// SPDX-License-Identifier: GPL-2.0-only /* * Based on arch/arm/mm/ioremap.c * * (C) Copyright 1995 1996 Linus Torvalds * Hacked for ARM by Phil Blundell <philb@gnu.org> * Hacked to allow all architectures to build, and various cleanups * by Russell King * Copyright (C) 2012 ARM Ltd. */ #include <linux/export.h> #include <linux/mm.h> #include <linux/vmalloc.h> #include <linux/io.h> #include <asm/fixmap.h> #include <asm/tlbflush.h> static void __iomem *__ioremap_caller(phys_addr_t phys_addr, size_t size, pgprot_t prot, void *caller) { unsigned long last_addr; unsigned long offset = phys_addr & ~PAGE_MASK; int err; unsigned long addr; struct vm_struct *area; /* * Page align the mapping address and size, taking account of any * offset. */ phys_addr &= PAGE_MASK; size = PAGE_ALIGN(size + offset); /* * Don't allow wraparound, zero size or outside PHYS_MASK. */ last_addr = phys_addr + size - 1; if (!size || last_addr < phys_addr || (last_addr & ~PHYS_MASK)) return NULL; /* * Don't allow RAM to be mapped. */ if (WARN_ON(pfn_is_map_memory(__phys_to_pfn(phys_addr)))) return NULL; area = get_vm_area_caller(size, VM_IOREMAP, caller); if (!area) return NULL; addr = (unsigned long)area->addr; area->phys_addr = phys_addr; err = ioremap_page_range(addr, addr + size, phys_addr, prot); if (err) { vunmap((void *)addr); return NULL; } return (void __iomem *)(offset + addr); } void __iomem *__ioremap(phys_addr_t phys_addr, size_t size, pgprot_t prot) { return __ioremap_caller(phys_addr, size, prot, __builtin_return_address(0)); } EXPORT_SYMBOL(__ioremap); void iounmap(volatile void __iomem *io_addr) { unsigned long addr = (unsigned long)io_addr & PAGE_MASK; /* * We could get an address outside vmalloc range in case * of ioremap_cache() reusing a RAM mapping. */ if (is_vmalloc_addr((void *)addr)) vunmap((void *)addr); } EXPORT_SYMBOL(iounmap); void __iomem *ioremap_cache(phys_addr_t phys_addr, size_t size) { /* For normal memory we already have a cacheable mapping. */ if (pfn_is_map_memory(__phys_to_pfn(phys_addr))) return (void __iomem *)__phys_to_virt(phys_addr); return __ioremap_caller(phys_addr, size, __pgprot(PROT_NORMAL), __builtin_return_address(0)); } EXPORT_SYMBOL(ioremap_cache); /* * Must be called after early_fixmap_init */ void __init early_ioremap_init(void) { early_ioremap_setup(); } bool arch_memremap_can_ram_remap(resource_size_t offset, size_t size, unsigned long flags) { unsigned long pfn = PHYS_PFN(offset); return pfn_is_map_memory(pfn); }