73 lines
1.7 KiB
C
73 lines
1.7 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
/* Copyright (c) 2022 Meta Platforms, Inc. and affiliates. */
|
||
|
|
|
||
|
|
#ifndef _CGRP_KFUNC_COMMON_H
|
||
|
|
#define _CGRP_KFUNC_COMMON_H
|
||
|
|
|
||
|
|
#include <errno.h>
|
||
|
|
#include <vmlinux.h>
|
||
|
|
#include <bpf/bpf_helpers.h>
|
||
|
|
#include <bpf/bpf_tracing.h>
|
||
|
|
|
||
|
|
struct __cgrps_kfunc_map_value {
|
||
|
|
struct cgroup __kptr_ref * cgrp;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct hash_map {
|
||
|
|
__uint(type, BPF_MAP_TYPE_HASH);
|
||
|
|
__type(key, int);
|
||
|
|
__type(value, struct __cgrps_kfunc_map_value);
|
||
|
|
__uint(max_entries, 1);
|
||
|
|
} __cgrps_kfunc_map SEC(".maps");
|
||
|
|
|
||
|
|
struct cgroup *bpf_cgroup_acquire(struct cgroup *p) __ksym;
|
||
|
|
struct cgroup *bpf_cgroup_kptr_get(struct cgroup **pp) __ksym;
|
||
|
|
void bpf_cgroup_release(struct cgroup *p) __ksym;
|
||
|
|
struct cgroup *bpf_cgroup_ancestor(struct cgroup *cgrp, int level) __ksym;
|
||
|
|
|
||
|
|
static inline struct __cgrps_kfunc_map_value *cgrps_kfunc_map_value_lookup(struct cgroup *cgrp)
|
||
|
|
{
|
||
|
|
s32 id;
|
||
|
|
long status;
|
||
|
|
|
||
|
|
status = bpf_probe_read_kernel(&id, sizeof(id), &cgrp->self.id);
|
||
|
|
if (status)
|
||
|
|
return NULL;
|
||
|
|
|
||
|
|
return bpf_map_lookup_elem(&__cgrps_kfunc_map, &id);
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline int cgrps_kfunc_map_insert(struct cgroup *cgrp)
|
||
|
|
{
|
||
|
|
struct __cgrps_kfunc_map_value local, *v;
|
||
|
|
long status;
|
||
|
|
struct cgroup *acquired, *old;
|
||
|
|
s32 id;
|
||
|
|
|
||
|
|
status = bpf_probe_read_kernel(&id, sizeof(id), &cgrp->self.id);
|
||
|
|
if (status)
|
||
|
|
return status;
|
||
|
|
|
||
|
|
local.cgrp = NULL;
|
||
|
|
status = bpf_map_update_elem(&__cgrps_kfunc_map, &id, &local, BPF_NOEXIST);
|
||
|
|
if (status)
|
||
|
|
return status;
|
||
|
|
|
||
|
|
v = bpf_map_lookup_elem(&__cgrps_kfunc_map, &id);
|
||
|
|
if (!v) {
|
||
|
|
bpf_map_delete_elem(&__cgrps_kfunc_map, &id);
|
||
|
|
return -ENOENT;
|
||
|
|
}
|
||
|
|
|
||
|
|
acquired = bpf_cgroup_acquire(cgrp);
|
||
|
|
old = bpf_kptr_xchg(&v->cgrp, acquired);
|
||
|
|
if (old) {
|
||
|
|
bpf_cgroup_release(old);
|
||
|
|
return -EEXIST;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* _CGRP_KFUNC_COMMON_H */
|