diff mbox series

[RFC,v2,2/7] bpf: Add vnet_hash members to __sk_buff

Message ID 20231015141644.260646-3-akihiko.odaki@daynix.com
State New
Headers show
Series tun: Introduce virtio-net hashing feature | expand

Commit Message

Akihiko Odaki Oct. 15, 2023, 2:16 p.m. UTC 
They will be used only by BPF_PROG_TYPE_VNET_HASH to tell the queues to
deliver packets and the hash values and types reported with virtio-net
headers.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/linux/filter.h         |  7 ++++
 net/core/filter.c              | 77 +++++++++++++++++++++++++++++++++-
 tools/include/uapi/linux/bpf.h |  4 ++
 3 files changed, 86 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/include/linux/filter.h b/include/linux/filter.h
index bf7ad887943c..d10afe92ee45 100644
--- a/include/linux/filter.h
+++ b/include/linux/filter.h
@@ -643,6 +643,13 @@  struct bpf_skb_data_end {
 	void *data_end;
 };
 
+struct bpf_skb_vnet_hash_end {
+	struct qdisc_skb_cb qdisc_cb;
+	u32 hash_value;
+	u16 hash_report;
+	u16 rss_queue;
+};
+
 struct bpf_nh_params {
 	u32 nh_family;
 	union {
diff --git a/net/core/filter.c b/net/core/filter.c
index 867edbc628de..35bc60b71722 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -8435,9 +8435,15 @@  static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type
 	case bpf_ctx_range(struct __sk_buff, data):
 	case bpf_ctx_range(struct __sk_buff, data_meta):
 	case bpf_ctx_range(struct __sk_buff, data_end):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
 		if (size != size_default)
 			return false;
 		break;
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
+		if (size != sizeof(__u16))
+			return false;
+		break;
 	case bpf_ctx_range_ptr(struct __sk_buff, flow_keys):
 		return false;
 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
@@ -8473,7 +8479,7 @@  static bool bpf_skb_is_valid_access(int off, int size, enum bpf_access_type type
 	return true;
 }
 
-static bool sk_filter_is_valid_access(int off, int size,
+static bool vnet_hash_is_valid_access(int off, int size,
 				      enum bpf_access_type type,
 				      const struct bpf_prog *prog,
 				      struct bpf_insn_access_aux *info)
@@ -8493,6 +8499,9 @@  static bool sk_filter_is_valid_access(int off, int size,
 	if (type == BPF_WRITE) {
 		switch (off) {
 		case bpf_ctx_range_till(struct __sk_buff, cb[0], cb[4]):
+		case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+		case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+		case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
 			break;
 		default:
 			return false;
@@ -8502,6 +8511,21 @@  static bool sk_filter_is_valid_access(int off, int size,
 	return bpf_skb_is_valid_access(off, size, type, prog, info);
 }
 
+static bool sk_filter_is_valid_access(int off, int size,
+				      enum bpf_access_type type,
+				      const struct bpf_prog *prog,
+				      struct bpf_insn_access_aux *info)
+{
+	switch (off) {
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
+		return false;
+	}
+
+	return vnet_hash_is_valid_access(off, size, type, prog, info);
+}
+
 static bool cg_skb_is_valid_access(int off, int size,
 				   enum bpf_access_type type,
 				   const struct bpf_prog *prog,
@@ -8511,6 +8535,9 @@  static bool cg_skb_is_valid_access(int off, int size,
 	case bpf_ctx_range(struct __sk_buff, tc_classid):
 	case bpf_ctx_range(struct __sk_buff, data_meta):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
 		return false;
 	case bpf_ctx_range(struct __sk_buff, data):
 	case bpf_ctx_range(struct __sk_buff, data_end):
@@ -8558,6 +8585,9 @@  static bool lwt_is_valid_access(int off, int size,
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
 		return false;
 	}
 
@@ -8799,6 +8829,10 @@  static bool tc_cls_act_is_valid_access(int off, int size,
 	}
 
 	switch (off) {
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
+		return false;
 	case bpf_ctx_range(struct __sk_buff, data):
 		info->reg_type = PTR_TO_PACKET;
 		break;
@@ -9117,6 +9151,9 @@  static bool sk_skb_is_valid_access(int off, int size,
 	case bpf_ctx_range(struct __sk_buff, tstamp):
 	case bpf_ctx_range(struct __sk_buff, wire_len):
 	case bpf_ctx_range(struct __sk_buff, hwtstamp):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_value):
+	case bpf_ctx_range(struct __sk_buff, vnet_hash_report):
+	case bpf_ctx_range(struct __sk_buff, vnet_rss_queue):
 		return false;
 	}
 
@@ -9727,6 +9764,42 @@  static u32 bpf_convert_ctx_access(enum bpf_access_type type,
 						     hwtstamps, 8,
 						     target_size));
 		break;
+
+	case offsetof(struct __sk_buff, vnet_hash_value):
+		BUILD_BUG_ON(sizeof_field(struct bpf_skb_vnet_hash_end, hash_value) != 4);
+
+		off = offsetof(struct sk_buff, cb) +
+		      offsetof(struct bpf_skb_vnet_hash_end, hash_value);
+
+		if (type == BPF_WRITE)
+			*insn++ = BPF_EMIT_STORE(BPF_W, si, off);
+		else
+			*insn++ = BPF_LDX_MEM(BPF_W, si->dst_reg, si->src_reg, off);
+		break;
+
+	case offsetof(struct __sk_buff, vnet_hash_report):
+		BUILD_BUG_ON(sizeof_field(struct bpf_skb_vnet_hash_end, hash_report) != 2);
+
+		off = offsetof(struct sk_buff, cb) +
+		      offsetof(struct bpf_skb_vnet_hash_end, hash_report);
+
+		if (type == BPF_WRITE)
+			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
+		else
+			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, off);
+		break;
+
+	case offsetof(struct __sk_buff, vnet_rss_queue):
+		BUILD_BUG_ON(sizeof_field(struct bpf_skb_vnet_hash_end, rss_queue) != 2);
+
+		off = offsetof(struct sk_buff, cb) +
+		      offsetof(struct bpf_skb_vnet_hash_end, rss_queue);
+
+		if (type == BPF_WRITE)
+			*insn++ = BPF_EMIT_STORE(BPF_H, si, off);
+		else
+			*insn++ = BPF_LDX_MEM(BPF_H, si->dst_reg, si->src_reg, off);
+		break;
 	}
 
 	return insn - insn_buf;
@@ -10969,7 +11042,7 @@  const struct bpf_prog_ops flow_dissector_prog_ops = {
 
 const struct bpf_verifier_ops vnet_hash_verifier_ops = {
 	.get_func_proto		= sk_filter_func_proto,
-	.is_valid_access	= sk_filter_is_valid_access,
+	.is_valid_access	= vnet_hash_is_valid_access,
 	.convert_ctx_access	= bpf_convert_ctx_access,
 	.gen_ld_abs		= bpf_gen_ld_abs,
 };
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 60976fe86247..298634556fab 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -6112,6 +6112,10 @@  struct __sk_buff {
 	__u8  tstamp_type;
 	__u32 :24;		/* Padding, future use. */
 	__u64 hwtstamp;
+
+	__u32 vnet_hash_value;
+	__u16 vnet_hash_report;
+	__u16 vnet_rss_queue;
 };
 
 struct bpf_tunnel_key {