From a090301bbb10424ce4f99e40c97959f0e8664718 Mon Sep 17 00:00:00 2001 From: Valentin Rothberg Date: Tue, 2 Mar 2021 09:20:53 +0100 Subject: podman cp: support copying on tmpfs mounts Traditionally, the path resolution for containers has been resolved on the *host*; relative to the container's mount point or relative to specified bind mounts or volumes. While this works nicely for non-running containers, it poses a problem for running ones. In that case, certain kinds of mounts (e.g., tmpfs) will not resolve correctly. A tmpfs is held in memory and hence cannot be resolved relatively to the container's mount point. A copy operation will succeed but the data will not show up inside the container. To support these kinds of mounts, we need to join the *running* container's mount namespace (and PID namespace) when copying. Note that this change implies moving the copy and stat logic into `libpod` since we need to keep the container locked to avoid race conditions. The immediate benefit is that all logic is now inside `libpod`; the code isn't scattered anymore. Further note that Docker does not support copying to tmpfs mounts. Tests have been extended to cover *both* path resolutions for running and created containers. New tests have been added to exercise the tmpfs-mount case. For the record: Some tests could be improved by using `start -a` instead of a start-exec sequence. Unfortunately, `start -a` is flaky in the CI which forced me to use the more expensive start-exec option. Signed-off-by: Valentin Rothberg --- pkg/copy/fileinfo.go | 11 ++--------- 1 file changed, 2 insertions(+), 9 deletions(-) (limited to 'pkg/copy') diff --git a/pkg/copy/fileinfo.go b/pkg/copy/fileinfo.go index b95bcd90c..fb711311c 100644 --- a/pkg/copy/fileinfo.go +++ b/pkg/copy/fileinfo.go @@ -7,8 +7,8 @@ import ( "os" "path/filepath" "strings" - "time" + "github.com/containers/podman/v3/libpod/define" "github.com/pkg/errors" ) @@ -22,14 +22,7 @@ var ErrENOENT = errors.New("No such file or directory") // FileInfo describes a file or directory and is returned by // (*CopyItem).Stat(). -type FileInfo struct { - Name string `json:"name"` - Size int64 `json:"size"` - Mode os.FileMode `json:"mode"` - ModTime time.Time `json:"mtime"` - IsDir bool `json:"isDir"` - LinkTarget string `json:"linkTarget"` -} +type FileInfo = define.FileInfo // EncodeFileInfo serializes the specified FileInfo as a base64 encoded JSON // payload. Intended for Docker compat. -- cgit v1.2.3-54-g00ecf