/* *  linux/fs/truncate.c * *  (C) 1991  Linus Torvalds */#include <linux/sched.h>#include <sys/stat.h>static void free_ind(int dev,int block){	struct buffer_head * bh;	unsigned short * p;	int i;	if (!block)		return;	if (bh=bread(dev,block)) {		p = (unsigned short *) bh->b_data;		for (i=0;i<512;i++,p++)			if (*p)				free_block(dev,*p);		brelse(bh);	}	free_block(dev,block);}static void free_dind(int dev,int block){	struct buffer_head * bh;	unsigned short * p;	int i;	if (!block)		return;	if (bh=bread(dev,block)) {		p = (unsigned short *) bh->b_data;		for (i=0;i<512;i++,p++)			if (*p)				free_ind(dev,*p);		brelse(bh);	}	free_block(dev,block);}void truncate(struct m_inode * inode){	int i;	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))		return;	for (i=0;i<7;i++)		if (inode->i_zone[i]) {			free_block(inode->i_dev,inode->i_zone[i]);			inode->i_zone[i]=0;		}	free_ind(inode->i_dev,inode->i_zone[7]);	free_dind(inode->i_dev,inode->i_zone[8]);	inode->i_zone[7] = inode->i_zone[8] = 0;	inode->i_size = 0;	inode->i_dirt = 1;	inode->i_mtime = inode->i_ctime = CURRENT_TIME;}