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authorChristophe Leroy <christophe.leroy@csgroup.eu>2021-03-22 16:37:46 +0000
committerMichael Ellerman <mpe@ellerman.id.au>2021-04-03 21:22:20 +1100
commit6944caad78fc4de4ecd0364bbc9715b62b020965 (patch)
treeb02e4bc830b0778067a8710e71911bf3495035f2 /arch/powerpc/net/bpf_jit_comp.c
parentc7393a71eb1abdda7e3a3ef798bae60de11540ec (diff)
downloadlinux-6944caad78fc4de4ecd0364bbc9715b62b020965.tar.gz
powerpc/bpf: Remove classical BPF support for PPC32
At the time being, PPC32 has Classical BPF support.

The test_bpf module exhibits some failure:

	test_bpf: #298 LD_IND byte frag jited:1 ret 202 != 66 FAIL (1 times)
	test_bpf: #299 LD_IND halfword frag jited:1 ret 51958 != 17220 FAIL (1 times)
	test_bpf: #301 LD_IND halfword mixed head/frag jited:1 ret 51958 != 1305 FAIL (1 times)
	test_bpf: #303 LD_ABS byte frag jited:1 ret 202 != 66 FAIL (1 times)
	test_bpf: #304 LD_ABS halfword frag jited:1 ret 51958 != 17220 FAIL (1 times)
	test_bpf: #306 LD_ABS halfword mixed head/frag jited:1 ret 51958 != 1305 FAIL (1 times)

	test_bpf: Summary: 371 PASSED, 7 FAILED, [119/366 JIT'ed]

Fixing this is not worth the effort. Instead, remove support for
classical BPF and prepare for adding Extended BPF support instead.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fbc3e4fcc9c8f6131d6c705212530b2aa50149ee.1616430991.git.christophe.leroy@csgroup.eu
Diffstat (limited to 'arch/powerpc/net/bpf_jit_comp.c')
-rw-r--r--arch/powerpc/net/bpf_jit_comp.c683
1 files changed, 0 insertions, 683 deletions
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
deleted file mode 100644
index e809cb5a1631..000000000000
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ /dev/null
@@ -1,683 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/* bpf_jit_comp.c: BPF JIT compiler
- *
- * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
- *
- * Based on the x86 BPF compiler, by Eric Dumazet (eric.dumazet@gmail.com)
- * Ported to ppc32 by Denis Kirjanov <kda@linux-powerpc.org>
- */
-#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 "bpf_jit32.h"
-
-static inline void bpf_flush_icache(void *start, void *end)
-{
-	smp_wmb();
-	flush_icache_range((unsigned long)start, (unsigned long)end);
-}
-
-static void bpf_jit_build_prologue(struct bpf_prog *fp, u32 *image,
-				   struct codegen_context *ctx)
-{
-	int i;
-	const struct sock_filter *filter = fp->insns;
-
-	if (ctx->seen & (SEEN_MEM | SEEN_DATAREF)) {
-		/* Make stackframe */
-		if (ctx->seen & SEEN_DATAREF) {
-			/* If we call any helpers (for loads), save LR */
-			EMIT(PPC_INST_MFLR | __PPC_RT(R0));
-			PPC_BPF_STL(0, 1, PPC_LR_STKOFF);
-
-			/* Back up non-volatile regs. */
-			PPC_BPF_STL(r_D, 1, -(REG_SZ*(32-r_D)));
-			PPC_BPF_STL(r_HL, 1, -(REG_SZ*(32-r_HL)));
-		}
-		if (ctx->seen & SEEN_MEM) {
-			/*
-			 * Conditionally save regs r15-r31 as some will be used
-			 * for M[] data.
