historical/gems-kernel.git/source/THIRDPARTY/linux-old/fs/sysv/fsync.c

200 lines
4.3 KiB
C

/*
* linux/fs/sysv/fsync.c
*
* minix/fsync.c
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 1993 Stephen Tweedie (sct@dcs.ed.ac.uk)
*
* coh/fsync.c
* Copyright (C) 1993 Pascal Haible, Bruno Haible
*
* sysv/fsync.c
* Copyright (C) 1993 Bruno Haible
*
* SystemV/Coherent fsync primitive
*/
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/fs.h>
#include <linux/sysv_fs.h>
/* return values: 0 means OK/done, 1 means redo, -1 means I/O error. */
/* Sync one block. The block number is
* from_coh_ulong(*blockp) if convert=1, *blockp if convert=0.
*/
static int sync_block (struct inode * inode, unsigned long * blockp, int convert, int wait)
{
struct buffer_head * bh;
unsigned long tmp, block;
struct super_block * sb;
block = tmp = *blockp;
if (convert)
block = from_coh_ulong(block);
if (!block)
return 0;
sb = inode->i_sb;
bh = get_hash_table(inode->i_dev, (block >> sb->sv_block_size_ratio_bits) + sb->sv_block_base, BLOCK_SIZE);
if (!bh)
return 0;
if (*blockp != tmp) {
brelse (bh);
return 1;
}
if (wait && bh->b_req && !bh->b_uptodate) {
brelse(bh);
return -1;
}
if (wait || !bh->b_uptodate || !bh->b_dirt) {
brelse(bh);
return 0;
}
ll_rw_block(WRITE, 1, &bh);
bh->b_count--;
return 0;
}
/* Sync one block full of indirect pointers and read it because we'll need it. */
static int sync_iblock (struct inode * inode, unsigned long * iblockp, int convert,
struct buffer_head * *bh, char * *bh_data, int wait)
{
int rc;
unsigned long tmp, block;
*bh = NULL;
block = tmp = *iblockp;
if (convert)
block = from_coh_ulong(block);
if (!block)
return 0;
rc = sync_block (inode, iblockp, convert, wait);
if (rc)
return rc;
*bh = sysv_bread(inode->i_sb, inode->i_dev, block, bh_data);
if (tmp != *iblockp) {
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 < 10; i++) {
rc = sync_block (inode, inode->u.sysv_i.i_data + i, 0, wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
return err;
}
static int sync_indirect(struct inode *inode, unsigned long *iblockp, int convert, int wait)
{
int i;
struct buffer_head * ind_bh;
char * ind_bh_data;
int rc, err = 0;
struct super_block * sb;
rc = sync_iblock (inode, iblockp, convert, &ind_bh, &ind_bh_data, wait);
if (rc || !ind_bh)
return rc;
sb = inode->i_sb;
for (i = 0; i < sb->sv_ind_per_block; i++) {
rc = sync_block (inode,
((unsigned long *) ind_bh_data) + i, sb->sv_convert,
wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
brelse(ind_bh);
return err;
}
static int sync_dindirect(struct inode *inode, unsigned long *diblockp, int convert,
int wait)
{
int i;
struct buffer_head * dind_bh;
char * dind_bh_data;
int rc, err = 0;
struct super_block * sb;
rc = sync_iblock (inode, diblockp, convert, &dind_bh, &dind_bh_data, wait);
if (rc || !dind_bh)
return rc;
sb = inode->i_sb;
for (i = 0; i < sb->sv_ind_per_block; i++) {
rc = sync_indirect (inode,
((unsigned long *) dind_bh_data) + i, sb->sv_convert,
wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
brelse(dind_bh);
return err;
}
static int sync_tindirect(struct inode *inode, unsigned long *tiblockp, int convert,
int wait)
{
int i;
struct buffer_head * tind_bh;
char * tind_bh_data;
int rc, err = 0;
struct super_block * sb;
rc = sync_iblock (inode, tiblockp, convert, &tind_bh, &tind_bh_data, wait);
if (rc || !tind_bh)
return rc;
sb = inode->i_sb;
for (i = 0; i < sb->sv_ind_per_block; i++) {
rc = sync_dindirect (inode,
((unsigned long *) tind_bh_data) + i, sb->sv_convert,
wait);
if (rc > 0)
break;
if (rc)
err = rc;
}
brelse(tind_bh);
return err;
}
int sysv_sync_file(struct inode * inode, struct file * file)
{
int wait, err = 0;
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
S_ISLNK(inode->i_mode)))
return -EINVAL;
for (wait=0; wait<=1; wait++) {
err |= sync_direct(inode, wait);
err |= sync_indirect(inode, inode->u.sysv_i.i_data+10, 0, wait);
err |= sync_dindirect(inode, inode->u.sysv_i.i_data+11, 0, wait);
err |= sync_tindirect(inode, inode->u.sysv_i.i_data+12, 0, wait);
}
err |= sysv_sync_inode (inode);
return (err < 0) ? -EIO : 0;
}