Commit 946c9256 authored by David Sterba's avatar David Sterba
Browse files

btrfs: factor out helper for counting data stripes 



Factor the sequence of ifs to a helper, the 'data stripes' here means
the number of stripes without redundancy and parity.

Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 44b28ada

fs/btrfs/volumes.c

+15 −10
Original line number Diff line number Diff line
@@ -3474,6 +3474,18 @@ static int chunk_devid_filter(struct extent_buffer *leaf, 
	return 1;

}



static u64 calc_data_stripes(u64 type, int num_stripes)

{

	const int index = btrfs_bg_flags_to_raid_index(type);

	const int ncopies = btrfs_raid_array[index].ncopies;

	const int nparity = btrfs_raid_array[index].nparity;



	if (nparity)

		return num_stripes - nparity;

	else

		return num_stripes / ncopies;

}



/* [pstart, pend) */

static int chunk_drange_filter(struct extent_buffer *leaf,

			       struct btrfs_chunk *chunk,
@@ -3483,22 +3495,15 @@ static int chunk_drange_filter(struct extent_buffer *leaf, 
	int num_stripes = btrfs_chunk_num_stripes(leaf, chunk);

	u64 stripe_offset;

	u64 stripe_length;

	u64 type;

	int factor;

	int i;



	if (!(bargs->flags & BTRFS_BALANCE_ARGS_DEVID))

		return 0;



	if (btrfs_chunk_type(leaf, chunk) & (BTRFS_BLOCK_GROUP_DUP |

	     BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10)) {

		factor = num_stripes / 2;

	} else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID5) {

		factor = num_stripes - 1;

	} else if (btrfs_chunk_type(leaf, chunk) & BTRFS_BLOCK_GROUP_RAID6) {

		factor = num_stripes - 2;

	} else {

		factor = num_stripes;

	}

	type = btrfs_chunk_type(leaf, chunk);

	factor = calc_data_stripes(type, num_stripes);



	for (i = 0; i < num_stripes; i++) {

		stripe = btrfs_stripe_nr(chunk, i);