Files
podman/pkg/machine/volumes.go
Colin Walters bf541c6740 machine/linux: Support virtiofs mounts (retain 9p default)
I'm hitting a bug with 9p when trying to transfer large files.
In RHEL at least 9p isn't supported because it's known to have a
lot of design flaws; virtiofsd is the supported and recommended
way to share files between a host and guest.

Add a new hidden `PODMAN_MACHINE_VIRTFS` environment
variable  that can be set to `virtiofs` to switch to virtiofsd.

Signed-off-by: Colin Walters <walters@verbum.org>
2024-06-07 10:03:06 -04:00

79 lines
1.7 KiB
Go

package machine
import (
"crypto/sha256"
"encoding/hex"
"github.com/containers/podman/v5/pkg/machine/vmconfigs"
)
// NFSSELinuxContext is what is used by NFS mounts, which is allowed
// access by container_t. We need to fix the Fedora selinux policy
// to just allow access to virtiofs_t.
const NFSSELinuxContext = "system_u:object_r:nfs_t:s0"
type Volume interface {
Kind() VolumeKind
}
type VolumeKind string
var (
VirtIOFsVk VolumeKind = "virtiofs"
NinePVk VolumeKind = "9p"
)
type VirtIoFs struct {
VolumeKind
ReadOnly bool
Source string
Tag string
Target string
}
func (v VirtIoFs) Kind() string {
return string(VirtIOFsVk)
}
// generateTag generates a tag for VirtIOFs mounts.
// AppleHV requires tags to be 36 bytes or fewer.
// SHA256 the path, then truncate to 36 bytes
func (v VirtIoFs) generateTag() string {
sum := sha256.Sum256([]byte(v.Target))
stringSum := hex.EncodeToString(sum[:])
return stringSum[:36]
}
func (v VirtIoFs) ToMount() vmconfigs.Mount {
return vmconfigs.Mount{
ReadOnly: v.ReadOnly,
Source: v.Source,
Tag: v.Tag,
Target: v.Target,
Type: v.Kind(),
}
}
// NewVirtIoFsMount describes a machine volume mount for virtio-fs. With virtio-fs
// the source/target are described as a "shared dir". With this style of volume mount
// the Tag is used as the descriptor value for the mount (in Linux).
func NewVirtIoFsMount(src, target string, readOnly bool) VirtIoFs {
vfs := VirtIoFs{
ReadOnly: readOnly,
Source: src,
Target: target,
}
vfs.Tag = vfs.generateTag()
return vfs
}
func MountToVirtIOFs(mnt *vmconfigs.Mount) VirtIoFs {
return VirtIoFs{
VolumeKind: VirtIOFsVk,
ReadOnly: mnt.ReadOnly,
Source: mnt.Source,
Tag: mnt.Tag,
Target: mnt.Target,
}
}