src/slave/containerizer/mesos/isolators/filesystem/linux.hpp

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// to you under the Apache License, Version 2.0 (the
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//
//     http://www.apache.org/licenses/LICENSE-2.0
//
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#ifndef __LINUX_FILESYSTEM_ISOLATOR_HPP__
#define __LINUX_FILESYSTEM_ISOLATOR_HPP__

#include <mesos/mesos.hpp>
#include <mesos/resources.hpp>

#include <process/owned.hpp>
#include <process/pid.hpp>

#include <process/metrics/pull_gauge.hpp>

#include <stout/hashmap.hpp>

#include "slave/flags.hpp"

#include "slave/containerizer/mesos/isolator.hpp"

#include "slave/volume_gid_manager/volume_gid_manager.hpp"

namespace mesos {
namespace internal {
namespace slave {

// The filesystem isolator on Linux that is responsible for preparing
// the root filesystems and volumes (e.g., persistent volumes) for
// containers. It relies on Linux mount namespace to prevent mounts of
// a container from being propagated to the host mount table.
class LinuxFilesystemIsolatorProcess : public MesosIsolatorProcess
{
public:
  static Try<mesos::slave::Isolator*> create(
      const Flags& flags,
      VolumeGidManager* volumeGidManager = nullptr);

  ~LinuxFilesystemIsolatorProcess() override;

  bool supportsNesting() override;
  bool supportsStandalone() override;

  process::Future<Nothing> recover(
      const std::vector<mesos::slave::ContainerState>& states,
      const hashset<ContainerID>& orphans) override;

  process::Future<Option<mesos::slave::ContainerLaunchInfo>> prepare(
      const ContainerID& containerId,
      const mesos::slave::ContainerConfig& containerConfig) override;

  process::Future<Nothing> update(
      const ContainerID& containerId,
      const Resources& resourceRequests,
      const google::protobuf::Map<
          std::string, Value::Scalar>& resourceLimits = {}) override;

  process::Future<Nothing> cleanup(
      const ContainerID& containerId) override;

private:
  LinuxFilesystemIsolatorProcess(
      const Flags& flags,
      VolumeGidManager* volumeGidManager);

  const Flags flags;
  VolumeGidManager* volumeGidManager;

  struct Info
  {
    Info(const std::string& _directory) : directory(_directory) {}

    Info(const std::string& _directory,
         const Option<ExecutorInfo>& _executor)
      : directory(_directory),
        executor(_executor) {}

    const std::string directory;

    // Track resources so we can unmount unneeded persistent volumes.
    Resources resources;

    Option<ExecutorInfo> executor;
    std::vector<gid_t> gids;
  };

  hashmap<ContainerID, process::Owned<Info>> infos;

  struct Metrics
  {
    explicit Metrics(
        const process::PID<LinuxFilesystemIsolatorProcess>& isolator);
    ~Metrics();

    process::metrics::PullGauge containers_new_rootfs;
  } metrics;

  double _containers_new_rootfs();
};

} // namespace slave {
} // namespace internal {
} // namespace mesos {

#endif // __LINUX_FILESYSTEM_ISOLATOR_HPP__