[mirror_ubuntu-jammy-kernel.git] / lib / 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>
#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_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 HS	14	#include <asm/cacheflush.h>
	15	#include <asm/pgtable.h>
	16
0ddab1d2	17	#ifdef CONFIG_HAVE_ARCH_HUGE_VMAP
c2febafc	18	static int __read_mostly ioremap_p4d_capable;
6b637835 TK	19	static int __read_mostly ioremap_pud_capable;
	20	static int __read_mostly ioremap_pmd_capable;
	21	static int __read_mostly ioremap_huge_disabled;
0ddab1d2 TK	22
	23	static int __init set_nohugeiomap(char *str)
	24	{
	25	ioremap_huge_disabled = 1;
	26	return 0;
	27	}
	28	early_param("nohugeiomap", set_nohugeiomap);
	29
	30	void __init ioremap_huge_init(void)
	31	{
	32	if (!ioremap_huge_disabled) {
0f472d04 AK	33	if (arch_ioremap_p4d_supported())
0f472d04 AK	34	ioremap_p4d_capable = 1;
0ddab1d2 TK	35	if (arch_ioremap_pud_supported())
	36	ioremap_pud_capable = 1;
	37	if (arch_ioremap_pmd_supported())
	38	ioremap_pmd_capable = 1;
	39	}
	40	}
	41
c2febafc KS	42	static inline int ioremap_p4d_enabled(void)
	43	{
	44	return ioremap_p4d_capable;
	45	}
	46
0ddab1d2 TK	47	static inline int ioremap_pud_enabled(void)
	48	{
	49	return ioremap_pud_capable;
	50	}
	51
	52	static inline int ioremap_pmd_enabled(void)
	53	{
	54	return ioremap_pmd_capable;
	55	}
	56
	57	#else /* !CONFIG_HAVE_ARCH_HUGE_VMAP */
c2febafc	58	static inline int ioremap_p4d_enabled(void) { return 0; }
0ddab1d2 TK	59	static inline int ioremap_pud_enabled(void) { return 0; }
	60	static inline int ioremap_pmd_enabled(void) { return 0; }
	61	#endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */
	62
74588d8b	63	static int ioremap_pte_range(pmd_t *pmd, unsigned long addr,
6c0c7d2b JR	64	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	65	pgtbl_mod_mask *mask)
74588d8b HS	66	{
74588d8b HS	67	pte_t *pte;
ffa71f33	68	u64 pfn;
74588d8b HS	69
74588d8b HS	70	pfn = phys_addr >> PAGE_SHIFT;
6c0c7d2b	71	pte = pte_alloc_kernel_track(pmd, addr, mask);
74588d8b HS	72	if (!pte)
	73	return -ENOMEM;
	74	do {
	75	BUG_ON(!pte_none(*pte));
	76	set_pte_at(&init_mm, addr, pte, pfn_pte(pfn, prot));
	77	pfn++;
	78	} while (pte++, addr += PAGE_SIZE, addr != end);
6c0c7d2b	79	*mask \|= PGTBL_PTE_MODIFIED;
74588d8b HS	80	return 0;
	81	}
	82
d239865a WD	83	static int ioremap_try_huge_pmd(pmd_t *pmd, unsigned long addr,
	84	unsigned long end, phys_addr_t phys_addr,
	85	pgprot_t prot)
	86	{
	87	if (!ioremap_pmd_enabled())
	88	return 0;
	89
	90	if ((end - addr) != PMD_SIZE)
	91	return 0;
	92
6b95ab42 AK	93	if (!IS_ALIGNED(addr, PMD_SIZE))
	94	return 0;
	95
d239865a WD	96	if (!IS_ALIGNED(phys_addr, PMD_SIZE))
	97	return 0;
	98
	99	if (pmd_present(*pmd) && !pmd_free_pte_page(pmd, addr))
	100	return 0;
	101
