1 files changed, 112 insertions, 0 deletions
diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h
new file mode 100644
index 000000000..61ed9a4b2
--- /dev/null
+++ b/arch/powerpc/net/bpf_jit64.h
@@ -0,0 +1,112 @@
+/*
+ * 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