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![Naveen N. Rao](/assets/img/avatar_default.png)
Convert bpf_to_ppc() to a macro to help simplify its usage since codegen_context is available in all places it is used. Adopt it also for powerpc64 for uniformity and get rid of the global b2p structure. Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/09f0540ce3e0cd4120b5b33993b5e73b6ef9e979.1644834730.git.naveen.n.rao@linux.vnet.ibm.com
1209 lines
36 KiB
C
1209 lines
36 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* eBPF JIT compiler for PPC32
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*
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* Copyright 2020 Christophe Leroy <christophe.leroy@csgroup.eu>
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* CS GROUP France
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*
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* Based on PPC64 eBPF JIT compiler by Naveen N. Rao
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*/
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#include <linux/moduleloader.h>
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#include <asm/cacheflush.h>
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#include <asm/asm-compat.h>
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#include <linux/netdevice.h>
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#include <linux/filter.h>
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#include <linux/if_vlan.h>
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#include <asm/kprobes.h>
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#include <linux/bpf.h>
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#include "bpf_jit.h"
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/*
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* Stack layout:
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*
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* [ prev sp ] <-------------
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* [ nv gpr save area ] 16 * 4 |
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* fp (r31) --> [ ebpf stack space ] upto 512 |
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* [ frame header ] 16 |
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* sp (r1) ---> [ stack pointer ] --------------
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*/
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/* for gpr non volatile registers r17 to r31 (14) + tail call */
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#define BPF_PPC_STACK_SAVE (15 * 4 + 4)
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/* stack frame, ensure this is quadword aligned */
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#define BPF_PPC_STACKFRAME(ctx) (STACK_FRAME_MIN_SIZE + BPF_PPC_STACK_SAVE + (ctx)->stack_size)
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#define PPC_EX32(r, i) EMIT(PPC_RAW_LI((r), (i) < 0 ? -1 : 0))
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/* PPC NVR range -- update this if we ever use NVRs below r17 */
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#define BPF_PPC_NVR_MIN _R17
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#define BPF_PPC_TC _R16
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/* BPF register usage */
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#define TMP_REG (MAX_BPF_JIT_REG + 0)
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/* BPF to ppc register mappings */
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void bpf_jit_init_reg_mapping(struct codegen_context *ctx)
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{
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/* function return value */
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ctx->b2p[BPF_REG_0] = _R12;
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/* function arguments */
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ctx->b2p[BPF_REG_1] = _R4;
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ctx->b2p[BPF_REG_2] = _R6;
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ctx->b2p[BPF_REG_3] = _R8;
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ctx->b2p[BPF_REG_4] = _R10;
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ctx->b2p[BPF_REG_5] = _R22;
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/* non volatile registers */
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ctx->b2p[BPF_REG_6] = _R24;
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ctx->b2p[BPF_REG_7] = _R26;
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ctx->b2p[BPF_REG_8] = _R28;
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ctx->b2p[BPF_REG_9] = _R30;
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/* frame pointer aka BPF_REG_10 */
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ctx->b2p[BPF_REG_FP] = _R18;
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/* eBPF jit internal registers */
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ctx->b2p[BPF_REG_AX] = _R20;
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ctx->b2p[TMP_REG] = _R31; /* 32 bits */
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}
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static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg)
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{
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if ((reg >= BPF_PPC_NVR_MIN && reg < 32) || reg == BPF_PPC_TC)
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return BPF_PPC_STACKFRAME(ctx) - 4 * (32 - reg);
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WARN(true, "BPF JIT is asking about unknown registers, will crash the stack");
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/* Use the hole we have left for alignment */
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return BPF_PPC_STACKFRAME(ctx) - 4;
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}
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#define SEEN_VREG_MASK 0x1ff80000 /* Volatile registers r3-r12 */
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#define SEEN_NVREG_FULL_MASK 0x0003ffff /* Non volatile registers r14-r31 */
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#define SEEN_NVREG_TEMP_MASK 0x00001e01 /* BPF_REG_5, BPF_REG_AX, TMP_REG */
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void bpf_jit_realloc_regs(struct codegen_context *ctx)
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{
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unsigned int nvreg_mask;
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if (ctx->seen & SEEN_FUNC)
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nvreg_mask = SEEN_NVREG_TEMP_MASK;
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else
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nvreg_mask = SEEN_NVREG_FULL_MASK;
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while (ctx->seen & nvreg_mask &&
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(ctx->seen & SEEN_VREG_MASK) != SEEN_VREG_MASK) {
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int old = 32 - fls(ctx->seen & (nvreg_mask & 0xaaaaaaab));
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int new = 32 - fls(~ctx->seen & (SEEN_VREG_MASK & 0xaaaaaaaa));
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int i;
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for (i = BPF_REG_0; i <= TMP_REG; i++) {
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if (ctx->b2p[i] != old)
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continue;
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ctx->b2p[i] = new;
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bpf_set_seen_register(ctx, new);
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bpf_clear_seen_register(ctx, old);
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if (i != TMP_REG) {
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bpf_set_seen_register(ctx, new - 1);
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bpf_clear_seen_register(ctx, old - 1);
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}
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break;
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}
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}
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}
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void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx)
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{
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int i;
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/* First arg comes in as a 32 bits pointer. */
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EMIT(PPC_RAW_MR(bpf_to_ppc(BPF_REG_1), _R3));
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EMIT(PPC_RAW_LI(bpf_to_ppc(BPF_REG_1) - 1, 0));
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EMIT(PPC_RAW_STWU(_R1, _R1, -BPF_PPC_STACKFRAME(ctx)));
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/*
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* Initialize tail_call_cnt in stack frame if we do tail calls.
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* Otherwise, put in NOPs so that it can be skipped when we are
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* invoked through a tail call.
