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-rw-r--r--arch/riscv/net/bpf_jit_comp64.c1353
1 files changed, 1353 insertions, 0 deletions
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
new file mode 100644
index 000000000..8f5d3c57d
--- /dev/null
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -0,0 +1,1353 @@
+// SPDX-License-Identifier: GPL-2.0
+/* BPF JIT compiler for RV64G
+ *
+ * Copyright(c) 2019 Björn Töpel <bjorn.topel@gmail.com>
+ *
+ */
+
+#include <linux/bitfield.h>
+#include <linux/bpf.h>
+#include <linux/filter.h>
+#include "bpf_jit.h"
+
+#define RV_REG_TCC RV_REG_A6
+#define RV_REG_TCC_SAVED RV_REG_S6 /* Store A6 in S6 if program do calls */
+
+static const int regmap[] = {
+ [BPF_REG_0] = RV_REG_A5,
+ [BPF_REG_1] = RV_REG_A0,
+ [BPF_REG_2] = RV_REG_A1,
+ [BPF_REG_3] = RV_REG_A2,
+ [BPF_REG_4] = RV_REG_A3,
+ [BPF_REG_5] = RV_REG_A4,
+ [BPF_REG_6] = RV_REG_S1,
+ [BPF_REG_7] = RV_REG_S2,
+ [BPF_REG_8] = RV_REG_S3,
+ [BPF_REG_9] = RV_REG_S4,
+ [BPF_REG_FP] = RV_REG_S5,
+ [BPF_REG_AX] = RV_REG_T0,
+};
+
+static const int pt_regmap[] = {
+ [RV_REG_A0] = offsetof(struct pt_regs, a0),
+ [RV_REG_A1] = offsetof(struct pt_regs, a1),
+ [RV_REG_A2] = offsetof(struct pt_regs, a2),
+ [RV_REG_A3] = offsetof(struct pt_regs, a3),
+ [RV_REG_A4] = offsetof(struct pt_regs, a4),
+ [RV_REG_A5] = offsetof(struct pt_regs, a5),
+ [RV_REG_S1] = offsetof(struct pt_regs, s1),
+ [RV_REG_S2] = offsetof(struct pt_regs, s2),
+ [RV_REG_S3] = offsetof(struct pt_regs, s3),
+ [RV_REG_S4] = offsetof(struct pt_regs, s4),
+ [RV_REG_S5] = offsetof(struct pt_regs, s5),
+ [RV_REG_T0] = offsetof(struct pt_regs, t0),
+};
+
+enum {
+ RV_CTX_F_SEEN_TAIL_CALL = 0,
+ RV_CTX_F_SEEN_CALL = RV_REG_RA,
+ RV_CTX_F_SEEN_S1 = RV_REG_S1,
+ RV_CTX_F_SEEN_S2 = RV_REG_S2,
+ RV_CTX_F_SEEN_S3 = RV_REG_S3,
+ RV_CTX_F_SEEN_S4 = RV_REG_S4,
+ RV_CTX_F_SEEN_S5 = RV_REG_S5,
+ RV_CTX_F_SEEN_S6 = RV_REG_S6,
+};
+
+static u8 bpf_to_rv_reg(int bpf_reg, struct rv_jit_context *ctx)
+{
+ u8 reg = regmap[bpf_reg];
+
+ switch (reg) {
+ case RV_CTX_F_SEEN_S1:
+ case RV_CTX_F_SEEN_S2:
+ case RV_CTX_F_SEEN_S3:
+ case RV_CTX_F_SEEN_S4:
+ case RV_CTX_F_SEEN_S5:
+ case RV_CTX_F_SEEN_S6:
+ __set_bit(reg, &ctx->flags);
+ }
+ return reg;
+};
+
+static bool seen_reg(int reg, struct rv_jit_context *ctx)
+{
+ switch (reg) {
+ case RV_CTX_F_SEEN_CALL:
+ case RV_CTX_F_SEEN_S1:
+ case RV_CTX_F_SEEN_S2:
+ case RV_CTX_F_SEEN_S3:
+ case RV_CTX_F_SEEN_S4:
+ case RV_CTX_F_SEEN_S5:
+ case RV_CTX_F_SEEN_S6:
+ return test_bit(reg, &ctx->flags);
+ }
+ return false;
+}
+
+static void mark_fp(struct rv_jit_context *ctx)
+{
+ __set_bit(RV_CTX_F_SEEN_S5, &ctx->flags);
+}
+
+static void mark_call(struct rv_jit_context *ctx)
+{
+ __set_bit(RV_CTX_F_SEEN_CALL, &ctx->flags);
+}
+
+static bool seen_call(struct rv_jit_context *ctx)
+{
+ return test_bit(RV_CTX_F_SEEN_CALL, &ctx->flags);
+}
+
+static void mark_tail_call(struct rv_jit_context *ctx)
+{
+ __set_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags);
+}
+
+static bool seen_tail_call(struct rv_jit_context *ctx)
+{
+ return test_bit(RV_CTX_F_SEEN_TAIL_CALL, &ctx->flags);
+}
+
+static u8 rv_tail_call_reg(struct rv_jit_context *ctx)
+{
+ mark_tail_call(ctx);
+
+ if (seen_call(ctx)) {
+ __set_bit(RV_CTX_F_SEEN_S6, &ctx->flags);
+ return RV_REG_S6;
+ }
+ return RV_REG_A6;
+}
+
+static bool is_32b_int(s64 val)
+{
+ return -(1L << 31) <= val && val < (1L << 31);
+}
+
+static bool in_auipc_jalr_range(s64 val)
+{
+ /*
+ * auipc+jalr can reach any signed PC-relative offset in the range
+ * [-2^31 - 2^11, 2^31 - 2^11).
