diff options
Diffstat (limited to 'arch/powerpc/net')
| -rw-r--r-- | arch/powerpc/net/Makefile | 5 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit.h | 185 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp.c | 276 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp32.c | 1301 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp64.c | 1228 |
5 files changed, 2995 insertions, 0 deletions
diff --git a/arch/powerpc/net/Makefile b/arch/powerpc/net/Makefile new file mode 100644 index 0000000000..8e60af32e5 --- /dev/null +++ b/arch/powerpc/net/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Arch-specific network modules +# +obj-$(CONFIG_BPF_JIT) += bpf_jit_comp.o bpf_jit_comp$(BITS).o diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h new file mode 100644 index 0000000000..72b7bb34fa --- /dev/null +++ b/arch/powerpc/net/bpf_jit.h @@ -0,0 +1,185 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * bpf_jit.h: BPF JIT compiler for PPC + * + * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation + * 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> + */ +#ifndef _BPF_JIT_H +#define _BPF_JIT_H + +#ifndef __ASSEMBLY__ + +#include <asm/types.h> +#include <asm/ppc-opcode.h> + +#ifdef CONFIG_PPC64_ELF_ABI_V1 +#define FUNCTION_DESCR_SIZE 24 +#else +#define FUNCTION_DESCR_SIZE 0 +#endif + +#define CTX_NIA(ctx) ((unsigned long)ctx->idx * 4) + +#define PLANT_INSTR(d, idx, instr) \ + do { if (d) { (d)[idx] = instr; } idx++; } while (0) +#define EMIT(instr) PLANT_INSTR(image, ctx->idx, instr) + +/* Long jump; (unconditional 'branch') */ +#define PPC_JMP(dest) \ + do { \ + long offset = (long)(dest) - CTX_NIA(ctx); \ + if ((dest) != 0 && !is_offset_in_branch_range(offset)) { \ + pr_err_ratelimited("Branch offset 0x%lx (@%u) out of range\n", offset, ctx->idx); \ + return -ERANGE; \ + } \ + EMIT(PPC_RAW_BRANCH(offset)); \ + } while (0) + +/* bl (unconditional 'branch' with link) */ +#define PPC_BL(dest) EMIT(PPC_RAW_BL((dest) - (unsigned long)(image + ctx->idx))) + +/* "cond" here covers BO:BI fields. */ +#define PPC_BCC_SHORT(cond, dest) \ + do { \ + long offset = (long)(dest) - CTX_NIA(ctx); \ + if ((dest) != 0 && !is_offset_in_cond_branch_range(offset)) { \ + pr_err_ratelimited("Conditional branch offset 0x%lx (@%u) out of range\n", offset, ctx->idx); \ + return -ERANGE; \ + } \ + EMIT(PPC_INST_BRANCH_COND | (((cond) & 0x3ff) << 16) | (offset & 0xfffc)); \ + } while (0) + +/* Sign-extended 32-bit immediate load */ +#define PPC_LI32(d, i) do { \ + if ((int)(uintptr_t)(i) >= -32768 && \ + (int)(uintptr_t)(i) < 32768) \ + EMIT(PPC_RAW_LI(d, i)); \ + else { \ + EMIT(PPC_RAW_LIS(d, IMM_H(i))); \ + if (IMM_L(i)) \ + EMIT(PPC_RAW_ORI(d, d, IMM_L(i))); \ + } } while(0) + +#ifdef CONFIG_PPC64 +#define PPC_LI64(d, i) do { \ + if ((long)(i) >= -2147483648 && \ + (long)(i) < 2147483648) \ + PPC_LI32(d, i); \ + else { \ + if (!((uintptr_t)(i) & 0xffff800000000000ULL)) \ + EMIT(PPC_RAW_LI(d, ((uintptr_t)(i) >> 32) & \ + 0xffff)); \ + else { \ + EMIT(PPC_RAW_LIS(d, ((uintptr_t)(i) >> 48))); \ + if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \ + EMIT(PPC_RAW_ORI(d, d, \ + ((uintptr_t)(i) >> 32) & 0xffff)); \ + } \ + EMIT(PPC_RAW_SLDI(d, d, 32)); \ + if ((uintptr_t)(i) & 0x00000000ffff0000ULL) \ + EMIT(PPC_RAW_ORIS(d, d, \ + ((uintptr_t)(i) >> 16) & 0xffff)); \ + if ((uintptr_t)(i) & 0x000000000000ffffULL) \ + EMIT(PPC_RAW_ORI(d, d, (uintptr_t)(i) & \ + 0xffff)); \ + } } while (0) +#endif + +/* + * The fly in the ointment of code size changing from pass to pass is + * avoided by padding the short branch case with a NOP. If code size differs + * with different branch reaches we will have the issue of code moving from + * one pass to the next and will need a few passes to converge on a stable + * state. + */ +#define PPC_BCC(cond, dest) do { \ + if (is_offset_in_cond_branch_range((long)(dest) - CTX_NIA(ctx))) { \ + PPC_BCC_SHORT(cond, dest); \ + EMIT(PPC_RAW_NOP()); \ + } else { \ + /* Flip the 'T or F' bit to invert comparison */ \ + PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, CTX_NIA(ctx) + 2*4); \ + PPC_JMP(dest); \ + } } while(0) + +/* To create a branch condition, select a bit of cr0... */ +#define CR0_LT 0 +#define CR0_GT 1 +#define CR0_EQ 2 +/* ...and modify BO[3] */ +#define COND_CMP_TRUE 0x100 +#define COND_CMP_FALSE 0x000 +/* Together, they make all required comparisons: */ +#define COND_GT (CR0_GT | COND_CMP_TRUE) +#define COND_GE (CR0_LT | COND_CMP_FALSE) +#define COND_EQ (CR0_EQ | COND_CMP_TRUE) +#define COND_NE (CR0_EQ | COND_CMP_FALSE) +#define COND_LT (CR0_LT | COND_CMP_TRUE) +#define COND_LE (CR0_GT | COND_CMP_FALSE) + +#define SEEN_FUNC 0x20000000 /* might call external helpers */ +#define SEEN_TAILCALL 0x40000000 /* uses tail calls */ + +struct codegen_context { + /* + * This is used to track register usage as well + * as calls to external helpers. + * - register usage is tracked with corresponding + * bits (r3-r31) + * - rest of the bits can be used to track other + * things -- for now, we use bits 0 to 2 + * encoded in SEEN_* macros above + */ + unsigned int seen; + unsigned int idx; + unsigned int stack_size; + int b2p[MAX_BPF_JIT_REG + 2]; + unsigned int exentry_idx; + unsigned int alt_exit_addr; +}; + +#define bpf_to_ppc(r) (ctx->b2p[r]) + +#ifdef CONFIG_PPC32 +#define BPF_FIXUP_LEN 3 /* Three instructions => 12 bytes */ +#else +#define BPF_FIXUP_LEN 2 /* Two instructions => 8 bytes */ +#endif + +static inline void bpf_flush_icache(void *start, void *end) +{ + smp_wmb(); /* smp write barrier */ + flush_icache_range((unsigned long)start, (unsigned long)end); +} + +static inline bool bpf_is_seen_register(struct codegen_context *ctx, int i) +{ + return ctx->seen & (1 << (31 - i)); +} + +static inline void bpf_set_seen_register(struct codegen_context *ctx, int i) +{ + ctx->seen |= 1 << (31 - i); +} + +static inline void bpf_clear_seen_register(struct codegen_context *ctx, int i) +{ + ctx->seen &= ~(1 << (31 - i)); +} + +void bpf_jit_init_reg_mapping(struct codegen_context *ctx); +int bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func); +int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx, + u32 *addrs, int pass, bool extra_pass); +void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx); +void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx); +void bpf_jit_realloc_regs(struct codegen_context *ctx); +int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx, int tmp_reg, long exit_addr); + +int bpf_add_extable_entry(struct bpf_prog *fp, u32 *image, int pass, struct codegen_context *ctx, + int insn_idx, int jmp_off, int dst_reg); + +#endif + +#endif diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c new file mode 100644 index 0000000000..37043dfc1a --- /dev/null +++ b/arch/powerpc/net/bpf_jit_comp.c @@ -0,0 +1,276 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * eBPF JIT compiler + * + * Copyright 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> + * IBM Corporation + * + * Based on the powerpc classic BPF JIT compiler by Matt Evans + */ +#include <linux/moduleloader.h> +#include <asm/cacheflush.h> +#include <asm/asm-compat.h> +#include <linux/netdevice.h> +#include <linux/filter.h> +#include <linux/if_vlan.h> +#include <asm/kprobes.h> +#include <linux/bpf.h> + +#include "bpf_jit.h" + +static void bpf_jit_fill_ill_insns(void *area, unsigned int size) +{ + memset32(area, BREAKPOINT_INSTRUCTION, size / 4); +} + +int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx, int tmp_reg, long exit_addr) +{ + if (!exit_addr || is_offset_in_branch_range(exit_addr - (ctx->idx * 4))) { + PPC_JMP(exit_addr); + } else if (ctx->alt_exit_addr) { + if (WARN_ON(!is_offset_in_branch_range((long)ctx->alt_exit_addr - (ctx->idx * 4)))) + return -1; + PPC_JMP(ctx->alt_exit_addr); + } else { + ctx->alt_exit_addr = ctx->idx * 4; + bpf_jit_build_epilogue(image, ctx); + } + + return 0; +} + +struct powerpc64_jit_data { + struct bpf_binary_header *header; + u32 *addrs; + u8 *image; + u32 proglen; + struct codegen_context ctx; +}; + +bool bpf_jit_needs_zext(void) +{ + return true; +} + +struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) +{ + u32 proglen; + u32 alloclen; + u8 *image = NULL; + u32 *code_base; + u32 *addrs; + struct powerpc64_jit_data *jit_data; + struct codegen_context cgctx; + int pass; + int flen; + struct bpf_binary_header *bpf_hdr; + struct bpf_prog *org_fp = fp; + struct bpf_prog *tmp_fp; + bool bpf_blinded = false; + bool extra_pass = false; + u32 