Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm...

[deliverable/linux.git] / fs / devpts / inode.c

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 655f21f991606b5bf2bef600a54b814994dbed98..0b2954d7172d78e78ac98238dfb7b50c5dccb558 100644 (file)
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -128,6 +128,7 @@ static const match_table_t tokens = {
 struct pts_fs_info {
        struct ida allocated_ptys;
        struct pts_mount_opts mount_opts;
+       struct super_block *sb;
        struct dentry *ptmx_dentry;
 };
 
@@ -358,7 +359,7 @@ static const struct super_operations devpts_sops = {
        .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;
 
@@ -369,6 +370,7 @@ static void *new_pts_fs_info(void)
        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;
 }
@@ -384,7 +386,7 @@ 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();
+       s->s_fs_info = new_pts_fs_info(s);
        if (!s->s_fs_info)
                goto fail;
 
@@ -524,17 +526,14 @@ static struct file_system_type devpts_fs_type = {
  * 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;
        int index;
        int ida_ret;
 
-       if (!sb)
+       if (!fsi)
                return -ENODEV;
 
-       fsi = DEVPTS_SB(sb);
 retry:
        if (!ida_pre_get(&fsi->allocated_ptys, GFP_KERNEL))
                return -ENOMEM;
@@ -564,11 +563,8 @@ retry:
        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--;
@@ -578,21 +574,25 @@ void devpts_kill_index(struct inode *ptmx_inode, int idx)
 /*
  * pty code needs to hold extra references in case of last /dev/tty close
  */
-
-void devpts_add_ref(struct inode *ptmx_inode)
+struct pts_fs_info *devpts_get_ref(struct inode *ptmx_inode, struct file *file)
 {
-       struct super_block *sb = pts_sb_from_inode(ptmx_inode);
+       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);
-       ihold(ptmx_inode);
+       return fsi;
 }
 
-void devpts_del_ref(struct inode *ptmx_inode)
+void devpts_put_ref(struct pts_fs_info *fsi)
 {
-       struct super_block *sb = pts_sb_from_inode(ptmx_inode);
-
-       iput(ptmx_inode);
-       deactivate_super(sb);
+       deactivate_super(fsi->sb);
 }
 
 /**
@@ -604,22 +604,20 @@ void devpts_del_ref(struct inode *ptmx_inode)
  *
  * 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,
-               void *priv)
+struct dentry *devpts_pty_new(struct pts_fs_info *fsi, 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;
-       struct pts_fs_info *fsi;
        struct pts_mount_opts *opts;
        char s[12];
 
-       if (!sb)
+       if (!fsi)
                return ERR_PTR(-ENODEV);
 
+       sb = fsi->sb;
        root = sb->s_root;
-       fsi = DEVPTS_SB(sb);
        opts = &fsi->mount_opts;
 
        inode = new_inode(sb);
@@ -630,25 +628,21 @@ struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index,
        inode->i_uid = opts->setuid ? opts->uid : current_fsuid();
        inode->i_gid = opts->setgid ? opts->gid : current_fsgid();
        inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
-       init_special_inode(inode, S_IFCHR|opts->mode, device);
-       inode->i_private = priv;
+       init_special_inode(inode, S_IFCHR|opts->mode, MKDEV(UNIX98_PTY_SLAVE_MAJOR, index));
 
        sprintf(s, "%d", index);
 
-       inode_lock(d_inode(root));
-
        dentry = d_alloc_name(root, s);
        if (dentry) {
+               dentry->d_fsdata = priv;
                d_add(dentry, inode);
                fsnotify_create(d_inode(root), dentry);
        } else {
                iput(inode);
-               inode = ERR_PTR(-ENOMEM);
+               dentry = ERR_PTR(-ENOMEM);
        }
 
-       inode_unlock(d_inode(root));
-
-       return inode;
+       return dentry;
 }
 
 /**
@@ -657,24 +651,10 @@ struct inode *devpts_pty_new(struct inode *ptmx_inode, dev_t device, int index,
  *
  * Returns whatever was passed as priv in devpts_pty_new for a given inode.
  */
-void *devpts_get_priv(struct inode *pts_inode)
+void *devpts_get_priv(struct dentry *dentry)
 {
-       struct dentry *dentry;
-       void *priv = NULL;
-
-       BUG_ON(pts_inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
-
-       /* Ensure dentry has not been deleted by devpts_pty_kill() */
-       dentry = d_find_alias(pts_inode);
-       if (!dentry)
-               return NULL;
-
-       if (pts_inode->i_sb->s_magic == DEVPTS_SUPER_MAGIC)
-               priv = pts_inode->i_private;
-
-       dput(dentry);
-
-       return priv;
+       WARN_ON_ONCE(dentry->d_sb->s_magic != DEVPTS_SUPER_MAGIC);
+       return dentry->d_fsdata;
 }
 
 /**
@@ -683,24 +663,14 @@ void *devpts_get_priv(struct inode *pts_inode)
  *
  * This is an inverse operation of devpts_pty_new.
  */
-void devpts_pty_kill(struct inode *inode)
+void devpts_pty_kill(struct dentry *dentry)
 {
-       struct super_block *sb = pts_sb_from_inode(inode);
-       struct dentry *root = sb->s_root;
-       struct dentry *dentry;
+       WARN_ON_ONCE(dentry->d_sb->s_magic != DEVPTS_SUPER_MAGIC);
 
-       BUG_ON(inode->i_rdev == MKDEV(TTYAUX_MAJOR, PTMX_MINOR));
-
-       inode_lock(d_inode(root));
-
-       dentry = d_find_alias(inode);
-
-       drop_nlink(inode);
+       dentry->d_fsdata = NULL;
+       drop_nlink(dentry->d_inode);
        d_delete(dentry);
        dput(dentry);   /* d_alloc_name() in devpts_pty_new() */
-       dput(dentry);           /* d_find_alias above */
-
-       inode_unlock(d_inode(root));
 }
 
 static int __init init_devpts_fs(void)