diff options
103 files changed, 2992 insertions, 621 deletions
diff --git a/MAINTAINERS b/MAINTAINERS index b3a8ca6aa3ed..7cb7f4c3ad3f 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1161,7 +1161,7 @@ M: Brendan Higgins <brendanhiggins@google.com> R: Benjamin Herrenschmidt <benh@kernel.crashing.org> R: Joel Stanley <joel@jms.id.au> L: linux-i2c@vger.kernel.org -L: openbmc@lists.ozlabs.org +L: openbmc@lists.ozlabs.org (moderated for non-subscribers) S: Maintained F: drivers/irqchip/irq-aspeed-i2c-ic.c F: drivers/i2c/busses/i2c-aspeed.c @@ -5835,7 +5835,7 @@ F: drivers/staging/greybus/spi.c F: drivers/staging/greybus/spilib.c F: drivers/staging/greybus/spilib.h -GREYBUS LOOBACK/TIME PROTOCOLS DRIVERS +GREYBUS LOOPBACK/TIME PROTOCOLS DRIVERS M: Bryan O'Donoghue <pure.logic@nexus-software.ie> S: Maintained F: drivers/staging/greybus/loopback.c diff --git a/arch/mips/net/ebpf_jit.c b/arch/mips/net/ebpf_jit.c new file mode 100644 index 000000000000..3f87b96da5c4 --- /dev/null +++ b/arch/mips/net/ebpf_jit.c @@ -0,0 +1,1950 @@ +/* + * Just-In-Time compiler for eBPF filters on MIPS + * + * Copyright (c) 2017 Cavium, Inc. + * + * Based on code from: + * + * Copyright (c) 2014 Imagination Technologies Ltd. + * Author: Markos Chandras <markos.chandras@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; version 2 of the License. + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/filter.h> +#include <linux/bpf.h> +#include <linux/slab.h> +#include <asm/bitops.h> +#include <asm/byteorder.h> +#include <asm/cacheflush.h> +#include <asm/cpu-features.h> +#include <asm/uasm.h> + +/* Registers used by JIT */ +#define MIPS_R_ZERO 0 +#define MIPS_R_AT 1 +#define MIPS_R_V0 2 /* BPF_R0 */ +#define MIPS_R_V1 3 +#define MIPS_R_A0 4 /* BPF_R1 */ +#define MIPS_R_A1 5 /* BPF_R2 */ +#define MIPS_R_A2 6 /* BPF_R3 */ +#define MIPS_R_A3 7 /* BPF_R4 */ +#define MIPS_R_A4 8 /* BPF_R5 */ +#define MIPS_R_T4 12 /* BPF_AX */ +#define MIPS_R_T5 13 +#define MIPS_R_T6 14 +#define MIPS_R_T7 15 +#define MIPS_R_S0 16 /* BPF_R6 */ +#define MIPS_R_S1 17 /* BPF_R7 */ +#define MIPS_R_S2 18 /* BPF_R8 */ +#define MIPS_R_S3 19 /* BPF_R9 */ +#define MIPS_R_S4 20 /* BPF_TCC */ +#define MIPS_R_S5 21 +#define MIPS_R_S6 22 +#define MIPS_R_S7 23 +#define MIPS_R_T8 24 +#define MIPS_R_T9 25 +#define MIPS_R_SP 29 +#define MIPS_R_RA 31 + +/* eBPF flags */ +#define EBPF_SAVE_S0 BIT(0) +#define EBPF_SAVE_S1 BIT(1) +#define EBPF_SAVE_S2 BIT(2) +#define EBPF_SAVE_S3 BIT(3) +#define EBPF_SAVE_S4 BIT(4) +#define EBPF_SAVE_RA BIT(5) +#define EBPF_SEEN_FP BIT(6) +#define EBPF_SEEN_TC BIT(7) +#define EBPF_TCC_IN_V1 BIT(8) + +/* + * For the mips64 ISA, we need to track the value range or type for + * each JIT register. The BPF machine requires zero extended 32-bit + * values, but the mips64 ISA requires sign extended 32-bit values. + * At each point in the BPF program we track the state of every + * register so that we can zero extend or sign extend as the BPF + * semantics require. + */ +enum reg_val_type { + /* uninitialized */ + REG_UNKNOWN, + /* not known to be 32-bit compatible. */ + REG_64BIT, + /* 32-bit compatible, no