+ */
+ return (-(1L << 31) - (1L << 11)) <= val &&
+ val < ((1L << 31) - (1L << 11));
+}
+
+/* Emit fixed-length instructions for address */
+static int emit_addr(u8 rd, u64 addr, bool extra_pass, struct rv_jit_context *ctx)
+{
+ u64 ip = (u64)(ctx->insns + ctx->ninsns);
+ s64 off = addr - ip;
+ s64 upper = (off + (1 << 11)) >> 12;
+ s64 lower = off & 0xfff;
+
+ if (extra_pass && !in_auipc_jalr_range(off)) {
+ pr_err("bpf-jit: target offset 0x%llx is out of range\n", off);
+ return -ERANGE;
+ }
+
+ emit(rv_auipc(rd, upper), ctx);
+ emit(rv_addi(rd, rd, lower), ctx);
+ return 0;
+}
+
+/* Emit variable-length instructions for 32-bit and 64-bit imm */
+static void emit_imm(u8 rd, s64 val, struct rv_jit_context *ctx)
+{
+ /* Note that the immediate from the add is sign-extended,
+ * which means that we need to compensate this by adding 2^12,
+ * when the 12th bit is set. A simpler way of doing this, and
+ * getting rid of the check, is to just add 2**11 before the
+ * shift. The "Loading a 32-Bit constant" example from the
+ * "Computer Organization and Design, RISC-V edition" book by
+ * Patterson/Hennessy highlights this fact.
+ *
+ * This also means that we need to process LSB to MSB.
+ */
+ s64 upper = (val + (1 << 11)) >> 12;
+ /* Sign-extend lower 12 bits to 64 bits since immediates for li, addiw,
+ * and addi are signed and RVC checks will perform signed comparisons.
+ */
+ s64 lower = ((val & 0xfff) << 52) >> 52;
+ int shift;
+
+ if (is_32b_int(val)) {
+ if (upper)
+ emit_lui(rd, upper, ctx);
+
+ if (!upper) {
+ emit_li(rd, lower, ctx);
+ return;
+ }
+
+ emit_addiw(rd, rd, lower, ctx);
+ return;
+ }
+
+ shift = __ffs(upper);
+ upper >>= shift;
+ shift += 12;
+
+ emit_imm(rd, upper, ctx);
+
+ emit_slli(rd, rd, shift, ctx);
+ if (lower)
+ emit_addi(rd, rd, lower, ctx);
+}
+
+static void __build_epilogue(bool is_tail_call, struct rv_jit_context *ctx)
+{
+ int stack_adjust = ctx->stack_size, store_offset = stack_adjust - 8;
+
+ if (seen_reg(RV_REG_RA, ctx)) {
+ emit_ld(RV_REG_RA, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ emit_ld(RV_REG_FP, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ if (seen_reg(RV_REG_S1, ctx)) {
+ emit_ld(RV_REG_S1, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S2, ctx)) {
+ emit_ld(RV_REG_S2, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S3, ctx)) {
+ emit_ld(RV_REG_S3, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S4, ctx)) {
+ emit_ld(RV_REG_S4, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S5, ctx)) {
+ emit_ld(RV_REG_S5, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S6, ctx)) {
+ emit_ld(RV_REG_S6, store_offset, RV_REG_SP, ctx);
+ store_offset -= 8;
+ }
+
+ emit_addi(RV_REG_SP, RV_REG_SP, stack_adjust, ctx);
+ /* Set return value. */
+ if (!is_tail_call)
+ emit_addiw(RV_REG_A0, RV_REG_A5, 0, ctx);
+ emit_jalr(RV_REG_ZERO, is_tail_call ? RV_REG_T3 : RV_REG_RA,
+ is_tail_call ? 4 : 0, /* skip TCC init */
+ ctx);
+}
+
+static void emit_bcc(u8 cond, u8 rd, u8 rs, int rvoff,
+ struct rv_jit_context *ctx)
+{
+ switch (cond) {
+ case BPF_JEQ:
+ emit(rv_beq(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JGT:
+ emit(rv_bltu(rs, rd, rvoff >> 1), ctx);
+ return;
+ case BPF_JLT:
+ emit(rv_bltu(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JGE:
+ emit(rv_bgeu(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JLE:
+ emit(rv_bgeu(rs, rd, rvoff >> 1), ctx);
+ return;
+ case BPF_JNE:
+ emit(rv_bne(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JSGT:
+ emit(rv_blt(rs, rd, rvoff >> 1), ctx);
+ return;
+ case BPF_JSLT:
+ emit(rv_blt(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JSGE:
+ emit(rv_bge(rd, rs, rvoff >> 1), ctx);
+ return;
+ case BPF_JSLE:
+ emit(rv_bge(rs, rd, rvoff >> 1), ctx);
+ }
+}
+
+static void emit_branch(u8 cond, u8 rd, u8 rs, int rvoff,
+ struct rv_jit_context *ctx)
+{
+ s64 upper, lower;
+
+ if (is_13b_int(rvoff)) {
+ emit_bcc(cond, rd, rs, rvoff, ctx);
+ return;
+ }
+
+ /* Adjust for jal */
+ rvoff -= 4;
+
+ /* Transform, e.g.:
+ * bne rd,rs,foo
+ * to
+ * beq rd,rs,<.L1>
+ * (auipc foo)
+ * jal(r) foo
+ * .L1
+ */
+ cond = invert_bpf_cond(cond);
+ if (is_21b_int(rvoff)) {
+ emit_bcc(cond, rd, rs, 8, ctx);
+ emit(rv_jal(RV_REG_ZERO, rvoff >> 1), ctx);
+ return;
+ }
+
+ /* 32b No need for an additional rvoff adjustment, since we
+ * get that from the auipc at PC', where PC = PC' + 4.
