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1826 lines
48 KiB
1826 lines
48 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* |
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* BPF Jit compiler for s390. |
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* |
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* Minimum build requirements: |
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* |
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* - HAVE_MARCH_Z196_FEATURES: laal, laalg |
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* - HAVE_MARCH_Z10_FEATURES: msfi, cgrj, clgrj |
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* - HAVE_MARCH_Z9_109_FEATURES: alfi, llilf, clfi, oilf, nilf |
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* - PACK_STACK |
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* - 64BIT |
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* |
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* Copyright IBM Corp. 2012,2015 |
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* |
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* Author(s): Martin Schwidefsky <[email protected]> |
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* Michael Holzheu <[email protected]> |
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*/ |
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#define KMSG_COMPONENT "bpf_jit" |
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#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt |
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#include <linux/netdevice.h> |
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#include <linux/filter.h> |
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#include <linux/init.h> |
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#include <linux/bpf.h> |
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#include <linux/mm.h> |
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#include <linux/kernel.h> |
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#include <asm/cacheflush.h> |
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#include <asm/dis.h> |
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#include <asm/facility.h> |
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#include <asm/nospec-branch.h> |
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#include <asm/set_memory.h> |
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#include "bpf_jit.h" |
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struct bpf_jit { |
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u32 seen; /* Flags to remember seen eBPF instructions */ |
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u32 seen_reg[16]; /* Array to remember which registers are used */ |
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u32 *addrs; /* Array with relative instruction addresses */ |
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u8 *prg_buf; /* Start of program */ |
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int size; /* Size of program and literal pool */ |
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int size_prg; /* Size of program */ |
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int prg; /* Current position in program */ |
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int lit32_start; /* Start of 32-bit literal pool */ |
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int lit32; /* Current position in 32-bit literal pool */ |
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int lit64_start; /* Start of 64-bit literal pool */ |
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int lit64; /* Current position in 64-bit literal pool */ |
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int base_ip; /* Base address for literal pool */ |
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int exit_ip; /* Address of exit */ |
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int r1_thunk_ip; /* Address of expoline thunk for 'br %r1' */ |
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int r14_thunk_ip; /* Address of expoline thunk for 'br %r14' */ |
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int tail_call_start; /* Tail call start offset */ |
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int excnt; /* Number of exception table entries */ |
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}; |
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#define SEEN_MEM BIT(0) /* use mem[] for temporary storage */ |
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#define SEEN_LITERAL BIT(1) /* code uses literals */ |
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#define SEEN_FUNC BIT(2) /* calls C functions */ |
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#define SEEN_TAIL_CALL BIT(3) /* code uses tail calls */ |
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#define SEEN_STACK (SEEN_FUNC | SEEN_MEM) |
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/* |
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* s390 registers |
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*/ |
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#define REG_W0 (MAX_BPF_JIT_REG + 0) /* Work register 1 (even) */ |
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#define REG_W1 (MAX_BPF_JIT_REG + 1) /* Work register 2 (odd) */ |
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#define REG_L (MAX_BPF_JIT_REG + 2) /* Literal pool register */ |
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#define REG_15 (MAX_BPF_JIT_REG + 3) /* Register 15 */ |
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#define REG_0 REG_W0 /* Register 0 */ |
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#define REG_1 REG_W1 /* Register 1 */ |
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#define REG_2 BPF_REG_1 /* Register 2 */ |
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#define REG_14 BPF_REG_0 /* Register 14 */ |
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/* |
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* Mapping of BPF registers to s390 registers |
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*/ |
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static const int reg2hex[] = { |
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/* Return code */ |
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[BPF_REG_0] = 14, |
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/* Function parameters */ |
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[BPF_REG_1] = 2, |
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[BPF_REG_2] = 3, |
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[BPF_REG_3] = 4, |
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[BPF_REG_4] = 5, |
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[BPF_REG_5] = 6, |
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/* Call saved registers */ |
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[BPF_REG_6] = 7, |
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[BPF_REG_7] = 8, |
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[BPF_REG_8] = 9, |
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[BPF_REG_9] = 10, |
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/* BPF stack pointer */ |
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[BPF_REG_FP] = 13, |
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/* Register for blinding */ |
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[BPF_REG_AX] = 12, |
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/* Work registers for s390x backend */ |
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[REG_W0] = 0, |
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[REG_W1] = 1, |
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[REG_L] = 11, |
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[REG_15] = 15, |
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}; |
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static inline u32 reg(u32 dst_reg, u32 src_reg) |
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{ |
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return reg2hex[dst_reg] << 4 | reg2hex[src_reg]; |
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} |
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static inline u32 reg_high(u32 reg) |
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{ |
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return reg2hex[reg] << 4; |
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} |
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static inline void reg_set_seen(struct bpf_jit *jit, u32 b1) |
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{ |
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u32 r1 = reg2hex[b1]; |
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if (!jit->seen_reg[r1] && r1 >= 6 && r1 <= 15) |
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jit->seen_reg[r1] = 1; |
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} |
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#define REG_SET_SEEN(b1) \ |
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({ \ |
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reg_set_seen(jit, b1); \ |
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}) |
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#define REG_SEEN(b1) jit->seen_reg[reg2hex[(b1)]] |
