#define DEVPTS_SUPER_MAGIC 0x1cd1
#define DEVPTS_DEFAULT_MODE 0600
+#define PTMX_MINOR 2
extern int pty_limit; /* Config limit on Unix98 ptys */
-static DEFINE_IDA(allocated_ptys);
static DEFINE_MUTEX(allocated_ptys_lock);
static struct vfsmount *devpts_mnt;
-static struct dentry *devpts_root;
static struct {
int setuid;
Opt_err
};
-static match_table_t tokens = {
+static const match_table_t tokens = {
{Opt_uid, "uid=%u"},
{Opt_gid, "gid=%u"},
{Opt_mode, "mode=%o"},
{Opt_err, NULL}
};
+struct pts_fs_info {
+ struct ida allocated_ptys;
+};
+
+static inline struct pts_fs_info *DEVPTS_SB(struct super_block *sb)
+{
+ return sb->s_fs_info;
+}
+
+static inline struct super_block *pts_sb_from_inode(struct inode *inode)
+{
+ if (inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
+ return inode->i_sb;
+
+ return devpts_mnt->mnt_sb;
+}
+
static int devpts_remount(struct super_block *sb, int *flags, char *data)
{
char *p;
.show_options = devpts_show_options,
};
+static void *new_pts_fs_info(void)
+{
+ struct pts_fs_info *fsi;
+
+ fsi = kzalloc(sizeof(struct pts_fs_info), GFP_KERNEL);
+ if (!fsi)
+ return NULL;
+
+ ida_init(&fsi->allocated_ptys);
+
+ return fsi;
+}
+
static int
devpts_fill_super(struct super_block *s, void *data, int silent)
{
s->s_op = &devpts_sops;
s->s_time_gran = 1;
+ s->s_fs_info = new_pts_fs_info();
+ if (!s->s_fs_info)
+ goto fail;
+
inode = new_inode(s);
if (!inode)
- goto fail;
+ goto free_fsi;
inode->i_ino = 1;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_blocks = 0;
inode->i_fop = &simple_dir_operations;
inode->i_nlink = 2;
- devpts_root = s->s_root = d_alloc_root(inode);
+ s->s_root = d_alloc_root(inode);
if (s->s_root)
return 0;
printk("devpts: get root dentry failed\n");
iput(inode);
+
+free_fsi:
+ kfree(s->s_fs_info);
fail:
return -ENOMEM;
}
return get_sb_single(fs_type, flags, data, devpts_fill_super, mnt);
}
+static void devpts_kill_sb(struct super_block *sb)
+{
+ struct pts_fs_info *fsi = DEVPTS_SB(sb);
+
+ kfree(fsi);
+ kill_anon_super(sb);
+}
+
static struct file_system_type devpts_fs_type = {
.owner = THIS_MODULE,
.name = "devpts",
.get_sb = devpts_get_sb,
- .kill_sb = kill_anon_super,
+ .kill_sb = devpts_kill_sb,
};
/*
* to the System V naming convention
*/
-static struct dentry *get_node(int num)
-{
- char s[12];
- struct dentry *root = devpts_root;
- mutex_lock(&root->d_inode->i_mutex);
- return lookup_one_len(s, root, sprintf(s, "%d", num));
-}
-
int devpts_new_index(struct inode *ptmx_inode)
{
+ struct super_block *sb = pts_sb_from_inode(ptmx_inode);
+ struct pts_fs_info *fsi = DEVPTS_SB(sb);
int index;
int ida_ret;
retry:
- if (!ida_pre_get(&allocated_ptys, GFP_KERNEL)) {
+ if (!ida_pre_get(&fsi->allocated_ptys, GFP_KERNEL)) {
return -ENOMEM;
}
mutex_lock(&allocated_ptys_lock);
- ida_ret = ida_get_new(&allocated_ptys, &index);
+ ida_ret = ida_get_new(&fsi->allocated_ptys, &index);
if (ida_ret < 0) {
mutex_unlock(&allocated_ptys_lock);
if (ida_ret == -EAGAIN)
}
if (index >= pty_limit) {
- ida_remove(&allocated_ptys, index);
+ ida_remove(&fsi->allocated_ptys, index);