+ */
+ upper = (rvoff + (1 << 11)) >> 12;
+ lower = rvoff & 0xfff;
+
+ emit_bcc(cond, rd, rs, 12, ctx);
+ emit(rv_auipc(RV_REG_T1, upper), ctx);
+ emit(rv_jalr(RV_REG_ZERO, RV_REG_T1, lower), ctx);
+}
+
+static void emit_zext_32(u8 reg, struct rv_jit_context *ctx)
+{
+ emit_slli(reg, reg, 32, ctx);
+ emit_srli(reg, reg, 32, ctx);
+}
+
+static int emit_bpf_tail_call(int insn, struct rv_jit_context *ctx)
+{
+ int tc_ninsn, off, start_insn = ctx->ninsns;
+ u8 tcc = rv_tail_call_reg(ctx);
+
+ /* a0: &ctx
+ * a1: &array
+ * a2: index
+ *
+ * if (index >= array->map.max_entries)
+ * goto out;
+ */
+ tc_ninsn = insn ? ctx->offset[insn] - ctx->offset[insn - 1] :
+ ctx->offset[0];
+ emit_zext_32(RV_REG_A2, ctx);
+
+ off = offsetof(struct bpf_array, map.max_entries);
+ if (is_12b_check(off, insn))
+ return -1;
+ emit(rv_lwu(RV_REG_T1, off, RV_REG_A1), ctx);
+ off = ninsns_rvoff(tc_ninsn - (ctx->ninsns - start_insn));
+ emit_branch(BPF_JGE, RV_REG_A2, RV_REG_T1, off, ctx);
+
+ /* if (--TCC < 0)
+ * goto out;
+ */
+ emit_addi(RV_REG_TCC, tcc, -1, ctx);
+ off = ninsns_rvoff(tc_ninsn - (ctx->ninsns - start_insn));
+ emit_branch(BPF_JSLT, RV_REG_TCC, RV_REG_ZERO, off, ctx);
+
+ /* prog = array->ptrs[index];
+ * if (!prog)
+ * goto out;
+ */
+ emit_slli(RV_REG_T2, RV_REG_A2, 3, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_A1, ctx);
+ off = offsetof(struct bpf_array, ptrs);
+ if (is_12b_check(off, insn))
+ return -1;
+ emit_ld(RV_REG_T2, off, RV_REG_T2, ctx);
+ off = ninsns_rvoff(tc_ninsn - (ctx->ninsns - start_insn));
+ emit_branch(BPF_JEQ, RV_REG_T2, RV_REG_ZERO, off, ctx);
+
+ /* goto *(prog->bpf_func + 4); */
+ off = offsetof(struct bpf_prog, bpf_func);
+ if (is_12b_check(off, insn))
+ return -1;
+ emit_ld(RV_REG_T3, off, RV_REG_T2, ctx);
+ __build_epilogue(true, ctx);
+ return 0;
+}
+
+static void init_regs(u8 *rd, u8 *rs, const struct bpf_insn *insn,
+ struct rv_jit_context *ctx)
+{
+ u8 code = insn->code;
+
+ switch (code) {
+ case BPF_JMP | BPF_JA:
+ case BPF_JMP | BPF_CALL:
+ case BPF_JMP | BPF_EXIT:
+ case BPF_JMP | BPF_TAIL_CALL:
+ break;
+ default:
+ *rd = bpf_to_rv_reg(insn->dst_reg, ctx);
+ }
+
+ if (code & (BPF_ALU | BPF_X) || code & (BPF_ALU64 | BPF_X) ||
+ code & (BPF_JMP | BPF_X) || code & (BPF_JMP32 | BPF_X) ||
+ code & BPF_LDX || code & BPF_STX)
+ *rs = bpf_to_rv_reg(insn->src_reg, ctx);
+}
+
+static void emit_zext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx)
+{
+ emit_mv(RV_REG_T2, *rd, ctx);
+ emit_zext_32(RV_REG_T2, ctx);
+ emit_mv(RV_REG_T1, *rs, ctx);
+ emit_zext_32(RV_REG_T1, ctx);
+ *rd = RV_REG_T2;
+ *rs = RV_REG_T1;
+}
+
+static void emit_sext_32_rd_rs(u8 *rd, u8 *rs, struct rv_jit_context *ctx)
+{
+ emit_addiw(RV_REG_T2, *rd, 0, ctx);
+ emit_addiw(RV_REG_T1, *rs, 0, ctx);
+ *rd = RV_REG_T2;
+ *rs = RV_REG_T1;
+}
+
+static void emit_zext_32_rd_t1(u8 *rd, struct rv_jit_context *ctx)
+{
+ emit_mv(RV_REG_T2, *rd, ctx);
+ emit_zext_32(RV_REG_T2, ctx);
+ emit_zext_32(RV_REG_T1, ctx);
+ *rd = RV_REG_T2;
+}
+
+static void emit_sext_32_rd(u8 *rd, struct rv_jit_context *ctx)
+{
+ emit_addiw(RV_REG_T2, *rd, 0, ctx);
+ *rd = RV_REG_T2;
+}
+
+static int emit_jump_and_link(u8 rd, s64 rvoff, bool fixed_addr,
+ struct rv_jit_context *ctx)
+{
+ s64 upper, lower;
+
+ if (rvoff && fixed_addr && is_21b_int(rvoff)) {
+ emit(rv_jal(rd, rvoff >> 1), ctx);
+ return 0;
+ } else if (in_auipc_jalr_range(rvoff)) {
+ upper = (rvoff + (1 << 11)) >> 12;
+ lower = rvoff & 0xfff;
+ emit(rv_auipc(RV_REG_T1, upper), ctx);
+ emit(rv_jalr(rd, RV_REG_T1, lower), ctx);
+ return 0;
+ }
+
+ pr_err("bpf-jit: target offset 0x%llx is out of range\n", rvoff);
+ return -ERANGE;
+}
+
+static bool is_signed_bpf_cond(u8 cond)
+{
+ return cond == BPF_JSGT || cond == BPF_JSLT ||
+ cond == BPF_JSGE || cond == BPF_JSLE;
+}
+
+static int emit_call(u64 addr, bool fixed_addr, struct rv_jit_context *ctx)
+{
+ s64 off = 0;
+ u64 ip;
+
+ if (addr && ctx->insns) {
+ ip = (u64)(long)(ctx->insns + ctx->ninsns);
+ off = addr - ip;
+ }
+
+ return emit_jump_and_link(RV_REG_RA, off, fixed_addr, ctx);
+}
+