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/* |
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* EMIT macros for code generation |
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*/ |
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#define _EMIT2(op) \ |
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({ \ |
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if (jit->prg_buf) \ |
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*(u16 *) (jit->prg_buf + jit->prg) = (op); \ |
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jit->prg += 2; \ |
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}) |
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#define EMIT2(op, b1, b2) \ |
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({ \ |
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_EMIT2((op) | reg(b1, b2)); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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}) |
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#define _EMIT4(op) \ |
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({ \ |
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if (jit->prg_buf) \ |
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*(u32 *) (jit->prg_buf + jit->prg) = (op); \ |
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jit->prg += 4; \ |
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}) |
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#define EMIT4(op, b1, b2) \ |
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({ \ |
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_EMIT4((op) | reg(b1, b2)); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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}) |
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#define EMIT4_RRF(op, b1, b2, b3) \ |
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({ \ |
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_EMIT4((op) | reg_high(b3) << 8 | reg(b1, b2)); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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REG_SET_SEEN(b3); \ |
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}) |
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#define _EMIT4_DISP(op, disp) \ |
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({ \ |
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unsigned int __disp = (disp) & 0xfff; \ |
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_EMIT4((op) | __disp); \ |
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}) |
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#define EMIT4_DISP(op, b1, b2, disp) \ |
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({ \ |
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_EMIT4_DISP((op) | reg_high(b1) << 16 | \ |
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reg_high(b2) << 8, (disp)); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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}) |
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#define EMIT4_IMM(op, b1, imm) \ |
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({ \ |
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unsigned int __imm = (imm) & 0xffff; \ |
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_EMIT4((op) | reg_high(b1) << 16 | __imm); \ |
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REG_SET_SEEN(b1); \ |
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}) |
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#define EMIT4_PCREL(op, pcrel) \ |
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({ \ |
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long __pcrel = ((pcrel) >> 1) & 0xffff; \ |
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_EMIT4((op) | __pcrel); \ |
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}) |
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#define EMIT4_PCREL_RIC(op, mask, target) \ |
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({ \ |
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int __rel = ((target) - jit->prg) / 2; \ |
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_EMIT4((op) | (mask) << 20 | (__rel & 0xffff)); \ |
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}) |
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#define _EMIT6(op1, op2) \ |
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({ \ |
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if (jit->prg_buf) { \ |
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*(u32 *) (jit->prg_buf + jit->prg) = (op1); \ |
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*(u16 *) (jit->prg_buf + jit->prg + 4) = (op2); \ |
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} \ |
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jit->prg += 6; \ |
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}) |
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#define _EMIT6_DISP(op1, op2, disp) \ |
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({ \ |
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unsigned int __disp = (disp) & 0xfff; \ |
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_EMIT6((op1) | __disp, op2); \ |
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}) |
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#define _EMIT6_DISP_LH(op1, op2, disp) \ |
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({ \ |
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u32 _disp = (u32) (disp); \ |
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unsigned int __disp_h = _disp & 0xff000; \ |
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unsigned int __disp_l = _disp & 0x00fff; \ |
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_EMIT6((op1) | __disp_l, (op2) | __disp_h >> 4); \ |
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}) |
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#define EMIT6_DISP_LH(op1, op2, b1, b2, b3, disp) \ |
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({ \ |
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_EMIT6_DISP_LH((op1) | reg(b1, b2) << 16 | \ |
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reg_high(b3) << 8, op2, disp); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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REG_SET_SEEN(b3); \ |
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}) |
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#define EMIT6_PCREL_RIEB(op1, op2, b1, b2, mask, target) \ |
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({ \ |
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unsigned int rel = (int)((target) - jit->prg) / 2; \ |
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_EMIT6((op1) | reg(b1, b2) << 16 | (rel & 0xffff), \ |
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(op2) | (mask) << 12); \ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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}) |
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#define EMIT6_PCREL_RIEC(op1, op2, b1, imm, mask, target) \ |
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({ \ |
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unsigned int rel = (int)((target) - jit->prg) / 2; \ |
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_EMIT6((op1) | (reg_high(b1) | (mask)) << 16 | \ |
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(rel & 0xffff), (op2) | ((imm) & 0xff) << 8); \ |
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REG_SET_SEEN(b1); \ |
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BUILD_BUG_ON(((unsigned long) (imm)) > 0xff); \ |
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}) |
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#define EMIT6_PCREL(op1, op2, b1, b2, i, off, mask) \ |
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({ \ |
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/* Branch instruction needs 6 bytes */ \ |
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int rel = (addrs[(i) + (off) + 1] - (addrs[(i) + 1] - 6)) / 2;\ |
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_EMIT6((op1) | reg(b1, b2) << 16 | (rel & 0xffff), (op2) | (mask));\ |
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REG_SET_SEEN(b1); \ |
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REG_SET_SEEN(b2); \ |
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}) |
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#define EMIT6_PCREL_RILB(op, b, target) \ |
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({ \ |
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unsigned int rel = (int)((target) - jit->prg) / 2; \ |
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_EMIT6((op) | reg_high(b) << 16 | rel >> 16, rel & 0xffff);\ |
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REG_SET_SEEN(b); \ |
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}) |
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#define EMIT6_PCREL_RIL(op, target) \ |
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({ \ |
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unsigned int rel = (int)((target) - jit->prg) / 2; \ |
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_EMIT6((op) | rel >> 16, rel & 0xffff); \ |
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}) |
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#define EMIT6_PCREL_RILC(op, mask, target) \ |
