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Subject[PATCH 2/3] MIPS,bpf: Implement JLT, JLE, JSLT and JSLE ops in the eBPF JIT.
Date
Signed-off-by: David Daney <david.daney@cavium.com>
---
arch/mips/net/ebpf_jit.c | 101 +++++++++++++++++++++++++++++++++--------------
1 file changed, 72 insertions(+), 29 deletions(-)

diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c
index 721216b..c1e21cb 100644
--- a/arch/mips/net/ebpf_jit.c
+++ b/arch/mips/net/ebpf_jit.c
@@ -990,8 +990,12 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
goto jeq_common;
case BPF_JMP | BPF_JEQ | BPF_X: /* JMP_REG */
case BPF_JMP | BPF_JNE | BPF_X:
+ case BPF_JMP | BPF_JSLT | BPF_X:
+ case BPF_JMP | BPF_JSLE | BPF_X:
case BPF_JMP | BPF_JSGT | BPF_X:
case BPF_JMP | BPF_JSGE | BPF_X:
+ case BPF_JMP | BPF_JLT | BPF_X:
+ case BPF_JMP | BPF_JLE | BPF_X:
case BPF_JMP | BPF_JGT | BPF_X:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JSET | BPF_X:
@@ -1013,28 +1017,34 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
cmp_eq = false;
dst = MIPS_R_AT;
src = MIPS_R_ZERO;
- } else if (BPF_OP(insn->code) == BPF_JSGT) {
+ } else if (BPF_OP(insn->code) == BPF_JSGT || BPF_OP(insn->code) == BPF_JSLE) {
emit_instr(ctx, dsubu, MIPS_R_AT, dst, src);
if ((insn + 1)->code == (BPF_JMP | BPF_EXIT) && insn->off == 1) {
b_off = b_imm(exit_idx, ctx);
if (is_bad_offset(b_off))
return -E2BIG;
- emit_instr(ctx, blez, MIPS_R_AT, b_off);
+ if (BPF_OP(insn->code) == BPF_JSGT)
+ emit_instr(ctx, blez, MIPS_R_AT, b_off);
+ else
+ emit_instr(ctx, bgtz, MIPS_R_AT, b_off);
emit_instr(ctx, nop);
return 2; /* We consumed the exit. */
}
b_off = b_imm(this_idx + insn->off + 1, ctx);
if (is_bad_offset(b_off))
return -E2BIG;
- emit_instr(ctx, bgtz, MIPS_R_AT, b_off);
+ if (BPF_OP(insn->code) == BPF_JSGT)
+ emit_instr(ctx, bgtz, MIPS_R_AT, b_off);
+ else
+ emit_instr(ctx, blez, MIPS_R_AT, b_off);
emit_instr(ctx, nop);
break;
- } else if (BPF_OP(insn->code) == BPF_JSGE) {
+ } else if (BPF_OP(insn->code) == BPF_JSGE || BPF_OP(insn->code) == BPF_JSLT) {
emit_instr(ctx, slt, MIPS_R_AT, dst, src);
- cmp_eq = true;
+ cmp_eq = BPF_OP(insn->code) == BPF_JSGE;
dst = MIPS_R_AT;
src = MIPS_R_ZERO;
- } else if (BPF_OP(insn->code) == BPF_JGT) {
+ } else if (BPF_OP(insn->code) == BPF_JGT || BPF_OP(insn->code) == BPF_JLE) {
/* dst or src could be AT */
emit_instr(ctx, dsubu, MIPS_R_T8, dst, src);
emit_instr(ctx, sltu, MIPS_R_AT, dst, src);
@@ -1042,12 +1052,12 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
emit_instr(ctx, movz, MIPS_R_T9, MIPS_R_SP, MIPS_R_T8);
emit_instr(ctx, movn, MIPS_R_T9, MIPS_R_ZERO, MIPS_R_T8);
emit_instr(ctx, or, MIPS_R_AT, MIPS_R_T9, MIPS_R_AT);
- cmp_eq = true;
+ cmp_eq = BPF_OP(insn->code) == BPF_JGT;
dst = MIPS_R_AT;
src = MIPS_R_ZERO;
- } else if (BPF_OP(insn->code) == BPF_JGE) {
+ } else if (BPF_OP(insn->code) == BPF_JGE || BPF_OP(insn->code) == BPF_JLT) {
emit_instr(ctx, sltu, MIPS_R_AT, dst, src);
- cmp_eq = true;
+ cmp_eq = BPF_OP(insn->code) == BPF_JGE;
dst = MIPS_R_AT;
src = MIPS_R_ZERO;
} else { /* JNE/JEQ case */
@@ -1110,6 +1120,8 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
break;
case BPF_JMP | BPF_JSGT | BPF_K: /* JMP_IMM */
case BPF_JMP | BPF_JSGE | BPF_K: /* JMP_IMM */
+ case BPF_JMP | BPF_JSLT | BPF_K: /* JMP_IMM */
+ case BPF_JMP | BPF_JSLE | BPF_K: /* JMP_IMM */
cmp_eq = (BPF_OP(insn->code) == BPF_JSGE);
dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
if (dst < 0)
@@ -1120,65 +1132,92 @@ static int build_one_insn(const struct bpf_insn *insn, struct jit_ctx *ctx,
b_off = b_imm(exit_idx, ctx);
if (is_bad_offset(b_off))
return -E2BIG;
- if (cmp_eq)
- emit_instr(ctx, bltz, dst, b_off);
- else
+ switch (BPF_OP(insn->code)) {
+ case BPF_JSGT:
emit_instr(ctx, blez, dst, b_off);
+ break;
+ case BPF_JSGE:
+ emit_instr(ctx, bltz, dst, b_off);
+ break;
+ case BPF_JSLT:
+ emit_instr(ctx, bgez, dst, b_off);
+ break;
+ case BPF_JSLE:
+ emit_instr(ctx, bgtz, dst, b_off);
+ break;
+ }
emit_instr(ctx, nop);
return 2; /* We consumed the exit. */
}
b_off = b_imm(this_idx + insn->off + 1, ctx);
if (is_bad_offset(b_off))
return -E2BIG;
- if (cmp_eq)
- emit_instr(ctx, bgez, dst, b_off);
- else
+ switch (BPF_OP(insn->code)) {
+ case BPF_JSGT:
emit_instr(ctx, bgtz, dst, b_off);
+ break;
+ case BPF_JSGE:
+ emit_instr(ctx, bgez, dst, b_off);
+ break;
+ case BPF_JSLT:
+ emit_instr(ctx, bltz, dst, b_off);
+ break;
+ case BPF_JSLE:
+ emit_instr(ctx, blez, dst, b_off);
+ break;
+ }
emit_instr(ctx, nop);
break;
}
/*
* only "LT" compare available, so we must use imm + 1
- * to generate "GT"
+ * to generate "GT" and imm -1 to generate LE
*/
- t64s = insn->imm + (cmp_eq ? 0 : 1);
+ if (BPF_OP(insn->code) == BPF_JSGT)
+ t64s = insn->imm + 1;
+ else if (BPF_OP(insn->code) == BPF_JSLE)
+ t64s = insn->imm + 1;
+ else
+ t64s = insn->imm;
+
+ cmp_eq = BPF_OP(insn->code) == BPF_JSGT || BPF_OP(insn->code) == BPF_JSGE;
if (t64s >= S16_MIN && t64s <= S16_MAX) {
emit_instr(ctx, slti, MIPS_R_AT, dst, (int)t64s);
src = MIPS_R_AT;
dst = MIPS_R_ZERO;
- cmp_eq = true;
goto jeq_common;
}
emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s);
emit_instr(ctx, slt, MIPS_R_AT, dst, MIPS_R_AT);
src = MIPS_R_AT;
dst = MIPS_R_ZERO;
- cmp_eq = true;
goto jeq_common;