-			 */
-			for (i = r_M; i < (r_M+16); i++) {
-				if (ctx->seen & (1 << (i-r_M)))
-					PPC_BPF_STL(i, 1, -(REG_SZ*(32-i)));
-			}
-		}
-		PPC_BPF_STLU(1, 1, -BPF_PPC_STACKFRAME);
-	}
-
-	if (ctx->seen & SEEN_DATAREF) {
-		/*
-		 * If this filter needs to access skb data,
-		 * prepare r_D and r_HL:
-		 *  r_HL = skb->len - skb->data_len
-		 *  r_D	 = skb->data
-		 */
-		PPC_LWZ_OFFS(r_scratch1, r_skb, offsetof(struct sk_buff,
-							 data_len));
-		PPC_LWZ_OFFS(r_HL, r_skb, offsetof(struct sk_buff, len));
-		EMIT(PPC_RAW_SUB(r_HL, r_HL, r_scratch1));
-		PPC_LL_OFFS(r_D, r_skb, offsetof(struct sk_buff, data));
-	}
-
-	if (ctx->seen & SEEN_XREG) {
-		/*
-		 * TODO: Could also detect whether first instr. sets X and
-		 * avoid this (as below, with A).
-		 */
-		EMIT(PPC_RAW_LI(r_X, 0));
-	}
-
-	/* make sure we dont leak kernel information to user */
-	if (bpf_needs_clear_a(&filter[0]))
-		EMIT(PPC_RAW_LI(r_A, 0));
-}
-
-static void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
-{
-	int i;
-
-	if (ctx->seen & (SEEN_MEM | SEEN_DATAREF)) {
-		EMIT(PPC_RAW_ADDI(1, 1, BPF_PPC_STACKFRAME));
-		if (ctx->seen & SEEN_DATAREF) {
-			PPC_BPF_LL(0, 1, PPC_LR_STKOFF);
-			EMIT(PPC_RAW_MTLR(0));
-			PPC_BPF_LL(r_D, 1, -(REG_SZ*(32-r_D)));
-			PPC_BPF_LL(r_HL, 1, -(REG_SZ*(32-r_HL)));
-		}
-		if (ctx->seen & SEEN_MEM) {
-			/* Restore any saved non-vol registers */
-			for (i = r_M; i < (r_M+16); i++) {
-				if (ctx->seen & (1 << (i-r_M)))
-					PPC_BPF_LL(i, 1, -(REG_SZ*(32-i)));
-			}
-		}
-	}
-	/* The RETs have left a return value in R3. */
-
-	EMIT(PPC_RAW_BLR());
-}
-
-#define CHOOSE_LOAD_FUNC(K, func) \
-	((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset)
-
-/* Assemble the body code between the prologue & epilogue. */
-static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
-			      struct codegen_context *ctx,
-			      unsigned int *addrs)
-{
-	const struct sock_filter *filter = fp->insns;
-	int flen = fp->len;
-	u8 *func;
-	unsigned int true_cond;
-	int i;
-
-	/* Start of epilogue code */
-	unsigned int exit_addr = addrs[flen];
-
-	for (i = 0; i < flen; i++) {
-		unsigned int K = filter[i].k;
-		u16 code = bpf_anc_helper(&filter[i]);
-
-		/*
-		 * addrs[] maps a BPF bytecode address into a real offset from
-		 * the start of the body code.
-		 */
-		addrs[i] = ctx->idx * 4;
-
-		switch (code) {
-			/*** ALU ops ***/
-		case BPF_ALU | BPF_ADD | BPF_X: /* A += X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_ADD(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_ADD | BPF_K: /* A += K; */
-			if (!K)
-				break;
-			EMIT(PPC_RAW_ADDI(r_A, r_A, IMM_L(K)));
-			if (K >= 32768)
-				EMIT(PPC_RAW_ADDIS(r_A, r_A, IMM_HA(K)));
-			break;
-		case BPF_ALU | BPF_SUB | BPF_X: /* A -= X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_SUB(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_SUB | BPF_K: /* A -= K */
-			if (!K)
-				break;
-			EMIT(PPC_RAW_ADDI(r_A, r_A, IMM_L(-K)));
-			if (K >= 32768)
-				EMIT(PPC_RAW_ADDIS(r_A, r_A, IMM_HA(-K)));
-			break;
-		case BPF_ALU | BPF_MUL | BPF_X: /* A *= X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_MULW(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_MUL | BPF_K: /* A *= K */
-			if (K < 32768)
-				EMIT(PPC_RAW_MULI(r_A, r_A, K));
-			else {
-				PPC_LI32(r_scratch1, K);
-				EMIT(PPC_RAW_MULW(r_A, r_A, r_scratch1));
