quota: provide interface for readding allocated space into reserved space

ext4 needs to convert allocated (metadata) blocks back into blocks
reserved for delayed allocation. Add functions into quota code for
supporting such operation.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/include/linux/quotaops.h b/include/linux/quotaops.h
index 1c50093..6965fe3 100644
--- a/include/linux/quotaops.h
+++ b/include/linux/quotaops.h
@@ -41,6 +41,7 @@
 void inode_add_rsv_space(struct inode *inode, qsize_t number);
 void inode_claim_rsv_space(struct inode *inode, qsize_t number);
 void inode_sub_rsv_space(struct inode *inode, qsize_t number);
+void inode_reclaim_rsv_space(struct inode *inode, qsize_t number);
 
 void dquot_initialize(struct inode *inode);
 void dquot_drop(struct inode *inode);
@@ -59,6 +60,7 @@
 
 int dquot_claim_space_nodirty(struct inode *inode, qsize_t number);
 void dquot_free_inode(const struct inode *inode);
+void dquot_reclaim_space_nodirty(struct inode *inode, qsize_t number);
 
 int dquot_disable(struct super_block *sb, int type, unsigned int flags);
 /* Suspend quotas on remount RO */
@@ -238,6 +240,13 @@
 	return 0;
 }
 
+static inline int dquot_reclaim_space_nodirty(struct inode *inode,
+					      qsize_t number)
+{
+	inode_sub_bytes(inode, number);
+	return 0;
+}
+
 static inline int dquot_disable(struct super_block *sb, int type,
 		unsigned int flags)
 {
@@ -336,6 +345,12 @@
 	return ret;
 }
 
+static inline void dquot_reclaim_block(struct inode *inode, qsize_t nr)
+{
+	dquot_reclaim_space_nodirty(inode, nr << inode->i_blkbits);
+	mark_inode_dirty_sync(inode);
+}
+
 static inline void dquot_free_space_nodirty(struct inode *inode, qsize_t nr)
 {
 	__dquot_free_space(inode, nr, 0);