quota: unify quota init condition in setattr

Quota must being initialized if size or uid/git changes requested.
But initialization performed in two different places:
in case of i_size file system is responsible for dquot init
, but in case of uid/gid init will be called internally in
dquot_transfer().
This ambiguity makes code harder to understand.
Let's move this logic to one common helper function.
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/ext2/inode.c

@@ -1466,7 +1466,7 @@ int ext2_setattr(struct dentry *dentry, struct iattr *iattr)
 	if (error)
 		return error;
 
-	if (iattr->ia_valid & ATTR_SIZE)
+	if (is_quota_modification(inode, iattr))
 		dquot_initialize(inode);
 	if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
 	    (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {

fs/ext3/inode.c

@@ -3151,7 +3151,7 @@ int ext3_setattr(struct dentry *dentry, struct iattr *attr)
 	if (error)
 		return error;
 
-	if (ia_valid & ATTR_SIZE)
+	if (is_quota_modification(inode, attr))
 		dquot_initialize(inode);
 	if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
 		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {

fs/ext4/inode.c

@@ -5425,7 +5425,7 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr)
 	if (error)
 		return error;
 
-	if (ia_valid & ATTR_SIZE)
+	if (is_quota_modification(inode, attr))
 		dquot_initialize(inode);
 	if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
 		(ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {

fs/jfs/file.c

@@ -98,7 +98,7 @@ int jfs_setattr(struct dentry *dentry, struct iattr *iattr)
 	if (rc)
 		return rc;
 
-	if (iattr->ia_valid & ATTR_SIZE)
+	if (is_quota_modification(inode, iattr))
 		dquot_initialize(inode);
 	if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||
 	    (iattr->ia_valid & ATTR_GID && iattr->ia_gid != inode->i_gid)) {

fs/ocfs2/file.c

@@ -966,10 +966,10 @@ int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
 	if (status)
 		return status;
 
+	if (is_quota_modification(inode, attr))
+		dquot_initialize(inode);
 	size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
 	if (size_change) {
-		dquot_initialize(inode);
-
 		status = ocfs2_rw_lock(inode, 1);
 		if (status < 0) {
 			mlog_errno(status);

fs/quota/dquot.c

@@ -1822,10 +1822,9 @@ int dquot_transfer(struct inode *inode, struct iattr *iattr)
 		mask |= 1 << GRPQUOTA;
 		chid[GRPQUOTA] = iattr->ia_gid;
 	}
-	if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode)) {
-		dquot_initialize(inode);
+	if (sb_any_quota_active(inode->i_sb) && !IS_NOQUOTA(inode))
 		return __dquot_transfer(inode, chid, mask);
-	}
+
 	return 0;
 }
 EXPORT_SYMBOL(dquot_transfer);

fs/reiserfs/inode.c

@@ -3076,9 +3076,10 @@ int reiserfs_setattr(struct dentry *dentry, struct iattr *attr)
 	ia_valid = attr->ia_valid &= ~(ATTR_KILL_SUID|ATTR_KILL_SGID);
 
 	depth = reiserfs_write_lock_once(inode->i_sb);
-	if (attr->ia_valid & ATTR_SIZE) {
+	if (is_quota_modification(inode, attr))
 		dquot_initialize(inode);
 
+	if (attr->ia_valid & ATTR_SIZE) {
 		/* version 2 items will be caught by the s_maxbytes check
 		 ** done for us in vmtruncate
 		 */

fs/udf/file.c

@@ -227,7 +227,7 @@ int udf_setattr(struct dentry *dentry, struct iattr *iattr)
 	if (error)
 		return error;
 
-	if (iattr->ia_valid & ATTR_SIZE)
+	if (is_quota_modification(inode, iattr))
 		dquot_initialize(inode);
 
 	if ((iattr->ia_valid & ATTR_UID && iattr->ia_uid != inode->i_uid) ||

fs/ufs/truncate.c

@@ -518,18 +518,18 @@ int ufs_setattr(struct dentry *dentry, struct iattr *attr)
 	if (error)
 		return error;
 
+	if (is_quota_modification(inode, attr))
+		dquot_initialize(inode);
+
 	if ((ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
 	    (ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
 		error = dquot_transfer(inode, attr);
 		if (error)
 			return error;
 	}
-	if (ia_valid & ATTR_SIZE &&
-	    attr->ia_size != i_size_read(inode)) {
+	if (ia_valid & ATTR_SIZE && attr->ia_size != inode->i_size) {
 		loff_t old_i_size = inode->i_size;
 
-		dquot_initialize(inode);
-
 		error = vmtruncate(inode, attr->ia_size);
 		if (error)
 			return error;

include/linux/quotaops.h

@@ -14,6 +14,14 @@ static inline struct quota_info *sb_dqopt(struct super_block *sb)
 	return &sb->s_dquot;
 }
 
+/* i_mutex must being held */
+static inline bool is_quota_modification(struct inode *inode, struct iattr *ia)
+{
+	return (ia->ia_valid & ATTR_SIZE && ia->ia_size != inode->i_size) ||
+		(ia->ia_valid & ATTR_UID && ia->ia_uid != inode->i_uid) ||
+		(ia->ia_valid & ATTR_GID && ia->ia_gid != inode->i_gid);
+}
+
 #if defined(CONFIG_QUOTA)
 
 /*