diff --git a/include/linux/bpf.h b/include/linux/bpf.h index 34c655cf4759..ad4f53cb9d81 100644 --- a/include/linux/bpf.h +++ b/include/linux/bpf.h @@ -1219,12 +1219,18 @@ typedef int (*bpf_iter_attach_target_t)(struct bpf_prog *prog, union bpf_iter_link_info *linfo, struct bpf_iter_aux_info *aux); typedef void (*bpf_iter_detach_target_t)(struct bpf_iter_aux_info *aux); +typedef void (*bpf_iter_show_fdinfo_t) (const struct bpf_iter_aux_info *aux, + struct seq_file *seq); +typedef int (*bpf_iter_fill_link_info_t)(const struct bpf_iter_aux_info *aux, + struct bpf_link_info *info); #define BPF_ITER_CTX_ARG_MAX 2 struct bpf_iter_reg { const char *target; bpf_iter_attach_target_t attach_target; bpf_iter_detach_target_t detach_target; + bpf_iter_show_fdinfo_t show_fdinfo; + bpf_iter_fill_link_info_t fill_link_info; u32 ctx_arg_info_size; struct bpf_ctx_arg_aux ctx_arg_info[BPF_ITER_CTX_ARG_MAX]; const struct bpf_iter_seq_info *seq_info; diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index accaf824fe33..c2fe59884c3a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -4082,6 +4082,13 @@ struct bpf_link_info { __u64 cgroup_id; __u32 attach_type; } cgroup; + struct { + __aligned_u64 target_name; /* in/out: target_name buffer ptr */ + __u32 target_name_len; /* in/out: target_name buffer len */ + union { + __u32 map_id; + } map; + } iter; struct { __u32 netns_ino; __u32 attach_type; diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c index 8faa2ce89396..30833bbf3019 100644 --- a/kernel/bpf/bpf_iter.c +++ b/kernel/bpf/bpf_iter.c @@ -390,10 +390,68 @@ out_unlock: return ret; } +static void bpf_iter_link_show_fdinfo(const struct bpf_link *link, + struct seq_file *seq) +{ + struct bpf_iter_link *iter_link = + container_of(link, struct bpf_iter_link, link); + bpf_iter_show_fdinfo_t show_fdinfo; + + seq_printf(seq, + "target_name:\t%s\n", + iter_link->tinfo->reg_info->target); + + show_fdinfo = iter_link->tinfo->reg_info->show_fdinfo; + if (show_fdinfo) + show_fdinfo(&iter_link->aux, seq); +} + +static int bpf_iter_link_fill_link_info(const struct bpf_link *link, + struct bpf_link_info *info) +{ + struct bpf_iter_link *iter_link = + container_of(link, struct bpf_iter_link, link); + char __user *ubuf = u64_to_user_ptr(info->iter.target_name); + bpf_iter_fill_link_info_t fill_link_info; + u32 ulen = info->iter.target_name_len; + const char *target_name; + u32 target_len; + + if (!ulen ^ !ubuf) + return -EINVAL; + + target_name = iter_link->tinfo->reg_info->target; + target_len = strlen(target_name); + info->iter.target_name_len = target_len + 1; + + if (ubuf) { + if (ulen >= target_len + 1) { + if (copy_to_user(ubuf, target_name, target_len + 1)) + return -EFAULT; + } else { + char zero = '\0'; + + if (copy_to_user(ubuf, target_name, ulen - 1)) + return -EFAULT; + if (put_user(zero, ubuf + ulen - 1)) + return -EFAULT; + return -ENOSPC; + } + } + + fill_link_info = iter_link->tinfo->reg_info->fill_link_info; + if (fill_link_info) + return fill_link_info(&iter_link->aux, info); + + return 0; +} + static const struct bpf_link_ops bpf_iter_link_lops = { .release = bpf_iter_link_release, .dealloc = bpf_iter_link_dealloc, .update_prog = bpf_iter_link_replace, + .show_fdinfo = bpf_iter_link_show_fdinfo, + .fill_link_info = bpf_iter_link_fill_link_info, }; bool bpf_link_is_iter(struct bpf_link *link) diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index 7ced67a67c94..9f988e7119fc 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -3978,6 +3978,13 @@ struct bpf_link_info { __u64 cgroup_id; __u32 attach_type; } cgroup; + struct { + __aligned_u64 target_name; /* in/out: target_name buffer ptr */ + __u32 target_name_len; /* in/out: target_name buffer len */ + union { + __u32 map_id; + } map; + } iter; struct { __u32 netns_ino; __u32 attach_type;