[PATCH 07/13] btrfs: reduce scope of data_stripes in btrfs_map_block

Johannes Thumshirn
2023-12-12T12:38:59Z

Reduce the scope of 'data_stripes' in btrfs_map_block(). While the change
allone doesn't make too much sense, it helps us factoring out a helper
function for the block mapping of RAID56 I/O.

Signed-off-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
---
fs/btrfs/volumes.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 9090bfc4fe38..bc0988d8bd56 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -6480,7 +6480,6 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
struct btrfs_chunk_map *map;
struct btrfs_io_geometry io_geom = { };
u64 map_offset;
- int data_stripes;
int i;
int ret = 0;
int num_copies;
@@ -6500,8 +6499,6 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
if (IS_ERR(map))
return PTR_ERR(map);

- data_stripes = nr_data_stripes(map);
-
map_offset = logical - map->start;
io_geom.raid56_full_stripe_start = (u64)-1;
max_len = btrfs_max_io_len(map, op, map_offset, &io_geom.stripe_nr,
@@ -6532,6 +6529,8 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
map_blocks_for_raid10(fs_info, map, op, &io_geom,
dev_replace_is_ongoing);
} else if (map->type & BTRFS_BLOCK_GROUP_RAID56_MASK) {
+ int data_stripes = nr_data_stripes(map);
+
if (op != BTRFS_MAP_READ || io_geom.mirror_num > 1) {
/*
* Needs full stripe mapping.
@@ -6643,7 +6642,8 @@ int btrfs_map_block(struct btrfs_fs_info *fs_info, enum btrfs_map_op op,
* modulo, to reduce one modulo call.
*/
bioc->full_stripe_logical = map->start +
- btrfs_stripe_nr_to_offset(io_geom.stripe_nr * data_stripes);
+ btrfs_stripe_nr_to_offset(io_geom.stripe_nr *
+ nr_data_stripes(map));
for (int i = 0; i < io_geom.num_stripes; i++) {
ret = set_io_stripe(fs_info, op, logical, length,
&bioc->stripes[i], map,

--
2.43.0