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({ \ |
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EMIT6_PCREL_RIL((op) | (mask) << 20, (target)); \ |
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}) |
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#define _EMIT6_IMM(op, imm) \ |
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({ \ |
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unsigned int __imm = (imm); \ |
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_EMIT6((op) | (__imm >> 16), __imm & 0xffff); \ |
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}) |
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#define EMIT6_IMM(op, b1, imm) \ |
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({ \ |
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_EMIT6_IMM((op) | reg_high(b1) << 16, imm); \ |
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REG_SET_SEEN(b1); \ |
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}) |
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#define _EMIT_CONST_U32(val) \ |
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({ \ |
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unsigned int ret; \ |
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ret = jit->lit32; \ |
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if (jit->prg_buf) \ |
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*(u32 *)(jit->prg_buf + jit->lit32) = (u32)(val);\ |
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jit->lit32 += 4; \ |
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ret; \ |
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}) |
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#define EMIT_CONST_U32(val) \ |
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({ \ |
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jit->seen |= SEEN_LITERAL; \ |
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_EMIT_CONST_U32(val) - jit->base_ip; \ |
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}) |
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#define _EMIT_CONST_U64(val) \ |
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({ \ |
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unsigned int ret; \ |
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ret = jit->lit64; \ |
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if (jit->prg_buf) \ |
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*(u64 *)(jit->prg_buf + jit->lit64) = (u64)(val);\ |
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jit->lit64 += 8; \ |
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ret; \ |
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}) |
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#define EMIT_CONST_U64(val) \ |
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({ \ |
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jit->seen |= SEEN_LITERAL; \ |
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_EMIT_CONST_U64(val) - jit->base_ip; \ |
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}) |
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#define EMIT_ZERO(b1) \ |
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({ \ |
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if (!fp->aux->verifier_zext) { \ |
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/* llgfr %dst,%dst (zero extend to 64 bit) */ \ |
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EMIT4(0xb9160000, b1, b1); \ |
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REG_SET_SEEN(b1); \ |
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} \ |
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}) |
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/* |
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* Return whether this is the first pass. The first pass is special, since we |
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* don't know any sizes yet, and thus must be conservative. |
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*/ |
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static bool is_first_pass(struct bpf_jit *jit) |
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{ |
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return jit->size == 0; |
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} |
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/* |
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* Return whether this is the code generation pass. The code generation pass is |
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* special, since we should change as little as possible. |
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*/ |
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static bool is_codegen_pass(struct bpf_jit *jit) |
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{ |
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return jit->prg_buf; |
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} |
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/* |
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* Return whether "rel" can be encoded as a short PC-relative offset |
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*/ |
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static bool is_valid_rel(int rel) |
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{ |
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return rel >= -65536 && rel <= 65534; |
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} |
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/* |
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* Return whether "off" can be reached using a short PC-relative offset |
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*/ |
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static bool can_use_rel(struct bpf_jit *jit, int off) |
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{ |
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return is_valid_rel(off - jit->prg); |
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} |
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/* |
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* Return whether given displacement can be encoded using |
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* Long-Displacement Facility |
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*/ |
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static bool is_valid_ldisp(int disp) |
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{ |
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return disp >= -524288 && disp <= 524287; |
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} |
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/* |
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* Return whether the next 32-bit literal pool entry can be referenced using |
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* Long-Displacement Facility |
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*/ |
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static bool can_use_ldisp_for_lit32(struct bpf_jit *jit) |
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{ |
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return is_valid_ldisp(jit->lit32 - jit->base_ip); |
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} |
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/* |
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* Return whether the next 64-bit literal pool entry can be referenced using |
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* Long-Displacement Facility |
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*/ |
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static bool can_use_ldisp_for_lit64(struct bpf_jit *jit) |
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{ |
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return is_valid_ldisp(jit->lit64 - jit->base_ip); |
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} |
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/* |
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* Fill whole space with illegal instructions |
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*/ |
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static void jit_fill_hole(void *area, unsigned int size) |
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{ |
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memset(area, 0, size); |
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} |
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/* |
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* Save registers from "rs" (register start) to "re" (register end) on stack |
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*/ |
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static void save_regs(struct bpf_jit *jit, u32 rs, u32 re) |
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{ |
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u32 off = STK_OFF_R6 + (rs - 6) * 8; |
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if (rs == re) |
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/* stg %rs,off(%r15) */ |
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_EMIT6(0xe300f000 | rs << 20 | off, 0x0024); |
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else |
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/* stmg %rs,%re,off(%r15) */ |
