[RFC PATCH 0/6] eBPF JIT for PPC64

[RFC PATCH 0/6] eBPF JIT for PPC64

[Naveen N. Rao]

Implement extended BPF JIT for ppc64. We retain the classic BPF JIT for
ppc32 and move ppc64 BE/LE to use the new JIT. Classic BPF filters will
be converted to extended BPF (see convert_filter()) and JIT'ed with the
new compiler.

Most of the existing macros are retained and fixed/enhanced where
appropriate. Patches 1-4 are geared towards this.

Patch 5 breaks out the classic BPF JIT specifics into a separate
bpf_jit32.h header file, while retaining all the generic instruction
macros in bpf_jit.h. Most of these macros can potentially be generalized
and moved to more common code (tagged with a TODO in patch 6).

Patch 6 implements eBPF JIT for ppc64.

This is still *early* *RFC* and there are still a few instruction
classes to be JIT'ed. I am posting this in advance so as to get early
feedback. Kindly review the same and if possible, try it out and let me
know how it goes!


- Naveen

Naveen N. Rao (6):
  ppc: bpf/jit: Fix/enhance 32-bit Load Immediate implementation
  ppc: bpf/jit: Optimize 64-bit Immediate loads
  ppc: bpf/jit: Introduce rotate immediate instructions
  ppc: bpf/jit: A few cleanups
  ppc: bpf/jit: Isolate classic BPF JIT specifics into a separate header
  ppc: ebpf/jit: Implement JIT compiler for extended BPF

 arch/powerpc/include/asm/ppc-opcode.h |  21 +-
 arch/powerpc/net/Makefile             |   4 +
 arch/powerpc/net/bpf_jit.h            | 251 +++++------
 arch/powerpc/net/bpf_jit32.h          | 140 ++++++
 arch/powerpc/net/bpf_jit64.h          |  58 +++
 arch/powerpc/net/bpf_jit_asm.S        |   2 +-
 arch/powerpc/net/bpf_jit_comp.c       |  10 +-
 arch/powerpc/net/bpf_jit_comp64.c     | 828 ++++++++++++++++++++++++++++++++++
 8 files changed, 1163 insertions(+), 151 deletions(-)
 create mode 100644 arch/powerpc/net/bpf_jit32.h
 create mode 100644 arch/powerpc/net/bpf_jit64.h
 create mode 100644 arch/powerpc/net/bpf_jit_comp64.c

-- 
2.7.4

[RFC PATCH 1/6] ppc: bpf/jit: Fix/enhance 32-bit Load Immediate implementation

[Naveen N. Rao]

The existing LI32() macro can sometimes result in a sign-extended 32-bit
load that does not clear the top 32-bits properly. As an example,
loading 0x7fffffff results in the register containing
0xffffffff7fffffff. While this does not impact classic BPF JIT
implementation (since that only uses the lower word for all operations),
we would like to share this macro between classic BPF JIT and extended
BPF JIT, wherein the entire 64-bit value in the register matters. Fix
this by first doing a shifted LI followed by ORI.

An additional optimization is with loading values between -32768 to -1,
where we now only need a single LI.

The new implementation now generates the same or less number of
instructions.

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/net/bpf_jit.h | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 889fd19..a9882db 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -232,10 +232,17 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 					     (((cond) & 0x3ff) << 16) |	      \
 					     (((dest) - (ctx->idx * 4)) &     \
 					      0xfffc))
-#define PPC_LI32(d, i)		do { PPC_LI(d, IMM_L(i));		      \
-		if ((u32)(uintptr_t)(i) >= 32768) {			      \
-			PPC_ADDIS(d, d, IMM_HA(i));			      \
+/* Sign-extended 32-bit immediate load */
+#define PPC_LI32(d, i)		do {					      \
+		if ((int)(uintptr_t)(i) >= -32768 &&			      \
+				(int)(uintptr_t)(i) < 32768)		      \
+			PPC_LI(d, i);					      \
+		else {							      \
+			PPC_LIS(d, IMM_H(i));				      \
+			if (IMM_L(i))					      \
+				PPC_ORI(d, d, IMM_L(i));		      \
 		} } while(0)
+
 #define PPC_LI64(d, i)		do {					      \
 		if (!((uintptr_t)(i) & 0xffffffff00000000ULL))		      \
 			PPC_LI32(d, i);					      \
-- 
2.7.4

[RFC PATCH 2/6] ppc: bpf/jit: Optimize 64-bit Immediate loads

[Naveen N. Rao]

Similar to the LI32() optimization, if the value can be represented
in 32-bits, use LI32(). Also handle loading a few specific forms of
immediate values in an optimum manner.

While at it, remove the semicolon at the end of the macro!

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/net/bpf_jit.h | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index a9882db..4c1e055 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -244,20 +244,25 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 		} } while(0)
 
 #define PPC_LI64(d, i)		do {					      \
-		if (!((uintptr_t)(i) & 0xffffffff00000000ULL))		      \
+		if ((long)(i) >= -2147483648 &&				      \
+				(long)(i) < 2147483648)			      \
 			PPC_LI32(d, i);					      \
 		else {							      \
-			PPC_LIS(d, ((uintptr_t)(i) >> 48));		      \
-			if ((uintptr_t)(i) & 0x0000ffff00000000ULL)	      \
-				PPC_ORI(d, d,				      \
-					((uintptr_t)(i) >> 32) & 0xffff);     \
+			if (!((uintptr_t)(i) & 0xffff800000000000ULL))	      \
+				PPC_LI(d, ((uintptr_t)(i) >> 32) & 0xffff);   \
+			else {						      \
+				PPC_LIS(d, ((uintptr_t)(i) >> 48));	      \
+				if ((uintptr_t)(i) & 0x0000ffff00000000ULL)   \
+					PPC_ORI(d, d,			      \
+					  ((uintptr_t)(i) >> 32) & 0xffff);   \
+			}						      \
 			PPC_SLDI(d, d, 32);				      \
 			if ((uintptr_t)(i) & 0x00000000ffff0000ULL)	      \
 				PPC_ORIS(d, d,				      \
 					 ((uintptr_t)(i) >> 16) & 0xffff);    \
 			if ((uintptr_t)(i) & 0x000000000000ffffULL)	      \
 				PPC_ORI(d, d, (uintptr_t)(i) & 0xffff);	      \
-		} } while (0);
+		} } while (0)
 
 #ifdef CONFIG_PPC64
 #define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
-- 
2.7.4

[RFC PATCH 3/6] ppc: bpf/jit: Introduce rotate immediate instructions

[Naveen N. Rao]

Since we will be using the rotate immediate instructions for extended
BPF JIT, let's introduce macros for the same. And since the shift
immediate operations use the rotate immediate instructions, let's redo
those macros to use the newly introduced instructions.

