bpf: Append _recur naming to the bpf_task_storage helper proto

This patch adds the "_recur" naming to the bpf_task_storage_{get,delete}
proto.  In a latter patch, they will only be used by the tracing
programs that requires a deadlock detection because a tracing
prog may use bpf_task_storage_{get,delete} recursively and cause a
deadlock.

Another following patch will add a different helper proto for the non
tracing programs because they do not need the deadlock prevention.
This patch does this rename to prepare for this future proto
additions.

Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20221025184524.3526117-3-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 1279e69..b04fe3f 100644 (file)
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2519,8 +2519,8 @@ extern const struct bpf_func_proto bpf_this_cpu_ptr_proto;
 extern const struct bpf_func_proto bpf_ktime_get_coarse_ns_proto;
 extern const struct bpf_func_proto bpf_sock_from_file_proto;
 extern const struct bpf_func_proto bpf_get_socket_ptr_cookie_proto;
-extern const struct bpf_func_proto bpf_task_storage_get_proto;
-extern const struct bpf_func_proto bpf_task_storage_delete_proto;
+extern const struct bpf_func_proto bpf_task_storage_get_recur_proto;
+extern const struct bpf_func_proto bpf_task_storage_delete_recur_proto;
 extern const struct bpf_func_proto bpf_for_each_map_elem_proto;
 extern const struct bpf_func_proto bpf_btf_find_by_name_kind_proto;
 extern const struct bpf_func_proto bpf_sk_setsockopt_proto;

diff --git a/kernel/bpf/bpf_task_storage.c b/kernel/bpf/bpf_task_storage.c
index 6f29062..bce50ae 100644 (file)
--- a/kernel/bpf/bpf_task_storage.c
+++ b/kernel/bpf/bpf_task_storage.c
@@ -228,7 +228,7 @@ out:
 }
 
 /* *gfp_flags* is a hidden argument provided by the verifier */
-BPF_CALL_5(bpf_task_storage_get, struct bpf_map *, map, struct task_struct *,
+BPF_CALL_5(bpf_task_storage_get_recur, struct bpf_map *, map, struct task_struct *,
           task, void *, value, u64, flags, gfp_t, gfp_flags)
 {
        struct bpf_local_storage_data *sdata;
@@ -260,7 +260,7 @@ unlock:
                (unsigned long)sdata->data;
 }
 
-BPF_CALL_2(bpf_task_storage_delete, struct bpf_map *, map, struct task_struct *,
+BPF_CALL_2(bpf_task_storage_delete_recur, struct bpf_map *, map, struct task_struct *,
           task)
 {
        int ret;
@@ -322,8 +322,8 @@ const struct bpf_map_ops task_storage_map_ops = {
        .map_owner_storage_ptr = task_storage_ptr,
 };
 
-const struct bpf_func_proto bpf_task_storage_get_proto = {
-       .func = bpf_task_storage_get,
+const struct bpf_func_proto bpf_task_storage_get_recur_proto = {
+       .func = bpf_task_storage_get_recur,
        .gpl_only = false,
        .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
        .arg1_type = ARG_CONST_MAP_PTR,
@@ -333,8 +333,8 @@ const struct bpf_func_proto bpf_task_storage_get_proto = {
        .arg4_type = ARG_ANYTHING,
 };
 
-const struct bpf_func_proto bpf_task_storage_delete_proto = {
-       .func = bpf_task_storage_delete,
+const struct bpf_func_proto bpf_task_storage_delete_recur_proto = {
+       .func = bpf_task_storage_delete_recur,
        .gpl_only = false,
        .ret_type = RET_INTEGER,
        .arg1_type = ARG_CONST_MAP_PTR,

diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 2460e38..83b9b9a 100644 (file)
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1488,9 +1488,9 @@ bpf_tracing_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
        case BPF_FUNC_this_cpu_ptr:
                return &bpf_this_cpu_ptr_proto;
        case BPF_FUNC_task_storage_get:
-               return &bpf_task_storage_get_proto;
+               return &bpf_task_storage_get_recur_proto;
        case BPF_FUNC_task_storage_delete:
-               return &bpf_task_storage_delete_proto;
+               return &bpf_task_storage_delete_recur_proto;
        case BPF_FUNC_for_each_map_elem:
                return &bpf_for_each_map_elem_proto;
        case BPF_FUNC_snprintf: