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1// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.02/******************************************************************************3 *4 * Module Name: osunixmap - Unix OSL for file mappings5 *6 * Copyright (C) 2000 - 2023, Intel Corp.7 *8 *****************************************************************************/9 10#include "acpidump.h"11#include <unistd.h>12#include <sys/mman.h>13#ifdef _free_BSD14#include <sys/param.h>15#endif16 17#define _COMPONENT ACPI_OS_SERVICES18ACPI_MODULE_NAME("osunixmap")19 20#ifndef O_BINARY21#define O_BINARY 022#endif23#if defined(_dragon_fly) || defined(_free_BSD) || defined(_QNX)24#define MMAP_FLAGS MAP_SHARED25#else26#define MMAP_FLAGS MAP_PRIVATE27#endif28#define SYSTEM_MEMORY "/dev/mem"29/*******************************************************************************30 *31 * FUNCTION: acpi_os_get_page_size32 *33 * PARAMETERS: None34 *35 * RETURN: Page size of the platform.36 *37 * DESCRIPTION: Obtain page size of the platform.38 *39 ******************************************************************************/40static acpi_size acpi_os_get_page_size(void)41{42 43#ifdef PAGE_SIZE44 return PAGE_SIZE;45#else46 return sysconf(_SC_PAGESIZE);47#endif48}49 50/******************************************************************************51 *52 * FUNCTION: acpi_os_map_memory53 *54 * PARAMETERS: where - Physical address of memory to be mapped55 * length - How much memory to map56 *57 * RETURN: Pointer to mapped memory. Null on error.58 *59 * DESCRIPTION: Map physical memory into local address space.60 *61 *****************************************************************************/62 63void *acpi_os_map_memory(acpi_physical_address where, acpi_size length)64{65 u8 *mapped_memory;66 acpi_physical_address offset;67 acpi_size page_size;68 int fd;69 70 fd = open(SYSTEM_MEMORY, O_RDONLY | O_BINARY);71 if (fd < 0) {72 fprintf(stderr, "Cannot open %s\n", SYSTEM_MEMORY);73 return (NULL);74 }75 76 /* Align the offset to use mmap */77 78 page_size = acpi_os_get_page_size();79 offset = where % page_size;80 81 /* Map the table header to get the length of the full table */82 83 mapped_memory = mmap(NULL, (length + offset), PROT_READ, MMAP_FLAGS,84 fd, (where - offset));85 if (mapped_memory == MAP_FAILED) {86 fprintf(stderr, "Cannot map %s\n", SYSTEM_MEMORY);87 close(fd);88 return (NULL);89 }90 91 close(fd);92 return (ACPI_CAST8(mapped_memory + offset));93}94 95/******************************************************************************96 *97 * FUNCTION: acpi_os_unmap_memory98 *99 * PARAMETERS: where - Logical address of memory to be unmapped100 * length - How much memory to unmap101 *102 * RETURN: None.103 *104 * DESCRIPTION: Delete a previously created mapping. Where and Length must105 * correspond to a previous mapping exactly.106 *107 *****************************************************************************/108 109void acpi_os_unmap_memory(void *where, acpi_size length)110{111 acpi_physical_address offset;112 acpi_size page_size;113 114 page_size = acpi_os_get_page_size();115 offset = ACPI_TO_INTEGER(where) % page_size;116 munmap((u8 *)where - offset, (length + offset));117}118