f2fs: avoid sleeping under spin_lock

In the call trace below, we might sleep in function dput().

So in order to avoid sleeping under spin_lock, we remove f2fs_mark_inode_dirty_sync
from __try_update_largest_extent && __drop_largest_extent.

BUG: sleeping function called from invalid context at fs/dcache.c:796
Call trace:
	dump_backtrace+0x0/0x3f4
	show_stack+0x24/0x30
	dump_stack+0xe0/0x138
	___might_sleep+0x2a8/0x2c8
	__might_sleep+0x78/0x10c
	dput+0x7c/0x750
	block_dump___mark_inode_dirty+0x120/0x17c
	__mark_inode_dirty+0x344/0x11f0
	f2fs_mark_inode_dirty_sync+0x40/0x50
	__insert_extent_tree+0x2e0/0x2f4
	f2fs_update_extent_tree_range+0xcf4/0xde8
	f2fs_update_extent_cache+0x114/0x12c
	f2fs_update_data_blkaddr+0x40/0x50
	write_data_page+0x150/0x314
	do_write_data_page+0x648/0x2318
	__write_data_page+0xdb4/0x1640
	f2fs_write_cache_pages+0x768/0xafc
	__f2fs_write_data_pages+0x590/0x1218
	f2fs_write_data_pages+0x64/0x74
	do_writepages+0x74/0xe4
	__writeback_single_inode+0xdc/0x15f0
	writeback_sb_inodes+0x574/0xc98
	__writeback_inodes_wb+0x190/0x204
	wb_writeback+0x730/0xf14
	wb_check_old_data_flush+0x1bc/0x1c8
	wb_workfn+0x554/0xf74
	process_one_work+0x440/0x118c
	worker_thread+0xac/0x974
	kthread+0x1a0/0x1c8
	ret_from_fork+0x10/0x1c

Signed-off-by: Zhikang Zhang <zhangzhikang1@huawei.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 85949c2..faff5cc 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -571,6 +571,7 @@
 	struct list_head list;		/* to be used by sbi->zombie_list */
 	rwlock_t lock;			/* protect extent info rb-tree */
 	atomic_t node_cnt;		/* # of extent node in rb-tree*/
+	bool largest_updated;		/* largest extent updated */
 };
 
 /*
@@ -753,12 +754,12 @@
 }
 
 extern void f2fs_mark_inode_dirty_sync(struct inode *inode, bool sync);
-static inline void __try_update_largest_extent(struct inode *inode,
-			struct extent_tree *et, struct extent_node *en)
+static inline void __try_update_largest_extent(struct extent_tree *et,
+						struct extent_node *en)
 {
 	if (en->ei.len > et->largest.len) {
 		et->largest = en->ei;
-		f2fs_mark_inode_dirty_sync(inode, true);
+		et->largest_updated = true;
 	}
 }