-			}
-			break;
-		case BPF_ALU | BPF_MOD | BPF_X: /* A %= X; */
-		case BPF_ALU | BPF_DIV | BPF_X: /* A /= X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_CMPWI(r_X, 0));
-			if (ctx->pc_ret0 != -1) {
-				PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]);
-			} else {
-				PPC_BCC_SHORT(COND_NE, (ctx->idx*4)+12);
-				EMIT(PPC_RAW_LI(r_ret, 0));
-				PPC_JMP(exit_addr);
-			}
-			if (code == (BPF_ALU | BPF_MOD | BPF_X)) {
-				EMIT(PPC_RAW_DIVWU(r_scratch1, r_A, r_X));
-				EMIT(PPC_RAW_MULW(r_scratch1, r_X, r_scratch1));
-				EMIT(PPC_RAW_SUB(r_A, r_A, r_scratch1));
-			} else {
-				EMIT(PPC_RAW_DIVWU(r_A, r_A, r_X));
-			}
-			break;
-		case BPF_ALU | BPF_MOD | BPF_K: /* A %= K; */
-			PPC_LI32(r_scratch2, K);
-			EMIT(PPC_RAW_DIVWU(r_scratch1, r_A, r_scratch2));
-			EMIT(PPC_RAW_MULW(r_scratch1, r_scratch2, r_scratch1));
-			EMIT(PPC_RAW_SUB(r_A, r_A, r_scratch1));
-			break;
-		case BPF_ALU | BPF_DIV | BPF_K: /* A /= K */
-			if (K == 1)
-				break;
-			PPC_LI32(r_scratch1, K);
-			EMIT(PPC_RAW_DIVWU(r_A, r_A, r_scratch1));
-			break;
-		case BPF_ALU | BPF_AND | BPF_X:
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_AND(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_AND | BPF_K:
-			if (!IMM_H(K))
-				EMIT(PPC_RAW_ANDI(r_A, r_A, K));
-			else {
-				PPC_LI32(r_scratch1, K);
-				EMIT(PPC_RAW_AND(r_A, r_A, r_scratch1));
-			}
-			break;
-		case BPF_ALU | BPF_OR | BPF_X:
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_OR(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_OR | BPF_K:
-			if (IMM_L(K))
-				EMIT(PPC_RAW_ORI(r_A, r_A, IMM_L(K)));
-			if (K >= 65536)
-				EMIT(PPC_RAW_ORIS(r_A, r_A, IMM_H(K)));
-			break;
-		case BPF_ANC | SKF_AD_ALU_XOR_X:
-		case BPF_ALU | BPF_XOR | BPF_X: /* A ^= X */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_XOR(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_XOR | BPF_K: /* A ^= K */
-			if (IMM_L(K))
-				EMIT(PPC_RAW_XORI(r_A, r_A, IMM_L(K)));
-			if (K >= 65536)
-				EMIT(PPC_RAW_XORIS(r_A, r_A, IMM_H(K)));
-			break;
-		case BPF_ALU | BPF_LSH | BPF_X: /* A <<= X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_SLW(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_LSH | BPF_K:
-			if (K == 0)
-				break;
-			else
-				EMIT(PPC_RAW_SLWI(r_A, r_A, K));
-			break;
-		case BPF_ALU | BPF_RSH | BPF_X: /* A >>= X; */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_SRW(r_A, r_A, r_X));
-			break;
-		case BPF_ALU | BPF_RSH | BPF_K: /* A >>= K; */
-			if (K == 0)
-				break;
-			else
-				EMIT(PPC_RAW_SRWI(r_A, r_A, K));
-			break;
-		case BPF_ALU | BPF_NEG:
-			EMIT(PPC_RAW_NEG(r_A, r_A));
-			break;
-		case BPF_RET | BPF_K:
-			PPC_LI32(r_ret, K);
-			if (!K) {
-				if (ctx->pc_ret0 == -1)
-					ctx->pc_ret0 = i;
-			}
-			/*
-			 * If this isn't the very last instruction, branch to
-			 * the epilogue if we've stuff to clean up.  Otherwise,
-			 * if there's nothing to tidy, just return.  If we /are/
-			 * the last instruction, we're about to fall through to
-			 * the epilogue to return.
-			 */
-			if (i != flen - 1) {
-				/*
-				 * Note: 'seen' is properly valid only on pass
-				 * #2.	Both parts of this conditional are the
-				 * same instruction size though, meaning the
-				 * first pass will still correctly determine the
-				 * code size/addresses.
