github.com/jiasir/docker@v1.3.3-0.20170609024000-252e610103e7/daemon/daemon_linux.go (about)

     1  package daemon
     2  
     3  import (
     4  	"bufio"
     5  	"fmt"
     6  	"io"
     7  	"os"
     8  	"regexp"
     9  	"strings"
    10  
    11  	"github.com/Sirupsen/logrus"
    12  	"github.com/docker/docker/pkg/mount"
    13  )
    14  
    15  // On Linux, plugins use a static path for storing execution state,
    16  // instead of deriving path from daemon's exec-root. This is because
    17  // plugin socket files are created here and they cannot exceed max
    18  // path length of 108 bytes.
    19  func getPluginExecRoot(root string) string {
    20  	return "/run/docker/plugins"
    21  }
    22  
    23  func (daemon *Daemon) cleanupMountsByID(id string) error {
    24  	logrus.Debugf("Cleaning up old mountid %s: start.", id)
    25  	f, err := os.Open("/proc/self/mountinfo")
    26  	if err != nil {
    27  		return err
    28  	}
    29  	defer f.Close()
    30  
    31  	return daemon.cleanupMountsFromReaderByID(f, id, mount.Unmount)
    32  }
    33  
    34  func (daemon *Daemon) cleanupMountsFromReaderByID(reader io.Reader, id string, unmount func(target string) error) error {
    35  	if daemon.root == "" {
    36  		return nil
    37  	}
    38  	var errors []string
    39  
    40  	regexps := getCleanPatterns(id)
    41  	sc := bufio.NewScanner(reader)
    42  	for sc.Scan() {
    43  		if fields := strings.Fields(sc.Text()); len(fields) >= 4 {
    44  			if mnt := fields[4]; strings.HasPrefix(mnt, daemon.root) {
    45  				for _, p := range regexps {
    46  					if p.MatchString(mnt) {
    47  						if err := unmount(mnt); err != nil {
    48  							logrus.Error(err)
    49  							errors = append(errors, err.Error())
    50  						}
    51  					}
    52  				}
    53  			}
    54  		}
    55  	}
    56  
    57  	if err := sc.Err(); err != nil {
    58  		return err
    59  	}
    60  
    61  	if len(errors) > 0 {
    62  		return fmt.Errorf("Error cleaning up mounts:\n%v", strings.Join(errors, "\n"))
    63  	}
    64  
    65  	logrus.Debugf("Cleaning up old mountid %v: done.", id)
    66  	return nil
    67  }
    68  
    69  // cleanupMounts umounts shm/mqueue mounts for old containers
    70  func (daemon *Daemon) cleanupMounts() error {
    71  	return daemon.cleanupMountsByID("")
    72  }
    73  
    74  func getCleanPatterns(id string) (regexps []*regexp.Regexp) {
    75  	var patterns []string
    76  	if id == "" {
    77  		id = "[0-9a-f]{64}"
    78  		patterns = append(patterns, "containers/"+id+"/shm")
    79  	}
    80  	patterns = append(patterns, "aufs/mnt/"+id+"$", "overlay/"+id+"/merged$", "zfs/graph/"+id+"$")
    81  	for _, p := range patterns {
    82  		r, err := regexp.Compile(p)
    83  		if err == nil {
    84  			regexps = append(regexps, r)
    85  		}
    86  	}
    87  	return
    88  }