diff mbox series

[net-next,16/19] netfilter: nft_exthdr: add reduce support

Message ID 20220321123052.70553-17-pablo@netfilter.org (mailing list archive)
State Accepted
Commit e86dbdb9d4619c3fd9b2ccec159ae1ca41e8ac36
Delegated to: Netdev Maintainers
Headers show
Series [net-next,01/19] netfilter: conntrack: revisit gc autotuning | expand

Checks

Context Check Description
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/subject_prefix success Link
netdev/cover_letter success Pull request is its own cover letter
netdev/patch_count warning Series longer than 15 patches
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 6 this patch: 6
netdev/cc_maintainers warning 4 maintainers not CCed: kadlec@netfilter.org coreteam@netfilter.org pabeni@redhat.com fw@strlen.de
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/module_param success Was 0 now: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 6 this patch: 6
netdev/checkpatch warning CHECK: Alignment should match open parenthesis
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Pablo Neira Ayuso March 21, 2022, 12:30 p.m. UTC 
From: Florian Westphal <fw@strlen.de>

Check if we can elide the load. Cancel if the new candidate
isn't identical to previous store.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/netfilter/nft_exthdr.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)
diff mbox series

Patch

diff --git a/net/netfilter/nft_exthdr.c b/net/netfilter/nft_exthdr.c
index d2b9378164bb..22c3e05b52db 100644
--- a/net/netfilter/nft_exthdr.c
+++ b/net/netfilter/nft_exthdr.c
@@ -603,12 +603,40 @@  static int nft_exthdr_dump_strip(struct sk_buff *skb, const struct nft_expr *exp
 	return nft_exthdr_dump_common(skb, priv);
 }
 
+static bool nft_exthdr_reduce(struct nft_regs_track *track,
+			       const struct nft_expr *expr)
+{
+	const struct nft_exthdr *priv = nft_expr_priv(expr);
+	const struct nft_exthdr *exthdr;
+
+	if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
+		nft_reg_track_update(track, expr, priv->dreg, priv->len);
+		return false;
+	}
+
+	exthdr = nft_expr_priv(track->regs[priv->dreg].selector);
+	if (priv->type != exthdr->type ||
+	    priv->op != exthdr->op ||
+	    priv->flags != exthdr->flags ||
+	    priv->offset != exthdr->offset ||
+	    priv->len != exthdr->len) {
+		nft_reg_track_update(track, expr, priv->dreg, priv->len);
+		return false;
+	}
+
+	if (!track->regs[priv->dreg].bitwise)
+		return true;
+
+	return nft_expr_reduce_bitwise(track, expr);
+}
+
 static const struct nft_expr_ops nft_exthdr_ipv6_ops = {
 	.type		= &nft_exthdr_type,
 	.size		= NFT_EXPR_SIZE(sizeof(struct nft_exthdr)),
 	.eval		= nft_exthdr_ipv6_eval,
 	.init		= nft_exthdr_init,
 	.dump		= nft_exthdr_dump,
+	.reduce		= nft_exthdr_reduce,
 };
 
 static const struct nft_expr_ops nft_exthdr_ipv4_ops = {
@@ -617,6 +645,7 @@  static const struct nft_expr_ops nft_exthdr_ipv4_ops = {
 	.eval		= nft_exthdr_ipv4_eval,
 	.init		= nft_exthdr_ipv4_init,
 	.dump		= nft_exthdr_dump,
+	.reduce		= nft_exthdr_reduce,
 };
 
 static const struct nft_expr_ops nft_exthdr_tcp_ops = {
@@ -625,6 +654,7 @@  static const struct nft_expr_ops nft_exthdr_tcp_ops = {
 	.eval		= nft_exthdr_tcp_eval,
 	.init		= nft_exthdr_init,
 	.dump		= nft_exthdr_dump,
+	.reduce		= nft_exthdr_reduce,
 };
 
 static const struct nft_expr_ops nft_exthdr_tcp_set_ops = {
@@ -633,6 +663,7 @@  static const struct nft_expr_ops nft_exthdr_tcp_set_ops = {
 	.eval		= nft_exthdr_tcp_set_eval,
 	.init		= nft_exthdr_tcp_set_init,
 	.dump		= nft_exthdr_dump_set,
+	.reduce		= NFT_REDUCE_READONLY,
 };
 
 static const struct nft_expr_ops nft_exthdr_tcp_strip_ops = {
@@ -641,6 +672,7 @@  static const struct nft_expr_ops nft_exthdr_tcp_strip_ops = {
 	.eval		= nft_exthdr_tcp_strip_eval,
 	.init		= nft_exthdr_tcp_strip_init,
 	.dump		= nft_exthdr_dump_strip,
+	.reduce		= NFT_REDUCE_READONLY,
 };
 
 static const struct nft_expr_ops nft_exthdr_sctp_ops = {
@@ -649,6 +681,7 @@  static const struct nft_expr_ops nft_exthdr_sctp_ops = {
 	.eval		= nft_exthdr_sctp_eval,
 	.init		= nft_exthdr_init,
 	.dump		= nft_exthdr_dump,
+	.reduce		= nft_exthdr_reduce,
 };
 
 static const struct nft_expr_ops *