+static void emit_atomic(u8 rd, u8 rs, s16 off, s32 imm, bool is64,
+ struct rv_jit_context *ctx)
+{
+ u8 r0;
+ int jmp_offset;
+
+ if (off) {
+ if (is_12b_int(off)) {
+ emit_addi(RV_REG_T1, rd, off, ctx);
+ } else {
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
+ }
+ rd = RV_REG_T1;
+ }
+
+ switch (imm) {
+ /* lock *(u32/u64 *)(dst_reg + off16) <op>= src_reg */
+ case BPF_ADD:
+ emit(is64 ? rv_amoadd_d(RV_REG_ZERO, rs, rd, 0, 0) :
+ rv_amoadd_w(RV_REG_ZERO, rs, rd, 0, 0), ctx);
+ break;
+ case BPF_AND:
+ emit(is64 ? rv_amoand_d(RV_REG_ZERO, rs, rd, 0, 0) :
+ rv_amoand_w(RV_REG_ZERO, rs, rd, 0, 0), ctx);
+ break;
+ case BPF_OR:
+ emit(is64 ? rv_amoor_d(RV_REG_ZERO, rs, rd, 0, 0) :
+ rv_amoor_w(RV_REG_ZERO, rs, rd, 0, 0), ctx);
+ break;
+ case BPF_XOR:
+ emit(is64 ? rv_amoxor_d(RV_REG_ZERO, rs, rd, 0, 0) :
+ rv_amoxor_w(RV_REG_ZERO, rs, rd, 0, 0), ctx);
+ break;
+ /* src_reg = atomic_fetch_<op>(dst_reg + off16, src_reg) */
+ case BPF_ADD | BPF_FETCH:
+ emit(is64 ? rv_amoadd_d(rs, rs, rd, 0, 0) :
+ rv_amoadd_w(rs, rs, rd, 0, 0), ctx);
+ if (!is64)
+ emit_zext_32(rs, ctx);
+ break;
+ case BPF_AND | BPF_FETCH:
+ emit(is64 ? rv_amoand_d(rs, rs, rd, 0, 0) :
+ rv_amoand_w(rs, rs, rd, 0, 0), ctx);
+ if (!is64)
+ emit_zext_32(rs, ctx);
+ break;
+ case BPF_OR | BPF_FETCH:
+ emit(is64 ? rv_amoor_d(rs, rs, rd, 0, 0) :
+ rv_amoor_w(rs, rs, rd, 0, 0), ctx);
+ if (!is64)
+ emit_zext_32(rs, ctx);
+ break;
+ case BPF_XOR | BPF_FETCH:
+ emit(is64 ? rv_amoxor_d(rs, rs, rd, 0, 0) :
+ rv_amoxor_w(rs, rs, rd, 0, 0), ctx);
+ if (!is64)
+ emit_zext_32(rs, ctx);
+ break;
+ /* src_reg = atomic_xchg(dst_reg + off16, src_reg); */
+ case BPF_XCHG:
+ emit(is64 ? rv_amoswap_d(rs, rs, rd, 0, 0) :
+ rv_amoswap_w(rs, rs, rd, 0, 0), ctx);
+ if (!is64)
+ emit_zext_32(rs, ctx);
+ break;
+ /* r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg); */
+ case BPF_CMPXCHG:
+ r0 = bpf_to_rv_reg(BPF_REG_0, ctx);
+ emit(is64 ? rv_addi(RV_REG_T2, r0, 0) :
+ rv_addiw(RV_REG_T2, r0, 0), ctx);
+ emit(is64 ? rv_lr_d(r0, 0, rd, 0, 0) :
+ rv_lr_w(r0, 0, rd, 0, 0), ctx);
+ jmp_offset = ninsns_rvoff(8);
+ emit(rv_bne(RV_REG_T2, r0, jmp_offset >> 1), ctx);
+ emit(is64 ? rv_sc_d(RV_REG_T3, rs, rd, 0, 0) :
+ rv_sc_w(RV_REG_T3, rs, rd, 0, 0), ctx);
+ jmp_offset = ninsns_rvoff(-6);
+ emit(rv_bne(RV_REG_T3, 0, jmp_offset >> 1), ctx);
+ emit(rv_fence(0x3, 0x3), ctx);
+ break;
+ }
+}
+
+#define BPF_FIXUP_OFFSET_MASK GENMASK(26, 0)
+#define BPF_FIXUP_REG_MASK GENMASK(31, 27)
+
+bool ex_handler_bpf(const struct exception_table_entry *ex,
+ struct pt_regs *regs)
+{
+ off_t offset = FIELD_GET(BPF_FIXUP_OFFSET_MASK, ex->fixup);
+ int regs_offset = FIELD_GET(BPF_FIXUP_REG_MASK, ex->fixup);
+
+ *(unsigned long *)((void *)regs + pt_regmap[regs_offset]) = 0;
+ regs->epc = (unsigned long)&ex->fixup - offset;
+
+ return true;
+}
+
+/* For accesses to BTF pointers, add an entry to the exception table */
+static int add_exception_handler(const struct bpf_insn *insn,
+ struct rv_jit_context *ctx,
+ int dst_reg, int insn_len)
+{
+ struct exception_table_entry *ex;
+ unsigned long pc;
+ off_t offset;
+
+ if (!ctx->insns || !ctx->prog->aux->extable || BPF_MODE(insn->code) != BPF_PROBE_MEM)
+ return 0;
+
+ if (WARN_ON_ONCE(ctx->nexentries >= ctx->prog->aux->num_exentries))
+ return -EINVAL;
+
+ if (WARN_ON_ONCE(insn_len > ctx->ninsns))
+ return -EINVAL;
+
+ if (WARN_ON_ONCE(!rvc_enabled() && insn_len == 1))
+ return -EINVAL;
+
+ ex = &ctx->prog->aux->extable[ctx->nexentries];
+ pc = (unsigned long)&ctx->insns[ctx->ninsns - insn_len];
+
+ offset = pc - (long)&ex->insn;
+ if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN))
+ return -ERANGE;
+ ex->insn = offset;
+
+ /*
+ * Since the extable follows the program, the fixup offset is always
+ * negative and limited to BPF_JIT_REGION_SIZE. Store a positive value
+ * to keep things simple, and put the destination register in the upper
+ * bits. We don't need to worry about buildtime or runtime sort
+ * modifying the upper bits because the table is already sorted, and
+ * isn't part of the main exception table.
