Add .zfs control directory

[zfs.git] / module / zfs / zpl_super.c

diff --git a/module/zfs/zpl_super.c b/module/zfs/zpl_super.c
index 0e6e936..98d0a03 100644 (file)
--- a/module/zfs/zpl_super.c
+++ b/module/zfs/zpl_super.c
@@ -26,6 +26,7 @@
 #include <sys/zfs_vfsops.h>
 #include <sys/zfs_vnops.h>
 #include <sys/zfs_znode.h>
+#include <sys/zfs_ctldir.h>
 #include <sys/zpl.h>
 
 
@@ -139,6 +140,20 @@ zpl_remount_fs(struct super_block *sb, int *flags, char *data)
        return (error);
 }
 
+static void
+zpl_umount_begin(struct super_block *sb)
+{
+       zfs_sb_t *zsb = sb->s_fs_info;
+       int count;
+
+       /*
+        * Best effort to unmount snapshots in .zfs/snapshot/.  Normally this
+        * isn't required because snapshots have the MNT_SHRINKABLE flag set.
+        */
+       if (zsb->z_ctldir)
+               (void) zfsctl_unmount_snapshots(zsb, MNT_FORCE, &count);
+}
+
 /*
  * The Linux VFS automatically handles the following flags:
  * MNT_NOSUID, MNT_NODEV, MNT_NOEXEC, MNT_NOATIME, MNT_READONLY
@@ -199,13 +214,7 @@ zpl_get_sb(struct file_system_type *fs_type, int flags,
 static void
 zpl_kill_sb(struct super_block *sb)
 {
-#ifdef HAVE_SNAPSHOT
-       zfs_sb_t *zsb = sb->s_fs_info;
-
-       if (zsb && dmu_objset_is_snapshot(zsb->z_os))
-               zfs_snap_destroy(zsb);
-#endif /* HAVE_SNAPSHOT */
-
+       zfs_preumount(sb);
        kill_anon_super(sb);
 }
 
@@ -306,6 +315,7 @@ const struct super_operations zpl_super_operations = {
        .sync_fs                = zpl_sync_fs,
        .statfs                 = zpl_statfs,
        .remount_fs             = zpl_remount_fs,
+       .umount_begin           = zpl_umount_begin,
        .show_options           = zpl_show_options,
        .show_stats             = NULL,
 #ifdef HAVE_NR_CACHED_OBJECTS