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/*
* linux/fs/sysv/inode.c
*
* minix/inode.c
* Copyright (C) 1991, 1992 Linus Torvalds
*
* xenix/inode.c
* Copyright (C) 1992 Doug Evans
*
* coh/inode.c
* Copyright (C) 1993 Pascal Haible, Bruno Haible
*
* sysv/inode.c
* Copyright (C) 1993 Paul B. Monday
*
* sysv/inode.c
* Copyright (C) 1993 Bruno Haible
* Copyright (C) 1997, 1998 Krzysztof G. Baranowski
*
* This file contains code for allocating/freeing inodes and for read/writing
* the superblock.
*/
#include <linux/fs.h>
#include <linux/sysv_fs.h>
#include <linux/locks.h>
#include <linux/smp_lock.h>
#include <linux/highuid.h>
#include <asm/byteorder.h>
/* This is only called on sync() and umount(), when s_dirt=1. */
static void sysv_write_super(struct super_block *sb)
{
if (!(sb->s_flags & MS_RDONLY)) {
/* If we are going to write out the super block,
then attach current time stamp.
But if the filesystem was marked clean, keep it clean. */
unsigned long time = CURRENT_TIME;
unsigned long old_time = fs32_to_cpu(sb, *sb->sv_sb_time);
if (sb->sv_type == FSTYPE_SYSV4)
if (*sb->sv_sb_state == cpu_to_fs32(sb, 0x7c269d38 - old_time))
*sb->sv_sb_state = cpu_to_fs32(sb, 0x7c269d38 - time);
*sb->sv_sb_time = cpu_to_fs32(sb, time);
mark_buffer_dirty(sb->sv_bh2);
}
sb->s_dirt = 0;
}
static void sysv_put_super(struct super_block *sb)
{
if (!(sb->s_flags & MS_RDONLY)) {
/* XXX ext2 also updates the state here */
mark_buffer_dirty(sb->sv_bh1);
if (sb->sv_bh1 != sb->sv_bh2)
mark_buffer_dirty(sb->sv_bh2);
}
brelse(sb->sv_bh1);
if (sb->sv_bh1 != sb->sv_bh2)
brelse(sb->sv_bh2);
}
static int sysv_statfs(struct super_block *sb, struct statfs *buf)
{
buf->f_type = sb->s_magic;
buf->f_bsize = sb->s_blocksize;
buf->f_blocks = sb->sv_ndatazones;
buf->f_bavail = buf->f_bfree = sysv_count_free_blocks(sb);
buf->f_files = sb->sv_ninodes;
buf->f_ffree = sysv_count_free_inodes(sb);
buf->f_namelen = SYSV_NAMELEN;
return 0;
}
/*
* NXI <-> N0XI for PDP, XIN <-> XIN0 for le32, NIX <-> 0NIX for be32
*/
static inline void read3byte(struct super_block *sb,
unsigned char * from, unsigned char * to)
{
if (sb->sv_bytesex == BYTESEX_PDP) {
to[0] = from[0];
to[1] = 0;
to[2] = from[1];
to[3] = from[2];
} else if (sb->sv_bytesex == BYTESEX_LE) {
to[0] = from[0];
to[1] = from[1];
to[2] = from[2];
to[3] = 0;
} else {
to[0] = 0;
to[1] = from[0];
to[2] = from[1];
to[3] = from[2];
}
}
static inline void write3byte(struct super_block *sb,
unsigned char * from, unsigned char * to)
{
if (sb->sv_bytesex == BYTESEX_PDP) {
to[0] = from[0];
to[1] = from[2];
to[2] = from[3];
} else if (sb->sv_bytesex == BYTESEX_LE) {
to[0] = from[0];
to[1] = from[1];
to[2] = from[2];
} else {
to[0] = from[1];
to[1] = from[2];
to[2] = from[3];
}
}
static struct inode_operations sysv_symlink_inode_operations = {
readlink: page_readlink,
follow_link: page_follow_link,
};
void sysv_set_inode(struct inode *inode, dev_t rdev)
{
if (S_ISREG(inode->i_mode)) {
inode->i_op = &sysv_file_inode_operations;
inode->i_fop = &sysv_file_operations;
inode->i_mapping->a_ops = &sysv_aops;
} else if (S_ISDIR(inode->i_mode)) {
inode->i_op = &sysv_dir_inode_operations;
inode->i_fop = &sysv_dir_operations;
inode->i_mapping->a_ops = &sysv_aops;
} else if (S_ISLNK(inode->i_mode)) {
if (inode->i_blocks) {
inode->i_op = &sysv_symlink_inode_operations;
inode->i_mapping->a_ops = &sysv_aops;
} else
inode->i_op = &sysv_fast_symlink_inode_operations;
} else
init_special_inode(inode, inode->i_mode, rdev);
}
static void sysv_read_inode(struct inode *inode)
{
struct super_block * sb = inode->i_sb;
