From: Maxim Khmelevskii <max@linux.ibm.com>
To: Alexei Starovoitov <ast@kernel.org>,
Andrii Nakryiko <andrii@kernel.org>,
Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org, Ilya Leoshkevich <iii@linux.ibm.com>,
Heiko Carstens <hca@linux.ibm.com>,
Vasily Gorbik <gor@linux.ibm.com>,
Alexander Gordeev <agordeev@linux.ibm.com>
Subject: [PATCH bpf-next 1/3] s390/bpf: Add emit_ldx and emit_stx functions
Date: Thu, 23 Jul 2026 16:03:49 +0200 [thread overview]
Message-ID: <20260723140648.583055-6-max@linux.ibm.com> (raw)
In-Reply-To: <20260723140648.583055-5-max@linux.ibm.com>
Add new functions for load and store to reuse
them in the load-acquire and store-release logic.
Reviewed-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Maxim Khmelevskii <max@linux.ibm.com>
---
arch/s390/net/bpf_jit_comp.c | 167 +++++++++++++++++------------------
1 file changed, 82 insertions(+), 85 deletions(-)
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 31749c0362ca..e3dc0df551a7 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -830,6 +830,72 @@ static int bpf_jit_probe_post(struct bpf_jit *jit, struct bpf_prog *fp,
return 0;
}
+static int emit_ldx(struct bpf_jit *jit, struct bpf_prog *fp, struct bpf_insn *insn)
+{
+ struct bpf_jit_probe probe;
+
+ bpf_jit_probe_init(&probe);
+ bpf_jit_probe_load_pre(jit, insn, &probe);
+
+ switch (BPF_SIZE(insn->code)) {
+ case BPF_B: /* dst = *(u8 *)(ul) (src + off) */
+ /* llgc %dst,off(%src,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0090, insn->dst_reg, insn->src_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_H: /* dst = *(u16 *)(ul) (src + off) */
+ /* llgh %dst,off(%src,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0091, insn->dst_reg, insn->src_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_W: /* dst = *(u32 *)(ul) (src + off) */
+ /* llgf %dst,off(%src,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0016, insn->dst_reg, insn->src_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_DW: /* dst = *(u64 *)(ul) (src + off) */
+ /* lg %dst,off(%src,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0004, insn->dst_reg, insn->src_reg,
+ probe.arena_reg, insn->off);
+ break;
+ }
+
+ return bpf_jit_probe_post(jit, fp, &probe);
+}
+
+static int emit_stx(struct bpf_jit *jit, struct bpf_prog *fp, struct bpf_insn *insn)
+{
+ struct bpf_jit_probe probe;
+
+ bpf_jit_probe_init(&probe);
+ bpf_jit_probe_store_pre(jit, insn, &probe);
+
+ switch (BPF_SIZE(insn->code)) {
+ case BPF_B: /* *(u8 *)(dst + off) = src_reg */
+ /* stcy %src,off(%dst,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0072, insn->src_reg, insn->dst_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_H: /* (u16 *)(dst + off) = src */
+ /* sthy %src,off(%dst,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0070, insn->src_reg, insn->dst_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_W: /* *(u32 *)(dst + off) = src */
+ /* sty %src,off(%dst,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0050, insn->src_reg, insn->dst_reg,
+ probe.arena_reg, insn->off);
+ break;
+ case BPF_DW: /* (u64 *)(dst + off) = src */
+ /* stg %src,off(%dst,%arena) */
+ EMIT6_DISP_LH(0xe3000000, 0x0024, insn->src_reg, insn->dst_reg,
+ probe.arena_reg, insn->off);
+ break;
+ }
+
+ return bpf_jit_probe_post(jit, fp, &probe);
+}
+
/*
* Sign- or zero-extend the register if necessary
*/
@@ -1477,44 +1543,13 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
*/
case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */
case BPF_STX | BPF_PROBE_MEM32 | BPF_B:
- bpf_jit_probe_store_pre(jit, insn, &probe);
- /* stcy %src,off(%dst,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0072, src_reg, dst_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- jit->seen |= SEEN_MEM;
- break;
case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */
case BPF_STX | BPF_PROBE_MEM32 | BPF_H:
- bpf_jit_probe_store_pre(jit, insn, &probe);
- /* sthy %src,off(%dst,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0070, src_reg, dst_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- jit->seen |= SEEN_MEM;
- break;
case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */
case BPF_STX | BPF_PROBE_MEM32 | BPF_W:
- bpf_jit_probe_store_pre(jit, insn, &probe);
- /* sty %src,off(%dst,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0050, src_reg, dst_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- jit->seen |= SEEN_MEM;
- break;
case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */
case BPF_STX | BPF_PROBE_MEM32 | BPF_DW:
- bpf_jit_probe_store_pre(jit, insn, &probe);
- /* stg %src,off(%dst,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0024, src_reg, dst_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
+ err = emit_stx(jit, fp, insn);
if (err < 0)
return err;
jit->seen |= SEEN_MEM;
