From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Borkmann Subject: [PATCH bpf-next 07/12] bpf, sparc64: remove ld_abs/ld_ind Date: Thu, 3 May 2018 03:05:31 +0200 Message-ID: <20180503010536.7917-8-daniel@iogearbox.net> References: <20180503010536.7917-1-daniel@iogearbox.net> Cc: netdev@vger.kernel.org, Daniel Borkmann , "David S . Miller" To: ast@kernel.org Return-path: Received: from www62.your-server.de ([213.133.104.62]:36272 "EHLO www62.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751894AbeECBFz (ORCPT ); Wed, 2 May 2018 21:05:55 -0400 In-Reply-To: <20180503010536.7917-1-daniel@iogearbox.net> Sender: netdev-owner@vger.kernel.org List-ID: Since LD_ABS/LD_IND instructions are now removed from the core and reimplemented through a combination of inlined BPF instructions and a slow-path helper, we can get rid of the complexity from sparc64 JIT. Signed-off-by: Daniel Borkmann Cc: David S. Miller Acked-by: Alexei Starovoitov --- arch/sparc/net/Makefile | 5 +- arch/sparc/net/bpf_jit_64.h | 29 ------- arch/sparc/net/bpf_jit_asm_64.S | 162 --------------------------------------- arch/sparc/net/bpf_jit_comp_64.c | 79 +------------------ 4 files changed, 6 insertions(+), 269 deletions(-) delete mode 100644 arch/sparc/net/bpf_jit_asm_64.S diff --git a/arch/sparc/net/Makefile b/arch/sparc/net/Makefile index 76fa8e9..d32aac3 100644 --- a/arch/sparc/net/Makefile +++ b/arch/sparc/net/Makefile @@ -1,4 +1,7 @@ # # Arch-specific network modules # -obj-$(CONFIG_BPF_JIT) += bpf_jit_asm_$(BITS).o bpf_jit_comp_$(BITS).o +obj-$(CONFIG_BPF_JIT) += bpf_jit_comp_$(BITS).o +ifeq ($(BITS),32) +obj-$(CONFIG_BPF_JIT) += bpf_jit_asm_32.o +endif diff --git a/arch/sparc/net/bpf_jit_64.h b/arch/sparc/net/bpf_jit_64.h index 428f7fd..fbc836f 100644 --- a/arch/sparc/net/bpf_jit_64.h +++ b/arch/sparc/net/bpf_jit_64.h @@ -33,35 +33,6 @@ #define I5 0x1d #define FP 0x1e #define I7 0x1f - -#define r_SKB L0 -#define r_HEADLEN L4 -#define r_SKB_DATA L5 -#define r_TMP G1 -#define r_TMP2 G3 - -/* assembly code in arch/sparc/net/bpf_jit_asm_64.S */ -extern u32 bpf_jit_load_word[]; -extern u32 bpf_jit_load_half[]; -extern u32 bpf_jit_load_byte[]; -extern u32 bpf_jit_load_byte_msh[]; -extern u32 bpf_jit_load_word_positive_offset[]; -extern u32 bpf_jit_load_half_positive_offset[]; -extern u32 bpf_jit_load_byte_positive_offset[]; -extern u32 bpf_jit_load_byte_msh_positive_offset[]; -extern u32 bpf_jit_load_word_negative_offset[]; -extern u32 bpf_jit_load_half_negative_offset[]; -extern u32 bpf_jit_load_byte_negative_offset[]; -extern u32 bpf_jit_load_byte_msh_negative_offset[]; - -#else -#define r_RESULT %o0 -#define r_SKB %o0 -#define r_OFF %o1 -#define r_HEADLEN %l4 -#define r_SKB_DATA %l5 -#define r_TMP %g1 -#define r_TMP2 %g3 #endif #endif /* _BPF_JIT_H */ diff --git a/arch/sparc/net/bpf_jit_asm_64.S b/arch/sparc/net/bpf_jit_asm_64.S deleted file mode 100644 index 7177867..0000000 --- a/arch/sparc/net/bpf_jit_asm_64.S +++ /dev/null @@ -1,162 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0 */ -#include - -#include "bpf_jit_64.h" - -#define SAVE_SZ 176 -#define SCRATCH_OFF STACK_BIAS + 128 -#define BE_PTR(label) be,pn %xcc, label -#define SIGN_EXTEND(reg) sra reg, 0, reg - -#define SKF_MAX_NEG_OFF (-0x200000) /* SKF_LL_OFF from filter.h */ - - .text - .globl bpf_jit_load_word -bpf_jit_load_word: - cmp r_OFF, 0 - bl bpf_slow_path_word_neg - nop - .globl bpf_jit_load_word_positive_offset -bpf_jit_load_word_positive_offset: - sub r_HEADLEN, r_OFF, r_TMP - cmp r_TMP, 3 - ble bpf_slow_path_word - add r_SKB_DATA, r_OFF, r_TMP - andcc r_TMP, 3, %g0 - bne load_word_unaligned - nop - retl - ld [r_TMP], r_RESULT -load_word_unaligned: - ldub [r_TMP + 0x0], r_OFF - ldub [r_TMP + 0x1], r_TMP2 - sll r_OFF, 8, r_OFF - or r_OFF, r_TMP2, r_OFF - ldub [r_TMP + 0x2], r_TMP2 - sll r_OFF, 8, r_OFF - or r_OFF, r_TMP2, r_OFF - ldub [r_TMP + 0x3], r_TMP2 - sll r_OFF, 8, r_OFF - retl - or r_OFF, r_TMP2, r_RESULT - - .globl bpf_jit_load_half -bpf_jit_load_half: - cmp r_OFF, 0 - bl bpf_slow_path_half_neg - nop - .globl bpf_jit_load_half_positive_offset -bpf_jit_load_half_positive_offset: - sub r_HEADLEN, r_OFF, r_TMP - cmp r_TMP, 1 - ble bpf_slow_path_half - add r_SKB_DATA, r_OFF, r_TMP - andcc r_TMP, 1, %g0 - bne load_half_unaligned - nop - retl - lduh [r_TMP], r_RESULT -load_half_unaligned: - ldub [r_TMP + 0x0], r_OFF - ldub [r_TMP + 0x1], r_TMP2 - sll r_OFF, 8, r_OFF - retl - or r_OFF, r_TMP2, r_RESULT - - .globl bpf_jit_load_byte -bpf_jit_load_byte: - cmp r_OFF, 0 - bl bpf_slow_path_byte_neg - nop - .globl bpf_jit_load_byte_positive_offset -bpf_jit_load_byte_positive_offset: - cmp r_OFF, r_HEADLEN - bge bpf_slow_path_byte - nop - retl - ldub [r_SKB_DATA + r_OFF], r_RESULT - -#define bpf_slow_path_common(LEN) \ - save %sp, -SAVE_SZ, %sp; \ - mov %i0, %o0; \ - mov %i1, %o1; \ - add %fp, SCRATCH_OFF, %o2; \ - call skb_copy_bits; \ - mov (LEN), %o3; \ - cmp %o0, 0; \ - restore; - -bpf_slow_path_word: - bpf_slow_path_common(4) - bl bpf_error - ld [%sp + SCRATCH_OFF], r_RESULT - retl - nop -bpf_slow_path_half: - bpf_slow_path_common(2) - bl bpf_error - lduh [%sp + SCRATCH_OFF], r_RESULT - retl - nop -bpf_slow_path_byte: - bpf_slow_path_common(1) - bl bpf_error - ldub [%sp + SCRATCH_OFF], r_RESULT - retl - nop - -#define bpf_negative_common(LEN) \ - save %sp, -SAVE_SZ, %sp; \ - mov %i0, %o0; \ - mov %i1, %o1; \ - SIGN_EXTEND(%o1); \ - call bpf_internal_load_pointer_neg_helper; \ - mov (LEN), %o2; \ - mov %o0, r_TMP; \ - cmp %o0, 0; \ - BE_PTR(bpf_error); \ - restore; - -bpf_slow_path_word_neg: - sethi %hi(SKF_MAX_NEG_OFF), r_TMP - cmp r_OFF, r_TMP - bl bpf_error - nop - .globl bpf_jit_load_word_negative_offset -bpf_jit_load_word_negative_offset: - bpf_negative_common(4) - andcc r_TMP, 3, %g0 - bne load_word_unaligned - nop - retl - ld [r_TMP], r_RESULT - -bpf_slow_path_half_neg: - sethi %hi(SKF_MAX_NEG_OFF), r_TMP - cmp r_OFF, r_TMP - bl bpf_error - nop - .globl bpf_jit_load_half_negative_offset -bpf_jit_load_half_negative_offset: - bpf_negative_common(2) - andcc r_TMP, 1, %g0 - bne load_half_unaligned - nop - retl - lduh [r_TMP], r_RESULT - -bpf_slow_path_byte_neg: - sethi %hi(SKF_MAX_NEG_OFF), r_TMP - cmp r_OFF, r_TMP - bl bpf_error - nop - .globl bpf_jit_load_byte_negative_offset -bpf_jit_load_byte_negative_offset: - bpf_negative_common(1) - retl - ldub [r_TMP], r_RESULT - -bpf_error: - /* Make the JIT program itself return zero. */ - ret - restore %g0, %g0, %o0 diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c index 48a2586..9f5918e 100644 --- a/arch/sparc/net/bpf_jit_comp_64.c +++ b/arch/sparc/net/bpf_jit_comp_64.c @@ -48,10 +48,6 @@ static void bpf_flush_icache(void *start_, void *end_) } } -#define SEEN_DATAREF 1 /* might call external helpers */ -#define SEEN_XREG 2 /* ebx is used */ -#define SEEN_MEM 4 /* use mem[] for temporary storage */ - #define S13(X) ((X) & 0x1fff) #define S5(X) ((X) & 0x1f) #define IMMED 0x00002000 @@ -198,7 +194,6 @@ struct jit_ctx { bool tmp_1_used; bool tmp_2_used; bool tmp_3_used; - bool saw_ld_abs_ind; bool saw_frame_pointer; bool saw_call; bool saw_tail_call; @@ -207,9 +202,7 @@ struct jit_ctx { #define TMP_REG_1 (MAX_BPF_JIT_REG + 0) #define TMP_REG_2 (MAX_BPF_JIT_REG + 1) -#define SKB_HLEN_REG (MAX_BPF_JIT_REG + 2) -#define SKB_DATA_REG (MAX_BPF_JIT_REG + 3) -#define TMP_REG_3 (MAX_BPF_JIT_REG + 4) +#define TMP_REG_3 (MAX_BPF_JIT_REG + 2) /* Map BPF registers to SPARC registers */ static const int bpf2sparc[] = { @@ -238,9 +231,6 @@ static const int bpf2sparc[] = { [TMP_REG_1] = G1, [TMP_REG_2] = G2, [TMP_REG_3] = G3, - - [SKB_HLEN_REG] = L4, - [SKB_DATA_REG] = L5, }; static void emit(const u32 insn, struct jit_ctx *ctx) @@ -800,25 +790,6 @@ static int emit_compare_and_branch(const u8 code, const u8 dst, u8 src, return 0; } -static void load_skb_regs(struct jit_ctx *ctx, u8 r_skb) -{ - const u8 r_headlen = bpf2sparc[SKB_HLEN_REG]; - const u8 r_data = bpf2sparc[SKB_DATA_REG]; - const u8 r_tmp = bpf2sparc[TMP_REG_1]; - unsigned int off; - - off = offsetof(struct sk_buff, len); - emit(LD32I | RS1(r_skb) | S13(off) | RD(r_headlen), ctx); - - off = offsetof(struct sk_buff, data_len); - emit(LD32I | RS1(r_skb) | S13(off) | RD(r_tmp), ctx); - - emit(SUB | RS1(r_headlen) | RS2(r_tmp) | RD(r_headlen), ctx); - - off = offsetof(struct sk_buff, data); - emit(LDPTRI | RS1(r_skb) | S13(off) | RD(r_data), ctx); -} - /* Just skip the save instruction and the ctx register move. */ #define BPF_TAILCALL_PROLOGUE_SKIP 16 #define BPF_TAILCALL_CNT_SP_OFF (STACK_BIAS + 128) @@ -857,9 +828,6 @@ static void build_prologue(struct jit_ctx *ctx) emit_reg_move(I0, O0, ctx); /* If you add anything here, adjust BPF_TAILCALL_PROLOGUE_SKIP above. */ - - if (ctx->saw_ld_abs_ind) - load_skb_regs(ctx, bpf2sparc[BPF_REG_1]); } static void build_epilogue(struct jit_ctx *ctx) @@ -1225,16 +1193,11 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) u8 *func = ((u8 *)__bpf_call_base) + imm; ctx->saw_call = true; - if (ctx->saw_ld_abs_ind && bpf_helper_changes_pkt_data(func)) - emit_reg_move(bpf2sparc[BPF_REG_1], L7, ctx); emit_call((u32 *)func, ctx); emit_nop(ctx); emit_reg_move(O0, bpf2sparc[BPF_REG_0], ctx); - - if (ctx->saw_ld_abs_ind && bpf_helper_changes_pkt_data(func)) - load_skb_regs(ctx, L7); break; } @@ -1412,43 +1375,6 @@ static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) emit_nop(ctx); break; } -#define CHOOSE_LOAD_FUNC(K, func) \ - ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) - - /* R0 = ntohx(*(size *)(((struct sk_buff *)R6)->data + imm)) */ - case BPF_LD | BPF_ABS | BPF_W: - func = CHOOSE_LOAD_FUNC(imm, bpf_jit_load_word); - goto common_load; - case BPF_LD | BPF_ABS | BPF_H: - func = CHOOSE_LOAD_FUNC(imm, bpf_jit_load_half); - goto common_load; - case BPF_LD | BPF_ABS | BPF_B: - func = CHOOSE_LOAD_FUNC(imm, bpf_jit_load_byte); - goto common_load; - /* R0 = ntohx(*(size *)(((struct sk_buff *)R6)->data + src + imm)) */ - case BPF_LD | BPF_IND | BPF_W: - func = bpf_jit_load_word; - goto common_load; - case BPF_LD | BPF_IND | BPF_H: - func = bpf_jit_load_half; - goto common_load; - - case BPF_LD | BPF_IND | BPF_B: - func = bpf_jit_load_byte; - common_load: - ctx->saw_ld_abs_ind = true; - - emit_reg_move(bpf2sparc[BPF_REG_6], O0, ctx); - emit_loadimm(imm, O1, ctx); - - if (BPF_MODE(code) == BPF_IND) - emit_alu(ADD, src, O1, ctx); - - emit_call(func, ctx); - emit_alu_K(SRA, O1, 0, ctx); - - emit_reg_move(O0, bpf2sparc[BPF_REG_0], ctx); - break; default: pr_err_once("unknown opcode %02x\n", code); @@ -1583,12 +1509,11 @@ struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) build_epilogue(&ctx); if (bpf_jit_enable > 1) - pr_info("Pass %d: shrink = %d, seen = [%c%c%c%c%c%c%c]\n", pass, + pr_info("Pass %d: shrink = %d, seen = [%c%c%c%c%c%c]\n", pass, image_size - (ctx.idx * 4), ctx.tmp_1_used ? '1' : ' ', ctx.tmp_2_used ? '2' : ' ', ctx.tmp_3_used ? '3' : ' ', - ctx.saw_ld_abs_ind ? 'L' : ' ', ctx.saw_frame_pointer ? 'F' : ' ', ctx.saw_call ? 'C' : ' ', ctx.saw_tail_call ? 'T' : ' '); -- 2.9.5