-				 */
-				if (ctx->seen)
-					PPC_JMP(exit_addr);
-				else
-					EMIT(PPC_RAW_BLR());
-			}
-			break;
-		case BPF_RET | BPF_A:
-			EMIT(PPC_RAW_MR(r_ret, r_A));
-			if (i != flen - 1) {
-				if (ctx->seen)
-					PPC_JMP(exit_addr);
-				else
-					EMIT(PPC_RAW_BLR());
-			}
-			break;
-		case BPF_MISC | BPF_TAX: /* X = A */
-			EMIT(PPC_RAW_MR(r_X, r_A));
-			break;
-		case BPF_MISC | BPF_TXA: /* A = X */
-			ctx->seen |= SEEN_XREG;
-			EMIT(PPC_RAW_MR(r_A, r_X));
-			break;
-
-			/*** Constant loads/M[] access ***/
-		case BPF_LD | BPF_IMM: /* A = K */
-			PPC_LI32(r_A, K);
-			break;
-		case BPF_LDX | BPF_IMM: /* X = K */
-			PPC_LI32(r_X, K);
-			break;
-		case BPF_LD | BPF_MEM: /* A = mem[K] */
-			EMIT(PPC_RAW_MR(r_A, r_M + (K & 0xf)));
-			ctx->seen |= SEEN_MEM | (1<<(K & 0xf));
-			break;
-		case BPF_LDX | BPF_MEM: /* X = mem[K] */
-			EMIT(PPC_RAW_MR(r_X, r_M + (K & 0xf)));
-			ctx->seen |= SEEN_MEM | (1<<(K & 0xf));
-			break;
-		case BPF_ST: /* mem[K] = A */
-			EMIT(PPC_RAW_MR(r_M + (K & 0xf), r_A));
-			ctx->seen |= SEEN_MEM | (1<<(K & 0xf));
-			break;
-		case BPF_STX: /* mem[K] = X */
-			EMIT(PPC_RAW_MR(r_M + (K & 0xf), r_X));
-			ctx->seen |= SEEN_XREG | SEEN_MEM | (1<<(K & 0xf));
-			break;
-		case BPF_LD | BPF_W | BPF_LEN: /*	A = skb->len; */
-			BUILD_BUG_ON(sizeof_field(struct sk_buff, len) != 4);
-			PPC_LWZ_OFFS(r_A, r_skb, offsetof(struct sk_buff, len));
-			break;
-		case BPF_LDX | BPF_W | BPF_ABS: /* A = *((u32 *)(seccomp_data + K)); */
-			PPC_LWZ_OFFS(r_A, r_skb, K);
-			break;
-		case BPF_LDX | BPF_W | BPF_LEN: /* X = skb->len; */
-			PPC_LWZ_OFFS(r_X, r_skb, offsetof(struct sk_buff, len));
-			break;
-
-			/*** Ancillary info loads ***/
-		case BPF_ANC | SKF_AD_PROTOCOL: /* A = ntohs(skb->protocol); */
-			BUILD_BUG_ON(sizeof_field(struct sk_buff,
-						  protocol) != 2);
-			PPC_NTOHS_OFFS(r_A, r_skb, offsetof(struct sk_buff,
-							    protocol));
-			break;
-		case BPF_ANC | SKF_AD_IFINDEX:
-		case BPF_ANC | SKF_AD_HATYPE:
-			BUILD_BUG_ON(sizeof_field(struct net_device,
-						ifindex) != 4);
-			BUILD_BUG_ON(sizeof_field(struct net_device,
-						type) != 2);
-			PPC_LL_OFFS(r_scratch1, r_skb, offsetof(struct sk_buff,
-								dev));
-			EMIT(PPC_RAW_CMPDI(r_scratch1, 0));
-			if (ctx->pc_ret0 != -1) {
-				PPC_BCC(COND_EQ, addrs[ctx->pc_ret0]);
-			} else {
-				/* Exit, returning 0; first pass hits here. */
-				PPC_BCC_SHORT(COND_NE, ctx->idx * 4 + 12);
-				EMIT(PPC_RAW_LI(r_ret, 0));
-				PPC_JMP(exit_addr);
-			}
-			if (code == (BPF_ANC | SKF_AD_IFINDEX)) {
-				PPC_LWZ_OFFS(r_A, r_scratch1,
