All commonly used filesystems should use ref-counted mounter, so make it
the default instead of having to whitelist them.
Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>
BaseFS is not serialized and is lost after an unclean shutdown. Unmount
method in the containerd image service implementation will not work
correctly in that case.
This patch will allow Unmount to restore the BaseFS if the target is
still mounted.
The reason it works with graphdrivers is that it doesn't directly
operate on BaseFS. It uses RWLayer, which is explicitly restored
immediately as soon as container is loaded.
Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>
Change the non-refcounted implementation to perform the mount using the
same identity and access right. They should be the same regardless if
we're refcounting or not.
This also allows to refactor refCountMounter into a mounter decorator.
Signed-off-by: Paweł Gronowski <pawel.gronowski@docker.com>
The github.com/containerd/containerd/log package was moved to a separate
module, which will also be used by upcoming (patch) releases of containerd.
This patch moves our own uses of the package to use the new module.
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
Graph drivers create the parent directory with
rootPair().GID:CurrentIdentity().UID owner. This change brings these in
line
Signed-off-by: Djordje Lukic <djordje.lukic@docker.com>
The stargz snapshotter cannot be re-mounted, so the reference-counted
path must be used.
Co-authored-by: Djordje Lukic <djordje.lukic@docker.com>
Signed-off-by: Bjorn Neergaard <bjorn.neergaard@docker.com>
Some snapshotters (like overlayfs or zfs) can't mount the same
directories twice. For example if the same directroy is used as an upper
directory in two mounts the kernel will output this warning:
overlayfs: upperdir is in-use as upperdir/workdir of another mount, accessing files from both mounts will result in undefined behavior.
And indeed accessing the files from both mounts will result in an "No
such file or directory" error.
This change introduces reference counts for the mounts, if a directory
is already mounted the mount interface will only increment the mount
counter and return the mount target effectively making sure that the
filesystem doesn't end up in an undefined behavior.
Signed-off-by: Djordje Lukic <djordje.lukic@docker.com>