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/ppc-opcode.h |  2 ++
 arch/powerpc/net/bpf_jit.h            | 20 +++++++++++---------
 2 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 7ab04fc..95fd811 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -271,6 +271,8 @@
 #define __PPC_SH(s)	__PPC_WS(s)
 #define __PPC_MB(s)	(((s) & 0x1f) << 6)
 #define __PPC_ME(s)	(((s) & 0x1f) << 1)
+#define __PPC_MB64(s)	(__PPC_MB(s) | ((s) & 0x20))
+#define __PPC_ME64(s)	__PPC_MB64(s)
 #define __PPC_BI(s)	(((s) & 0x1f) << 16)
 #define __PPC_CT(t)	(((t) & 0x0f) << 21)
 
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 4c1e055..95d0e38 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -210,18 +210,20 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 				     ___PPC_RS(a) | ___PPC_RB(s))
 #define PPC_SRW(d, a, s)	EMIT(PPC_INST_SRW | ___PPC_RA(d) |	      \
 				     ___PPC_RS(a) | ___PPC_RB(s))
+#define PPC_RLWINM(d, a, i, mb, me)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
+					___PPC_RS(a) | __PPC_SH(i) |	      \
+					__PPC_MB(mb) | __PPC_ME(me))
+#define PPC_RLDICR(d, a, i, me)		EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
+					___PPC_RS(a) | __PPC_SH(i) |	      \
+					__PPC_ME64(me) | (((i) & 0x20) >> 4))
+
 /* slwi = rlwinm Rx, Ry, n, 0, 31-n */
-#define PPC_SLWI(d, a, i)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) |	      \
-				     ___PPC_RS(a) | __PPC_SH(i) |	      \
-				     __PPC_MB(0) | __PPC_ME(31-(i)))
+#define PPC_SLWI(d, a, i)	PPC_RLWINM(d, a, i, 0, 31-(i))
 /* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
-#define PPC_SRWI(d, a, i)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) |	      \
-				     ___PPC_RS(a) | __PPC_SH(32-(i)) |	      \
-				     __PPC_MB(i) | __PPC_ME(31))
+#define PPC_SRWI(d, a, i)	PPC_RLWINM(d, a, 32-(i), i, 31)
 /* sldi = rldicr Rx, Ry, n, 63-n */
-#define PPC_SLDI(d, a, i)	EMIT(PPC_INST_RLDICR | ___PPC_RA(d) |	      \
-				     ___PPC_RS(a) | __PPC_SH(i) |	      \
-				     __PPC_MB(63-(i)) | (((i) & 0x20) >> 4))
+#define PPC_SLDI(d, a, i)	PPC_RLDICR(d, a, i, 63-(i))
+
 #define PPC_NEG(d, a)		EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))
 
 /* Long jump; (unconditional 'branch') */
-- 
2.7.4

[RFC PATCH 4/6] ppc: bpf/jit: A few cleanups

[Naveen N. Rao]

1. Per the ISA, ADDIS actually uses RT, rather than RS. Though
the result is the same, make the usage clear.
2. The multiply instruction used is a 32-bit multiply. Rename PPC_MUL()
to PPC_MULW() to make the same clear.
3. PPC_STW[U] take the entire 16-bit immediate value and do not require
word-alignment, per the ISA. Change the macros to use IMM_L().
4. A few white-space cleanups to satisfy checkpatch.pl.

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/net/bpf_jit.h      | 13 +++++++------
 arch/powerpc/net/bpf_jit_comp.c |  8 ++++----
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 95d0e38..9041d3f 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -83,7 +83,7 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
  */
 #define IMM_H(i)		((uintptr_t)(i)>>16)
 #define IMM_HA(i)		(((uintptr_t)(i)>>16) +			      \
-				 (((uintptr_t)(i) & 0x8000) >> 15))
+					(((uintptr_t)(i) & 0x8000) >> 15))
 #define IMM_L(i)		((uintptr_t)(i) & 0xffff)
 
 #define PLANT_INSTR(d, idx, instr)					      \
@@ -99,16 +99,16 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 #define PPC_MR(d, a)		PPC_OR(d, a, a)
 #define PPC_LI(r, i)		PPC_ADDI(r, 0, i)
 #define PPC_ADDIS(d, a, i)	EMIT(PPC_INST_ADDIS |			      \
-				     ___PPC_RS(d) | ___PPC_RA(a) | IMM_L(i))
+				     ___PPC_RT(d) | ___PPC_RA(a) | IMM_L(i))
 #define PPC_LIS(r, i)		PPC_ADDIS(r, 0, i)
 #define PPC_STD(r, base, i)	EMIT(PPC_INST_STD | ___PPC_RS(r) |	      \
 				     ___PPC_RA(base) | ((i) & 0xfffc))
 #define PPC_STDU(r, base, i)	EMIT(PPC_INST_STDU | ___PPC_RS(r) |	      \
 				     ___PPC_RA(base) | ((i) & 0xfffc))
 #define PPC_STW(r, base, i)	EMIT(PPC_INST_STW | ___PPC_RS(r) |	      \
-				     ___PPC_RA(base) | ((i) & 0xfffc))
+				     ___PPC_RA(base) | IMM_L(i))
 #define PPC_STWU(r, base, i)	EMIT(PPC_INST_STWU | ___PPC_RS(r) |	      \
-				     ___PPC_RA(base) | ((i) & 0xfffc))
+				     ___PPC_RA(base) | IMM_L(i))
 
 #define PPC_LBZ(r, base, i)	EMIT(PPC_INST_LBZ | ___PPC_RT(r) |	      \
 				     ___PPC_RA(base) | IMM_L(i))
@@ -174,13 +174,14 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 #define PPC_CMPWI(a, i)		EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPDI(a, i)		EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPLWI(a, i)	EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
-#define PPC_CMPLW(a, b)		EMIT(PPC_INST_CMPLW | ___PPC_RA(a) | ___PPC_RB(b))
+#define PPC_CMPLW(a, b)		EMIT(PPC_INST_CMPLW | ___PPC_RA(a) |	      \
+					___PPC_RB(b))
 
 #define PPC_SUB(d, a, b)	EMIT(PPC_INST_SUB | ___PPC_RT(d) |	      \
 				     ___PPC_RB(a) | ___PPC_RA(b))
 #define PPC_ADD(d, a, b)	EMIT(PPC_INST_ADD | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
-#define PPC_MUL(d, a, b)	EMIT(PPC_INST_MULLW | ___PPC_RT(d) |	      \
+#define PPC_MULW(d, a, b)	EMIT(PPC_INST_MULLW | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
 #define PPC_MULHWU(d, a, b)	EMIT(PPC_INST_MULHWU | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 2d66a84..6012aac 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -161,14 +161,14 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 			break;
 		case BPF_ALU | BPF_MUL | BPF_X: /* A *= X; */
 			ctx->seen |= SEEN_XREG;
-			PPC_MUL(r_A, r_A, r_X);
+			PPC_MULW(r_A, r_A, r_X);
 			break;
 		case BPF_ALU | BPF_MUL | BPF_K: /* A *= K */
 			if (K < 32768)
 				PPC_MULI(r_A, r_A, K);
 			else {
 				PPC_LI32(r_scratch1, K);
-				PPC_MUL(r_A, r_A, r_scratch1);
+				PPC_MULW(r_A, r_A, r_scratch1);
 			}
 			break;
 		case BPF_ALU | BPF_MOD | BPF_X: /* A %= X; */
@@ -184,7 +184,7 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 			}
 			if (code == (BPF_ALU | BPF_MOD | BPF_X)) {
 				PPC_DIVWU(r_scratch1, r_A, r_X);
-				PPC_MUL(r_scratch1, r_X, r_scratch1);
+				PPC_MULW(r_scratch1, r_X, r_scratch1);
 				PPC_SUB(r_A, r_A, r_scratch1);
 			} else {
 				PPC_DIVWU(r_A, r_A, r_X);
@@ -193,7 +193,7 @@ static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
 		case BPF_ALU | BPF_MOD | BPF_K: /* A %= K; */
 			PPC_LI32(r_scratch2, K);
 			PPC_DIVWU(r_scratch1, r_A, r_scratch2);
-			PPC_MUL(r_scratch1, r_scratch2, r_scratch1);
+			PPC_MULW(r_scratch1, r_scratch2, r_scratch1);
 			PPC_SUB(r_A, r_A, r_scratch1);
 			break;
 		case BPF_ALU | BPF_DIV | BPF_K: /* A /= K */
-- 
2.7.4

[RFC PATCH 5/6] ppc: bpf/jit: Isolate classic BPF JIT specifics into a separate header

[Naveen N. Rao]

Break out classic BPF JIT specifics into a separate header in
preparation for eBPF JIT implementation. Note that ppc32 will still need
the classic BPF JIT.

