ARC: Fix CONFIG_SWAP

swap was broken on ARC due to silly copy-paste issue. We encode offset from swapcache page in __swp_entry() as (off << 13) but were not decoding back in __swp_offset() as (off >> 13) - it was still (off << 13). This finally fixes swap usage on ARC. | # mkswap /dev/sda2 | | # swapon -a -e /dev/sda2 | Adding 500728k swap on /dev/sda2. Priority:-2 extents:1 across:500728k | | # free | total used free shared buffers cached | Mem: 765104 13456 751648 4736 8 4736 | -/+ buffers/cache: 8712 756392 | Swap: 500728 0 500728 Cc: [email protected] Signed-off-by: Alexey Brodkin <[email protected]> Signed-off-by: Vineet Gupta <[email protected]>
olifre · Jul 9, 2018 · 6e37611 · 6e37611
1 parent ca1147f
commit 6e37611
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/arch/arc/include/asm/pgtable.h b/arch/arc/include/asm/pgtable.h
@@ -379,7 +379,7 @@ void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
 
 /* Decode a PTE containing swap "identifier "into constituents */
 #define __swp_type(pte_lookalike)	(((pte_lookalike).val) & 0x1f)
-#define __swp_offset(pte_lookalike)	((pte_lookalike).val << 13)
+#define __swp_offset(pte_lookalike)	((pte_lookalike).val >> 13)
 
 /* NOPs, to keep generic kernel happy */
 #define __pte_to_swp_entry(pte)	((swp_entry_t) { pte_val(pte) })