diff options
Diffstat (limited to 'arch/sparc/net/bpf_jit_comp_64.c')
| -rw-r--r-- | arch/sparc/net/bpf_jit_comp_64.c | 1566 |
1 files changed, 1566 insertions, 0 deletions
diff --git a/arch/sparc/net/bpf_jit_comp_64.c b/arch/sparc/net/bpf_jit_comp_64.c new file mode 100644 index 000000000000..21de77419f48 --- /dev/null +++ b/arch/sparc/net/bpf_jit_comp_64.c @@ -0,0 +1,1566 @@ +#include <linux/moduleloader.h> +#include <linux/workqueue.h> +#include <linux/netdevice.h> +#include <linux/filter.h> +#include <linux/bpf.h> +#include <linux/cache.h> +#include <linux/if_vlan.h> + +#include <asm/cacheflush.h> +#include <asm/ptrace.h> + +#include "bpf_jit_64.h" + +int bpf_jit_enable __read_mostly; + +static inline bool is_simm13(unsigned int value) +{ + return value + 0x1000 < 0x2000; +} + +static inline bool is_simm10(unsigned int value) +{ + return value + 0x200 < 0x400; +} + +static inline bool is_simm5(unsigned int value) +{ + return value + 0x10 < 0x20; +} + +static inline bool is_sethi(unsigned int value) +{ + return (value & ~0x3fffff) == 0; +} + +static void bpf_flush_icache(void *start_, void *end_) +{ + /* Cheetah's I-cache is fully coherent. */ + if (tlb_type == spitfire) { + unsigned long start = (unsigned long) start_; + unsigned long end = (unsigned long) end_; + + start &= ~7UL; + end = (end + 7UL) & ~7UL; + while (start < end) { + flushi(start); + start += 32; + } + } +} + +#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 +#define RD(X) ((X) << 25) +#define RS1(X) ((X) << 14) +#define RS2(X) ((X)) +#define OP(X) ((X) << 30) +#define OP2(X) ((X) << 22) +#define OP3(X) ((X) << 19) +#define COND(X) (((X) & 0xf) << 25) +#define CBCOND(X) (((X) & 0x1f) << 25) +#define F1(X) OP(X) +#define F2(X, Y) (OP(X) | OP2(Y)) +#define F3(X, Y) (OP(X) | OP3(Y)) +#define ASI(X) (((X) & 0xff) << 5) + +#define CONDN COND(0x0) +#define CONDE COND(0x1) +#define CONDLE COND(0x2) +#define CONDL COND(0x3) +#define CONDLEU COND(0x4) +#define CONDCS COND(0x5) +#define CONDNEG COND(0x6) +#define CONDVC COND(0x7) +#define CONDA COND(0x8) +#define CONDNE COND(0x9) +#define CONDG COND(0xa) +#define CONDGE COND(0xb) +#define CONDGU COND(0xc) +#define CONDCC COND(0xd) +#define CONDPOS COND(0xe) +#define CONDVS COND(0xf) + +#define CONDGEU CONDCC +#define CONDLU CONDCS + +#define WDISP22(X) (((X) >> 2) & 0x3fffff) +#define WDISP19(X) (((X) >> 2) & 0x7ffff) + +/* The 10-bit branch displacement for CBCOND is split into two fields */ +static u32 WDISP10(u32 off) +{ + u32 ret = ((off >> 2) & 0xff) << 5; + + ret |= ((off >> (2 + 8)) & 0x03) << 19; + + return ret; +} + +#define CBCONDE CBCOND(0x09) +#define CBCONDLE CBCOND(0x0a) +#define CBCONDL CBCOND(0x0b) +#define CBCONDLEU CBCOND(0x0c) +#define CBCONDCS CBCOND(0x0d) +#define CBCONDN CBCOND(0x0e) +#define CBCONDVS CBCOND(0x0f) +#define CBCONDNE CBCOND(0x19) +#define CBCONDG CBCOND(0x1a) +#define CBCONDGE CBCOND(0x1b) +#define CBCONDGU CBCOND(0x1c) +#define CBCONDCC CBCOND(0x1d) +#define CBCONDPOS CBCOND(0x1e) +#define CBCONDVC CBCOND(0x1f) + +#define CBCONDGEU CBCONDCC +#define CBCONDLU CBCONDCS + +#define ANNUL (1 << 29) +#define XCC (1 << 21) + +#define BRANCH (F2(0, 1) | XCC) +#define CBCOND_OP (F2(0, 3) | XCC) + +#define BA (BRANCH | CONDA) +#define BG (BRANCH | CONDG) +#define BGU (BRANCH | CONDGU) +#define BLEU (BRANCH | CONDLEU) +#define BGE (BRANCH | CONDGE) +#define BGEU (BRANCH | CONDGEU) +#define BLU (BRANCH | CONDLU) +#define BE (BRANCH | CONDE) +#define BNE (BRANCH | CONDNE) + +#define SETHI(K, REG) \ + (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff)) +#define OR_LO(K, REG) \ + (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG)) + +#define ADD F3(2, 0x00) +#define AND F3(2, 0x01) +#define ANDCC F3(2, 0x11) +#define OR F3(2, 0x02) +#define XOR F3(2, 0x03) +#define SUB F3(2, 0x04) +#define SUBCC F3(2, 0x14) +#define MUL F3(2, 0x0a) +#define MULX F3(2, 0x09) +#define UDIVX F3(2, 0x0d) +#define DIV F3(2, 0x0e) +#define SLL F3(2, 0x25) +#define SLLX (F3(2, 0x25)|(1<<12)) +#define SRA F3(2, 0x27) +#define SRAX (F3(2, 0x27)|(1<<12)) +#define SRL F3(2, 0x26) +#define SRLX (F3(2, 0x26)|(1<<12)) +#define JMPL F3(2, 0x38) +#define SAVE F3(2, 0x3c) +#define RESTORE F3(2, 0x3d) +#define CALL F1(1) +#define BR F2(0, 0x01) +#define RD_Y F3(2, 0x28) +#define WR_Y F3(2, 0x30) + +#define LD32 F3(3, 0x00) +#define LD8 F3(3, 0x01) +#define LD16 F3(3, 0x02) +#define LD64 F3(3, 0x0b) +#define LD64A F3(3, 0x1b) +#define ST8 F3(3, 0x05) +#define ST16 F3(3, 0x06) +#define ST32 F3(3, 0x04) +#define ST64 F3(3, 0x0e) + +#define