From e1a91586d5da6f879b6dd385a2e7227bf1653570 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 23 Dec 2018 16:25:31 -0500 Subject: fs_context flavour for submounts This is an eventual replacement for vfs_submount() uses. Unlike the "mount" and "remount" cases, the users of that thing are not in VFS - they are buried in various ->d_automount() instances and rather than converting them all at once we introduce the (thankfully small and simple) infrastructure here and deal with the prospective users in afs, nfs, etc. parts of the series. Here we just introduce a new constructor (fs_context_for_submount()) along with the corresponding enum constant to be put into fc->purpose for those. Signed-off-by: Al Viro --- fs/fs_context.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'fs/fs_context.c') diff --git a/fs/fs_context.c b/fs/fs_context.c index 5e2c3aba1dd8..2bd652b6e848 100644 --- a/fs/fs_context.c +++ b/fs/fs_context.c @@ -69,6 +69,9 @@ static struct fs_context *alloc_fs_context(struct file_system_type *fs_type, case FS_CONTEXT_FOR_MOUNT: fc->user_ns = get_user_ns(fc->cred->user_ns); break; + case FS_CONTEXT_FOR_SUBMOUNT: + fc->user_ns = get_user_ns(reference->d_sb->s_user_ns); + break; case FS_CONTEXT_FOR_RECONFIGURE: /* We don't pin any namespaces as the superblock's * subscriptions cannot be changed at this point. @@ -106,6 +109,13 @@ struct fs_context *fs_context_for_reconfigure(struct dentry *dentry, } EXPORT_SYMBOL(fs_context_for_reconfigure); +struct fs_context *fs_context_for_submount(struct file_system_type *type, + struct dentry *reference) +{ + return alloc_fs_context(type, reference, 0, 0, FS_CONTEXT_FOR_SUBMOUNT); +} +EXPORT_SYMBOL(fs_context_for_submount); + void fc_drop_locked(struct fs_context *fc) { struct super_block *sb = fc->root->d_sb; -- cgit v1.2.3-59-g8ed1b