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_EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0024, off); |
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} |
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/* |
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* Restore registers from "rs" (register start) to "re" (register end) on stack |
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*/ |
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static void restore_regs(struct bpf_jit *jit, u32 rs, u32 re, u32 stack_depth) |
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{ |
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u32 off = STK_OFF_R6 + (rs - 6) * 8; |
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if (jit->seen & SEEN_STACK) |
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off += STK_OFF + stack_depth; |
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if (rs == re) |
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/* lg %rs,off(%r15) */ |
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_EMIT6(0xe300f000 | rs << 20 | off, 0x0004); |
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else |
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/* lmg %rs,%re,off(%r15) */ |
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_EMIT6_DISP(0xeb00f000 | rs << 20 | re << 16, 0x0004, off); |
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} |
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/* |
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* Return first seen register (from start) |
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*/ |
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static int get_start(struct bpf_jit *jit, int start) |
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{ |
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int i; |
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for (i = start; i <= 15; i++) { |
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if (jit->seen_reg[i]) |
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return i; |
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} |
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return 0; |
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} |
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/* |
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* Return last seen register (from start) (gap >= 2) |
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*/ |
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static int get_end(struct bpf_jit *jit, int start) |
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{ |
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int i; |
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for (i = start; i < 15; i++) { |
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if (!jit->seen_reg[i] && !jit->seen_reg[i + 1]) |
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return i - 1; |
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} |
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return jit->seen_reg[15] ? 15 : 14; |
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} |
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#define REGS_SAVE 1 |
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#define REGS_RESTORE 0 |
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/* |
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* Save and restore clobbered registers (6-15) on stack. |
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* We save/restore registers in chunks with gap >= 2 registers. |
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*/ |
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static void save_restore_regs(struct bpf_jit *jit, int op, u32 stack_depth) |
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{ |
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const int last = 15, save_restore_size = 6; |
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int re = 6, rs; |
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if (is_first_pass(jit)) { |
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/* |
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* We don't know yet which registers are used. Reserve space |
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* conservatively. |
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*/ |
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jit->prg += (last - re + 1) * save_restore_size; |
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return; |
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} |
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do { |
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rs = get_start(jit, re); |
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if (!rs) |
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break; |
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re = get_end(jit, rs + 1); |
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if (op == REGS_SAVE) |
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save_regs(jit, rs, re); |
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else |
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restore_regs(jit, rs, re, stack_depth); |
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re++; |
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} while (re <= last); |
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} |
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static void bpf_skip(struct bpf_jit *jit, int size) |
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{ |
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if (size >= 6 && !is_valid_rel(size)) { |
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/* brcl 0xf,size */ |
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EMIT6_PCREL_RIL(0xc0f4000000, size); |
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size -= 6; |
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} else if (size >= 4 && is_valid_rel(size)) { |
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/* brc 0xf,size */ |
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EMIT4_PCREL(0xa7f40000, size); |
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size -= 4; |
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} |
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while (size >= 2) { |
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/* bcr 0,%0 */ |
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_EMIT2(0x0700); |
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size -= 2; |
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} |
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} |
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|
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/* |
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* Emit function prologue |
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* |
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* Save registers and create stack frame if necessary. |
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* See stack frame layout desription in "bpf_jit.h"! |
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*/ |
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static void bpf_jit_prologue(struct bpf_jit *jit, u32 stack_depth) |
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{ |
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if (jit->seen & SEEN_TAIL_CALL) { |
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/* xc STK_OFF_TCCNT(4,%r15),STK_OFF_TCCNT(%r15) */ |
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_EMIT6(0xd703f000 | STK_OFF_TCCNT, 0xf000 | STK_OFF_TCCNT); |
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} else { |
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/* |
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* There are no tail calls. Insert nops in order to have |
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* tail_call_start at a predictable offset. |
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*/ |
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bpf_skip(jit, 6); |
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} |
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/* Tail calls have to skip above initialization */ |
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jit->tail_call_start = jit->prg; |
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/* Save registers */ |
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save_restore_regs(jit, REGS_SAVE, stack_depth); |
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/* Setup literal pool */ |
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if (is_first_pass(jit) || (jit->seen & SEEN_LITERAL)) { |
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if (!is_first_pass(jit) && |
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is_valid_ldisp(jit->size - (jit->prg + 2))) { |
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/* basr %l,0 */ |
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EMIT2(0x0d00, REG_L, REG_0); |
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jit->base_ip = jit->prg; |
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} else { |
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/* larl %l,lit32_start */ |
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EMIT6_PCREL_RILB(0xc0000000, REG_L, jit->lit32_start); |
