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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/arch/sparc/net/bpf_jit_comp_64.c

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38 KiB
C
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// SPDX-License-Identifier: GPL-2.0
#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"
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 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 BL (BRANCH | CONDL)
#define BLE (BRANCH | CONDLE)
#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_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 TMP_REG_3 (MAX_BPF_JIT_REG + 2)
/* 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,
};
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_JLT:
br_opcode = BLU;
break;
case BPF_JGE:
br_opcode = BGEU;
break;
case BPF_JLE:
br_opcode = BLEU;
break;
case BPF_JSET:
case BPF_JNE:
br_opcode = BNE;
break;
case BPF_JSGT:
br_opcode = BG;
break;
case BPF_JSLT:
br_opcode = BL;
break;
case BPF_JSGE:
br_opcode = BGE;
break;
case BPF_JSLE:
br_opcode = BLE;
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_JLT:
cbcond_opcode = CBCONDLU;
break;
case BPF_JGE:
cbcond_opcode = CBCONDGEU;
break;
case BPF_JLE:
cbcond_opcode = CBCONDLEU;
break;
case BPF_JNE:
cbcond_opcode = CBCONDNE;
break;
case BPF_JSGT:
cbcond_opcode = CBCONDG;
break;
case BPF_JSLT:
cbcond_opcode = CBCONDL;
break;
case BPF_JSGE:
cbcond_opcode = CBCONDGE;
break;
case BPF_JSLE:
cbcond_opcode = CBCONDLE;
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;
}
/* Just skip the save instruction and the ctx register move. */
#define BPF_TAILCALL_PROLOGUE_SKIP 32
#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) {
struct bpf_prog *prog = ctx->prog;
u32 stack_depth;
stack_depth = prog->aux->stack_depth;
stack_needed += round_up(stack_depth, 16);
}
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);
} else {
emit_nop(ctx);
}
emit_reg_move(I0, O0, ctx);
emit_reg_move(I1, O1, ctx);
emit_reg_move(I2, O2, ctx);
emit_reg_move(I3, O3, ctx);
emit_reg_move(I4, O4, ctx);
/* If you add anything here, adjust BPF_TAILCALL_PROLOGUE_SKIP above. */
}
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;
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);
if (insn_is_zext(&insn[1]))
return 1;
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_write_y(G0, ctx);
emit_alu(DIV, src, dst, ctx);
if (insn_is_zext(&insn[1]))
return 1;
break;
case BPF_ALU64 | BPF_DIV | BPF_X:
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_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_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);
if (insn_is_zext(&insn[1]))
return 1;
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);
if (insn_is_zext(&insn[1]))
return 1;
break;
case 32:
if (!ctx->prog->aux->verifier_zext)
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);
if (insn_is_zext(&insn[1]))
return 1;
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 */
if (insn_is_zext(&insn[1]))
return 1;
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);
if (insn_is_zext(&insn[1]))
return 1;
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);
if (insn_is_zext(&insn[1]))
return 1;
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 &&
!ctx->prog->aux->verifier_zext)
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_JLT | BPF_X:
case BPF_JMP | BPF_JGE | BPF_X:
case BPF_JMP | BPF_JLE | BPF_X:
case BPF_JMP | BPF_JNE | BPF_X:
case BPF_JMP | BPF_JSGT | BPF_X:
case BPF_JMP | BPF_JSLT | BPF_X:
case BPF_JMP | BPF_JSGE | BPF_X:
case BPF_JMP | BPF_JSLE | 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_JLT | BPF_K:
case BPF_JMP | BPF_JGE | BPF_K:
case BPF_JMP | BPF_JLE | BPF_K:
case BPF_JMP | BPF_JNE | BPF_K:
case BPF_JMP | BPF_JSGT | BPF_K:
case BPF_JMP | BPF_JSLT | BPF_K:
case BPF_JMP | BPF_JSGE | BPF_K:
case BPF_JMP | BPF_JSLE | 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);
break;
}
/* tail call */
case BPF_JMP | BPF_TAIL_CALL:
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);
if (opcode != LD64 && insn_is_zext(&insn[1]))
return 1;
break;
}
/* speculation barrier */
case BPF_ST | BPF_NOSPEC:
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;
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
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;
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
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;
}
case BPF_STX | BPF_ATOMIC | BPF_W: {
const u8 tmp = bpf2sparc[TMP_REG_1];
const u8 tmp2 = bpf2sparc[TMP_REG_2];
const u8 tmp3 = bpf2sparc[TMP_REG_3];
if (insn->imm != BPF_ADD) {
pr_err_once("unknown atomic op %02x\n", insn->imm);
return -EINVAL;
}
/* lock *(u32 *)(dst + off) += src */
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
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_ATOMIC | BPF_DW: {
const u8 tmp = bpf2sparc[TMP_REG_1];
const u8 tmp2 = bpf2sparc[TMP_REG_2];
const u8 tmp3 = bpf2sparc[TMP_REG_3];
if (insn->imm != BPF_ADD) {
pr_err_once("unknown atomic op %02x\n", insn->imm);
return -EINVAL;
}
if (insn->dst_reg == BPF_REG_FP)
ctx->saw_frame_pointer = true;
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;
}
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 */
}
bool bpf_jit_needs_zext(void)
{
return true;
}
struct sparc64_jit_data {
struct bpf_binary_header *header;
u8 *image;
struct jit_ctx ctx;
};
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
{
struct bpf_prog *tmp, *orig_prog = prog;
struct sparc64_jit_data *jit_data;
struct bpf_binary_header *header;
u32 prev_image_size, image_size;
bool tmp_blinded = false;
bool extra_pass = false;
struct jit_ctx ctx;
u8 *image_ptr;
int pass, i;
if (!prog->jit_requested)
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;
}
jit_data = prog->aux->jit_data;
if (!jit_data) {
jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
if (!jit_data) {
prog = orig_prog;
goto out;
}
prog->aux->jit_data = jit_data;
}
if (jit_data->ctx.offset) {
ctx = jit_data->ctx;
image_ptr = jit_data->image;
header = jit_data->header;
extra_pass = true;
image_size = sizeof(u32) * ctx.idx;
prev_image_size = image_size;
pass = 1;
goto skip_init_ctx;
}
memset(&ctx, 0, sizeof(ctx));
ctx.prog = prog;
ctx.offset = kmalloc_array(prog->len, sizeof(unsigned int), GFP_KERNEL);
if (ctx.offset == NULL) {
prog = orig_prog;
goto out_off;
}
/* Longest sequence emitted is for bswap32, 12 instructions. Pre-cook
* the offset array so that we converge faster.
*/
for (i = 0; i < prog->len; i++)
ctx.offset[i] = i * (12 * 4);
prev_image_size = ~0U;
for (pass = 1; pass < 40; pass++) {
ctx.idx = 0;
build_prologue(&ctx);
if (build_body(&ctx)) {
prog = orig_prog;
goto out_off;
}
build_epilogue(&ctx);
if (bpf_jit_enable > 1)
pr_info("Pass %d: size = %u, seen = [%c%c%c%c%c%c]\n", pass,
ctx.idx * 4,
ctx.tmp_1_used ? '1' : ' ',
ctx.tmp_2_used ? '2' : ' ',
ctx.tmp_3_used ? '3' : ' ',
ctx.saw_frame_pointer ? 'F' : ' ',
ctx.saw_call ? 'C' : ' ',
ctx.saw_tail_call ? 'T' : ' ');
if (ctx.idx * 4 == prev_image_size)
break;
prev_image_size = ctx.idx * 4;
cond_resched();
}
/* 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;
skip_init_ctx:
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 (ctx.idx * 4 != prev_image_size) {
pr_err("bpf_jit: Failed to converge, prev_size=%u size=%d\n",
prev_image_size, ctx.idx * 4);
bpf_jit_binary_free(header);
prog = orig_prog;
goto out_off;
}
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));
if (!prog->is_func || extra_pass) {
bpf_jit_binary_lock_ro(header);
} else {
jit_data->ctx = ctx;
jit_data->image = image_ptr;
jit_data->header = header;
}
prog->bpf_func = (void *)ctx.image;
prog->jited = 1;
prog->jited_len = image_size;
if (!prog->is_func || extra_pass) {
bpf_prog_fill_jited_linfo(prog, ctx.offset);
out_off:
kfree(ctx.offset);
kfree(jit_data);
prog->aux->jit_data = NULL;
}
out:
if (tmp_blinded)
bpf_jit_prog_release_other(prog, prog == orig_prog ?
tmp : orig_prog);
return prog;
}
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