video: rockchip: iep: add drm support

[firefly-linux-kernel-4.4.55.git] / fs / devpts / inode.c

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index c35ffdc12bbafd1874dcea43ec5094867daf3e0d..c82edb0491170dffe131aefab27e2cb2e5d6c982 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;
@@ -564,17 +563,38 @@ 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--;
        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
@@ -584,22 +604,21 @@ void devpts_kill_index(struct inode *ptmx_inode, int idx)
  *
  * 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;
-       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);