CAS F3(3, 0x3c) +#define CASX F3(3, 0x3e) + +#define LDPTR LD64 +#define BASE_STACKFRAME 176 + +#define LD32I (LD32 | IMMED) +#define LD8I (LD8 | IMMED) +#define LD16I (LD16 | IMMED) +#define LD64I (LD64 | IMMED) +#define LDPTRI (LDPTR | IMMED) +#define ST32I (ST32 | IMMED) + +struct jit_ctx { + struct bpf_prog *prog; + unsigned int *offset; + int idx; + int epilogue_offset; + 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; + u32 *image; +}; + +#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) + +/* Map BPF registers to SPARC registers */ +static const int bpf2sparc[] = { + /* return value from in-kernel function, and exit value from eBPF */ + [BPF_REG_0] = O5, + + /* arguments from eBPF program to in-kernel function */ + [BPF_REG_1] = O0, + [BPF_REG_2] = O1, + [BPF_REG_3] = O2, + [BPF_REG_4] = O3, + [BPF_REG_5] = O4, + + /* callee saved registers that in-kernel function will preserve */ + [BPF_REG_6] = L0, + [BPF_REG_7] = L1, + [BPF_REG_8] = L2, + [BPF_REG_9] = L3, + + /* read-only frame pointer to access stack */ + [BPF_REG_FP] = L6, + + [BPF_REG_AX] = G7, + + /* temporary register for internal BPF JIT */ + [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) +{ + if (ctx->image != NULL) + ctx->image[ctx->idx] = insn; + + ctx->idx++; +} + +static void emit_call(u32 *func, struct jit_ctx *ctx) +{ + if (ctx->image != NULL) { + void *here = &ctx->image[ctx->idx]; + unsigned int off; + + off = (void *)func - here; + ctx->image[ctx->idx] = CALL | ((off >> 2) & 0x3fffffff); + } + ctx->idx++; +} + +static void emit_nop(struct jit_ctx *ctx) +{ + emit(SETHI(0, G0), ctx); +} + +static void emit_reg_move(u32 from, u32 to, struct jit_ctx *ctx) +{ + emit(OR | RS1(G0) | RS2(from) | RD(to), ctx); +} + +/* Emit 32-bit constant, zero extended. */ +static void emit_set_const(s32 K, u32 reg, struct jit_ctx *ctx) +{ + emit(SETHI(K, reg), ctx); + emit(OR_LO(K, reg), ctx); +} + +/* Emit 32-bit constant, sign extended. */ +static void emit_set_const_sext(s32 K, u32 reg, struct jit_ctx *ctx) +{ + if (K >= 0) { + emit(SETHI(K, reg), ctx); + emit(OR_LO(K, reg), ctx); + } else { + u32 hbits = ~(u32) K; + u32 lbits = -0x400 | (u32) K; + + emit(SETHI(hbits, reg), ctx); + emit(XOR | IMMED | RS1(reg) | S13(lbits) | RD(reg), ctx); + } +} + +static void emit_alu(u32 opcode, u32 src, u32 dst, struct jit_ctx *ctx) +{ + emit(opcode | RS1(dst) | RS2(src) | RD(dst), ctx); +} + +static void emit_alu3(u32 opcode, u32 a, u32 b, u32 c, struct jit_ctx *ctx) +{ + emit(opcode | RS1(a) | RS2(b) | RD(c), ctx); +} + +static void emit_alu_K(unsigned int opcode, unsigned int dst, unsigned int imm, + struct jit_ctx *ctx) +{ + bool small_immed = is_simm13(imm); + unsigned int insn = opcode; + + insn |= RS1(dst) | RD(dst); + if (small_immed) { + emit(insn | IMMED | S13(imm), ctx); + } else { + unsigned int tmp = bpf2sparc[TMP_REG_1]; + + ctx->tmp_1_used = true; + + emit_set_const_sext(imm, tmp, ctx); + emit(insn | RS2(tmp), ctx); + } +} + +static void emit_alu3_K(unsigned int opcode, unsigned int src, unsigned int imm, + unsigned int dst, struct jit_ctx *ctx) +{ + bool small_immed = is_simm13(imm); + unsigned int insn = opcode; + + insn |= RS1(src) | RD(dst); + if (small_immed) { + emit(insn | IMMED | S13(imm), ctx); + } else { + unsigned int tmp = bpf2sparc[TMP_REG_1]; + + ctx->tmp_1_used = true; + + emit_set_const_sext(imm, tmp, ctx); + emit(insn | RS2(tmp), ctx); + } +} + +static void emit_loadimm32(s32 K, unsigned int dest, struct jit_ctx *ctx) +{ + if (K >= 0 && is_simm13(K)) { + /* or %g0, K, DEST */ + emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx); + } else { + emit_set_const(K, dest, ctx); + } +} + +static void emit_loadimm(s32 K, unsigned int dest, struct jit_ctx *ctx) +{ + if (is_simm13(K)) { + /* or %g0, K, DEST */ + emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx); + } else { + emit_set_const(K, dest, ctx); + } +} + +static void emit_loadimm_sext(s32 K, unsigned int dest, struct jit_ctx *ctx) +{ + if (is_simm13(K)) { + /* or %g0, K, DEST */ + emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx); + } else { + emit_set_const_sext(K, dest, ctx); + } +} + +static void analyze_64bit_constant(u32 high_bits, u32 low_bits, + int *hbsp, int *lbsp, int *abbasp) +{ + int lowest_bit_set, highest_bit_set, all_bits_between_are_set; + int i; + + lowest_bit_set = highest_bit_set = -1; + i = 0; + do { + if ((lowest_bit_set == -1) && ((low_bits >> i) & 1)) + lowest_bit_set = i; + if ((highest_bit_set == -1) && ((high_bits >> (32 - i - 1)) & 1)) + highest_bit_set = (64 - i - 