Loop.cpp revision a19b250bd273455933ca3502cf2c2e0a803aff77
1a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat/* 2a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * Copyright (C) 2008 The Android Open Source Project 3a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * 4a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * Licensed under the Apache License, Version 2.0 (the "License"); 5a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * you may not use this file except in compliance with the License. 6a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * You may obtain a copy of the License at 7a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * 8a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * http://www.apache.org/licenses/LICENSE-2.0 9a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * 10a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * Unless required by applicable law or agreed to in writing, software 11a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * distributed under the License is distributed on an "AS IS" BASIS, 12a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * See the License for the specific language governing permissions and 14a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat * limitations under the License. 15a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat */ 16a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 17a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <stdio.h> 18a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <fcntl.h> 19a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <unistd.h> 20a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <errno.h> 21a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <string.h> 22a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 23a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#define LOG_TAG "Vold" 24a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 25a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include <cutils/log.h> 26a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 27a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat#include "Loop.h" 28a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 29a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::lookupActive(const char *loopFile, char *buffer, size_t len) { 30a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int i; 31a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int fd; 32a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat char filename[256]; 33a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 34a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat memset(buffer, 0, len); 35a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 36a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat for (i = 0; i < LOOP_MAX; i++) { 37a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat struct loop_info li; 38a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int rc; 39a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 40a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat sprintf(filename, "/dev/block/loop%d", i); 41a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 42a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if ((fd = open(filename, O_RDWR)) < 0) { 43a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to open %s (%s)", filename, strerror(errno)); 44a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 45a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 46a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 47a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat rc = ioctl(fd, LOOP_GET_STATUS, &li); 48a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 49a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (rc < 0 && errno == ENXIO) { 50a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat continue; 51a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat break; 52a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 53a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 54a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (rc < 0) { 55a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to get loop status for %s (%s)", filename, 56a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strerror(errno)); 57a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 58a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 59a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (!strncmp(li.lo_name, loopFile, LO_NAME_SIZE)) { 60a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat break; 61a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 62a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 63a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 64a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (i == LOOP_MAX) { 65a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat errno = ENOENT; 66a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 67a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 68a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strncpy(buffer, filename, len -1); 69a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return 0; 70a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 71a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 72a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::getNextAvailable(char *buffer, size_t len) { 73a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int i; 74a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int fd; 75a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat char filename[256]; 76a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 77a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat memset(buffer, 0, len); 78a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 79a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat for (i = 0; i < LOOP_MAX; i++) { 80a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat struct loop_info li; 81a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int rc; 82a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 83a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat sprintf(filename, "/dev/block/loop%d", i); 84a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 85a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if ((fd = open(filename, O_RDWR)) < 0) { 86a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to open %s (%s)", filename, strerror(errno)); 87a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 88a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 89a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 90a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat rc = ioctl(fd, LOOP_GET_STATUS, &li); 91a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 92a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (rc < 0 && errno == ENXIO) 93a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat break; 94a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 95a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (rc < 0) { 96a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to get loop status for %s (%s)", filename, 97a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strerror(errno)); 98a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 99a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 100a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 101a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 102a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (i == LOOP_MAX) { 103a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Exhausted all loop devices"); 104a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat errno = ENOSPC; 105a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 106a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 107a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strncpy(buffer, filename, len -1); 108a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return 0; 109a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 110a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 111a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::create(const char *loopDevice, const char *loopFile) { 112a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int fd; 113a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int file_fd; 114a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 115a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGD("Creating loop for file '%s' into loop device '%s'", loopFile, 116a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat loopDevice); 117a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if ((fd = open(loopDevice, O_RDWR)) < 0) { 118a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to open loop device %s (%s)", loopDevice, 119a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strerror(errno)); 120a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 121a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 122a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 123a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if ((file_fd = open(loopFile, O_RDWR)) < 0) { 124a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Unable to open %s (%s)", loopFile, strerror(errno)); 125a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 126a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 127a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 128a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 129a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (ioctl(fd, LOOP_SET_FD, file_fd) < 0) { 130a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Error setting up loopback interface (%s)", strerror(errno)); 131a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(file_fd); 132a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 133a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 134a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 135a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 136a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat struct loop_info li; 137a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 138a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat memset(&li, 0, sizeof(li)); 139a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat strncpy(li.lo_name, loopFile, LO_NAME_SIZE); 140a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 141a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (ioctl(fd, LOOP_SET_STATUS, &li) < 0) { 142a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Error setting loopback status (%s)", strerror(errno)); 143a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(file_fd); 144a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 145a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 146a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 147a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 148a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 149a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(file_fd); 150a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 151a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return 0; 152a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 153a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 154a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::destroyByDevice(const char *loopDevice) { 155a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int device_fd; 156a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 157a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat device_fd = open(loopDevice, O_RDONLY); 158a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (device_fd < 0) { 159a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Failed to open loop (%d)", errno); 160a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 161a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 162a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 163a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (ioctl(device_fd, LOOP_CLR_FD, 0) < 0) { 164a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Failed to destroy loop (%d)", errno); 165a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(device_fd); 166a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 167a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 168a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 169a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(device_fd); 170a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return 0; 171a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 172a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 173a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::destroyByFile(const char *loopFile) { 174a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat errno = ENOSYS; 175a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 176a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 177a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 178a19b250bd273455933ca3502cf2c2e0a803aff77San Mehatint Loop::createImageFile(const char *file, size_t sizeMb) { 179a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat int fd; 180a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 181a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGD("Creating ASEC image file %s (%d mb)", file, sizeMb); 182a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 183a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if ((fd = creat(file, 0600)) < 0) { 184a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Error creating imagefile (%s)", strerror(errno)); 185a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 186a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 187a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat 188a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat if (ftruncate(fd, (sizeMb * (1024 * 1024))) < 0) { 189a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat LOGE("Error truncating imagefile (%s)", strerror(errno)); 190a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 191a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return -1; 192a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat } 193a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat close(fd); 194a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat return 0; 195a19b250bd273455933ca3502cf2c2e0a803aff77San Mehat} 196