|
jit->base_ip = jit->lit32_start; |
|
} |
|
} |
|
/* Setup stack and backchain */ |
|
if (is_first_pass(jit) || (jit->seen & SEEN_STACK)) { |
|
if (is_first_pass(jit) || (jit->seen & SEEN_FUNC)) |
|
/* lgr %w1,%r15 (backchain) */ |
|
EMIT4(0xb9040000, REG_W1, REG_15); |
|
/* la %bfp,STK_160_UNUSED(%r15) (BPF frame pointer) */ |
|
EMIT4_DISP(0x41000000, BPF_REG_FP, REG_15, STK_160_UNUSED); |
|
/* aghi %r15,-STK_OFF */ |
|
EMIT4_IMM(0xa70b0000, REG_15, -(STK_OFF + stack_depth)); |
|
if (is_first_pass(jit) || (jit->seen & SEEN_FUNC)) |
|
/* stg %w1,152(%r15) (backchain) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W1, REG_0, |
|
REG_15, 152); |
|
} |
|
} |
|
|
|
/* |
|
* Function epilogue |
|
*/ |
|
static void bpf_jit_epilogue(struct bpf_jit *jit, u32 stack_depth) |
|
{ |
|
jit->exit_ip = jit->prg; |
|
/* Load exit code: lgr %r2,%b0 */ |
|
EMIT4(0xb9040000, REG_2, BPF_REG_0); |
|
/* Restore registers */ |
|
save_restore_regs(jit, REGS_RESTORE, stack_depth); |
|
if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable) { |
|
jit->r14_thunk_ip = jit->prg; |
|
/* Generate __s390_indirect_jump_r14 thunk */ |
|
if (test_facility(35)) { |
|
/* exrl %r0,.+10 */ |
|
EMIT6_PCREL_RIL(0xc6000000, jit->prg + 10); |
|
} else { |
|
/* larl %r1,.+14 */ |
|
EMIT6_PCREL_RILB(0xc0000000, REG_1, jit->prg + 14); |
|
/* ex 0,0(%r1) */ |
|
EMIT4_DISP(0x44000000, REG_0, REG_1, 0); |
|
} |
|
/* j . */ |
|
EMIT4_PCREL(0xa7f40000, 0); |
|
} |
|
/* br %r14 */ |
|
_EMIT2(0x07fe); |
|
|
|
if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable && |
|
(is_first_pass(jit) || (jit->seen & SEEN_FUNC))) { |
|
jit->r1_thunk_ip = jit->prg; |
|
/* Generate __s390_indirect_jump_r1 thunk */ |
|
if (test_facility(35)) { |
|
/* exrl %r0,.+10 */ |
|
EMIT6_PCREL_RIL(0xc6000000, jit->prg + 10); |
|
/* j . */ |
|
EMIT4_PCREL(0xa7f40000, 0); |
|
/* br %r1 */ |
|
_EMIT2(0x07f1); |
|
} else { |
|
/* ex 0,S390_lowcore.br_r1_tampoline */ |
|
EMIT4_DISP(0x44000000, REG_0, REG_0, |
|
offsetof(struct lowcore, br_r1_trampoline)); |
|
/* j . */ |
|
EMIT4_PCREL(0xa7f40000, 0); |
|
} |
|
} |
|
} |
|
|
|
static int get_probe_mem_regno(const u8 *insn) |
|
{ |
|
/* |
|
* insn must point to llgc, llgh, llgf or lg, which have destination |
|
* register at the same position. |
|
*/ |
|
if (insn[0] != 0xe3) /* common llgc, llgh, llgf and lg prefix */ |
|
return -1; |
|
if (insn[5] != 0x90 && /* llgc */ |
|
insn[5] != 0x91 && /* llgh */ |
|
insn[5] != 0x16 && /* llgf */ |
|
insn[5] != 0x04) /* lg */ |
|
return -1; |
|
return insn[1] >> 4; |
|
} |
|
|
|
static bool ex_handler_bpf(const struct exception_table_entry *x, |
|
struct pt_regs *regs) |
|
{ |
|
int regno; |
|
u8 *insn; |
|
|
|
regs->psw.addr = extable_fixup(x); |
|
insn = (u8 *)__rewind_psw(regs->psw, regs->int_code >> 16); |
|
regno = get_probe_mem_regno(insn); |
|
if (WARN_ON_ONCE(regno < 0)) |
|
/* JIT bug - unexpected instruction. */ |
|
return false; |
|
regs->gprs[regno] = 0; |
|
return true; |
|
} |
|
|
|
static int bpf_jit_probe_mem(struct bpf_jit *jit, struct bpf_prog *fp, |
|
int probe_prg, int nop_prg) |
|
{ |
|
struct exception_table_entry *ex; |
|
s64 delta; |
|
u8 *insn; |
|
int prg; |
|
int i; |
|
|
|
if (!fp->aux->extable) |
|
/* Do nothing during early JIT passes. */ |
|
return 0; |
|
insn = jit->prg_buf + probe_prg; |
|
if (WARN_ON_ONCE(get_probe_mem_regno(insn) < 0)) |
|
/* JIT bug - unexpected probe instruction. */ |
|
return -1; |
|
if (WARN_ON_ONCE(probe_prg + insn_length(*insn) != nop_prg)) |
|
/* JIT bug - gap between probe and nop instructions. */ |
|
return -1; |
|
for (i = 0; i < 2; i++) { |
|
if (WARN_ON_ONCE(jit->excnt >= fp->aux->num_exentries)) |
|
/* Verifier bug - not enough entries. */ |
|
return -1; |
|
ex = &fp->aux->extable[jit->excnt]; |
|
/* Add extable entries for probe and nop instructions. */ |
|
prg = i == 0 ? probe_prg : nop_prg; |
|
delta = jit->prg_buf + prg - (u8 *)&ex->insn; |
|
if (WARN_ON_ONCE(delta < INT_MIN || delta > INT_MAX)) |
|
/* JIT bug - code and extable must be close. */ |
|
return -1; |
|
ex->insn = delta; |
|
/* |
|
* Always land on the nop. Note that extable infrastructure |
|
* ignores fixup field, it is handled by ex_handler_bpf(). |
|
*/ |
|
delta = jit->prg_buf + nop_prg - (u8 *)&ex->fixup; |
|
if (WARN_ON_ONCE(delta < INT_MIN || delta > INT_MAX)) |
|
/* JIT bug - landing pad and extable must be close. */ |
|
return -1; |
|
ex->fixup = delta; |
|
ex->handler = (u8 *)ex_handler_bpf - (u8 *)&ex->handler; |
|
jit->excnt++; |
|
} |
|
return 0; |
|
} |
|
|
|
/* |
|
* Compile one eBPF instruction into s390x code |
|
* |
|
* NOTE: Use noinline because for gcov (-fprofile-arcs) gcc allocates a lot of |
|
* stack space for the large switch statement. |
|
*/ |
|
static noinline int bpf_jit_insn(struct bpf_jit *jit, struct bpf_prog *fp, |
|
int i, bool extra_pass, u32 stack_depth) |
|
{ |
|
struct bpf_insn *insn = &fp->insnsi[i]; |
|
u32 dst_reg = insn->dst_reg; |
|
u32 src_reg = insn->src_reg; |
|
int last, insn_count = 1; |
|
u32 *addrs = jit->addrs; |
|
s32 imm = insn->imm; |
|
s16 off = insn->off; |
|
int probe_prg = -1; |
|
unsigned int mask; |
|
int nop_prg; |
|
int err; |
|
|
|
if (BPF_CLASS(insn->code) == BPF_LDX && |
|
BPF_MODE(insn->code) == BPF_PROBE_MEM) |
|
probe_prg = jit->prg; |
|
|
|
switch (insn->code) { |
|
/* |
|
* BPF_MOV |
|
*/ |
|
case BPF_ALU | BPF_MOV | BPF_X: /* dst = (u32) src */ |
|
/* llgfr %dst,%src */ |
|
EMIT4(0xb9160000, dst_reg, src_reg); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */ |
|
/* lgr %dst,%src */ |
|
EMIT4(0xb9040000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_MOV | BPF_K: /* dst = (u32) imm */ |
|
/* llilf %dst,imm */ |
|
EMIT6_IMM(0xc00f0000, dst_reg, imm); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = imm */ |
|
/* lgfi %dst,imm */ |
|
EMIT6_IMM(0xc0010000, dst_reg, imm); |
|
break; |
|
/* |
|
* BPF_LD 64 |
|
*/ |
|
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */ |
|
{ |
|
/* 16 byte instruction that uses two 'struct bpf_insn' */ |
|
u64 imm64; |
|
|
|
imm64 = (u64)(u32) insn[0].imm | ((u64)(u32) insn[1].imm) << 32; |
|
/* lgrl %dst,imm */ |
|
EMIT6_PCREL_RILB(0xc4080000, dst_reg, _EMIT_CONST_U64(imm64)); |
|
insn_count = 2; |
|
break; |
|
} |
|
/* |
|
* BPF_ADD |
|
*/ |
|
case BPF_ALU | BPF_ADD | BPF_X: /* dst = (u32) dst + (u32) src */ |
|
/* ar %dst,%src */ |
|
EMIT2(0x1a00, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_ADD | BPF_X: /* dst = dst + src */ |
|
/* agr %dst,%src */ |
|
EMIT4(0xb9080000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_ADD | BPF_K: /* dst = (u32) dst + (u32) imm */ |
|
if (!imm) |
|
break; |
|
/* alfi %dst,imm */ |
|
EMIT6_IMM(0xc20b0000, dst_reg, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_ADD | BPF_K: /* dst = dst + imm */ |
|
if (!imm) |
|
break; |
|
/* agfi %dst,imm */ |
|
EMIT6_IMM(0xc2080000, dst_reg, imm); |
|
break; |
|
/* |
|
* BPF_SUB |
|
*/ |
|
case BPF_ALU | BPF_SUB | BPF_X: /* dst = (u32) dst - (u32) src */ |
|
/* sr %dst,%src */ |
|
EMIT2(0x1b00, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_SUB | BPF_X: /* dst = dst - src */ |
|
/* sgr %dst,%src */ |
|
EMIT4(0xb9090000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_SUB | BPF_K: /* dst = (u32) dst - (u32) imm */ |
|
if (!imm) |
|
break; |
|
/* alfi %dst,-imm */ |
|
EMIT6_IMM(0xc20b0000, dst_reg, -imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_SUB | BPF_K: /* dst = dst - imm */ |
|
if (!imm) |
|
break; |
|
/* agfi %dst,-imm */ |
|
EMIT6_IMM(0xc2080000, dst_reg, -imm); |
|
break; |
|
/* |
|
* BPF_MUL |
|
*/ |
|
case BPF_ALU | BPF_MUL | BPF_X: /* dst = (u32) dst * (u32) src */ |
|
/* msr %dst,%src */ |
|
EMIT4(0xb2520000, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_MUL | BPF_X: /* dst = dst * src */ |
|
/* msgr %dst,%src */ |
|
EMIT4(0xb90c0000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_MUL | BPF_K: /* dst = (u32) dst * (u32) imm */ |
|
if (imm == 1) |
|
break; |
|
/* msfi %r5,imm */ |
|
EMIT6_IMM(0xc2010000, dst_reg, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_MUL | BPF_K: /* dst = dst * imm */ |
|
if (imm == 1) |
|
break; |
|
/* msgfi %dst,imm */ |
|
EMIT6_IMM(0xc2000000, dst_reg, imm); |
|
break; |
|
/* |
|
* BPF_DIV / BPF_MOD |
|
*/ |
|
case BPF_ALU | BPF_DIV | BPF_X: /* dst = (u32) dst / (u32) src */ |
|
case BPF_ALU | BPF_MOD | BPF_X: /* dst = (u32) dst % (u32) src */ |
|
{ |
|
int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
|
|
|
/* lhi %w0,0 */ |
|
EMIT4_IMM(0xa7080000, REG_W0, 0); |
|
/* lr %w1,%dst */ |
|
EMIT2(0x1800, REG_W1, dst_reg); |
|
/* dlr %w0,%src */ |
|
EMIT4(0xb9970000, REG_W0, src_reg); |
|
/* llgfr %dst,%rc */ |
|
EMIT4(0xb9160000, dst_reg, rc_reg); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
} |
|
case BPF_ALU64 | BPF_DIV | BPF_X: /* dst = dst / src */ |
|
case BPF_ALU64 | BPF_MOD | BPF_X: /* dst = dst % src */ |
|
{ |
|
int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
|
|
|
/* lghi %w0,0 */ |
|
EMIT4_IMM(0xa7090000, REG_W0, 0); |
|
/* lgr %w1,%dst */ |
|
EMIT4(0xb9040000, REG_W1, dst_reg); |
|
/* dlgr %w0,%dst */ |
|
EMIT4(0xb9870000, REG_W0, src_reg); |
|
/* lgr %dst,%rc */ |
|
EMIT4(0xb9040000, dst_reg, rc_reg); |
|
break; |
|
} |
|
case BPF_ALU | BPF_DIV | BPF_K: /* dst = (u32) dst / (u32) imm */ |
|
case BPF_ALU | BPF_MOD | BPF_K: /* dst = (u32) dst % (u32) imm */ |
|
{ |
|
int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
|
|
|
if (imm == 1) { |
|
if (BPF_OP(insn->code) == BPF_MOD) |
|
/* lhgi %dst,0 */ |