@@ -1574,8 +1609,12 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
/*
* BPF_ATOMIC
*/
+ case BPF_STX | BPF_ATOMIC | BPF_B:
+ case BPF_STX | BPF_ATOMIC | BPF_H:
case BPF_STX | BPF_ATOMIC | BPF_DW:
case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_PROBE_ATOMIC | BPF_B:
+ case BPF_STX | BPF_PROBE_ATOMIC | BPF_H:
case BPF_STX | BPF_PROBE_ATOMIC | BPF_DW:
case BPF_STX | BPF_PROBE_ATOMIC | BPF_W:
{
@@ -1687,15 +1726,20 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */
case BPF_LDX | BPF_PROBE_MEM | BPF_B:
case BPF_LDX | BPF_PROBE_MEM32 | BPF_B:
- bpf_jit_probe_load_pre(jit, insn, &probe);
- /* llgc %dst,off(%src,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0090, dst_reg, src_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
+ case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */
+ case BPF_LDX | BPF_PROBE_MEM | BPF_H:
+ case BPF_LDX | BPF_PROBE_MEM32 | BPF_H:
+ case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */
+ case BPF_LDX | BPF_PROBE_MEM | BPF_W:
+ case BPF_LDX | BPF_PROBE_MEM32 | BPF_W:
+ case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */
+ case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
+ case BPF_LDX | BPF_PROBE_MEM32 | BPF_DW:
+ err = emit_ldx(jit, fp, insn);
if (err < 0)
return err;
jit->seen |= SEEN_MEM;
- if (insn_is_zext(&insn[1]))
+ if (BPF_SIZE(insn->code) != BPF_DW && insn_is_zext(&insn[1]))
insn_count = 2;
break;
case BPF_LDX | BPF_MEMSX | BPF_B: /* dst = *(s8 *)(ul) (src + off) */
@@ -1708,20 +1752,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
return err;
jit->seen |= SEEN_MEM;
break;
- case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */
- case BPF_LDX | BPF_PROBE_MEM | BPF_H:
- case BPF_LDX | BPF_PROBE_MEM32 | BPF_H:
- bpf_jit_probe_load_pre(jit, insn, &probe);
- /* llgh %dst,off(%src,%arena) */
- EMIT6_DISP_LH(0xe3000000, 0x0091, dst_reg, src_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- jit->seen |= SEEN_MEM;
- if (insn_is_zext(&insn[1]))
- insn_count = 2;
- break;
case BPF_LDX | BPF_MEMSX | BPF_H: /* dst = *(s16 *)(ul) (src + off) */
case BPF_LDX | BPF_PROBE_MEMSX | BPF_H:
bpf_jit_probe_load_pre(jit, insn, &probe);
@@ -1732,20 +1762,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
return err;
jit->seen |= SEEN_MEM;
break;
- case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */
- case BPF_LDX | BPF_PROBE_MEM | BPF_W:
- case BPF_LDX | BPF_PROBE_MEM32 | BPF_W:
- bpf_jit_probe_load_pre(jit, insn, &probe);
- /* llgf %dst,off(%src) */
- jit->seen |= SEEN_MEM;
- EMIT6_DISP_LH(0xe3000000, 0x0016, dst_reg, src_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- if (insn_is_zext(&insn[1]))
- insn_count = 2;
- break;
case BPF_LDX | BPF_MEMSX | BPF_W: /* dst = *(s32 *)(ul) (src + off) */
case BPF_LDX | BPF_PROBE_MEMSX | BPF_W:
bpf_jit_probe_load_pre(jit, insn, &probe);
@@ -1756,18 +1772,6 @@ static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp,
if (err < 0)
return err;
break;
- case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */
- case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
- case BPF_LDX | BPF_PROBE_MEM32 | BPF_DW:
- bpf_jit_probe_load_pre(jit, insn, &probe);
- /* lg %dst,off(%src,%arena) */
- jit->seen |= SEEN_MEM;
- EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, src_reg,
- probe.arena_reg, off);
- err = bpf_jit_probe_post(jit, fp, &probe);
- if (err < 0)
- return err;
- break;
/*
* BPF_JMP / CALL
*/
@@ -3028,13 +3032,6 @@ bool bpf_jit_supports_insn(struct bpf_insn *insn, bool in_arena)
if (!in_arena)
return true;
switch (insn->code) {
- case BPF_STX | BPF_ATOMIC | BPF_B:
- case BPF_STX | BPF_ATOMIC | BPF_H:
- case BPF_STX | BPF_ATOMIC | BPF_W:
- case BPF_STX | BPF_ATOMIC | BPF_DW:
- if (bpf_atomic_is_load_store(insn))
- return false;
- break;
case BPF_LDX | BPF_MEMSX | BPF_B:
case BPF_LDX | BPF_MEMSX | BPF_H:
case BPF_LDX | BPF_MEMSX | BPF_W:
--
2.55.0
next prev parent reply other threads:[~2026-07-23 14:07 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-07-23 14:03 [PATCH bpf-next 0/3] s390/bpf: Support load-acquire and store-release instructions Maxim Khmelevskii
2026-07-23 14:03 ` Maxim Khmelevskii [this message]
2026-07-23 15:08 ` [PATCH bpf-next 1/3] s390/bpf: Add emit_ldx and emit_stx functions bot+bpf-ci
2026-07-23 14:03 ` [PATCH bpf-next 2/3] s390/bpf: Support load-acquire and store-release instructions Maxim Khmelevskii
2026-07-23 14:03 ` [PATCH bpf-next 3/3] s390/bpf: Enable atomics tests for s390 Maxim Khmelevskii
2026-07-23 14:12 ` sashiko-bot
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20260723140648.583055-6-max@linux.ibm.com \
--to=max@linux.ibm.com \
--cc=agordeev@linux.ibm.com \
--cc=andrii@kernel.org \
--cc=ast@kernel.org \
--cc=bpf@vger.kernel.org \
--cc=daniel@iogearbox.net \
--cc=gor@linux.ibm.com \
--cc=hca@linux.ibm.com \
--cc=iii@linux.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.