extable_len; + u32 fixup_len; + + if (!fp->jit_requested) + return org_fp; + + tmp_fp = bpf_jit_blind_constants(org_fp); + if (IS_ERR(tmp_fp)) + return org_fp; + + if (tmp_fp != org_fp) { + bpf_blinded = true; + fp = tmp_fp; + } + + jit_data = fp->aux->jit_data; + if (!jit_data) { + jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL); + if (!jit_data) { + fp = org_fp; + goto out; + } + fp->aux->jit_data = jit_data; + } + + flen = fp->len; + addrs = jit_data->addrs; + if (addrs) { + cgctx = jit_data->ctx; + image = jit_data->image; + bpf_hdr = jit_data->header; + proglen = jit_data->proglen; + extra_pass = true; + /* During extra pass, ensure index is reset before repopulating extable entries */ + cgctx.exentry_idx = 0; + goto skip_init_ctx; + } + + addrs = kcalloc(flen + 1, sizeof(*addrs), GFP_KERNEL); + if (addrs == NULL) { + fp = org_fp; + goto out_addrs; + } + + memset(&cgctx, 0, sizeof(struct codegen_context)); + bpf_jit_init_reg_mapping(&cgctx); + + /* Make sure that the stack is quadword aligned. */ + cgctx.stack_size = round_up(fp->aux->stack_depth, 16); + + /* Scouting faux-generate pass 0 */ + if (bpf_jit_build_body(fp, 0, &cgctx, addrs, 0, false)) { + /* We hit something illegal or unsupported. */ + fp = org_fp; + goto out_addrs; + } + + /* + * If we have seen a tail call, we need a second pass. + * This is because bpf_jit_emit_common_epilogue() is called + * from bpf_jit_emit_tail_call() with a not yet stable ctx->seen. + * We also need a second pass if we ended up with too large + * a program so as to ensure BPF_EXIT branches are in range. + */ + if (cgctx.seen & SEEN_TAILCALL || !is_offset_in_branch_range((long)cgctx.idx * 4)) { + cgctx.idx = 0; + if (bpf_jit_build_body(fp, 0, &cgctx, addrs, 0, false)) { + fp = org_fp; + goto out_addrs; + } + } + + bpf_jit_realloc_regs(&cgctx); + /* + * Pretend to build prologue, given the features we've seen. This will + * update ctgtx.idx as it pretends to output instructions, then we can + * calculate total size from idx. + */ + bpf_jit_build_prologue(0, &cgctx); + addrs[fp->len] = cgctx.idx * 4; + bpf_jit_build_epilogue(0, &cgctx); + + fixup_len = fp->aux->num_exentries * BPF_FIXUP_LEN * 4; + extable_len = fp->aux->num_exentries * sizeof(struct exception_table_entry); + + proglen = cgctx.idx * 4; + alloclen = proglen + FUNCTION_DESCR_SIZE + fixup_len + extable_len; + + bpf_hdr = bpf_jit_binary_alloc(alloclen, &image, 4, bpf_jit_fill_ill_insns); + if (!bpf_hdr) { + fp = org_fp; + goto out_addrs; + } + + if (extable_len) + fp->aux->extable = (void *)image + FUNCTION_DESCR_SIZE + proglen + fixup_len; + +skip_init_ctx: + code_base = (u32 *)(image + FUNCTION_DESCR_SIZE); + + /* Code generation passes 1-2 */ + for (pass = 1; pass < 3; pass++) { + /* Now build the prologue, body code & epilogue for real. */ + cgctx.idx = 0; + cgctx.alt_exit_addr = 0; + bpf_jit_build_prologue(code_base, &cgctx); + if (bpf_jit_build_body(fp, code_base, &cgctx, addrs, pass, extra_pass)) { + bpf_jit_binary_free(bpf_hdr); + fp = org_fp; + goto out_addrs; + } + bpf_jit_build_epilogue(code_base, &cgctx); + + if (bpf_jit_enable > 1) + pr_info("Pass %d: shrink = %d, seen = 0x%x\n", pass, + proglen - (cgctx.idx * 4), cgctx.seen); + } + + if (bpf_jit_enable > 1) + /* + * Note that we output the base address of the code_base + * rather than image, since opcodes are in code_base. + */ + bpf_jit_dump(flen, proglen, pass, code_base); + +#ifdef CONFIG_PPC64_ELF_ABI_V1 + /* Function descriptor nastiness: Address + TOC */ + ((u64 *)image)[0] = (u64)code_base; + ((u64 *)image)[1] = local_paca->kernel_toc; +#endif + + fp->bpf_func = (void *)image; + fp->jited = 1; + fp->jited_len = proglen + FUNCTION_DESCR_SIZE; + + bpf_flush_icache(bpf_hdr, (u8 *)bpf_hdr + bpf_hdr->size); + if (!fp->is_func || extra_pass) { + bpf_jit_binary_lock_ro(bpf_hdr); + bpf_prog_fill_jited_linfo(fp, addrs); +out_addrs: + kfree(addrs); + kfree(jit_data); + fp->aux->jit_data = NULL; + } else { + jit_data->addrs = addrs; + jit_data->ctx = cgctx; + jit_data->proglen = proglen; + jit_data->image = image; + jit_data->header = bpf_hdr; + } + +out: + if (bpf_blinded) + bpf_jit_prog_release_other(fp, fp == org_fp ? tmp_fp : org_fp); + + return fp; +} + +/* + * The caller should check for (BPF_MODE(code) == BPF_PROBE_MEM) before calling + * this function, as this only applies to BPF_PROBE_MEM, for now. + */ +int bpf_add_extable_entry(struct bpf_prog *fp, u32 *image, int pass, struct codegen_context *ctx, + int insn_idx, int jmp_off, int dst_reg) +{ + off_t offset; + unsigned long pc; + struct exception_table_entry *ex; + u32 *fixup; + + /* Populate extable entries only in the last pass */ + if (pass != 2) + return 0; + + if (!fp->aux->extable || + WARN_ON_ONCE(ctx->exentry_idx >= fp->aux->num_exentries)) + return -EINVAL; + + pc = (unsigned long)&image[insn_idx]; + + fixup = (void *)fp->aux->extable - + (fp->aux->num_exentries * BPF_FIXUP_LEN * 4) + + (ctx->exentry_idx * BPF_FIXUP_LEN * 4); + + fixup[0] = PPC_RAW_LI(dst_reg, 0); + if (IS_ENABLED(CONFIG_PPC32)) + fixup[1] = PPC_RAW_LI(dst_reg - 1, 0); /* clear higher 32-bit register too */ + + fixup[BPF_FIXUP_LEN - 1] = + PPC_RAW_BRANCH((long)(pc + jmp_off) - (long)&fixup[BPF_FIXUP_LEN - 1]); + + ex = &fp->aux->extable[ctx->exentry_idx]; + + offset = pc - (long)&ex->insn; + if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN)) + return -ERANGE; + ex->insn = offset; + + offset = (long)fixup - (long)&ex->fixup; + if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN)) + return -ERANGE; + ex->fixup = offset; + + ctx->exentry_idx++; + return 0; +} diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c new file mode 100644 index 0000000000..7f91ea064c --- /dev/null +++ b/arch/powerpc/net/bpf_jit_comp32.c @@ -0,0 +1,1301 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * eBPF JIT compiler for PPC32 + * + * Copyright 2020 Christophe Leroy <christophe.leroy@csgroup.eu> + * CS GROUP France + * + * Based on PPC64 eBPF JIT compiler by Naveen N. Rao + */ +#include <linux/moduleloader.h> +#include <asm/cacheflush.h> +#include <asm/asm-compat.h> +#include <linux/netdevice.h> +#include <linux/filter.h> +#include <linux/if_vlan.h> +#include <asm/kprobes.h> +#include <linux/bpf.h> + +#include "bpf_jit.h" + +/* + * Stack layout: + * + * [ prev sp ] <------------- + * [ nv gpr save area ] 16 * 4 | + * fp (r31) --> [ ebpf stack space ] upto 512 | + * [ frame header ] 16 | + * sp (r1) ---> [ stack pointer ] -------------- + */ + +/* for gpr non volatile registers r17 to r31 (14) + tail call */ +#define BPF_PPC_STACK_SAVE (15 * 4 + 4) +/* stack frame, ensure this is quadword aligned */ +#define BPF_PPC_STACKFRAME(ctx) (STACK_FRAME_MIN_SIZE + BPF_PPC_STACK_SAVE + (ctx)->stack_size) + +#define PPC_EX32(r, i) EMIT(PPC_RAW_LI((r), (i) < 0 ? -1 : 0)) + +/* PPC NVR range -- update this if we ever use NVRs below r17 */ +#define BPF_PPC_NVR_MIN _R17 +#define BPF_PPC_TC _R16 + +/* BPF register usage */ +#define TMP_REG (MAX_BPF_JIT_REG + 0) + +/* BPF to ppc register mappings */ +void bpf_jit_init_reg_mapping(struct codegen_context *ctx) +{ + /* function return value */ + ctx->b2p[BPF_REG_0] = _R12; + /* function arguments */ + ctx->b2p[BPF_REG_1] = _R4; + ctx->b2p[BPF_REG_2] = _R6; + ctx->b2p[BPF_REG_3] = _R8; + ctx->b2p[BPF_REG_4] = _R10; + ctx->b2p[BPF_REG_5] = _R22; + /* non volatile registers */ + ctx->b2p[BPF_REG_6] = _R24; + ctx->b2p[BPF_REG_7] = _R26; + ctx->b2p[BPF_REG_8] = _R28; + ctx->b2p[BPF_REG_9] = _R30; + /* frame pointer aka BPF_REG_10 */ + ctx->b2p[BPF_REG_FP] = _R18; + /* eBPF jit internal registers */ + ctx->b2p[BPF_REG_AX] = _R20; + ctx->b2p[TMP_REG] = _R31; /* 32 bits */ +} + +static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg) +{ + if ((reg >= BPF_PPC_NVR_MIN && reg < 32) || reg == BPF_PPC_TC) + return BPF_PPC_STACKFRAME(ctx) - 4 * (32 - reg); + + WARN(true, "BPF JIT is asking about unknown registers, will crash the stack"); + /* Use the hole we have left for alignment */ + return BPF_PPC_STACKFRAME(ctx) - 4; +} + +#define SEEN_VREG_MASK 0x1ff80000 /* Volatile registers r3-r12 */ +#define SEEN_NVREG_FULL_MASK 0x0003ffff /* Non volatile registers r14-r31 */ +#define SEEN_NVREG_TEMP_MASK 0x00001e01 /* BPF_REG_5, BPF_REG_AX, TMP_REG */ + +static inline bool bpf_has_stack_frame(struct codegen_context *ctx) +{ + /* + * We only need a stack frame if: + * - we call other functions (kernel helpers), or + * - we use non volatile registers, or + * - we use tail call counter + * - the