podman/libpod/runtime_renumber.go

//go:build !remote && (linux || freebsd)

package libpod

import (
	"fmt"

	"go.podman.io/podman/v6/libpod/define"
	"go.podman.io/podman/v6/libpod/events"
)

// RenumberLocks reassigns lock numbers for all containers and pods in the
// state. This should NOT be run while there are other Libpod
func (r *Runtime) RenumberLocks() error {
	// TODO: It would be desirable to make it impossible to call this until all
	// other libpod sessions are dead.
	// Possibly use a read-write file lock, with all non-renumber podmans owning the
	// lock as read, renumber attempting to take a write lock?
	// The alternative is some sort of session tracking, and I don't know how
	// reliable that can be.

	// Acquire the alive lock and hold it.
	// Ensures that we don't let other Podman commands run while we are
	// changing around lock numbers.
	aliveLock, err := r.getRuntimeAliveLock()
	if err != nil {
		return fmt.Errorf("retrieving alive lock: %w", err)
	}
	aliveLock.Lock()
	defer aliveLock.Unlock()

	if !r.valid {
		return define.ErrRuntimeStopped
	}

	// Start off by deallocating all locks
	if err := r.lockManager.FreeAllLocks(); err != nil {
		return err
	}

	allCtrs, err := r.state.AllContainers(false)
	if err != nil {
		return err
	}
	for _, ctr := range allCtrs {
		lock, err := r.lockManager.AllocateLock()
		if err != nil {
			return fmt.Errorf("allocating lock for container %s: %w", ctr.ID(), err)
		}

		ctr.config.LockID = lock.ID()

		// Write the new lock ID
		if err := r.state.RewriteContainerConfig(ctr, ctr.config); err != nil {
			return err
		}
	}
	allPods, err := r.state.AllPods()
	if err != nil {
		return err
	}
	for _, pod := range allPods {
		lock, err := r.lockManager.AllocateLock()
		if err != nil {
			return fmt.Errorf("allocating lock for pod %s: %w", pod.ID(), err)
		}

		pod.config.LockID = lock.ID()

		// Write the new lock ID
		if err := r.state.RewritePodConfig(pod, pod.config); err != nil {
			return err
		}
	}
	allVols, err := r.state.AllVolumes()
	if err != nil {
		return err
	}
	for _, vol := range allVols {
		lock, err := r.lockManager.AllocateLock()
		if err != nil {
			return fmt.Errorf("allocating lock for volume %s: %w", vol.Name(), err)
		}

		vol.config.LockID = lock.ID()

		// Write the new lock ID
		if err := r.state.RewriteVolumeConfig(vol, vol.config); err != nil {
			return err
		}
	}

	r.NewSystemEvent(events.Renumber)

	return r.Shutdown(false)
}