Files
nomad/client/pluginmanager/csimanager/interface.go
Tim Gross f3fc54adcf CSI: set mounts in alloc hook resources atomically (#16722)
The allocrunner has a facility for passing data written by allocrunner hooks to
taskrunner hooks. Currently the only consumers of this facility are the
allocrunner CSI hook (which writes data) and the taskrunner volume hook (which
reads that same data).

The allocrunner hook for CSI volumes doesn't set the alloc hook resources
atomically. Instead, it gets the current resources and then writes a new version
back. Because the CSI hook is currently the only writer and all readers happen
long afterwards, this should be safe but #16623 shows there's some sequence of
events during restore where this breaks down.

Refactor hook resources so that hook data is accessed via setters and getters
that hold the mutex.
2023-04-03 11:03:36 -04:00

69 lines
1.8 KiB
Go

package csimanager
import (
"context"
"strings"
"github.com/hashicorp/nomad/client/pluginmanager"
"github.com/hashicorp/nomad/nomad/structs"
)
type MountInfo struct {
Source string
IsDevice bool
}
func (mi *MountInfo) Copy() *MountInfo {
if mi == nil {
return nil
}
nmi := new(MountInfo)
*nmi = *mi
return nmi
}
type UsageOptions struct {
ReadOnly bool
AttachmentMode structs.CSIVolumeAttachmentMode
AccessMode structs.CSIVolumeAccessMode
MountOptions *structs.CSIMountOptions
}
// ToFS is used by a VolumeManager to construct the path to where a volume
// should be staged/published. It should always return a string that is easy
// enough to manage as a filesystem path segment (e.g avoid starting the string
// with a special character).
func (u *UsageOptions) ToFS() string {
var sb strings.Builder
if u.ReadOnly {
sb.WriteString("ro-")
} else {
sb.WriteString("rw-")
}
sb.WriteString(string(u.AttachmentMode))
sb.WriteString("-")
sb.WriteString(string(u.AccessMode))
return sb.String()
}
type VolumeMounter interface {
MountVolume(ctx context.Context, vol *structs.CSIVolume, alloc *structs.Allocation, usageOpts *UsageOptions, publishContext map[string]string) (*MountInfo, error)
UnmountVolume(ctx context.Context, volID, remoteID, allocID string, usageOpts *UsageOptions) error
}
type Manager interface {
// PluginManager returns a PluginManager for use by the node fingerprinter.
PluginManager() pluginmanager.PluginManager
// MounterForPlugin returns a VolumeMounter for the plugin ID associated
// with the volume. Returns an error if this plugin isn't registered.
MounterForPlugin(ctx context.Context, pluginID string) (VolumeMounter, error)
// Shutdown shuts down the Manager and unmounts any locally attached volumes.
Shutdown()
}