Parse fstab.goldfish file from ramdisk.img
This patch modifies the emulator to detect an fstab.goldfish
in ramdisk.img, and if present, use it to determine the exact
format of all partitions on the system.
This file should be present starting with Android 4.4 (KitKat).
The change is important because not all SDK system images have
the same settings, and it's hard to guess correctly from the
API level or kernel version.
This should make the emulator _much_ more reliable in the way it
setups partition images, in the wake of changing partition
formats during platform development (i.e. the format of the
cache partition has changed several times in AOSP and internal
trees, and not all development branches have the same value now,
this patch should make the emulator always select the right value
now, instead of getting it wrong in many cases).
BUG=15831221,15832082,15753975,15670063,15137521
Change-Id: I636784f7a28e3b546b859ca355fd5345abf14982
diff --git a/vl-android.c b/vl-android.c
index 2d4751a..7023b44 100644
--- a/vl-android.c
+++ b/vl-android.c
@@ -54,7 +54,9 @@
#include "android/log-rotate.h"
#include "modem_driver.h"
#include "android/filesystems/ext4_utils.h"
+#include "android/filesystems/fstab_parser.h"
#include "android/filesystems/partition_types.h"
+#include "android/filesystems/ramdisk_extractor.h"
#include "android/gps.h"
#include "android/hw-kmsg.h"
#include "android/hw-pipe-net.h"
@@ -1870,6 +1872,36 @@
}
+// Extract the partition type/format of a given partition image
+// from the content of fstab.goldfish.
+// |fstab| is the address of the fstab.goldfish data in memory.
+// |fstabSize| is its size in bytes.
+// |partitionName| is the name of the partition for debugging
+// purposes (e.g. 'userdata').
+// |partitionPath| is the partition path as it appears in the
+// fstab file (e.g. '/data').
+// On success, sets |*partitionType| to an appropriate value,
+// on failure (i.e. |partitionPath| does not appear in the fstab
+// file), leave the value untouched.
+void android_extractPartitionFormat(const char* fstab,
+ size_t fstabSize,
+ const char* partitionName,
+ const char* partitionPath,
+ AndroidPartitionType* partitionType) {
+ char* partFormat = NULL;
+ if (!android_parseFstabPartitionFormat(fstab, fstabSize, partitionPath,
+ &partFormat)) {
+ VERBOSE_PRINT(init, "Could not extract format of %s partition!",
+ partitionName);
+ return;
+ }
+ VERBOSE_PRINT(init, "Found format of %s partition: '%s'",
+ partitionName, partFormat);
+ *partitionType = androidPartitionType_fromString(partFormat);
+ free(partFormat);
+}
+
+
// List of value describing how to handle partition images in
// android_nand_add_image() below, when no initiali partition image
// file is provided.
@@ -3070,9 +3102,55 @@
}
}
+ // Determine format of all partition images, if possible.
+ // Note that _UNKNOWN means the file, if it exists, will be probed.
+ AndroidPartitionType system_partition_type =
+ ANDROID_PARTITION_TYPE_UNKNOWN;
+ AndroidPartitionType userdata_partition_type =
+ ANDROID_PARTITION_TYPE_UNKNOWN;
+ AndroidPartitionType cache_partition_type =
+ ANDROID_PARTITION_TYPE_UNKNOWN;
+
+ {
+ // Starting with Android 4.4.x, the ramdisk.img contains
+ // an fstab.goldfish file that lists the format of each partition.
+ // If the file exists, parse it to get the appropriate values.
+ char* fstab = NULL;
+ size_t fstabSize = 0;
+
+ if (android_extractRamdiskFile(android_hw->disk_ramdisk_path,
+ "fstab.goldfish",
+ &fstab,
+ &fstabSize)) {
+ VERBOSE_PRINT(init, "Ramdisk image contains fstab.goldfish file");
+
+ android_extractPartitionFormat(fstab,
+ fstabSize,
+ "system",
+ "/system",
+ &system_partition_type);
+
+ android_extractPartitionFormat(fstab,
+ fstabSize,
+ "userdata",
+ "/data",
+ &userdata_partition_type);
+
+ android_extractPartitionFormat(fstab,
+ fstabSize,
+ "cache",
+ "/cache",
+ &cache_partition_type);
+
+ free(fstab);
+ } else {
+ VERBOSE_PRINT(init, "No fstab.goldfish file in ramdisk image");
+ }
+ }
+
/* Initialize system partition image */
android_nand_add_image("system",
- ANDROID_PARTITION_TYPE_UNKNOWN,
+ system_partition_type,
ANDROID_PARTITION_OPEN_MODE_MUST_EXIST,
android_hw->disk_systemPartition_size,
android_hw->disk_systemPartition_path,
@@ -3080,7 +3158,7 @@
/* Initialize data partition image */
android_nand_add_image("userdata",
- ANDROID_PARTITION_TYPE_UNKNOWN,
+ userdata_partition_type,
ANDROID_PARTITION_OPEN_MODE_CREATE_IF_NEEDED,
android_hw->disk_dataPartition_size,
android_hw->disk_dataPartition_path,
@@ -3091,19 +3169,21 @@
* YAFFS2 otherwise.
*/
if (android_hw->disk_cachePartition != 0) {
- AndroidPartitionType cache_part_type =
+ if (cache_partition_type == ANDROID_PARTITION_TYPE_UNKNOWN) {
+ cache_partition_type =
(androidHwConfig_getKernelYaffs2Support(android_hw) >= 1) ?
ANDROID_PARTITION_TYPE_YAFFS2 :
ANDROID_PARTITION_TYPE_EXT4;
+ }
- AndroidPartitionOpenMode cache_part_mode =
+ AndroidPartitionOpenMode cache_partition_mode =
(android_op_wipe_data ?
ANDROID_PARTITION_OPEN_MODE_MUST_WIPE :
ANDROID_PARTITION_OPEN_MODE_CREATE_IF_NEEDED);
android_nand_add_image("cache",
- cache_part_type,
- cache_part_mode,
+ cache_partition_type,
+ cache_partition_mode,
android_hw->disk_cachePartition_size,
android_hw->disk_cachePartition_path,
NULL);