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/net/bpf_jit.h      | 122 +---------------------------------
 arch/powerpc/net/bpf_jit32.h    | 140 ++++++++++++++++++++++++++++++++++++++++
 arch/powerpc/net/bpf_jit_asm.S  |   2 +-
 arch/powerpc/net/bpf_jit_comp.c |   2 +-
 4 files changed, 145 insertions(+), 121 deletions(-)
 create mode 100644 arch/powerpc/net/bpf_jit32.h

diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index 9041d3f..f650767 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -1,6 +1,8 @@
-/* bpf_jit.h: BPF JIT compiler for PPC64
+/*
+ * 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>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -10,66 +12,8 @@
 #ifndef _BPF_JIT_H
 #define _BPF_JIT_H
 
-#ifdef CONFIG_PPC64
-#define BPF_PPC_STACK_R3_OFF	48
-#define BPF_PPC_STACK_LOCALS	32
-#define BPF_PPC_STACK_BASIC	(48+64)
-#define BPF_PPC_STACK_SAVE	(18*8)
-#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
-				 BPF_PPC_STACK_SAVE)
-#define BPF_PPC_SLOWPATH_FRAME	(48+64)
-#else
-#define BPF_PPC_STACK_R3_OFF	24
-#define BPF_PPC_STACK_LOCALS	16
-#define BPF_PPC_STACK_BASIC	(24+32)
-#define BPF_PPC_STACK_SAVE	(18*4)
-#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
-				 BPF_PPC_STACK_SAVE)
-#define BPF_PPC_SLOWPATH_FRAME	(24+32)
-#endif
-
-#define REG_SZ         (BITS_PER_LONG/8)
-
-/*
- * Generated code register usage:
- *
- * As normal PPC C ABI (e.g. r1=sp, r2=TOC), with:
- *
- * skb		r3	(Entry parameter)
- * A register	r4
- * X register	r5
- * addr param	r6
- * r7-r10	scratch
- * skb->data	r14
- * skb headlen	r15	(skb->len - skb->data_len)
- * m[0]		r16
- * m[...]	...
- * m[15]	r31
- */
-#define r_skb		3
-#define r_ret		3
-#define r_A		4
-#define r_X		5
-#define r_addr		6
-#define r_scratch1	7
-#define r_scratch2	8
-#define r_D		14
-#define r_HL		15
-#define r_M		16
-
 #ifndef __ASSEMBLY__
 
-/*
- * Assembly helpers from arch/powerpc/net/bpf_jit.S:
- */
-#define DECLARE_LOAD_FUNC(func)	\
-	extern u8 func[], func##_negative_offset[], func##_positive_offset[]
-
-DECLARE_LOAD_FUNC(sk_load_word);
-DECLARE_LOAD_FUNC(sk_load_half);
-DECLARE_LOAD_FUNC(sk_load_byte);
-DECLARE_LOAD_FUNC(sk_load_byte_msh);
-
 #ifdef CONFIG_PPC64
 #define FUNCTION_DESCR_SIZE	24
 #else
@@ -131,46 +75,6 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 #define PPC_BPF_STLU(r, base, i) do { PPC_STWU(r, base, i); } while(0)
 #endif
 
-/* Convenience helpers for the above with 'far' offsets: */
-#define PPC_LBZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LBZ(r, base, i);   \
-		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
-			PPC_LBZ(r, r, IMM_L(i)); } } while(0)
-
-#define PPC_LD_OFFS(r, base, i) do { if ((i) < 32768) PPC_LD(r, base, i);     \
-		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
-			PPC_LD(r, r, IMM_L(i)); } } while(0)
-
-#define PPC_LWZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LWZ(r, base, i);   \
-		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
-			PPC_LWZ(r, r, IMM_L(i)); } } while(0)
-
-#define PPC_LHZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LHZ(r, base, i);   \
-		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
-			PPC_LHZ(r, r, IMM_L(i)); } } while(0)
-
-#ifdef CONFIG_PPC64
-#define PPC_LL_OFFS(r, base, i) do { PPC_LD_OFFS(r, base, i); } while(0)
-#else
-#define PPC_LL_OFFS(r, base, i) do { PPC_LWZ_OFFS(r, base, i); } while(0)
-#endif
-
-#ifdef CONFIG_SMP
-#ifdef CONFIG_PPC64
-#define PPC_BPF_LOAD_CPU(r)		\
-	do { BUILD_BUG_ON(FIELD_SIZEOF(struct paca_struct, paca_index) != 2);	\
-		PPC_LHZ_OFFS(r, 13, offsetof(struct paca_struct, paca_index));		\
-	} while (0)
-#else
-#define PPC_BPF_LOAD_CPU(r)     \
-	do { BUILD_BUG_ON(FIELD_SIZEOF(struct thread_info, cpu) != 4);			\
-		PPC_LHZ_OFFS(r, (1 & ~(THREAD_SIZE - 1)),							\
-				offsetof(struct thread_info, cpu));							\
-	} while(0)
-#endif
-#else
-#define PPC_BPF_LOAD_CPU(r) do { PPC_LI(r, 0); } while(0)
-#endif
-
 #define PPC_CMPWI(a, i)		EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPDI(a, i)		EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPLWI(a, i)	EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
@@ -273,14 +177,6 @@ DECLARE_LOAD_FUNC(sk_load_byte_msh);
 #define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
 #endif
 
-#define PPC_LHBRX_OFFS(r, base, i) \
-		do { PPC_LI32(r, i); PPC_LHBRX(r, r, base); } while(0)
-#ifdef __LITTLE_ENDIAN__
-#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHBRX_OFFS(r, base, i)
-#else
-#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHZ_OFFS(r, base, i)
-#endif
-
 static inline bool is_nearbranch(int offset)
 {
 	return (offset < 32768) && (offset >= -32768);
@@ -317,18 +213,6 @@ static inline bool is_nearbranch(int offset)
 #define COND_NE		(CR0_EQ | COND_CMP_FALSE)
 #define COND_LT		(CR0_LT | COND_CMP_TRUE)
 
-#define SEEN_DATAREF 0x10000 /* might call external helpers */
-#define SEEN_XREG    0x20000 /* X reg is used */
-#define SEEN_MEM     0x40000 /* SEEN_MEM+(1<<n) = use mem[n] for temporary
-			      * storage */
-#define SEEN_MEM_MSK 0x0ffff
-
-struct codegen_context {
-	unsigned int seen;
-	unsigned int idx;
-	int pc_ret0; /* bpf index of first RET #0 instruction (if any) */
-};
-
 #endif
 