+ */
+ offset = (long)&ex->fixup - (pc + insn_len * sizeof(u16));
+ if (!FIELD_FIT(BPF_FIXUP_OFFSET_MASK, offset))
+ return -ERANGE;
+
+ ex->fixup = FIELD_PREP(BPF_FIXUP_OFFSET_MASK, offset) |
+ FIELD_PREP(BPF_FIXUP_REG_MASK, dst_reg);
+ ex->type = EX_TYPE_BPF;
+
+ ctx->nexentries++;
+ return 0;
+}
+
+int bpf_jit_emit_insn(const struct bpf_insn *insn, struct rv_jit_context *ctx,
+ bool extra_pass)
+{
+ bool is64 = BPF_CLASS(insn->code) == BPF_ALU64 ||
+ BPF_CLASS(insn->code) == BPF_JMP;
+ int s, e, rvoff, ret, i = insn - ctx->prog->insnsi;
+ struct bpf_prog_aux *aux = ctx->prog->aux;
+ u8 rd = -1, rs = -1, code = insn->code;
+ s16 off = insn->off;
+ s32 imm = insn->imm;
+
+ init_regs(&rd, &rs, insn, ctx);
+
+ switch (code) {
+ /* dst = src */
+ case BPF_ALU | BPF_MOV | BPF_X:
+ case BPF_ALU64 | BPF_MOV | BPF_X:
+ if (imm == 1) {
+ /* Special mov32 for zext */
+ emit_zext_32(rd, ctx);
+ break;
+ }
+ emit_mv(rd, rs, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+
+ /* dst = dst OP src */
+ case BPF_ALU | BPF_ADD | BPF_X:
+ case BPF_ALU64 | BPF_ADD | BPF_X:
+ emit_add(rd, rd, rs, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_SUB | BPF_X:
+ case BPF_ALU64 | BPF_SUB | BPF_X:
+ if (is64)
+ emit_sub(rd, rd, rs, ctx);
+ else
+ emit_subw(rd, rd, rs, ctx);
+
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_AND | BPF_X:
+ case BPF_ALU64 | BPF_AND | BPF_X:
+ emit_and(rd, rd, rs, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_OR | BPF_X:
+ case BPF_ALU64 | BPF_OR | BPF_X:
+ emit_or(rd, rd, rs, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_XOR | BPF_X:
+ case BPF_ALU64 | BPF_XOR | BPF_X:
+ emit_xor(rd, rd, rs, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_MUL | BPF_X:
+ case BPF_ALU64 | BPF_MUL | BPF_X:
+ emit(is64 ? rv_mul(rd, rd, rs) : rv_mulw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_DIV | BPF_X:
+ case BPF_ALU64 | BPF_DIV | BPF_X:
+ emit(is64 ? rv_divu(rd, rd, rs) : rv_divuw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_MOD | BPF_X:
+ case BPF_ALU64 | BPF_MOD | BPF_X:
+ emit(is64 ? rv_remu(rd, rd, rs) : rv_remuw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_LSH | BPF_X:
+ case BPF_ALU64 | BPF_LSH | BPF_X:
+ emit(is64 ? rv_sll(rd, rd, rs) : rv_sllw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_RSH | BPF_X:
+ case BPF_ALU64 | BPF_RSH | BPF_X:
+ emit(is64 ? rv_srl(rd, rd, rs) : rv_srlw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_ARSH | BPF_X:
+ case BPF_ALU64 | BPF_ARSH | BPF_X:
+ emit(is64 ? rv_sra(rd, rd, rs) : rv_sraw(rd, rd, rs), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+
+ /* dst = -dst */
+ case BPF_ALU | BPF_NEG:
+ case BPF_ALU64 | BPF_NEG:
+ emit_sub(rd, RV_REG_ZERO, rd, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+
+ /* dst = BSWAP##imm(dst) */
+ case BPF_ALU | BPF_END | BPF_FROM_LE:
+ switch (imm) {
+ case 16:
+ emit_slli(rd, rd, 48, ctx);
+ emit_srli(rd, rd, 48, ctx);
+ break;
+ case 32:
+ if (!aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case 64:
+ /* Do nothing */
+ break;
+ }
+ break;
+
+ case BPF_ALU | BPF_END | BPF_FROM_BE:
+ emit_li(RV_REG_T2, 0, ctx);
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+ if (imm == 16)
+ goto out_be;
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+ if (imm == 32)
+ goto out_be;
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+ emit_slli(RV_REG_T2, RV_REG_T2, 8, ctx);
+ emit_srli(rd, rd, 8, ctx);
+out_be:
+ emit_andi(RV_REG_T1, rd, 0xff, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, RV_REG_T1, ctx);
+
+ emit_mv(rd, RV_REG_T2, ctx);
+ break;
+
+ /* dst = imm */
+ case BPF_ALU | BPF_MOV | BPF_K:
+ case BPF_ALU64 | BPF_MOV | BPF_K:
+ emit_imm(rd, imm, ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+
+ /* dst = dst OP imm */
+ case BPF_ALU | BPF_ADD | BPF_K:
+ case BPF_ALU64 | BPF_ADD | BPF_K:
+ if (is_12b_int(imm)) {
+ emit_addi(rd, rd, imm, ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_add(rd, rd, RV_REG_T1, ctx);
+ }
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_SUB | BPF_K:
+ case BPF_ALU64 | BPF_SUB | BPF_K:
+ if (is_12b_int(-imm)) {
+ emit_addi(rd, rd, -imm, ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_sub(rd, rd, RV_REG_T1, ctx);
+ }
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_AND | BPF_K:
+ case BPF_ALU64 | BPF_AND | BPF_K:
+ if (is_12b_int(imm)) {
+ emit_andi(rd, rd, imm, ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_and(rd, rd, RV_REG_T1, ctx);
+ }
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_OR | BPF_K:
+ case BPF_ALU64 | BPF_OR | BPF_K:
+ if (is_12b_int(imm)) {
+ emit(rv_ori(rd, rd, imm), ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_or(rd, rd, RV_REG_T1, ctx);
+ }