case BPF_JMP | BPF_JGT | BPF_K:
case BPF_JMP | BPF_JGE | BPF_K:
+ case BPF_JMP | BPF_JLT | BPF_K:
+ case BPF_JMP | BPF_JLE | BPF_K:
cmp_eq = (BPF_OP(insn->code) == BPF_JGE);
dst = ebpf_to_mips_reg(ctx, insn, dst_reg_fp_ok);
if (dst < 0)
return dst;
/*
* only "LT" compare available, so we must use imm + 1
- * to generate "GT"
+ * to generate "GT" and imm -1 to generate LE
*/
- t64s = (u64)(u32)(insn->imm) + (cmp_eq ? 0 : 1);
- if (t64s >= 0 && t64s <= S16_MAX) {
- emit_instr(ctx, sltiu, MIPS_R_AT, dst, (int)t64s);
- src = MIPS_R_AT;
- dst = MIPS_R_ZERO;
- cmp_eq = true;
- goto jeq_common;
- }
+ if (BPF_OP(insn->code) == BPF_JGT)
+ t64s = (u64)(u32)(insn->imm) + 1;
+ else if (BPF_OP(insn->code) == BPF_JLE)
+ t64s = (u64)(u32)(insn->imm) + 1;
+ else
+ t64s = (u64)(u32)(insn->imm);
+
+ cmp_eq = BPF_OP(insn->code) == BPF_JGT || BPF_OP(insn->code) == BPF_JGE;
+
emit_const_to_reg(ctx, MIPS_R_AT, (u64)t64s);
emit_instr(ctx, sltu, MIPS_R_AT, dst, MIPS_R_AT);
src = MIPS_R_AT;
dst = MIPS_R_ZERO;
- cmp_eq = true;
goto jeq_common;

case BPF_JMP | BPF_JSET | BPF_K: /* JMP_IMM */
@@ -1712,10 +1751,14 @@ static int reg_val_propagate_range(struct jit_ctx *ctx, u64 initial_rvt,
case BPF_JEQ:
case BPF_JGT:
case BPF_JGE:
+ case BPF_JLT:
+ case BPF_JLE:
case BPF_JSET:
case BPF_JNE:
case BPF_JSGT:
case BPF_JSGE:
+ case BPF_JSLT:
+ case BPF_JSLE:
if (follow_taken) {
rvt[idx] |= RVT_BRANCH_TAKEN;
idx += insn->off;
--
2.9.5
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