This takes the latest changes from AOSP from [1][2] (as this header was split on two) with minimal changes (this could lead to warnings reported by checkpatch).
Some local changes have been applied: 1. Enable static_assert() for defined structures to be sure that all of them have correct sizes. 2. Adjuste types in bootloader_control structure with bitfields (uint8_t -> uint16_t). It seems that gcc just doesn't like bitfields that cross the width of the type. Changing the type doesn't change the layout though. This addresses this gcc note: In file included from boot/android_ab.c:7: include/android_bootloader_message.h:230:1: note: offset of packed bit-field ‘merge_status’ has changed in GCC 4.4 230 | } __attribute__((packed));
[1] https://android.googlesource.com/platform/bootable/recovery/+/main/bootloade... [2] https://android.googlesource.com/platform/hardware/interfaces/+/main/boot/1....
CC: Alex Deymo deymo@google.com CC: Sam Protsenko semen.protsenko@linaro.org CC: Eugeniu Rosca erosca@de.adit-jv.com CC: Simon Glass sjg@chromium.org Signed-off-by: Igor Opaniuk igor.opaniuk@gmail.com ---
include/android_bootloader_message.h | 104 +++++++++++++++++++++++---- 1 file changed, 92 insertions(+), 12 deletions(-)
diff --git a/include/android_bootloader_message.h b/include/android_bootloader_message.h index 286d7ab0f31..75198fc9dc2 100644 --- a/include/android_bootloader_message.h +++ b/include/android_bootloader_message.h @@ -21,17 +21,22 @@ * stddef.h */ #include <compiler.h> +#include <linux/build_bug.h> #endif
// Spaces used by misc partition are as below: // 0 - 2K For bootloader_message // 2K - 16K Used by Vendor's bootloader (the 2K - 4K range may be optionally used // as bootloader_message_ab struct) -// 16K - 64K Used by uncrypt and recovery to store wipe_package for A/B devices +// 16K - 32K Used by uncrypt and recovery to store wipe_package for A/B devices +// 32K - 64K System space, used for miscellanious AOSP features. See below. // Note that these offsets are admitted by bootloader,recovery and uncrypt, so they // are not configurable without changing all of them. static const size_t BOOTLOADER_MESSAGE_OFFSET_IN_MISC = 0; +static const size_t VENDOR_SPACE_OFFSET_IN_MISC = 2 * 1024; static const size_t WIPE_PACKAGE_OFFSET_IN_MISC = 16 * 1024; +static const size_t SYSTEM_SPACE_OFFSET_IN_MISC = 32 * 1024; +static const size_t SYSTEM_SPACE_SIZE_IN_MISC = 32 * 1024;
/* Bootloader Message (2-KiB) * @@ -81,24 +86,67 @@ struct bootloader_message { char reserved[1184]; };
+// Holds Virtual A/B merge status information. Current version is 1. New fields +// must be added to the end. +struct misc_virtual_ab_message { + uint8_t version; + uint32_t magic; + uint8_t merge_status; // IBootControl 1.1, MergeStatus enum. + uint8_t source_slot; // Slot number when merge_status was written. + uint8_t reserved[57]; +} __attribute__((packed)); + +struct misc_memtag_message { + uint8_t version; + uint32_t magic; // magic string for treble compat + uint32_t memtag_mode; + uint8_t reserved[55]; +} __attribute__((packed)); + +struct misc_kcmdline_message { + uint8_t version; + uint32_t magic; + uint64_t kcmdline_flags; + uint8_t reserved[51]; +} __attribute__((packed)); + +#define MISC_VIRTUAL_AB_MESSAGE_VERSION 2 +#define MISC_VIRTUAL_AB_MAGIC_HEADER 0x56740AB0 + +#define MISC_MEMTAG_MESSAGE_VERSION 1 +#define MISC_MEMTAG_MAGIC_HEADER 0x5afefe5a +#define MISC_MEMTAG_MODE_MEMTAG 0x1 +#define MISC_MEMTAG_MODE_MEMTAG_ONCE 0x2 +#define MISC_MEMTAG_MODE_MEMTAG_KERNEL 0x4 +#define MISC_MEMTAG_MODE_MEMTAG_KERNEL_ONCE 0x8 +#define MISC_MEMTAG_MODE_MEMTAG_OFF 0x10 +// This is set when the state was overridden forcibly. This does not need to be +// interpreted by the bootloader but is only for bookkeeping purposes so +// userspace knows what to do when the override is undone. +// See system/extras/mtectrl in AOSP for more information. +#define MISC_MEMTAG_MODE_FORCED 0x20 + +#define MISC_KCMDLINE_MESSAGE_VERSION 1 +#define MISC_KCMDLINE_MAGIC_HEADER 0x6ab5110c +#define MISC_KCMDLINE_BINDER_RUST 0x1 /** * We must be cautious when changing the bootloader_message struct size, * because A/B-specific fields may end up with different offsets. */ -#ifndef __UBOOT__ + #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_message) == 2048, "struct bootloader_message size changes, which may break A/B devices"); #endif -#endif /* __UBOOT__ */