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_XOR | BPF_K:
+ case BPF_ALU64 | BPF_XOR | BPF_K:
+ if (is_12b_int(imm)) {
+ emit(rv_xori(rd, rd, imm), ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_xor(rd, rd, RV_REG_T1, ctx);
+ }
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_MUL | BPF_K:
+ case BPF_ALU64 | BPF_MUL | BPF_K:
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit(is64 ? rv_mul(rd, rd, RV_REG_T1) :
+ rv_mulw(rd, rd, RV_REG_T1), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_DIV | BPF_K:
+ case BPF_ALU64 | BPF_DIV | BPF_K:
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit(is64 ? rv_divu(rd, rd, RV_REG_T1) :
+ rv_divuw(rd, rd, RV_REG_T1), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_MOD | BPF_K:
+ case BPF_ALU64 | BPF_MOD | BPF_K:
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit(is64 ? rv_remu(rd, rd, RV_REG_T1) :
+ rv_remuw(rd, rd, RV_REG_T1), ctx);
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_LSH | BPF_K:
+ case BPF_ALU64 | BPF_LSH | BPF_K:
+ emit_slli(rd, rd, imm, ctx);
+
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_RSH | BPF_K:
+ case BPF_ALU64 | BPF_RSH | BPF_K:
+ if (is64)
+ emit_srli(rd, rd, imm, ctx);
+ else
+ emit(rv_srliw(rd, rd, imm), ctx);
+
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+ case BPF_ALU | BPF_ARSH | BPF_K:
+ case BPF_ALU64 | BPF_ARSH | BPF_K:
+ if (is64)
+ emit_srai(rd, rd, imm, ctx);
+ else
+ emit(rv_sraiw(rd, rd, imm), ctx);
+
+ if (!is64 && !aux->verifier_zext)
+ emit_zext_32(rd, ctx);
+ break;
+
+ /* JUMP off */
+ case BPF_JMP | BPF_JA:
+ rvoff = rv_offset(i, off, ctx);
+ ret = emit_jump_and_link(RV_REG_ZERO, rvoff, true, ctx);
+ if (ret)
+ return ret;
+ break;
+
+ /* IF (dst COND src) JUMP off */
+ case BPF_JMP | BPF_JEQ | BPF_X:
+ case BPF_JMP32 | BPF_JEQ | BPF_X:
+ case BPF_JMP | BPF_JGT | BPF_X:
+ case BPF_JMP32 | BPF_JGT | BPF_X:
+ case BPF_JMP | BPF_JLT | BPF_X:
+ case BPF_JMP32 | BPF_JLT | BPF_X:
+ case BPF_JMP | BPF_JGE | BPF_X:
+ case BPF_JMP32 | BPF_JGE | BPF_X:
+ case BPF_JMP | BPF_JLE | BPF_X:
+ case BPF_JMP32 | BPF_JLE | BPF_X:
+ case BPF_JMP | BPF_JNE | BPF_X:
+ case BPF_JMP32 | BPF_JNE | BPF_X:
+ case BPF_JMP | BPF_JSGT | BPF_X:
+ case BPF_JMP32 | BPF_JSGT | BPF_X:
+ case BPF_JMP | BPF_JSLT | BPF_X:
+ case BPF_JMP32 | BPF_JSLT | BPF_X:
+ case BPF_JMP | BPF_JSGE | BPF_X:
+ case BPF_JMP32 | BPF_JSGE | BPF_X:
+ case BPF_JMP | BPF_JSLE | BPF_X:
+ case BPF_JMP32 | BPF_JSLE | BPF_X:
+ case BPF_JMP | BPF_JSET | BPF_X:
+ case BPF_JMP32 | BPF_JSET | BPF_X:
+ rvoff = rv_offset(i, off, ctx);
+ if (!is64) {
+ s = ctx->ninsns;
+ if (is_signed_bpf_cond(BPF_OP(code)))
+ emit_sext_32_rd_rs(&rd, &rs, ctx);
+ else
+ emit_zext_32_rd_rs(&rd, &rs, ctx);
+ e = ctx->ninsns;
+
+ /* Adjust for extra insns */
+ rvoff -= ninsns_rvoff(e - s);
+ }
+
+ if (BPF_OP(code) == BPF_JSET) {
+ /* Adjust for and */
+ rvoff -= 4;
+ emit_and(RV_REG_T1, rd, rs, ctx);
+ emit_branch(BPF_JNE, RV_REG_T1, RV_REG_ZERO, rvoff,
+ ctx);
+ } else {
+ emit_branch(BPF_OP(code), rd, rs, rvoff, ctx);
+ }
+ break;
+
+ /* IF (dst COND imm) JUMP off */
+ case BPF_JMP | BPF_JEQ | BPF_K:
+ case BPF_JMP32 | BPF_JEQ | BPF_K:
+ case BPF_JMP | BPF_JGT | BPF_K:
+ case BPF_JMP32 | BPF_JGT | BPF_K:
+ case BPF_JMP | BPF_JLT | BPF_K:
+ case BPF_JMP32 | BPF_JLT | BPF_K:
+ case BPF_JMP | BPF_JGE | BPF_K:
+ case BPF_JMP32 | BPF_JGE | BPF_K:
+ case BPF_JMP | BPF_JLE | BPF_K:
+ case BPF_JMP32 | BPF_JLE | BPF_K:
+ case BPF_JMP | BPF_JNE | BPF_K:
+ case BPF_JMP32 | BPF_JNE | BPF_K:
+ case BPF_JMP | BPF_JSGT | BPF_K:
+ case BPF_JMP32 | BPF_JSGT | BPF_K:
+ case BPF_JMP | BPF_JSLT | BPF_K:
+ case BPF_JMP32 | BPF_JSLT | BPF_K:
+ case BPF_JMP | BPF_JSGE | BPF_K:
+ case BPF_JMP32 | BPF_JSGE | BPF_K:
+ case BPF_JMP | BPF_JSLE | BPF_K:
+ case BPF_JMP32 | BPF_JSLE | BPF_K:
+ rvoff = rv_offset(i, off, ctx);
+ s = ctx->ninsns;
+ if (imm) {
+ emit_imm(RV_REG_T1, imm, ctx);
+ rs = RV_REG_T1;
+ } else {
+ /* If imm is 0, simply use zero register. */
+ rs = RV_REG_ZERO;
+ }
+ if (!is64) {
+ if (is_signed_bpf_cond(BPF_OP(code)))
+ emit_sext_32_rd(&rd, ctx);
+ else
+ emit_zext_32_rd_t1(&rd, ctx);
+ }
+ e = ctx->ninsns;
+
+ /* Adjust for extra insns */
+ rvoff -= ninsns_rvoff(e - s);
+ emit_branch(BPF_OP(code), rd, rs, rvoff, ctx);
+ break;
+
+ case BPF_JMP | BPF_JSET | BPF_K:
+ case BPF_JMP32 | BPF_JSET | BPF_K:
+ rvoff = rv_offset(i, off, ctx);
+ s = ctx->ninsns;
+ if (is_12b_int(imm)) {
+ emit_andi(RV_REG_T1, rd, imm, ctx);
+ } else {
+ emit_imm(RV_REG_T1, imm, ctx);
+ emit_and(RV_REG_T1, rd, RV_REG_T1, ctx);
+ }
+ /* For jset32, we should clear the upper 32 bits of t1, but
+ * sign-extension is sufficient here and saves one instruction,
+ * as t1 is used only in comparison against zero.
