quota: unify ->get_dqblk

Pass the larger struct fs_disk_quota to the ->get_dqblk operation so
that the Q_GETQUOTA and Q_XGETQUOTA operations can be implemented
with a single filesystem operation and we can retire the ->get_xquota
operation.  The additional information (RT-subvolume accounting and
warn counts) are left zero for the VFS quota implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index e6fa7ac..d32a486 100644
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -63,7 +63,8 @@
 int vfs_quota_sync(struct super_block *sb, int type, int wait);
 int vfs_get_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
 int vfs_set_dqinfo(struct super_block *sb, int type, struct if_dqinfo *ii);
-int vfs_get_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);
+int vfs_get_dqblk(struct super_block *sb, int type, qid_t id,
+		struct fs_disk_quota *di);
 int vfs_set_dqblk(struct super_block *sb, int type, qid_t id, struct if_dqblk *di);
 
 int dquot_transfer(struct inode *inode, struct iattr *iattr);