On Fri, Mar 05, 2021 at 09:37:26AM +0800, Chao Yu wrote:

quoted

+cleanup:
+	/*
+	 * Verity failed to be enabled, so clean up by truncating any verity
+	 * metadata that was written beyond i_size (both from cache and from
+	 * disk) and clearing FI_VERITY_IN_PROGRESS.
+	 */
+	truncate_inode_pages(inode->i_mapping, inode->i_size);
+	f2fs_truncate(inode);

Eric,

Truncation can fail due to a lot of reasons, if we fail in f2fs_truncate(),
do we need to at least print a message here? or it allows to keep those
meta/data silently.

I suppose we might as well, although hopefully there will already be a message
for the underlying failure reason too.  Also, f2fs_file_write_iter() has the
same issue too, right?

One other concern is that how do you think of covering truncate_inode_pages &
f2fs_truncate with F2FS_I(inode)->i_gc_rwsem[WRITE] lock to avoid racing with
GC, so that page cache won't be revalidated after truncate_inode_pages().

Yes, that does seem to be needed, due to the way the f2fs garbage collection
works.

- Eric