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@@ -322,85 +322,38 @@ static int compare_init_pts_sb(struct super_block *s, void *p)
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}
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/*
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- * Mount a new (private) instance of devpts. PTYs created in this
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- * instance are independent of the PTYs in other devpts instances.
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- */
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-static int new_pts_mount(struct file_system_type *fs_type, int flags,
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- void *data, struct pts_mount_opts *opts, struct vfsmount *mnt)
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-{
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- int err;
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- struct pts_fs_info *fsi;
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-
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- err = get_sb_nodev(fs_type, flags, data, devpts_fill_super, mnt);
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- if (err)
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- return err;
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-
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- fsi = DEVPTS_SB(mnt->mnt_sb);
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- memcpy(&fsi->mount_opts, opts, sizeof(opts));
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-
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- return 0;
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-}
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-
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-/*
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- * init_pts_mount()
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+ * devpts_get_sb()
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+ *
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+ * If the '-o newinstance' mount option was specified, mount a new
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+ * (private) instance of devpts. PTYs created in this instance are
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+ * independent of the PTYs in other devpts instances.
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+ *
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+ * If the '-o newinstance' option was not specified, mount/remount the
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+ * initial kernel mount of devpts. This type of mount gives the
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+ * legacy, single-instance semantics.
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*
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- * Mount or remount the initial kernel mount of devpts. This type of
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- * mount maintains the legacy, single-instance semantics, while the
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- * kernel still allows multiple-instances.
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+ * The 'newinstance' option is needed to support multiple namespace
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+ * semantics in devpts while preserving backward compatibility of the
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+ * current 'single-namespace' semantics. i.e all mounts of devpts
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+ * without the 'newinstance' mount option should bind to the initial
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+ * kernel mount, like get_sb_single().
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*
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- * This interface is needed to support multiple namespace semantics in
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- * devpts while preserving backward compatibility of the current 'single-
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- * namespace' semantics. i.e all mounts of devpts without the 'newinstance'
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- * mount option should bind to the initial kernel mount, like
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- * get_sb_single().
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+ * Mounts with 'newinstance' option create a new, private namespace.
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*
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- * Mounts with 'newinstance' option create a new private namespace.
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+ * NOTE:
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*
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- * But for single-mount semantics, devpts cannot use get_sb_single(),
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+ * For single-mount semantics, devpts cannot use get_sb_single(),
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* because get_sb_single()/sget() find and use the super-block from
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* the most recent mount of devpts. But that recent mount may be a
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* 'newinstance' mount and get_sb_single() would pick the newinstance
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* super-block instead of the initial super-block.
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- *
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- * This interface is identical to get_sb_single() except that it
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- * consistently selects the 'single-namespace' superblock even in the
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- * presence of the private namespace (i.e 'newinstance') super-blocks.
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*/
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-static int init_pts_mount(struct file_system_type *fs_type, int flags,
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- void *data, struct pts_mount_opts *opts, struct vfsmount *mnt)
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-{
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- struct super_block *s;
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- struct pts_fs_info *fsi;
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- int error;
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-
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- s = sget(fs_type, compare_init_pts_sb, set_anon_super, NULL);
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- if (IS_ERR(s))
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- return PTR_ERR(s);
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-
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- if (!s->s_root) {
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- s->s_flags = flags;
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- error = devpts_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
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- if (error) {
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- up_write(&s->s_umount);
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- deactivate_super(s);
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- return error;
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- }
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- s->s_flags |= MS_ACTIVE;
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- }
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-
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- simple_set_mnt(mnt, s);
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-
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- fsi = DEVPTS_SB(mnt->mnt_sb);
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- memcpy(&fsi->mount_opts, opts, sizeof(opts));
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-
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- return 0;
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-}
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-
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static int devpts_get_sb(struct file_system_type *fs_type,
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int flags, const char *dev_name, void *data, struct vfsmount *mnt)
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{
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int error;
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struct pts_mount_opts opts;
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+ struct super_block *s;
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memset(&opts, 0, sizeof(opts));
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if (data) {
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@@ -410,23 +363,37 @@ static int devpts_get_sb(struct file_system_type *fs_type,
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}
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if (opts.newinstance)
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- error = new_pts_mount(fs_type, flags, data, &opts, mnt);
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+ s = sget(fs_type, NULL, set_anon_super, NULL);
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else
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- error = init_pts_mount(fs_type, flags, data, &opts, mnt);
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+ s = sget(fs_type, compare_init_pts_sb, set_anon_super, NULL);
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- if (error)
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- return error;
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+ if (IS_ERR(s))
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+ return PTR_ERR(s);
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+
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+ if (!s->s_root) {
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+ s->s_flags = flags;
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+ error = devpts_fill_super(s, data, flags & MS_SILENT ? 1 : 0);
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+ if (error)
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+ goto out_undo_sget;
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+ s->s_flags |= MS_ACTIVE;
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+ }
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+
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+ simple_set_mnt(mnt, s);
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+
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+ memcpy(&(DEVPTS_SB(s))->mount_opts, &opts, sizeof(opts));
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- error = mknod_ptmx(mnt->mnt_sb);
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+ error = mknod_ptmx(s);
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if (error)
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goto out_dput;
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return 0;
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out_dput:
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- dput(mnt->mnt_sb->s_root);
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- up_write(&mnt->mnt_sb->s_umount);
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- deactivate_super(mnt->mnt_sb);
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+ dput(s->s_root);
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+
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+out_undo_sget:
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+ up_write(&s->s_umount);
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+ deactivate_super(s);
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return error;
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}
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