Commit f1ed785a authored by Filipe Manana's avatar Filipe Manana Committed by David Sterba
Browse files

btrfs: use a single switch statement when initializing delayed ref head 



At init_delayed_ref_head(), we are using two separate if statements to
check the delayed ref head action, and initializing 'must_insert_reserved'
to false twice, once when the variable is declared and once again in an
else branch.

Make this simpler and more straightforward by having a single switch
statement, also moving the comment about a drop action to the
corresponding switch case to make it more clear and eliminating the
duplicated initialization of 'must_insert_reserved' to false.

Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 61c681fe

fs/btrfs/delayed-ref.c

+24 −20
Original line number Diff line number Diff line
@@ -702,29 +702,33 @@ static void init_delayed_ref_head(struct btrfs_delayed_ref_head *head_ref, 
	/* If reserved is provided, it must be a data extent. */

	BUG_ON(!is_data && reserved);



	switch (action) {

	case BTRFS_UPDATE_DELAYED_HEAD:

		count_mod = 0;

		break;

	case BTRFS_DROP_DELAYED_REF:

		/*

		 * The head node stores the sum of all the mods, so dropping a ref

		 * should drop the sum in the head node by one.

		 */

	if (action == BTRFS_UPDATE_DELAYED_HEAD)

		count_mod = 0;

	else if (action == BTRFS_DROP_DELAYED_REF)

		count_mod = -1;



		break;

	case BTRFS_ADD_DELAYED_EXTENT:

		/*

	 * BTRFS_ADD_DELAYED_EXTENT means that we need to update the reserved

	 * accounting when the extent is finally added, or if a later

	 * modification deletes the delayed ref without ever inserting the

	 * extent into the extent allocation tree.  ref->must_insert_reserved

	 * is the flag used to record that accounting mods are required.

		 * BTRFS_ADD_DELAYED_EXTENT means that we need to update the

		 * reserved accounting when the extent is finally added, or if a

		 * later modification deletes the delayed ref without ever

		 * inserting the extent into the extent allocation tree.

		 * ref->must_insert_reserved is the flag used to record that

		 * accounting mods are required.

		 *

		 * Once we record must_insert_reserved, switch the action to

	 * BTRFS_ADD_DELAYED_REF because other special casing is not required.

		 * BTRFS_ADD_DELAYED_REF because other special casing is not

		 * required.

		 */

	if (action == BTRFS_ADD_DELAYED_EXTENT)

		must_insert_reserved = true;

	else

		must_insert_reserved = false;

		break;

	}



	refcount_set(&head_ref->refs, 1);

	head_ref->bytenr = bytenr;