1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <errno.h> 18 #include <stdlib.h> 19 #include <sys/mount.h> 20 #include <sys/stat.h> 21 #include <sys/types.h> 22 #include <unistd.h> 23 #include <ctype.h> 24 25 #include "mtdutils/mtdutils.h" 26 #include "mtdutils/mounts.h" 27 #include "roots.h" 28 #include "common.h" 29 #include "make_ext4fs.h" 30 31 static int num_volumes = 0; 32 static Volume* device_volumes = NULL; 33 34 void load_volume_table() { 35 int alloc = 2; 36 device_volumes = malloc(alloc * sizeof(Volume)); 37 38 // Insert an entry for /tmp, which is the ramdisk and is always mounted. 39 device_volumes[0].mount_point = "/tmp"; 40 device_volumes[0].fs_type = "ramdisk"; 41 device_volumes[0].device = NULL; 42 device_volumes[0].device2 = NULL; 43 num_volumes = 1; 44 45 FILE* fstab = fopen("/etc/recovery.fstab", "r"); 46 if (fstab == NULL) { 47 LOGE("failed to open /etc/recovery.fstab (%s)\n", strerror(errno)); 48 return; 49 } 50 51 char buffer[1024]; 52 int i; 53 while (fgets(buffer, sizeof(buffer)-1, fstab)) { 54 for (i = 0; buffer[i] && isspace(buffer[i]); ++i); 55 if (buffer[i] == '\0' || buffer[i] == '#') continue; 56 57 char* original = strdup(buffer); 58 59 char* mount_point = strtok(buffer+i, " \t\n"); 60 char* fs_type = strtok(NULL, " \t\n"); 61 char* device = strtok(NULL, " \t\n"); 62 // lines may optionally have a second device, to use if 63 // mounting the first one fails. 64 char* device2 = strtok(NULL, " \t\n"); 65 66 if (mount_point && fs_type && device) { 67 while (num_volumes >= alloc) { 68 alloc *= 2; 69 device_volumes = realloc(device_volumes, alloc*sizeof(Volume)); 70 } 71 device_volumes[num_volumes].mount_point = strdup(mount_point); 72 device_volumes[num_volumes].fs_type = strdup(fs_type); 73 device_volumes[num_volumes].device = strdup(device); 74 device_volumes[num_volumes].device2 = 75 device2 ? strdup(device2) : NULL; 76 ++num_volumes; 77 } else { 78 LOGE("skipping malformed recovery.fstab line: %s\n", original); 79 } 80 free(original); 81 } 82 83 fclose(fstab); 84 85 printf("recovery filesystem table\n"); 86 printf("=========================\n"); 87 for (i = 0; i < num_volumes; ++i) { 88 Volume* v = &device_volumes[i]; 89 printf(" %d %s %s %s %s\n", i, v->mount_point, v->fs_type, 90 v->device, v->device2); 91 } 92 printf("\n"); 93 } 94 95 Volume* volume_for_path(const char* path) { 96 int i; 97 for (i = 0; i < num_volumes; ++i) { 98 Volume* v = device_volumes+i; 99 int len = strlen(v->mount_point); 100 if (strncmp(path, v->mount_point, len) == 0 && 101 (path[len] == '\0' || path[len] == '/')) { 102 return v; 103 } 104 } 105 return NULL; 106 } 107 108 int ensure_path_mounted(const char* path) { 109 Volume* v = volume_for_path(path); 110 if (v == NULL) { 111 LOGE("unknown volume for path [%s]\n", path); 112 return -1; 113 } 114 if (strcmp(v->fs_type, "ramdisk") == 0) { 115 // the ramdisk is always mounted. 116 return 0; 117 } 118 119 int result; 120 result = scan_mounted_volumes(); 121 if (result < 0) { 122 LOGE("failed to scan mounted volumes\n"); 123 return -1; 124 } 125 126 const MountedVolume* mv = 127 find_mounted_volume_by_mount_point(v->mount_point); 128 if (mv) { 129 // volume is already mounted 130 return 0; 131 } 132 133 mkdir(v->mount_point, 0755); // in case it doesn't already exist 134 135 if (strcmp(v->fs_type, "yaffs2") == 0) { 136 // mount an MTD partition as a YAFFS2 filesystem. 