-				     offsetof(struct net_device, ifindex));
-			} else {
-				PPC_LHZ_OFFS(r_A, r_scratch1,
-				     offsetof(struct net_device, type));
-			}
-
-			break;
-		case BPF_ANC | SKF_AD_MARK:
-			BUILD_BUG_ON(sizeof_field(struct sk_buff, mark) != 4);
-			PPC_LWZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
-							  mark));
-			break;
-		case BPF_ANC | SKF_AD_RXHASH:
-			BUILD_BUG_ON(sizeof_field(struct sk_buff, hash) != 4);
-			PPC_LWZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
-							  hash));
-			break;
-		case BPF_ANC | SKF_AD_VLAN_TAG:
-			BUILD_BUG_ON(sizeof_field(struct sk_buff, vlan_tci) != 2);
-
-			PPC_LHZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
-							  vlan_tci));
-			break;
-		case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT:
-			PPC_LBZ_OFFS(r_A, r_skb, PKT_VLAN_PRESENT_OFFSET());
-			if (PKT_VLAN_PRESENT_BIT)
-				EMIT(PPC_RAW_SRWI(r_A, r_A, PKT_VLAN_PRESENT_BIT));
-			if (PKT_VLAN_PRESENT_BIT < 7)
-				EMIT(PPC_RAW_ANDI(r_A, r_A, 1));
-			break;
-		case BPF_ANC | SKF_AD_QUEUE:
-			BUILD_BUG_ON(sizeof_field(struct sk_buff,
-						  queue_mapping) != 2);
-			PPC_LHZ_OFFS(r_A, r_skb, offsetof(struct sk_buff,
-							  queue_mapping));
-			break;
-		case BPF_ANC | SKF_AD_PKTTYPE:
-			PPC_LBZ_OFFS(r_A, r_skb, PKT_TYPE_OFFSET());
-			EMIT(PPC_RAW_ANDI(r_A, r_A, PKT_TYPE_MAX));
-			EMIT(PPC_RAW_SRWI(r_A, r_A, 5));
-			break;
-		case BPF_ANC | SKF_AD_CPU:
-			PPC_BPF_LOAD_CPU(r_A);
-			break;
-			/*** Absolute loads from packet header/data ***/
-		case BPF_LD | BPF_W | BPF_ABS:
-			func = CHOOSE_LOAD_FUNC(K, sk_load_word);
-			goto common_load;
-		case BPF_LD | BPF_H | BPF_ABS:
-			func = CHOOSE_LOAD_FUNC(K, sk_load_half);
-			goto common_load;
-		case BPF_LD | BPF_B | BPF_ABS:
-			func = CHOOSE_LOAD_FUNC(K, sk_load_byte);
-		common_load:
-			/* Load from [K]. */
-			ctx->seen |= SEEN_DATAREF;
-			PPC_FUNC_ADDR(r_scratch1, func);
-			EMIT(PPC_RAW_MTLR(r_scratch1));
-			PPC_LI32(r_addr, K);
-			EMIT(PPC_RAW_BLRL());
-			/*
-			 * Helper returns 'lt' condition on error, and an
-			 * appropriate return value in r3
-			 */
-			PPC_BCC(COND_LT, exit_addr);
-			break;
-
-			/*** Indirect loads from packet header/data ***/
-		case BPF_LD | BPF_W | BPF_IND:
-			func = sk_load_word;
-			goto common_load_ind;
-		case BPF_LD | BPF_H | BPF_IND:
-			func = sk_load_half;
-			goto common_load_ind;
-		case BPF_LD | BPF_B | BPF_IND:
-			func = sk_load_byte;
-		common_load_ind:
-			/*
-			 * Load from [X + K].  Negative offsets are tested for
-			 * in the helper functions.
