mm/swap: Fix swap_cluster_lock() !CONFIG_SWAP stub signature mismatch

From: Hongfu Li <[email protected]>

The !CONFIG_SWAP stub for swap_cluster_lock() has mismatched prototype:
it has an extra unused irq argument and uses pgoff_t instead of unsigned long for offset. All callers are under CONFIG_SWAP so the extra parameter is dead.

Delete the unused stub function entirely.

Signed-off-by Hongfu Li <[email protected]>

Reviewed-by Baoquan He <[email protected]>

---
v2:
- Drop the stub entirely instead of fixing its signature. All callers are under CONFIG_SWAP, so the stub is dead code. (Suggested by Kairui Song)
- Add Reviewed-by tag
- Update commit message

---
 mm/swap.h | 6 ------
 1 file changed, 6 deletions(-)

mm/swap.h +0 -7

index 77d2d14eda42..d7834888e0d2 100644
@@ -336,12 +336,6 @@ static inline unsigned int folio_swap_flags(struct folio *folio)
 
 #else /* CONFIG_SWAP */
 struct swap_iocb;
-static inline struct swap_cluster_info *swap_cluster_lock(
-       struct swap_info_struct *si, pgoff_t offset, bool irq)
-{
-       return NULL;
-}
-
 static inline struct swap_cluster_info *swap_cluster_get_and_lock(
                struct folio *folio)
 {
--

2.54.0