clean up the loop devices not released

the pidfiles record last running info of device and
process pid, and now mic can clean these up if they
are not released for some unknown reason

Change-Id: I3b0bbd31fbcfaf7fe4c751feab6f7f9b528d64f6
Signed-off-by: Gui Chen <gui.chen@intel.com>

diff --git a/mic/utils/fs_related.py b/mic/utils/fs_related.py
index 7614132..7c4b538 100644 (file)
--- a/mic/utils/fs_related.py
+++ b/mic/utils/fs_related.py
@@ -948,6 +948,10 @@ def get_loop_device(losetupcmd, lofile):
         loopdev = None
         devinst = LoopDevice()
 
+        # clean up left loop device first
+        clean_loop_devices()
+
+        # provide an avaible loop device
         rc, out = runner.runtool([losetupcmd, "--find"])
         if rc == 0:
             loopdev = out.split()[0]
@@ -956,6 +960,7 @@ def get_loop_device(losetupcmd, lofile):
             devinst.create()
             loopdev = devinst.device
 
+        # setup a loop device for image file
         rc = runner.show([losetupcmd, loopdev, lofile])
         if rc != 0:
             raise MountError("Failed to setup loop device for '%s'" % lofile)
@@ -984,3 +989,28 @@ def get_loop_device(losetupcmd, lofile):
 
     return loopdev
 
+def clean_loop_devices(piddir=DEVICE_PIDFILE_DIR):
+    if not os.path.exists(piddir) or not os.path.isdir(piddir):
+        return
+
+    for loopdev in os.listdir(piddir):
+        pidfile = os.path.join(piddir, loopdev)
+        try:
+            with open(pidfile, 'r') as rf:
+                devpid = int(rf.read())
+        except:
+            devpid = None
+
+        # if the process using this device is alive, skip it
+        if not devpid or os.path.exists(os.path.join('/proc', str(devpid))):
+            continue
+
+        # try to clean it up
+        try:
+            devinst = LoopDevice()
+            devinst.register(os.path.join('/dev', loopdev))
+            devinst.cleanup()
+            os.unlink(pidfile)
+        except:
+            pass
+