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*/
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if (ctx->seen & SEEN_TAILCALL)
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EMIT(PPC_RAW_STW(bpf_to_ppc(BPF_REG_1) - 1, _R1,
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bpf_jit_stack_offsetof(ctx, BPF_PPC_TC)));
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else
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EMIT(PPC_RAW_NOP());
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#define BPF_TAILCALL_PROLOGUE_SIZE 16
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/*
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* We need a stack frame, but we don't necessarily need to
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* save/restore LR unless we call other functions
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*/
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_MFLR(_R0));
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/*
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* Back up non-volatile regs -- registers r18-r31
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*/
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for (i = BPF_PPC_NVR_MIN; i <= 31; i++)
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if (bpf_is_seen_register(ctx, i))
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EMIT(PPC_RAW_STW(i, _R1, bpf_jit_stack_offsetof(ctx, i)));
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/* If needed retrieve arguments 9 and 10, ie 5th 64 bits arg.*/
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if (bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_5))) {
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EMIT(PPC_RAW_LWZ(bpf_to_ppc(BPF_REG_5) - 1, _R1, BPF_PPC_STACKFRAME(ctx)) + 8);
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EMIT(PPC_RAW_LWZ(bpf_to_ppc(BPF_REG_5), _R1, BPF_PPC_STACKFRAME(ctx)) + 12);
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}
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/* Setup frame pointer to point to the bpf stack area */
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if (bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_FP))) {
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EMIT(PPC_RAW_LI(bpf_to_ppc(BPF_REG_FP) - 1, 0));
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EMIT(PPC_RAW_ADDI(bpf_to_ppc(BPF_REG_FP), _R1,
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STACK_FRAME_MIN_SIZE + ctx->stack_size));
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}
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_STW(_R0, _R1, BPF_PPC_STACKFRAME(ctx) + PPC_LR_STKOFF));
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}
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static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx)
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{
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int i;
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/* Restore NVRs */
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for (i = BPF_PPC_NVR_MIN; i <= 31; i++)
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if (bpf_is_seen_register(ctx, i))
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EMIT(PPC_RAW_LWZ(i, _R1, bpf_jit_stack_offsetof(ctx, i)));
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}
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void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
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{
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EMIT(PPC_RAW_MR(_R3, bpf_to_ppc(BPF_REG_0)));
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bpf_jit_emit_common_epilogue(image, ctx);
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/* Tear down our stack frame */
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_LWZ(_R0, _R1, BPF_PPC_STACKFRAME(ctx) + PPC_LR_STKOFF));
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EMIT(PPC_RAW_ADDI(_R1, _R1, BPF_PPC_STACKFRAME(ctx)));
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_MTLR(_R0));
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EMIT(PPC_RAW_BLR());
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}
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int bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func)
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{
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s32 rel = (s32)func - (s32)(image + ctx->idx);
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if (image && rel < 0x2000000 && rel >= -0x2000000) {
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PPC_BL(func);
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EMIT(PPC_RAW_NOP());
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EMIT(PPC_RAW_NOP());
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EMIT(PPC_RAW_NOP());
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} else {
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/* Load function address into r0 */
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EMIT(PPC_RAW_LIS(_R0, IMM_H(func)));
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EMIT(PPC_RAW_ORI(_R0, _R0, IMM_L(func)));
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EMIT(PPC_RAW_MTCTR(_R0));
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EMIT(PPC_RAW_BCTRL());
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}
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return 0;
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}
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static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 out)
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{
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/*
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* By now, the eBPF program has already setup parameters in r3-r6
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* r3-r4/BPF_REG_1 - pointer to ctx -- passed as is to the next bpf program
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* r5-r6/BPF_REG_2 - pointer to bpf_array
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* r7-r8/BPF_REG_3 - index in bpf_array
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*/
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int b2p_bpf_array = bpf_to_ppc(BPF_REG_2);
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int b2p_index = bpf_to_ppc(BPF_REG_3);
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/*
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* if (index >= array->map.max_entries)
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* goto out;
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*/
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EMIT(PPC_RAW_LWZ(_R0, b2p_bpf_array, offsetof(struct bpf_array, map.max_entries)));
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EMIT(PPC_RAW_CMPLW(b2p_index, _R0));
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EMIT(PPC_RAW_LWZ(_R0, _R1, bpf_jit_stack_offsetof(ctx, BPF_PPC_TC)));
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PPC_BCC_SHORT(COND_GE, out);
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/*
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* if (tail_call_cnt >= MAX_TAIL_CALL_CNT)
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* goto out;
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*/
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EMIT(PPC_RAW_CMPLWI(_R0, MAX_TAIL_CALL_CNT));
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/* tail_call_cnt++; */
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EMIT(PPC_RAW_ADDIC(_R0, _R0, 1));
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PPC_BCC_SHORT(COND_GE, out);
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/* prog = array->ptrs[index]; */
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EMIT(PPC_RAW_RLWINM(_R3, b2p_index, 2, 0, 29));
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EMIT(PPC_RAW_ADD(_R3, _R3, b2p_bpf_array));
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EMIT(PPC_RAW_LWZ(_R3, _R3, offsetof(struct bpf_array, ptrs)));
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EMIT(PPC_RAW_STW(_R0, _R1, bpf_jit_stack_offsetof(ctx, BPF_PPC_TC)));
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/*
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* if (prog == NULL)
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* goto out;
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*/
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EMIT(PPC_RAW_CMPLWI(_R3, 0));
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PPC_BCC_SHORT(COND_EQ, out);
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/* goto *(prog->bpf_func + prologue_size); */
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EMIT(PPC_RAW_LWZ(_R3, _R3, offsetof(struct bpf_prog, bpf_func)));
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_LWZ(_R0, _R1, BPF_PPC_STACKFRAME(ctx) + PPC_LR_STKOFF));
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EMIT(PPC_RAW_ADDIC(_R3, _R3, BPF_TAILCALL_PROLOGUE_SIZE));
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if (ctx->seen & SEEN_FUNC)
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EMIT(PPC_RAW_MTLR(_R0));
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EMIT(PPC_RAW_MTCTR(_R3));
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EMIT(PPC_RAW_MR(_R3, bpf_to_ppc(BPF_REG_1)));
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/* tear restore NVRs, ... */
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bpf_jit_emit_common_epilogue(image, ctx);
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EMIT(PPC_RAW_BCTR());
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/* out: */
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return 0;
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}
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/* Assemble the body code between the prologue & epilogue */
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int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx,
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u32 *addrs, int pass)
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{
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const struct bpf_insn *insn = fp->insnsi;
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int flen = fp->len;
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int i, ret;
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/* Start of epilogue code - will only be valid 2nd pass onwards */
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u32 exit_addr = addrs[flen];
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for (i = 0; i < flen; i++) {
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u32 code = insn[i].code;
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u32 dst_reg = bpf_to_ppc(insn[i].dst_reg);
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u32 dst_reg_h = dst_reg - 1;
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u32 src_reg = bpf_to_ppc(insn[i].src_reg);
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u32 src_reg_h = src_reg - 1;
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u32 tmp_reg = bpf_to_ppc(TMP_REG);
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u32 size = BPF_SIZE(code);
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s16 off = insn[i].off;
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s32 imm = insn[i].imm;
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bool func_addr_fixed;
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u64 func_addr;
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u32 true_cond;
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u32 tmp_idx;
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int j;
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/*
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* addrs[] maps a BPF bytecode address into a real offset from
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* the start of the body code.
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*/
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addrs[i] = ctx->idx * 4;
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/*
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* As an optimization, we note down which registers
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* are used so that we can only save/restore those in our
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* prologue and epilogue. We do this here regardless of whether
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* the actual BPF instruction uses src/dst registers or not
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* (for instance, BPF_CALL does not use them). The expectation
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* is that those instructions will have src_reg/dst_reg set to
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* 0. Even otherwise, we just lose some prologue/epilogue
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* optimization but everything else should work without
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* any issues.
