We take the fs_devices::device_list_mutex mutex in write_all_supers which will prevent any add/del changes to the device list. Therefore we don't need to use the RCU variant list_for_each_entry_rcu in any of the called functions.
Signed-off-by: David Sterba <[email protected]> --- fs/btrfs/disk-io.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index efce9a2fa9be..042cf46e4cd0 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -3396,9 +3396,10 @@ static int barrier_all_devices(struct btrfs_fs_info *info) int errors_wait = 0; blk_status_t ret; + WARN_ON(!mutex_is_locked(&info->fs_devices->device_list_mutex)); /* send down all the barriers */ head = &info->fs_devices->devices; - list_for_each_entry_rcu(dev, head, dev_list) { + list_for_each_entry(dev, head, dev_list) { if (dev->missing) continue; if (!dev->bdev) @@ -3411,7 +3412,7 @@ static int barrier_all_devices(struct btrfs_fs_info *info) } /* wait for all the barriers */ - list_for_each_entry_rcu(dev, head, dev_list) { + list_for_each_entry(dev, head, dev_list) { if (dev->missing) continue; if (!dev->bdev) { @@ -3510,7 +3511,7 @@ int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors) } } - list_for_each_entry_rcu(dev, head, dev_list) { + list_for_each_entry(dev, head, dev_list) { if (!dev->bdev) { total_errors++; continue; @@ -3551,7 +3552,7 @@ int write_all_supers(struct btrfs_fs_info *fs_info, int max_mirrors) } total_errors = 0; - list_for_each_entry_rcu(dev, head, dev_list) { + list_for_each_entry(dev, head, dev_list) { if (!dev->bdev) continue; if (!dev->in_fs_metadata || !dev->writeable) -- 2.14.0 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
