diff options
Diffstat (limited to 'fs/btrfs/volumes.c')
| -rw-r--r-- | fs/btrfs/volumes.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 298e5885ed06..8355533fd287 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -4722,6 +4722,7 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) u64 old_size = btrfs_device_get_total_bytes(device); u64 diff; u64 start; + u64 free_diff = 0; new_size = round_down(new_size, fs_info->sectorsize); start = new_size; @@ -4747,7 +4748,19 @@ int btrfs_shrink_device(struct btrfs_device *device, u64 new_size) btrfs_device_set_total_bytes(device, new_size); if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { device->fs_devices->total_rw_bytes -= diff; - atomic64_sub(diff, &fs_info->free_chunk_space); + + /* + * The new free_chunk_space is new_size - used, so we have to + * subtract the delta of the old free_chunk_space which included + * old_size - used. If used > new_size then just subtract this + * entire device's free space. + */ + if (device->bytes_used < new_size) + free_diff = (old_size - device->bytes_used) - + (new_size - device->bytes_used); + else + free_diff = old_size - device->bytes_used; + atomic64_sub(free_diff, &fs_info->free_chunk_space); } /* @@ -4882,9 +4895,10 @@ done: if (ret) { mutex_lock(&fs_info->chunk_mutex); btrfs_device_set_total_bytes(device, old_size); - if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) + if (test_bit(BTRFS_DEV_STATE_WRITEABLE, &device->dev_state)) { device->fs_devices->total_rw_bytes += diff; - atomic64_add(diff, &fs_info->free_chunk_space); + atomic64_add(free_diff, &fs_info->free_chunk_space); + } mutex_unlock(&fs_info->chunk_mutex); } return ret; |