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*/
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if (dst_reg >= 3 && dst_reg < 32) {
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bpf_set_seen_register(ctx, dst_reg);
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bpf_set_seen_register(ctx, dst_reg_h);
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}
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if (src_reg >= 3 && src_reg < 32) {
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bpf_set_seen_register(ctx, src_reg);
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bpf_set_seen_register(ctx, src_reg_h);
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}
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switch (code) {
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/*
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* Arithmetic operations: ADD/SUB/MUL/DIV/MOD/NEG
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*/
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case BPF_ALU | BPF_ADD | BPF_X: /* (u32) dst += (u32) src */
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EMIT(PPC_RAW_ADD(dst_reg, dst_reg, src_reg));
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break;
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case BPF_ALU64 | BPF_ADD | BPF_X: /* dst += src */
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EMIT(PPC_RAW_ADDC(dst_reg, dst_reg, src_reg));
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EMIT(PPC_RAW_ADDE(dst_reg_h, dst_reg_h, src_reg_h));
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break;
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case BPF_ALU | BPF_SUB | BPF_X: /* (u32) dst -= (u32) src */
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EMIT(PPC_RAW_SUB(dst_reg, dst_reg, src_reg));
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break;
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case BPF_ALU64 | BPF_SUB | BPF_X: /* dst -= src */
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EMIT(PPC_RAW_SUBFC(dst_reg, src_reg, dst_reg));
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EMIT(PPC_RAW_SUBFE(dst_reg_h, src_reg_h, dst_reg_h));
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break;
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case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */
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imm = -imm;
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fallthrough;
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case BPF_ALU | BPF_ADD | BPF_K: /* (u32) dst += (u32) imm */
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if (IMM_HA(imm) & 0xffff)
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EMIT(PPC_RAW_ADDIS(dst_reg, dst_reg, IMM_HA(imm)));
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if (IMM_L(imm))
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EMIT(PPC_RAW_ADDI(dst_reg, dst_reg, IMM_L(imm)));
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break;
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case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */
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imm = -imm;
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fallthrough;
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case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */
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if (!imm)
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break;
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if (imm >= -32768 && imm < 32768) {
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EMIT(PPC_RAW_ADDIC(dst_reg, dst_reg, imm));
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} else {
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PPC_LI32(_R0, imm);
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EMIT(PPC_RAW_ADDC(dst_reg, dst_reg, _R0));
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}
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if (imm >= 0 || (BPF_OP(code) == BPF_SUB && imm == 0x80000000))
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EMIT(PPC_RAW_ADDZE(dst_reg_h, dst_reg_h));
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else
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EMIT(PPC_RAW_ADDME(dst_reg_h, dst_reg_h));
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break;
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case BPF_ALU64 | BPF_MUL | BPF_X: /* dst *= src */
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bpf_set_seen_register(ctx, tmp_reg);
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EMIT(PPC_RAW_MULW(_R0, dst_reg, src_reg_h));
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EMIT(PPC_RAW_MULW(dst_reg_h, dst_reg_h, src_reg));
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EMIT(PPC_RAW_MULHWU(tmp_reg, dst_reg, src_reg));
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EMIT(PPC_RAW_MULW(dst_reg, dst_reg, src_reg));
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EMIT(PPC_RAW_ADD(dst_reg_h, dst_reg_h, _R0));
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EMIT(PPC_RAW_ADD(dst_reg_h, dst_reg_h, tmp_reg));
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break;
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case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */
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EMIT(PPC_RAW_MULW(dst_reg, dst_reg, src_reg));
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break;
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case BPF_ALU | BPF_MUL | BPF_K: /* (u32) dst *= (u32) imm */
