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/* -*- linux-c -*- --------------------------------------------------------- *
*
* linux/fs/devpts/inode.c
*
* Copyright 1998 H. Peter Anvin -- All Rights Reserved
*
* This file is part of the Linux kernel and is made available under
* the terms of the GNU General Public License, version 2, or at your
* option, any later version, incorporated herein by reference.
*
* ------------------------------------------------------------------------- */
#include <linux/module.h>
#include <linux/string.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/kdev_t.h>
#include <linux/kernel.h>
#include <linux/locks.h>
#include <linux/major.h>
#include <linux/slab.h>
#include <linux/stat.h>
#include <linux/tty.h>
#include <asm/bitops.h>
#include <asm/uaccess.h>
#include "devpts_i.h"
static struct vfsmount *devpts_mnt;
static void devpts_put_super(struct super_block *sb)
{
struct devpts_sb_info *sbi = SBI(sb);
struct inode *inode;
int i;
for ( i = 0 ; i < sbi->max_ptys ; i++ ) {
if ( (inode = sbi->inodes[i]) ) {
if ( atomic_read(&inode->i_count) != 1 )
printk("devpts_put_super: badness: entry %d count %d\n",
i, atomic_read(&inode->i_count));
inode->i_nlink--;
iput(inode);
}
}
kfree(sbi->inodes);
kfree(sbi);
}
static int devpts_statfs(struct super_block *sb, struct statfs *buf);
static int devpts_remount (struct super_block * sb, int * flags, char * data);
static struct super_operations devpts_sops = {
put_super: devpts_put_super,
statfs: devpts_statfs,
remount_fs: devpts_remount,
};
static int devpts_parse_options(char *options, struct devpts_sb_info *sbi)
{
int setuid = 0;
int setgid = 0;
uid_t uid = 0;
gid_t gid = 0;
umode_t mode = 0600;
char *this_char, *value;
this_char = NULL;
if ( options )
this_char = strtok(options,",");
for ( ; this_char; this_char = strtok(NULL,",")) {
if ((value = strchr(this_char,'=')) != NULL)
*value++ = 0;
if (!strcmp(this_char,"uid")) {
if (!value || !*value)
return 1;
uid = simple_strtoul(value,&value,0);
if (*value)
return 1;
setuid = 1;
}
else if (!strcmp(this_char,"gid")) {
if (!value || !*value)
return 1;
gid = simple_strtoul(value,&value,0);
if (*value)
return 1;
setgid = 1;
}
else if (!strcmp(this_char,"mode")) {
if (!value || !*value)
return 1;
mode = simple_strtoul(value,&value,8);
if (*value)
return 1;
}
else
return 1;
}
sbi->setuid = setuid;
sbi->setgid = setgid;
sbi->uid = uid;
sbi->gid = gid;
sbi->mode = mode & ~S_IFMT;
return 0;
}
static int devpts_remount(struct super_block * sb, int * flags, char * data)
{
struct devpts_sb_info *sbi = sb->u.generic_sbp;
int res = devpts_parse_options(data,sbi);
if (res) {
printk("devpts: called with bogus options\n");
return -EINVAL;
}
return 0;
}
struct super_block *devpts_read_super(struct super_block *s, void *data,
int silent)
{
struct inode * inode;
struct devpts_sb_info *sbi;
sbi = (struct devpts_sb_info *) kmalloc(sizeof(struct devpts_sb_info), GFP_KERNEL);
if ( !sbi )
goto fail;
sbi->magic = DEVPTS_SBI_MAGIC;
sbi->max_ptys = unix98_max_ptys;
sbi->inodes = kmalloc(sizeof(struct inode *) * sbi->max_ptys, GFP_KERNEL);
if ( !sbi->inodes )
goto fail_free;
memset(sbi->inodes, 0, sizeof(struct inode *) * sbi->max_ptys);
if ( devpts_parse_options(data,sbi) && !silent) {
printk("devpts: called with bogus options\n");
goto fail_free;
}
inode = new_inode(s);
if (!inode)
goto fail_free;
inode->i_ino = 1;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_blocks = 0;
inode->i_blksize = 1024;
inode->i_uid = inode->i_gid = 0;
inode->i_mode = S_IFDIR | S_IRUGO | S_IXUGO | S_IWUSR;
inode->i_op = &devpts_root_inode_operations;
inode->i_fop = &devpts_root_operations;
inode->i_nlink = 2;
s->u.generic_sbp = (void *) sbi;
s->s_blocksize = 1024;
s->s_blocksize_bits = 10;
s->s_magic = DEVPTS_SUPER_MAGIC;
s->s_op = &devpts_sops;
s->s_root = d_alloc_root(inode);
if (s->s_root)
return s;
printk("devpts: get root dentry failed\n");
iput(inode);
fail_free:
kfree(sbi);
fail:
return NULL;
}
static int devpts_statfs(struct super_block *sb, struct statfs *buf)
{
buf->f_type = DEVPTS_SUPER_MAGIC;
buf->f_bsize = 1024;
buf->f_namelen = NAME_MAX;
return 0;
}
static DECLARE_FSTYPE(devpts_fs_type, "devpts", devpts_read_super, FS_SINGLE);
void devpts_pty_new(int number, kdev_t device)
{
struct super_block *sb = devpts_mnt->mnt_sb;
struct devpts_sb_info *sbi = SBI(sb);
struct inode *inode;
if ( sbi->inodes[number] )
return; /* Already registered, this does happen */
inode = new_inode(sb);
if (!inode)
return;
inode->i_ino = number+2;
inode->i_blocks = 0;
inode->i_blksize = 1024;
inode->i_uid = sbi->setuid ? sbi->uid : current->fsuid;
inode->i_gid = sbi->setgid ? sbi->gid : current->fsgid;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
init_special_inode(inode, S_IFCHR|sbi->mode, kdev_t_to_nr(device));
if ( sbi->inodes[number] ) {
iput(inode);
return;
}
sbi->inodes[number] = inode;
}
void devpts_pty_kill(int number)
{
struct super_block *sb = devpts_mnt->mnt_sb;
struct devpts_sb_info *sbi = SBI(sb);
struct inode *inode = sbi->inodes[number];
if ( inode ) {
sbi->inodes[number] = NULL;
inode->i_nlink--;
iput(inode);
}
}
static int __init init_devpts_fs(void)
{
int err = register_filesystem(&devpts_fs_type);
if (!err) {
devpts_mnt = kern_mount(&devpts_fs_type);
err = PTR_ERR(devpts_mnt);
if (!IS_ERR(devpts_mnt))
err = 0;
#ifdef MODULE
if ( !err ) {
devpts_upcall_new = devpts_pty_new;
devpts_upcall_kill = devpts_pty_kill;
}
#endif
}
return err;
}
static void __exit exit_devpts_fs(void)
{
#ifdef MODULE
devpts_upcall_new = NULL;
devpts_upcall_kill = NULL;
#endif
unregister_filesystem(&devpts_fs_type);
kern_umount(devpts_mnt);
}
module_init(init_devpts_fs)
module_exit(exit_devpts_fs)
MODULE_LICENSE("GPL");
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