object creation goes through the normal VFS paths or approximation thereof (user_path_create()/done_path_create() in case of bpf_obj_do_pin(), open-coded simple_{start,done}_creating() in bpf_iter_link_pin_kernel() at mount time), removals go entirely through the normal VFS paths (and ->unlink() is simple_unlink() there). Enough to have bpf_dentry_finalize() use d_make_persistent() instead of dget() and we are done. Convert bpf_iter_link_pin_kernel() to simple_{start,done}_creating(), while we are at it. Signed-off-by: Al Viro --- kernel/bpf/inode.c | 15 +++++---------- 1 file changed, 5 insertions(+), 10 deletions(-) diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index 81780bcf8d25..9f866a010dad 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -144,8 +144,7 @@ static int bpf_inode_type(const struct inode *inode, enum bpf_type *type) static void bpf_dentry_finalize(struct dentry *dentry, struct inode *inode, struct inode *dir) { - d_instantiate(dentry, inode); - dget(dentry); + d_make_persistent(dentry, inode); inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); } @@ -420,16 +419,12 @@ static int bpf_iter_link_pin_kernel(struct dentry *parent, struct dentry *dentry; int ret; - inode_lock(parent->d_inode); - dentry = lookup_noperm(&QSTR(name), parent); - if (IS_ERR(dentry)) { - inode_unlock(parent->d_inode); + dentry = simple_start_creating(parent, name); + if (IS_ERR(dentry)) return PTR_ERR(dentry); - } ret = bpf_mkobj_ops(dentry, mode, link, &bpf_link_iops, &bpf_iter_fops); - dput(dentry); - inode_unlock(parent->d_inode); + simple_done_creating(dentry); return ret; } @@ -1080,7 +1075,7 @@ static void bpf_kill_super(struct super_block *sb) { struct bpf_mount_opts *opts = sb->s_fs_info; - kill_litter_super(sb); + kill_anon_super(sb); kfree(opts); } -- 2.47.3