bpf program uses its stack area + * The latter condition is deduced from the usage of BPF_REG_FP + */ + return ctx->seen & (SEEN_FUNC | SEEN_TAILCALL | SEEN_NVREG_FULL_MASK) || + bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_FP)); +} + +void bpf_jit_realloc_regs(struct codegen_context *ctx) +{ + unsigned int nvreg_mask; + + if (ctx->seen & SEEN_FUNC) + nvreg_mask = SEEN_NVREG_TEMP_MASK; + else + nvreg_mask = SEEN_NVREG_FULL_MASK; + + while (ctx->seen & nvreg_mask && + (ctx->seen & SEEN_VREG_MASK) != SEEN_VREG_MASK) { + int old = 32 - fls(ctx->seen & (nvreg_mask & 0xaaaaaaab)); + int new = 32 - fls(~ctx->seen & (SEEN_VREG_MASK & 0xaaaaaaaa)); + int i; + + for (i = BPF_REG_0; i <= TMP_REG; i++) { + if (ctx->b2p[i] != old) + continue; + ctx->b2p[i] = new; + bpf_set_seen_register(ctx, new); + bpf_clear_seen_register(ctx, old); + if (i != TMP_REG) { + bpf_set_seen_register(ctx, new - 1); + bpf_clear_seen_register(ctx, old - 1); + } + break; + } + } +} + +void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx) +{ + int i; + + /* Initialize tail_call_cnt, to be skipped if we do tail calls. */ + if (ctx->seen & SEEN_TAILCALL) + EMIT(PPC_RAW_LI(_R4, 0)); + else + EMIT(PPC_RAW_NOP()); + +#define BPF_TAILCALL_PROLOGUE_SIZE 4 + + if (bpf_has_stack_frame(ctx)) + EMIT(PPC_RAW_STWU(_R1, _R1, -BPF_PPC_STACKFRAME(ctx))); + + if (ctx->seen & SEEN_TAILCALL) + EMIT(PPC_RAW_STW(_R4, _R1, bpf_jit_stack_offsetof(ctx, BPF_PPC_TC))); + + /* First arg comes in as a 32 bits pointer. */ + EMIT(PPC_RAW_MR(bpf_to_ppc(BPF_REG_1), _R3)); + EMIT(PPC_RAW_LI(bpf_to_ppc(BPF_REG_1) - 1, 0)); + + /* + * We need a stack frame, but we don't necessarily need to + * save/restore LR unless we call other functions + */ + if (ctx->seen & SEEN_FUNC) + EMIT(PPC_RAW_MFLR(_R0)); + + /* + * Back up non-volatile regs -- registers r18-r31 + */ + for (i = BPF_PPC_NVR_MIN; i <= 31; i++) + if (bpf_is_seen_register(ctx, i)) + EMIT(PPC_RAW_STW(i, _R1, bpf_jit_stack_offsetof(ctx, i))); + + /* Setup frame pointer to point to the bpf stack area */ + if (bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_FP))) { + EMIT(PPC_RAW_LI(bpf_to_ppc(BPF_REG_FP) - 1, 0)); + EMIT(PPC_RAW_ADDI(bpf_to_ppc(BPF_REG_FP), _R1, + STACK_FRAME_MIN_SIZE + ctx->stack_size)); + } + + if (ctx->seen & SEEN_FUNC) + EMIT(PPC_RAW_STW(_R0, _R1, BPF_PPC_STACKFRAME(ctx) + PPC_LR_STKOFF)); +} + +static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx) +{ + int i; + + /* Restore NVRs */ + for (i = BPF_PPC_NVR_MIN; i <= 31; i++) + if (bpf_is_seen_register(ctx, i)) + EMIT(PPC_RAW_LWZ(i, _R1, bpf_jit_stack_offsetof(ctx, i))); + + if (ctx->seen & SEEN_FUNC) + EMIT(PPC_RAW_LWZ(_R0, _R1, BPF_PPC_STACKFRAME(ctx) + PPC_LR_STKOFF)); + + /* Tear down our stack frame */ + if (bpf_has_stack_frame(ctx)) + EMIT(PPC_RAW_ADDI(_R1, _R1, BPF_PPC_STACKFRAME(ctx))); + + if (ctx->seen & SEEN_FUNC) + EMIT(PPC_RAW_MTLR(_R0)); + +} + +void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx) +{ + EMIT(PPC_RAW_MR(_R3, bpf_to_ppc(BPF_REG_0))); + + bpf_jit_emit_common_epilogue(image, ctx); + + EMIT(PPC_RAW_BLR()); +} + +int bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func) +{ + s32 rel = (s32)func - (s32)(image + ctx->idx); + + if (image && rel < 0x2000000 && rel >= -0x2000000) { + PPC_BL(func); + } else { + /* Load function address into r0 */ + EMIT(PPC_RAW_LIS(_R0, IMM_H(func))); + EMIT(PPC_RAW_ORI(_R0, _R0, IMM_L(func))); + EMIT(PPC_RAW_MTCTR(_R0)); + EMIT(PPC_RAW_BCTRL()); + } + + return 0; +} + +static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 out) +{ + /* + * By now, the eBPF program has already setup parameters in r3-r6 + * r3-r4/BPF_REG_1 - pointer to ctx -- passed as is to the next bpf program + * r5-r6/BPF_REG_2 - pointer to bpf_array + * r7-r8/BPF_REG_3 - index in bpf_array + */ + int b2p_bpf_array = bpf_to_ppc(BPF_REG_2); + int b2p_index = bpf_to_ppc(BPF_REG_3); + + /* + * if (index >= array->map.max_entries) + * goto out; + */ + EMIT(PPC_RAW_LWZ(_R0, b2p_bpf_array, offsetof(struct bpf_array, map.max_entries))); + EMIT(PPC_RAW_CMPLW(b2p_index, _R0)); + EMIT(PPC_RAW_LWZ(_R0, _R1, bpf_jit_stack_offsetof(ctx, BPF_PPC_TC))); + PPC_BCC_SHORT(COND_GE, out); + + /* + * if (tail_call_cnt >= MAX_TAIL_CALL_CNT) + * goto out; + */ + EMIT(PPC_RAW_CMPLWI(_R0, MAX_TAIL_CALL_CNT)); + /* tail_call_cnt++; */ + EMIT(PPC_RAW_ADDIC(_R0, _R0, 1)); + PPC_BCC_SHORT(COND_GE, out); + + /* prog = array->ptrs[index]; */ + EMIT(PPC_RAW_RLWINM(_R3, b2p_index, 2, 0, 29)); + EMIT(PPC_RAW_ADD(_R3, _R3, b2p_bpf_array)); + EMIT(PPC_RAW_LWZ(_R3, _R3, offsetof(struct bpf_array, ptrs))); + + /* + * if (prog == NULL) + * goto out; + */ + EMIT(PPC_RAW_CMPLWI(_R3, 0)); + PPC_BCC_SHORT(COND_EQ, out); + + /* goto *(prog->bpf_func + prologue_size); */ + EMIT(PPC_RAW_LWZ(_R3, _R3, offsetof(struct bpf_prog, bpf_func))); + EMIT(PPC_RAW_ADDIC(_R3, _R3, BPF_TAILCALL_PROLOGUE_SIZE)); + EMIT(PPC_RAW_MTCTR(_R3)); + + EMIT(PPC_RAW_MR(_R3, bpf_to_ppc(BPF_REG_1))); + + /* Put tail_call_cnt in r4 */ + EMIT(PPC_RAW_MR(_R4, _R0)); + + /* tear restore NVRs, ... */ + bpf_jit_emit_common_epilogue(image, ctx); + + EMIT(PPC_RAW_BCTR()); + + /* out: */ + return 0; +} + +/* Assemble the body code between the prologue & epilogue */ +int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx, + u32 *addrs, int pass, bool extra_pass) +{ + const struct bpf_insn *insn = fp->insnsi; + int flen = fp->len; + int i, ret; + + /* Start of epilogue code - will only be valid 2nd pass onwards */ + u32 exit_addr = addrs[flen]; + + for (i = 0; i < flen; i++) { + u32 code = insn[i].code; + u32 prevcode = i ? insn[i - 1].code : 0; + u32 dst_reg = bpf_to_ppc(insn[i].dst_reg); + u32 dst_reg_h = dst_reg - 1; + u32 src_reg = bpf_to_ppc(insn[i].src_reg); + u32 src_reg_h = src_reg - 1; + u32 src2_reg = dst_reg; + u32 src2_reg_h = dst_reg_h; + u32 ax_reg = bpf_to_ppc(BPF_REG_AX); + u32 tmp_reg = bpf_to_ppc(TMP_REG); + u32 size = BPF_SIZE(code); + u32 save_reg, ret_reg; + s16 off = insn[i].off; + s32 imm = insn[i].imm; + bool func_addr_fixed; + u64 func_addr; + u32 true_cond; + u32 tmp_idx; + int j; + + if (i && (BPF_CLASS(code) == BPF_ALU64 || BPF_CLASS(code) == BPF_ALU) && + (BPF_CLASS(prevcode) == BPF_ALU64 || BPF_CLASS(prevcode) == BPF_ALU) && + BPF_OP(prevcode) == BPF_MOV && BPF_SRC(prevcode) == BPF_X && + insn[i - 1].dst_reg == insn[i].dst_reg && insn[i - 1].imm != 1) { + src2_reg = bpf_to_ppc(insn[i - 1].src_reg); + src2_reg_h = src2_reg - 1; + ctx->idx = addrs[i - 1] / 4; + } + + /* + * addrs[] maps a BPF bytecode address into a real offset from + * the start of the body code. + */ + addrs[i] = ctx->idx * 4; + + /* + * As an optimization, we note down which registers + * are used so that we can only save/restore those in our + * prologue and epilogue. We do this here regardless of whether + * the actual BPF instruction uses src/dst registers or not + * (for instance, BPF_CALL does not use them). The expectation + * is that those instructions will have src_reg/dst_reg set to + * 0. Even otherwise, we just lose some prologue/epilogue + * optimization but everything else should work without + * any issues. + */ + if (dst_reg >= 3 && dst_reg < 32) { + bpf_set_seen_register(ctx, dst_reg); + bpf_set_seen_register(ctx, dst_reg_h); + } + + if (src_reg >= 3 && src_reg < 32) { + bpf_set_seen_register(ctx, src_reg); + bpf_set_seen_register(ctx, src_reg_h); + } + + switch (code) { + /* + * Arithmetic operations: ADD/SUB/MUL/DIV/MOD/NEG + */ + case BPF_ALU | BPF_ADD | BPF_X: /* (u32) dst += (u32) src */ + EMIT(PPC_RAW_ADD(dst_reg, src2_reg, src_reg)); + break; + case BPF_ALU64 | BPF_ADD | BPF_X: /* dst += src */ + EMIT(PPC_RAW_ADDC(dst_reg, src2_reg, src_reg)); + EMIT(PPC_RAW_ADDE(dst_reg_h, src2_reg_h, src_reg_h)); + break; + case BPF_ALU | BPF_SUB | BPF_X: /* (u32) dst -= (u32) src */ + EMIT(PPC_RAW_SUB(dst_reg, src2_reg, src_reg)); + break; + case BPF_ALU64 | BPF_SUB | BPF_X: /* dst -= src */ + EMIT(PPC_RAW_SUBFC(dst_reg, src_reg, src2_reg)); + EMIT(PPC_RAW_SUBFE(dst_reg_h, src_reg_h, src2_reg_h)); + break; + case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */ + imm = -imm; + fallthrough; + case BPF_ALU | BPF_ADD | BPF_K: /* (u32) dst += (u32) imm */ + if (!imm) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + } else if (IMM_HA(imm) & 0xffff) { + EMIT(PPC_RAW_ADDIS(dst_reg, src2_reg, IMM_HA(imm))); + src2_reg = dst_reg; + } + if (IMM_L(imm)) + EMIT(PPC_RAW_ADDI(dst_reg, src2_reg, IMM_L(imm))); + break; + case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */ + imm = -imm; + fallthrough; + case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */ + if (!imm) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src2_reg_h)); + break; + } + if (imm >= -32768 && imm < 32768) { + EMIT(PPC_RAW_ADDIC(dst_reg, src2_reg, imm)); + } else { + PPC_LI32(_R0, imm); + EMIT(PPC_RAW_ADDC(dst_reg, src2_reg, _R0)); + } + if (imm >= 0 || (BPF_OP(code) == BPF_SUB && imm == 0x80000000)) + EMIT(PPC_RAW_ADDZE(dst_reg_h, src2_reg_h)); + else + EMIT(PPC_RAW_ADDME(dst_reg_h, src2_reg_h)); + break; + case BPF_ALU64 | BPF_MUL | BPF_X: /* dst *= src */ + bpf_set_seen_register(ctx, tmp_reg); + EMIT(PPC_RAW_MULW(_R0, src2_reg, src_reg_h)); + EMIT(PPC_RAW_MULW(dst_reg_h, src2_reg_h, src_reg)); + EMIT(PPC_RAW_MULHWU(tmp_reg, src2_reg, src_reg)); + EMIT(PPC_RAW_MULW(dst_reg, src2_reg, src_reg)); + EMIT(PPC_RAW_ADD(dst_reg_h, dst_reg_h, _R0)); + EMIT(PPC_RAW_ADD(dst_reg_h, dst_reg_h, tmp_reg)); + break; + case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */ + EMIT(PPC_RAW_MULW(dst_reg, src2_reg, src_reg)); + break; + case BPF_ALU | BPF_MUL | BPF_K: /* (u32) dst *= (u32) imm */ + if (imm == 1) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + } else if (imm == -1) { + EMIT(PPC_RAW_SUBFIC(dst_reg, src2_reg, 0)); + } else if (is_power_of_2((u32)imm)) { + EMIT(PPC_RAW_SLWI(dst_reg, src2_reg, ilog2(imm))); + } else if (imm >= -32768 && imm < 32768) { + EMIT(PPC_RAW_MULI(dst_reg, src2_reg, imm)); + } else { + PPC_LI32(_R0, imm); + EMIT(PPC_RAW_MULW(dst_reg, src2_reg, _R0)); + } + break; + case BPF_ALU64 | BPF_MUL | BPF_K: /* dst *= imm */ + if (!imm) { + PPC_LI32(dst_reg, 0); + PPC_LI32(dst_reg_h, 0); + } else if (imm == 1) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src2_reg_h)); + } else if (imm == -1) { + EMIT(PPC_RAW_SUBFIC(dst_reg, src2_reg, 0)); + EMIT(PPC_RAW_SUBFZE(dst_reg_h, src2_reg_h)); + } else if (imm > 0 && is_power_of_2(imm)) { + imm = ilog2(imm); + EMIT(PPC_RAW_RLWINM(dst_reg_h, src2_reg_h, imm, 0, 31 - imm)); + EMIT(PPC_RAW_RLWIMI(dst_reg_h, dst_reg, imm, 32 - imm, 31)); + EMIT(PPC_RAW_SLWI(dst_reg, src2_reg, imm)); + } else { + bpf_set_seen_register(ctx, tmp_reg); + PPC_LI32(tmp_reg, imm); + EMIT(PPC_RAW_MULW(dst_reg_h, src2_reg_h, tmp_reg)); + if (imm < 0) + EMIT(PPC_RAW_SUB(dst_reg_h, dst_reg_h, src2_reg)); + EMIT(PPC_RAW_MULHWU(_R0, src2_reg, tmp_reg)); + EMIT(PPC_RAW_MULW(dst_reg, src2_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, src2_reg, src_reg)); + break; + case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */ + EMIT(PPC_RAW_DIVWU(_R0, src2_reg, src_reg)); + EMIT(PPC_RAW_MULW(_R0, src_reg, _R0)); + EMIT(PPC_RAW_SUB(dst_reg, src2_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) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + } else if (is_power_of_2((u32)imm)) { + EMIT(PPC_RAW_SRWI(dst_reg, src2_reg, ilog2(imm))); + } else { + PPC_LI32(_R0, imm); + EMIT(PPC_RAW_DIVWU(dst_reg, src2_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, src2_reg, tmp_reg)); + EMIT(PPC_RAW_MULW(_R0, tmp_reg, _R0)); + EMIT(PPC_RAW_SUB(dst_reg, src2_reg, _R0)); + } else if (imm == 1) { + EMIT(PPC_RAW_LI(dst_reg, 0)); + } else { + imm = ilog2((u32)imm); + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 0, 32 - 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, src2_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, src2_reg, 0)); + EMIT(PPC_RAW_SUBFZE(dst_reg_h, src2_reg_h)); + imm = -imm; + src2_reg = dst_reg; + } + if (imm == 1) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src2_reg_h)); + } else { + imm = ilog2(imm); + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 32 - imm, imm, 31)); + EMIT(PPC_RAW_RLWIMI(dst_reg, src2_reg_h, 32 - imm, 0, imm - 1)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, src2_reg_h, imm)); + } + break; + case BPF_ALU | BPF_NEG: /* (u32) dst = -dst */ + EMIT(PPC_RAW_NEG(dst_reg, src2_reg)); + break; + case BPF_ALU64 | BPF_NEG: /* dst = -dst */ + EMIT(PPC_RAW_SUBFIC(dst_reg, src2_reg, 0)); + EMIT(PPC_RAW_SUBFZE(dst_reg_h, src2_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, src2_reg, src_reg)); + EMIT(PPC_RAW_AND(dst_reg_h, src2_reg_h, src_reg_h)); + break; + case BPF_ALU | BPF_AND | BPF_X: /* (u32) dst = dst & src */ + EMIT(PPC_RAW_AND(dst_reg, src2_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, src2_reg, IMM_L(imm))); + } else if (!IMM_L(imm)) { + EMIT(PPC_RAW_ANDIS(dst_reg, src2_reg, IMM_H(imm))); + } else if (imm == (((1 << fls(imm)) - 1) ^ ((1 << (ffs(i) - 1)) - 1))) { + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 0, + 32 - fls(imm), 32 - ffs(imm))); + } else { + PPC_LI32(_R0, imm); + EMIT(PPC_RAW_AND(dst_reg, src2_reg, _R0)); + } + break; + case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */ + EMIT(PPC_RAW_OR(dst_reg, src2_reg, src_reg)); + EMIT(PPC_RAW_OR(dst_reg_h, src2_reg_h, src_reg_h)); + break; + case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */ + EMIT(PPC_RAW_OR(dst_reg, src2_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, src2_reg, IMM_L(imm))); + src2_reg = dst_reg; + } + if (IMM_H(imm)) + EMIT(PPC_RAW_ORIS(dst_reg, src2_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, src2_reg, src_reg)); + EMIT(PPC_RAW_XOR(dst_reg_h, src2_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, src2_reg, src_reg)); + break; + case BPF_ALU64 | BPF_XOR | BPF_K: /* dst ^= imm */ + if (imm < 0) + EMIT(PPC_RAW_NOR(dst_reg_h, src2_reg_h, src2_reg_h)); + fallthrough; + case BPF_ALU | BPF_XOR | BPF_K: /* (u32) dst ^= (u32) imm */ + if (IMM_L(imm)) { + EMIT(PPC_RAW_XORI(dst_reg, src2_reg, IMM_L(imm))); + src2_reg = dst_reg; + } + if (IMM_H(imm)) + EMIT(PPC_RAW_XORIS(dst_reg, src2_reg, IMM_H(imm))); + break; + case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */ + EMIT(PPC_RAW_SLW(dst_reg, src2_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, src2_reg_h, src_reg)); + EMIT(PPC_RAW_ADDI(tmp_reg, src_reg, 32)); + EMIT(PPC_RAW_SRW(_R0, src2_reg, _R0)); + EMIT(PPC_RAW_SLW(tmp_reg, src2_reg, tmp_reg)); + EMIT(PPC_RAW_OR(dst_reg_h, dst_reg_h, _R0)); + EMIT(PPC_RAW_SLW(dst_reg, src2_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) + EMIT(PPC_RAW_SLWI(dst_reg, src2_reg, imm)); + else + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + break; + case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<= imm */ + if (imm < 0) + return -EINVAL; + if (!imm) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + } else if (imm < 32) { + EMIT(PPC_RAW_RLWINM(dst_reg_h, src2_reg_h, imm, 0, 31 - imm)); + EMIT(PPC_RAW_RLWIMI(dst_reg_h, src2_reg, imm, 32 - imm, 31)); + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, imm, 0, 31 - imm)); + } else if (imm < 64) { + EMIT(PPC_RAW_RLWINM(dst_reg_h, src2_reg, imm, 0, 31 - imm)); + EMIT(PPC_RAW_LI(dst_reg, 0)); + } 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, src2_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, src2_reg, src_reg)); + EMIT(PPC_RAW_ADDI(tmp_reg, src_reg, 32)); + EMIT(PPC_RAW_SLW(_R0, src2_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, src2_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) + EMIT(PPC_RAW_SRWI(dst_reg, src2_reg, imm)); + else + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + break; + case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */ + if (imm < 0) + return -EINVAL; + if (!imm) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src2_reg_h)); + } else if (imm < 32) { + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 32 - imm, imm, 31)); + EMIT(PPC_RAW_RLWIMI(dst_reg, src2_reg_h, 32 - imm, 0, imm - 1)); + EMIT(PPC_RAW_RLWINM(dst_reg_h, src2_reg_h, 32 - imm, imm, 31)); + } else if (imm < 64) { + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg_h, 64 - imm, imm - 32, 31)); + EMIT(PPC_RAW_LI(dst_reg_h, 0)); + } 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, src2_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, src2_reg, src_reg)); + EMIT(PPC_RAW_SLW(_R0, src2_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, src2_reg_h, tmp_reg)); + EMIT(PPC_RAW_SRAW(dst_reg_h, src2_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) + EMIT(PPC_RAW_SRAWI(dst_reg, src2_reg, imm)); + else + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + break; + case BPF_ALU64 | BPF_ARSH | BPF_K: /* (s64) dst >>= imm */ + if (imm < 0) + return -EINVAL; + if (!imm) { + EMIT(PPC_RAW_MR(dst_reg, src2_reg)); + EMIT(PPC_RAW_MR(dst_reg_h, src2_reg_h)); + } else if (imm < 32) { + EMIT(PPC_RAW_RLWINM(dst_reg, src2_reg, 32 - imm, imm, 