commit 2ee6ea060a48b56672787e28ce0b5cf7861f2f98
author bowgotsai <bowgotsai@google.com> Thu Feb 09 22:21:54 2017 +0800
committer bowgotsai <bowgotsai@google.com> Fri Feb 10 02:20:22 2017 +0800
tree 1f488f5c759aab9c5e0a596a2f3457b8095acf3b
parent 4428b388edddb49fa340de043b36a0aa4ee182be

fs_mgr: removing the dependency of requiring /vbmeta in fstab for AVB

Remove polling_vbmeta_blk_device() as it tries to get /vbmeta entry
from fstab. Also move the polling of a partition inside read_from_partition()
in fs_mgr_avb_ops.cpp as it's where the reads happen.

Bug: 31264231
Test: Device can boot with AVB

Change-Id: Id717e160b085eca42eb9bc5eb2fa7e658bea3ad6

fs_mgr/fs_mgr_avb.cpp

diff --git a/fs_mgr/fs_mgr_avb.cpp b/fs_mgr/fs_mgr_avb.cpp
index 70140d8..dd08271 100644
--- a/fs_mgr/fs_mgr_avb.cpp
+++ b/fs_mgr/fs_mgr_avb.cpp
@@ -215,8 +215,8 @@
 
     // Reads digest.
     if (digest.size() != expected_digest_size) {
-        LERROR << "Unexpected digest size: " << digest.size() << " (expected: "
-               << expected_digest_size << ")";
+        LERROR << "Unexpected digest size: " << digest.size()
+               << " (expected: " << expected_digest_size << ")";
         return false;
     }
 
@@ -482,22 +482,6 @@
     return true;
 }
 
-static inline bool polling_vbmeta_blk_device(struct fstab *fstab)
-{
-    // It needs the block device symlink: fstab_rec->blk_device to read
-    // /vbmeta partition. However, the symlink created by ueventd might
-    // not be ready at this point. Use test_access() to poll it before
-    // trying to read the partition.
-    struct fstab_rec *fstab_entry =
-        fs_mgr_get_entry_for_mount_point(fstab, "/vbmeta");
-
-    // Makes sure /vbmeta block device is ready to access.
-    if (fs_mgr_test_access(fstab_entry->blk_device) < 0) {
-        return false;
-    }
-    return true;
-}
-
 static bool init_is_avb_used()
 {
     // When AVB is used, boot loader should set androidboot.vbmeta.{hash_alg,
@@ -529,11 +513,6 @@
 {
     FS_MGR_CHECK(fstab != nullptr);
 
-    if (!polling_vbmeta_blk_device(fstab)) {
-        LERROR << "Failed to find block device of /vbmeta";
-        return FS_MGR_SETUP_AVB_FAIL;
-    }
-
     // Gets the expected hash value of vbmeta images from
     // kernel cmdline.
     if (!load_vbmeta_prop(&fs_mgr_vbmeta_prop)) {

fs_mgr/fs_mgr_avb_ops.cpp

diff --git a/fs_mgr/fs_mgr_avb_ops.cpp b/fs_mgr/fs_mgr_avb_ops.cpp
index 7683166..f96f124 100644
--- a/fs_mgr/fs_mgr_avb_ops.cpp
+++ b/fs_mgr/fs_mgr_avb_ops.cpp
@@ -66,7 +66,7 @@
         fs_mgr_get_entry_for_mount_point(fs_mgr_fstab, "/misc");
 
     if (fstab_entry == nullptr) {
-        LERROR << "Partition (" << partition << ") not found in fstab";
+        LERROR << "/misc mount point not found in fstab";
         return AVB_IO_RESULT_ERROR_IO;
     }
 
@@ -79,6 +79,13 @@
         path = by_name_prefix + partition_name;
     }
 
+    // Ensures the device path (a symlink created by init) is ready to
+    // access. fs_mgr_test_access() will test a few iterations if the
+    // path doesn't exist yet.
+    if (fs_mgr_test_access(path.c_str()) < 0) {
+        return AVB_IO_RESULT_ERROR_IO;
+    }
+
     android::base::unique_fd fd(
         TEMP_FAILURE_RETRY(open(path.c_str(), O_RDONLY | O_CLOEXEC)));