 #endif
diff --git a/arch/powerpc/net/bpf_jit32.h b/arch/powerpc/net/bpf_jit32.h
new file mode 100644
index 0000000..d1b8728
--- /dev/null
+++ b/arch/powerpc/net/bpf_jit32.h
@@ -0,0 +1,140 @@
+/*
+ * bpf_jit32.h: BPF JIT compiler for PPC64
+ *
+ * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
+ *	     2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
+ *
+ * Split from bpf_jit.h
+ *
+ * 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_JIT32_H
+#define _BPF_JIT32_H
+
+#include "bpf_jit.h"
+
+#ifdef CONFIG_PPC64
+#define BPF_PPC_STACK_R3_OFF	48
+#define BPF_PPC_STACK_LOCALS	32
+#define BPF_PPC_STACK_BASIC	(48+64)
+#define BPF_PPC_STACK_SAVE	(18*8)
+#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
+				 BPF_PPC_STACK_SAVE)
+#define BPF_PPC_SLOWPATH_FRAME	(48+64)
+#else
+#define BPF_PPC_STACK_R3_OFF	24
+#define BPF_PPC_STACK_LOCALS	16
+#define BPF_PPC_STACK_BASIC	(24+32)
+#define BPF_PPC_STACK_SAVE	(18*4)
+#define BPF_PPC_STACKFRAME	(BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
+				 BPF_PPC_STACK_SAVE)
+#define BPF_PPC_SLOWPATH_FRAME	(24+32)
+#endif
+
+#define REG_SZ         (BITS_PER_LONG/8)
+
+/*
+ * Generated code register usage:
+ *
+ * As normal PPC C ABI (e.g. r1=sp, r2=TOC), with:
+ *
+ * skb		r3	(Entry parameter)
+ * A register	r4
+ * X register	r5
+ * addr param	r6
+ * r7-r10	scratch
+ * skb->data	r14
+ * skb headlen	r15	(skb->len - skb->data_len)
+ * m[0]		r16
+ * m[...]	...
+ * m[15]	r31
+ */
+#define r_skb		3
+#define r_ret		3
+#define r_A		4
+#define r_X		5
+#define r_addr		6
+#define r_scratch1	7
+#define r_scratch2	8
+#define r_D		14
+#define r_HL		15
+#define r_M		16
+
+#ifndef __ASSEMBLY__
+
+/*
+ * Assembly helpers from arch/powerpc/net/bpf_jit.S:
+ */
+#define DECLARE_LOAD_FUNC(func)	\
+	extern u8 func[], func##_negative_offset[], func##_positive_offset[]
+
+DECLARE_LOAD_FUNC(sk_load_word);
+DECLARE_LOAD_FUNC(sk_load_half);
+DECLARE_LOAD_FUNC(sk_load_byte);
+DECLARE_LOAD_FUNC(sk_load_byte_msh);
+
+#define PPC_LBZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LBZ(r, base, i);   \
+		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
+			PPC_LBZ(r, r, IMM_L(i)); } } while(0)
+
+#define PPC_LD_OFFS(r, base, i) do { if ((i) < 32768) PPC_LD(r, base, i);     \
+		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
+			PPC_LD(r, r, IMM_L(i)); } } while(0)
+
+#define PPC_LWZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LWZ(r, base, i);   \
+		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
+			PPC_LWZ(r, r, IMM_L(i)); } } while(0)
+
+#define PPC_LHZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LHZ(r, base, i);   \
+		else {	PPC_ADDIS(r, base, IMM_HA(i));			      \
+			PPC_LHZ(r, r, IMM_L(i)); } } while(0)
+
+#ifdef CONFIG_PPC64
+#define PPC_LL_OFFS(r, base, i) do { PPC_LD_OFFS(r, base, i); } while(0)
+#else
+#define PPC_LL_OFFS(r, base, i) do { PPC_LWZ_OFFS(r, base, i); } while(0)
+#endif
+
+#ifdef CONFIG_SMP
+#ifdef CONFIG_PPC64
+#define PPC_BPF_LOAD_CPU(r)		\
+	do { BUILD_BUG_ON(FIELD_SIZEOF(struct paca_struct, paca_index) != 2);	\
+		PPC_LHZ_OFFS(r, 13, offsetof(struct paca_struct, paca_index));	\
+	} while (0)
+#else
+#define PPC_BPF_LOAD_CPU(r)     \
+	do { BUILD_BUG_ON(FIELD_SIZEOF(struct thread_info, cpu) != 4);		\
+		PPC_LHZ_OFFS(r, (1 & ~(THREAD_SIZE - 1)),			\
+				offsetof(struct thread_info, cpu));		\
+	} while(0)
+#endif
+#else
+#define PPC_BPF_LOAD_CPU(r) do { PPC_LI(r, 0); } while(0)
+#endif
+
+#define PPC_LHBRX_OFFS(r, base, i) \
+		do { PPC_LI32(r, i); PPC_LHBRX(r, r, base); } while(0)
+#ifdef __LITTLE_ENDIAN__
+#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHBRX_OFFS(r, base, i)
+#else
+#define PPC_NTOHS_OFFS(r, base, i)	PPC_LHZ_OFFS(r, base, i)
+#endif
+
+#define SEEN_DATAREF 0x10000 /* might call external helpers */
+#define SEEN_XREG    0x20000 /* X reg is used */
+#define SEEN_MEM     0x40000 /* SEEN_MEM+(1<<n) = use mem[n] for temporary
+			      * storage */
+#define SEEN_MEM_MSK 0x0ffff
+
+struct codegen_context {
+	unsigned int seen;
+	unsigned int idx;
+	int pc_ret0; /* bpf index of first RET #0 instruction (if any) */
+};
+
+#endif
+
+#endif
diff --git a/arch/powerpc/net/bpf_jit_asm.S b/arch/powerpc/net/bpf_jit_asm.S
index 8ff5a3b..3dd9c43 100644
--- a/arch/powerpc/net/bpf_jit_asm.S
+++ b/arch/powerpc/net/bpf_jit_asm.S
@@ -10,7 +10,7 @@
  */
 
 #include <asm/ppc_asm.h>
-#include "bpf_jit.h"
+#include "bpf_jit32.h"
 
 /*
  * All of these routines are called directly from generated code,
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 6012aac..7e706f3 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -16,7 +16,7 @@
 #include <linux/filter.h>
 #include <linux/if_vlan.h>
 
-#include "bpf_jit.h"
+#include "bpf_jit32.h"
 
 int bpf_jit_enable __read_mostly;
 
-- 
2.7.4

[RFC PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

[Naveen N. Rao]

PPC64 eBPF JIT compiler. Works for both ABIv1 and ABIv2.

Enable with:
echo 1 > /proc/sys/net/core/bpf_jit_enable
or
echo 2 > /proc/sys/net/core/bpf_jit_enable

... to see the generated JIT code. This can further be processed with
tools/net/bpf_jit_disasm.

With CONFIG_TEST_BPF=m and 'modprobe test_bpf':
test_bpf: Summary: 291 PASSED, 0 FAILED, [234/283 JIT'ed]

... on both ppc64 BE and LE.

The details of the approach are documented through various comments in
the code, as are the TODOs. Some of the prominent TODOs include
implementing BPF tail calls and skb loads.

Cc: Matt Evans <matt@ozlabs.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/include/asm/ppc-opcode.h |  19 +-
 arch/powerpc/net/Makefile             |   4 +
 arch/powerpc/net/bpf_jit.h            |  66 ++-
 arch/powerpc/net/bpf_jit64.h          |  58 +++
 arch/powerpc/net/bpf_jit_comp64.c     | 828 ++++++++++++++++++++++++++++++++++
 5 files changed, 973 insertions(+), 2 deletions(-)
 create mode 100644 arch/powerpc/net/bpf_jit64.h
 create mode 100644 arch/powerpc/net/bpf_jit_comp64.c

diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
index 95fd811..bca92e8 100644
--- a/arch/powerpc/include/asm/ppc-opcode.h
+++ b/arch/powerpc/include/asm/ppc-opcode.h
@@ -141,9 +141,11 @@
 #define PPC_INST_ISEL			0x7c00001e
 #define PPC_INST_ISEL_MASK		0xfc00003e
 #define PPC_INST_LDARX			0x7c0000a8
+#define PPC_INST_STDCX			0x7c0001ad
 #define PPC_INST_LSWI			0x7c0004aa
 #define PPC_INST_LSWX			0x7c00042a
 #define PPC_INST_LWARX			0x7c000028
+#define PPC_INST_STWCX			0x7c00012d
 #define PPC_INST_LWSYNC			0x7c2004ac
 #define PPC_INST_SYNC			0x7c0004ac
 #define PPC_INST_SYNC_MASK		0xfc0007fe
@@ -210,8 +212,11 @@
 #define PPC_INST_LBZ			0x88000000
 #define PPC_INST_LD			0xe8000000
 #define PPC_INST_LHZ			0xa0000000
-#define PPC_INST_LHBRX			0x7c00062c
 #define PPC_INST_LWZ			0x80000000
+#define PPC_INST_LHBRX			0x7c00062c
+#define PPC_INST_LDBRX			0x7c000428
+#define PPC_INST_STB			0x98000000
+#define PPC_INST_STH			0xb0000000
 #define PPC_INST_STD			0xf8000000
 #define PPC_INST_STDU			0xf8000001
 #define PPC_INST_STW			0x90000000
@@ -220,22 +225,34 @@
 #define PPC_INST_MTLR			0x7c0803a6
 #define PPC_INST_CMPWI			0x2c000000
 #define PPC_INST_CMPDI			0x2c200000
+#define PPC_INST_CMPW			0x7c000000
+#define PPC_INST_CMPD			0x7c200000
 #define PPC_INST_CMPLW			0x7c000040
+#define PPC_INST_CMPLD			0x7c200040
 #define PPC_INST_CMPLWI			0x28000000
+#define PPC_INST_CMPLDI			0x28200000
 #define PPC_INST_ADDI			0x38000000
 #define PPC_INST_ADDIS			0x3c000000
 #define PPC_INST_ADD			0x7c000214
 #define PPC_INST_SUB			0x7c000050
 #define PPC_INST_BLR			0x4e800020
 #define PPC_INST_BLRL			0x4e800021
+#define PPC_INST_MULLD			0x7c0001d2
 #define PPC_INST_MULLW			0x7c0001d6
 #define PPC_INST_MULHWU			0x7c000016
 #define PPC_INST_MULLI			0x1c000000
 #define PPC_INST_DIVWU			0x7c000396
+#define PPC_INST_DIVD			0x7c0003d2
 #define PPC_INST_RLWINM			0x54000000
+#define PPC_INST_RLWIMI			0x50000000
+#define PPC_INST_RLDICL			0x78000000
 #define PPC_INST_RLDICR			0x78000004
 #define PPC_INST_SLW			0x7c000030
+#define PPC_INST_SLD			0x7c000036
 #define PPC_INST_SRW			0x7c000430
+#define PPC_INST_SRD			0x7c000436
+#define PPC_INST_SRAD			0x7c000634
+#define PPC_INST_SRADI			0x7c000674
 #define PPC_INST_AND			0x7c000038
 #define PPC_INST_ANDDOT			0x7c000039
 #define PPC_INST_OR			0x7c000378
diff --git a/arch/powerpc/net/Makefile b/arch/powerpc/net/Makefile
index 1306a58..968c1fc3 100644
--- a/arch/powerpc/net/Makefile
+++ b/arch/powerpc/net/Makefile
@@ -1,4 +1,8 @@
 #
 # Arch-specific network modules
 #
+ifeq ($(CONFIG_PPC64),y)
+obj-$(CONFIG_BPF_JIT) += bpf_jit_comp64.o
+else
 obj-$(CONFIG_BPF_JIT) += bpf_jit_asm.o bpf_jit_comp.o
+endif
diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
index f650767..92c63a1 100644
--- a/arch/powerpc/net/bpf_jit.h
+++ b/arch/powerpc/net/bpf_jit.h
@@ -14,7 +14,7 @@
 
 #ifndef __ASSEMBLY__
 
-#ifdef CONFIG_PPC64
+#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)
 #define FUNCTION_DESCR_SIZE	24
 #else
 #define FUNCTION_DESCR_SIZE	0
@@ -53,6 +53,10 @@
 				     ___PPC_RA(base) | IMM_L(i))
 #define PPC_STWU(r, base, i)	EMIT(PPC_INST_STWU | ___PPC_RS(r) |	      \
 				     ___PPC_RA(base) | IMM_L(i))
+#define PPC_STH(r, base, i)	EMIT(PPC_INST_STH | ___PPC_RS(r) |	      \
+				     ___PPC_RA(base) | IMM_L(i))
+#define PPC_STB(r, base, i)	EMIT(PPC_INST_STB | ___PPC_RS(r) |	      \
+				     ___PPC_RA(base) | IMM_L(i))
 
 #define PPC_LBZ(r, base, i)	EMIT(PPC_INST_LBZ | ___PPC_RT(r) |	      \
 				     ___PPC_RA(base) | IMM_L(i))
@@ -64,6 +68,31 @@
 				     ___PPC_RA(base) | IMM_L(i))
 #define PPC_LHBRX(r, base, b)	EMIT(PPC_INST_LHBRX | ___PPC_RT(r) |	      \
 				     ___PPC_RA(base) | ___PPC_RB(b))
+#define PPC_LDBRX(r, base, b)	EMIT(PPC_INST_LDBRX | ___PPC_RT(r) |	      \
+				     ___PPC_RA(base) | ___PPC_RB(b))
+
+/*
+ * TODO: Ugly hack for now, as these are defined in ppc-opcode.h
+ * There are two ways to address this:
+ * 1. move all these generic instruction macros PPC_* to ppc-opcode.h and change
+ *    bpf_jit_comp.c to simply use EMIT(PPC_*)
+ * 2. rename all PPC_* macros here to PPC_BPF_* macros and change bpf_jit_comp.c
+ *    to use the new names.
+ * The former may be preferable if these generic macros will be useful elsewhere
+ * in the kernel.
+ */
+#undef PPC_LDARX
+#define PPC_LDARX(t, a, b, eh)	EMIT(PPC_INST_LDARX | ___PPC_RT(t) |	      \
+					___PPC_RA(a) | ___PPC_RB(b) |	      \
+					__PPC_EH(eh))
+#undef PPC_LWARX
+#define PPC_LWARX(t, a, b, eh)	EMIT(PPC_INST_LWARX | ___PPC_RT(t) |	      \
+					___PPC_RA(a) | ___PPC_RB(b) |	      \
+					__PPC_EH(eh))
+#define PPC_STWCX(s, a, b)	EMIT(PPC_INST_STWCX | ___PPC_RS(s) |	      \
+					___PPC_RA(a) | ___PPC_RB(b))
+#define PPC_STDCX(s, a, b)	EMIT(PPC_INST_STDCX | ___PPC_RS(s) |	      \
+					___PPC_RA(a) | ___PPC_RB(b))
 
 #ifdef CONFIG_PPC64
 #define PPC_BPF_LL(r, base, i) do { PPC_LD(r, base, i); } while(0)
@@ -77,14 +106,23 @@
 
 #define PPC_CMPWI(a, i)		EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPDI(a, i)		EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
+#define PPC_CMPW(a, b)		EMIT(PPC_INST_CMPW | ___PPC_RA(a) |	      \
+					___PPC_RB(b))
+#define PPC_CMPD(a, b)		EMIT(PPC_INST_CMPD | ___PPC_RA(a) |	      \
+					___PPC_RB(b))
 #define PPC_CMPLWI(a, i)	EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
+#define PPC_CMPLDI(a, i)	EMIT(PPC_INST_CMPLDI | ___PPC_RA(a) | IMM_L(i))
 #define PPC_CMPLW(a, b)		EMIT(PPC_INST_CMPLW | ___PPC_RA(a) |	      \
 					___PPC_RB(b))
+#define PPC_CMPLD(a, b)		EMIT(PPC_INST_CMPLD | ___PPC_RA(a) |	      \
+					___PPC_RB(b))
 
