*
* ------------------------------------------------------------------------- */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
struct pts_fs_info {
struct ida allocated_ptys;
struct pts_mount_opts mount_opts;
+ struct super_block *sb;
struct dentry *ptmx_dentry;
};
if (inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
return inode->i_sb;
#endif
+ if (!devpts_mnt)
+ return NULL;
return devpts_mnt->mnt_sb;
}
/*
* parse_mount_options():
- * Set @opts to mount options specified in @data. If an option is not
- * specified in @data, set it to its default value. The exception is
- * 'newinstance' option which can only be set/cleared on a mount (i.e.
- * cannot be changed during remount).
+ * Set @opts to mount options specified in @data. If an option is not
+ * specified in @data, set it to its default value. The exception is
+ * 'newinstance' option which can only be set/cleared on a mount (i.e.
+ * cannot be changed during remount).
*
* Note: @data may be NULL (in which case all options are set to default).
*/
break;
#endif
default:
- printk(KERN_ERR "devpts: called with bogus options\n");
+ pr_err("called with bogus options\n");
return -EINVAL;
}
}
if (!uid_valid(root_uid) || !gid_valid(root_gid))
return -EINVAL;
- mutex_lock(&root->d_inode->i_mutex);
+ mutex_lock(&d_inode(root)->i_mutex);
/* If we have already created ptmx node, return */
if (fsi->ptmx_dentry) {
dentry = d_alloc_name(root, "ptmx");
if (!dentry) {
- printk(KERN_NOTICE "Unable to alloc dentry for ptmx node\n");
+ pr_err("Unable to alloc dentry for ptmx node\n");
goto out;
}
*/
inode = new_inode(sb);
if (!inode) {
- printk(KERN_ERR "Unable to alloc inode for ptmx node\n");
+ pr_err("Unable to alloc inode for ptmx node\n");
dput(dentry);
goto out;
}
fsi->ptmx_dentry = dentry;
rc = 0;
out:
- mutex_unlock(&root->d_inode->i_mutex);
+ mutex_unlock(&d_inode(root)->i_mutex);
return rc;
}
{
struct inode *inode;
if (fsi->ptmx_dentry) {
- inode = fsi->ptmx_dentry->d_inode;
+ inode = d_inode(fsi->ptmx_dentry);
inode->i_mode = S_IFCHR|fsi->mount_opts.ptmxmode;
}
}
#else
static inline void update_ptmx_mode(struct pts_fs_info *fsi)
{
- return;
+ return;
}
#endif
struct pts_mount_opts *opts = &fsi->mount_opts;
if (opts->setuid)
- seq_printf(seq, ",uid=%u", from_kuid_munged(&init_user_ns, opts->uid));
+ seq_printf(seq, ",uid=%u",
+ from_kuid_munged(&init_user_ns, opts->uid));
if (opts->setgid)
- seq_printf(seq, ",gid=%u", from_kgid_munged(&init_user_ns, opts->gid));
+ seq_printf(seq, ",gid=%u",
+ from_kgid_munged(&init_user_ns, opts->gid));
seq_printf(seq, ",mode=%03o", opts->mode);
#ifdef CONFIG_DEVPTS_MULTIPLE_INSTANCES
seq_printf(seq, ",ptmxmode=%03o", opts->ptmxmode);
.show_options = devpts_show_options,
};
-static void *new_pts_fs_info(void)
+static void *new_pts_fs_info(struct super_block *sb)
{
struct pts_fs_info *fsi;
ida_init(&fsi->allocated_ptys);
fsi->mount_opts.mode = DEVPTS_DEFAULT_MODE;
fsi->mount_opts.ptmxmode = DEVPTS_DEFAULT_PTMX_MODE;
+ fsi->sb = sb;
return fsi;
}
s->s_op = &devpts_sops;
s->s_time_gran = 1;
- s->s_fs_info = new_pts_fs_info();
+ s->s_fs_info = new_pts_fs_info(s);
if (!s->s_fs_info)
goto fail;
if (s->s_root)
return 0;
- printk(KERN_ERR "devpts: get root dentry failed\n");
