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1// SPDX-License-Identifier: GPL-2.02/*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 the5 * 640k-1MB IO memory area on PC's6 *7 * (C) Copyright 1995 1996 Linus Torvalds8 */9#include <linux/vmalloc.h>10#include <linux/mm.h>11#include <linux/io.h>12#include <linux/export.h>13#include <linux/ioremap.h>14 15void __iomem *generic_ioremap_prot(phys_addr_t phys_addr, size_t size,16 pgprot_t prot)17{18 unsigned long offset, vaddr;19 phys_addr_t last_addr;20 struct vm_struct *area;21 22 /* An early platform driver might end up here */23 if (WARN_ON_ONCE(!slab_is_available()))24 return NULL;25 26 /* Disallow wrap-around or zero size */27 last_addr = phys_addr + size - 1;28 if (!size || last_addr < phys_addr)29 return NULL;30 31 /* Page-align mappings */32 offset = phys_addr & (~PAGE_MASK);33 phys_addr -= offset;34 size = PAGE_ALIGN(size + offset);35 36 area = __get_vm_area_caller(size, VM_IOREMAP, IOREMAP_START,37 IOREMAP_END, __builtin_return_address(0));38 if (!area)39 return NULL;40 vaddr = (unsigned long)area->addr;41 area->phys_addr = phys_addr;42 43 if (ioremap_page_range(vaddr, vaddr + size, phys_addr, prot)) {44 free_vm_area(area);45 return NULL;46 }47 48 return (void __iomem *)(vaddr + offset);49}50 51#ifndef ioremap_prot52void __iomem *ioremap_prot(phys_addr_t phys_addr, size_t size,53 unsigned long prot)54{55 return generic_ioremap_prot(phys_addr, size, __pgprot(prot));56}57EXPORT_SYMBOL(ioremap_prot);58#endif59 60void generic_iounmap(volatile void __iomem *addr)61{62 void *vaddr = (void *)((unsigned long)addr & PAGE_MASK);63 64 if (is_ioremap_addr(vaddr))65 vunmap(vaddr);66}67 68#ifndef iounmap69void iounmap(volatile void __iomem *addr)70{71 generic_iounmap(addr);72}73EXPORT_SYMBOL(iounmap);74#endif75