From: NeilBrown <neilb@suse.de>
Date: Fri, 13 Aug 2010 06:06:06 +0000 (+1000)
Subject: Fix lafs_put_super for subset mounts.
X-Git-Url: http://git.neil.brown.name/?a=commitdiff_plain;h=65881db00e268bc39b69e537f6c5ba2be3fe9000;p=LaFS.git

Fix lafs_put_super for subset mounts.

- we still need a checkpoint - though not a final one - to ensure
  that all dirty blocks from the fileset are written.

- We it isn't the root for a snapshot, we don't want to put
  to root inode - the root inode will be in the main filesystem,
  not in this one.

Signed-off-by: NeilBrown <neilb@suse.de>
---

diff --git a/super.c b/super.c
index 046d76f..5df896f 100644
--- a/super.c
+++ b/super.c
@@ -757,6 +757,14 @@ lafs_put_super(struct super_block *sb)
 	int ss;
 	struct lafs_inode *li;
 
+	lafs_checkpoint_lock(fs);
+	lafs_checkpoint_start(fs);
+	if (sb == fs->prime_sb)
+		/* Don't incorporate any more segusage/quota updates. */
+		set_bit(FinalCheckpoint, &fs->fsstate);
+	lafs_checkpoint_unlock_wait(fs);
+	lafs_cluster_wait_all(fs);
+
 	if (sb == fs->prime_sb) {
 		int d;
 		/* This is the main sb, not a snapshot or
@@ -764,12 +772,6 @@ lafs_put_super(struct super_block *sb)
 		 * Now that all inodes have been invalidated we can do
 		 * the final checkpoint.
 		 */
-		lafs_checkpoint_lock(fs);
-		/* Don't incorporate any more segusage/quota updates. */
-		lafs_checkpoint_start(fs);
-		set_bit(FinalCheckpoint, &fs->fsstate);
-		lafs_checkpoint_unlock_wait(fs);
-		lafs_cluster_wait_all(fs);
 		lafs_close_all_segments(fs);
 		lafs_empty_segment_table(fs);
 		lafs_seg_put_all(fs);
@@ -786,14 +788,15 @@ lafs_put_super(struct super_block *sb)
 	/* need to break a circular reference... */
 	for (ss = 0; ss < fs->maxsnapshot; ss++)
 		if (fs->ss[ss].root &&
-		    fs->ss[ss].root->i_sb == sb)
+		    fs->ss[ss].root->i_sb == sb) {
+			dprintk("Putting ss %d\n", ss);
+			li = LAFSI(fs->ss[ss].root);
+			if (test_bit(B_Realloc, &li->dblock->b.flags))
+				lafs_dump_tree();
+			iput(fs->ss[ss].root);
+			fs->ss[ss].root = NULL;
 			break;
-	dprintk("Putting ss %d\n", ss);
-	li = LAFSI(fs->ss[ss].root);
-	if (test_bit(B_Realloc, &li->dblock->b.flags))
-		lafs_dump_tree();
-	iput(fs->ss[ss].root);
-	fs->ss[ss].root = NULL;
+		}
 }
 
 static int