 #define PPC_SUB(d, a, b)	EMIT(PPC_INST_SUB | ___PPC_RT(d) |	      \
 				     ___PPC_RB(a) | ___PPC_RA(b))
 #define PPC_ADD(d, a, b)	EMIT(PPC_INST_ADD | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
+#define PPC_MULD(d, a, b)	EMIT(PPC_INST_MULLD | ___PPC_RT(d) |	      \
+				     ___PPC_RA(a) | ___PPC_RB(b))
 #define PPC_MULW(d, a, b)	EMIT(PPC_INST_MULLW | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
 #define PPC_MULHWU(d, a, b)	EMIT(PPC_INST_MULHWU | ___PPC_RT(d) |	      \
@@ -93,6 +131,8 @@
 				     ___PPC_RA(a) | IMM_L(i))
 #define PPC_DIVWU(d, a, b)	EMIT(PPC_INST_DIVWU | ___PPC_RT(d) |	      \
 				     ___PPC_RA(a) | ___PPC_RB(b))
+#define PPC_DIVD(d, a, b)	EMIT(PPC_INST_DIVD | ___PPC_RT(d) |	      \
+				     ___PPC_RA(a) | ___PPC_RB(b))
 #define PPC_AND(d, a, b)	EMIT(PPC_INST_AND | ___PPC_RA(d) |	      \
 				     ___PPC_RS(a) | ___PPC_RB(b))
 #define PPC_ANDI(d, a, i)	EMIT(PPC_INST_ANDI | ___PPC_RA(d) |	      \
@@ -113,11 +153,26 @@
 				     ___PPC_RS(a) | IMM_L(i))
 #define PPC_SLW(d, a, s)	EMIT(PPC_INST_SLW | ___PPC_RA(d) |	      \
 				     ___PPC_RS(a) | ___PPC_RB(s))
+#define PPC_SLD(d, a, s)	EMIT(PPC_INST_SLD | ___PPC_RA(d) |	      \
+				     ___PPC_RS(a) | ___PPC_RB(s))
 #define PPC_SRW(d, a, s)	EMIT(PPC_INST_SRW | ___PPC_RA(d) |	      \
 				     ___PPC_RS(a) | ___PPC_RB(s))
+#define PPC_SRD(d, a, s)	EMIT(PPC_INST_SRD | ___PPC_RA(d) |	      \
+				     ___PPC_RS(a) | ___PPC_RB(s))
+#define PPC_SRAD(d, a, s)	EMIT(PPC_INST_SRAD | ___PPC_RA(d) |	      \
+				     ___PPC_RS(a) | ___PPC_RB(s))
+#define PPC_SRADI(d, a, i)	EMIT(PPC_INST_SRADI | ___PPC_RA(d) |	      \
+				     ___PPC_RS(a) | __PPC_SH(i) |             \
+				     (((i) & 0x20) >> 4))
 #define PPC_RLWINM(d, a, i, mb, me)	EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
 					___PPC_RS(a) | __PPC_SH(i) |	      \
 					__PPC_MB(mb) | __PPC_ME(me))
+#define PPC_RLWIMI(d, a, i, mb, me)	EMIT(PPC_INST_RLWIMI | ___PPC_RA(d) | \
+					___PPC_RS(a) | __PPC_SH(i) |	      \
+					__PPC_MB(mb) | __PPC_ME(me))
+#define PPC_RLDICL(d, a, i, mb)		EMIT(PPC_INST_RLDICL | ___PPC_RA(d) | \
+					___PPC_RS(a) | __PPC_SH(i) |	      \
+					__PPC_MB64(mb) | (((i) & 0x20) >> 4))
 #define PPC_RLDICR(d, a, i, me)		EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
 					___PPC_RS(a) | __PPC_SH(i) |	      \
 					__PPC_ME64(me) | (((i) & 0x20) >> 4))
@@ -128,6 +183,8 @@
 #define PPC_SRWI(d, a, i)	PPC_RLWINM(d, a, 32-(i), i, 31)
 /* sldi = rldicr Rx, Ry, n, 63-n */
 #define PPC_SLDI(d, a, i)	PPC_RLDICR(d, a, i, 63-(i))
+/* sldi = rldicl Rx, Ry, 64-n, n */
+#define PPC_SRDI(d, a, i)	PPC_RLDICL(d, a, 64-(i), i)
 
 #define PPC_NEG(d, a)		EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))
 
@@ -150,6 +207,13 @@
 				PPC_ORI(d, d, IMM_L(i));		      \
 		} } while(0)
 
