f2fs: refresh recent accessed nat entry in lru list

From: Chao Yu <[email protected]>

Introduce nat_list_lock to protect nm_i->nat_entries list, and manage it as a LRU list, refresh location for therein recent accessed entries in the list.

---
 fs/f2fs/f2fs.h |  1 +
 fs/f2fs/node.c | 46 ++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 43 insertions(+), 4 deletions(-)

index f4b03339799e..afcdba241c4b 100644
@@ -780,6 +780,7 @@ struct f2fs_nm_info {
 	struct radix_tree_root nat_set_root;/* root of the nat set cache */
 	struct rw_semaphore nat_tree_lock;	/* protect nat_tree_lock */
 	struct list_head nat_entries;	/* cached nat entry list (clean) */
+	spinlock_t nat_list_lock;	/* protect clean nat entry list */
 	unsigned int nat_cnt;		/* the # of cached nat entries */
 	unsigned int dirty_nat_cnt;	/* total num of nat entries in set */
 	unsigned int nat_blocks;	/* # of nat blocks */

2.18.0

From: Chao Yu <[email protected]>

generic/260 reported below error:

[+] Default length with start set (should succeed)
[+] Length beyond the end of fs (should succeed)
[+] Length beyond the end of fs with start set (should succeed)
+./tests/generic/260: line 94: [: 18446744073709551615: integer expression expected +./tests/generic/260: line 104: [: 18446744073709551615: integer expression expected
Test done
...

In f2fs_trim_fs(), if there is no discard being trimmed, we need to correct range->len before return.

---
 fs/f2fs/segment.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

index 24b7147456e9..7b470a1fe92b 100644
@@ -2626,8 +2626,9 @@ int f2fs_trim_fs(struct f2fs_sb_info *sbi, struct fstrim_range *range)
 
 	trimmed += __wait_discard_cmd_range(sbi, &dpolicy,
 					start_block, end_block);
-	range->len = F2FS_BLK_TO_BYTES(trimmed);
 out:
+	if (!err)
+		range->len = F2FS_BLK_TO_BYTES(trimmed);
 	return err;
 }
 

2.18.0