fiemap: add fsync after write split file name
If device abnormal restart during upgrade, update_engine just
created split cow image file and wrote the name to xxx-cow-img.img.
After restart, update_engine will report following err:
06-30 08:48:06.466 root 8918 8920 E gsid : Error removing image
product_b-cow-img: File name too long
That is because SplitFiemap::Create->DetermineMaximumFileSize
open xxx-cow-img.img to get some info, then fsync and unlink this
file.
On device use f2fs, after restart, f2fs_recover_fsync_data will
recover this file with inode block sync to ufs in following path:
DetermineMaximumFileSize
->FiemapWriter::Open
->AllocateFile
This make xxx-cow-img.img file content corruption.
Update_engine call TryCancelUpdate to clean up the residual files
of last upgrade, cannot read valid split file name from
xxx-cow-img.img, then report err log mentioned above.
Add fsync, f2fs can use correct inode to recover related files.
This can reduce the probability of this issue.
Test: abnormal restart when upgrade
Change-Id: Iceb3e5604d90495350c5fb1fb3433732372f3fec
Signed-off-by: lijiazi <lijiazi@xiaomi.com>
diff --git a/fs_mgr/libfiemap/split_fiemap_writer.cpp b/fs_mgr/libfiemap/split_fiemap_writer.cpp
index 36bb3df..8457066 100644
--- a/fs_mgr/libfiemap/split_fiemap_writer.cpp
+++ b/fs_mgr/libfiemap/split_fiemap_writer.cpp
@@ -136,6 +136,7 @@
return FiemapStatus::FromErrno(errno);
}
}
+ fsync(fd.get());
// Unset this bit, so we don't unlink on destruction.
out->creating_ = false;
