f2fs: don't need inode lock for system hidden quota

Let's avoid false-alarmed lockdep warning.

[   58.914674] [T1501146] -> #2 (&sb->s_type->i_mutex_key#20){+.+.}-{3:3}:
[   58.915975] [T1501146] system_server:        down_write+0x7c/0xe0
[   58.916738] [T1501146] system_server:        f2fs_quota_sync+0x60/0x1a8
[   58.917563] [T1501146] system_server:        block_operations+0x16c/0x43c
[   58.918410] [T1501146] system_server:        f2fs_write_checkpoint+0x114/0x318
[   58.919312] [T1501146] system_server:        f2fs_issue_checkpoint+0x178/0x21c
[   58.920214] [T1501146] system_server:        f2fs_sync_fs+0x48/0x6c
[   58.920999] [T1501146] system_server:        f2fs_do_sync_file+0x334/0x738
[   58.921862] [T1501146] system_server:        f2fs_sync_file+0x30/0x48
[   58.922667] [T1501146] system_server:        __arm64_sys_fsync+0x84/0xf8
[   58.923506] [T1501146] system_server:        el0_svc_common.llvm.12821150825140585682+0xd8/0x20c
[   58.924604] [T1501146] system_server:        do_el0_svc+0x28/0xa0
[   58.925366] [T1501146] system_server:        el0_svc+0x24/0x38
[   58.926094] [T1501146] system_server:        el0_sync_handler+0x88/0xec
[   58.926920] [T1501146] system_server:        el0_sync+0x1b4/0x1c0

[   58.927681] [T1501146] -> #1 (&sbi->cp_global_sem){+.+.}-{3:3}:
[   58.928889] [T1501146] system_server:        down_write+0x7c/0xe0
[   58.929650] [T1501146] system_server:        f2fs_write_checkpoint+0xbc/0x318
[   58.930541] [T1501146] system_server:        f2fs_issue_checkpoint+0x178/0x21c
[   58.931443] [T1501146] system_server:        f2fs_sync_fs+0x48/0x6c
[   58.932226] [T1501146] system_server:        sync_filesystem+0xac/0x130
[   58.933053] [T1501146] system_server:        generic_shutdown_super+0x38/0x150
[   58.933958] [T1501146] system_server:        kill_block_super+0x24/0x58
[   58.934791] [T1501146] system_server:        kill_f2fs_super+0xcc/0x124
[   58.935618] [T1501146] system_server:        deactivate_locked_super+0x90/0x120
[   58.936529] [T1501146] system_server:        deactivate_super+0x74/0xac
[   58.937356] [T1501146] system_server:        cleanup_mnt+0x128/0x168
[   58.938150] [T1501146] system_server:        __cleanup_mnt+0x18/0x28
[   58.938944] [T1501146] system_server:        task_work_run+0xb8/0x14c
[   58.939749] [T1501146] system_server:        do_notify_resume+0x114/0x1e8
[   58.940595] [T1501146] system_server:        work_pending+0xc/0x5f0

[   58.941375] [T1501146] -> #0 (&sbi->gc_lock){+.+.}-{3:3}:
[   58.942519] [T1501146] system_server:        __lock_acquire+0x1270/0x2868
[   58.943366] [T1501146] system_server:        lock_acquire+0x114/0x294
[   58.944169] [T1501146] system_server:        down_write+0x7c/0xe0
[   58.944930] [T1501146] system_server:        f2fs_issue_checkpoint+0x13c/0x21c
[   58.945831] [T1501146] system_server:        f2fs_sync_fs+0x48/0x6c
[   58.946614] [T1501146] system_server:        f2fs_do_sync_file+0x334/0x738
[   58.947472] [T1501146] system_server:        f2fs_ioc_commit_atomic_write+0xc8/0x14c
[   58.948439] [T1501146] system_server:        __f2fs_ioctl+0x674/0x154c
[   58.949253] [T1501146] system_server:        f2fs_ioctl+0x54/0x88
[   58.950018] [T1501146] system_server:        __arm64_sys_ioctl+0xa8/0x110
[   58.950865] [T1501146] system_server:        el0_svc_common.llvm.12821150825140585682+0xd8/0x20c
[   58.951965] [T1501146] system_server:        do_el0_svc+0x28/0xa0
[   58.952727] [T1501146] system_server:        el0_svc+0x24/0x38
[   58.953454] [T1501146] system_server:        el0_sync_handler+0x88/0xec
[   58.954279] [T1501146] system_server:        el0_sync+0x1b4/0x1c0

Cc: [email protected]
Signed-off-by: Jaegeuk Kim <[email protected]>

fs/f2fs/super.c

@@ -2684,7 +2684,8 @@ int f2fs_quota_sync(struct super_block *sb, int type)
 		if (!sb_has_quota_active(sb, cnt))
 			continue;
 
-		inode_lock(dqopt->files[cnt]);
+		if (!f2fs_sb_has_quota_ino(sbi))
+			inode_lock(dqopt->files[cnt]);
 
 		/*
 		 * do_quotactl
@@ -2703,7 +2704,8 @@ int f2fs_quota_sync(struct super_block *sb, int type)
 		f2fs_up_read(&sbi->quota_sem);
 		f2fs_unlock_op(sbi);
 
-		inode_unlock(dqopt->files[cnt]);
+		if (!f2fs_sb_has_quota_ino(sbi))
+			inode_unlock(dqopt->files[cnt]);
 
 		if (ret)
 			break;