struct buffer_head * bh;
struct sysv_inode * raw_inode;
unsigned int block, ino;
dev_t rdev = 0;
ino = inode->i_ino;
if (!ino || ino > sb->sv_ninodes) {
printk("Bad inode number on dev %s"
": %d is out of range\n",
kdevname(inode->i_dev), ino);
goto bad_inode;
}
raw_inode = sysv_raw_inode(sb, ino, &bh);
if (!raw_inode) {
printk("Major problem: unable to read inode from dev %s\n",
bdevname(inode->i_dev));
goto bad_inode;
}
/* SystemV FS: kludge permissions if ino==SYSV_ROOT_INO ?? */
inode->i_mode = fs16_to_cpu(sb, raw_inode->i_mode);
inode->i_uid = (uid_t)fs16_to_cpu(sb, raw_inode->i_uid);
inode->i_gid = (gid_t)fs16_to_cpu(sb, raw_inode->i_gid);
inode->i_nlink = fs16_to_cpu(sb, raw_inode->i_nlink);
inode->i_size = fs32_to_cpu(sb, raw_inode->i_size);
inode->i_atime = fs32_to_cpu(sb, raw_inode->i_atime);
inode->i_mtime = fs32_to_cpu(sb, raw_inode->i_mtime);
inode->i_ctime = fs32_to_cpu(sb, raw_inode->i_ctime);
inode->i_blocks = inode->i_blksize = 0;
for (block = 0; block < 10+1+1+1; block++)
read3byte(sb, &raw_inode->i_a.i_addb[3*block],
(unsigned char*)&inode->u.sysv_i.i_data[block]);
brelse(bh);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
rdev = (u16)fs32_to_cpu(sb, inode->u.sysv_i.i_data[0]);
inode->u.sysv_i.i_dir_start_lookup = 0;
sysv_set_inode(inode, rdev);
return;
bad_inode:
make_bad_inode(inode);
return;
}
static struct buffer_head * sysv_update_inode(struct inode * inode)
{
struct super_block * sb = inode->i_sb;
struct buffer_head * bh;
struct sysv_inode * raw_inode;
unsigned int ino, block;
ino = inode->i_ino;
if (!ino || ino > sb->sv_ninodes) {
printk("Bad inode number on dev %s: %d is out of range\n",
bdevname(inode->i_dev), ino);
return 0;
}
raw_inode = sysv_raw_inode(sb, ino, &bh);
if (!raw_inode) {
printk("unable to read i-node block\n");
return 0;
}
raw_inode->i_mode = cpu_to_fs16(sb, inode->i_mode);
raw_inode->i_uid = cpu_to_fs16(sb, fs_high2lowuid(inode->i_uid));
raw_inode->i_gid = cpu_to_fs16(sb, fs_high2lowgid(inode->i_gid));
raw_inode->i_nlink = cpu_to_fs16(sb, inode->i_nlink);
raw_inode->i_size = cpu_to_fs32(sb, inode->i_size);
raw_inode->i_atime = cpu_to_fs32(sb, inode->i_atime);
raw_inode->i_mtime = cpu_to_fs32(sb, inode->i_mtime);
raw_inode->i_ctime = cpu_to_fs32(sb, inode->i_ctime);
if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode))
inode->u.sysv_i.i_data[0] =
cpu_to_fs32(sb, kdev_t_to_nr(inode->i_rdev));
for (block = 0; block < 10+1+1+1; block++)
write3byte(sb, (unsigned char*)&inode->u.sysv_i.i_data[block],
&raw_inode->i_a.i_addb[3*block]);
mark_buffer_dirty(bh);
return bh;
}
void sysv_write_inode(struct inode * inode, int wait)
{
struct buffer_head *bh;
lock_kernel();
bh = sysv_update_inode(inode);
brelse(bh);
unlock_kernel();
}
int sysv_sync_inode(struct inode * inode)
{
int err = 0;
struct buffer_head *bh;
bh = sysv_update_inode(inode);
if (bh && buffer_dirty(bh)) {
ll_rw_block(WRITE, 1, &bh);
wait_on_buffer(bh);
if (buffer_req(bh) && !buffer_uptodate(bh)) {
printk ("IO error syncing sysv inode [%s:%08lx]\n",
bdevname(inode->i_dev), inode->i_ino);
err = -1;
}
}
else if (!bh)
err = -1;
brelse (bh);
return err;
}
static void sysv_delete_inode(struct inode *inode)
{
lock_kernel();
inode->i_size = 0;
sysv_truncate(inode);
sysv_free_inode(inode);
unlock_kernel();
}
struct super_operations sysv_sops = {
read_inode: sysv_read_inode,
write_inode: sysv_write_inode,
delete_inode: sysv_delete_inode,
put_super: sysv_put_super,
write_super: sysv_write_super,
statfs: sysv_statfs,
};
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