31)); + EMIT(PPC_RAW_RLWIMI(dst_reg, src2_reg_h, 32 - imm, 0, imm - 1)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, src2_reg_h, imm)); + } else if (imm < 64) { + EMIT(PPC_RAW_SRAWI(dst_reg, src2_reg_h, imm - 32)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, src2_reg_h, 31)); + } else { + EMIT(PPC_RAW_SRAWI(dst_reg, src2_reg_h, 31)); + EMIT(PPC_RAW_SRAWI(dst_reg_h, src2_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, src2_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, src2_reg, 8, 0, 31)); + /* Rotate 24 bits and insert byte 1 */ + EMIT(PPC_RAW_RLWIMI(_R0, src2_reg, 24, 0, 7)); + /* Rotate 24 bits and insert byte 3 */ + EMIT(PPC_RAW_RLWIMI(_R0, src2_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, src2_reg, 8, 0, 31)); + EMIT(PPC_RAW_RLWINM(_R0, src2_reg_h, 8, 0, 31)); + /* Rotate 24 bits and insert byte 1 */ + EMIT(PPC_RAW_RLWIMI(tmp_reg, src2_reg, 24, 0, 7)); + EMIT(PPC_RAW_RLWIMI(_R0, src2_reg_h, 24, 0, 7)); + /* Rotate 24 bits and insert byte 3 */ + EMIT(PPC_RAW_RLWIMI(tmp_reg, src2_reg, 24, 16, 23)); + EMIT(PPC_RAW_RLWIMI(_R0, src2_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, src2_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: + save_reg = _R0; + ret_reg = src_reg; + + bpf_set_seen_register(ctx, tmp_reg); + bpf_set_seen_register(ctx, ax_reg); + + /* Get offset into TMP_REG */ + EMIT(PPC_RAW_LI(tmp_reg, off)); + tmp_idx = ctx->idx * 4; + /* load value from memory into r0 */ + EMIT(PPC_RAW_LWARX(_R0, tmp_reg, dst_reg, 0)); + + /* Save old value in BPF_REG_AX */ + if (imm & BPF_FETCH) + EMIT(PPC_RAW_MR(ax_reg, _R0)); + + switch (imm) { + case BPF_ADD: + case BPF_ADD | BPF_FETCH: + EMIT(PPC_RAW_ADD(_R0, _R0, src_reg)); + break; + case BPF_AND: + case BPF_AND | BPF_FETCH: + EMIT(PPC_RAW_AND(_R0, _R0, src_reg)); + break; + case BPF_OR: + case BPF_OR | BPF_FETCH: + EMIT(PPC_RAW_OR(_R0, _R0, src_reg)); + break; + case BPF_XOR: + case BPF_XOR | BPF_FETCH: + EMIT(PPC_RAW_XOR(_R0, _R0, src_reg)); + break; + case BPF_CMPXCHG: + /* + * Return old value in BPF_REG_0 for BPF_CMPXCHG & + * in src_reg for other cases. + */ + ret_reg = bpf_to_ppc(BPF_REG_0); + + /* Compare with old value in BPF_REG_0 */ + EMIT(PPC_RAW_CMPW(bpf_to_ppc(BPF_REG_0), _R0)); + /* Don't set if different from old value */ + PPC_BCC_SHORT(COND_NE, (ctx->idx + 3) * 4); + fallthrough; + case BPF_XCHG: + save_reg = src_reg; + break; + default: + pr_err_ratelimited("eBPF filter atomic op code %02x (@%d) unsupported\n", + code, i); + return -EOPNOTSUPP; + } + + /* store new value */ + EMIT(PPC_RAW_STWCX(save_reg, tmp_reg, dst_reg)); + /* we're done if this succeeded */ + PPC_BCC_SHORT(COND_NE, tmp_idx); + + /* For the BPF_FETCH variant, get old data into src_reg */ + if (imm & BPF_FETCH) { + EMIT(PPC_RAW_MR(ret_reg, ax_reg)); + if (!fp->aux->verifier_zext) + EMIT(PPC_RAW_LI(ret_reg - 1, 0)); /* higher 32-bit */ + } + 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 */ + if (!image) + 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], extra_pass, + &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; +} diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c new file mode 100644 index 0000000000..0f8048f6da --- /dev/null +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -0,0 +1,1228 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * bpf_jit_comp64.c: eBPF JIT compiler + * + * Copyright 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> + * IBM Corporation + * + * Based on the powerpc classic BPF JIT compiler by Matt Evans + */ +#include <linux/moduleloader.h> +#include <asm/cacheflush.h> +#include <asm/asm-compat.h> +#include <linux/netdevice.h> +#include <linux/filter.h> +#include <linux/if_vlan.h> +#include <asm/kprobes.h> +#include <linux/bpf.h> +#include <asm/security_features.h> + +#include "bpf_jit.h" + +/* + * Stack layout: + * Ensure the top half (upto local_tmp_var) stays consistent + * with our redzone usage. + * + * [ prev sp ] <------------- + * [ nv gpr save area ] 5*8 | + * [ tail_call_cnt ] 8 | + * [ local_tmp_var ] 16 | + * fp (r31) --> [ ebpf stack space ] upto 512 | + * [ frame header ] 32/112 | + * sp (r1) ---> [ stack pointer ] -------------- + */ + +/* for gpr non volatile registers BPG_REG_6 to 10 */ +#define BPF_PPC_STACK_SAVE (5*8) +/* for bpf JIT code internal usage */ +#define BPF_PPC_STACK_LOCALS 24 +/* stack frame excluding BPF stack, ensure this is quadword aligned */ +#define BPF_PPC_STACKFRAME (STACK_FRAME_MIN_SIZE + \ + BPF_PPC_STACK_LOCALS + BPF_PPC_STACK_SAVE) + +/* BPF register usage */ +#define TMP_REG_1 (MAX_BPF_JIT_REG + 0) +#define TMP_REG_2 (MAX_BPF_JIT_REG + 1) + +/* BPF to ppc register mappings */ +void bpf_jit_init_reg_mapping(struct codegen_context *ctx) +{ + /* function return value */ + ctx->b2p[BPF_REG_0] = _R8; + /* function arguments */ + ctx->b2p[BPF_REG_1] = _R3; + ctx->b2p[BPF_REG_2] = _R4; + ctx->b2p[BPF_REG_3] = _R5; + ctx->b2p[BPF_REG_4] = _R6; + ctx->b2p[BPF_REG_5] = _R7; + /* non volatile registers */ + ctx->b2p[BPF_REG_6] = _R27; + ctx->b2p[BPF_REG_7] = _R28; + ctx->b2p[BPF_REG_8] = _R29; + ctx->b2p[BPF_REG_9] = _R30; + /* frame pointer aka BPF_REG_10 */ + ctx->b2p[BPF_REG_FP] = _R31; + /* eBPF jit internal registers */ + ctx->b2p[BPF_REG_AX] = _R12; + ctx->b2p[TMP_REG_1] = _R9; + ctx->b2p[TMP_REG_2] = _R10; +} + +/* PPC NVR range -- update this if we ever use NVRs below r27 */ +#define BPF_PPC_NVR_MIN _R27 + +static inline bool bpf_has_stack_frame(struct codegen_context *ctx) +{ + /* + * We only need a stack frame if: + * - we call other functions (kernel helpers), or + * - the bpf program uses its stack area + * The latter condition is deduced from the usage of BPF_REG_FP + */ + return ctx->seen & SEEN_FUNC || bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_FP)); +} + +/* + * When not setting up our own stackframe, the redzone usage is: + * + * [ prev sp ] <------------- + * [ ... ] | + * sp (r1) ---> [ stack pointer ] -------------- + * [ nv gpr save area ] 5*8 + * [ tail_call_cnt ] 8 + * [ local_tmp_var ] 16 + * [ unused red zone ] 208 bytes protected + */ +static int bpf_jit_stack_local(struct codegen_context *ctx) +{ + if (bpf_has_stack_frame(ctx)) + return STACK_FRAME_MIN_SIZE + ctx->stack_size; + else + return -(BPF_PPC_STACK_SAVE + 24); +} + +static int bpf_jit_stack_tailcallcnt(struct codegen_context *ctx) +{ + return bpf_jit_stack_local(ctx) + 16; +} + +static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg) +{ + if (reg >= BPF_PPC_NVR_MIN && reg < 32) + return (bpf_has_stack_frame(ctx) ? + (BPF_PPC_STACKFRAME + ctx->stack_size) : 0) + - (8 * (32 - reg)); + + pr_err("BPF JIT is asking about unknown registers"); + BUG(); +} + +void bpf_jit_realloc_regs(struct codegen_context *ctx) +{ +} + +void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx) +{ + int i; + +#ifndef CONFIG_PPC_KERNEL_PCREL + if (IS_ENABLED(CONFIG_PPC64_ELF_ABI_V2)) + EMIT(PPC_RAW_LD(_R2, _R13, offsetof(struct paca_struct, kernel_toc))); +#endif + + /* + * Initialize tail_call_cnt if we do tail calls. + * Otherwise, put in NOPs so that it can be skipped when we are + * invoked through a tail call. + */ + if (ctx->seen & SEEN_TAILCALL) { + EMIT(PPC_RAW_LI(bpf_to_ppc(TMP_REG_1), 0)); + /* this goes in the redzone */ + EMIT(PPC_RAW_STD(bpf_to_ppc(TMP_REG_1), _R1, -(BPF_PPC_STACK_SAVE + 8))); + } else { + EMIT(PPC_RAW_NOP()); + EMIT(PPC_RAW_NOP()); + } + + if (bpf_has_stack_frame(ctx)) { + /* + * We need a stack frame, but we don't necessarily need to + * save/restore LR unless we call other functions + */ + if (ctx->seen & SEEN_FUNC) { + EMIT(PPC_RAW_MFLR(_R0)); + EMIT(PPC_RAW_STD(_R0, _R1, PPC_LR_STKOFF)); + } + + EMIT(PPC_RAW_STDU(_R1, _R1, -(BPF_PPC_STACKFRAME + ctx->stack_size))); + } + + /* + * Back up non-volatile regs -- BPF registers 6-10 + * If we haven't created our own stack frame, we save these + * in the protected zone below the previous stack frame + */ + for (i = BPF_REG_6; i <= BPF_REG_10; i++) + if (bpf_is_seen_register(ctx, bpf_to_ppc(i))) + EMIT(PPC_RAW_STD(bpf_to_ppc(i), _R1, bpf_jit_stack_offsetof(ctx, bpf_to_ppc(i)))); + + /* Setup frame pointer to point to the bpf stack area */ + if (bpf_is_seen_register(ctx, bpf_to_ppc(BPF_REG_FP))) + EMIT(PPC_RAW_ADDI(bpf_to_ppc(BPF_REG_FP), _R1, + STACK_FRAME_MIN_SIZE + ctx->stack_size)); +} + +static void bpf_jit_emit_common_epilogue(u32 *image, struct codegen_context *ctx) +{ + int i; + + /* Restore NVRs */ + for (i = BPF_REG_6; i <= BPF_REG_10; i++) + if (bpf_is_seen_register(ctx, bpf_to_ppc(i))) + EMIT(PPC_RAW_LD(bpf_to_ppc(i), _R1, bpf_jit_stack_offsetof(ctx, bpf_to_ppc(i)))); + + /* Tear down our stack frame */ + if (bpf_has_stack_frame(ctx)) { + EMIT(PPC_RAW_ADDI(_R1, _R1, BPF_PPC_STACKFRAME + ctx->stack_size)); + if (ctx->seen & SEEN_FUNC) { + EMIT(PPC_RAW_LD(_R0, _R1, PPC_LR_STKOFF)); + EMIT(PPC_RAW_MTLR(_R0)); + } + } +} + +void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx) +{ + bpf_jit_emit_common_epilogue(image, ctx); + + /* Move result to r3 */ + EMIT(PPC_RAW_MR(_R3, bpf_to_ppc(BPF_REG_0))); + + EMIT(PPC_RAW_BLR()); +} + +static int bpf_jit_emit_func_call_hlp(u32 *image, struct codegen_context *ctx, u64 func) +{ + unsigned long func_addr = func ? ppc_function_entry((void *)func) : 0; + long reladdr; + + if (WARN_ON_ONCE(!core_kernel_text(func_addr))) + return -EINVAL; + + if (IS_ENABLED(CONFIG_PPC_KERNEL_PCREL)) { + reladdr = func_addr - CTX_NIA(ctx); + + if (reladdr >= (long)SZ_8G || reladdr < -(long)SZ_8G) { + pr_err("eBPF: address of %ps out of range of pcrel address.