truncation needed for 64-bit ops. */ + REG_64BIT_32BIT, + /* 32-bit compatible, need truncation for 64-bit ops. */ + REG_32BIT, + /* 32-bit zero extended. */ + REG_32BIT_ZERO_EX, + /* 32-bit no sign/zero extension needed. */ + REG_32BIT_POS +}; + +/* + * high bit of offsets indicates if long branch conversion done at + * this insn. + */ +#define OFFSETS_B_CONV BIT(31) + +/** + * struct jit_ctx - JIT context + * @skf: The sk_filter + * @stack_size: eBPF stack size + * @tmp_offset: eBPF $sp offset to 8-byte temporary memory + * @idx: Instruction index + * @flags: JIT flags + * @offsets: Instruction offsets + * @target: Memory location for the compiled filter + * @reg_val_types Packed enum reg_val_type for each register. + */ +struct jit_ctx { + const struct bpf_prog *skf; + int stack_size; + int tmp_offset; + u32 idx; + u32 flags; + u32 *offsets; + u32 *target; + u64 *reg_val_types; + unsigned int long_b_conversion:1; + unsigned int gen_b_offsets:1; +}; + +static void set_reg_val_type(u64 *rvt, int reg, enum reg_val_type type) +{ + *rvt &= ~(7ull << (reg * 3)); + *rvt |= ((u64)type << (reg * 3)); +} + +static enum reg_val_type get_reg_val_type(const struct jit_ctx *ctx, + int index, int reg) +{ + return (ctx->reg_val_types[index] >> (reg * 3)) & 7; +} + +/* Simply emit the instruction if the JIT memory space has been allocated */ +#define emit_instr(ctx, func, ...) \ +do { \ + if ((ctx)->target != NULL) { \ + u32 *p = &(ctx)->target[ctx->idx]; \ + uasm_i_##func(&p, ##__VA_ARGS__); \ + } \ + (ctx)->idx++; \ +} while (0) + +static unsigned int j_target(struct jit_ctx *ctx, int target_idx) +{ + unsigned long target_va, base_va; + unsigned int r; + + if (!ctx->target) + return 0; + + base_va = (unsigned long)ctx->target; + target_va = base_va + (ctx->offsets[target_idx] & ~OFFSETS_B_CONV); + + if ((base_va & ~0x0ffffffful) != (target_va & ~0x0ffffffful)) + return (unsigned int)-1; + r = target_va & 0x0ffffffful; + return r; +} + +/* Compute the immediate value for PC-relative branches. */ +static u32 b_imm(unsigned int tgt, struct jit_ctx *ctx) +{ + if (!ctx->gen_b_offsets) + return 0; + + /* + * We want a pc-relative branch. tgt is the instruction offset + * we want to jump to. + + * Branch on MIPS: + * I: target_offset <- sign_extend(offset) + * I+1: PC += target_offset (delay slot) + * + * ctx->idx currently points to the branch instruction + * but the offset is added to the delay slot so we need + * to subtract 4. + */ + return (ctx->offsets[tgt] & ~OFFSETS_B_CONV) - + (ctx->idx * 4) - 4; +} + +int bpf_jit_enable __read_mostly; + +enum which_ebpf_reg { + src_reg, + src_reg_no_fp, + dst_reg, + dst_reg_fp_ok +}; + +/* + * For eBPF, the register mapping naturally falls out of the + * requirements of eBPF and the MIPS n64 ABI. We don't maintain a + * separate frame pointer, so BPF_REG_10 relative accesses are + * adjusted to be $sp relative. + */ +int ebpf_to_mips_reg(struct jit_ctx *ctx, const struct bpf_insn *insn, + enum which_ebpf_reg w) +{ + int ebpf_reg = (w == src_reg || w == src_reg_no_fp) ? + insn->src_reg : insn->dst_reg; + + switch (ebpf_reg) { + case BPF_REG_0: + return