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if (imm >= -32768 && imm < 32768) {
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EMIT(PPC_RAW_MULI(dst_reg, dst_reg, imm));
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} else {
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PPC_LI32(_R0, imm);
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EMIT(PPC_RAW_MULW(dst_reg, dst_reg, _R0));
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}
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break;
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case BPF_ALU64 | BPF_MUL | BPF_K: /* dst *= imm */
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if (!imm) {
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PPC_LI32(dst_reg, 0);
|
|
PPC_LI32(dst_reg_h, 0);
|
|
break;
|
|
}
|
|
if (imm == 1)
|
|
break;
|
|
if (imm == -1) {
|
|
EMIT(PPC_RAW_SUBFIC(dst_reg, dst_reg, 0));
|
|
EMIT(PPC_RAW_SUBFZE(dst_reg_h, dst_reg_h));
|
|
break;
|
|
}
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
PPC_LI32(tmp_reg, imm);
|
|
EMIT(PPC_RAW_MULW(dst_reg_h, dst_reg_h, tmp_reg));
|
|
if (imm < 0)
|
|
EMIT(PPC_RAW_SUB(dst_reg_h, dst_reg_h, dst_reg));
|
|
EMIT(PPC_RAW_MULHWU(_R0, dst_reg, tmp_reg));
|
|
EMIT(PPC_RAW_MULW(dst_reg, dst_reg, tmp_reg));
|
|
EMIT(PPC_RAW_ADD(dst_reg_h, dst_reg_h, _R0));
|
|
break;
|
|
case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */
|
|
EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */
|
|
EMIT(PPC_RAW_DIVWU(_R0, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_MULW(_R0, src_reg, _R0));
|
|
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, _R0));
|
|
break;
|
|
case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */
|
|
return -EOPNOTSUPP;
|
|
case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */
|
|
return -EOPNOTSUPP;
|
|
case BPF_ALU | BPF_DIV | BPF_K: /* (u32) dst /= (u32) imm */
|
|
if (!imm)
|
|
return -EINVAL;
|
|
if (imm == 1)
|
|
break;
|
|
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, _R0));
|
|
break;
|
|
case BPF_ALU | BPF_MOD | BPF_K: /* (u32) dst %= (u32) imm */
|
|
if (!imm)
|
|
return -EINVAL;
|
|
|
|
if (!is_power_of_2((u32)imm)) {
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
PPC_LI32(tmp_reg, imm);
|
|
EMIT(PPC_RAW_DIVWU(_R0, dst_reg, tmp_reg));
|
|
EMIT(PPC_RAW_MULW(_R0, tmp_reg, _R0));
|
|
EMIT(PPC_RAW_SUB(dst_reg, dst_reg, _R0));
|
|
break;
|
|
}
|
|
if (imm == 1)
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
else
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 32 - ilog2((u32)imm), 31));
|
|
|
|
break;
|
|
case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */
|
|
if (!imm)
|
|
return -EINVAL;
|
|
if (imm < 0)
|
|
imm = -imm;
|
|
if (!is_power_of_2(imm))
|
|
return -EOPNOTSUPP;
|
|
if (imm == 1)
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
else
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 32 - ilog2(imm), 31));
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
break;
|
|
case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */
|
|
if (!imm)
|
|
return -EINVAL;
|
|
if (!is_power_of_2(abs(imm)))
|
|
return -EOPNOTSUPP;
|
|
|
|
if (imm < 0) {
|
|
EMIT(PPC_RAW_SUBFIC(dst_reg, dst_reg, 0));
|
|
EMIT(PPC_RAW_SUBFZE(dst_reg_h, dst_reg_h));
|
|
imm = -imm;
|
|
}
|
|
if (imm == 1)
|
|
break;
|
|
imm = ilog2(imm);
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 32 - imm, imm, 31));
|
|
EMIT(PPC_RAW_RLWIMI(dst_reg, dst_reg_h, 32 - imm, 0, imm - 1));
|
|
EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg_h, imm));
|
|
break;
|
|
case BPF_ALU | BPF_NEG: /* (u32) dst = -dst */
|
|
EMIT(PPC_RAW_NEG(dst_reg, dst_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_NEG: /* dst = -dst */
|
|
EMIT(PPC_RAW_SUBFIC(dst_reg, dst_reg, 0));
|
|
EMIT(PPC_RAW_SUBFZE(dst_reg_h, dst_reg_h));
|
|
break;
|
|
|
|
/*
|
|
* Logical operations: AND/OR/XOR/[A]LSH/[A]RSH
|
|
*/
|
|
case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */
|
|
EMIT(PPC_RAW_AND(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_AND(dst_reg_h, dst_reg_h, src_reg_h));
|
|
break;
|
|
case BPF_ALU | BPF_AND | BPF_X: /* (u32) dst = dst & src */
|
|
EMIT(PPC_RAW_AND(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */
|
|
if (imm >= 0)
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
fallthrough;
|
|
case BPF_ALU | BPF_AND | BPF_K: /* (u32) dst = dst & imm */
|
|
if (!IMM_H(imm)) {
|
|
EMIT(PPC_RAW_ANDI(dst_reg, dst_reg, IMM_L(imm)));
|
|
} else if (!IMM_L(imm)) {
|
|
EMIT(PPC_RAW_ANDIS(dst_reg, dst_reg, IMM_H(imm)));
|
|
} else if (imm == (((1 << fls(imm)) - 1) ^ ((1 << (ffs(i) - 1)) - 1))) {
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0,
|
|
32 - fls(imm), 32 - ffs(imm)));
|
|
} else {
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_AND(dst_reg, dst_reg, _R0));
|
|
}
|
|
break;
|
|
case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_OR(dst_reg_h, dst_reg_h, src_reg_h));
|
|
break;
|
|
case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_OR | BPF_K:/* dst = dst | imm */
|
|
/* Sign-extended */
|
|
if (imm < 0)
|
|
EMIT(PPC_RAW_LI(dst_reg_h, -1));
|
|
fallthrough;
|
|
case BPF_ALU | BPF_OR | BPF_K:/* dst = (u32) dst | (u32) imm */
|
|
if (IMM_L(imm))
|
|
EMIT(PPC_RAW_ORI(dst_reg, dst_reg, IMM_L(imm)));
|
|
if (IMM_H(imm))
|
|
EMIT(PPC_RAW_ORIS(dst_reg, dst_reg, IMM_H(imm)));
|
|
break;
|
|
case BPF_ALU64 | BPF_XOR | BPF_X: /* dst ^= src */
|
|
if (dst_reg == src_reg) {
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
} else {
|
|
EMIT(PPC_RAW_XOR(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_XOR(dst_reg_h, dst_reg_h, src_reg_h));
|
|
}
|
|
break;
|
|
case BPF_ALU | BPF_XOR | BPF_X: /* (u32) dst ^= src */
|
|
if (dst_reg == src_reg)
