TL;DR: check for IsExist(err) after a failed MkdirAll() is both
redundant and wrong -- so two reasons to remove it.
Quoting MkdirAll documentation:
> MkdirAll creates a directory named path, along with any necessary
> parents, and returns nil, or else returns an error. If path
> is already a directory, MkdirAll does nothing and returns nil.
This means two things:
1. If a directory to be created already exists, no error is returned.
2. If the error returned is IsExist (EEXIST), it means there exists
a non-directory with the same name as MkdirAll need to use for
directory. Example: we want to MkdirAll("a/b"), but file "a"
(or "a/b") already exists, so MkdirAll fails.
The above is a theory, based on quoted documentation and my UNIX
knowledge.
3. In practice, though, current MkdirAll implementation [1] returns
ENOTDIR in most of cases described in #2, with the exception when
there is a race between MkdirAll and someone else creating the
last component of MkdirAll argument as a file. In this very case
MkdirAll() will indeed return EEXIST.
Because of #1, IsExist check after MkdirAll is not needed.
Because of #2 and #3, ignoring IsExist error is just plain wrong,
as directory we require is not created. It's cleaner to report
the error now.
Note this error is all over the tree, I guess due to copy-paste,
or trying to follow the same usage pattern as for Mkdir(),
or some not quite correct examples on the Internet.
[v2: a separate aufs commit is merged into this one]
[1] https://github.com/golang/go/blob/f9ed2f75/src/os/path.go
Signed-off-by: Kir Kolyshkin <kir@openvz.org>
The `ApplyDiff` function takes a tar archive stream that is
automagically decompressed later. This was causing a double
decompression, and when the layer was empty, that causes an early EOF.
Signed-off-by: Vincent Batts <vbatts@redhat.com>
The ZFS driver should raise proper errors when the ZFS utility is
missing or when there's no zfs partition active on the system. Raising the
proper errors make possible to silently ignore the ZFS storage
driver when no default storage driver is specified.
Previous to this commit it was no longer possible to start the
docker daemon in that way:
docker -d --storage-opt dm.loopdatasize=2GB
The above command resulted in an exit error because the ZFS driver
tried to use the storage options.
Signed-off-by: Flavio Castelli <fcastelli@suse.com>
Current default basesize is 10G. Change it to 100G. Reason being that for
some people 10G is turning out to be too small and we don't have capabilities
to grow it dyamically.
This is just overcommitting and no real space is allocated till container
actually writes data. And this is no different then fs based graphdrivers
where virtual size of a container root is unlimited.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Replaced github.com/docker/libcontainer with
github.com/opencontainers/runc/libcontaier.
Also I moved AppArmor profile generation to docker.
Main idea of this update is to fix mounting cgroups inside containers.
After updating docker on CI we can even remove dind.
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
The ability to save and verify base device UUID (#13896) introduced a
situation where the initialization would panic when removing the device
returns EBUSY.
Functions `verifyBaseDeviceUUID` and `saveBaseDeviceUUID` now take the
lock on the `DeviceSet`, which solves the problem as `removeDevice`
assumes it owns the lock.
Signed-off-by: Arnaud Porterie <arnaud.porterie@docker.com>
Often it happens that docker is not able to shutdown/remove the thin
pool it created because some device has leaked into some mount name
space. That means device is in use and that means pool can't be removed.
Docker will leave pool as it is and exit. Later when user starts the
docker, it finds pool is already there and docker uses it. But docker
does not know it is same pool which is using the loop devices. Now
docker thinks loop devices are not being used. That means it does not
display the data correctly in "docker info", giving user wrong information.
This patch tries to detect if loop devices as created by docker are
being used for pool and fills in the right details in "docker info".
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
DeviceMapper must be explicitly selected because the Docker binary might not be linked to the right devmapper library.
With this change, Docker fails fast if the driver detection finds the devicemapper directory but the driver is not the default option.
The option `override_udev_sync_check` doesn't make sense anymore, since the user must be explicit to select devicemapper, so it's being removed.
Docker fails to use devicemapper only if Docker has been built statically unless the option was explicit.
Signed-off-by: David Calavera <david.calavera@gmail.com>
Export metadata for container and image in docker-inspect when overlay
graphdriver is in use. Right now it is done only for devicemapper graph
driver.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
It is easy for one to use docker for a while, shut it down and restart
docker with different set of storage options for device mapper driver
which will effectively change the thin pool. That means any of the
metadata stored in /var/lib/docker/devicemapper/metadata/ is not valid
for the new pool and user will run into various kind of issues like
container not found in the pool etc.
Users think that their images or containers are lost but it might just
be the case of configuration issue. People might use wrong metadata
with wrong pool.
To detect such situations, save UUID of base image and once docker
starts later, query and compare the UUID of base image with the
stored one. If they don't match, fail the initialization with the
error that UUID failed to match.
That way user will be forced to cleanup /var/lib/docker/ directory
and start docker again.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Export image/container metadata stored in graph driver. Right now 3 fields
DeviceId, DeviceSize and DeviceName are being exported from devicemapper.
Other graph drivers can export fields as they see fit.
This data can be used to mount the thin device outside of docker and tools
can look into image/container and do some kind of inspection.
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Tibor Vass