From 0d49eaf4db2ad18489ff1cfceba17006c1d17b7e Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Thu, 14 Dec 2017 21:29:18 -0800 Subject: [PATCH] nfp: bpf: add basic support for adjust head call Support bpf_xdp_adjust_head(). We need to check whether the packet offset after adjustment is within datapath's limits. We also check if the frame is at least ETH_HLEN long (similar to the kernel implementation). Signed-off-by: Jakub Kicinski Signed-off-by: Daniel Borkmann --- drivers/net/ethernet/netronome/nfp/bpf/fw.h | 54 ++++++++++++++ drivers/net/ethernet/netronome/nfp/bpf/jit.c | 73 +++++++++++++++++++ drivers/net/ethernet/netronome/nfp/bpf/main.c | 38 ++++++++++ drivers/net/ethernet/netronome/nfp/bpf/main.h | 11 +++ .../net/ethernet/netronome/nfp/bpf/verifier.c | 12 +++ drivers/net/ethernet/netronome/nfp/nfp_asm.h | 2 + 6 files changed, 190 insertions(+) create mode 100644 drivers/net/ethernet/netronome/nfp/bpf/fw.h diff --git a/drivers/net/ethernet/netronome/nfp/bpf/fw.h b/drivers/net/ethernet/netronome/nfp/bpf/fw.h new file mode 100644 index 000000000000..7206aa1522db --- /dev/null +++ b/drivers/net/ethernet/netronome/nfp/bpf/fw.h @@ -0,0 +1,54 @@ +/* + * Copyright (C) 2017 Netronome Systems, Inc. + * + * This software is dual licensed under the GNU General License Version 2, + * June 1991 as shown in the file COPYING in the top-level directory of this + * source tree or the BSD 2-Clause License provided below. You have the + * option to license this software under the complete terms of either license. + * + * The BSD 2-Clause License: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * 1. Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * 2. Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#ifndef NFP_BPF_FW_H +#define NFP_BPF_FW_H 1 + +#include +#include + +enum bpf_cap_tlv_type { + NFP_BPF_CAP_TYPE_ADJUST_HEAD = 2, +}; + +struct nfp_bpf_cap_tlv_adjust_head { + __le32 flags; + __le32 off_min; + __le32 off_max; + __le32 guaranteed_sub; + __le32 guaranteed_add; +}; + +#define NFP_BPF_ADJUST_HEAD_NO_META BIT(0) + +#endif diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c index 7afdc6d8e5ac..4bfcb1f3def8 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c @@ -33,6 +33,7 @@ #define pr_fmt(fmt) "NFP net bpf: " fmt +#include #include #include #include @@ -87,6 +88,18 @@ static unsigned int nfp_prog_current_offset(struct nfp_prog *nfp_prog) return nfp_prog->start_off + nfp_prog->prog_len; } +static bool +nfp_prog_confirm_current_offset(struct nfp_prog *nfp_prog, unsigned int off) +{ + /* If there is a recorded error we may have dropped instructions; + * that doesn't have to be due to translator bug, and the translation + * will fail anyway, so just return OK. + */ + if (nfp_prog->error) + return true; + return !WARN_ON_ONCE(nfp_prog_current_offset(nfp_prog) != off); +} + static unsigned int nfp_prog_offset_to_index(struct nfp_prog *nfp_prog, unsigned int offset) { @@ -1196,6 +1209,64 @@ static void wrp_end32(struct nfp_prog *nfp_prog, swreg reg_in, u8 gpr_out) SHF_SC_R_ROT, 16); } +static int adjust_head(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) +{ + swreg tmp = imm_a(nfp_prog), tmp_len = imm_b(nfp_prog); + struct nfp_bpf_cap_adjust_head *adjust_head; + u32 ret_einval, end; + + adjust_head = &nfp_prog->bpf->adjust_head; + + ret_einval = nfp_prog_current_offset(nfp_prog) + 14; + end = ret_einval + 2; + + /* We need to use a temp because offset is just a part of the pkt ptr */ + emit_alu(nfp_prog, tmp, + reg_a(2 * 2), ALU_OP_ADD_2B, pptr_reg(nfp_prog)); + + /* Validate result will fit within FW datapath constraints */ + emit_alu(nfp_prog, reg_none(), + tmp, ALU_OP_SUB, reg_imm(adjust_head->off_min)); + emit_br(nfp_prog, BR_BLO, ret_einval, 0); + emit_alu(nfp_prog, reg_none(), + reg_imm(adjust_head->off_max), ALU_OP_SUB, tmp); + emit_br(nfp_prog, BR_BLO, ret_einval, 0); + + /* Validate the length is at least ETH_HLEN */ + emit_alu(nfp_prog, tmp_len, + plen_reg(nfp_prog), ALU_OP_SUB, reg_a(2 * 2)); + emit_alu(nfp_prog, reg_none(), + tmp_len, ALU_OP_SUB, reg_imm(ETH_HLEN)); + emit_br(nfp_prog, BR_BMI, ret_einval, 0); + + /* Load the ret code */ + wrp_immed(nfp_prog, reg_both(0), 0); + wrp_immed(nfp_prog, reg_both(1), 0); + + /* Modify the packet metadata */ + emit_ld_field(nfp_prog, pptr_reg(nfp_prog), 0x3, tmp, SHF_SC_NONE, 0); + + /* Skip over the -EINVAL ret code (defer 2) */ + emit_br_def(nfp_prog, end, 2); + + emit_alu(nfp_prog, plen_reg(nfp_prog), + plen_reg(nfp_prog), ALU_OP_SUB, reg_a(2 * 2)); + emit_alu(nfp_prog, pv_len(nfp_prog), + pv_len(nfp_prog), ALU_OP_SUB, reg_a(2 * 2)); + + /* return -EINVAL target */ + if (!nfp_prog_confirm_current_offset(nfp_prog, ret_einval)) + return -EINVAL; + + wrp_immed(nfp_prog, reg_both(0), -22); + wrp_immed(nfp_prog, reg_both(1), ~0); + + if (!nfp_prog_confirm_current_offset(nfp_prog, end)) + return -EINVAL; + + return 0; +} + /* --- Callbacks --- */ static int mov_reg64(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) { @@ -1933,6 +2004,8 @@ static int jne_reg(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) static int call(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) { switch (meta->insn.imm) { + case BPF_FUNC_xdp_adjust_head: + return adjust_head(nfp_prog, meta); default: WARN_ONCE(1, "verifier allowed unsupported function\n"); return -EOPNOTSUPP; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c b/drivers/net/ethernet/netronome/nfp/bpf/main.c index f76bb40c20bc..bd4a1dcc58b3 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/main.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c @@ -39,6 +39,7 @@ #include "../nfp_main.h" #include "../nfp_net.h" #include "../nfp_port.h" +#include "fw.h" #include "main.h" static bool nfp_net_ebpf_capable(struct nfp_net *nn) @@ -156,6 +157,36 @@ static bool nfp_bpf_tc_busy(struct nfp_app *app, struct nfp_net *nn) return nn->dp.ctrl & NFP_NET_CFG_CTRL_BPF; } +static int +nfp_bpf_parse_cap_adjust_head(struct nfp_app_bpf *bpf, void __iomem *value, + u32 length) +{ + struct nfp_bpf_cap_tlv_adjust_head __iomem *cap = value; + struct nfp_cpp *cpp = bpf->app->pf->cpp; + + if (length < sizeof(*cap)) { + nfp_err(cpp, "truncated adjust_head TLV: %d\n", length); + return -EINVAL; + } + + bpf->adjust_head.flags = readl(&cap->flags); + bpf->adjust_head.off_min = readl(&cap->off_min); + bpf->adjust_head.off_max = readl(&cap->off_max); + + if (bpf->adjust_head.off_min > bpf->adjust_head.off_max) { + nfp_err(cpp, "invalid adjust_head TLV: min > max\n"); + return -EINVAL; + } + if (!FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_min) || + !FIELD_FIT(UR_REG_IMM_MAX, bpf->adjust_head.off_max)) { + nfp_warn(cpp, "disabling adjust_head - driver expects min/max to fit in as immediates\n"); + memset(&bpf->adjust_head, 0, sizeof(bpf->adjust_head)); + return 0; + } + + return 0; +} + static int nfp_bpf_parse_capabilities(struct nfp_app *app) { struct nfp_cpp *cpp = app->pf->cpp; @@ -169,16 +200,23 @@ static int nfp_bpf_parse_capabilities(struct nfp_app *app) start = mem; while (mem - start + 8 < nfp_cpp_area_size(area)) { + u8 __iomem *value; u32 type, length; type = readl(mem); length = readl(mem + 4); + value = mem + 8; mem += 8 + length; if (mem - start > nfp_cpp_area_size(area)) goto err_release_free; switch (type) { + case NFP_BPF_CAP_TYPE_ADJUST_HEAD: + if (nfp_bpf_parse_cap_adjust_head(app->priv, value, + length)) + goto err_release_free; + break; default: nfp_dbg(cpp, "unknown BPF capability: %d\n", type); break; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h index a1a3f96353df..00a46258fb6d 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/main.h +++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h @@ -81,9 +81,20 @@ enum pkt_vec { /** * struct nfp_app_bpf - bpf app priv structure * @app: backpointer to the app + * + * @adjust_head: adjust head capability + * @flags: extra flags for adjust head + * @off_min: minimal packet offset within buffer required + * @off_max: maximum packet offset within buffer required */ struct nfp_app_bpf { struct nfp_app *app; + + struct nfp_bpf_cap_adjust_head { + u32 flags; + int off_min; + int off_max; + } adjust_head; }; struct nfp_prog; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c index 3b940b682ac3..0a457d98666c 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c @@ -38,6 +38,7 @@ #include #include +#include "fw.h" #include "main.h" struct nfp_insn_meta * @@ -71,9 +72,20 @@ nfp_bpf_goto_meta(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta, static int nfp_bpf_check_call(struct nfp_prog *nfp_prog, struct nfp_insn_meta *meta) { + struct nfp_app_bpf *bpf = nfp_prog->bpf; u32 func_id = meta->insn.imm; switch (func_id) { + case BPF_FUNC_xdp_adjust_head: + if (!bpf->adjust_head.off_max) { + pr_warn("adjust_head not supported by FW\n"); + return -EOPNOTSUPP; + } + if (!(bpf->adjust_head.flags & NFP_BPF_ADJUST_HEAD_NO_META)) { + pr_warn("adjust_head: FW requires shifting metadata, not supported by the driver\n"); + return -EOPNOTSUPP; + } + break; default: pr_warn("unsupported function id: %d\n", func_id); return -EOPNOTSUPP; diff --git a/drivers/net/ethernet/netronome/nfp/nfp_asm.h b/drivers/net/ethernet/netronome/nfp/nfp_asm.h index 3387e6926eb0..a24daeab1a77 100644 --- a/drivers/net/ethernet/netronome/nfp/nfp_asm.h +++ b/drivers/net/ethernet/netronome/nfp/nfp_asm.h @@ -77,6 +77,7 @@ enum br_mask { BR_BEQ = 0x00, BR_BNE = 0x01, + BR_BMI = 0x02, BR_BHS = 0x04, BR_BLO = 0x05, BR_BGE = 0x08, @@ -175,6 +176,7 @@ enum alu_op { ALU_OP_NONE = 0x00, ALU_OP_ADD = 0x01, ALU_OP_NOT = 0x04, + ALU_OP_ADD_2B = 0x05, ALU_OP_AND = 0x08, ALU_OP_SUB_C = 0x0d, ALU_OP_ADD_C = 0x11, -- 2.20.1