+ */
+ if (!is64 && imm < 0)
+ emit_addiw(RV_REG_T1, RV_REG_T1, 0, ctx);
+ e = ctx->ninsns;
+ rvoff -= ninsns_rvoff(e - s);
+ emit_branch(BPF_JNE, RV_REG_T1, RV_REG_ZERO, rvoff, ctx);
+ break;
+
+ /* function call */
+ case BPF_JMP | BPF_CALL:
+ {
+ bool fixed_addr;
+ u64 addr;
+
+ mark_call(ctx);
+ ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass,
+ &addr, &fixed_addr);
+ if (ret < 0)
+ return ret;
+
+ ret = emit_call(addr, fixed_addr, ctx);
+ if (ret)
+ return ret;
+
+ if (insn->src_reg != BPF_PSEUDO_CALL)
+ emit_mv(bpf_to_rv_reg(BPF_REG_0, ctx), RV_REG_A0, ctx);
+ break;
+ }
+ /* tail call */
+ case BPF_JMP | BPF_TAIL_CALL:
+ if (emit_bpf_tail_call(i, ctx))
+ return -1;
+ break;
+
+ /* function return */
+ case BPF_JMP | BPF_EXIT:
+ if (i == ctx->prog->len - 1)
+ break;
+
+ rvoff = epilogue_offset(ctx);
+ ret = emit_jump_and_link(RV_REG_ZERO, rvoff, true, ctx);
+ if (ret)
+ return ret;
+ break;
+
+ /* dst = imm64 */
+ case BPF_LD | BPF_IMM | BPF_DW:
+ {
+ struct bpf_insn insn1 = insn[1];
+ u64 imm64;
+
+ imm64 = (u64)insn1.imm << 32 | (u32)imm;
+ if (bpf_pseudo_func(insn)) {
+ /* fixed-length insns for extra jit pass */
+ ret = emit_addr(rd, imm64, extra_pass, ctx);
+ if (ret)
+ return ret;
+ } else {
+ emit_imm(rd, imm64, ctx);
+ }
+
+ return 1;
+ }
+
+ /* LDX: dst = *(size *)(src + off) */
+ case BPF_LDX | BPF_MEM | BPF_B:
+ case BPF_LDX | BPF_MEM | BPF_H:
+ case BPF_LDX | BPF_MEM | BPF_W:
+ case BPF_LDX | BPF_MEM | BPF_DW:
+ case BPF_LDX | BPF_PROBE_MEM | BPF_B:
+ case BPF_LDX | BPF_PROBE_MEM | BPF_H:
+ case BPF_LDX | BPF_PROBE_MEM | BPF_W:
+ case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
+ {
+ int insn_len, insns_start;
+
+ switch (BPF_SIZE(code)) {
+ case BPF_B:
+ if (is_12b_int(off)) {
+ insns_start = ctx->ninsns;
+ emit(rv_lbu(rd, off, rs), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rs, ctx);
+ insns_start = ctx->ninsns;
+ emit(rv_lbu(rd, 0, RV_REG_T1), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ if (insn_is_zext(&insn[1]))
+ return 1;
+ break;
+ case BPF_H:
+ if (is_12b_int(off)) {
+ insns_start = ctx->ninsns;
+ emit(rv_lhu(rd, off, rs), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rs, ctx);
+ insns_start = ctx->ninsns;
+ emit(rv_lhu(rd, 0, RV_REG_T1), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ if (insn_is_zext(&insn[1]))
+ return 1;
+ break;
+ case BPF_W:
+ if (is_12b_int(off)) {
+ insns_start = ctx->ninsns;
+ emit(rv_lwu(rd, off, rs), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rs, ctx);
+ insns_start = ctx->ninsns;
+ emit(rv_lwu(rd, 0, RV_REG_T1), ctx);
+ insn_len = ctx->ninsns - insns_start;
+ if (insn_is_zext(&insn[1]))
+ return 1;
+ break;
+ case BPF_DW:
+ if (is_12b_int(off)) {
+ insns_start = ctx->ninsns;
+ emit_ld(rd, off, rs, ctx);
+ insn_len = ctx->ninsns - insns_start;
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rs, ctx);
+ insns_start = ctx->ninsns;
+ emit_ld(rd, 0, RV_REG_T1, ctx);
+ insn_len = ctx->ninsns - insns_start;
+ break;
+ }
+
+ ret = add_exception_handler(insn, ctx, rd, insn_len);
+ if (ret)
+ return ret;
+ break;
+ }
+ /* speculation barrier */
+ case BPF_ST | BPF_NOSPEC:
+ break;
+
+ /* ST: *(size *)(dst + off) = imm */
+ case BPF_ST | BPF_MEM | BPF_B:
+ emit_imm(RV_REG_T1, imm, ctx);
+ if (is_12b_int(off)) {
+ emit(rv_sb(rd, off, RV_REG_T1), ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T2, off, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
+ emit(rv_sb(RV_REG_T2, 0, RV_REG_T1), ctx);
+ break;
+
+ case BPF_ST | BPF_MEM | BPF_H:
+ emit_imm(RV_REG_T1, imm, ctx);
+ if (is_12b_int(off)) {
+ emit(rv_sh(rd, off, RV_REG_T1), ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T2, off, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
+ emit(rv_sh(RV_REG_T2, 0, RV_REG_T1), ctx);
+ break;
+ case BPF_ST | BPF_MEM | BPF_W:
+ emit_imm(RV_REG_T1, imm, ctx);
+ if (is_12b_int(off)) {
+ emit_sw(rd, off, RV_REG_T1, ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T2, off, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
