f2fs: fix to keep project quota consistent

This patch does below changes to keep consistence of project quota data
in sudden power-cut case:
- update inode.i_projid and project quota atomically under lock_op() in
f2fs_ioc_setproject()
- recover inode.i_projid and project quota in recover_inode()
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/f2fs.h

@@ -2811,6 +2811,7 @@ void f2fs_truncate_data_blocks_range(struct dnode_of_data *dn, int count);
 int f2fs_precache_extents(struct inode *inode);
 long f2fs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg);
 long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
+int f2fs_transfer_project_quota(struct inode *inode, kprojid_t kprojid);
 int f2fs_pin_file_control(struct inode *inode, bool inc);
 
 /*

fs/f2fs/file.c

@@ -2613,13 +2613,29 @@ static int f2fs_ioc_get_features(struct file *filp, unsigned long arg)
 }
 
 #ifdef CONFIG_QUOTA
+int f2fs_transfer_project_quota(struct inode *inode, kprojid_t kprojid)
+{
+	struct dquot *transfer_to[MAXQUOTAS] = {};
+	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
+	struct super_block *sb = sbi->sb;
+	int err = 0;
+
+	transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
+	if (!IS_ERR(transfer_to[PRJQUOTA])) {
+		err = __dquot_transfer(inode, transfer_to);
+		if (err)
+			set_sbi_flag(sbi, SBI_QUOTA_NEED_REPAIR);
+		dqput(transfer_to[PRJQUOTA]);
+	}
+	return err;
+}
+
 static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
 {
 	struct inode *inode = file_inode(filp);
 	struct f2fs_inode_info *fi = F2FS_I(inode);
 	struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
 	struct super_block *sb = sbi->sb;
-	struct dquot *transfer_to[MAXQUOTAS] = {};
 	struct page *ipage;
 	kprojid_t kprojid;
 	int err;
@@ -2660,21 +2676,24 @@ static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
 	if (err)
 		return err;
 
-	transfer_to[PRJQUOTA] = dqget(sb, make_kqid_projid(kprojid));
-	if (!IS_ERR(transfer_to[PRJQUOTA])) {
-		err = __dquot_transfer(inode, transfer_to);
-		dqput(transfer_to[PRJQUOTA]);
-		if (err)
-			goto out_dirty;
-	}
+	f2fs_lock_op(sbi);
+	err = f2fs_transfer_project_quota(inode, kprojid);
+	if (err)
+		goto out_unlock;
 
 	F2FS_I(inode)->i_projid = kprojid;
 	inode->i_ctime = current_time(inode);
-out_dirty:
 	f2fs_mark_inode_dirty_sync(inode, true);
+out_unlock:
+	f2fs_unlock_op(sbi);
 	return err;
 }
 #else
+int f2fs_transfer_project_quota(struct inode *inode, kprojid_t kprojid)
+{
+	return 0;
+}
+
 static int f2fs_ioc_setproject(struct file *filp, __u32 projid)
 {
 	if (projid != F2FS_DEF_PROJID)

fs/f2fs/recovery.c

@@ -254,10 +254,18 @@ static int recover_inode(struct inode *inode, struct page *page)
 			F2FS_FITS_IN_INODE(raw, le16_to_cpu(raw->i_extra_isize),
 								i_projid)) {
 			projid_t i_projid;
+			kprojid_t kprojid;
 
 			i_projid = (projid_t)le32_to_cpu(raw->i_projid);
-			F2FS_I(inode)->i_projid =
-				make_kprojid(&init_user_ns, i_projid);
+			kprojid = make_kprojid(&init_user_ns, i_projid);
+
+			if (!projid_eq(kprojid, F2FS_I(inode)->i_projid)) {
+				err = f2fs_transfer_project_quota(inode,
+								kprojid);
+				if (err)
+					return err;
+				F2FS_I(inode)->i_projid = kprojid;
+			}
 		}
 	}