+ pr_err("get root dentry failed\n");
fail:
return -ENOMEM;
* to the System V naming convention
*/
-int devpts_new_index(struct inode *ptmx_inode)
+int devpts_new_index(struct pts_fs_info *fsi)
{
- struct super_block *sb = pts_sb_from_inode(ptmx_inode);
- struct pts_fs_info *fsi = DEVPTS_SB(sb);
int index;
int ida_ret;
+ if (!fsi)
+ return -ENODEV;
+
retry:
if (!ida_pre_get(&fsi->allocated_ptys, GFP_KERNEL))
return -ENOMEM;
return index;
}
-void devpts_kill_index(struct inode *ptmx_inode, int idx)
+void devpts_kill_index(struct pts_fs_info *fsi, 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(&fsi->allocated_ptys, idx);
pty_count--;
mutex_unlock(&allocated_ptys_lock);
}
+/*
+ * pty code needs to hold extra references in case of last /dev/tty close
+ */
+struct pts_fs_info *devpts_get_ref(struct inode *ptmx_inode, struct file *file)
+{
+ struct super_block *sb;
+ struct pts_fs_info *fsi;
+
+ sb = pts_sb_from_inode(ptmx_inode);
+ if (!sb)
+ return NULL;
+ fsi = DEVPTS_SB(sb);
+ if (!fsi)
+ return NULL;
+
+ atomic_inc(&sb->s_active);
+ return fsi;
+}
+
+void devpts_put_ref(struct pts_fs_info *fsi)
+{
+ deactivate_super(fsi->sb);
+}
+
/**
* devpts_pty_new -- create a new inode in /dev/pts/
* @ptmx_inode: inode of the master
*
* The created inode is returned. Remove it from /dev/pts/ by devpts_pty_kill.
*/
-struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index,
+struct inode *devpts_pty_new(struct pts_fs_info *fsi, dev_t device, int index,
void *priv)
{
struct dentry *dentry;
- struct super_block *sb = pts_sb_from_inode(ptmx_inode);
+ struct super_block *sb;
struct inode *inode;
- struct dentry *root = sb->s_root;
- struct pts_fs_info *fsi = DEVPTS_SB(sb);
- struct pts_mount_opts *opts = &fsi->mount_opts;
+ struct dentry *root;
+ struct pts_mount_opts *opts;
char s[12];
+ if (!fsi)
+ return ERR_PTR(-ENODEV);
+
+ sb = fsi->sb;
+ root = sb->s_root;
+ opts = &fsi->mount_opts;
+
inode = new_inode(sb);
if (!inode)
return ERR_PTR(-ENOMEM);
sprintf(s, "%d", index);
- mutex_lock(&root->d_inode->i_mutex);
+ mutex_lock(&d_inode(root)->i_mutex);
dentry = d_alloc_name(root, s);
if (dentry) {
d_add(dentry, inode);
- fsnotify_create(root->d_inode, dentry);
+ fsnotify_create(d_inode(root), dentry);
} else {
iput(inode);
inode = ERR_PTR(-ENOMEM);
}
- mutex_unlock(&root->d_inode->i_mutex);
+ mutex_unlock(&d_inode(root)->i_mutex);
return inode;
}
BUG_ON(inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
- mutex_lock(&root->d_inode->i_mutex);
+ mutex_lock(&d_inode(root)->i_mutex);
dentry = d_find_alias(inode);
dput(dentry); /* d_alloc_name() in devpts_pty_new() */
dput(dentry); /* d_find_alias above */
- mutex_unlock(&root->d_inode->i_mutex);
+ mutex_unlock(&d_inode(root)->i_mutex);
}
static int __init init_devpts_fs(void)
struct ctl_table_header *table;
if (!err) {
+ struct vfsmount *mnt;
+
table = register_sysctl_table(pty_root_table);
- devpts_mnt = kern_mount(&devpts_fs_type);
- if (IS_ERR(devpts_mnt)) {
- err = PTR_ERR(devpts_mnt);
+ mnt = kern_mount(&devpts_fs_type);
+ if (IS_ERR(mnt)) {
+ err = PTR_ERR(mnt);
unregister_filesystem(&devpts_fs_type);
unregister_sysctl_table(table);
+ } else {
+ devpts_mnt = mnt;
}
}
return err;
projects / firefly-linux-kernel-4.4.55.git / blobdiff