From 909e6d94795654040ed416ac69858d5d2ce66dd3 Mon Sep 17 00:00:00 2001 From: "Serge E. Hallyn" Date: Mon, 6 Apr 2009 19:01:07 -0700 Subject: [PATCH] namespaces: move proc_net_get_sb to a generic fs/super.c helper The mqueuefs filesystem will use this helper as well. Proc's main get_sb could also be made to use it, but that will require a bit more rework. Signed-off-by: Serge E. Hallyn Cc: Cedric Le Goater Cc: Alexey Dobriyan Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/super.c | 40 ++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 3 +++ 2 files changed, 43 insertions(+) diff --git a/fs/super.c b/fs/super.c index 77cb4ec..786fe7d 100644 --- a/fs/super.c +++ b/fs/super.c @@ -771,6 +771,46 @@ void kill_litter_super(struct super_block *sb) EXPORT_SYMBOL(kill_litter_super); +static int ns_test_super(struct super_block *sb, void *data) +{ + return sb->s_fs_info == data; +} + +static int ns_set_super(struct super_block *sb, void *data) +{ + sb->s_fs_info = data; + return set_anon_super(sb, NULL); +} + +int get_sb_ns(struct file_system_type *fs_type, int flags, void *data, + int (*fill_super)(struct super_block *, void *, int), + struct vfsmount *mnt) +{ + struct super_block *sb; + + sb = sget(fs_type, ns_test_super, ns_set_super, data); + if (IS_ERR(sb)) + return PTR_ERR(sb); + + if (!sb->s_root) { + int err; + sb->s_flags = flags; + err = fill_super(sb, data, flags & MS_SILENT ? 1 : 0); + if (err) { + up_write(&sb->s_umount); + deactivate_super(sb); + return err; + } + + sb->s_flags |= MS_ACTIVE; + } + + simple_set_mnt(mnt, sb); + return 0; +} + +EXPORT_SYMBOL(get_sb_ns); + #ifdef CONFIG_BLOCK static int set_bdev_super(struct super_block *s, void *data) { diff --git a/include/linux/fs.h b/include/linux/fs.h index bce40a2..562d285 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1699,6 +1699,9 @@ struct file_system_type { struct lock_class_key i_alloc_sem_key; }; +extern int get_sb_ns(struct file_system_type *fs_type, int flags, void *data, + int (*fill_super)(struct super_block *, void *, int), + struct vfsmount *mnt); extern int get_sb_bdev(struct file_system_type *fs_type, int flags, const char *dev_name, void *data, int (*fill_super)(struct super_block *, void *, int), -- 1.8.2.3