\n", + (void *)func); + return -ERANGE; + } + /* pla r12,addr */ + EMIT(PPC_PREFIX_MLS | __PPC_PRFX_R(1) | IMM_H18(reladdr)); + EMIT(PPC_INST_PADDI | ___PPC_RT(_R12) | IMM_L(reladdr)); + EMIT(PPC_RAW_MTCTR(_R12)); + EMIT(PPC_RAW_BCTR()); + + } else { + reladdr = func_addr - kernel_toc_addr(); + if (reladdr > 0x7FFFFFFF || reladdr < -(0x80000000L)) { + pr_err("eBPF: address of %ps out of range of kernel_toc.\n", (void *)func); + return -ERANGE; + } + + EMIT(PPC_RAW_ADDIS(_R12, _R2, PPC_HA(reladdr))); + EMIT(PPC_RAW_ADDI(_R12, _R12, PPC_LO(reladdr))); + EMIT(PPC_RAW_MTCTR(_R12)); + EMIT(PPC_RAW_BCTRL()); + } + + return 0; +} + +int bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 func) +{ + unsigned int i, ctx_idx = ctx->idx; + + if (WARN_ON_ONCE(func && is_module_text_address(func))) + return -EINVAL; + + /* skip past descriptor if elf v1 */ + func += FUNCTION_DESCR_SIZE; + + /* Load function address into r12 */ + PPC_LI64(_R12, func); + + /* For bpf-to-bpf function calls, the callee's address is unknown + * until the last extra pass. As seen above, we use PPC_LI64() to + * load the callee's address, but this may optimize the number of + * instructions required based on the nature of the address. + * + * Since we don't want the number of instructions emitted to increase, + * we pad the optimized PPC_LI64() call with NOPs to guarantee that + * we always have a five-instruction sequence, which is the maximum + * that PPC_LI64() can emit. + */ + if (!image) + for (i = ctx->idx - ctx_idx; i < 5; i++) + EMIT(PPC_RAW_NOP()); + + EMIT(PPC_RAW_MTCTR(_R12)); + EMIT(PPC_RAW_BCTRL()); + + return 0; +} + +static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 out) +{ + /* + * By now, the eBPF program has already setup parameters in r3, r4 and r5 + * r3/BPF_REG_1 - pointer to ctx -- passed as is to the next bpf program + * r4/BPF_REG_2 - pointer to bpf_array + * r5/BPF_REG_3 - index in bpf_array + */ + int b2p_bpf_array = bpf_to_ppc(BPF_REG_2); + int b2p_index = bpf_to_ppc(BPF_REG_3); + int bpf_tailcall_prologue_size = 8; + + if (IS_ENABLED(CONFIG_PPC64_ELF_ABI_V2)) + bpf_tailcall_prologue_size += 4; /* skip past the toc load */ + + /* + * if (index >= array->map.max_entries) + * goto out; + */ + EMIT(PPC_RAW_LWZ(bpf_to_ppc(TMP_REG_1), b2p_bpf_array, offsetof(struct bpf_array, map.max_entries))); + EMIT(PPC_RAW_RLWINM(b2p_index, b2p_index, 0, 0, 31)); + EMIT(PPC_RAW_CMPLW(b2p_index, bpf_to_ppc(TMP_REG_1))); + PPC_BCC_SHORT(COND_GE, out); + + /* + * if (tail_call_cnt >= MAX_TAIL_CALL_CNT) + * goto out; + */ + EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_1), _R1, bpf_jit_stack_tailcallcnt(ctx))); + EMIT(PPC_RAW_CMPLWI(bpf_to_ppc(TMP_REG_1), MAX_TAIL_CALL_CNT)); + PPC_BCC_SHORT(COND_GE, out); + + /* + * tail_call_cnt++; + */ + EMIT(PPC_RAW_ADDI(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), 1)); + EMIT(PPC_RAW_STD(bpf_to_ppc(TMP_REG_1), _R1, bpf_jit_stack_tailcallcnt(ctx))); + + /* prog = array->ptrs[index]; */ + EMIT(PPC_RAW_MULI(bpf_to_ppc(TMP_REG_1), b2p_index, 8)); + EMIT(PPC_RAW_ADD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), b2p_bpf_array)); + EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), offsetof(struct bpf_array, ptrs))); + + /* + * if (prog == NULL) + * goto out; + */ + EMIT(PPC_RAW_CMPLDI(bpf_to_ppc(TMP_REG_1), 0)); + PPC_BCC_SHORT(COND_EQ, out); + + /* goto *(prog->bpf_func + prologue_size); */ + EMIT(PPC_RAW_LD(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), offsetof(struct bpf_prog, bpf_func))); + EMIT(PPC_RAW_ADDI(bpf_to_ppc(TMP_REG_1), bpf_to_ppc(TMP_REG_1), + FUNCTION_DESCR_SIZE + bpf_tailcall_prologue_size)); + EMIT(PPC_RAW_MTCTR(bpf_to_ppc(TMP_REG_1))); + + /* tear down stack, restore NVRs, ... */ + bpf_jit_emit_common_epilogue(image, ctx); + + EMIT(PPC_RAW_BCTR()); + + /* out: */ + return 0; +} + +/* + * We spill into the redzone always, even if the bpf program has its own stackframe. + * Offsets hardcoded based on BPF_PPC_STACK_SAVE -- see bpf_jit_stack_local() + */ +void bpf_stf_barrier(void); + +asm ( +" .global bpf_stf_barrier ;" +" bpf_stf_barrier: ;" +" std 21,-64(1) ;" +" std 22,-56(1) ;" +" sync ;" +" ld 21,-64(1) ;" +" ld 22,-56(1) ;" +" ori 31,31,0 ;" +" .rept 14 ;" +" b 1f ;" +" 1: ;" +" .endr ;" +" blr ;" +); + +/* Assemble the body code between the prologue & epilogue */ +int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx, + u32 *addrs, int pass, bool extra_pass) +{ + enum stf_barrier_type stf_barrier = stf_barrier_type_get(); + const struct bpf_insn *insn = fp->insnsi; + int flen = fp->len; + int i, ret; + + /* Start of epilogue code - will only be valid 2nd pass onwards */ + u32 exit_addr = addrs[flen]; + + for (i = 0; i < flen; i++) { + u32 code = insn[i].code; + u32 dst_reg = bpf_to_ppc(insn[i].dst_reg); + u32 src_reg = bpf_to_ppc(insn[i].src_reg); + u32 size = BPF_SIZE(code); + u32 tmp1_reg = bpf_to_ppc(TMP_REG_1); + u32 tmp2_reg = bpf_to_ppc(TMP_REG_2); + u32 save_reg, ret_reg; + s16 off = insn[i].off; + s32 imm = insn[i].imm; + bool func_addr_fixed; + u64 func_addr; + u64 imm64; + u32 true_cond; + u32 tmp_idx; + int j; + + /* + * addrs[] maps a BPF bytecode address into a real offset from + * the start of the body code. + */ + addrs[i] = ctx->idx * 4; + + /* + * As an optimization, we note down which non-volatile registers + * are used so that we can only save/restore those in our + * prologue and epilogue. We do this here regardless of whether + * the actual BPF instruction uses src/dst registers or not + * (for instance, BPF_CALL does not use them). The expectation + * is that those instructions will have src_reg/dst_reg set to + * 0. Even otherwise, we just lose some prologue/epilogue + * optimization but everything else should work without + * any issues. + */ + if (dst_reg >= BPF_PPC_NVR_MIN && dst_reg < 32) + bpf_set_seen_register(ctx, dst_reg); + if (src_reg >= BPF_PPC_NVR_MIN && src_reg < 32) + bpf_set_seen_register(ctx, src_reg); + + switch (code) { + /* + * Arithmetic operations: ADD/SUB/MUL/DIV/MOD/NEG + */ + case BPF_ALU | BPF_ADD | BPF_X: /* (u32) dst += (u32) src */ + case BPF_ALU64 | BPF_ADD | BPF_X: /* dst += src */ + EMIT(PPC_RAW_ADD(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_SUB | BPF_X: /* (u32) dst -= (u32) src */ + case BPF_ALU64 | BPF_SUB | BPF_X: /* dst -= src */ + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_ADD | BPF_K: /* (u32) dst += (u32) imm */ + case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */ + if (!imm) { + goto bpf_alu32_trunc; + } else if (imm >= -32768 && imm < 32768) { + EMIT(PPC_RAW_ADDI(dst_reg, dst_reg, IMM_L(imm))); + } else { + PPC_LI32(tmp1_reg, imm); + EMIT(PPC_RAW_ADD(dst_reg, dst_reg, tmp1_reg)); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */ + case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */ + if (!imm) { + goto bpf_alu32_trunc; + } else if (imm > -32768 && imm <= 32768) { + EMIT(PPC_RAW_ADDI(dst_reg, dst_reg, IMM_L(-imm))); + } else { + PPC_LI32(tmp1_reg, imm); + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg)); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */ + case BPF_ALU64 | BPF_MUL | BPF_X: /* dst *= src */ + if (BPF_CLASS(code) == BPF_ALU) + EMIT(PPC_RAW_MULW(dst_reg, dst_reg, src_reg)); + else + EMIT(PPC_RAW_MULD(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_MUL | BPF_K: /* (u32) dst *= (u32) imm */ + case BPF_ALU64 | BPF_MUL | BPF_K: /* dst *= imm */ + if (imm >= -32768 && imm < 