1); + } while (++i < 32 && (highest_bit_set == -1 || + lowest_bit_set == -1)); + if (i == 32) { + i = 0; + do { + if (lowest_bit_set == -1 && ((high_bits >> i) & 1)) + lowest_bit_set = i + 32; + if (highest_bit_set == -1 && + ((low_bits >> (32 - i - 1)) & 1)) + highest_bit_set = 32 - i - 1; + } while (++i < 32 && (highest_bit_set == -1 || + lowest_bit_set == -1)); + } + + all_bits_between_are_set = 1; + for (i = lowest_bit_set; i <= highest_bit_set; i++) { + if (i < 32) { + if ((low_bits & (1 << i)) != 0) + continue; + } else { + if ((high_bits & (1 << (i - 32))) != 0) + continue; + } + all_bits_between_are_set = 0; + break; + } + *hbsp = highest_bit_set; + *lbsp = lowest_bit_set; + *abbasp = all_bits_between_are_set; +} + +static unsigned long create_simple_focus_bits(unsigned long high_bits, + unsigned long low_bits, + int lowest_bit_set, int shift) +{ + long hi, lo; + + if (lowest_bit_set < 32) { + lo = (low_bits >> lowest_bit_set) << shift; + hi = ((high_bits << (32 - lowest_bit_set)) << shift); + } else { + lo = 0; + hi = ((high_bits >> (lowest_bit_set - 32)) << shift); + } + return hi | lo; +} + +static bool const64_is_2insns(unsigned long high_bits, + unsigned long low_bits) +{ + int highest_bit_set, lowest_bit_set, all_bits_between_are_set; + + if (high_bits == 0 || high_bits == 0xffffffff) + return true; + + analyze_64bit_constant(high_bits, low_bits, + &highest_bit_set, &lowest_bit_set, + &all_bits_between_are_set); + + if ((highest_bit_set == 63 || lowest_bit_set == 0) && + all_bits_between_are_set != 0) + return true; + + if (highest_bit_set - lowest_bit_set < 21) + return true; + + return false; +} + +static void sparc_emit_set_const64_quick2(unsigned long high_bits, + unsigned long low_imm, + unsigned int dest, + int shift_count, struct jit_ctx *ctx) +{ + emit_loadimm32(high_bits, dest, ctx); + + /* Now shift it up into place. */ + emit_alu_K(SLLX, dest, shift_count, ctx); + + /* If there is a low immediate part piece, finish up by + * putting that in as well. + */ + if (low_imm != 0) + emit(OR | IMMED | RS1(dest) | S13(low_imm) | RD(dest), ctx); +} + +static void emit_loadimm64(u64 K, unsigned int dest, struct jit_ctx *ctx) +{ + int all_bits_between_are_set, lowest_bit_set, highest_bit_set; + unsigned int tmp = bpf2sparc[TMP_REG_1]; + u32 low_bits = (K & 0xffffffff); + u32 high_bits = (K >> 32); + + /* These two tests also take care of all of the one + * instruction cases. + */ + if (high_bits == 0xffffffff && (low_bits & 0x80000000)) + return emit_loadimm_sext(K, dest, ctx); + if (high_bits == 0x00000000) + return emit_loadimm32(K, dest, ctx); + + analyze_64bit_constant(high_bits, low_bits, &highest_bit_set, + &lowest_bit_set, &all_bits_between_are_set); + + /* 1) mov -1, %reg + * sllx %reg, shift, %reg + * 2) mov -1, %reg + * srlx %reg, shift, %reg + * 3) mov some_small_const, %reg + * sllx %reg, shift, %reg + */ + if (((highest_bit_set == 63 || lowest_bit_set == 0) && + all_bits_between_are_set != 0) || + ((highest_bit_set - lowest_bit_set) < 12)) { + int shift = lowest_bit_set; + long the_const = -1; + + if ((highest_bit_set != 63 && lowest_bit_set != 0) || + all_bits_between_are_set == 0) { + the_const = + create_simple_focus_bits(high_bits, low_bits, + lowest_bit_set, 0); + } else if (lowest_bit_set == 0) + shift = -(63 - highest_bit_set); + + emit(OR | IMMED | RS1(G0) | S13(the_const) | RD(dest), ctx); + if (shift > 0) + emit_alu_K(SLLX, dest, shift, ctx); + else if (shift < 0) + emit_alu_K(SRLX, dest, -shift, ctx); + + return; + } + + /* Now a range of 22 or less bits set somewhere. + * 1) sethi %hi(focus_bits), %reg + * sllx %reg, shift, %reg + * 2) sethi %hi(focus_bits), %reg + * srlx %reg, shift, %reg + */ + if ((highest_bit_set - lowest_bit_set) < 21) { + unsigned long focus_bits = + create_simple_focus_bits(high_bits, low_bits, + lowest_bit_set, 10); + + emit(SETHI(focus_bits, dest), ctx); + + /* If lowest_bit_set == 10 then a sethi alone could + * have done it. + */ + if (lowest_bit_set < 10) + emit_alu_K(SRLX, dest, 10 - lowest_bit_set, ctx); + else if (lowest_bit_set > 10) + emit_alu_K(SLLX, dest, lowest_bit_set - 10, ctx); + return; + } + + /* Ok, now 3 instruction sequences. */ + if (low_bits == 0) { + emit_loadimm32(high_bits, dest, ctx); + emit_alu_K(SLLX, dest, 32, ctx); + return; + } + + /* We may be able to do something quick + * when the constant is negated, so try that. + */ + if (const64_is_2insns((~high_bits) & 0xffffffff, + (~low_bits) & 0xfffffc00)) { + /* NOTE: The trailing bits get XOR'd so we need the + * non-negated bits, not the negated ones. + */ + unsigned long trailing_bits = low_bits & 0x3ff; + + if ((((~high_bits) & 0xffffffff) == 0 && + ((~low_bits) & 0x80000000) == 0) || + (((~high_bits) & 0xffffffff) == 0xffffffff && + ((~low_bits) & 0x80000000) != 0)) { + unsigned long fast_int = (~low_bits & 0xffffffff); + + if ((is_sethi(fast_int) && + (~high_bits & 0xffffffff) == 0)) { + emit(SETHI(fast_int, dest), ctx); + } else if (is_simm13(fast_int)) { + emit(OR | IMMED | RS1(G0) | S13(fast_int) | RD(dest), ctx); + } else { + emit_loadimm64(fast_int, dest, ctx); + } + } else { + u64 n = ((~low_bits) & 0xfffffc00) | + (((unsigned long)((~high_bits) & 0xffffffff))<<32); + emit_loadimm64(n, dest, ctx); + } + + low_bits = -0x400 | trailing_bits; + + emit(XOR | IMMED | RS1(dest) | S13(low_bits) | RD(dest), ctx); + return; + } + + /* 1) sethi %hi(xxx), %reg + * or %reg, %lo(xxx), %reg + * sllx %reg, yyy, %reg + */ + if ((highest_bit_set - lowest_bit_set) < 32) { + unsigned long focus_bits = + create_simple_focus_bits(high_bits, low_bits, + lowest_bit_set, 0); + + /* So what we know is that the set bits straddle the + * middle of the 64-bit word. + */ + sparc_emit_set_const64_quick2(focus_bits, 0, dest, + lowest_bit_set, ctx); + return; + } + + /* 1) sethi %hi(high_bits), %reg + * or %reg, %lo(high_bits), %reg + * sllx %reg, 32, %reg + * or %reg, low_bits, %reg + */ + if (is_simm13(low_bits) && ((int)low_bits > 0)) { + sparc_emit_set_const64_quick2(high_bits, low_bits, + dest, 32, ctx); + return; + } + + /* Oh well, we tried... Do a full 64-bit decomposition. */ + ctx->tmp_1_used = true; + + emit_loadimm32(high_bits, tmp, ctx); + emit_loadimm32(low_bits, dest, ctx); + emit_alu_K(SLLX, tmp, 32, ctx); + emit(OR | RS1(dest) | RS2(tmp) | RD(dest), ctx); +} + +static void emit_branch(unsigned int br_opc, unsigned int from_idx, unsigned int to_idx, + struct jit_ctx *ctx) +{ + unsigned int off = to_idx - from_idx; + + if (br_opc & XCC) + emit(br_opc | WDISP19(off << 2), ctx); + else + emit(br_opc | WDISP22(off << 2), ctx); +} + +static void emit_cbcond(unsigned int cb_opc, unsigned int from_idx, unsigned int to_idx, + const u8 dst, const u8 src, struct jit_ctx *ctx) +{ + unsigned int off = to_idx - from_idx; + + emit(cb_opc | WDISP10(off << 2) | RS1(dst) | RS2(src), ctx); +} + +static void emit_cbcondi(unsigned int cb_opc, unsigned int from_idx, unsigned int to_idx, + const u8 dst, s32 imm, struct jit_ctx *ctx) +{ + unsigned int off = to_idx - from_idx; + + emit(cb_opc | IMMED | WDISP10(off << 2) | RS1(dst) | S5(imm), ctx); +} + +#define emit_read_y(REG, CTX) emit(RD_Y | RD(REG), CTX) +#define emit_write_y(REG, CTX) emit(WR_Y | IMMED | RS1(REG) | S13(0), CTX) + +#define emit_cmp(R1, R2, CTX) \ + emit(SUBCC | RS1(R1) | RS2(R2) | RD(G0), CTX) + +#define emit_cmpi(R1, IMM, CTX) \ + emit(SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0), CTX) + +#define emit_btst(R1, R2, CTX) \ + emit(ANDCC | RS1(R1) | RS2(R2) | RD(G0), CTX) + +#define emit_btsti(R1, IMM, CTX) \ + emit(ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0), CTX) + +static int emit_compare_and_branch(const u8 code, const u8 dst, u8 src, + const s32 imm, bool is_imm, int branch_dst, + struct jit_ctx *ctx) +{ + bool use_cbcond = (sparc64_elf_hwcap & AV_SPARC_CBCOND) != 0; + const u8 tmp = bpf2sparc[TMP_REG_1]; + + branch_dst = ctx->offset[branch_dst]; + + if (!is_simm10(branch_dst - ctx->idx) || + BPF_OP(code) == BPF_JSET) + use_cbcond = false; + + if (is_imm) { + bool fits = true; + + if (use_cbcond) { + if (!is_simm5(imm)) + fits = false; + } else if (!is_simm13(imm)) { + fits = false; + } + if (!fits) { + ctx->tmp_1_used = true; + emit_loadimm_sext(imm, tmp, ctx); + src = tmp; + is_imm = false; + } + } + + if (!use_cbcond) { + u32 br_opcode; + + if (BPF_OP(code) == BPF_JSET) { + if (is_imm) + emit_btsti(dst, imm, ctx); + else + emit_btst(dst, src, ctx); + } else { + if (is_imm) + emit_cmpi(dst, imm, ctx); + else + emit_cmp(dst, src, ctx); + } + switch (BPF_OP(code)) { + case BPF_JEQ: + br_opcode = BE; + break; + case BPF_JGT: + br_opcode = BGU; + break; + case BPF_JGE: + br_opcode = BGEU; + break; + case BPF_JSET: + case BPF_JNE: + br_opcode = BNE; + break; + case BPF_JSGT: + br_opcode = BG; + break; + case BPF_JSGE: + br_opcode = BGE; + break; + default: + /* Make sure we dont leak kernel information to the + * user. + */ + return -EFAULT; + } + emit_branch(br_opcode, ctx->idx, branch_dst, ctx); + emit_nop(ctx); + } else { + u32 cbcond_opcode; + + switch (BPF_OP(code)) { + case BPF_JEQ: + cbcond_opcode = CBCONDE; + break; + case BPF_JGT: + cbcond_opcode = CBCONDGU; + break; + case BPF_JGE: + cbcond_opcode = CBCONDGEU; + break; + case BPF_JNE: + cbcond_opcode = CBCONDNE; + break; + case BPF_JSGT: + cbcond_opcode = CBCONDG; + break; + case BPF_JSGE: + cbcond_opcode = CBCONDGE; + break; + default: + /* Make sure we dont leak kernel information to the + * user. + */ + return -EFAULT; + } + cbcond_opcode |= CBCOND_OP; + if (is_imm) + emit_cbcondi(cbcond_opcode, ctx->idx, branch_dst, + dst, imm, ctx); + else + emit_cbcond(cbcond_opcode, ctx->idx, branch_dst, + dst, src, ctx); + } + 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) + +static void build_prologue(struct jit_ctx *ctx) +{ + s32 stack_needed = BASE_STACKFRAME; + + if (ctx->saw_frame_pointer || ctx->saw_tail_call) + stack_needed += MAX_BPF_STACK; + + if (ctx->saw_tail_call) + stack_needed += 8; + + /* save %sp, -176, %sp */ + emit(SAVE | IMMED | RS1(SP) | S13(-stack_needed) | RD(SP), ctx); + + /* tail_call_cnt = 0 */ + if (ctx->saw_tail_call) { + u32 off = BPF_TAILCALL_CNT_SP_OFF; + + emit(ST32 | IMMED | RS1(SP) | S13(off) | RD(G0), ctx); + } else { + emit_nop(ctx); + } + if (ctx->saw_frame_pointer) { + const u8 vfp = bpf2sparc[BPF_REG_FP]; + + emit(ADD | IMMED | RS1(FP) | S13(STACK_BIAS) | RD(vfp), 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) +{ + ctx->epilogue_offset = ctx->idx; + + /* ret (jmpl %i7 + 8, %g0) */ + emit(JMPL | IMMED | RS1(I7) | S13(8) | RD(G0), ctx); + + /* restore %i5, %g0, %o0 */ + emit(RESTORE | RS1(bpf2sparc[BPF_REG_0]) | RS2(G0) | RD(O0), ctx); +} + +static void emit_tail_call(struct jit_ctx *ctx) +{ + const u8 bpf_array = bpf2sparc[BPF_REG_2]; + const u8 bpf_index = bpf2sparc[BPF_REG_3]; + const u8 tmp = bpf2sparc[TMP_REG_1]; + u32 off; + + ctx->saw_tail_call = true; + + off = offsetof(struct bpf_array, map.max_entries); + emit(LD32 | IMMED | RS1(bpf_array) | S13(off) | RD(tmp), ctx); + emit_cmp(bpf_index, tmp, ctx); +#define OFFSET1 17 + emit_branch(BGEU, ctx->idx, ctx->idx + OFFSET1, ctx); + emit_nop(ctx); + + off = BPF_TAILCALL_CNT_SP_OFF; + emit(LD32 | IMMED | RS1(SP) | S13(off) | RD(tmp), ctx); + emit_cmpi(tmp, MAX_TAIL_CALL_CNT, ctx); +#define OFFSET2 13 + emit_branch(BGU, ctx->idx, ctx->idx + OFFSET2, ctx); + emit_nop(ctx); + + emit_alu_K(ADD, tmp, 1, ctx); + off = BPF_TAILCALL_CNT_SP_OFF; + emit(ST32 | IMMED | RS1(SP) | S13(off) | RD(tmp), ctx); + + emit_alu3_K(SLL, bpf_index, 3, tmp, ctx); + emit_alu(ADD, bpf_array, tmp, ctx); + off = offsetof(struct bpf_array, ptrs); + emit(LD64 | IMMED | RS1(tmp) | S13(off) | RD(tmp), ctx); + + emit_cmpi(tmp, 0, ctx); +#define OFFSET3 5 + emit_branch(BE, ctx->idx, ctx->idx + OFFSET3, ctx); + emit_nop(ctx); + + off = offsetof(struct bpf_prog, bpf_func); + emit(LD64 | IMMED | RS1(tmp) | S13(off) | RD(tmp), ctx); + + off = BPF_TAILCALL_PROLOGUE_SKIP; + emit(JMPL | IMMED | RS1(tmp) | S13(off) | RD(G0), ctx); + emit_nop(ctx); +} + +static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx) +{ + const u8 code = insn->code; + const u8 dst = bpf2sparc[insn->dst_reg]; + const u8 src = bpf2sparc[insn->src_reg]; + const int i = insn - ctx->prog->insnsi; + const s16 off = insn->off; + const s32 imm = insn->imm; + u32 *func; + + if (insn->src_reg == BPF_REG_FP) + ctx->saw_frame_pointer = true; + + switch (code) { + /* dst = src */ + case BPF_ALU | BPF_MOV | BPF_X: + emit_alu3_K(SRL, src, 0, dst, ctx); + break; + case BPF_ALU64 | BPF_MOV | BPF_X: + emit_reg_move(src, dst, ctx); + break; + /* dst = dst OP src */ + case BPF_ALU | BPF_ADD | BPF_X: + case BPF_ALU64 | BPF_ADD | BPF_X: + emit_alu(ADD, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_SUB | BPF_X: + case BPF_ALU64 | BPF_SUB | BPF_X: + emit_alu(SUB, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_AND | BPF_X: + case BPF_ALU64 | BPF_AND | BPF_X: + emit_alu(AND, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_OR | BPF_X: + case BPF_ALU64 | BPF_OR | BPF_X: + emit_alu(OR, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_XOR | BPF_X: + case BPF_ALU64 | BPF_XOR | BPF_X: + emit_alu(XOR, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_MUL | BPF_X: + emit_alu(MUL, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_MUL | BPF_X: + emit_alu(MULX, src, dst, ctx); + break; + case BPF_ALU | BPF_DIV | BPF_X: + emit_cmp(src, G0, ctx); + emit_branch(BE|ANNUL, ctx->idx, ctx->epilogue_offset, ctx); + emit_loadimm(0, bpf2sparc[BPF_REG_0], ctx); + + emit_write_y(G0, ctx); + emit_alu(DIV, src, dst, ctx); + break; + + case BPF_ALU64 | BPF_DIV | BPF_X: + emit_cmp(src, G0, ctx); + emit_branch(BE|ANNUL, ctx->idx, ctx->epilogue_offset, ctx); + emit_loadimm(0, bpf2sparc[BPF_REG_0], ctx); + + emit_alu(UDIVX, src, dst, ctx); + break; + + case BPF_ALU | BPF_MOD | BPF_X: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + + ctx->tmp_1_used = true; + + emit_cmp(src, G0, ctx); + emit_branch(BE|ANNUL, ctx->idx, ctx->epilogue_offset, ctx); + emit_loadimm(0, bpf2sparc[BPF_REG_0], ctx); + + emit_write_y(G0, ctx); + emit_alu3(DIV, dst, src, tmp, ctx); + emit_alu3(MULX, tmp, src, tmp, ctx); + emit_alu3(SUB, dst, tmp, dst, ctx); + goto do_alu32_trunc; + } + case BPF_ALU64 | BPF_MOD | BPF_X: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + + ctx->tmp_1_used = true; + + emit_cmp(src, G0, ctx); + emit_branch(BE|ANNUL, ctx->idx, ctx->epilogue_offset, ctx); + emit_loadimm(0, bpf2sparc[BPF_REG_0], ctx); + + emit_alu3(UDIVX, dst, src, tmp, ctx); + emit_alu3(MULX, tmp, src, tmp, ctx); + emit_alu3(SUB, dst, tmp, dst, ctx); + break; + } + case BPF_ALU | BPF_LSH | BPF_X: + emit_alu(SLL, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_LSH | BPF_X: + emit_alu(SLLX, src, dst, ctx); + break; + case BPF_ALU | BPF_RSH | BPF_X: + emit_alu(SRL, src, dst, ctx); + break; + case BPF_ALU64 | BPF_RSH | BPF_X: + emit_alu(SRLX, src, dst, ctx); + break; + case BPF_ALU | BPF_ARSH | BPF_X: + emit_alu(SRA, src, dst, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_ARSH | BPF_X: + emit_alu(SRAX, src, dst, ctx); + break; + + /* dst = -dst */ + case BPF_ALU | BPF_NEG: + case BPF_ALU64 | BPF_NEG: + emit(SUB | RS1(0) | RS2(dst) | RD(dst), ctx); + goto do_alu32_trunc; + + case BPF_ALU | BPF_END | BPF_FROM_BE: + switch (imm) { + case 16: + emit_alu_K(SLL, dst, 16, ctx); + emit_alu_K(SRL, dst, 16, ctx); + break; + case 32: + emit_alu_K(SRL, dst, 0, ctx); + break; + case 64: + /* nop */ + break; + + } + break; + + /* dst = BSWAP##imm(dst) */ + case BPF_ALU | BPF_END | BPF_FROM_LE: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + const u8 tmp2 = bpf2sparc[TMP_REG_2]; + + ctx->tmp_1_used = true; + switch (imm) { + case 16: + emit_alu3_K(AND, dst, 0xff, tmp, ctx); + emit_alu3_K(SRL, dst, 8, dst, ctx); + emit_alu3_K(AND, dst, 0xff, dst, ctx); + emit_alu3_K(SLL, tmp, 8, tmp, ctx); + emit_alu(OR, tmp, dst, ctx); + break; + + case 32: + ctx->tmp_2_used = true; + emit_alu3_K(SRL, dst, 24, tmp, ctx); /* tmp = dst >> 24 */ + emit_alu3_K(SRL, dst, 16, tmp2, ctx); /* tmp2 = dst >> 16 */ + emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */ + emit_alu3_K(SLL, tmp2, 8, tmp2, ctx); /* tmp2 = tmp2 << 8 */ + emit_alu(OR, tmp2, tmp, ctx); /* tmp = tmp | tmp2 */ + emit_alu3_K(SRL, dst, 8, tmp2, ctx); /* tmp2 = dst >> 8 */ + emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */ + emit_alu3_K(SLL, tmp2, 16, tmp2, ctx); /* tmp2 = tmp2 << 16 */ + emit_alu(OR, tmp2, tmp, ctx); /* tmp = tmp | tmp2 */ + emit_alu3_K(AND, dst, 0xff, dst, ctx); /* dst = dst & 0xff */ + emit_alu3_K(SLL, dst, 24, dst, ctx); /* dst = dst << 24 */ + emit_alu(OR, tmp, dst, ctx); /* dst = dst | tmp */ + break; + + case 64: + emit_alu3_K(ADD, SP, STACK_BIAS + 128, tmp, ctx); + emit(ST64 | RS1(tmp) | RS2(G0) | RD(dst), ctx); + emit(LD64A | ASI(ASI_PL) | RS1(tmp) | RS2(G0) | RD(dst), ctx); + break; + } + break; + } + /* dst = imm */ + case BPF_ALU | BPF_MOV | BPF_K: + emit_loadimm32(imm, dst, ctx); + break; + case BPF_ALU64 | BPF_MOV | BPF_K: + emit_loadimm_sext(imm, dst, ctx); + break; + /* dst = dst OP imm */ + case BPF_ALU | BPF_ADD | BPF_K: + case BPF_ALU64 | BPF_ADD | BPF_K: + emit_alu_K(ADD, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_SUB | BPF_K: + case BPF_ALU64 | BPF_SUB | BPF_K: + emit_alu_K(SUB, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_AND | BPF_K: + case BPF_ALU64 | BPF_AND | BPF_K: + emit_alu_K(AND, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_OR | BPF_K: + case BPF_ALU64 | BPF_OR | BPF_K: + emit_alu_K(OR, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_XOR | BPF_K: + case BPF_ALU64 | BPF_XOR | BPF_K: + emit_alu_K(XOR, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU | BPF_MUL | BPF_K: + emit_alu_K(MUL, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_MUL | BPF_K: + emit_alu_K(MULX, dst, imm, ctx); + break; + case BPF_ALU | BPF_DIV | BPF_K: + if (imm == 0) + return -EINVAL; + + emit_write_y(G0, ctx); + emit_alu_K(DIV, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_DIV | BPF_K: + if (imm == 0) + return -EINVAL; + + emit_alu_K(UDIVX, dst, imm, ctx); + break; + case BPF_ALU64 | BPF_MOD | BPF_K: + case BPF_ALU | BPF_MOD | BPF_K: { + const u8 