Looking to use btrfs with disk images that contain ext4, xfs, and other possible filesystems. One of my main concerns is reclaiming disk space when files are deleted on the disk image's filesystem. Using fstrim on the mount point of the disk image or mounting the disk image (loop) with discard doesn't appear to pass the freed blocks to btrfs. The image file on the btrfs filesystem just keeps growing in size. When hosting images on ext4, using fstrim or discard frees up the space on the host filesystem (ext4). I see discard is pretty well supported for btrfs to the underlying block devices but is there any way to properly free space on the btrfs host filesystem from overlying filesystems while they are online? Thanks. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