+/* Unsigned 32-bit immediate load */
+#define PPC_LI32U(d, i)		do {					      \
+		PPC_LI32(d, i);						      \
+		if ((int)(uintptr_t)(i) < 0)				      \
+			PPC_RLWINM(d, d, 0, 0, 31);			      \
+		} while (0)
+
 #define PPC_LI64(d, i)		do {					      \
 		if ((long)(i) >= -2147483648 &&				      \
 				(long)(i) < 2147483648)			      \
diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h
new file mode 100644
index 0000000..bb9cbb4
--- /dev/null
+++ b/arch/powerpc/net/bpf_jit64.h
@@ -0,0 +1,58 @@
+/*
+ * 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:
+ *
+ *		[	prev sp		] <-------------
+ *		[   nv gpr save area	] 6*8		|
+ * fp (r31) -->	[   ebpf stack space	] 512		|
+ *		[  local/tmp var space	] 16		|
+ *		[     frame header	] 32/112	|
+ * sp (r1) --->	[    stack pointer	] --------------
+ */
+
+/* for bpf JIT code internal usage */
+#define BPF_PPC_STACK_LOCALS	16
+/* for gpr non volatile registers BPG_REG_6 to 10 */
+#define BPF_PPC_STACK_SAVE	(6*8)
+/* Ensure this is quadword aligned */
+#define BPF_PPC_STACKFRAME	(STACK_FRAME_MIN_SIZE + BPF_PPC_STACK_LOCALS + \
+				 MAX_BPF_STACK + BPF_PPC_STACK_SAVE)
+
+/* Truncate to 32-bit */
+#define PPC_CLEAR32()	   do {						      \
+			   if (BPF_CLASS(code) == BPF_ALU)		      \
+				PPC_RLWINM(dst_reg, dst_reg, 0, 0, 31);	      \
+			   } while (0)
+
+#define SEEN_FUNC	0x1000 /* might call external helpers */
+#define SEEN_STACK	0x2000 /* uses BPF stack */
+
+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 r26-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;
+};
+
+#endif
diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c
new file mode 100644
index 0000000..deb15fc
--- /dev/null
+++ b/arch/powerpc/net/bpf_jit_comp64.c
@@ -0,0 +1,828 @@
+/*
+ * 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 compiler by Matt Evans
+ *
+ * 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/moduleloader.h>
+#include <asm/cacheflush.h>
+#include <linux/netdevice.h>
+#include <linux/filter.h>
+#include <linux/if_vlan.h>
+
+#include "bpf_jit64.h"
+
+int bpf_jit_enable __read_mostly;
+
+#define TMP_REG_1 (MAX_BPF_REG + 0)
+#define TMP_REG_2 (MAX_BPF_REG + 1)
+
+/* BPF to ppc register mappings */
+static const int b2p[] = {
+	/* function return value */
+	[BPF_REG_0] = 10,
+	/* 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] = 30,
+	[BPF_REG_7] = 29,
+	[BPF_REG_8] = 28,
+	[BPF_REG_9] = 26,
+	/* frame pointer aka BPF_REG_10 */
+	[BPF_REG_FP] = 31,
+	/* eBPF jit internal registers */
+	[TMP_REG_1] = 8,
+	[TMP_REG_2] = 9,
+};
+
+static inline bool bpf_is_seen_register(struct codegen_context *ctx, int i)
+{
+	return (ctx->seen & (1 << (31 - b2p[i])));
+}
+
+static void bpf_jit_build_prologue(struct bpf_prog *fp, u32 *image,
+				   struct codegen_context *ctx)
+{
+	int i;
+	int new_stack_frame = 0;
+
+	/*
+	 * 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
+	 */
+	if (bpf_is_seen_register(ctx, BPF_REG_FP) || ctx->seen & SEEN_FUNC) {
+		new_stack_frame = 1;
+
+		/*
+		 * 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_INST_MFLR | __PPC_RT(R0));
+			PPC_BPF_STL(0, 1, PPC_LR_STKOFF);
+		}
+
+		PPC_BPF_STLU(1, 1, -BPF_PPC_STACKFRAME);
+	}
+
+	/*
+	 * 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, i))
+			PPC_BPF_STL(b2p[i], 1,
+				(new_stack_frame ? BPF_PPC_STACKFRAME : 0) -
+					(8 * (32 - b2p[i])));
+
+	/* Setup frame pointer to point to the bpf stack area */
+	if (bpf_is_seen_register(ctx, BPF_REG_FP))
+		PPC_ADDI(b2p[BPF_REG_FP], 1,
+				BPF_PPC_STACKFRAME - BPF_PPC_STACK_SAVE);
+}
+
+static void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx)
+{
+	int i;
+	int new_stack_frame = 0;
+
+	/* Move result to r3 */
+	PPC_ADDI(3, b2p[BPF_REG_0], 0);
+
+	/* Did we create our own stack frame? */
+	if (bpf_is_seen_register(ctx, BPF_REG_FP) || ctx->seen & SEEN_FUNC)
+		new_stack_frame = 1;
+
+	/* Restore NVRs */
+	for (i = BPF_REG_6; i <= BPF_REG_10; i++)
+		if (bpf_is_seen_register(ctx, i))
+			PPC_BPF_LL(b2p[i], 1,
+				(new_stack_frame ? BPF_PPC_STACKFRAME : 0) -
+					(8 * (32 - b2p[i])));
+
+	/* Tear down our stack frame */
+	if (new_stack_frame) {
+		PPC_ADDI(1, 1, BPF_PPC_STACKFRAME);
+		if (ctx->seen & SEEN_FUNC) {
+			PPC_BPF_LL(0, 1, PPC_LR_STKOFF);
+			PPC_MTLR(0);
+		}
+	}
+
+	PPC_BLR();
+}
+
+/* Assemble the body code between the prologue & epilogue */
+static int bpf_jit_build_body(struct bpf_prog *fp, u32 *image,
+			      struct codegen_context *ctx,
+			      u32 *addrs)
+{
+	const struct bpf_insn *insn = fp->insnsi;
+	int flen = fp->len;
+	int i;
+
+	/* 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 = b2p[insn[i].dst_reg];
+		u32 src_reg = b2p[insn[i].src_reg];
+		s16 off = insn[i].off;
+		s32 imm = insn[i].imm;
+		u64 imm64;
+		u8 *func;
+		u32 true_cond;
+		int stack_local_off;
+
+		/*
+		 * 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 >= 26 && dst_reg <= 31)
+			ctx->seen |= (1 << (31 - dst_reg));
+		if (src_reg >= 26 && src_reg <= 31)
+			ctx->seen |= (1 << (31 - 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 */
+			PPC_ADD(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_SUB | BPF_K: /* (u32) dst -= (u32) imm */
+		case BPF_ALU64 | BPF_SUB | BPF_K: /* dst -= imm */
+			imm = -imm;
+			/* fall through */
+		case BPF_ALU | BPF_ADD | BPF_K: /* (u32) dst += (u32) imm */
+		case BPF_ALU64 | BPF_ADD | BPF_K: /* dst += imm */
+			if (!imm)
+				break;
+			if (imm >= -32768 && imm < 32768)
+				PPC_ADDI(dst_reg, dst_reg, IMM_L(imm));
+			else {
+				PPC_LI32(b2p[TMP_REG_1], imm);
+				PPC_ADD(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			}
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_SUB | BPF_X: /* (u32) dst -= (u32) src */
+		case BPF_ALU64 | BPF_SUB | BPF_X: /* dst -= src */
+			PPC_SUB(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_MUL | BPF_X: /* (u32) dst *= (u32) src */
+			PPC_MULW(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU64 | BPF_MUL | BPF_X: /* dst *= src */
+			PPC_MULD(dst_reg, dst_reg, src_reg);
+			break;
+		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)
+				PPC_MULI(dst_reg, dst_reg, IMM_L(imm));
+			else {
+				PPC_LI32(b2p[TMP_REG_1], imm);
+				if (BPF_CLASS(code) == BPF_ALU)
+					PPC_MULW(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+				else
+					PPC_MULD(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+			}
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_DIV | BPF_X: /* (u32) dst /= (u32) src */
+		case BPF_ALU | BPF_MOD | BPF_X: /* (u32) dst %= (u32) src */
+			PPC_CMPWI(src_reg, 0);
+			PPC_BCC_SHORT(COND_NE, (ctx->idx * 4) + 12);
+			PPC_LI(b2p[BPF_REG_0], 0);
+			PPC_JMP(exit_addr);
+			if (BPF_OP(code) == BPF_MOD) {
+				PPC_DIVWU(b2p[TMP_REG_1], dst_reg, src_reg);
+				PPC_MULW(b2p[TMP_REG_1], src_reg,
+						b2p[TMP_REG_1]);
+				PPC_SUB(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			} else
+				PPC_DIVWU(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU64 | BPF_DIV | BPF_X: /* dst /= src */
+		case BPF_ALU64 | BPF_MOD | BPF_X: /* dst %= src */
+			PPC_CMPDI(src_reg, 0);
+			PPC_BCC_SHORT(COND_NE, (ctx->idx * 4) + 12);
+			PPC_LI(b2p[BPF_REG_0], 0);
+			PPC_JMP(exit_addr);
+			if (BPF_OP(code) == BPF_MOD) {
+				PPC_DIVD(b2p[TMP_REG_1], dst_reg, src_reg);
+				PPC_MULD(b2p[TMP_REG_1], src_reg,
+						b2p[TMP_REG_1]);
+				PPC_SUB(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			} else
+				PPC_DIVD(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;
+			else if (imm == 1)
+				break;
+			PPC_LI32(b2p[TMP_REG_1], imm);
+			switch (BPF_CLASS(code)) {
+			case BPF_ALU:
+				if (BPF_OP(code) == BPF_MOD) {
+					PPC_DIVWU(b2p[TMP_REG_2], dst_reg,
