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/*
* 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;
}
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