74588d8b	220	int ioremap_page_range(unsigned long addr,
ffa71f33	221	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	222	{
	223	pgd_t *pgd;
	224	unsigned long start;
	225	unsigned long next;
	226	int err;
6c0c7d2b	227	pgtbl_mod_mask mask = 0;
74588d8b	228
b39ab98e	229	might_sleep();
74588d8b HS	230	BUG_ON(addr >= end);
74588d8b HS	231
74588d8b	232	start = addr;
74588d8b HS	233	pgd = pgd_offset_k(addr);
	234	do {
	235	next = pgd_addr_end(addr, end);
6c0c7d2b JR	236	err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
6c0c7d2b JR	237	&mask);
74588d8b HS	238	if (err)
74588d8b HS	239	break;
36ddc5a7	240	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b	241
db71daab	242	flush_cache_vmap(start, end);
74588d8b	243
6c0c7d2b JR	244	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
	245	arch_sync_kernel_mappings(start, end);
	246
74588d8b HS	247	return err;
74588d8b HS	248	}
80b0ca98 CH	249
	250	#ifdef CONFIG_GENERIC_IOREMAP
	251	void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
	252	{
	253	unsigned long offset, vaddr;
	254	phys_addr_t last_addr;
	255	struct vm_struct *area;
	256
	257	/* Disallow wrap-around or zero size */
	258	last_addr = addr + size - 1;
	259	if (!size \|\| last_addr < addr)
	260	return NULL;
	261
	262	/* Page-align mappings */
	263	offset = addr & (~PAGE_MASK);
	264	addr -= offset;
	265	size = PAGE_ALIGN(size + offset);
	266
	267	area = get_vm_area_caller(size, VM_IOREMAP,
	268	__builtin_return_address(0));
	269	if (!area)
	270	return NULL;
	271	vaddr = (unsigned long)area->addr;
	272
	273	if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
	274	free_vm_area(area);
	275	return NULL;
	276	}
	277
	278	return (void __iomem *)(vaddr + offset);
	279	}
	280	EXPORT_SYMBOL(ioremap_prot);
	281
	282	void iounmap(volatile void __iomem *addr)
	283	{
	284	vunmap((void *)((unsigned long)addr & PAGE_MASK));
	285	}
	286	EXPORT_SYMBOL(iounmap);
	287	#endif /* CONFIG_GENERIC_IOREMAP */