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
else
|
|
EMIT(PPC_RAW_XOR(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_XOR | BPF_K: /* dst ^= imm */
|
|
if (imm < 0)
|
|
EMIT(PPC_RAW_NOR(dst_reg_h, dst_reg_h, dst_reg_h));
|
|
fallthrough;
|
|
case BPF_ALU | BPF_XOR | BPF_K: /* (u32) dst ^= (u32) imm */
|
|
if (IMM_L(imm))
|
|
EMIT(PPC_RAW_XORI(dst_reg, dst_reg, IMM_L(imm)));
|
|
if (IMM_H(imm))
|
|
EMIT(PPC_RAW_XORIS(dst_reg, dst_reg, IMM_H(imm)));
|
|
break;
|
|
case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */
|
|
EMIT(PPC_RAW_SLW(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_LSH | BPF_X: /* dst <<= src; */
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
EMIT(PPC_RAW_SUBFIC(_R0, src_reg, 32));
|
|
EMIT(PPC_RAW_SLW(dst_reg_h, dst_reg_h, src_reg));
|
|
EMIT(PPC_RAW_ADDI(tmp_reg, src_reg, 32));
|
|
EMIT(PPC_RAW_SRW(_R0, dst_reg, _R0));
|
|
EMIT(PPC_RAW_SLW(tmp_reg, dst_reg, tmp_reg));
|
|
EMIT(PPC_RAW_OR(dst_reg_h, dst_reg_h, _R0));
|
|
EMIT(PPC_RAW_SLW(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_OR(dst_reg_h, dst_reg_h, tmp_reg));
|
|
break;
|
|
case BPF_ALU | BPF_LSH | BPF_K: /* (u32) dst <<= (u32) imm */
|
|
if (!imm)
|
|
break;
|
|
EMIT(PPC_RAW_SLWI(dst_reg, dst_reg, imm));
|
|
break;
|
|
case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<= imm */
|
|
if (imm < 0)
|
|
return -EINVAL;
|
|
if (!imm)
|
|
break;
|
|
if (imm < 32) {
|
|
EMIT(PPC_RAW_RLWINM(dst_reg_h, dst_reg_h, imm, 0, 31 - imm));
|
|
EMIT(PPC_RAW_RLWIMI(dst_reg_h, dst_reg, imm, 32 - imm, 31));
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, imm, 0, 31 - imm));
|
|
break;
|
|
}
|
|
if (imm < 64)
|
|
EMIT(PPC_RAW_RLWINM(dst_reg_h, dst_reg, imm, 0, 31 - imm));
|
|
else
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
break;
|
|
case BPF_ALU | BPF_RSH | BPF_X: /* (u32) dst >>= (u32) src */
|
|
EMIT(PPC_RAW_SRW(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_RSH | BPF_X: /* dst >>= src */
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
EMIT(PPC_RAW_SUBFIC(_R0, src_reg, 32));
|
|
EMIT(PPC_RAW_SRW(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_ADDI(tmp_reg, src_reg, 32));
|
|
EMIT(PPC_RAW_SLW(_R0, dst_reg_h, _R0));
|
|
EMIT(PPC_RAW_SRW(tmp_reg, dst_reg_h, tmp_reg));
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, _R0));
|
|
EMIT(PPC_RAW_SRW(dst_reg_h, dst_reg_h, src_reg));
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, tmp_reg));
|
|
break;
|
|
case BPF_ALU | BPF_RSH | BPF_K: /* (u32) dst >>= (u32) imm */
|
|
if (!imm)
|
|
break;
|
|
EMIT(PPC_RAW_SRWI(dst_reg, dst_reg, imm));
|
|
break;
|
|
case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */
|
|
if (imm < 0)
|
|
return -EINVAL;
|
|
if (!imm)
|
|
break;
|
|
if (imm < 32) {
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 32 - imm, imm, 31));
|
|
EMIT(PPC_RAW_RLWIMI(dst_reg, dst_reg_h, 32 - imm, 0, imm - 1));
|
|
EMIT(PPC_RAW_RLWINM(dst_reg_h, dst_reg_h, 32 - imm, imm, 31));
|
|
break;
|
|
}
|
|
if (imm < 64)
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg_h, 64 - imm, imm - 32, 31));
|
|
else
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
break;
|
|
case BPF_ALU | BPF_ARSH | BPF_X: /* (s32) dst >>= src */
|
|
EMIT(PPC_RAW_SRAW(dst_reg, dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_ARSH | BPF_X: /* (s64) dst >>= src */
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
EMIT(PPC_RAW_SUBFIC(_R0, src_reg, 32));
|
|
EMIT(PPC_RAW_SRW(dst_reg, dst_reg, src_reg));
|
|
EMIT(PPC_RAW_SLW(_R0, dst_reg_h, _R0));
|
|
EMIT(PPC_RAW_ADDI(tmp_reg, src_reg, 32));
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, _R0));
|
|
EMIT(PPC_RAW_RLWINM(_R0, tmp_reg, 0, 26, 26));
|
|
EMIT(PPC_RAW_SRAW(tmp_reg, dst_reg_h, tmp_reg));
|
|
EMIT(PPC_RAW_SRAW(dst_reg_h, dst_reg_h, src_reg));
|
|
EMIT(PPC_RAW_SLW(tmp_reg, tmp_reg, _R0));
|
|
EMIT(PPC_RAW_OR(dst_reg, dst_reg, tmp_reg));
|
|
break;
|
|
case BPF_ALU | BPF_ARSH | BPF_K: /* (s32) dst >>= imm */
|
|
if (!imm)
|
|
break;
|
|
EMIT(PPC_RAW_SRAWI(dst_reg, dst_reg, imm));
|
|
break;
|
|
case BPF_ALU64 | BPF_ARSH | BPF_K: /* (s64) dst >>= imm */
|
|
if (imm < 0)
|
|
return -EINVAL;
|
|
if (!imm)
|
|
break;
|
|
if (imm < 32) {
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 32 - imm, imm, 31));
|
|
EMIT(PPC_RAW_RLWIMI(dst_reg, dst_reg_h, 32 - imm, 0, imm - 1));
|
|
EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg_h, imm));
|
|
break;
|
|
}
|
|
if (imm < 64)
|
|
EMIT(PPC_RAW_SRAWI(dst_reg, dst_reg_h, imm - 32));
|
|
else
|
|
EMIT(PPC_RAW_SRAWI(dst_reg, dst_reg_h, 31));
|
|
EMIT(PPC_RAW_SRAWI(dst_reg_h, dst_reg_h, 31));
|
|
break;
|
|
|
|
/*
|
|
* MOV
|
|
*/
|
|
case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */
|
|
if (dst_reg == src_reg)
|
|
break;
|
|
EMIT(PPC_RAW_MR(dst_reg, src_reg));
|
|
EMIT(PPC_RAW_MR(dst_reg_h, src_reg_h));
|
|
break;
|
|
case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */
|
|
/* special mov32 for zext */
|
|
if (imm == 1)
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
else if (dst_reg != src_reg)
|
|
EMIT(PPC_RAW_MR(dst_reg, src_reg));
|
|
break;
|
|
case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = (s64) imm */
|
|
PPC_LI32(dst_reg, imm);
|
|
PPC_EX32(dst_reg_h, imm);
|
|
break;
|
|
case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */
|
|
PPC_LI32(dst_reg, imm);
|
|
break;
|
|
|
|
/*
|
|
* BPF_FROM_BE/LE
|
|
*/
|
|
case BPF_ALU | BPF_END | BPF_FROM_LE:
|
|
switch (imm) {
|
|
case 16:
|
|
/* Copy 16 bits to upper part */
|
|
EMIT(PPC_RAW_RLWIMI(dst_reg, dst_reg, 16, 0, 15));
|
|
/* Rotate 8 bits right & mask */
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 24, 16, 31));
|
|
break;
|
|
case 32:
|
|
/*
|
|
* Rotate word left by 8 bits:
|
|
* 2 bytes are already in their final position
