Implement bpf_wq_set_callback() with an implicit bpf_prog_aux argument, and change bpf_wq_set_callback_impl() to call the new kfunc. Update special kfunc checks in the verifier to accept both versions of the function. In the selftests, a bpf_wq_set_callback_impl() call is intentionally introduced to confirm that both signatures are handled correctly. Signed-off-by: Ihor Solodrai --- kernel/bpf/helpers.c | 18 +++++++++++++----- kernel/bpf/verifier.c | 15 +++++++++------ tools/testing/selftests/bpf/bpf_experimental.h | 5 ----- tools/testing/selftests/bpf/progs/wq.c | 2 +- .../testing/selftests/bpf/progs/wq_failures.c | 4 ++-- 5 files changed, 25 insertions(+), 19 deletions(-) diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 9eaa4185e0a7..23aa785c0f99 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -3120,12 +3120,11 @@ __bpf_kfunc int bpf_wq_start(struct bpf_wq *wq, unsigned int flags) return 0; } -__bpf_kfunc int bpf_wq_set_callback_impl(struct bpf_wq *wq, - int (callback_fn)(void *map, int *key, void *value), - unsigned int flags, - void *aux__prog) +__bpf_kfunc int bpf_wq_set_callback(struct bpf_wq *wq, + int (callback_fn)(void *map, int *key, void *value), + unsigned int flags, + struct bpf_prog_aux *aux) { - struct bpf_prog_aux *aux = (struct bpf_prog_aux *)aux__prog; struct bpf_async_kern *async = (struct bpf_async_kern *)wq; if (flags) @@ -3134,6 +3133,14 @@ __bpf_kfunc int bpf_wq_set_callback_impl(struct bpf_wq *wq, return __bpf_async_set_callback(async, callback_fn, aux, flags, BPF_ASYNC_TYPE_WQ); } +__bpf_kfunc int bpf_wq_set_callback_impl(struct bpf_wq *wq, + int (callback_fn)(void *map, int *key, void *value), + unsigned int flags, + void *aux__prog) +{ + return bpf_wq_set_callback(wq, callback_fn, flags, aux__prog); +} + __bpf_kfunc void bpf_preempt_disable(void) { preempt_disable(); @@ -4488,6 +4495,7 @@ BTF_ID_FLAGS(func, bpf_dynptr_memset) BTF_ID_FLAGS(func, bpf_modify_return_test_tp) #endif BTF_ID_FLAGS(func, bpf_wq_init) +BTF_ID_FLAGS(func, bpf_wq_set_callback, KF_IMPLICIT_ARGS) BTF_ID_FLAGS(func, bpf_wq_set_callback_impl) BTF_ID_FLAGS(func, bpf_wq_start) BTF_ID_FLAGS(func, bpf_preempt_disable) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 5541ab674e30..e5aeee554377 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -520,7 +520,7 @@ static bool is_async_callback_calling_kfunc(u32 btf_id); static bool is_callback_calling_kfunc(u32 btf_id); static bool is_bpf_throw_kfunc(struct bpf_insn *insn); -static bool is_bpf_wq_set_callback_impl_kfunc(u32 btf_id); +static bool is_bpf_wq_set_callback_kfunc(u32 btf_id); static bool is_task_work_add_kfunc(u32 func_id); static bool is_sync_callback_calling_function(enum bpf_func_id func_id) @@ -562,7 +562,7 @@ static bool is_async_cb_sleepable(struct bpf_verifier_env *env, struct bpf_insn /* bpf_wq and bpf_task_work callbacks are always sleepable. */ if (bpf_pseudo_kfunc_call(insn) && insn->off == 0 && - (is_bpf_wq_set_callback_impl_kfunc(insn->imm) || is_task_work_add_kfunc(insn->imm))) + (is_bpf_wq_set_callback_kfunc(insn->imm) || is_task_work_add_kfunc(insn->imm))) return true; verifier_bug(env, "unhandled async callback in is_async_cb_sleepable"); @@ -12470,6 +12470,7 @@ enum special_kfunc_type { KF_bpf_arena_alloc_pages, KF_bpf_arena_free_pages, KF_bpf_arena_reserve_pages, + KF_bpf_wq_set_callback, }; BTF_ID_LIST(special_kfunc_list) @@ -12547,6 +12548,7 @@ BTF_ID(func, bpf_task_work_schedule_resume_impl) BTF_ID(func, bpf_arena_alloc_pages) BTF_ID(func, bpf_arena_free_pages) BTF_ID(func, bpf_arena_reserve_pages) +BTF_ID(func, bpf_wq_set_callback) static