projects / linux.git / blame
| 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> |
| 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 | |
| 2a681cfa JR |
16 | #include "pgalloc-track.h" |
| 17 | ||
| 0ddab1d2 | 18 | #ifdef CONFIG_HAVE_ARCH_HUGE_VMAP |
| 86d0c164 | 19 | static unsigned int __ro_after_init iomap_max_page_shift = BITS_PER_LONG - 1; |
| 0ddab1d2 TK |
20 | |
| 21 | static int __init set_nohugeiomap(char *str) | |
| 22 | { | |
| 86d0c164 | 23 | iomap_max_page_shift = PAGE_SHIFT; |
| 0ddab1d2 TK |
24 | return 0; |
| 25 | } | |
| 26 | early_param("nohugeiomap", set_nohugeiomap); | |
| bbc180a5 | 27 | #else /* CONFIG_HAVE_ARCH_HUGE_VMAP */ |
| 86d0c164 | 28 | static const unsigned int iomap_max_page_shift = PAGE_SHIFT; |
| 0ddab1d2 TK |
29 | #endif /* CONFIG_HAVE_ARCH_HUGE_VMAP */ |
| 30 | ||
| 95f0ddf0 NP |
31 | int ioremap_page_range(unsigned long addr, |
| 32 | unsigned long end, phys_addr_t phys_addr, pgprot_t prot) | |
| 33 | { | |
| bbc180a5 | 34 | return vmap_range(addr, end, phys_addr, prot, iomap_max_page_shift); |
| 95f0ddf0 NP |
35 | } |
| 36 | ||
| 80b0ca98 CH |
37 | #ifdef CONFIG_GENERIC_IOREMAP |
| 38 | void __iomem *ioremap_prot(phys_addr_t addr, size_t size, unsigned long prot) | |
| 39 | { | |
| 40 | unsigned long offset, vaddr; | |
| 41 | phys_addr_t last_addr; | |
| 42 | struct vm_struct *area; | |
| 43 | ||
| 44 | /* Disallow wrap-around or zero size */ | |
| 45 | last_addr = addr + size - 1; | |
| 46 | if (!size || last_addr < addr) | |
| 47 | return NULL; | |
| 48 | ||
| 49 | /* Page-align mappings */ | |
| 50 | offset = addr & (~PAGE_MASK); | |
| 51 | addr -= offset; | |
| 52 | size = PAGE_ALIGN(size + offset); | |
| 53 | ||
| 54 | area = get_vm_area_caller(size, VM_IOREMAP, | |
| 55 | __builtin_return_address(0)); | |
| 56 | if (!area) | |
| 57 | return NULL; | |
| 58 | vaddr = (unsigned long)area->addr; | |
| 59 | ||
| 60 | if (ioremap_page_range(vaddr, vaddr + size, addr, __pgprot(prot))) { | |
| 61 | free_vm_area(area); | |
| 62 | return NULL; | |
| 63 | } | |
| 64 | ||
| 65 | return (void __iomem *)(vaddr + offset); | |
| 66 | } | |
| 67 | EXPORT_SYMBOL(ioremap_prot); | |
| 68 | ||
| 69 | void iounmap(volatile void __iomem *addr) | |
| 70 | { | |
| 71 | vunmap((void *)((unsigned long)addr & PAGE_MASK)); | |
| 72 | } | |
| 73 | EXPORT_SYMBOL(iounmap); | |
| 74 | #endif /* CONFIG_GENERIC_IOREMAP */ |