|
|
* -- byte 2 and 4 (of bytes 1, 2, 3 and 4)
|
|
*/
|
|
EMIT(PPC_RAW_RLWINM(_R0, dst_reg, 8, 0, 31));
|
|
/* Rotate 24 bits and insert byte 1 */
|
|
EMIT(PPC_RAW_RLWIMI(_R0, dst_reg, 24, 0, 7));
|
|
/* Rotate 24 bits and insert byte 3 */
|
|
EMIT(PPC_RAW_RLWIMI(_R0, dst_reg, 24, 16, 23));
|
|
EMIT(PPC_RAW_MR(dst_reg, _R0));
|
|
break;
|
|
case 64:
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
EMIT(PPC_RAW_RLWINM(tmp_reg, dst_reg, 8, 0, 31));
|
|
EMIT(PPC_RAW_RLWINM(_R0, dst_reg_h, 8, 0, 31));
|
|
/* Rotate 24 bits and insert byte 1 */
|
|
EMIT(PPC_RAW_RLWIMI(tmp_reg, dst_reg, 24, 0, 7));
|
|
EMIT(PPC_RAW_RLWIMI(_R0, dst_reg_h, 24, 0, 7));
|
|
/* Rotate 24 bits and insert byte 3 */
|
|
EMIT(PPC_RAW_RLWIMI(tmp_reg, dst_reg, 24, 16, 23));
|
|
EMIT(PPC_RAW_RLWIMI(_R0, dst_reg_h, 24, 16, 23));
|
|
EMIT(PPC_RAW_MR(dst_reg, _R0));
|
|
EMIT(PPC_RAW_MR(dst_reg_h, tmp_reg));
|
|
break;
|
|
}
|
|
break;
|
|
case BPF_ALU | BPF_END | BPF_FROM_BE:
|
|
switch (imm) {
|
|
case 16:
|
|
/* zero-extend 16 bits into 32 bits */
|
|
EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 16, 31));
|
|
break;
|
|
case 32:
|
|
case 64:
|
|
/* nop */
|
|
break;
|
|
}
|
|
break;
|
|
|
|
/*
|
|
* BPF_ST NOSPEC (speculation barrier)
|
|
*/
|
|
case BPF_ST | BPF_NOSPEC:
|
|
break;
|
|
|
|
/*
|
|
* BPF_ST(X)
|
|
*/
|
|
case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src */
|
|
EMIT(PPC_RAW_STB(src_reg, dst_reg, off));
|
|
break;
|
|
case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_STB(_R0, dst_reg, off));
|
|
break;
|
|
case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */
|
|
EMIT(PPC_RAW_STH(src_reg, dst_reg, off));
|
|
break;
|
|
case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_STH(_R0, dst_reg, off));
|
|
break;
|
|
case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */
|
|
EMIT(PPC_RAW_STW(src_reg, dst_reg, off));
|
|
break;
|
|
case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_STW(_R0, dst_reg, off));
|
|
break;
|
|
case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */
|
|
EMIT(PPC_RAW_STW(src_reg_h, dst_reg, off));
|
|
EMIT(PPC_RAW_STW(src_reg, dst_reg, off + 4));
|
|
break;
|
|
case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_STW(_R0, dst_reg, off + 4));
|
|
PPC_EX32(_R0, imm);
|
|
EMIT(PPC_RAW_STW(_R0, dst_reg, off));
|
|
break;
|
|
|
|
/*
|
|
* BPF_STX ATOMIC (atomic ops)
|
|
*/
|
|
case BPF_STX | BPF_ATOMIC | BPF_W:
|
|
if (imm != BPF_ADD) {
|
|
pr_err_ratelimited("eBPF filter atomic op code %02x (@%d) unsupported\n",
|
|
code, i);
|
|
return -ENOTSUPP;
|
|
}
|
|
|
|
/* *(u32 *)(dst + off) += src */
|
|
|
|
bpf_set_seen_register(ctx, tmp_reg);
|
|
/* Get offset into TMP_REG */
|
|
EMIT(PPC_RAW_LI(tmp_reg, off));
|
|
/* load value from memory into r0 */
|
|
EMIT(PPC_RAW_LWARX(_R0, tmp_reg, dst_reg, 0));
|
|
/* add value from src_reg into this */
|
|
EMIT(PPC_RAW_ADD(_R0, _R0, src_reg));
|
|
/* store result back */
|
|
EMIT(PPC_RAW_STWCX(_R0, tmp_reg, dst_reg));
|
|
/* we're done if this succeeded */
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx - 3) * 4);
|
|
break;
|
|
|
|
case BPF_STX | BPF_ATOMIC | BPF_DW: /* *(u64 *)(dst + off) += src */
|
|
return -EOPNOTSUPP;
|
|
|
|
/*
|
|
* BPF_LDX
|
|
*/
|
|
case BPF_LDX | BPF_MEM | BPF_B: /* dst = *(u8 *)(ul) (src + off) */
|
|
case BPF_LDX | BPF_PROBE_MEM | BPF_B:
|
|
case BPF_LDX | BPF_MEM | BPF_H: /* dst = *(u16 *)(ul) (src + off) */
|
|
case BPF_LDX | BPF_PROBE_MEM | BPF_H:
|
|
case BPF_LDX | BPF_MEM | BPF_W: /* dst = *(u32 *)(ul) (src + off) */
|
|
case BPF_LDX | BPF_PROBE_MEM | BPF_W:
|
|
case BPF_LDX | BPF_MEM | BPF_DW: /* dst = *(u64 *)(ul) (src + off) */
|
|
case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
|
|
/*
|
|
* As PTR_TO_BTF_ID that uses BPF_PROBE_MEM mode could either be a valid
|
|
* kernel pointer or NULL but not a userspace address, execute BPF_PROBE_MEM
|
|
* load only if addr is kernel address (see is_kernel_addr()), otherwise
|
|
* set dst_reg=0 and move on.
|
|
*/
|
|
if (BPF_MODE(code) == BPF_PROBE_MEM) {
|
|
PPC_LI32(_R0, TASK_SIZE - off);
|
|
EMIT(PPC_RAW_CMPLW(src_reg, _R0));
|
|
PPC_BCC_SHORT(COND_GT, (ctx->idx + 4) * 4);
|
|
EMIT(PPC_RAW_LI(dst_reg, 0));
|
|
/*
|
|
* For BPF_DW case, "li reg_h,0" would be needed when
|
|
* !fp->aux->verifier_zext. Emit NOP otherwise.
|
|
*
|
|
* Note that "li reg_h,0" is emitted for BPF_B/H/W case,
|
|
* if necessary. So, jump there insted of emitting an
|
|
* additional "li reg_h,0" instruction.
|
|
*/
|
|
if (size == BPF_DW && !fp->aux->verifier_zext)
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
else
|
|
EMIT(PPC_RAW_NOP());
|
|
/*
|
|
* Need to jump two instructions instead of one for BPF_DW case
|
|
* as there are two load instructions for dst_reg_h & dst_reg
|
|
* respectively.
|
|
*/
|
|
if (size == BPF_DW)
|
|
PPC_JMP((ctx->idx + 3) * 4);
|
|
else
|
|
PPC_JMP((ctx->idx + 2) * 4);
|
|
}
|
|
|
|
switch (size) {
|
|
case BPF_B:
|
|
EMIT(PPC_RAW_LBZ(dst_reg, src_reg, off));
|
|
break;
|
|
case BPF_H:
|
|
EMIT(PPC_RAW_LHZ(dst_reg, src_reg, off));
|
|
break;
|
|
case BPF_W:
|
|
EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off));
|
|
break;
|
|
case BPF_DW:
|
|
EMIT(PPC_RAW_LWZ(dst_reg_h, src_reg, off));
|
|
EMIT(PPC_RAW_LWZ(dst_reg, src_reg, off + 4));
|
|
break;
|
|
}
|
|
|
|
if (size != BPF_DW && !fp->aux->verifier_zext)
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
|
|
if (BPF_MODE(code) == BPF_PROBE_MEM) {
|
|
int insn_idx = ctx->idx - 1;
|
|
int jmp_off = 4;
|
|
|
|
/*
|
|
* In case of BPF_DW, two lwz instructions are emitted, one
|
|
* for higher 32-bit and another for lower 32-bit. So, set
|
|
* ex->insn to the first of the two and jump over both
|
|
* instructions in fixup.