32768) + EMIT(PPC_RAW_MULI(dst_reg, dst_reg, IMM_L(imm))); + else { + PPC_LI32(tmp1_reg, imm); + if (BPF_CLASS(code) == BPF_ALU) + EMIT(PPC_RAW_MULW(dst_reg, dst_reg, tmp1_reg)); + else + EMIT(PPC_RAW_MULD(dst_reg, dst_reg, tmp1_reg)); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */ + case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */ + if (BPF_OP(code) == BPF_MOD) { + EMIT(PPC_RAW_DIVWU(tmp1_reg, dst_reg, src_reg)); + EMIT(PPC_RAW_MULW(tmp1_reg, src_reg, tmp1_reg)); + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg)); + } else + EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */ + case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */ + if (BPF_OP(code) == BPF_MOD) { + EMIT(PPC_RAW_DIVDU(tmp1_reg, dst_reg, src_reg)); + EMIT(PPC_RAW_MULD(tmp1_reg, src_reg, tmp1_reg)); + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg)); + } else + EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg, src_reg)); + break; + case BPF_ALU | BPF_MOD | BPF_K: /* (u32) dst %= (u32) imm */ + case BPF_ALU | BPF_DIV | BPF_K: /* (u32) dst /= (u32) imm */ + case BPF_ALU64 | BPF_MOD | BPF_K: /* dst %= imm */ + case BPF_ALU64 | BPF_DIV | BPF_K: /* dst /= imm */ + if (imm == 0) + return -EINVAL; + if (imm == 1) { + if (BPF_OP(code) == BPF_DIV) { + goto bpf_alu32_trunc; + } else { + EMIT(PPC_RAW_LI(dst_reg, 0)); + break; + } + } + + PPC_LI32(tmp1_reg, imm); + switch (BPF_CLASS(code)) { + case BPF_ALU: + if (BPF_OP(code) == BPF_MOD) { + EMIT(PPC_RAW_DIVWU(tmp2_reg, dst_reg, tmp1_reg)); + EMIT(PPC_RAW_MULW(tmp1_reg, tmp1_reg, tmp2_reg)); + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg)); + } else + EMIT(PPC_RAW_DIVWU(dst_reg, dst_reg, tmp1_reg)); + break; + case BPF_ALU64: + if (BPF_OP(code) == BPF_MOD) { + EMIT(PPC_RAW_DIVDU(tmp2_reg, dst_reg, tmp1_reg)); + EMIT(PPC_RAW_MULD(tmp1_reg, tmp1_reg, tmp2_reg)); + EMIT(PPC_RAW_SUB(dst_reg, dst_reg, tmp1_reg)); + } else + EMIT(PPC_RAW_DIVDU(dst_reg, dst_reg, tmp1_reg)); + break; + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_NEG: /* (u32) dst = -dst */ + case BPF_ALU64 | BPF_NEG: /* dst = -dst */ + EMIT(PPC_RAW_NEG(dst_reg, dst_reg)); + goto bpf_alu32_trunc; + + /* + * Logical operations: AND/OR/XOR/[A]LSH/[A]RSH + */ + case BPF_ALU | BPF_AND | BPF_X: /* (u32) dst = dst & src */ + case BPF_ALU64 | BPF_AND | BPF_X: /* dst = dst & src */ + EMIT(PPC_RAW_AND(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_AND | BPF_K: /* (u32) dst = dst & imm */ + case BPF_ALU64 | BPF_AND | BPF_K: /* dst = dst & imm */ + if (!IMM_H(imm)) + EMIT(PPC_RAW_ANDI(dst_reg, dst_reg, IMM_L(imm))); + else { + /* Sign-extended */ + PPC_LI32(tmp1_reg, imm); + EMIT(PPC_RAW_AND(dst_reg, dst_reg, tmp1_reg)); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */ + case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */ + EMIT(PPC_RAW_OR(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_OR | BPF_K:/* dst = (u32) dst | (u32) imm */ + case BPF_ALU64 | BPF_OR | BPF_K:/* dst = dst | imm */ + if (imm < 0 && BPF_CLASS(code) == BPF_ALU64) { + /* Sign-extended */ + PPC_LI32(tmp1_reg, imm); + EMIT(PPC_RAW_OR(dst_reg, dst_reg, tmp1_reg)); + } else { + 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))); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_XOR | BPF_X: /* (u32) dst ^= src */ + case BPF_ALU64 | BPF_XOR | BPF_X: /* dst ^= src */ + EMIT(PPC_RAW_XOR(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_XOR | BPF_K: /* (u32) dst ^= (u32) imm */ + case BPF_ALU64 | BPF_XOR | BPF_K: /* dst ^= imm */ + if (imm < 0 && BPF_CLASS(code) == BPF_ALU64) { + /* Sign-extended */ + PPC_LI32(tmp1_reg, imm); + EMIT(PPC_RAW_XOR(dst_reg, dst_reg, tmp1_reg)); + } else { + 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))); + } + goto bpf_alu32_trunc; + case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */ + /* slw clears top 32 bits */ + EMIT(PPC_RAW_SLW(dst_reg, dst_reg, src_reg)); + /* skip zero extension move, but set address map. */ + if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + case BPF_ALU64 | BPF_LSH | BPF_X: /* dst <<= src; */ + EMIT(PPC_RAW_SLD(dst_reg, dst_reg, src_reg)); + break; + case BPF_ALU | BPF_LSH | BPF_K: /* (u32) dst <<== (u32) imm */ + /* with imm 0, we still need to clear top 32 bits */ + EMIT(PPC_RAW_SLWI(dst_reg, dst_reg, imm)); + if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<== imm */ + if (imm != 0) + EMIT(PPC_RAW_SLDI(dst_reg, dst_reg, imm)); + break; + case BPF_ALU | BPF_RSH | BPF_X: /* (u32) dst >>= (u32) src */ + EMIT(PPC_RAW_SRW(dst_reg, dst_reg, src_reg)); + if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + case BPF_ALU64 | BPF_RSH | BPF_X: /* dst >>= src */ + EMIT(PPC_RAW_SRD(dst_reg, dst_reg, src_reg)); + break; + case BPF_ALU | BPF_RSH | BPF_K: /* (u32) dst >>= (u32) imm */ + EMIT(PPC_RAW_SRWI(dst_reg, dst_reg, imm)); + if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */ + if (imm != 0) + EMIT(PPC_RAW_SRDI(dst_reg, dst_reg, imm)); + break; + case BPF_ALU | BPF_ARSH | BPF_X: /* (s32) dst >>= src */ + EMIT(PPC_RAW_SRAW(dst_reg, dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU64 | BPF_ARSH | BPF_X: /* (s64) dst >>= src */ + EMIT(PPC_RAW_SRAD(dst_reg, dst_reg, src_reg)); + break; + case BPF_ALU | BPF_ARSH | BPF_K: /* (s32) dst >>= imm */ + EMIT(PPC_RAW_SRAWI(dst_reg, dst_reg, imm)); + goto bpf_alu32_trunc; + case BPF_ALU64 | BPF_ARSH | BPF_K: /* (s64) dst >>= imm */ + if (imm != 0) + EMIT(PPC_RAW_SRADI(dst_reg, dst_reg, imm)); + break; + + /* + * MOV + */ + case BPF_ALU | BPF_MOV | BPF_X: /* (u32) dst = src */ + case BPF_ALU64 | BPF_MOV | BPF_X: /* dst = src */ + if (imm == 1) { + /* special mov32 for zext */ + EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 0, 31)); + break; + } + EMIT(PPC_RAW_MR(dst_reg, src_reg)); + goto bpf_alu32_trunc; + case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */ + case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = (s64) imm */ + PPC_LI32(dst_reg, imm); + if (imm < 0) + goto bpf_alu32_trunc; + else if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + +bpf_alu32_trunc: + /* Truncate to 32-bits */ + if (BPF_CLASS(code) == BPF_ALU && !fp->aux->verifier_zext) + EMIT(PPC_RAW_RLWINM(dst_reg, dst_reg, 0, 0, 31)); + break; + + /* + * BPF_FROM_BE/LE + */ + case BPF_ALU | BPF_END | BPF_FROM_LE: + case BPF_ALU | BPF_END | BPF_FROM_BE: +#ifdef __BIG_ENDIAN__ + if (BPF_SRC(code) == BPF_FROM_BE) + goto emit_clear; +#else /* !__BIG_ENDIAN__ */ + if (BPF_SRC(code) == BPF_FROM_LE) + goto emit_clear; +#endif + switch (imm) { + case 16: + /* Rotate 8 bits left & mask with 0x0000ff00 */ + EMIT(PPC_RAW_RLWINM(tmp1_reg, dst_reg, 8, 16, 23)); + /* Rotate 8 bits right & insert LSB to reg */ + EMIT(PPC_RAW_RLWIMI(tmp1_reg, dst_reg, 24, 24, 31)); + /* Move result back to dst_reg */ + EMIT(PPC_RAW_MR(dst_reg, tmp1_reg)); + 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(tmp1_reg, dst_reg, 8, 0, 31)); + /* Rotate 24 bits and insert byte 1 */ + EMIT(PPC_RAW_RLWIMI(tmp1_reg, dst_reg, 24, 0, 7)); + /* Rotate 24 bits and insert byte 3 */ + EMIT(PPC_RAW_RLWIMI(tmp1_reg, dst_reg, 24, 16, 23)); + EMIT(PPC_RAW_MR(dst_reg, tmp1_reg)); + break; + case 64: + /* Store the value to stack and then use byte-reverse loads */ + EMIT(PPC_RAW_STD(dst_reg, _R1, bpf_jit_stack_local(ctx))); + EMIT(PPC_RAW_ADDI(tmp1_reg, _R1, bpf_jit_stack_local(ctx))); + if (cpu_has_feature(CPU_FTR_ARCH_206)) { + EMIT(PPC_RAW_LDBRX(dst_reg, 0, tmp1_reg)); + } else { + EMIT(PPC_RAW_LWBRX(dst_reg, 0, tmp1_reg)); + if (IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN)) + EMIT(PPC_RAW_SLDI(dst_reg, dst_reg, 32)); + EMIT(PPC_RAW_LI(tmp2_reg, 4)); + EMIT(PPC_RAW_LWBRX(tmp2_reg, tmp2_reg, tmp1_reg)); + if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN)) + EMIT(PPC_RAW_SLDI(tmp2_reg, tmp2_reg, 32)); + EMIT(PPC_RAW_OR(dst_reg, dst_reg, tmp2_reg)); + } + break; + } + break; + +emit_clear: + switch (imm) { + case 16: + /* zero-extend 16 bits into 64 bits */ + EMIT(PPC_RAW_RLDICL(dst_reg, dst_reg, 0, 48)); + if (insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + break; + case 32: + if (!fp->aux->verifier_zext) + /* zero-extend 32 bits into 64 bits */ + EMIT(PPC_RAW_RLDICL(dst_reg, dst_reg, 0, 32)); + break; + case 64: + /* nop */ + break; + } + break; + + /* + * BPF_ST NOSPEC (speculation barrier) + */ + case BPF_ST | BPF_NOSPEC: + if (!security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) || + !security_ftr_enabled(SEC_FTR_STF_BARRIER)) + break; + + switch (stf_barrier) { + case STF_BARRIER_EIEIO: + EMIT(PPC_RAW_EIEIO() | 