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Revert "btrfs: let btrfs_delete_unused_bgs() to clean relocated bgs"

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This reverts commit 5d8eb6fe51.

When we remove devices, we free the device structures.  Delaying
btfs_remove_chunk() ends up hitting a use-after-free on them.

Signed-off-by: Chris Mason <clm@fb.com>
This commit is contained in:
Chris Mason 2016-10-10 13:43:31 -07:00
parent 196e02490c
commit 19c4d2f994
2 changed files with 16 additions and 12 deletions
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2
fs/btrfs/extent-tree.c
View file

@ -10849,7 +10849,7 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
spin_lock(&block_group->lock);
if (block_group->reserved ||
btrfs_block_group_used(&block_group->item) ||
(block_group->ro && !block_group->removed) ||
block_group->ro ||
list_is_singular(&block_group->list)) {
/*
* We want to bail if we made new allocations or have

26
fs/btrfs/volumes.c
View file

@ -2906,8 +2906,8 @@ int btrfs_remove_chunk(struct btrfs_trans_handle *trans,
static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
{
struct btrfs_root *extent_root;
struct btrfs_trans_handle *trans;
int ret;
struct btrfs_block_group_cache *block_group;
root = root->fs_info->chunk_root;
extent_root = root->fs_info->extent_root;
@ -2937,17 +2937,21 @@ static int btrfs_relocate_chunk(struct btrfs_root *root, u64 chunk_offset)
if (ret)
return ret;
/*
* step two, flag the chunk as removed and let
* btrfs_delete_unused_bgs() remove it.
*/
block_group = btrfs_lookup_block_group(root->fs_info, chunk_offset);
spin_lock(&block_group->lock);
block_group->removed = 1;
spin_unlock(&block_group->lock);
btrfs_put_block_group(block_group);
trans = btrfs_start_trans_remove_block_group(root->fs_info,
chunk_offset);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
btrfs_handle_fs_error(root->fs_info, ret, NULL);
return ret;
}
return 0;
/*
* step two, delete the device extents and the
* chunk tree entries
*/
ret = btrfs_remove_chunk(trans, root, chunk_offset);
btrfs_end_transaction(trans, extent_root);
return ret;
}
static int btrfs_relocate_sys_chunks(struct btrfs_root *root)