-			 */
-			ctx->seen |= SEEN_DATAREF | SEEN_XREG;
-			PPC_FUNC_ADDR(r_scratch1, func);
-			EMIT(PPC_RAW_MTLR(r_scratch1));
-			EMIT(PPC_RAW_ADDI(r_addr, r_X, IMM_L(K)));
-			if (K >= 32768)
-				EMIT(PPC_RAW_ADDIS(r_addr, r_addr, IMM_HA(K)));
-			EMIT(PPC_RAW_BLRL());
-			/* If error, cr0.LT set */
-			PPC_BCC(COND_LT, exit_addr);
-			break;
-
-		case BPF_LDX | BPF_B | BPF_MSH:
-			func = CHOOSE_LOAD_FUNC(K, sk_load_byte_msh);
-			goto common_load;
-			break;
-
-			/*** Jump and branches ***/
-		case BPF_JMP | BPF_JA:
-			if (K != 0)
-				PPC_JMP(addrs[i + 1 + K]);
-			break;
-
-		case BPF_JMP | BPF_JGT | BPF_K:
-		case BPF_JMP | BPF_JGT | BPF_X:
-			true_cond = COND_GT;
-			goto cond_branch;
-		case BPF_JMP | BPF_JGE | BPF_K:
-		case BPF_JMP | BPF_JGE | BPF_X:
-			true_cond = COND_GE;
-			goto cond_branch;
-		case BPF_JMP | BPF_JEQ | BPF_K:
-		case BPF_JMP | BPF_JEQ | BPF_X:
-			true_cond = COND_EQ;
-			goto cond_branch;
-		case BPF_JMP | BPF_JSET | BPF_K:
-		case BPF_JMP | BPF_JSET | BPF_X:
-			true_cond = COND_NE;
-		cond_branch:
-			/* same targets, can avoid doing the test :) */
-			if (filter[i].jt == filter[i].jf) {
-				if (filter[i].jt > 0)
-					PPC_JMP(addrs[i + 1 + filter[i].jt]);
-				break;
-			}
-
-			switch (code) {
-			case BPF_JMP | BPF_JGT | BPF_X:
-			case BPF_JMP | BPF_JGE | BPF_X:
-			case BPF_JMP | BPF_JEQ | BPF_X:
-				ctx->seen |= SEEN_XREG;
-				EMIT(PPC_RAW_CMPLW(r_A, r_X));
-				break;
-			case BPF_JMP | BPF_JSET | BPF_X:
-				ctx->seen |= SEEN_XREG;
-				EMIT(PPC_RAW_AND_DOT(r_scratch1, r_A, r_X));
-				break;
-			case BPF_JMP | BPF_JEQ | BPF_K:
-			case BPF_JMP | BPF_JGT | BPF_K:
-			case BPF_JMP | BPF_JGE | BPF_K:
-				if (K < 32768)
-					EMIT(PPC_RAW_CMPLWI(r_A, K));
-				else {
-					PPC_LI32(r_scratch1, K);
-					EMIT(PPC_RAW_CMPLW(r_A, r_scratch1));
-				}
-				break;
-			case BPF_JMP | BPF_JSET | BPF_K:
-				if (K < 32768)
-					/* PPC_ANDI is /only/ dot-form */
-					EMIT(PPC_RAW_ANDI(r_scratch1, r_A, K));
-				else {
-					PPC_LI32(r_scratch1, K);
-					EMIT(PPC_RAW_AND_DOT(r_scratch1, r_A,
-						    r_scratch1));
-				}
-				break;
-			}
-			/* Sometimes branches are constructed "backward", with
-			 * the false path being the branch and true path being
-			 * a fallthrough to the next instruction.
-			 */
-			if (filter[i].jt == 0)
-				/* Swap the sense of the branch */
-				PPC_BCC(true_cond ^ COND_CMP_TRUE,
-					addrs[i + 1 + filter[i].jf]);
-			else {
-				PPC_BCC(true_cond, addrs[i + 1 + filter[i].jt]);
-				if (filter[i].jf != 0)
-					PPC_JMP(addrs[i + 1 + filter[i].jf]);
-			}
-			break;
-		default:
-			/* The filter contains something cruel & unusual.
-			 * We don't handle it, but also there shouldn't be
-			 * anything missing from our list.