|
EMIT4_IMM(0xa7090000, dst_reg, 0); |
|
break; |
|
} |
|
/* lhi %w0,0 */ |
|
EMIT4_IMM(0xa7080000, REG_W0, 0); |
|
/* lr %w1,%dst */ |
|
EMIT2(0x1800, REG_W1, dst_reg); |
|
if (!is_first_pass(jit) && can_use_ldisp_for_lit32(jit)) { |
|
/* dl %w0,<d(imm)>(%l) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0097, REG_W0, REG_0, REG_L, |
|
EMIT_CONST_U32(imm)); |
|
} else { |
|
/* lgfrl %dst,imm */ |
|
EMIT6_PCREL_RILB(0xc40c0000, dst_reg, |
|
_EMIT_CONST_U32(imm)); |
|
jit->seen |= SEEN_LITERAL; |
|
/* dlr %w0,%dst */ |
|
EMIT4(0xb9970000, REG_W0, dst_reg); |
|
} |
|
/* llgfr %dst,%rc */ |
|
EMIT4(0xb9160000, dst_reg, rc_reg); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
} |
|
case BPF_ALU64 | BPF_DIV | BPF_K: /* dst = dst / imm */ |
|
case BPF_ALU64 | BPF_MOD | BPF_K: /* dst = dst % imm */ |
|
{ |
|
int rc_reg = BPF_OP(insn->code) == BPF_DIV ? REG_W1 : REG_W0; |
|
|
|
if (imm == 1) { |
|
if (BPF_OP(insn->code) == BPF_MOD) |
|
/* lhgi %dst,0 */ |
|
EMIT4_IMM(0xa7090000, dst_reg, 0); |
|
break; |
|
} |
|
/* lghi %w0,0 */ |
|
EMIT4_IMM(0xa7090000, REG_W0, 0); |
|
/* lgr %w1,%dst */ |
|
EMIT4(0xb9040000, REG_W1, dst_reg); |
|
if (!is_first_pass(jit) && can_use_ldisp_for_lit64(jit)) { |
|
/* dlg %w0,<d(imm)>(%l) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0087, REG_W0, REG_0, REG_L, |
|
EMIT_CONST_U64(imm)); |
|
} else { |
|
/* lgrl %dst,imm */ |
|
EMIT6_PCREL_RILB(0xc4080000, dst_reg, |
|
_EMIT_CONST_U64(imm)); |
|
jit->seen |= SEEN_LITERAL; |
|
/* dlgr %w0,%dst */ |
|
EMIT4(0xb9870000, REG_W0, dst_reg); |
|
} |
|
/* lgr %dst,%rc */ |
|
EMIT4(0xb9040000, dst_reg, rc_reg); |
|
break; |
|
} |
|
/* |
|
* BPF_AND |
|
*/ |
|
case BPF_ALU | BPF_AND | BPF_X: /* dst = (u32) dst & (u32) src */ |
|
/* nr %dst,%src */ |
|
EMIT2(0x1400, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */ |
|
/* ngr %dst,%src */ |
|
EMIT4(0xb9800000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_AND | BPF_K: /* dst = (u32) dst & (u32) imm */ |
|
/* nilf %dst,imm */ |
|
EMIT6_IMM(0xc00b0000, dst_reg, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */ |
|
if (!is_first_pass(jit) && can_use_ldisp_for_lit64(jit)) { |
|
/* ng %dst,<d(imm)>(%l) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0080, |
|
dst_reg, REG_0, REG_L, |
|
EMIT_CONST_U64(imm)); |
|
} else { |
|
/* lgrl %w0,imm */ |
|
EMIT6_PCREL_RILB(0xc4080000, REG_W0, |
|
_EMIT_CONST_U64(imm)); |
|
jit->seen |= SEEN_LITERAL; |
|
/* ngr %dst,%w0 */ |
|
EMIT4(0xb9800000, dst_reg, REG_W0); |
|
} |
|
break; |
|
/* |
|
* BPF_OR |
|
*/ |
|
case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */ |
|
/* or %dst,%src */ |
|
EMIT2(0x1600, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */ |
|
/* ogr %dst,%src */ |
|
EMIT4(0xb9810000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_OR | BPF_K: /* dst = (u32) dst | (u32) imm */ |
|
/* oilf %dst,imm */ |
|
EMIT6_IMM(0xc00d0000, dst_reg, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_OR | BPF_K: /* dst = dst | imm */ |
|
if (!is_first_pass(jit) && can_use_ldisp_for_lit64(jit)) { |
|
/* og %dst,<d(imm)>(%l) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0081, |
|
dst_reg, REG_0, REG_L, |
|
EMIT_CONST_U64(imm)); |
|
} else { |
|
/* lgrl %w0,imm */ |
|
EMIT6_PCREL_RILB(0xc4080000, REG_W0, |
|
_EMIT_CONST_U64(imm)); |
|
jit->seen |= SEEN_LITERAL; |
|
/* ogr %dst,%w0 */ |
|
EMIT4(0xb9810000, dst_reg, REG_W0); |
|
} |
|
break; |
|
/* |
|
* BPF_XOR |
|
*/ |
|
case BPF_ALU | BPF_XOR | BPF_X: /* dst = (u32) dst ^ (u32) src */ |
|
/* xr %dst,%src */ |
|
EMIT2(0x1700, dst_reg, src_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_XOR | BPF_X: /* dst = dst ^ src */ |
|
/* xgr %dst,%src */ |
|
EMIT4(0xb9820000, dst_reg, src_reg); |
|
break; |
|
case BPF_ALU | BPF_XOR | BPF_K: /* dst = (u32) dst ^ (u32) imm */ |
|
if (!imm) |
|
break; |
|
/* xilf %dst,imm */ |
|
EMIT6_IMM(0xc0070000, dst_reg, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_XOR | BPF_K: /* dst = dst ^ imm */ |
|
if (!is_first_pass(jit) && can_use_ldisp_for_lit64(jit)) { |
|
/* xg %dst,<d(imm)>(%l) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0082, |
|
dst_reg, REG_0, REG_L, |
|
EMIT_CONST_U64(imm)); |
|
} else { |
|
/* lgrl %w0,imm */ |
|
EMIT6_PCREL_RILB(0xc4080000, REG_W0, |
|
_EMIT_CONST_U64(imm)); |
|
jit->seen |= SEEN_LITERAL; |
|
/* xgr %dst,%w0 */ |
|
EMIT4(0xb9820000, dst_reg, REG_W0); |
|
} |
|
break; |
|
/* |
|
* BPF_LSH |
|
*/ |
|
case BPF_ALU | BPF_LSH | BPF_X: /* dst = (u32) dst << (u32) src */ |
|
/* sll %dst,0(%src) */ |
|
EMIT4_DISP(0x89000000, dst_reg, src_reg, 0); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_LSH | BPF_X: /* dst = dst << src */ |
|
/* sllg %dst,%dst,0(%src) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, src_reg, 0); |
|
break; |
|
case BPF_ALU | BPF_LSH | BPF_K: /* dst = (u32) dst << (u32) imm */ |
|
if (imm == 0) |
|
break; |
|
/* sll %dst,imm(%r0) */ |
|
EMIT4_DISP(0x89000000, dst_reg, REG_0, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_LSH | BPF_K: /* dst = dst << imm */ |
|
if (imm == 0) |
|
break; |
|
/* sllg %dst,%dst,imm(%r0) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, REG_0, imm); |
|
break; |
|
/* |
|
* BPF_RSH |
|
*/ |
|
case BPF_ALU | BPF_RSH | BPF_X: /* dst = (u32) dst >> (u32) src */ |
|
/* srl %dst,0(%src) */ |
|
EMIT4_DISP(0x88000000, dst_reg, src_reg, 0); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_RSH | BPF_X: /* dst = dst >> src */ |
|
/* srlg %dst,%dst,0(%src) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, src_reg, 0); |
|
break; |
|
case BPF_ALU | BPF_RSH | BPF_K: /* dst = (u32) dst >> (u32) imm */ |
|
if (imm == 0) |
|
break; |
|
/* srl %dst,imm(%r0) */ |
|
EMIT4_DISP(0x88000000, dst_reg, REG_0, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_RSH | BPF_K: /* dst = dst >> imm */ |
|
if (imm == 0) |
|
break; |
|
/* srlg %dst,%dst,imm(%r0) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, REG_0, imm); |
|
break; |
|
/* |
|
* BPF_ARSH |
|
*/ |
|
case BPF_ALU | BPF_ARSH | BPF_X: /* ((s32) dst) >>= src */ |
|
/* sra %dst,%dst,0(%src) */ |
|
EMIT4_DISP(0x8a000000, dst_reg, src_reg, 0); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_ARSH | BPF_X: /* ((s64) dst) >>= src */ |
|
/* srag %dst,%dst,0(%src) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, src_reg, 0); |
|
break; |
|
case BPF_ALU | BPF_ARSH | BPF_K: /* ((s32) dst >> imm */ |
|
if (imm == 0) |
|
break; |
|
/* sra %dst,imm(%r0) */ |
|
EMIT4_DISP(0x8a000000, dst_reg, REG_0, imm); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_ARSH | BPF_K: /* ((s64) dst) >>= imm */ |
|
if (imm == 0) |
|
break; |
|
/* srag %dst,%dst,imm(%r0) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000a, dst_reg, dst_reg, REG_0, imm); |
|
break; |
|
/* |
|
* BPF_NEG |
|
*/ |
|
case BPF_ALU | BPF_NEG: /* dst = (u32) -dst */ |
|
/* lcr %dst,%dst */ |
|
EMIT2(0x1300, dst_reg, dst_reg); |
|
EMIT_ZERO(dst_reg); |
|
break; |
|
case BPF_ALU64 | BPF_NEG: /* dst = -dst */ |
|
/* lcgr %dst,%dst */ |
|
EMIT4(0xb9030000, dst_reg, dst_reg); |
|
break; |
|
/* |
|
* BPF_FROM_BE/LE |
|
*/ |
|
case BPF_ALU | BPF_END | BPF_FROM_BE: |
|
/* s390 is big endian, therefore only clear high order bytes */ |
|
switch (imm) { |
|
case 16: /* dst = (u16) cpu_to_be16(dst) */ |
|
/* llghr %dst,%dst */ |
|
EMIT4(0xb9850000, dst_reg, dst_reg); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case 32: /* dst = (u32) cpu_to_be32(dst) */ |
|
if (!fp->aux->verifier_zext) |
|
/* llgfr %dst,%dst */ |
|
EMIT4(0xb9160000, dst_reg, dst_reg); |
|
break; |
|
case 64: /* dst = (u64) cpu_to_be64(dst) */ |
|
break; |
|
} |
|
break; |
|
case BPF_ALU | BPF_END | BPF_FROM_LE: |
|
switch (imm) { |
|
case 16: /* dst = (u16) cpu_to_le16(dst) */ |
|
/* lrvr %dst,%dst */ |
|
EMIT4(0xb91f0000, dst_reg, dst_reg); |
|
/* srl %dst,16(%r0) */ |
|
EMIT4_DISP(0x88000000, dst_reg, REG_0, 16); |
|
/* llghr %dst,%dst */ |
|
EMIT4(0xb9850000, dst_reg, dst_reg); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case 32: /* dst = (u32) cpu_to_le32(dst) */ |
|
/* lrvr %dst,%dst */ |
|
EMIT4(0xb91f0000, dst_reg, dst_reg); |
|
if (!fp->aux->verifier_zext) |
|
/* llgfr %dst,%dst */ |
|
EMIT4(0xb9160000, dst_reg, dst_reg); |
|
break; |
|
case 64: /* dst = (u64) cpu_to_le64(dst) */ |
|
/* lrvgr %dst,%dst */ |
|
EMIT4(0xb90f0000, dst_reg, dst_reg); |
|
break; |
|
} |
|
break; |
|
/* |
|
* BPF_ST(X) |
|
*/ |
|
case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src_reg */ |
|
/* stcy %src,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0072, src_reg, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */ |
|
/* sthy %src,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0070, src_reg, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */ |
|
/* sty %src,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0050, src_reg, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */ |
|
/* stg %src,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0024, src_reg, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */ |
|
/* lhi %w0,imm */ |
|
EMIT4_IMM(0xa7080000, REG_W0, (u8) imm); |
|
/* stcy %w0,off(dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0072, REG_W0, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */ |
|
/* lhi %w0,imm */ |
|
EMIT4_IMM(0xa7080000, REG_W0, (u16) imm); |
|
/* sthy %w0,off(dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0070, REG_W0, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */ |
|
/* llilf %w0,imm */ |
|
EMIT6_IMM(0xc00f0000, REG_W0, (u32) imm); |
|