MIPS_R_V0; + case BPF_REG_1: + return MIPS_R_A0; + case BPF_REG_2: + return MIPS_R_A1; + case BPF_REG_3: + return MIPS_R_A2; + case BPF_REG_4: + return MIPS_R_A3; + case BPF_REG_5: + return MIPS_R_A4; + case BPF_REG_6: + ctx->flags |= EBPF_SAVE_S0; + return MIPS_R_S0; + case BPF_REG_7: + ctx->flags |= EBPF_SAVE_S1; + return MIPS_R_S1; + case BPF_REG_8: + ctx->flags |= EBPF_SAVE_S2; + return MIPS_R_S2; + case BPF_REG_9: + ctx->flags |= EBPF_SAVE_S3; + return MIPS_R_S3; + case BPF_REG_10: + if (w == dst_reg || w == src_reg_no_fp) + goto bad_reg; + ctx->flags |= EBPF_SEEN_FP; + /* + * Needs special handling, return something that + * cannot be clobbered just in case. + */ + return MIPS_R_ZERO; + case BPF_REG_AX: + return MIPS_R_T4; + default: +bad_reg: + WARN(1, "Illegal bpf reg: %d\n", ebpf_reg); + return -EINVAL; + } +} +/* + * eBPF stack frame will be something like: + * + * Entry $sp ------> +--------------------------------+ + * | $ra (optional) | + * +--------------------------------+ + * | $s0 (optional) | + * +--------------------------------+ + * | $s1 (optional) | + * +--------------------------------+ + * | $s2 (optional) | + * +--------------------------------+ + * | $s3 (optional) | + * +--------------------------------+ + * | $s4 (optional) | + * +--------------------------------+ + * | tmp-storage (if $ra saved) | + * $sp + tmp_offset --> +--------------------------------+ <--BPF_REG_10 + * | BPF_REG_10 relative storage | + * | MAX_BPF_STACK (optional) | + * | . | + * | . | + * | . | + * $sp --------> +--------------------------------+ + * + * If BPF_REG_10 is never referenced, then the MAX_BPF_STACK sized + * area is not allocated. + */ +static int gen_int_prologue(struct jit_ctx *ctx) +{ + int stack_adjust = 0; + int store_offset; + int locals_size; + + if (ctx->flags & EBPF_SAVE_RA) + /* + * If RA we are doing a function call and may need + * extra 8-byte tmp area. + */ + stack_adjust += 16; + if (ctx->flags & EBPF_SAVE_S0) + stack_adjust += 8; + if (ctx->flags & EBPF_SAVE_S1) + stack_adjust += 8; + if (ctx->flags & EBPF_SAVE_S2) + stack_adjust += 8; + if (ctx->flags & EBPF_SAVE_S3) + stack_adjust += 8; + if (ctx->flags & EBPF_SAVE_S4) + stack_adjust += 8; + + BUILD_BUG_ON(MAX_BPF_STACK & 7); + locals_size = (ctx->flags & EBPF_SEEN_FP) ? MAX_BPF_STACK : 0; + + stack_adjust += locals_size; + ctx->tmp_offset = locals_size; + + ctx->stack_size = stack_adjust; + + /* + * First instruction initializes the tail call count (TCC). + * On tail call we skip this instruction, and the TCC is + * passed in $v1 from the caller. + */ + emit_instr(ctx, daddiu, MIPS_R_V1, MIPS_R_ZERO, MAX_TAIL_CALL_CNT); + if (stack_adjust) + emit_instr(ctx, daddiu, MIPS_R_SP, MIPS_R_SP, -stack_adjust); + else + return 0; + + store_offset = stack_adjust - 8; + + if (ctx->flags & EBPF_SAVE_RA) { + emit_instr(ctx, sd, MIPS_R_RA, store_offset, MIPS_R_SP); + store_offset -= 8; + } + if (ctx->flags & EBPF_SAVE_S0) { + emit_instr(ctx, sd, MIPS_R_S0, store_offset, MIPS_R_SP); + store_offset -= 8; + } + if (ctx->flags & EBPF_SAVE_S1) { + emit_instr(ctx, sd, MIPS_R_S1, store_offset, MIPS_R_SP); |