tmp = bpf2sparc[TMP_REG_2]; + unsigned int div; + + if (imm == 0) + return -EINVAL; + + div = (BPF_CLASS(code) == BPF_ALU64) ? UDIVX : DIV; + + ctx->tmp_2_used = true; + + if (BPF_CLASS(code) != BPF_ALU64) + emit_write_y(G0, ctx); + if (is_simm13(imm)) { + emit(div | IMMED | RS1(dst) | S13(imm) | RD(tmp), ctx); + emit(MULX | IMMED | RS1(tmp) | S13(imm) | RD(tmp), ctx); + emit(SUB | RS1(dst) | RS2(tmp) | RD(dst), ctx); + } else { + const u8 tmp1 = bpf2sparc[TMP_REG_1]; + + ctx->tmp_1_used = true; + + emit_set_const_sext(imm, tmp1, ctx); + emit(div | RS1(dst) | RS2(tmp1) | RD(tmp), ctx); + emit(MULX | RS1(tmp) | RS2(tmp1) | RD(tmp), ctx); + emit(SUB | RS1(dst) | RS2(tmp) | RD(dst), ctx); + } + goto do_alu32_trunc; + } + case BPF_ALU | BPF_LSH | BPF_K: + emit_alu_K(SLL, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_LSH | BPF_K: + emit_alu_K(SLLX, dst, imm, ctx); + break; + case BPF_ALU | BPF_RSH | BPF_K: + emit_alu_K(SRL, dst, imm, ctx); + break; + case BPF_ALU64 | BPF_RSH | BPF_K: + emit_alu_K(SRLX, dst, imm, ctx); + break; + case BPF_ALU | BPF_ARSH | BPF_K: + emit_alu_K(SRA, dst, imm, ctx); + goto do_alu32_trunc; + case BPF_ALU64 | BPF_ARSH | BPF_K: + emit_alu_K(SRAX, dst, imm, ctx); + break; + + do_alu32_trunc: + if (BPF_CLASS(code) == BPF_ALU) + emit_alu_K(SRL, dst, 0, ctx); + break; + + /* JUMP off */ + case BPF_JMP | BPF_JA: + emit_branch(BA, ctx->idx, ctx->offset[i + off], ctx); + emit_nop(ctx); + break; + /* IF (dst COND src) JUMP off */ + case BPF_JMP | BPF_JEQ | BPF_X: + case BPF_JMP | BPF_JGT | BPF_X: + case BPF_JMP | BPF_JGE | BPF_X: + case BPF_JMP | BPF_JNE | BPF_X: + case BPF_JMP | BPF_JSGT | BPF_X: + case BPF_JMP | BPF_JSGE | BPF_X: + case BPF_JMP | BPF_JSET | BPF_X: { + int err; + + err = emit_compare_and_branch(code, dst, src, 0, false, i + off, ctx); + if (err) + return err; + break; + } + /* IF (dst COND imm) JUMP off */ + case BPF_JMP | BPF_JEQ | BPF_K: + case BPF_JMP | BPF_JGT | BPF_K: + case BPF_JMP | BPF_JGE | BPF_K: + case BPF_JMP | BPF_JNE | BPF_K: + case BPF_JMP | BPF_JSGT | BPF_K: + case BPF_JMP | BPF_JSGE | BPF_K: + case BPF_JMP | BPF_JSET | BPF_K: { + int err; + + err = emit_compare_and_branch(code, dst, 0, imm, true, i + off, ctx); + if (err) + return err; + break; + } + + /* function call */ + case BPF_JMP | BPF_CALL: + { + u8 *func = ((u8 *)__bpf_call_base) + imm; + + ctx->saw_call = true; + + emit_call((u32 *)func, ctx); + emit_nop(ctx); + + emit_reg_move(O0, bpf2sparc[BPF_REG_0], ctx); + + if (bpf_helper_changes_pkt_data(func) && ctx->saw_ld_abs_ind) + load_skb_regs(ctx, bpf2sparc[BPF_REG_6]); + break; + } + + /* tail call */ + case BPF_JMP | BPF_CALL |BPF_X: + emit_tail_call(ctx); + break; + + /* function return */ + case BPF_JMP | BPF_EXIT: + /* Optimization: when last instruction is EXIT, + simply fallthrough to epilogue. */ + if (i == ctx->prog->len - 1) + break; + emit_branch(BA, ctx->idx, ctx->epilogue_offset, ctx); + emit_nop(ctx); + break; + + /* dst = imm64 */ + case BPF_LD | BPF_IMM | BPF_DW: + { + const struct bpf_insn insn1 = insn[1]; + u64 imm64; + + imm64 = (u64)insn1.imm << 32 | (u32)imm; + emit_loadimm64(imm64, dst, ctx); + + return 1; + } + + /* LDX: dst = *(size *)(src + off) */ + case BPF_LDX | BPF_MEM | BPF_W: + case BPF_LDX | BPF_MEM | BPF_H: + case BPF_LDX | BPF_MEM | BPF_B: + case BPF_LDX | BPF_MEM | BPF_DW: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + u32 opcode = 0, rs2; + + ctx->tmp_1_used = true; + switch (BPF_SIZE(code)) { + case BPF_W: + opcode = LD32; + break; + case BPF_H: + opcode = LD16; + break; + case BPF_B: + opcode = LD8; + break; + case BPF_DW: + opcode = LD64; + break; + } + + if (is_simm13(off)) { + opcode |= IMMED; + rs2 = S13(off); + } else { + emit_loadimm(off, tmp, ctx); + rs2 = RS2(tmp); + } + emit(opcode | RS1(src) | rs2 | RD(dst), ctx); + break; + } + /* ST: *(size *)(dst + off) = imm */ + case BPF_ST | BPF_MEM | BPF_W: + case BPF_ST | BPF_MEM | BPF_H: + case BPF_ST | BPF_MEM | BPF_B: + case BPF_ST | BPF_MEM | BPF_DW: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + const u8 tmp2 = bpf2sparc[TMP_REG_2]; + u32 opcode = 0, rs2; + + ctx->tmp_2_used = true; + emit_loadimm(imm, tmp2, ctx); + + switch (BPF_SIZE(code)) { + case BPF_W: + opcode = ST32; + break; + case BPF_H: + opcode = ST16; + break; + case BPF_B: + opcode = ST8; + break; + case BPF_DW: + opcode = ST64; + break; + } + + if (is_simm13(off)) { + opcode |= IMMED; + rs2 = S13(off); + } else { + ctx->tmp_1_used = true; + emit_loadimm(off, tmp, ctx); + rs2 = RS2(tmp); + } + emit(opcode | RS1(dst) | rs2 | RD(tmp2), ctx); + break; + } + + /* STX: *(size *)(dst + off) = src */ + case BPF_STX | BPF_MEM | BPF_W: + case BPF_STX | BPF_MEM | BPF_H: + case BPF_STX | BPF_MEM | BPF_B: + case BPF_STX | BPF_MEM | BPF_DW: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + u32 opcode = 0, rs2; + + switch (BPF_SIZE(code)) { + case BPF_W: + opcode = ST32; + break; + case BPF_H: + opcode = ST16; + break; + case BPF_B: + opcode = ST8; + break; + case BPF_DW: + opcode = ST64; + break; + } + if (is_simm13(off)) { + opcode |= IMMED; + rs2 = S13(off); + } else { + ctx->tmp_1_used = true; + emit_loadimm(off, tmp, ctx); + rs2 = RS2(tmp); + } + emit(opcode | RS1(dst) | rs2 | RD(src), ctx); + break; + } + + /* STX XADD: lock *(u32 *)(dst + off) += src */ + case BPF_STX | BPF_XADD | BPF_W: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + const u8 tmp2 = bpf2sparc[TMP_REG_2]; + const u8 tmp3 = bpf2sparc[TMP_REG_3]; + + ctx->tmp_1_used = true; + ctx->tmp_2_used = true; + ctx->tmp_3_used = true; + emit_loadimm(off, tmp, ctx); + emit_alu3(ADD, dst, tmp, tmp, ctx); + + emit(LD32 | RS1(tmp) | RS2(G0) | RD(tmp2), ctx); + emit_alu3(ADD, tmp2, src, tmp3, ctx); + emit(CAS | ASI(ASI_P) | RS1(tmp) | RS2(tmp2) | RD(tmp3), ctx); + emit_cmp(tmp2, tmp3, ctx); + emit_branch(BNE, 4, 0, ctx); + emit_nop(ctx); + break; + } + /* STX XADD: lock *(u64 *)(dst + off) += src */ + case BPF_STX | BPF_XADD | BPF_DW: { + const u8 tmp = bpf2sparc[TMP_REG_1]; + const u8 tmp2 = bpf2sparc[TMP_REG_2]; + const u8 tmp3 = bpf2sparc[TMP_REG_3]; + + ctx->tmp_1_used = true; + ctx->tmp_2_used = true; + ctx->tmp_3_used = true; + emit_loadimm(off, tmp, ctx); + emit_alu3(ADD, dst, tmp, tmp, ctx); + + emit(LD64 | RS1(tmp) | RS2(G0) | RD(tmp2), ctx); + emit_alu3(ADD, tmp2, src, tmp3, ctx); + emit(CASX | ASI(ASI_P) | RS1(tmp) | RS2(tmp2) | RD(tmp3), ctx); + emit_cmp(tmp2, tmp3, ctx); + emit_branch(BNE, 4, 0, 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); + return -EINVAL; + } + + return 0; +} + +static int build_body(struct jit_ctx *ctx) +{ + const struct bpf_prog *prog = ctx->prog; + int i; + + for (i = 0; i < prog->len; i++) { + const struct bpf_insn *insn = &prog->insnsi[i]; + int ret; + + ret = build_insn(insn, ctx); + + if (ret > 0) { + i++; + ctx->offset[i] = ctx->idx; + continue; + } + ctx->offset[i] = ctx->idx; + if (ret) + return ret; + } + return 0; +} + +static void jit_fill_hole(void *area, unsigned int size) +{ + u32 *ptr; + /* We are guaranteed to have aligned memory. */ + for (ptr = area; size >= sizeof(u32); size -= sizeof(u32)) + *ptr++ = 0x91d02005; /* ta 5 */ +} + +struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) +{ + struct bpf_prog *tmp, *orig_prog = prog; + struct bpf_binary_header *header; + bool tmp_blinded = false; + struct jit_ctx ctx; + u32 image_size; + u8 *image_ptr; + int pass; + + if (!bpf_jit_enable) + return orig_prog; + + tmp = bpf_jit_blind_constants(prog); + /* If blinding was requested and we failed during blinding, + * we must fall back to the interpreter. + */ + if (IS_ERR(tmp)) + return orig_prog; + if (tmp != prog) { + tmp_blinded = true; + prog = tmp; + } + + memset(&ctx, 0, sizeof(ctx)); + ctx.prog = prog; + + ctx.offset = kcalloc(prog->len, sizeof(unsigned int), GFP_KERNEL); + if (ctx.offset == NULL) { + prog = orig_prog; + goto out; + } + + /* Fake pass to detect features used, and get an accurate assessment + * of what the final image size will be. + */ + if (build_body(&ctx)) { + prog = orig_prog; + goto out_off; + } + build_prologue(&ctx); + build_epilogue(&ctx); + + /* Now we know the actual image size. */ + image_size = sizeof(u32) * ctx.idx; + header = bpf_jit_binary_alloc(image_size, &image_ptr, + sizeof(u32), jit_fill_hole); + if (header == NULL) { + prog = orig_prog; + goto out_off; + } + + ctx.image = (u32 *)image_ptr; + + for (pass = 1; pass < 3; pass++) { + ctx.idx = 0; + + build_prologue(&ctx); + + if (build_body(&ctx)) { + bpf_jit_binary_free(header); + prog = orig_prog; + goto out_off; + } + + build_epilogue(&ctx); + + if (bpf_jit_enable > 1) + pr_info("Pass %d: shrink = %d, seen = [%c%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' : ' '); + } + + if (bpf_jit_enable > 1) + bpf_jit_dump(prog->len, image_size, pass, ctx.image); + + bpf_flush_icache(header, (u8 *)header + (header->pages * PAGE_SIZE)); + + bpf_jit_binary_lock_ro(header); + + prog->bpf_func = (void *)ctx.image; + prog->jited = 1; + +out_off: + kfree(ctx.offset); +out: + if (tmp_blinded) + bpf_jit_prog_release_other(prog, prog == orig_prog ? + tmp : orig_prog); + return prog; +} |