|
|
*
|
|
* Similarly, with !verifier_zext, two instructions are
|
|
* emitted for BPF_B/H/W case. So, set ex->insn to the
|
|
* instruction that could fault and skip over both
|
|
* instructions.
|
|
*/
|
|
if (size == BPF_DW || !fp->aux->verifier_zext) {
|
|
insn_idx -= 1;
|
|
jmp_off += 4;
|
|
}
|
|
|
|
ret = bpf_add_extable_entry(fp, image, pass, ctx, insn_idx,
|
|
jmp_off, dst_reg);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
break;
|
|
|
|
/*
|
|
* Doubleword load
|
|
* 16 byte instruction that uses two 'struct bpf_insn'
|
|
*/
|
|
case BPF_LD | BPF_IMM | BPF_DW: /* dst = (u64) imm */
|
|
tmp_idx = ctx->idx;
|
|
PPC_LI32(dst_reg_h, (u32)insn[i + 1].imm);
|
|
PPC_LI32(dst_reg, (u32)insn[i].imm);
|
|
/* padding to allow full 4 instructions for later patching */
|
|
for (j = ctx->idx - tmp_idx; j < 4; j++)
|
|
EMIT(PPC_RAW_NOP());
|
|
/* Adjust for two bpf instructions */
|
|
addrs[++i] = ctx->idx * 4;
|
|
break;
|
|
|
|
/*
|
|
* Return/Exit
|
|
*/
|
|
case BPF_JMP | BPF_EXIT:
|
|
/*
|
|
* If this isn't the very last instruction, branch to
|
|
* the epilogue. If we _are_ the last instruction,
|
|
* we'll just fall through to the epilogue.
|
|
*/
|
|
if (i != flen - 1) {
|
|
ret = bpf_jit_emit_exit_insn(image, ctx, _R0, exit_addr);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
/* else fall through to the epilogue */
|
|
break;
|
|
|
|
/*
|
|
* Call kernel helper or bpf function
|
|
*/
|
|
case BPF_JMP | BPF_CALL:
|
|
ctx->seen |= SEEN_FUNC;
|
|
|
|
ret = bpf_jit_get_func_addr(fp, &insn[i], false,
|
|
&func_addr, &func_addr_fixed);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
if (bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_5))) {
|
|
EMIT(PPC_RAW_STW(bpf_to_ppc(BPF_REG_5) - 1, _R1, 8));
|
|
EMIT(PPC_RAW_STW(bpf_to_ppc(BPF_REG_5), _R1, 12));
|
|
}
|
|
|
|
ret = bpf_jit_emit_func_call_rel(image, ctx, func_addr);
|
|
if (ret)
|
|
return ret;
|
|
|
|
EMIT(PPC_RAW_MR(bpf_to_ppc(BPF_REG_0) - 1, _R3));
|
|
EMIT(PPC_RAW_MR(bpf_to_ppc(BPF_REG_0), _R4));
|
|
break;
|
|
|
|
/*
|
|
* Jumps and branches
|
|
*/
|
|
case BPF_JMP | BPF_JA:
|
|
PPC_JMP(addrs[i + 1 + off]);
|
|
break;
|
|
|
|
case BPF_JMP | BPF_JGT | BPF_K:
|
|
case BPF_JMP | BPF_JGT | BPF_X:
|
|
case BPF_JMP | BPF_JSGT | BPF_K:
|
|
case BPF_JMP | BPF_JSGT | BPF_X:
|
|
case BPF_JMP32 | BPF_JGT | BPF_K:
|
|
case BPF_JMP32 | BPF_JGT | BPF_X:
|
|
case BPF_JMP32 | BPF_JSGT | BPF_K:
|
|
case BPF_JMP32 | BPF_JSGT | BPF_X:
|
|
true_cond = COND_GT;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JLT | BPF_K:
|
|
case BPF_JMP | BPF_JLT | BPF_X:
|
|
case BPF_JMP | BPF_JSLT | BPF_K:
|
|
case BPF_JMP | BPF_JSLT | BPF_X:
|
|
case BPF_JMP32 | BPF_JLT | BPF_K:
|
|
case BPF_JMP32 | BPF_JLT | BPF_X:
|
|
case BPF_JMP32 | BPF_JSLT | BPF_K:
|
|
case BPF_JMP32 | BPF_JSLT | BPF_X:
|
|
true_cond = COND_LT;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JGE | BPF_K:
|
|
case BPF_JMP | BPF_JGE | BPF_X:
|
|
case BPF_JMP | BPF_JSGE | BPF_K:
|
|
case BPF_JMP | BPF_JSGE | BPF_X:
|
|
case BPF_JMP32 | BPF_JGE | BPF_K:
|
|
case BPF_JMP32 | BPF_JGE | BPF_X:
|
|
case BPF_JMP32 | BPF_JSGE | BPF_K:
|
|
case BPF_JMP32 | BPF_JSGE | BPF_X:
|
|
true_cond = COND_GE;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JLE | BPF_K:
|
|
case BPF_JMP | BPF_JLE | BPF_X:
|
|
case BPF_JMP | BPF_JSLE | BPF_K:
|
|
case BPF_JMP | BPF_JSLE | BPF_X:
|
|
case BPF_JMP32 | BPF_JLE | BPF_K:
|
|
case BPF_JMP32 | BPF_JLE | BPF_X:
|
|
case BPF_JMP32 | BPF_JSLE | BPF_K:
|
|
case BPF_JMP32 | BPF_JSLE | BPF_X:
|
|
true_cond = COND_LE;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JEQ | BPF_K:
|
|
case BPF_JMP | BPF_JEQ | BPF_X:
|
|
case BPF_JMP32 | BPF_JEQ | BPF_K:
|
|
case BPF_JMP32 | BPF_JEQ | BPF_X:
|
|
true_cond = COND_EQ;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JNE | BPF_K:
|
|
case BPF_JMP | BPF_JNE | BPF_X:
|
|
case BPF_JMP32 | BPF_JNE | BPF_K:
|
|
case BPF_JMP32 | BPF_JNE | BPF_X:
|
|
true_cond = COND_NE;
|
|
goto cond_branch;
|
|
case BPF_JMP | BPF_JSET | BPF_K:
|
|
case BPF_JMP | BPF_JSET | BPF_X:
|
|
case BPF_JMP32 | BPF_JSET | BPF_K:
|
|
case BPF_JMP32 | BPF_JSET | BPF_X:
|
|
true_cond = COND_NE;
|
|
/* fallthrough; */
|
|
|
|
cond_branch:
|
|
switch (code) {
|
|
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_JEQ | BPF_X:
|
|
case BPF_JMP | BPF_JNE | BPF_X:
|
|
/* unsigned comparison */
|
|
EMIT(PPC_RAW_CMPLW(dst_reg_h, src_reg_h));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, src_reg));
|
|
break;
|
|
case BPF_JMP32 | BPF_JGT | BPF_X:
|
|
case BPF_JMP32 | BPF_JLT | BPF_X:
|
|
case BPF_JMP32 | BPF_JGE | BPF_X:
|
|
case BPF_JMP32 | BPF_JLE | BPF_X:
|
|
case BPF_JMP32 | BPF_JEQ | BPF_X:
|
|
case BPF_JMP32 | BPF_JNE | BPF_X:
|
|
/* unsigned comparison */
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, src_reg));
|
|
break;
|
|
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:
|
|
/* signed comparison */
|
|
EMIT(PPC_RAW_CMPW(dst_reg_h, src_reg_h));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, src_reg));
|
|
break;
|
|
case BPF_JMP32 | BPF_JSGT | BPF_X:
|
|
case BPF_JMP32 | BPF_JSLT | BPF_X:
|
|
case BPF_JMP32 | BPF_JSGE | BPF_X:
|
|
case BPF_JMP32 | BPF_JSLE | BPF_X:
|
|
/* signed comparison */
|
|
EMIT(PPC_RAW_CMPW(dst_reg, src_reg));
|
|
break;
|
|
case BPF_JMP | BPF_JSET | BPF_X:
|
|
EMIT(PPC_RAW_AND_DOT(_R0, dst_reg_h, src_reg_h));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_AND_DOT(_R0, dst_reg, src_reg));
|
|
break;
|
|
case BPF_JMP32 | BPF_JSET | BPF_X: {
|
|
EMIT(PPC_RAW_AND_DOT(_R0, dst_reg, src_reg));
|
|
break;
|
|
case BPF_JMP | BPF_JNE | BPF_K:
|
|
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:
|
|
/*
|
|
* Need sign-extended load, so only positive
|
|
* values can be used as imm in cmplwi
|
|
*/
|
|
if (imm >= 0 && imm < 32768) {
|
|
EMIT(PPC_RAW_CMPLWI(dst_reg_h, 0));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLWI(dst_reg, imm));
|
|
} else {
|
|
/* sign-extending load ... but unsigned comparison */
|
|
PPC_EX32(_R0, imm);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg_h, _R0));
|
|
PPC_LI32(_R0, imm);
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, _R0));
|
|
}
|
|
break;
|
|
case BPF_JMP32 | BPF_JNE | BPF_K:
|
|
case BPF_JMP32 | BPF_JEQ | BPF_K:
|
|
case BPF_JMP32 | BPF_JGT | BPF_K:
|
|
case BPF_JMP32 | BPF_JLT | BPF_K:
|
|
case BPF_JMP32 | BPF_JGE | BPF_K:
|
|
case BPF_JMP32 | BPF_JLE | BPF_K:
|
|
if (imm >= 0 && imm < 65536) {
|
|
EMIT(PPC_RAW_CMPLWI(dst_reg, imm));
|
|
} else {
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, _R0));
|
|
}
|
|
break;
|
|
}
|
|
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:
|
|
if (imm >= 0 && imm < 65536) {
|
|
EMIT(PPC_RAW_CMPWI(dst_reg_h, imm < 0 ? -1 : 0));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLWI(dst_reg, imm));
|
|
} else {
|
|
/* sign-extending load */
|
|
EMIT(PPC_RAW_CMPWI(dst_reg_h, imm < 0 ? -1 : 0));
|
|
PPC_LI32(_R0, imm);
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
EMIT(PPC_RAW_CMPLW(dst_reg, _R0));
|
|
}
|
|
break;
|
|
case BPF_JMP32 | BPF_JSGT | BPF_K:
|
|
case BPF_JMP32 | BPF_JSLT | BPF_K:
|
|
case BPF_JMP32 | BPF_JSGE | BPF_K:
|
|
case BPF_JMP32 | BPF_JSLE | BPF_K:
|
|
/*
|
|
* signed comparison, so any 16-bit value
|
|
* can be used in cmpwi
|
|
*/
|
|
if (imm >= -32768 && imm < 32768) {
|
|
EMIT(PPC_RAW_CMPWI(dst_reg, imm));
|
|
} else {
|
|
/* sign-extending load */
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_CMPW(dst_reg, _R0));
|
|
}
|
|
break;
|
|
case BPF_JMP | BPF_JSET | BPF_K:
|
|
/* andi does not sign-extend the immediate */
|
|
if (imm >= 0 && imm < 32768) {
|
|
/* PPC_ANDI is _only/always_ dot-form */
|
|
EMIT(PPC_RAW_ANDI(_R0, dst_reg, imm));
|
|
} else {
|
|
PPC_LI32(_R0, imm);
|
|
if (imm < 0) {
|
|
EMIT(PPC_RAW_CMPWI(dst_reg_h, 0));
|
|
PPC_BCC_SHORT(COND_NE, (ctx->idx + 2) * 4);
|
|
}
|
|
EMIT(PPC_RAW_AND_DOT(_R0, dst_reg, _R0));
|
|
}
|
|
break;
|
|
case BPF_JMP32 | BPF_JSET | BPF_K:
|
|
/* andi does not sign-extend the immediate */
|
|
if (imm >= 0 && imm < 32768) {
|
|
/* PPC_ANDI is _only/always_ dot-form */
|
|
EMIT(PPC_RAW_ANDI(_R0, dst_reg, imm));
|
|
} else {
|
|
PPC_LI32(_R0, imm);
|
|
EMIT(PPC_RAW_AND_DOT(_R0, dst_reg, _R0));
|
|
}
|
|
break;
|
|
}
|
|
PPC_BCC(true_cond, addrs[i + 1 + off]);
|
|
break;
|
|
|
|
/*
|
|
* Tail call
|
|
*/
|
|
case BPF_JMP | BPF_TAIL_CALL:
|
|
ctx->seen |= SEEN_TAILCALL;
|
|
ret = bpf_jit_emit_tail_call(image, ctx, addrs[i + 1]);
|
|
if (ret < 0)
|
|
return ret;
|
|
break;
|
|
|
|
default:
|
|
/*
|
|
* The filter contains something cruel & unusual.
|
|
* We don't handle it, but also there shouldn't be
|
|
* anything missing from our list.
|
|
*/
|
|
pr_err_ratelimited("eBPF filter opcode %04x (@%d) unsupported\n", code, i);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
if (BPF_CLASS(code) == BPF_ALU && !fp->aux->verifier_zext &&
|
|
!insn_is_zext(&insn[i + 1]) && !(BPF_OP(code) == BPF_END && imm == 64))
|
|
EMIT(PPC_RAW_LI(dst_reg_h, 0));
|
|
}
|
|
|
|
/* Set end-of-body-code address for exit. */
|
|
addrs[i] = ctx->idx * 4;
|
|
|
|
return 0;
|
|
}
|