btrfs: Streamline replace sem unlock in btrfs_dev_replace_start

There are only 2 branches which goto leave label with need_unlock set
to true. Essentially need_unlock is used as a substitute for directly
calling up_write. Since the branches needing this are only 2 and their
context is not that big it's more clear to just call up_write where
required. No functional changes.

Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/dev-replace.c b/fs/btrfs/dev-replace.c
index 149e613..94f000b 100644 (file)
--- a/fs/btrfs/dev-replace.c
+++ b/fs/btrfs/dev-replace.c
@@ -400,7 +400,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        int ret;
        struct btrfs_device *tgt_device = NULL;
        struct btrfs_device *src_device = NULL;
-       bool need_unlock;
 
        src_device = btrfs_find_device_by_devspec(fs_info, srcdevid,
                                                  srcdev_name);
@@ -432,7 +431,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        if (ret)
                return ret;
 
-       need_unlock = true;
        down_write(&dev_replace->rwsem);
        switch (dev_replace->replace_state) {
        case BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED:
@@ -443,6 +441,7 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        case BTRFS_IOCTL_DEV_REPLACE_STATE_SUSPENDED:
                ASSERT(0);
                ret = BTRFS_IOCTL_DEV_REPLACE_RESULT_ALREADY_STARTED;
+               up_write(&dev_replace->rwsem);
                goto leave;
        }
 
@@ -471,7 +470,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        atomic64_set(&dev_replace->num_write_errors, 0);
        atomic64_set(&dev_replace->num_uncorrectable_read_errors, 0);
        up_write(&dev_replace->rwsem);
-       need_unlock = false;
 
        ret = btrfs_sysfs_add_device_link(tgt_device->fs_devices, tgt_device);
        if (ret)
@@ -483,12 +481,12 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        trans = btrfs_start_transaction(root, 0);
        if (IS_ERR(trans)) {
                ret = PTR_ERR(trans);
-               need_unlock = true;
                down_write(&dev_replace->rwsem);
                dev_replace->replace_state =
                        BTRFS_IOCTL_DEV_REPLACE_STATE_NEVER_STARTED;
                dev_replace->srcdev = NULL;
                dev_replace->tgtdev = NULL;
+               up_write(&dev_replace->rwsem);
                goto leave;
        }
 
@@ -510,8 +508,6 @@ static int btrfs_dev_replace_start(struct btrfs_fs_info *fs_info,
        return ret;
 
 leave:
-       if (need_unlock)
-               up_write(&dev_replace->rwsem);
        btrfs_destroy_dev_replace_tgtdev(tgt_device);
        return ret;
 }