/* sty %w0,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0050, REG_W0, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */ |
|
/* lgfi %w0,imm */ |
|
EMIT6_IMM(0xc0010000, REG_W0, imm); |
|
/* stg %w0,off(%dst) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0024, REG_W0, dst_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
/* |
|
* BPF_ATOMIC |
|
*/ |
|
case BPF_STX | BPF_ATOMIC | BPF_DW: |
|
case BPF_STX | BPF_ATOMIC | BPF_W: |
|
if (insn->imm != BPF_ADD) { |
|
pr_err("Unknown atomic operation %02x\n", insn->imm); |
|
return -1; |
|
} |
|
|
|
/* *(u32/u64 *)(dst + off) += src |
|
* |
|
* BFW_W: laal %w0,%src,off(%dst) |
|
* BPF_DW: laalg %w0,%src,off(%dst) |
|
*/ |
|
EMIT6_DISP_LH(0xeb000000, |
|
BPF_SIZE(insn->code) == BPF_W ? 0x00fa : 0x00ea, |
|
REG_W0, src_reg, dst_reg, off); |
|
jit->seen |= SEEN_MEM; |
|
break; |
|
/* |
|
* BPF_LDX |
|
*/ |
|
case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */ |
|
case BPF_LDX | BPF_PROBE_MEM | BPF_B: |
|
/* llgc %dst,0(off,%src) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0090, dst_reg, src_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */ |
|
case BPF_LDX | BPF_PROBE_MEM | BPF_H: |
|
/* llgh %dst,0(off,%src) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0091, dst_reg, src_reg, REG_0, off); |
|
jit->seen |= SEEN_MEM; |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */ |
|
case BPF_LDX | BPF_PROBE_MEM | BPF_W: |
|
/* llgf %dst,off(%src) */ |
|
jit->seen |= SEEN_MEM; |
|
EMIT6_DISP_LH(0xe3000000, 0x0016, dst_reg, src_reg, REG_0, off); |
|
if (insn_is_zext(&insn[1])) |
|
insn_count = 2; |
|
break; |
|
case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */ |
|
case BPF_LDX | BPF_PROBE_MEM | BPF_DW: |
|
/* lg %dst,0(off,%src) */ |
|
jit->seen |= SEEN_MEM; |
|
EMIT6_DISP_LH(0xe3000000, 0x0004, dst_reg, src_reg, REG_0, off); |
|
break; |
|
/* |
|
* BPF_JMP / CALL |
|
*/ |
|
case BPF_JMP | BPF_CALL: |
|
{ |
|
u64 func; |
|
bool func_addr_fixed; |
|
int ret; |
|
|
|
ret = bpf_jit_get_func_addr(fp, insn, extra_pass, |
|
&func, &func_addr_fixed); |
|
if (ret < 0) |
|
return -1; |
|
|
|
REG_SET_SEEN(BPF_REG_5); |
|
jit->seen |= SEEN_FUNC; |
|
/* lgrl %w1,func */ |
|
EMIT6_PCREL_RILB(0xc4080000, REG_W1, _EMIT_CONST_U64(func)); |
|
if (__is_defined(CC_USING_EXPOLINE) && !nospec_disable) { |
|
/* brasl %r14,__s390_indirect_jump_r1 */ |
|
EMIT6_PCREL_RILB(0xc0050000, REG_14, jit->r1_thunk_ip); |
|
} else { |
|
/* basr %r14,%w1 */ |
|
EMIT2(0x0d00, REG_14, REG_W1); |
|
} |
|
/* lgr %b0,%r2: load return value into %b0 */ |
|
EMIT4(0xb9040000, BPF_REG_0, REG_2); |
|
break; |
|
} |
|
case BPF_JMP | BPF_TAIL_CALL: { |
|
int patch_1_clrj, patch_2_clij, patch_3_brc; |
|
|
|
/* |
|
* Implicit input: |
|
* B1: pointer to ctx |
|
* B2: pointer to bpf_array |
|
* B3: index in bpf_array |
|
*/ |
|
jit->seen |= SEEN_TAIL_CALL; |
|
|
|
/* |
|
* if (index >= array->map.max_entries) |
|
* goto out; |
|
*/ |
|
|
|
/* llgf %w1,map.max_entries(%b2) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0016, REG_W1, REG_0, BPF_REG_2, |
|
offsetof(struct bpf_array, map.max_entries)); |
|
/* if ((u32)%b3 >= (u32)%w1) goto out; */ |
|
/* clrj %b3,%w1,0xa,out */ |
|
patch_1_clrj = jit->prg; |
|
EMIT6_PCREL_RIEB(0xec000000, 0x0077, BPF_REG_3, REG_W1, 0xa, |
|
jit->prg); |
|
|
|
/* |
|
* if (tail_call_cnt++ > MAX_TAIL_CALL_CNT) |
|
* goto out; |
|
*/ |
|
|
|
if (jit->seen & SEEN_STACK) |
|
off = STK_OFF_TCCNT + STK_OFF + stack_depth; |
|
else |
|
off = STK_OFF_TCCNT; |
|
/* lhi %w0,1 */ |
|
EMIT4_IMM(0xa7080000, REG_W0, 1); |
|
/* laal %w1,%w0,off(%r15) */ |
|
EMIT6_DISP_LH(0xeb000000, 0x00fa, REG_W1, REG_W0, REG_15, off); |
|
/* clij %w1,MAX_TAIL_CALL_CNT,0x2,out */ |
|
patch_2_clij = jit->prg; |
|
EMIT6_PCREL_RIEC(0xec000000, 0x007f, REG_W1, MAX_TAIL_CALL_CNT, |
|
2, jit->prg); |
|
|
|
/* |
|
* prog = array->ptrs[index]; |
|
* if (prog == NULL) |
|
* goto out; |
|
*/ |
|
|
|
/* llgfr %r1,%b3: %r1 = (u32) index */ |
|
EMIT4(0xb9160000, REG_1, BPF_REG_3); |
|
/* sllg %r1,%r1,3: %r1 *= 8 */ |
|
EMIT6_DISP_LH(0xeb000000, 0x000d, REG_1, REG_1, REG_0, 3); |
|
/* ltg %r1,prog(%b2,%r1) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0002, REG_1, BPF_REG_2, |
|
REG_1, offsetof(struct bpf_array, ptrs)); |
|
/* brc 0x8,out */ |
|
patch_3_brc = jit->prg; |
|
EMIT4_PCREL_RIC(0xa7040000, 8, jit->prg); |
|
|
|
/* |
|
* Restore registers before calling function |
|
*/ |
|
save_restore_regs(jit, REGS_RESTORE, stack_depth); |
|
|
|
/* |
|
* goto *(prog->bpf_func + tail_call_start); |
|
*/ |
|
|
|
/* lg %r1,bpf_func(%r1) */ |
|
EMIT6_DISP_LH(0xe3000000, 0x0004, REG_1, REG_1, REG_0, |
|
offsetof(struct bpf_prog, bpf_func)); |
|
/* bc 0xf,tail_call_start(%r1) */ |
|
_EMIT4(0x47f01000 + jit->tail_call_start); |
|
/* out: */ |
|
if (jit->prg_buf) { |
|
*(u16 *)(jit->prg_buf + patch_1_clrj + 2) = |
|
(jit->prg - patch_1_clrj) >> 1; |
|
*(u16 *)(jit->prg_buf + patch_2_clij + 2) = |
|
(jit->prg - patch_2_clij) >> 1; |
|
*(u16 *)(jit->prg_buf + patch_3_brc + 2) = |
|
(jit->prg - patch_3_brc) >> 1; |
|
} |
|
break; |
|
} |
|
case BPF_JMP | BPF_EXIT: /* return b0 */ |
|
last = (i == fp->len - 1) ? 1 : 0; |
|
if (last) |
|
break; |
|
if (!is_first_pass(jit) && can_use_rel(jit, jit->exit_ip)) |
|
/* brc 0xf, <exit> */ |
|
EMIT4_PCREL_RIC(0xa7040000, 0xf, jit->exit_ip); |
|
else |
|
/* brcl 0xf, <exit> */ |
|
EMIT6_PCREL_RILC(0xc0040000, 0xf, jit->exit_ip); |
|
break; |
|
/* |
|
* Branch relative (number of skipped instructions) to offset on |
|
* condition. |
|
* |
|
* Condition code to mask mapping: |
|
* |
|
* CC | Description | Mask |
|
* ------------------------------ |
|
* 0 | Operands equal | 8 |
|
* 1 | First operand low | 4 |
|
* 2 | First operand high | 2 |
|
* 3 | Unused | 1 |
|
* |
|
* For s390x relative branches: ip = ip + off_bytes |
|
* For BPF relative branches: insn = insn + off_insns + 1 |
|
* |
|
* For example for s390x with offset 0 we jump to the branch |
|
* instruction itself (loop) and for BPF with offset 0 we |
|
* branch to the instruction behind the branch. |
|
*/ |
|
case BPF_JMP | BPF_JA: /* if (true) */ |
|
mask = 0xf000; /* j */ |
|
goto branch_oc; |
|
case BPF_JMP | BPF_JSGT | BPF_K: /* ((s64) dst > (s64) imm) */ |
|
case BPF_JMP32 | BPF_JSGT | BPF_K: /* ((s32) dst > (s32) imm) */ |
|
mask = 0x2000; /* jh */ |
|
goto branch_ks; |
|
case BPF_JMP | BPF_JSLT | BPF_K: /* ((s64) dst < (s64) imm) */ |
|
case BPF_JMP32 | BPF_JSLT | BPF_K: /* ((s32) dst < (s32) imm) */ |
|
mask = 0x4000; /* jl */ |
|
goto branch_ks; |
|
case BPF_JMP | BPF_JSGE | BPF_K: /* ((s64) dst >= (s64) imm) */ |
|
case BPF_JMP32 | BPF_JSGE | BPF_K: /* ((s32) dst >= (s32) imm) */ |
|
mask = 0xa000; /* jhe */ |
|
goto branch_ks; |
|
case BPF_JMP | BPF_JSLE | BPF_K: /* ((s64) dst <= (s64) imm) */ |
|
case BPF_JMP32 | BPF_JSLE | BPF_K: /* ((s32) dst <= (s32) imm) */ |
|
mask = 0xc000; /* jle */ |
|
goto branch_ks; |
|
case BPF_JMP | BPF_JGT | BPF_K: /* (dst_reg > imm) */ |
|
case BPF_JMP32 | BPF_JGT | BPF_K: /* ((u32) dst_reg > (u32) imm) */ |
|
mask = 0x2000; /* jh */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JLT | BPF_K: /* (dst_reg < imm) */ |
|
case BPF_JMP32 | BPF_JLT | BPF_K: /* ((u32) dst_reg < (u32) imm) */ |
|
mask = 0x4000; /* jl */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JGE | BPF_K: /* (dst_reg >= imm) */ |
|
case BPF_JMP32 | BPF_JGE | BPF_K: /* ((u32) dst_reg >= (u32) imm) */ |
|
mask = 0xa000; /* jhe */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JLE | BPF_K: /* (dst_reg <= imm) */ |
|
case BPF_JMP32 | BPF_JLE | BPF_K: /* ((u32) dst_reg <= (u32) imm) */ |
|
mask = 0xc000; /* jle */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JNE | BPF_K: /* (dst_reg != imm) */ |
|
case BPF_JMP32 | BPF_JNE | BPF_K: /* ((u32) dst_reg != (u32) imm) */ |
|
mask = 0x7000; /* jne */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JEQ | BPF_K: /* (dst_reg == imm) */ |
|
case BPF_JMP32 | BPF_JEQ | BPF_K: /* ((u32) dst_reg == (u32) imm) */ |
|
mask = 0x8000; /* je */ |
|
goto branch_ku; |
|
case BPF_JMP | BPF_JSET | BPF_K: /* (dst_reg & imm) */ |
|
case BPF_JMP32 | BPF_JSET | BPF_K: /* ((u32) dst_reg & (u32) imm) */ |
|
mask = 0x7000; /* jnz */ |
|
if (BPF_CLASS(insn->code) == BPF_JMP32) { |
|
/* llilf %w1,imm (load zero extend imm) */ |
|
EMIT6_IMM(0xc00f0000, REG_W1, imm); |
|
/* nr %w1,%dst */ |
|
EMIT2(0x1400, REG_W1, dst_reg); |
|
} else { |
|
/* lgfi %w1,imm (load sign extend imm) */ |
|
EMIT6_IMM(0xc0010000, REG_W1, imm); |
|
/* ngr %w1,%dst */ |
|
EMIT4(0xb9800000, REG_W1, dst_reg); |
|
} |
|
goto branch_oc; |
|
|
|
case BPF_JMP | BPF_JSGT | BPF_X: /* ((s64) dst > (s64) src) */ |
|
case BPF_JMP32 | BPF_JSGT | BPF_X: /* ((s32) dst > (s32) src) */ |
|
mask = 0x2000; /* jh */ |
|
goto branch_xs; |
|
case BPF_JMP | BPF_JSLT | BPF_X: /* ((s64) dst < (s64) src) */ |
|
case BPF_JMP32 | BPF_JSLT | BPF_X: /* ((s32) dst < (s32) src) */ |
|
mask = 0x4000; /* jl */ |
|
goto branch_xs; |
|
case BPF_JMP | BPF_JSGE | BPF_X: /* ((s64) dst >= (s64) src) */ |
|
case BPF_JMP32 | BPF_JSGE | BPF_X: /* ((s32) dst >= (s32) src) */ |
|
mask = 0xa000; /* jhe */ |
|
goto branch_xs; |
|
case BPF_JMP | BPF_JSLE | BPF_X: /* ((s64) dst <= (s64) src) */ |
|
case BPF_JMP32 | BPF_JSLE | BPF_X: /* ((s32) dst <= (s32) src) */ |
|
mask = 0xc000; /* jle */ |
|
goto branch_xs; |
|
case BPF_JMP | BPF_JGT | BPF_X: /* (dst > src) */ |
|
case BPF_JMP32 | BPF_JGT | BPF_X: /* ((u32) dst > (u32) src) */ |
|
mask = 0x2000; /* jh */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JLT | BPF_X: /* (dst < src) */ |
|