-			 */
-			if (printk_ratelimit())
-				pr_err("BPF filter opcode %04x (@%d) unsupported\n",
-				       filter[i].code, i);
-			return -ENOTSUPP;
-		}
-
-	}
-	/* Set end-of-body-code address for exit. */
-	addrs[i] = ctx->idx * 4;
-
-	return 0;
-}
-
-void bpf_jit_compile(struct bpf_prog *fp)
-{
-	unsigned int proglen;
-	unsigned int alloclen;
-	u32 *image = NULL;
-	u32 *code_base;
-	unsigned int *addrs;
-	struct codegen_context cgctx;
-	int pass;
-	int flen = fp->len;
-
-	if (!bpf_jit_enable)
-		return;
-
-	addrs = kcalloc(flen + 1, sizeof(*addrs), GFP_KERNEL);
-	if (addrs == NULL)
-		return;
-
-	/*
-	 * There are multiple assembly passes as the generated code will change
-	 * size as it settles down, figuring out the max branch offsets/exit
-	 * paths required.
-	 *
-	 * The range of standard conditional branches is +/- 32Kbytes.	Since
-	 * BPF_MAXINSNS = 4096, we can only jump from (worst case) start to
-	 * finish with 8 bytes/instruction.  Not feasible, so long jumps are
-	 * used, distinct from short branches.
-	 *
-	 * Current:
-	 *
-	 * For now, both branch types assemble to 2 words (short branches padded
-	 * with a NOP); this is less efficient, but assembly will always complete
-	 * after exactly 3 passes:
-	 *
-	 * First pass: No code buffer; Program is "faux-generated" -- no code
-	 * emitted but maximum size of output determined (and addrs[] filled
-	 * in).	 Also, we note whether we use M[], whether we use skb data, etc.
-	 * All generation choices assumed to be 'worst-case', e.g. branches all
-	 * far (2 instructions), return path code reduction not available, etc.
-	 *
-	 * Second pass: Code buffer allocated with size determined previously.
-	 * Prologue generated to support features we have seen used.  Exit paths
-	 * determined and addrs[] is filled in again, as code may be slightly
-	 * smaller as a result.
-	 *
-	 * Third pass: Code generated 'for real', and branch destinations
-	 * determined from now-accurate addrs[] map.
-	 *
-	 * Ideal:
-	 *
-	 * If we optimise this, near branches will be shorter.	On the
-	 * first assembly pass, we should err on the side of caution and
-	 * generate the biggest code.  On subsequent passes, branches will be
-	 * generated short or long and code size will reduce.  With smaller
-	 * code, more branches may fall into the short category, and code will
-	 * reduce more.
-	 *
-	 * Finally, if we see one pass generate code the same size as the
-	 * previous pass we have converged and should now generate code for
-	 * real.  Allocating at the end will also save the memory that would
-	 * otherwise be wasted by the (small) current code shrinkage.
-	 * Preferably, we should do a small number of passes (e.g. 5) and if we
-	 * haven't converged by then, get impatient and force code to generate
-	 * as-is, even if the odd branch would be left long.  The chances of a
-	 * long jump are tiny with all but the most enormous of BPF filter
-	 * inputs, so we should usually converge on the third pass.
-	 */
-
-	cgctx.idx = 0;
-	cgctx.seen = 0;
-	cgctx.pc_ret0 = -1;
-	/* Scouting faux-generate pass 0 */
-	if (bpf_jit_build_body(fp, 0, &cgctx, addrs))
-		/* We hit something illegal or unsupported. */
-		goto out;
-
-	/*
-	 * 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(fp, 0, &cgctx);
-	bpf_jit_build_epilogue(0, &cgctx);
-
-	proglen = cgctx.idx * 4;
-	alloclen = proglen + FUNCTION_DESCR_SIZE;
-	image = module_alloc(alloclen);
-	if (!image)
-		goto out;
-
-	code_base = image + (FUNCTION_DESCR_SIZE/4);
-
-	/* Code generation passes 1-2 */
-	for (pass = 1; pass < 3; pass++) {
-		/* Now build the prologue, body code & epilogue for real. */
-		cgctx.idx = 0;
-		bpf_jit_build_prologue(fp, code_base, &cgctx);
-		bpf_jit_build_body(fp, code_base, &cgctx, 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);
-
-	bpf_flush_icache(code_base, code_base + (proglen/4));
-
-#ifdef CONFIG_PPC64
-	/* 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;
-
-out:
-	kfree(addrs);
-	return;
-}
-
-void bpf_jit_free(struct bpf_prog *fp)
-{
-	if (fp->jited)
-		module_memfree(fp->bpf_func);
-
-	bpf_prog_unlock_free(fp);
-}