bpf: Convert bpf_preload.ko to use light skeleton.

[linux-2.6-microblaze.git] / kernel / bpf / preload / bpf_preload_kern.c

diff --git a/kernel/bpf/preload/bpf_preload_kern.c b/kernel/bpf/preload/bpf_preload_kern.c
index 53736e5..30207c0 100644 (file)
--- a/kernel/bpf/preload/bpf_preload_kern.c
+++ b/kernel/bpf/preload/bpf_preload_kern.c
@@ -2,101 +2,80 @@
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/init.h>
 #include <linux/module.h>
-#include <linux/pid.h>
-#include <linux/fs.h>
-#include <linux/sched/signal.h>
 #include "bpf_preload.h"
+#include "iterators/iterators.lskel.h"
 
-extern char bpf_preload_umd_start;
-extern char bpf_preload_umd_end;
+static struct bpf_link *maps_link, *progs_link;
+static struct iterators_bpf *skel;
 
-static int preload(struct bpf_preload_info *obj);
-static int finish(void);
+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)
+{
+       strlcpy(obj[0].link_name, "maps.debug", sizeof(obj[0].link_name));
+       obj[0].link = maps_link;
+       strlcpy(obj[1].link_name, "progs.debug", sizeof(obj[1].link_name));
+       obj[1].link = progs_link;
+       return 0;
+}
 
-static struct bpf_preload_ops umd_ops = {
-       .info.driver_name = "bpf_preload",
+static struct bpf_preload_ops ops = {
        .preload = preload,
-       .finish = finish,
        .owner = THIS_MODULE,
 };
 
-static int preload(struct bpf_preload_info *obj)
+static int load_skel(void)
 {
-       int magic = BPF_PRELOAD_START;
-       loff_t pos = 0;
-       int i, err;
-       ssize_t n;
+       int err;
 
-       err = fork_usermode_driver(&umd_ops.info);
+       skel = iterators_bpf__open();
+       if (!skel)
+               return -ENOMEM;
+       err = iterators_bpf__load(skel);
        if (err)
-               return err;
-
-       /* send the start magic to let UMD proceed with loading BPF progs */
-       n = kernel_write(umd_ops.info.pipe_to_umh,
-                        &magic, sizeof(magic), &pos);
-       if (n != sizeof(magic))
-               return -EPIPE;
-
-       /* receive bpf_link IDs and names from UMD */
-       pos = 0;
-       for (i = 0; i < BPF_PRELOAD_LINKS; i++) {
-               n = kernel_read(umd_ops.info.pipe_from_umh,
-                               &obj[i], sizeof(*obj), &pos);
-               if (n != sizeof(*obj))
-                       return -EPIPE;
+               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;
        }
-       return 0;
-}
-
-static int finish(void)
-{
-       int magic = BPF_PRELOAD_END;
-       struct pid *tgid;
-       loff_t pos = 0;
-       ssize_t n;
-
-       /* send the last magic to UMD. It will do a normal exit. */
-       n = kernel_write(umd_ops.info.pipe_to_umh,
-                        &magic, sizeof(magic), &pos);
-       if (n != sizeof(magic))
-               return -EPIPE;
-
-       tgid = umd_ops.info.tgid;
-       if (tgid) {
-               wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
-               umd_cleanup_helper(&umd_ops.info);
+       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;
        }
        return 0;
+out:
+       free_links_and_skel();
+       return err;
 }
 
-static int __init load_umd(void)
+static int __init load(void)
 {
        int err;
 
-       err = umd_load_blob(&umd_ops.info, &bpf_preload_umd_start,
-                           &bpf_preload_umd_end - &bpf_preload_umd_start);
+       err = load_skel();
        if (err)
                return err;
-       bpf_preload_ops = &umd_ops;
+       bpf_preload_ops = &ops;
        return err;
 }
 
-static void __exit fini_umd(void)
+static void __exit fini(void)
 {
-       struct pid *tgid;
-
        bpf_preload_ops = NULL;
-
-       /* kill UMD in case it's still there due to earlier error */
-       tgid = umd_ops.info.tgid;
-       if (tgid) {
-               kill_pid(tgid, SIGKILL, 1);
-
-               wait_event(tgid->wait_pidfd, thread_group_exited(tgid));
-               umd_cleanup_helper(&umd_ops.info);
-       }
-       umd_unload_blob(&umd_ops.info);
+       free_links_and_skel();
 }
-late_initcall(load_umd);
-module_exit(fini_umd);
+late_initcall(load);
+module_exit(fini);
 MODULE_LICENSE("GPL");