bool is_task_work_add_kfunc(u32 func_id) { @@ -13002,7 +13004,7 @@ static bool is_sync_callback_calling_kfunc(u32 btf_id) static bool is_async_callback_calling_kfunc(u32 btf_id) { - return btf_id == special_kfunc_list[KF_bpf_wq_set_callback_impl] || + return is_bpf_wq_set_callback_kfunc(btf_id) || is_task_work_add_kfunc(btf_id); } @@ -13012,9 +13014,10 @@ static bool is_bpf_throw_kfunc(struct bpf_insn *insn) insn->imm == special_kfunc_list[KF_bpf_throw]; } -static bool is_bpf_wq_set_callback_impl_kfunc(u32 btf_id) +static bool is_bpf_wq_set_callback_kfunc(u32 btf_id) { - return btf_id == special_kfunc_list[KF_bpf_wq_set_callback_impl]; + return btf_id == special_kfunc_list[KF_bpf_wq_set_callback_impl] || + btf_id == special_kfunc_list[KF_bpf_wq_set_callback]; } static bool is_callback_calling_kfunc(u32 btf_id) @@ -14093,7 +14096,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, meta.r0_rdonly = false; } - if (is_bpf_wq_set_callback_impl_kfunc(meta.func_id)) { + if (is_bpf_wq_set_callback_kfunc(meta.func_id)) { err = push_callback_call(env, insn, insn_idx, meta.subprogno, set_timer_callback_state); if (err) { diff --git a/tools/testing/selftests/bpf/bpf_experimental.h b/tools/testing/selftests/bpf/bpf_experimental.h index 2cd9165c7348..68a49b1f77ae 100644 --- a/tools/testing/selftests/bpf/bpf_experimental.h +++ b/tools/testing/selftests/bpf/bpf_experimental.h @@ -580,11 +580,6 @@ extern void bpf_iter_css_destroy(struct bpf_iter_css *it) __weak __ksym; extern int bpf_wq_init(struct bpf_wq *wq, void *p__map, unsigned int flags) __weak __ksym; extern int bpf_wq_start(struct bpf_wq *wq, unsigned int flags) __weak __ksym; -extern int bpf_wq_set_callback_impl(struct bpf_wq *wq, - int (callback_fn)(void *map, int *key, void *value), - unsigned int flags__k, void *aux__ign) __ksym; -#define bpf_wq_set_callback(timer, cb, flags) \ - bpf_wq_set_callback_impl(timer, cb, flags, NULL) struct bpf_iter_kmem_cache; extern int bpf_iter_kmem_cache_new(struct bpf_iter_kmem_cache *it) __weak __ksym; diff --git a/tools/testing/selftests/bpf/progs/wq.c b/tools/testing/selftests/bpf/progs/wq.c index 25be2cd9d42c..f265242b954d 100644 --- a/tools/testing/selftests/bpf/progs/wq.c +++ b/tools/testing/selftests/bpf/progs/wq.c @@ -107,7 +107,7 @@ static int test_hmap_elem_callback(void *map, int *key, if (bpf_wq_init(wq, map, 0) != 0) return -3; - if (bpf_wq_set_callback(wq, callback_fn, 0)) + if (bpf_wq_set_callback_impl(wq, callback_fn, 0, NULL)) return -4; if (bpf_wq_start(wq, 0)) diff --git a/tools/testing/selftests/bpf/progs/wq_failures.c b/tools/testing/selftests/bpf/progs/wq_failures.c index d06f6d40594a..3767f5595bbc 100644 --- a/tools/testing/selftests/bpf/progs/wq_failures.c +++ b/tools/testing/selftests/bpf/progs/wq_failures.c @@ -97,7 +97,7 @@ __failure /* check that the first argument of bpf_wq_set_callback() * is a correct bpf_wq pointer. */ -__msg(": (85) call bpf_wq_set_callback_impl#") /* anchor message */ +__msg(": (85) call bpf_wq_set_callback#") /* anchor message */ __msg("arg#0 doesn't point to a map value") long test_wrong_wq_pointer(void *ctx) { @@ -123,7 +123,7 @@ __failure /* check that the first argument of bpf_wq_set_callback() * is a correct bpf_wq pointer. */ -__msg(": (85) call bpf_wq_set_callback_impl#") /* anchor message */ +__msg(": (85) call bpf_wq_set_callback#") /* anchor message */ __msg("off 1 doesn't point to 'struct bpf_wq' that is at 0") long test_wrong_wq_pointer_offset(void *ctx) { -- 2.52.0