blob: 0c63bc2cd895a2e5c5b8e6199dae4a9e041a095b [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/init.h>
#include <linux/module.h>
#include "bpf_preload.h"
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
#include "iterators/iterators.lskel-little-endian.h"
#else
#include "iterators/iterators.lskel-big-endian.h"
#endif
static struct bpf_link *maps_link, *progs_link;
static struct iterators_bpf *skel;
static void free_links_and_skel(void)
{
if (!IS_ERR_OR_NULL(maps_link))
bpf_link_put(maps_link);
if (!IS_ERR_OR_NULL(progs_link))
bpf_link_put(progs_link);
iterators_bpf__destroy(skel);
}
static int preload(struct bpf_preload_info *obj)
{
strscpy(obj[0].link_name, "maps.debug", sizeof(obj[0].link_name));
obj[0].link = maps_link;
strscpy(obj[1].link_name, "progs.debug", sizeof(obj[1].link_name));
obj[1].link = progs_link;
return 0;
}
static struct bpf_preload_ops ops = {
.preload = preload,
.owner = THIS_MODULE,
};
static int load_skel(void)
{
int err;
skel = iterators_bpf__open();
if (!skel)
return -ENOMEM;
err = iterators_bpf__load(skel);
if (err)
goto out;
err = iterators_bpf__attach(skel);
if (err)
goto out;
maps_link = bpf_link_get_from_fd(skel->links.dump_bpf_map_fd);
if (IS_ERR(maps_link)) {
err = PTR_ERR(maps_link);
goto out;
}
progs_link = bpf_link_get_from_fd(skel->links.dump_bpf_prog_fd);
if (IS_ERR(progs_link)) {
err = PTR_ERR(progs_link);
goto out;
}
/* Avoid taking over stdin/stdout/stderr of init process. Zeroing out
* makes skel_closenz() a no-op later in iterators_bpf__destroy().
*/
close_fd(skel->links.dump_bpf_map_fd);
skel->links.dump_bpf_map_fd = 0;
close_fd(skel->links.dump_bpf_prog_fd);
skel->links.dump_bpf_prog_fd = 0;
return 0;
out:
free_links_and_skel();
return err;
}
static int __init load(void)
{
int err;
err = load_skel();
if (err)
return err;
bpf_preload_ops = &ops;
return err;
}
static void __exit fini(void)
{
bpf_preload_ops = NULL;
free_links_and_skel();
}
late_initcall(load);
module_exit(fini);
MODULE_LICENSE("GPL");