diff options
Diffstat (limited to 'boot/android_ab.c')
| -rw-r--r-- | boot/android_ab.c | 86 |
1 files changed, 71 insertions, 15 deletions
diff --git a/boot/android_ab.c b/boot/android_ab.c index 2d7b3926665..73b55c196c4 100644 --- a/boot/android_ab.c +++ b/boot/android_ab.c @@ -85,11 +85,13 @@ static int ab_control_default(struct bootloader_control *abc) */ static int ab_control_create_from_disk(struct blk_desc *dev_desc, const struct disk_partition *part_info, - struct bootloader_control **abc) + struct bootloader_control **abc, + ulong offset) { ulong abc_offset, abc_blocks, ret; - abc_offset = offsetof(struct bootloader_message_ab, slot_suffix); + abc_offset = offset + + offsetof(struct bootloader_message_ab, slot_suffix); if (abc_offset % part_info->blksz) { log_err("ANDROID: Boot control block not block aligned.\n"); return -EINVAL; @@ -135,11 +137,12 @@ static int ab_control_create_from_disk(struct blk_desc *dev_desc, */ static int ab_control_store(struct blk_desc *dev_desc, const struct disk_partition *part_info, - struct bootloader_control *abc) + struct bootloader_control *abc, ulong offset) { ulong abc_offset, abc_blocks, ret; - abc_offset = offsetof(struct bootloader_message_ab, slot_suffix) / + abc_offset = offset + + offsetof(struct bootloader_message_ab, slot_suffix) / part_info->blksz; abc_blocks = DIV_ROUND_UP(sizeof(struct bootloader_control), part_info->blksz); @@ -181,15 +184,19 @@ static int ab_compare_slots(const struct slot_metadata *a, return 0; } -int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info) +int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info, + bool dec_tries) { struct bootloader_control *abc = NULL; u32 crc32_le; int slot, i, ret; bool store_needed = false; char slot_suffix[4]; +#if ANDROID_AB_BACKUP_OFFSET + struct bootloader_control *backup_abc = NULL; +#endif - ret = ab_control_create_from_disk(dev_desc, part_info, &abc); + ret = ab_control_create_from_disk(dev_desc, part_info, &abc, 0); if (ret < 0) { /* * This condition represents an actual problem with the code or @@ -199,22 +206,53 @@ int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info) return ret; } +#if ANDROID_AB_BACKUP_OFFSET + ret = ab_control_create_from_disk(dev_desc, part_info, &backup_abc, + ANDROID_AB_BACKUP_OFFSET); + if (ret < 0) { + free(abc); + return ret; + } +#endif + crc32_le = ab_control_compute_crc(abc); if (abc->crc32_le != crc32_le) { log_err("ANDROID: Invalid CRC-32 (expected %.8x, found %.8x),", crc32_le, abc->crc32_le); - log_err("re-initializing A/B metadata.\n"); - - ret = ab_control_default(abc); - if (ret < 0) { - free(abc); - return -ENODATA; +#if ANDROID_AB_BACKUP_OFFSET + crc32_le = ab_control_compute_crc(backup_abc); + if (backup_abc->crc32_le != crc32_le) { + log_err("ANDROID: Invalid backup CRC-32 ") + log_err("expected %.8x, found %.8x),", + crc32_le, backup_abc->crc32_le); +#endif + + log_err("re-initializing A/B metadata.\n"); + + ret = ab_control_default(abc); + if (ret < 0) { +#if ANDROID_AB_BACKUP_OFFSET + free(backup_abc); +#endif + free(abc); + return -ENODATA; + } +#if ANDROID_AB_BACKUP_OFFSET + } else { + /* + * Backup is valid. Copy it to the primary + */ + memcpy(abc, backup_abc, sizeof(*abc)); } +#endif store_needed = true; } if (abc->magic != BOOT_CTRL_MAGIC) { log_err("ANDROID: Unknown A/B metadata: %.8x\n", abc->magic); +#if ANDROID_AB_BACKUP_OFFSET + free(backup_abc); +#endif free(abc); return -ENODATA; } @@ -222,6 +260,9 @@ int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info) if (abc->version > BOOT_CTRL_VERSION) { log_err("ANDROID: Unsupported A/B metadata version: %.8x\n", abc->version); +#if ANDROID_AB_BACKUP_OFFSET + free(backup_abc); +#endif free(abc); return -ENODATA; } @@ -272,8 +313,10 @@ int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info) log_err("ANDROID: Attempting slot %c, tries remaining %d\n", BOOT_SLOT_NAME(slot), abc->slot_info[slot].tries_remaining); - abc->slot_info[slot].tries_remaining--; - store_needed = true; + if (dec_tries) { + abc->slot_info[slot].tries_remaining--; + store_needed = true; + } } if (slot >= 0) { @@ -294,8 +337,21 @@ int ab_select_slot(struct blk_desc *dev_desc, struct disk_partition *part_info) if (store_needed) { abc->crc32_le = ab_control_compute_crc(abc); - ab_control_store(dev_desc, part_info, abc); + ab_control_store(dev_desc, part_info, abc, 0); } + +#if ANDROID_AB_BACKUP_OFFSET + /* + * If the backup doesn't match the primary, write the primary + * to the backup offset + */ + if (memcmp(backup_abc, abc, sizeof(*abc)) != 0) { + ab_control_store(dev_desc, part_info, abc, + ANDROID_AB_BACKUP_OFFSET); + } + free(backup_abc); +#endif + free(abc); if (slot < 0) |