+ emit_sw(RV_REG_T2, 0, RV_REG_T1, ctx);
+ break;
+ case BPF_ST | BPF_MEM | BPF_DW:
+ emit_imm(RV_REG_T1, imm, ctx);
+ if (is_12b_int(off)) {
+ emit_sd(rd, off, RV_REG_T1, ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T2, off, ctx);
+ emit_add(RV_REG_T2, RV_REG_T2, rd, ctx);
+ emit_sd(RV_REG_T2, 0, RV_REG_T1, ctx);
+ break;
+
+ /* STX: *(size *)(dst + off) = src */
+ case BPF_STX | BPF_MEM | BPF_B:
+ if (is_12b_int(off)) {
+ emit(rv_sb(rd, off, rs), ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
+ emit(rv_sb(RV_REG_T1, 0, rs), ctx);
+ break;
+ case BPF_STX | BPF_MEM | BPF_H:
+ if (is_12b_int(off)) {
+ emit(rv_sh(rd, off, rs), ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
+ emit(rv_sh(RV_REG_T1, 0, rs), ctx);
+ break;
+ case BPF_STX | BPF_MEM | BPF_W:
+ if (is_12b_int(off)) {
+ emit_sw(rd, off, rs, ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
+ emit_sw(RV_REG_T1, 0, rs, ctx);
+ break;
+ case BPF_STX | BPF_MEM | BPF_DW:
+ if (is_12b_int(off)) {
+ emit_sd(rd, off, rs, ctx);
+ break;
+ }
+
+ emit_imm(RV_REG_T1, off, ctx);
+ emit_add(RV_REG_T1, RV_REG_T1, rd, ctx);
+ emit_sd(RV_REG_T1, 0, rs, ctx);
+ break;
+ case BPF_STX | BPF_ATOMIC | BPF_W:
+ case BPF_STX | BPF_ATOMIC | BPF_DW:
+ emit_atomic(rd, rs, off, imm,
+ BPF_SIZE(code) == BPF_DW, ctx);
+ break;
+ default:
+ pr_err("bpf-jit: unknown opcode %02x\n", code);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+void bpf_jit_build_prologue(struct rv_jit_context *ctx)
+{
+ int stack_adjust = 0, store_offset, bpf_stack_adjust;
+
+ bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16);
+ if (bpf_stack_adjust)
+ mark_fp(ctx);
+
+ if (seen_reg(RV_REG_RA, ctx))
+ stack_adjust += 8;
+ stack_adjust += 8; /* RV_REG_FP */
+ if (seen_reg(RV_REG_S1, ctx))
+ stack_adjust += 8;
+ if (seen_reg(RV_REG_S2, ctx))
+ stack_adjust += 8;
+ if (seen_reg(RV_REG_S3, ctx))
+ stack_adjust += 8;
+ if (seen_reg(RV_REG_S4, ctx))
+ stack_adjust += 8;
+ if (seen_reg(RV_REG_S5, ctx))
+ stack_adjust += 8;
+ if (seen_reg(RV_REG_S6, ctx))
+ stack_adjust += 8;
+
+ stack_adjust = round_up(stack_adjust, 16);
+ stack_adjust += bpf_stack_adjust;
+
+ store_offset = stack_adjust - 8;
+
+ /* First instruction is always setting the tail-call-counter
+ * (TCC) register. This instruction is skipped for tail calls.
+ * Force using a 4-byte (non-compressed) instruction.
+ */
+ emit(rv_addi(RV_REG_TCC, RV_REG_ZERO, MAX_TAIL_CALL_CNT), ctx);
+
+ emit_addi(RV_REG_SP, RV_REG_SP, -stack_adjust, ctx);
+
+ if (seen_reg(RV_REG_RA, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_RA, ctx);
+ store_offset -= 8;
+ }
+ emit_sd(RV_REG_SP, store_offset, RV_REG_FP, ctx);
+ store_offset -= 8;
+ if (seen_reg(RV_REG_S1, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S1, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S2, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S2, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S3, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S3, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S4, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S4, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S5, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S5, ctx);
+ store_offset -= 8;
+ }
+ if (seen_reg(RV_REG_S6, ctx)) {
+ emit_sd(RV_REG_SP, store_offset, RV_REG_S6, ctx);
+ store_offset -= 8;
+ }
+
+ emit_addi(RV_REG_FP, RV_REG_SP, stack_adjust, ctx);
+
+ if (bpf_stack_adjust)
+ emit_addi(RV_REG_S5, RV_REG_SP, bpf_stack_adjust, ctx);
+
+ /* Program contains calls and tail calls, so RV_REG_TCC need
+ * to be saved across calls.
+ */
+ if (seen_tail_call(ctx) && seen_call(ctx))
+ emit_mv(RV_REG_TCC_SAVED, RV_REG_TCC, ctx);
+
+ ctx->stack_size = stack_adjust;
+}
+
+void bpf_jit_build_epilogue(struct rv_jit_context *ctx)
+{
+ __build_epilogue(false, ctx);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 11:14:57 +0000