mutex_unlock(&allocated_ptys_lock);
return -EIO;
}
void devpts_kill_index(struct inode *ptmx_inode, int idx)
{
+ struct super_block *sb = pts_sb_from_inode(ptmx_inode);
+ struct pts_fs_info *fsi = DEVPTS_SB(sb);
+
mutex_lock(&allocated_ptys_lock);
- ida_remove(&allocated_ptys, idx);
+ ida_remove(&fsi->allocated_ptys, idx);
mutex_unlock(&allocated_ptys_lock);
}
struct tty_driver *driver = tty->driver;
dev_t device = MKDEV(driver->major, driver->minor_start+number);
struct dentry *dentry;
- struct inode *inode = new_inode(devpts_mnt->mnt_sb);
+ struct super_block *sb = pts_sb_from_inode(ptmx_inode);
+ struct inode *inode = new_inode(sb);
+ struct dentry *root = sb->s_root;
+ char s[12];
/* We're supposed to be given the slave end of a pty */
BUG_ON(driver->type != TTY_DRIVER_TYPE_PTY);
return -ENOMEM;
inode->i_ino = number+2;
- inode->i_uid = config.setuid ? config.uid : current->fsuid;
- inode->i_gid = config.setgid ? config.gid : current->fsgid;
+ inode->i_uid = config.setuid ? config.uid : current_fsuid();
+ inode->i_gid = config.setgid ? config.gid : current_fsgid();
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
init_special_inode(inode, S_IFCHR|config.mode, device);
inode->i_private = tty;
+ tty->driver_data = inode;
+
+ sprintf(s, "%d", number);
+
+ mutex_lock(&root->d_inode->i_mutex);
- dentry = get_node(number);
- if (!IS_ERR(dentry) && !dentry->d_inode) {
- d_instantiate(dentry, inode);
- fsnotify_create(devpts_root->d_inode, dentry);
+ dentry = d_alloc_name(root, s);
+ if (!IS_ERR(dentry)) {
+ d_add(dentry, inode);
+ fsnotify_create(root->d_inode, dentry);
}
- mutex_unlock(&devpts_root->d_inode->i_mutex);
+ mutex_unlock(&root->d_inode->i_mutex);
return 0;
}
struct tty_struct *devpts_get_tty(struct inode *pts_inode, int number)
{
- struct dentry *dentry = get_node(number);
- struct tty_struct *tty;
+ BUG_ON(pts_inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
- tty = NULL;
- if (!IS_ERR(dentry)) {
- if (dentry->d_inode)
- tty = dentry->d_inode->i_private;
- dput(dentry);
- }
-
- mutex_unlock(&devpts_root->d_inode->i_mutex);
-
- return tty;
+ if (pts_inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
+ return (struct tty_struct *)pts_inode->i_private;
+ return NULL;
}
void devpts_pty_kill(struct tty_struct *tty)
{
- int number = tty->index;
- struct dentry *dentry = get_node(number);
+ struct inode *inode = tty->driver_data;
+ struct super_block *sb = pts_sb_from_inode(inode);
+ struct dentry *root = sb->s_root;
+ struct dentry *dentry;
- if (!IS_ERR(dentry)) {
- struct inode *inode = dentry->d_inode;
- if (inode) {
- inode->i_nlink--;
- d_delete(dentry);
- dput(dentry);
- }
+ BUG_ON(inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
+
+ mutex_lock(&root->d_inode->i_mutex);
+
+ dentry = d_find_alias(inode);
+ if (dentry && !IS_ERR(dentry)) {
+ inode->i_nlink--;
+ d_delete(dentry);
dput(dentry);
}
- mutex_unlock(&devpts_root->d_inode->i_mutex);
+
+ mutex_unlock(&root->d_inode->i_mutex);
}
static int __init init_devpts_fs(void)
Code Review / linux-2.6.git / blobdiff