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diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h
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+/*
+ * bpf_jit64.h: BPF JIT compiler for PPC64
+ *
+ * Copyright 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
+ * IBM Corporation
+ *
+ * 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.
+ */
+#ifndef _BPF_JIT64_H
+#define _BPF_JIT64_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)
+
+#ifndef __ASSEMBLY__
+
+/* 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 */
+static const int b2p[] = {
+ /* function return value */
+ [BPF_REG_0] = 8,
+ /* function arguments */
+ [BPF_REG_1] = 3,
+ [BPF_REG_2] = 4,
+ [BPF_REG_3] = 5,
+ [BPF_REG_4] = 6,
+ [BPF_REG_5] = 7,
+ /* non volatile registers */
+ [BPF_REG_6] = 27,
+ [BPF_REG_7] = 28,
+ [BPF_REG_8] = 29,
+ [BPF_REG_9] = 30,
+ /* frame pointer aka BPF_REG_10 */
+ [BPF_REG_FP] = 31,
+ /* eBPF jit internal registers */
+ [BPF_REG_AX] = 2,
+ [TMP_REG_1] = 9,
+ [TMP_REG_2] = 10
+};
+
+/* PPC NVR range -- update this if we ever use NVRs below r27 */
+#define BPF_PPC_NVR_MIN 27
+
+/*
+ * WARNING: These can use TMP_REG_2 if the offset is not at word boundary,
+ * so ensure that it isn't in use already.
+ */
+#define PPC_BPF_LL(r, base, i) do { \
+ if ((i) % 4) { \
+ PPC_LI(b2p[TMP_REG_2], (i)); \
+ PPC_LDX(r, base, b2p[TMP_REG_2]); \
+ } else \
+ PPC_LD(r, base, i); \
+ } while(0)
+#define PPC_BPF_STL(r, base, i) do { \
+ if ((i) % 4) { \
+ PPC_LI(b2p[TMP_REG_2], (i)); \
+ PPC_STDX(r, base, b2p[TMP_REG_2]); \
+ } else \
+ PPC_STD(r, base, i); \
+ } while(0)
+#define PPC_BPF_STLU(r, base, i) do { PPC_STDU(r, base, i); } while(0)
+
+#define SEEN_FUNC 0x1000 /* might call external helpers */
+#define SEEN_STACK 0x2000 /* uses BPF stack */
+#define SEEN_TAILCALL 0x4000 /* 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-r10 and r27-r31)
+ * - rest of the bits can be used to track other
+ * things -- for now, we use bits 16 to 23
+ * encoded in SEEN_* macros above
+ */
+ unsigned int seen;
+ unsigned int idx;
+ unsigned int stack_size;
+};
+
+#endif /* !__ASSEMBLY__ */
+
+#endif