[PATCH 11/20] Btrfs: note when a bitmap is skipped because its list is in use

[Alexandre Oliva <oliva@lsd.ic.unicamp.br>]

Bitmap lists serve two purposes: recording the order of loading/saving
on-disk free space caches, and setting up a list of bitmaps to try to
set up a cluster.  Complain if a list is unexpectedly busy.

Signed-off-by: Alexandre Oliva <oliva@lsd.ic.unicamp.br>
---
 fs/btrfs/free-space-cache.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)

diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index ec23d43..dd7fe43 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -904,6 +904,7 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
 			goto out_nospc;
 
 		if (e->bitmap) {
+			BUG_ON(!list_empty(&e->list));
 			list_add_tail(&e->list, &bitmap_list);
 			bitmaps++;
 		}
@@ -2380,6 +2381,9 @@ setup_cluster_no_bitmap(struct btrfs_block_group_cache *block_group,
 	while (entry->bitmap) {
 		if (list_empty(&entry->list))
 			list_add_tail(&entry->list, bitmaps);
+		else if (entry->bitmap)
+			printk(KERN_ERR "btrfs: not using (busy?!?) bitmap %lli\n",
+			       (unsigned long long)entry->offset);
 		node = rb_next(&entry->offset_index);
 		if (!node)
 			return -ENOSPC;
@@ -2402,6 +2406,9 @@ setup_cluster_no_bitmap(struct btrfs_block_group_cache *block_group,
 		if (entry->bitmap) {
 			if (list_empty(&entry->list))
 				list_add_tail(&entry->list, bitmaps);
+			else
+				printk(KERN_ERR "btrfs: not using (busy?!?) bitmap %lli\n",
+				       (unsigned long long)entry->offset);
 			continue;
 		}
 
-- 
1.7.4.4