137 mtd_scan_partitions(); 138 const MtdPartition* partition; 139 partition = mtd_find_partition_by_name(v->device); 140 if (partition == NULL) { 141 LOGE("failed to find \"%s\" partition to mount at \"%s\"\n", 142 v->device, v->mount_point); 143 return -1; 144 } 145 return mtd_mount_partition(partition, v->mount_point, v->fs_type, 0); 146 } else if (strcmp(v->fs_type, "ext4") == 0 || 147 strcmp(v->fs_type, "vfat") == 0) { 148 result = mount(v->device, v->mount_point, v->fs_type, 149 MS_NOATIME | MS_NODEV | MS_NODIRATIME, ""); 150 if (result == 0) return 0; 151 152 if (v->device2) { 153 LOGW("failed to mount %s (%s); trying %s\n", 154 v->device, strerror(errno), v->device2); 155 result = mount(v->device2, v->mount_point, v->fs_type, 156 MS_NOATIME | MS_NODEV | MS_NODIRATIME, ""); 157 if (result == 0) return 0; 158 } 159 160 LOGE("failed to mount %s (%s)\n", v->mount_point, strerror(errno)); 161 return -1; 162 } 163 164 LOGE("unknown fs_type \"%s\" for %s\n", v->fs_type, v->mount_point); 165 return -1; 166 } 167 168 int ensure_path_unmounted(const char* path) { 169 Volume* v = volume_for_path(path); 170 if (v == NULL) { 171 LOGE("unknown volume for path [%s]\n", path); 172 return -1; 173 } 174 if (strcmp(v->fs_type, "ramdisk") == 0) { 175 // the ramdisk is always mounted; you can't unmount it. 176 return -1; 177 } 178 179 int result; 180 result = scan_mounted_volumes(); 181 if (result < 0) { 182 LOGE("failed to scan mounted volumes\n"); 183 return -1; 184 } 185 186 const MountedVolume* mv = 187 find_mounted_volume_by_mount_point(v->mount_point); 188 if (mv == NULL) { 189 // volume is already unmounted 190 return 0; 191 } 192 193 return unmount_mounted_volume(mv); 194 } 195 196 int format_volume(const char* volume) { 197 Volume* v = volume_for_path(volume); 198 if (v == NULL) { 199 LOGE("unknown volume \"%s\"\n", volume); 200 return -1; 201 } 202 if (strcmp(v->fs_type, "ramdisk") == 0) { 203 // you can't format the ramdisk. 204 LOGE("can't format_volume \"%s\"", volume); 205 return -1; 206 } 207 if (strcmp(v->mount_point, volume) != 0) { 208 LOGE("can't give path \"%s\" to format_volume\n", volume); 209 return -1; 210 } 211 212 if (ensure_path_unmounted(volume) != 0) { 213 LOGE("format_volume failed to unmount \"%s\"\n", v->mount_point); 214 return -1; 215 } 216 217 if (strcmp(v->fs_type, "yaffs2") == 0 || strcmp(v->fs_type, "mtd") == 0) { 218 mtd_scan_partitions(); 219 const MtdPartition* partition = mtd_find_partition_by_name(v->device); 220 if (partition == NULL) { 221 LOGE("format_volume: no MTD partition \"%s\"\n", v->device); 222 return -1; 223 } 224 225 MtdWriteContext *write = mtd_write_partition(partition); 226 if (write == NULL) { 227 LOGW("format_volume: can't open MTD \"%s\"\n", v->device); 228 return -1; 229 } else if (mtd_erase_blocks(write, -1) == (off_t) -1) { 230 LOGW("format_volume: can't erase MTD \"%s\"\n", v->device); 231 mtd_write_close(write); 232 return -1; 233 } else if (mtd_write_close(write)) { 234 LOGW("format_volume: can't close MTD \"%s\"\n", v->device); 235 return -1; 236 } 237 return 0; 238 } 239 240 if (strcmp(v->fs_type, "ext4") == 0) { 241 reset_ext4fs_info(); 242 int result = make_ext4fs(v->device, NULL, NULL, 0, 0, 0); 243 if (result != 0) { 244 LOGE("format_volume: make_extf4fs failed on %s\n", v->device); 245 return -1; 246 } 247 return 0; 248 } 249 250 LOGE("format_volume: fs_type \"%s\" unsupported\n", v->fs_type); 251 return -1; 252 } 253