[v4,bpf-next,4/9] bpf: Remember BTF of inner maps.

Message ID	20210701192044.78034-5-alexei.starovoitov@gmail.com
State	Superseded
Headers	show Return-Path: <netdev-owner@kernel.org> From: Alexei Starovoitov <alexei.starovoitov@gmail.com> To: davem@davemloft.net Cc: daniel@iogearbox.net, andrii@kernel.org, netdev@vger.kernel.org, bpf@vger.kernel.org, kernel-team@fb.com Subject: [PATCH v4 bpf-next 4/9] bpf: Remember BTF of inner maps. Date: Thu, 1 Jul 2021 12:20:39 -0700 Message-Id: <20210701192044.78034-5-alexei.starovoitov@gmail.com> In-Reply-To: <20210701192044.78034-1-alexei.starovoitov@gmail.com> References: <20210701192044.78034-1-alexei.starovoitov@gmail.com> Precedence: bulk
Series	bpf: Introduce BPF timers. \| expand [v4,bpf-next,0/9] bpf: Introduce BPF timers. [v4,bpf-next,1/9] bpf: Introduce bpf timers. [v4,bpf-next,2/9] bpf: Add map side support for bpf timers. [v4,bpf-next,3/9] bpf: Prevent pointer mismatch in bpf_timer_init. [v4,bpf-next,4/9] bpf: Remember BTF of inner maps. [v4,bpf-next,5/9] bpf: Relax verifier recursion check. [v4,bpf-next,6/9] bpf: Implement verifier support for validation of async callbacks. [v4,bpf-next,7/9] bpf: Teach stack depth check about async callbacks. [v4,bpf-next,8/9] selftests/bpf: Add bpf_timer test. [v4,bpf-next,9/9] selftests/bpf: Add a test with bpf_timer in inner map.

Message ID

20210701192044.78034-5-alexei.starovoitov@gmail.com

State

Superseded

Headers

From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
To: davem@davemloft.net
Cc: daniel@iogearbox.net, andrii@kernel.org, netdev@vger.kernel.org,
	bpf@vger.kernel.org, kernel-team@fb.com
Subject: [PATCH v4 bpf-next 4/9] bpf: Remember BTF of inner maps.
Date: Thu,  1 Jul 2021 12:20:39 -0700
Message-Id: <20210701192044.78034-5-alexei.starovoitov@gmail.com>
In-Reply-To: <20210701192044.78034-1-alexei.starovoitov@gmail.com>
References: <20210701192044.78034-1-alexei.starovoitov@gmail.com>
Precedence: bulk

Series

bpf: Introduce BPF timers. | expand

Commit Message

Alexei Starovoitov July 1, 2021, 7:20 p.m. UTC

From: Alexei Starovoitov <ast@kernel.org>

BTF is required for 'struct bpf_timer' to be recognized inside map value.
The bpf timers are supported inside inner maps.
Remember 'struct btf *' in inner_map_meta to make it available
to the verifier in the sequence:

struct bpf_map *inner_map = bpf_map_lookup_elem(&outer_map, ...);
if (inner_map)
    timer = bpf_map_lookup_elem(&inner_map, ...);

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
---
 kernel/bpf/map_in_map.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/kernel/bpf/map_in_map.c b/kernel/bpf/map_in_map.c
index 890dfe14e731..5cd8f5277279 100644
--- a/kernel/bpf/map_in_map.c
+++ b/kernel/bpf/map_in_map.c
@@ -3,6 +3,7 @@ 
  */
 #include <linux/slab.h>
 #include <linux/bpf.h>
+#include <linux/btf.h>
 
 #include "map_in_map.h"
 
@@ -51,6 +52,10 @@  struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd)
 	inner_map_meta->max_entries = inner_map->max_entries;
 	inner_map_meta->spin_lock_off = inner_map->spin_lock_off;
 	inner_map_meta->timer_off = inner_map->timer_off;
+	if (inner_map->btf) {
+		btf_get(inner_map->btf);
+		inner_map_meta->btf = inner_map->btf;
+	}
 
 	/* Misc members not needed in bpf_map_meta_equal() check. */
 	inner_map_meta->ops = inner_map->ops;
@@ -66,6 +71,7 @@  struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd)
 
 void bpf_map_meta_free(struct bpf_map *map_meta)
 {
+	btf_put(map_meta->btf);
 	kfree(map_meta);
 }

[v4,bpf-next,4/9] bpf: Remember BTF of inner maps.

Commit Message

Patch