loop: cleanup partitions when detaching loop device
authorPhillip Susi <psusi@ubuntu.com>
Fri, 22 Mar 2013 18:21:53 +0000 (12:21 -0600)
committerJens Axboe <axboe@kernel.dk>
Fri, 22 Mar 2013 18:21:53 +0000 (12:21 -0600)
Any partitions added by user space to the loop device were being
left in place after detaching the loop device.  This was because
the detach path issued a BLKRRPART to clean up partitions if
LO_FLAGS_PARTSCAN was set, meaning that the partitions were auto
scanned on attach.  Replace this BLKRRPART with code that
unconditionally cleans up partitions on detach instead.

Signed-off-by: Phillip Susi <psusi@ubuntu.com>
Modified by Jens to export delete_partition().

Signed-off-by: Jens Axboe <axboe@kernel.dk>
block/partition-generic.c
drivers/block/loop.c

index 789cdea..ae95ee6 100644 (file)
@@ -257,6 +257,7 @@ void delete_partition(struct gendisk *disk, int partno)
 
        hd_struct_put(part);
 }
+EXPORT_SYMBOL(delete_partition);
 
 static ssize_t whole_disk_show(struct device *dev,
                               struct device_attribute *attr, char *buf)
index ee13a82..fe5f640 100644 (file)
@@ -1044,12 +1044,29 @@ static int loop_clr_fd(struct loop_device *lo)
        lo->lo_state = Lo_unbound;
        /* This is safe: open() is still holding a reference. */
        module_put(THIS_MODULE);
-       if (lo->lo_flags & LO_FLAGS_PARTSCAN && bdev)
-               ioctl_by_bdev(bdev, BLKRRPART, 0);
        lo->lo_flags = 0;
        if (!part_shift)
                lo->lo_disk->flags |= GENHD_FL_NO_PART_SCAN;
        mutex_unlock(&lo->lo_ctl_mutex);
+
+       /*
+        * Remove all partitions, since BLKRRPART won't remove user
+        * added partitions when max_part=0
+        */
+       if (bdev) {
+               struct disk_part_iter piter;
+               struct hd_struct *part;
+
+               mutex_lock_nested(&bdev->bd_mutex, 1);
+               invalidate_partition(bdev->bd_disk, 0);
+               disk_part_iter_init(&piter, bdev->bd_disk,
+                                       DISK_PITER_INCL_EMPTY);
+               while ((part = disk_part_iter_next(&piter)))
+                       delete_partition(bdev->bd_disk, part->partno);
+               disk_part_iter_exit(&piter);
+               mutex_unlock(&bdev->bd_mutex);
+       }
+
        /*
         * Need not hold lo_ctl_mutex to fput backing file.
         * Calling fput holding lo_ctl_mutex triggers a circular