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/*
* QNX4 file system, Linux implementation.
*
* Version : 0.1
*
* Using parts of the xiafs filesystem.
*
* History :
*
* 24-03-1998 by Richard Frowijn : first release.
*/
#include <linux/config.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
#include <linux/locks.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
#include <linux/qnx4_fs.h>
#include <asm/segment.h>
#include <asm/system.h>
#define blocksize QNX4_BLOCK_SIZE
/*
* The functions for qnx4 fs file synchronization.
*/
#ifdef CONFIG_QNX4FS_RW
static int sync_block(struct inode *inode, unsigned short *block, int wait)
{
struct buffer_head *bh;
unsigned short tmp;
if (!*block)
return 0;
tmp = *block;
bh = get_hash_table(inode->i_dev, *block, blocksize);
if (!bh)
return 0;
if (*block != tmp) {
brelse(bh);
return 1;
}
if (wait && buffer_req(bh) && !buffer_uptodate(bh)) {
brelse(bh);
return -1;
}
if (wait || !buffer_uptodate(bh) || !buffer_dirty(bh)) {
brelse(bh);
return 0;
}
ll_rw_block(WRITE, 1, &bh);
atomic_dec(&bh->b_count);
return 0;
}
static int sync_iblock(struct inode *inode, unsigned short *iblock,
struct buffer_head **bh, int wait)
{
int rc;
unsigned short tmp;
*bh = NULL;
tmp = *iblock;
if (!tmp)
return 0;
rc = sync_block(inode, iblock, wait);
if (rc)
return rc;
*bh = bread(inode->i_dev, tmp, blocksize);
if (tmp != *iblock) {
brelse(*bh);
*bh = NULL;
return 1;
}
if (!*bh)
return -1;
return 0;
}
static int sync_direct(struct inode *inode, int wait)
{
int i;
int rc, err = 0;
for (i = 0; i < 7; i++) {
rc = sync_block(inode,
(unsigned short *) inode->u.qnx4_i.i_first_xtnt.xtnt_blk + i, wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
return err;
}
static int sync_indirect(struct inode *inode, unsigned short *iblock, int wait)
{
int i;
struct buffer_head *ind_bh;
int rc, err = 0;
rc = sync_iblock(inode, iblock, &ind_bh, wait);
if (rc || !ind_bh)
return rc;
for (i = 0; i < 512; i++) {
rc = sync_block(inode,
((unsigned short *) ind_bh->b_data) + i,
wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
brelse(ind_bh);
return err;
}
static int sync_dindirect(struct inode *inode, unsigned short *diblock,
int wait)
{
int i;
struct buffer_head *dind_bh;
int rc, err = 0;
rc = sync_iblock(inode, diblock, &dind_bh, wait);
if (rc || !dind_bh)
return rc;
for (i = 0; i < 512; i++) {
rc = sync_indirect(inode,
((unsigned short *) dind_bh->b_data) + i,
wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
brelse(dind_bh);
return err;
}
int qnx4_sync_file(struct file *file, struct dentry *dentry, int datasync)
{
struct inode *inode = dentry->d_inode;
int wait, err = 0;
(void) file;
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
S_ISLNK(inode->i_mode)))
return -EINVAL;
lock_kernel();
for (wait = 0; wait <= 1; wait++) {
err |= sync_direct(inode, wait);
}
err |= qnx4_sync_inode(inode);
unlock_kernel();
return (err < 0) ? -EIO : 0;
}
#endif
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