[PATCH 03/13] btrfs: factor out block-mapping for RAID0

Johannes Thumshirn
2023-12-12T12:38:31Z

Now that we have a container for the I/O geometry that has all the needed
information for the block mappings of RAID0, factor out a helper calculating
this information.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
fs/btrfs/volumes.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index d0e529b3fd39..a5d85a77da25 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6362,6 +6362,16 @@ static bool is_single_device_io(struct btrfs_fs_info *fs_info,
return true;
}

+static void map_blocks_for_raid0(struct btrfs_chunk_map *map,
+ enum btrfs_map_op op,
+ struct btrfs_io_geometry *io_geom)
+{
+ io_geom->stripe_index = io_geom->stripe_nr % map->num_stripes;
+ io_geom->stripe_nr /= map->num_stripes;
+ if (op == BTRFS_MAP_READ)
+ io_geom->mirror_num = 1;
+}
+
/*
* Map one logical range to one or more physical ranges.
*
@@ -6447,10 +6457,7 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
io_geom.stripe_index = 0;
io_geom.mirror_num = (mirror_num_ret ? *mirror_num_ret : 0);
if (map->type & BTRFS_BLOCK_GROUP_RAID0) {
- io_geom.stripe_index = io_geom.stripe_nr % map->num_stripes;
- io_geom.stripe_nr /= map->num_stripes;
- if (op == BTRFS_MAP_READ)
- io_geom.mirror_num = 1;
+ map_blocks_for_raid0(map, op, &io_geom);
} else if (map->type & BTRFS_BLOCK_GROUP_RAID1_MASK) {
if (op != BTRFS_MAP_READ) {
io_geom.num_stripes = map->num_stripes;

--
2.43.0