/* * Copyright (C) 2008 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #include "bootloader.h" #include "common.h" #include "mtdutils/mtdutils.h" #include "roots.h" #include <errno.h> #include <stdio.h> #include <string.h> #include <sys/stat.h> #include <unistd.h> static int get_bootloader_message_mtd(struct bootloader_message *out, const Volume* v); static int set_bootloader_message_mtd(const struct bootloader_message *in, const Volume* v); static int get_bootloader_message_block(struct bootloader_message *out, const Volume* v); static int set_bootloader_message_block(const struct bootloader_message *in, const Volume* v); int get_bootloader_message(struct bootloader_message *out) { Volume* v = volume_for_path("/misc"); if (v == NULL) { LOGE("Cannot load volume /misc!\n"); return -1; } if (strcmp(v->fs_type, "mtd") == 0) { return get_bootloader_message_mtd(out, v); } else if (strcmp(v->fs_type, "emmc") == 0) { return get_bootloader_message_block(out, v); } LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type); return -1; } int set_bootloader_message(const struct bootloader_message *in) { Volume* v = volume_for_path("/misc"); if (v == NULL) { LOGE("Cannot load volume /misc!\n"); return -1; } if (strcmp(v->fs_type, "mtd") == 0) { return set_bootloader_message_mtd(in, v); } else if (strcmp(v->fs_type, "emmc") == 0) { return set_bootloader_message_block(in, v); } LOGE("unknown misc partition fs_type \"%s\"\n", v->fs_type); return -1; } // ------------------------------ // for misc partitions on MTD // ------------------------------ static const int MISC_PAGES = 3; // number of pages to save static const int MISC_COMMAND_PAGE = 1; // bootloader command is this page static int get_bootloader_message_mtd(struct bootloader_message *out, const Volume* v) { size_t write_size; mtd_scan_partitions(); const MtdPartition *part = mtd_find_partition_by_name(v->device); if (part == NULL || mtd_partition_info(part, NULL, NULL, &write_size)) { LOGE("Can't find %s\n", v->device); return -1; } MtdReadContext *read = mtd_read_partition(part); if (read == NULL) { LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno)); return -1; } const ssize_t size = write_size * MISC_PAGES; char data[size]; ssize_t r = mtd_read_data(read, data, size); if (r != size) LOGE("Can't read %s\n(%s)\n", v->device, strerror(errno)); mtd_read_close(read); if (r != size) return -1; memcpy(out, &data[write_size * MISC_COMMAND_PAGE], sizeof(*out)); return 0; } static int set_bootloader_message_mtd(const struct bootloader_message *in, const Volume* v) { size_t write_size; mtd_scan_partitions(); const MtdPartition *part = mtd_find_partition_by_name(v->device); if (part == NULL || mtd_partition_info(part, NULL, NULL, &write_size)) { LOGE("Can't find %s\n", v->device); return -1; } MtdReadContext *read = mtd_read_partition(part); if (read == NULL) { LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno)); return -1; } ssize_t size = write_size * MISC_PAGES; char data[size]; ssize_t r = mtd_read_data(read, data, size); if (r != size) LOGE("Can't read %s\n(%s)\n", v->device, strerror(errno)); mtd_read_close(read); if (r != size) return -1; memcpy(&data[write_size * MISC_COMMAND_PAGE], in, sizeof(*in)); MtdWriteContext *write = mtd_write_partition(part); if (write == NULL) { LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno)); return -1; } if (mtd_write_data(write, data, size) != size) { LOGE("Can't write %s\n(%s)\n", v->device, strerror(errno)); mtd_write_close(write); return -1; } if (mtd_write_close(write)) { LOGE("Can't finish %s\n(%s)\n", v->device, strerror(errno)); return -1; } LOGI("Set boot command \"%s\"\n", in->command[0] != 255 ? in->command : ""); return 0; } // ------------------------------------ // for misc partitions on block devices // ------------------------------------ static void wait_for_device(const char* fn) { int tries = 0; int ret; struct stat buf; do { ++tries; ret = stat(fn, &buf); if (ret) { printf("stat %s try %d: %s\n", fn, tries, strerror(errno)); sleep(1); } } while (ret && tries < 10); if (ret) { printf("failed to stat %s\n", fn); } } static int get_bootloader_message_block(struct bootloader_message *out, const Volume* v) { wait_for_device(v->device); FILE* f = fopen(v->device, "rb"); if (f == NULL) { LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno)); return -1; } struct bootloader_message temp; int count = fread(&temp, sizeof(temp), 1, f); if (count != 1) { LOGE("Failed reading %s\n(%s)\n", v->device, strerror(errno)); return -1; } if (fclose(f) != 0) { LOGE("Failed closing %s\n(%s)\n", v->device, strerror(errno)); return -1; } memcpy(out, &temp, sizeof(temp)); return 0; } static int set_bootloader_message_block(const struct bootloader_message *in, const Volume* v) { wait_for_device(v->device); FILE* f = fopen(v->device, "wb"); if (f == NULL) { LOGE("Can't open %s\n(%s)\n", v->device, strerror(errno)); return -1; } int count = fwrite(in, sizeof(*in), 1, f); if (count != 1) { LOGE("Failed writing %s\n(%s)\n", v->device, strerror(errno)); return -1; } if (fclose(f) != 0) { LOGE("Failed closing %s\n(%s)\n", v->device, strerror(errno)); return -1; } return 0; }