	102	return pmd_set_huge(pmd, phys_addr, prot);
	103	}
	104
74588d8b	105	static inline int ioremap_pmd_range(pud_t *pud, unsigned long addr,
6c0c7d2b JR	106	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	107	pgtbl_mod_mask *mask)
74588d8b HS	108	{
	109	pmd_t *pmd;
	110	unsigned long next;
	111
6c0c7d2b	112	pmd = pmd_alloc_track(&init_mm, pud, addr, mask);
74588d8b HS	113	if (!pmd)
	114	return -ENOMEM;
	115	do {
	116	next = pmd_addr_end(addr, end);
e61ce6ad	117
6c0c7d2b JR	118	if (ioremap_try_huge_pmd(pmd, addr, next, phys_addr, prot)) {
6c0c7d2b JR	119	*mask \|= PGTBL_PMD_MODIFIED;
d239865a	120	continue;
6c0c7d2b	121	}
e61ce6ad	122
6c0c7d2b	123	if (ioremap_pte_range(pmd, addr, next, phys_addr, prot, mask))
74588d8b	124	return -ENOMEM;
36ddc5a7	125	} while (pmd++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b HS	126	return 0;
	127	}
	128
d239865a WD	129	static int ioremap_try_huge_pud(pud_t *pud, unsigned long addr,
	130	unsigned long end, phys_addr_t phys_addr,
	131	pgprot_t prot)
	132	{
	133	if (!ioremap_pud_enabled())
	134	return 0;
	135
	136	if ((end - addr) != PUD_SIZE)
	137	return 0;
	138
6b95ab42 AK	139	if (!IS_ALIGNED(addr, PUD_SIZE))
	140	return 0;
	141
d239865a WD	142	if (!IS_ALIGNED(phys_addr, PUD_SIZE))
	143	return 0;
	144
	145	if (pud_present(*pud) && !pud_free_pmd_page(pud, addr))
	146	return 0;
	147
	148	return pud_set_huge(pud, phys_addr, prot);
	149	}
	150
c2febafc	151	static inline int ioremap_pud_range(p4d_t *p4d, unsigned long addr,
6c0c7d2b JR	152	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	153	pgtbl_mod_mask *mask)
74588d8b HS	154	{
	155	pud_t *pud;
	156	unsigned long next;
	157
6c0c7d2b	158	pud = pud_alloc_track(&init_mm, p4d, addr, mask);
74588d8b HS	159	if (!pud)
	160	return -ENOMEM;
	161	do {
	162	next = pud_addr_end(addr, end);
e61ce6ad	163
6c0c7d2b JR	164	if (ioremap_try_huge_pud(pud, addr, next, phys_addr, prot)) {
6c0c7d2b JR	165	*mask \|= PGTBL_PUD_MODIFIED;
d239865a	166	continue;
6c0c7d2b	167	}
e61ce6ad	168
6c0c7d2b	169	if (ioremap_pmd_range(pud, addr, next, phys_addr, prot, mask))
74588d8b	170	return -ENOMEM;
36ddc5a7	171	} while (pud++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b HS	172	return 0;
	173	}
	174
8e2d4340 WD	175	static int ioremap_try_huge_p4d(p4d_t *p4d, unsigned long addr,
	176	unsigned long end, phys_addr_t phys_addr,
	177	pgprot_t prot)
	178	{
	179	if (!ioremap_p4d_enabled())
	180	return 0;
	181
	182	if ((end - addr) != P4D_SIZE)
	183	return 0;
	184
6b95ab42 AK	185	if (!IS_ALIGNED(addr, P4D_SIZE))
	186	return 0;
	187
8e2d4340 WD	188	if (!IS_ALIGNED(phys_addr, P4D_SIZE))
	189	return 0;
	190
	191	if (p4d_present(*p4d) && !p4d_free_pud_page(p4d, addr))
	192	return 0;
	193
	194	return p4d_set_huge(p4d, phys_addr, prot);
	195	}
	196