0x02000000); + break; + case STF_BARRIER_SYNC_ORI: + EMIT(PPC_RAW_SYNC()); + EMIT(PPC_RAW_LD(tmp1_reg, _R13, 0)); + EMIT(PPC_RAW_ORI(_R31, _R31, 0)); + break; + case STF_BARRIER_FALLBACK: + ctx->seen |= SEEN_FUNC; + PPC_LI64(_R12, dereference_kernel_function_descriptor(bpf_stf_barrier)); + EMIT(PPC_RAW_MTCTR(_R12)); + EMIT(PPC_RAW_BCTRL()); + break; + case STF_BARRIER_NONE: + break; + } + break; + + /* + * BPF_ST(X) + */ + case BPF_STX | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = src */ + case BPF_ST | BPF_MEM | BPF_B: /* *(u8 *)(dst + off) = imm */ + if (BPF_CLASS(code) == BPF_ST) { + EMIT(PPC_RAW_LI(tmp1_reg, imm)); + src_reg = tmp1_reg; + } + EMIT(PPC_RAW_STB(src_reg, dst_reg, off)); + break; + case BPF_STX | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = src */ + case BPF_ST | BPF_MEM | BPF_H: /* (u16 *)(dst + off) = imm */ + if (BPF_CLASS(code) == BPF_ST) { + EMIT(PPC_RAW_LI(tmp1_reg, imm)); + src_reg = tmp1_reg; + } + EMIT(PPC_RAW_STH(src_reg, dst_reg, off)); + break; + case BPF_STX | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = src */ + case BPF_ST | BPF_MEM | BPF_W: /* *(u32 *)(dst + off) = imm */ + if (BPF_CLASS(code) == BPF_ST) { + PPC_LI32(tmp1_reg, imm); + src_reg = tmp1_reg; + } + EMIT(PPC_RAW_STW(src_reg, dst_reg, off)); + break; + case BPF_STX | BPF_MEM | BPF_DW: /* (u64 *)(dst + off) = src */ + case BPF_ST | BPF_MEM | BPF_DW: /* *(u64 *)(dst + off) = imm */ + if (BPF_CLASS(code) == BPF_ST) { + PPC_LI32(tmp1_reg, imm); + src_reg = tmp1_reg; + } + if (off % 4) { + EMIT(PPC_RAW_LI(tmp2_reg, off)); + EMIT(PPC_RAW_STDX(src_reg, dst_reg, tmp2_reg)); + } else { + EMIT(PPC_RAW_STD(src_reg, dst_reg, off)); + } + break; + + /* + * BPF_STX ATOMIC (atomic ops) + */ + case BPF_STX | BPF_ATOMIC | BPF_W: + case BPF_STX | BPF_ATOMIC | BPF_DW: + save_reg = tmp2_reg; + ret_reg = src_reg; + + /* Get offset into TMP_REG_1 */ + EMIT(PPC_RAW_LI(tmp1_reg, off)); + tmp_idx = ctx->idx * 4; + /* load value from memory into TMP_REG_2 */ + if (size == BPF_DW) + EMIT(PPC_RAW_LDARX(tmp2_reg, tmp1_reg, dst_reg, 0)); + else + EMIT(PPC_RAW_LWARX(tmp2_reg, tmp1_reg, dst_reg, 0)); + + /* Save old value in _R0 */ + if (imm & BPF_FETCH) + EMIT(PPC_RAW_MR(_R0, tmp2_reg)); + + switch (imm) { + case BPF_ADD: + case BPF_ADD | BPF_FETCH: + EMIT(PPC_RAW_ADD(tmp2_reg, tmp2_reg, src_reg)); + break; + case BPF_AND: + case BPF_AND | BPF_FETCH: + EMIT(PPC_RAW_AND(tmp2_reg, tmp2_reg, src_reg)); + break; + case BPF_OR: + case BPF_OR | BPF_FETCH: + EMIT(PPC_RAW_OR(tmp2_reg, tmp2_reg, src_reg)); + break; + case BPF_XOR: + case BPF_XOR | BPF_FETCH: + EMIT(PPC_RAW_XOR(tmp2_reg, tmp2_reg, src_reg)); + break; + case BPF_CMPXCHG: + /* + * Return old value in BPF_REG_0 for BPF_CMPXCHG & + * in src_reg for other cases. + */ + ret_reg = bpf_to_ppc(BPF_REG_0); + + /* Compare with old value in BPF_R0 */ + if (size == BPF_DW) + EMIT(PPC_RAW_CMPD(bpf_to_ppc(BPF_REG_0), tmp2_reg)); + else + EMIT(PPC_RAW_CMPW(bpf_to_ppc(BPF_REG_0), tmp2_reg)); + /* Don't set if different from old value */ + PPC_BCC_SHORT(COND_NE, (ctx->idx + 3) * 4); + fallthrough; + case BPF_XCHG: + save_reg = src_reg; + break; + default: + pr_err_ratelimited( + "eBPF filter atomic op code %02x (@%d) unsupported\n", + code, i); + return -EOPNOTSUPP; + } + + /* store new value */ + if (size == BPF_DW) + EMIT(PPC_RAW_STDCX(save_reg, tmp1_reg, dst_reg)); + else + EMIT(PPC_RAW_STWCX(save_reg, tmp1_reg, dst_reg)); + /* we're done if this succeeded */ + PPC_BCC_SHORT(COND_NE, tmp_idx); + + if (imm & BPF_FETCH) { + EMIT(PPC_RAW_MR(ret_reg, _R0)); + /* + * Skip unnecessary zero-extension for 32-bit cmpxchg. + * For context, see commit 39491867ace5. + */ + if (size != BPF_DW && imm == BPF_CMPXCHG && + insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + } + break; + + /* + * BPF_LDX + */ + /* dst = *(u8 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEM | BPF_B: + case BPF_LDX | BPF_PROBE_MEM | BPF_B: + /* dst = *(u16 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEM | BPF_H: + case BPF_LDX | BPF_PROBE_MEM | BPF_H: + /* dst = *(u32 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEM | BPF_W: + case BPF_LDX | BPF_PROBE_MEM | BPF_W: + /* dst = *(u64 *)(ul) (src + off) */ + case BPF_LDX | BPF_MEM | BPF_DW: + 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) { + EMIT(PPC_RAW_ADDI(tmp1_reg, src_reg, off)); + if (IS_ENABLED(CONFIG_PPC_BOOK3E_64)) + PPC_LI64(tmp2_reg, 0x8000000000000000ul); + else /* BOOK3S_64 */ + PPC_LI64(tmp2_reg, PAGE_OFFSET); + EMIT(PPC_RAW_CMPLD(tmp1_reg, tmp2_reg)); + PPC_BCC_SHORT(COND_GT, (ctx->idx + 3) * 4); + EMIT(PPC_RAW_LI(dst_reg, 0)); + /* + * Check if 'off' is word aligned for BPF_DW, because + * we might generate two instructions. + */ + if (BPF_SIZE(code) == BPF_DW && (off & 3)) + 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: + if (off % 4) { + EMIT(PPC_RAW_LI(tmp1_reg, off)); + EMIT(PPC_RAW_LDX(dst_reg, src_reg, tmp1_reg)); + } else { + EMIT(PPC_RAW_LD(dst_reg, src_reg, off)); + } + break; + } + + if (size != BPF_DW && insn_is_zext(&insn[i + 1])) + addrs[++i] = ctx->idx * 4; + + if (BPF_MODE(code) == BPF_PROBE_MEM) { + ret = bpf_add_extable_entry(fp, image, pass, ctx, ctx->idx - 1, + 4, 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 */ + imm64 = ((u64)(u32) insn[i].imm) | + (((u64)(u32) insn[i+1].imm) << 32); + tmp_idx = ctx->idx; + PPC_LI64(dst_reg, imm64); + /* padding to allow full 5 instructions for later patching */ + if (!image) + for (j = ctx->idx - tmp_idx; j < 5; 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, tmp1_reg, 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], extra_pass, + &func_addr, &func_addr_fixed); + if (ret < 0) + return ret; + + if (func_addr_fixed) + ret = bpf_jit_emit_func_call_hlp(image, ctx, func_addr); + else + ret = bpf_jit_emit_func_call_rel(image, ctx, func_addr); + + if (ret) + return ret; + + /* move return value from r3 to BPF_REG_0 */ + EMIT(PPC_RAW_MR(bpf_to_ppc(BPF_REG_0), _R3)); + 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; + /* Fall through */ + +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: + 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 */ + if (BPF_CLASS(code) == BPF_JMP32) + EMIT(PPC_RAW_CMPLW(dst_reg, src_reg)); + else + EMIT(PPC_RAW_CMPLD(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: + 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 */ + if (BPF_CLASS(code) == BPF_JMP32) + EMIT(PPC_RAW_CMPW(dst_reg, src_reg)); + else + EMIT(PPC_RAW_CMPD(dst_reg, src_reg)); + break; + case BPF_JMP | BPF_JSET | BPF_X: + case BPF_JMP32 | BPF_JSET | BPF_X: + if (BPF_CLASS(code) == BPF_JMP) { + EMIT(PPC_RAW_AND_DOT(tmp1_reg, dst_reg, src_reg)); + } else { + EMIT(PPC_RAW_AND(tmp1_reg, dst_reg, src_reg)); + EMIT(PPC_RAW_RLWINM_DOT(tmp1_reg, tmp1_reg, 0, 0, 31)); + } + 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: + 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: + { + bool is_jmp32 = BPF_CLASS(code) == BPF_JMP32; + + /* + * Need sign-extended load, so only positive + * values can be used as imm in cmpldi + */ + if (imm >= 0 && imm < 32768) { + if (is_jmp32) + EMIT(PPC_RAW_CMPLWI(dst_reg, imm)); + else + EMIT(PPC_RAW_CMPLDI(dst_reg, imm)); + } else { + /* sign-extending load */ + PPC_LI32(tmp1_reg, imm); + /* ... but unsigned comparison */ + if (is_jmp32) + EMIT(PPC_RAW_CMPLW(dst_reg, tmp1_reg)); + else + EMIT(PPC_RAW_CMPLD(dst_reg, tmp1_reg)); + } + 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: + 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: + { + bool is_jmp32 = BPF_CLASS(code) == BPF_JMP32; + + /* + * signed comparison, so any 16-bit value + * can be used in cmpdi + */ + if (imm >= -32768 && imm < 32768) { + if (is_jmp32) + EMIT(PPC_RAW_CMPWI(dst_reg, imm)); + else + EMIT(PPC_RAW_CMPDI(dst_reg, imm)); + } else { + PPC_LI32(tmp1_reg, imm); + if (is_jmp32) + EMIT(PPC_RAW_CMPW(dst_reg, tmp1_reg)); + else + EMIT(PPC_RAW_CMPD(dst_reg, tmp1_reg)); + } + break; + } + case BPF_JMP | BPF_JSET | BPF_K: + 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(tmp1_reg, dst_reg, imm)); + else { + PPC_LI32(tmp1_reg, imm); + if (BPF_CLASS(code) == BPF_JMP) { + EMIT(PPC_RAW_AND_DOT(tmp1_reg, dst_reg, + tmp1_reg)); + } else { + EMIT(PPC_RAW_AND(tmp1_reg, dst_reg, tmp1_reg)); + EMIT(PPC_RAW_RLWINM_DOT(tmp1_reg, tmp1_reg, + 0, 0, 31)); + } + } + 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 -ENOTSUPP; + } + } + + /* Set end-of-body-code address for exit. */ + addrs[i] = ctx->idx * 4; + + return 0; +} |