/** * The A/B-specific bootloader message structure (4-KiB). * * We separate A/B boot control metadata from the regular bootloader * message struct and keep it here. Everything that's A/B-specific - * stays after struct bootloader_message, which should be managed by - * the A/B-bootloader or boot control HAL. + * stays after struct bootloader_message, which belongs to the vendor + * space of /misc partition. Also, the A/B-specific contents should be + * managed by the A/B-bootloader or boot control HAL. * * The slot_suffix field is used for A/B implementations where the * bootloader does not set the androidboot.ro.boot.slot_suffix kernel @@ -124,12 +172,10 @@ struct bootloader_message_ab { * Be cautious about the struct size change, in case we put anything post * bootloader_message_ab struct (b/29159185). */ -#ifndef __UBOOT__ #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_message_ab) == 4096, "struct bootloader_message_ab size changes"); #endif -#endif /* __UBOOT__ */
#define BOOT_CTRL_MAGIC 0x42414342 /* Bootloader Control AB */ #define BOOT_CTRL_VERSION 1 @@ -165,11 +211,13 @@ struct bootloader_control { // Version of struct being used (see BOOT_CTRL_VERSION). uint8_t version; // Number of slots being managed. - uint8_t nb_slot : 3; + uint16_t nb_slot : 3; // Number of times left attempting to boot recovery. - uint8_t recovery_tries_remaining : 3; + uint16_t recovery_tries_remaining : 3; + // Status of any pending snapshot merge of dynamic partitions. + uint16_t merge_status : 3; // Ensure 4-bytes alignment for slot_info field. - uint8_t reserved0[2]; + uint8_t reserved0[1]; // Per-slot information. Up to 4 slots. struct slot_metadata slot_info[4]; // Reserved for further use. @@ -179,25 +227,46 @@ struct bootloader_control { uint32_t crc32_le; } __attribute__((packed));
-#ifndef __UBOOT__ #if (__STDC_VERSION__ >= 201112L) || defined(__cplusplus) static_assert(sizeof(struct bootloader_control) == sizeof(((struct bootloader_message_ab *)0)->slot_suffix), "struct bootloader_control has wrong size"); +static_assert(sizeof(struct misc_virtual_ab_message) == 64, + "struct misc_virtual_ab_message has wrong size"); +static_assert(sizeof(struct misc_memtag_message) == 64, + "struct misc_memtag_message has wrong size"); +static_assert(sizeof(struct misc_kcmdline_message) == 64, + "struct misc_kcmdline_message has wrong size"); #endif -#endif /* __UBOOT__ */
#ifndef __UBOOT__ + +// This struct is not meant to be used directly, rather, it is to make +// computation of offsets easier. New fields must be added to the end. +struct misc_system_space_layout { + misc_virtual_ab_message virtual_ab_message; + misc_memtag_message memtag_message; + misc_kcmdline_message kcmdline_message; +} __attribute__((packed)); + #ifdef __cplusplus
#include <string> #include <vector>
+// Gets the block device name of /misc partition. +std::string get_misc_blk_device(std::string* err); + // Return the block device name for the bootloader message partition and waits // for the device for up to 10 seconds. In case of error returns the empty // string. std::string get_bootloader_message_blk_device(std::string* err);
+// Writes |size| bytes of data from buffer |p| to |misc_blk_device| at |offset|. If the write fails, +// sets the error message in |err|. +bool write_misc_partition(const void* p, size_t size, const std::string& misc_blk_device, + size_t offset, std::string* err); + // Read bootloader message into boot. Error message will be set in err. bool read_bootloader_message(bootloader_message* boot, std::string* err);
@@ -242,6 +311,17 @@ bool read_wipe_package(std::string* package_data, size_t size, std::string* err) // Write the wipe package into BCB (to offset WIPE_PACKAGE_OFFSET_IN_MISC). bool write_wipe_package(const std::string& package_data, std::string* err);
+// Read or write the Virtual A/B message from system space in /misc. +bool ReadMiscVirtualAbMessage(misc_virtual_ab_message* message, std::string* err); +bool WriteMiscVirtualAbMessage(const misc_virtual_ab_message& message, std::string* err); + +// Read or write the memtag message from system space in /misc. +bool ReadMiscMemtagMessage(misc_memtag_message* message, std::string* err); +bool WriteMiscMemtagMessage(const misc_memtag_message& message, std::string* err); + +// Read or write the kcmdline message from system space in /misc. +bool ReadMiscKcmdlineMessage(misc_kcmdline_message* message, std::string* err); +bool WriteMiscKcmdlineMessage(const misc_kcmdline_message& message, std::string* err); #else
#include <stdbool.h>