From e3b8baf0ca2a69f88846b5446234e5647ecd17eb Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Wed, 21 Sep 2016 11:44:07 +0100 Subject: [PATCH] nfp: bpf: add offload of TC direct action mode Add offload of TC in direct action mode. We just need to provide appropriate checks in the verifier and a new outro block to translate the exit codes to what data path expects Signed-off-by: Jakub Kicinski Signed-off-by: David S. Miller --- drivers/net/ethernet/netronome/nfp/nfp_bpf.h | 1 + drivers/net/ethernet/netronome/nfp/nfp_bpf_jit.c | 66 ++++++++++++++++++++++ .../net/ethernet/netronome/nfp/nfp_bpf_verifier.c | 11 +++- .../net/ethernet/netronome/nfp/nfp_net_offload.c | 6 +- 4 files changed, 82 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/netronome/nfp/nfp_bpf.h b/drivers/net/ethernet/netronome/nfp/nfp_bpf.h index adbe023..fc220cd 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_bpf.h +++ b/drivers/net/ethernet/netronome/nfp/nfp_bpf.h @@ -61,6 +61,7 @@ enum static_regs { enum nfp_bpf_action_type { NN_ACT_TC_DROP, NN_ACT_TC_REDIR, + NN_ACT_DIRECT, }; /* Software register representation, hardware encoding in asm.h */ diff --git a/drivers/net/ethernet/netronome/nfp/nfp_bpf_jit.c b/drivers/net/ethernet/netronome/nfp/nfp_bpf_jit.c index 434bef9..3de819a 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_bpf_jit.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_bpf_jit.c @@ -321,6 +321,16 @@ __emit_br(struct nfp_prog *nfp_prog, enum br_mask mask, enum br_ev_pip ev_pip, nfp_prog_push(nfp_prog, insn); } +static void emit_br_def(struct nfp_prog *nfp_prog, u16 addr, u8 defer) +{ + if (defer > 2) { + pr_err("BUG: branch defer out of bounds %d\n", defer); + nfp_prog->error = -EFAULT; + return; + } + __emit_br(nfp_prog, BR_UNC, BR_EV_PIP_UNCOND, BR_CSS_NONE, addr, defer); +} + static void emit_br(struct nfp_prog *nfp_prog, enum br_mask mask, u16 addr, u8 defer) { @@ -1465,9 +1475,65 @@ static void nfp_outro_tc_legacy(struct nfp_prog *nfp_prog) SHF_SC_L_SHF, 16); } +static void nfp_outro_tc_da(struct nfp_prog *nfp_prog) +{ + /* TC direct-action mode: + * 0,1 ok NOT SUPPORTED[1] + * 2 drop 0x22 -> drop, count as stat1 + * 4,5 nuke 0x02 -> drop + * 7 redir 0x44 -> redir, count as stat2 + * * unspec 0x11 -> pass, count as stat0 + * + * [1] We can't support OK and RECLASSIFY because we can't tell TC + * the exact decision made. We are forced to support UNSPEC + * to handle aborts so that's the only one we handle for passing + * packets up the stack. + */ + /* Target for aborts */ + nfp_prog->tgt_abort = nfp_prog_current_offset(nfp_prog); + + emit_br_def(nfp_prog, nfp_prog->tgt_done, 2); + + emit_alu(nfp_prog, reg_a(0), + reg_none(), ALU_OP_NONE, NFP_BPF_ABI_FLAGS); + emit_ld_field(nfp_prog, reg_a(0), 0xc, reg_imm(0x11), SHF_SC_L_SHF, 16); + + /* Target for normal exits */ + nfp_prog->tgt_out = nfp_prog_current_offset(nfp_prog); + + /* if R0 > 7 jump to abort */ + emit_alu(nfp_prog, reg_none(), reg_imm(7), ALU_OP_SUB, reg_b(0)); + emit_br(nfp_prog, BR_BLO, nfp_prog->tgt_abort, 0); + emit_alu(nfp_prog, reg_a(0), + reg_none(), ALU_OP_NONE, NFP_BPF_ABI_FLAGS); + + wrp_immed(nfp_prog, reg_b(2), 0x41221211); + wrp_immed(nfp_prog, reg_b(3), 0x41001211); + + emit_shf(nfp_prog, reg_a(1), + reg_none(), SHF_OP_NONE, reg_b(0), SHF_SC_L_SHF, 2); + + emit_alu(nfp_prog, reg_none(), reg_a(1), ALU_OP_OR, reg_imm(0)); + emit_shf(nfp_prog, reg_a(2), + reg_imm(0xf), SHF_OP_AND, reg_b(2), SHF_SC_R_SHF, 0); + + emit_alu(nfp_prog, reg_none(), reg_a(1), ALU_OP_OR, reg_imm(0)); + emit_shf(nfp_prog, reg_b(2), + reg_imm(0xf), SHF_OP_AND, reg_b(3), SHF_SC_R_SHF, 0); + + emit_br_def(nfp_prog, nfp_prog->tgt_done, 2); + + emit_shf(nfp_prog, reg_b(2), + reg_a(2), SHF_OP_OR, reg_b(2), SHF_SC_L_SHF, 4); + emit_ld_field(nfp_prog, reg_a(0), 0xc, reg_b(2), SHF_SC_L_SHF, 16); +} + static void nfp_outro(struct nfp_prog *nfp_prog) { switch (nfp_prog->act) { + case NN_ACT_DIRECT: + nfp_outro_tc_da(nfp_prog); + break; case NN_ACT_TC_DROP: case NN_ACT_TC_REDIR: nfp_outro_tc_legacy(nfp_prog); diff --git a/drivers/net/ethernet/netronome/nfp/nfp_bpf_verifier.c b/drivers/net/ethernet/netronome/nfp/nfp_bpf_verifier.c index ef6775b..144cae8 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_bpf_verifier.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_bpf_verifier.c @@ -86,7 +86,16 @@ nfp_bpf_check_exit(struct nfp_prog *nfp_prog, return -EINVAL; } - if (reg0->imm != 0 && (reg0->imm & ~0U) != ~0U) { + if (nfp_prog->act != NN_ACT_DIRECT && + reg0->imm != 0 && (reg0->imm & ~0U) != ~0U) { + pr_info("unsupported exit state: %d, imm: %llx\n", + reg0->type, reg0->imm); + return -EINVAL; + } + + if (nfp_prog->act == NN_ACT_DIRECT && reg0->imm <= TC_ACT_REDIRECT && + reg0->imm != TC_ACT_SHOT && reg0->imm != TC_ACT_STOLEN && + reg0->imm != TC_ACT_QUEUED) { pr_info("unsupported exit state: %d, imm: %llx\n", reg0->type, reg0->imm); return -EINVAL; diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_offload.c b/drivers/net/ethernet/netronome/nfp/nfp_net_offload.c index 1ec8e5b..43f42f8 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_net_offload.c +++ b/drivers/net/ethernet/netronome/nfp/nfp_net_offload.c @@ -112,8 +112,12 @@ nfp_net_bpf_get_act(struct nfp_net *nn, struct tc_cls_bpf_offload *cls_bpf) LIST_HEAD(actions); /* TC direct action */ - if (cls_bpf->exts_integrated) + if (cls_bpf->exts_integrated) { + if (tc_no_actions(cls_bpf->exts)) + return NN_ACT_DIRECT; + return -ENOTSUPP; + } /* TC legacy mode */ if (!tc_single_action(cls_bpf->exts)) -- 2.7.4