VirtualBox Shared Folder With Linux 5.14 Will Open New Files Faster, Fixes "git clone"

For those making use of VirtualBox virtualization and rely on the shared folder functionality via the mainline "VBOXSF" driver for exchanging files between VMs and the host, the in-development Linux 5.14 kernel has an important fix/improvement.

Red Hat's Hans de Goede saw his VBOXSF fixes merged today that most notably adds support for atomic_open directory-inode operation. This atomic_open functionality is based on the implementations found within Linux's 9p and FUSE code. This addition means it should be faster opening new files within VBOXSF-backed mounts. But besides being faster, it does also fix normal use-case too like up to now running "git clone" within a VirtualBox shared folder mount breaking things.

Thus now with these just-merged patches running "git clone" can survive in a shared folder directory without breaking. This problem has been known for months and even these patches by Hans available for months, but it's been a long process to get the patches reviewed and upstreamed.

It took Hans sending the pull directly to Linus Torvalds to get the VBOXSF driver improvements merged today rather than going through the normal file-system channels. Hans commented, "Linus, sorry for sending this directly through you, instead of going through some other tree, but trying to get this upstream through the linux-fsdevel list / patch-review simply is not working... This patch-set has been posted on the linux-fsdevel for the first time on January 21th 2021, so almost 6 months ago and I've send out several pings and a resend since then, but unfortunately no-one on the linux-fsdevel list seems to have interest in / time for reviewing vboxsf patches."

These patches were merged to mainline a few minutes ago for improving the VirtualBox shared folder functionality.