c2febafc	197	static inline int ioremap_p4d_range(pgd_t *pgd, unsigned long addr,
6c0c7d2b JR	198	unsigned long end, phys_addr_t phys_addr, pgprot_t prot,
6c0c7d2b JR	199	pgtbl_mod_mask *mask)
c2febafc KS	200	{
	201	p4d_t *p4d;
	202	unsigned long next;
	203
6c0c7d2b	204	p4d = p4d_alloc_track(&init_mm, pgd, addr, mask);
c2febafc KS	205	if (!p4d)
	206	return -ENOMEM;
	207	do {
	208	next = p4d_addr_end(addr, end);
	209
6c0c7d2b JR	210	if (ioremap_try_huge_p4d(p4d, addr, next, phys_addr, prot)) {
6c0c7d2b JR	211	*mask \|= PGTBL_P4D_MODIFIED;
8e2d4340	212	continue;
6c0c7d2b	213	}
c2febafc	214
6c0c7d2b	215	if (ioremap_pud_range(p4d, addr, next, phys_addr, prot, mask))
c2febafc	216	return -ENOMEM;
36ddc5a7	217	} while (p4d++, phys_addr += (next - addr), addr = next, addr != end);
c2febafc KS	218	return 0;
	219	}
	220
74588d8b	221	int ioremap_page_range(unsigned long addr,
ffa71f33	222	unsigned long end, phys_addr_t phys_addr, pgprot_t prot)
74588d8b HS	223	{
	224	pgd_t *pgd;
	225	unsigned long start;
	226	unsigned long next;
	227	int err;
6c0c7d2b	228	pgtbl_mod_mask mask = 0;
74588d8b	229
b39ab98e	230	might_sleep();
74588d8b HS	231	BUG_ON(addr >= end);
74588d8b HS	232
74588d8b	233	start = addr;
74588d8b HS	234	pgd = pgd_offset_k(addr);
	235	do {
	236	next = pgd_addr_end(addr, end);
6c0c7d2b JR	237	err = ioremap_p4d_range(pgd, addr, next, phys_addr, prot,
6c0c7d2b JR	238	&mask);
74588d8b HS	239	if (err)
74588d8b HS	240	break;
36ddc5a7	241	} while (pgd++, phys_addr += (next - addr), addr = next, addr != end);
74588d8b	242
db71daab	243	flush_cache_vmap(start, end);
74588d8b	244
6c0c7d2b JR	245	if (mask & ARCH_PAGE_TABLE_SYNC_MASK)
	246	arch_sync_kernel_mappings(start, end);
	247
74588d8b HS	248	return err;
74588d8b HS	249	}
80b0ca98 CH	250
	251	#ifdef CONFIG_GENERIC_IOREMAP
	252	void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot)
	253	{
	254	unsigned long offset, vaddr;
	255	phys_addr_t last_addr;
	256	struct vm_struct *area;
	257
	258	/* Disallow wrap-around or zero size */
	259	last_addr = addr + size - 1;
	260	if (!size \|\| last_addr < addr)
	261	return NULL;
	262
	263	/* Page-align mappings */
	264	offset = addr & (~PAGE_MASK);
	265	addr -= offset;
	266	size = PAGE_ALIGN(size + offset);
	267
	268	area = get_vm_area_caller(size, VM_IOREMAP,
	269	__builtin_return_address(0));
	270	if (!area)
	271	return NULL;
	272	vaddr = (unsigned long)area->addr;
	273
	274	if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) {
	275	free_vm_area(area);
	276	return NULL;
	277	}
	278
	279	return (void __iomem *)(vaddr + offset);
	280	}
	281	EXPORT_SYMBOL(ioremap_prot);
	282
	283	void iounmap(volatile void __iomem *addr)
	284	{
	285	vunmap((void *)((unsigned long)addr & PAGE_MASK));
	286	}
	287	EXPORT_SYMBOL(iounmap);
	288	#endif /* CONFIG_GENERIC_IOREMAP */