From: David Sterba <dsterba@suse.com>
Date: Wed, 27 May 2026 11:16:52 +0000 (+0200)
Subject: btrfs: use shifts for sectorsize and nodesize
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=422ccdfe22c26c72246ca8ca1f90524be95055ef;p=thirdparty%2Flinux.git

btrfs: use shifts for sectorsize and nodesize

Convert more multiplications of sectorsize or nodesize to use the
shifts. The remaining cases are multiplications by constants that
compiler can optimize by itself, and in tests.

Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: David Sterba <dsterba@suse.com>
---

diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index 4293a63834337..d357ed7efd99b 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -281,7 +281,7 @@ static void btrfs_calculate_inode_block_rsv_size(struct btrfs_fs_info *fs_info,
 	 *
 	 * This is overestimating in most cases.
 	 */
-	qgroup_rsv_size = (u64)outstanding_extents * fs_info->nodesize;
+	qgroup_rsv_size = ((u64)outstanding_extents << fs_info->nodesize_bits);
 
 	spin_lock(&block_rsv->lock);
 	block_rsv->size = reserve_size;
@@ -311,7 +311,7 @@ static void calc_inode_reservations(struct btrfs_inode *inode,
 	 * for an inode update.
 	 */
 	*meta_reserve += inode_update;
-	*qgroup_reserve = nr_extents * fs_info->nodesize;
+	*qgroup_reserve = (nr_extents << fs_info->nodesize_bits);
 }
 
 int btrfs_delalloc_reserve_metadata(struct btrfs_inode *inode, u64 num_bytes,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index ec13eac2b3d7b..531e0a68f06b3 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -563,7 +563,7 @@ static bool btree_dirty_folio(struct address_space *mapping,
 			continue;
 		}
 		spin_unlock_irqrestore(&subpage->lock, flags);
-		cur = page_start + cur_bit * fs_info->sectorsize;
+		cur = page_start + (cur_bit << fs_info->sectorsize_bits);
 
 		eb = find_extent_buffer(fs_info, cur);
 		ASSERT(eb);
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index 82ae4a2afd347..9f6454e9db818 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -1309,7 +1309,7 @@ found:
 
 	index += ins_size;
 	ins_size /= csum_size;
-	total_bytes += ins_size * fs_info->sectorsize;
+	total_bytes += (ins_size << fs_info->sectorsize_bits);
 
 	if (total_bytes < sums->len) {
 		btrfs_release_path(path);
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 2b11eda49c06e..9469f89823550 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -1574,7 +1574,7 @@ static noinline_for_stack int merge_reloc_root(struct reloc_control *rc,
 	 * and * 2 since we have two trees to COW.
 	 */
 	reserve_level = max_t(int, 1, btrfs_root_level(root_item));
-	min_reserved = fs_info->nodesize * reserve_level * 2;
+	min_reserved = (reserve_level << fs_info->nodesize_bits) * 2;
 	memset(&next_key, 0, sizeof(next_key));
 
 	while (1) {
@@ -2572,7 +2572,7 @@ static int relocate_cowonly_block(struct btrfs_trans_handle *trans,
 
 	nr_levels = max(btrfs_header_level(root->node) - block->level, 0) + 1;
 
-	num_bytes = fs_info->nodesize * nr_levels;
+	num_bytes = (nr_levels << fs_info->nodesize_bits);
 	ret = refill_metadata_space(trans, rc, num_bytes);
 	if (ret) {
 		btrfs_put_root(root);
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index a289a8fa237c8..2263cb6bd8ca4 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -631,7 +631,7 @@ start_transaction(struct btrfs_root *root, unsigned int num_items,
 	 * the appropriate flushing if need be.
 	 */
 	if (num_items && root != fs_info->chunk_root) {
-		qgroup_reserved = num_items * fs_info->nodesize;
+		qgroup_reserved = (num_items << fs_info->nodesize_bits);
 		/*
 		 * Use prealloc for now, as there might be a currently running
 		 * transaction that could free this reserved space prematurely