case BPF_JMP32 | BPF_JLT | BPF_X: /* ((u32) dst < (u32) src) */ |
|
mask = 0x4000; /* jl */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JGE | BPF_X: /* (dst >= src) */ |
|
case BPF_JMP32 | BPF_JGE | BPF_X: /* ((u32) dst >= (u32) src) */ |
|
mask = 0xa000; /* jhe */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JLE | BPF_X: /* (dst <= src) */ |
|
case BPF_JMP32 | BPF_JLE | BPF_X: /* ((u32) dst <= (u32) src) */ |
|
mask = 0xc000; /* jle */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JNE | BPF_X: /* (dst != src) */ |
|
case BPF_JMP32 | BPF_JNE | BPF_X: /* ((u32) dst != (u32) src) */ |
|
mask = 0x7000; /* jne */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JEQ | BPF_X: /* (dst == src) */ |
|
case BPF_JMP32 | BPF_JEQ | BPF_X: /* ((u32) dst == (u32) src) */ |
|
mask = 0x8000; /* je */ |
|
goto branch_xu; |
|
case BPF_JMP | BPF_JSET | BPF_X: /* (dst & src) */ |
|
case BPF_JMP32 | BPF_JSET | BPF_X: /* ((u32) dst & (u32) src) */ |
|
{ |
|
bool is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; |
|
|
|
mask = 0x7000; /* jnz */ |
|
/* nrk or ngrk %w1,%dst,%src */ |
|
EMIT4_RRF((is_jmp32 ? 0xb9f40000 : 0xb9e40000), |
|
REG_W1, dst_reg, src_reg); |
|
goto branch_oc; |
|
branch_ks: |
|
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; |
|
/* cfi or cgfi %dst,imm */ |
|
EMIT6_IMM(is_jmp32 ? 0xc20d0000 : 0xc20c0000, |
|
dst_reg, imm); |
|
if (!is_first_pass(jit) && |
|
can_use_rel(jit, addrs[i + off + 1])) { |
|
/* brc mask,off */ |
|
EMIT4_PCREL_RIC(0xa7040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} else { |
|
/* brcl mask,off */ |
|
EMIT6_PCREL_RILC(0xc0040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} |
|
break; |
|
branch_ku: |
|
/* lgfi %w1,imm (load sign extend imm) */ |
|
src_reg = REG_1; |
|
EMIT6_IMM(0xc0010000, src_reg, imm); |
|
goto branch_xu; |
|
branch_xs: |
|
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; |
|
if (!is_first_pass(jit) && |
|
can_use_rel(jit, addrs[i + off + 1])) { |
|
/* crj or cgrj %dst,%src,mask,off */ |
|
EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0076 : 0x0064), |
|
dst_reg, src_reg, i, off, mask); |
|
} else { |
|
/* cr or cgr %dst,%src */ |
|
if (is_jmp32) |
|
EMIT2(0x1900, dst_reg, src_reg); |
|
else |
|
EMIT4(0xb9200000, dst_reg, src_reg); |
|
/* brcl mask,off */ |
|
EMIT6_PCREL_RILC(0xc0040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} |
|
break; |
|
branch_xu: |
|
is_jmp32 = BPF_CLASS(insn->code) == BPF_JMP32; |
|
if (!is_first_pass(jit) && |
|
can_use_rel(jit, addrs[i + off + 1])) { |
|
/* clrj or clgrj %dst,%src,mask,off */ |
|
EMIT6_PCREL(0xec000000, (is_jmp32 ? 0x0077 : 0x0065), |
|
dst_reg, src_reg, i, off, mask); |
|
} else { |
|
/* clr or clgr %dst,%src */ |
|
if (is_jmp32) |
|
EMIT2(0x1500, dst_reg, src_reg); |
|
else |
|
EMIT4(0xb9210000, dst_reg, src_reg); |
|
/* brcl mask,off */ |
|
EMIT6_PCREL_RILC(0xc0040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} |
|
break; |
|
branch_oc: |
|
if (!is_first_pass(jit) && |
|
can_use_rel(jit, addrs[i + off + 1])) { |
|
/* brc mask,off */ |
|
EMIT4_PCREL_RIC(0xa7040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} else { |
|
/* brcl mask,off */ |
|
EMIT6_PCREL_RILC(0xc0040000, |
|
mask >> 12, addrs[i + off + 1]); |
|
} |
|
break; |
|
} |
|
default: /* too complex, give up */ |
|
pr_err("Unknown opcode %02x\n", insn->code); |
|
return -1; |
|
} |
|
|
|
if (probe_prg != -1) { |
|
/* |
|
* Handlers of certain exceptions leave psw.addr pointing to |
|
* the instruction directly after the failing one. Therefore, |
|
* create two exception table entries and also add a nop in |
|
* case two probing instructions come directly after each |
|
* other. |
|
*/ |
|
nop_prg = jit->prg; |
|
/* bcr 0,%0 */ |
|
_EMIT2(0x0700); |
|
err = bpf_jit_probe_mem(jit, fp, probe_prg, nop_prg); |
|
if (err < 0) |
|
return err; |
|
} |
|
|
|
return insn_count; |
|
} |
|
|
|
/* |
|
* Return whether new i-th instruction address does not violate any invariant |
|
*/ |
|
static bool bpf_is_new_addr_sane(struct bpf_jit *jit, int i) |
|
{ |
|
/* On the first pass anything goes */ |
|
if (is_first_pass(jit)) |
|
return true; |
|
|
|
/* The codegen pass must not change anything */ |
|
if (is_codegen_pass(jit)) |
|
return jit->addrs[i] == jit->prg; |
|
|
|
/* Passes in between must not increase code size */ |
|
return jit->addrs[i] >= jit->prg; |
|
} |
|
|
|
/* |
|
* Update the address of i-th instruction |
|
*/ |
|
static int bpf_set_addr(struct bpf_jit *jit, int i) |
|
{ |
|
int delta; |
|
|
|
if (is_codegen_pass(jit)) { |
|
delta = jit->prg - jit->addrs[i]; |
|
if (delta < 0) |
|
bpf_skip(jit, -delta); |
|
} |
|
if (WARN_ON_ONCE(!bpf_is_new_addr_sane(jit, i))) |
|
return -1; |
|
jit->addrs[i] = jit->prg; |
|
return 0; |
|
} |
|
|
|
/* |
|
* Compile eBPF program into s390x code |
|
*/ |
|
static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp, |
|
bool extra_pass, u32 stack_depth) |
|
{ |
|
int i, insn_count, lit32_size, lit64_size; |
|
|
|
jit->lit32 = jit->lit32_start; |
|
jit->lit64 = jit->lit64_start; |
|
jit->prg = 0; |
|
jit->excnt = 0; |
|
|
|
bpf_jit_prologue(jit, stack_depth); |
|
if (bpf_set_addr(jit, 0) < 0) |
|
return -1; |
|
for (i = 0; i < fp->len; i += insn_count) { |
|
insn_count = bpf_jit_insn(jit, fp, i, extra_pass, stack_depth); |
|
if (insn_count < 0) |
|
return -1; |
|
/* Next instruction address */ |
|
if (bpf_set_addr(jit, i + insn_count) < 0) |
|
return -1; |
|
} |
|
bpf_jit_epilogue(jit, stack_depth); |
|
|
|
lit32_size = jit->lit32 - jit->lit32_start; |
|
lit64_size = jit->lit64 - jit->lit64_start; |
|
jit->lit32_start = jit->prg; |
|
if (lit32_size) |
|
jit->lit32_start = ALIGN(jit->lit32_start, 4); |
|
jit->lit64_start = jit->lit32_start + lit32_size; |
|
if (lit64_size) |
|
jit->lit64_start = ALIGN(jit->lit64_start, 8); |
|
jit->size = jit->lit64_start + lit64_size; |
|
jit->size_prg = jit->prg; |
|
|
|
if (WARN_ON_ONCE(fp->aux->extable && |
|
jit->excnt != fp->aux->num_exentries)) |
|
/* Verifier bug - too many entries. */ |
|
return -1; |
|
|
|
return 0; |
|
} |
|
|
|
bool bpf_jit_needs_zext(void) |
|
{ |
|
return true; |
|
} |
|
|
|
struct s390_jit_data { |
|
struct bpf_binary_header *header; |
|
struct bpf_jit ctx; |
|
int pass; |
|
}; |
|
|
|
static struct bpf_binary_header *bpf_jit_alloc(struct bpf_jit *jit, |
|
struct bpf_prog *fp) |
|
{ |
|
struct bpf_binary_header *header; |
|
u32 extable_size; |
|
u32 code_size; |
|
|
|
/* We need two entries per insn. */ |
|
fp->aux->num_exentries *= 2; |
|
|
|
code_size = roundup(jit->size, |
|
__alignof__(struct exception_table_entry)); |
|
extable_size = fp->aux->num_exentries * |
|
sizeof(struct exception_table_entry); |
|
header = bpf_jit_binary_alloc(code_size + extable_size, &jit->prg_buf, |
|
8, jit_fill_hole); |
|
if (!header) |
|
return NULL; |
|
fp->aux->extable = (struct exception_table_entry *) |
|
(jit->prg_buf + code_size); |
|
return header; |
|
} |
|
|
|
/* |
|
* Compile eBPF program "fp" |
|
*/ |
|
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) |
|
{ |
|
u32 stack_depth = round_up(fp->aux->stack_depth, 8); |
|
struct bpf_prog *tmp, *orig_fp = fp; |
|
struct bpf_binary_header *header; |
|
struct s390_jit_data *jit_data; |
|
bool tmp_blinded = false; |
|
bool extra_pass = false; |
|
struct bpf_jit jit; |
|
int pass; |
|
|
|
if (!fp->jit_requested) |
|
return orig_fp; |
|
|
|
tmp = bpf_jit_blind_constants(fp); |
|
/* |
|
* If blinding was requested and we failed during blinding, |
|
* we must fall back to the interpreter. |
|
*/ |
|
if (IS_ERR(tmp)) |
|
return orig_fp; |
|
if (tmp != fp) { |
|
tmp_blinded = true; |
|
fp = tmp; |
|
} |
|
|
|
jit_data = fp->aux->jit_data; |
|
if (!jit_data) { |
|
jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); |
|
if (!jit_data) { |
|
fp = orig_fp; |
|
goto out; |
|
} |
|
fp->aux->jit_data = jit_data; |
|
} |
|
if (jit_data->ctx.addrs) { |
|
jit = jit_data->ctx; |
|
header = jit_data->header; |
|
extra_pass = true; |
|
pass = jit_data->pass + 1; |
|
goto skip_init_ctx; |
|
} |
|
|
|
memset(&jit, 0, sizeof(jit)); |
|
jit.addrs = kvcalloc(fp->len + 1, sizeof(*jit.addrs), GFP_KERNEL); |
|
if (jit.addrs == NULL) { |
|
fp = orig_fp; |
|
goto out; |
|
} |
|
/* |
|
* Three initial passes: |
|
* - 1/2: Determine clobbered registers |
|
* - 3: Calculate program size and addrs arrray |
|
*/ |
|
for (pass = 1; pass <= 3; pass++) { |
|
if (bpf_jit_prog(&jit, fp, extra_pass, stack_depth)) { |
|
fp = orig_fp; |
|
goto free_addrs; |
|
} |
|
} |
|
/* |
|
* Final pass: Allocate and generate program |
|
*/ |
|
header = bpf_jit_alloc(&jit, fp); |
|
if (!header) { |
|
fp = orig_fp; |
|
goto free_addrs; |
|
} |
|
skip_init_ctx: |
|
if (bpf_jit_prog(&jit, fp, extra_pass, stack_depth)) { |
|
bpf_jit_binary_free(header); |
|
fp = orig_fp; |
|
goto free_addrs; |
|
} |
|
if (bpf_jit_enable > 1) { |
|
bpf_jit_dump(fp->len, jit.size, pass, jit.prg_buf); |
|
print_fn_code(jit.prg_buf, jit.size_prg); |
|
} |
|
if (!fp->is_func || extra_pass) { |
|
bpf_jit_binary_lock_ro(header); |
|
} else { |
|
jit_data->header = header; |
|
jit_data->ctx = jit; |
|
jit_data->pass = pass; |
|
} |
|
fp->bpf_func = (void *) jit.prg_buf; |
|
fp->jited = 1; |
|
fp->jited_len = jit.size; |
|
|
|
if (!fp->is_func || extra_pass) { |
|
bpf_prog_fill_jited_linfo(fp, jit.addrs + 1); |
|
free_addrs: |
|
kvfree(jit.addrs); |
|
kfree(jit_data); |
|
fp->aux->jit_data = NULL; |
|
} |
|
out: |
|
if (tmp_blinded) |
|
bpf_jit_prog_release_other(fp, fp == orig_fp ? |
|
tmp : orig_fp); |
|
return fp; |
|
}
|
|
|