+							b2p[TMP_REG_1]);
+					PPC_MULW(b2p[TMP_REG_1],
+							b2p[TMP_REG_1],
+							b2p[TMP_REG_2]);
+					PPC_SUB(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+				} else
+					PPC_DIVWU(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+				PPC_CLEAR32();
+				break;
+			case BPF_ALU64:
+				if (BPF_OP(code) == BPF_MOD) {
+					PPC_DIVD(b2p[TMP_REG_2], dst_reg,
+							b2p[TMP_REG_1]);
+					PPC_MULD(b2p[TMP_REG_1],
+							b2p[TMP_REG_1],
+							b2p[TMP_REG_2]);
+					PPC_SUB(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+				} else
+					PPC_DIVD(dst_reg, dst_reg,
+							b2p[TMP_REG_1]);
+			}
+			break;
+		case BPF_ALU | BPF_NEG: /* (u32) dst = -dst */
+		case BPF_ALU64 | BPF_NEG: /* dst = -dst */
+			PPC_NEG(dst_reg, dst_reg);
+			PPC_CLEAR32();
+			break;
+
+		/*
+		 * 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 */
+			PPC_AND(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		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))
+				PPC_ANDI(dst_reg, dst_reg, IMM_L(imm));
+			else {
+				/* Sign-extended */
+				PPC_LI32(b2p[TMP_REG_1], imm);
+				PPC_AND(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			}
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_OR | BPF_X: /* dst = (u32) dst | (u32) src */
+		case BPF_ALU64 | BPF_OR | BPF_X: /* dst = dst | src */
+			PPC_OR(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		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(b2p[TMP_REG_1], imm);
+				PPC_OR(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			} else {
+				if (IMM_L(imm))
+					PPC_ORI(dst_reg, dst_reg, IMM_L(imm));
+				if (IMM_H(imm))
+					PPC_ORIS(dst_reg, dst_reg, IMM_H(imm));
+			}
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_XOR | BPF_X: /* (u32) dst ^= src */
+		case BPF_ALU64 | BPF_XOR | BPF_X: /* dst ^= src */
+			PPC_XOR(dst_reg, dst_reg, src_reg);
+			PPC_CLEAR32();
+			break;
+		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(b2p[TMP_REG_1], imm);
+				PPC_XOR(dst_reg, dst_reg, b2p[TMP_REG_1]);
+			} else {
+				if (IMM_L(imm))
+					PPC_XORI(dst_reg, dst_reg, IMM_L(imm));
+				if (IMM_H(imm))
+					PPC_XORIS(dst_reg, dst_reg, IMM_H(imm));
+			}
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_LSH | BPF_X: /* (u32) dst <<= (u32) src */
+			/* slw clears top 32 bits */
+			PPC_SLW(dst_reg, dst_reg, src_reg);
+			break;
+		case BPF_ALU64 | BPF_LSH | BPF_X: /* dst <<= src; */
+			PPC_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 */
+			PPC_SLWI(dst_reg, dst_reg, imm);
+			break;
+		case BPF_ALU64 | BPF_LSH | BPF_K: /* dst <<== imm */
+			if (imm != 0)
+				PPC_SLDI(dst_reg, dst_reg, imm);
+			break;
+		case BPF_ALU | BPF_RSH | BPF_X: /* (u32) dst >>= (u32) src */
+			PPC_SRW(dst_reg, dst_reg, src_reg);
+			break;
+		case BPF_ALU64 | BPF_RSH | BPF_X: /* dst >>= src */
+			PPC_SRD(dst_reg, dst_reg, src_reg);
+			break;
+		case BPF_ALU | BPF_RSH | BPF_K: /* (u32) dst >>= (u32) imm */
+			PPC_SRWI(dst_reg, dst_reg, imm);
+			break;
+		case BPF_ALU64 | BPF_RSH | BPF_K: /* dst >>= imm */
+			if (imm != 0)
+				PPC_SRDI(dst_reg, dst_reg, imm);
+			break;
+		case BPF_ALU64 | BPF_ARSH | BPF_X: /* (s64) dst >>= src */
+			PPC_SRAD(dst_reg, dst_reg, src_reg);
+			break;
+		case BPF_ALU64 | BPF_ARSH | BPF_K: /* (s64) dst >>= imm */
+			if (imm != 0)
+				PPC_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 */
+			PPC_ADDI(dst_reg, src_reg, 0);
+			PPC_CLEAR32();
+			break;
+		case BPF_ALU | BPF_MOV | BPF_K: /* (u32) dst = imm */
+			PPC_LI32U(dst_reg, imm);
+			break;
+		case BPF_ALU64 | BPF_MOV | BPF_K: /* dst = (s64) imm */
+			PPC_LI32(dst_reg, imm);
+			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 */
+				PPC_RLWINM(b2p[TMP_REG_1], dst_reg, 8, 16, 23);
+				/* Rotate 8 bits right & insert LSB to reg */
+				PPC_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 24, 31);
+				/* Move result back to dst_reg */
+				PPC_ADDI(dst_reg, b2p[TMP_REG_1], 0);
+				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)
+				 */
+				PPC_RLWINM(b2p[TMP_REG_1], dst_reg, 8, 0, 31);
+				/* Rotate 24 bits and insert byte 1 */
+				PPC_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 0, 7);
+				/* Rotate 24 bits and insert byte 3 */
+				PPC_RLWIMI(b2p[TMP_REG_1], dst_reg, 24, 16, 23);
+				PPC_ADDI(dst_reg, b2p[TMP_REG_1], 0);
+				break;
+			case 64:
+				/*
+				 * Way easier and faster to store the value
+				 * into stack and then use ldbrx
+				 *
+				 * First, determine where in stack we can store
+				 * this:
+				 * - if we have allotted a stack frame, then we
+				 *   will utilize the area set aside by
+				 *   BPF_PPC_STACK_LOCALS
+				 * - else, we use the area beneath the NV GPR
+				 *   save area
+				 *
+				 * ctx->seen will be reliable in pass2, but
+				 * the instructions generated will remain the
+				 * same across all passes
+				 */
+				if (bpf_is_seen_register(ctx, BPF_REG_FP) ||
+							ctx->seen & SEEN_FUNC)
+					stack_local_off = STACK_FRAME_MIN_SIZE;
+				else
+					stack_local_off = -(BPF_PPC_STACK_SAVE +
+								8);
+
+				PPC_STD(dst_reg, 1, stack_local_off);
+				PPC_ADDI(b2p[TMP_REG_1], 1, stack_local_off);
+				PPC_LDBRX(dst_reg, 0, b2p[TMP_REG_1]);
+				break;
+			}
+			break;
+emit_clear:
+			switch (imm) {
+			case 16:
+				/* zero-extend 16 bits into 64 bits */
+				PPC_RLDICL(dst_reg, dst_reg, 0, 48);
+				break;
+			case 32:
+				/* zero-extend 32 bits into 64 bits */
+				PPC_RLDICL(dst_reg, dst_reg, 0, 32);
+				break;
+			case 64:
+				/* nop */
+				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) {
+				PPC_LI(b2p[TMP_REG_1], imm);
+				src_reg = b2p[TMP_REG_1];
+			}
+			PPC_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) {
+				PPC_LI(b2p[TMP_REG_1], imm);
+				src_reg = b2p[TMP_REG_1];
+			}
+			PPC_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(b2p[TMP_REG_1], imm);
+				src_reg = b2p[TMP_REG_1];
+			}
+			PPC_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(b2p[TMP_REG_1], imm);
+				src_reg = b2p[TMP_REG_1];
+			}
+			PPC_STD(src_reg, dst_reg, off);
+			break;
+
+		/*
+		 * BPF_STX XADD (atomic_add)
+		 */
+		/* *(u32 *)(dst + off) += src */
+		case BPF_STX | BPF_XADD | BPF_W:
+			/* Get EA into TMP_REG_1 */
+			PPC_ADDI(b2p[TMP_REG_1], dst_reg, off);
+			/* error if EA is not word-aligned */
+			PPC_ANDI(b2p[TMP_REG_2], b2p[TMP_REG_1], 0x03);
+			PPC_BCC_SHORT(COND_EQ, (ctx->idx * 4) + 12);
+			PPC_LI(b2p[BPF_REG_0], 0);
+			PPC_JMP(exit_addr);
+			/* load value from memory into TMP_REG_2 */
+			PPC_LWARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0);
+			/* add value from src_reg into this */
+			PPC_ADD(b2p[TMP_REG_2], b2p[TMP_REG_2], src_reg);
+			/* store result back */
+			PPC_STWCX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1]);
+			break;
+		/* *(u64 *)(dst + off) += src */
+		case BPF_STX | BPF_XADD | BPF_DW:
+			PPC_ADDI(b2p[TMP_REG_1], dst_reg, off);
+			/* error if EA is not doubleword-aligned */
+			PPC_ANDI(b2p[TMP_REG_2], b2p[TMP_REG_1], 0x07);
+			PPC_BCC_SHORT(COND_EQ, (ctx->idx * 4) + 12);
+			PPC_LI(b2p[BPF_REG_0], 0);
+			PPC_JMP(exit_addr);
+			PPC_LDARX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1], 0);
+			PPC_ADD(b2p[TMP_REG_2], b2p[TMP_REG_2], src_reg);
+			PPC_STDCX(b2p[TMP_REG_2], 0, b2p[TMP_REG_1]);
+			break;
+
+		/*
+		 * BPF_LDX
+		 */
+		/* dst = *(u8 *)(ul) (src + off) */
+		case BPF_LDX | BPF_MEM | BPF_B:
+			PPC_LBZ(dst_reg, src_reg, off);
+			break;
+		/* dst = *(u16 *)(ul) (src + off) */
+		case BPF_LDX | BPF_MEM | BPF_H:
+			PPC_LHZ(dst_reg, src_reg, off);
+			break;
+		/* dst = *(u32 *)(ul) (src + off) */
+		case BPF_LDX | BPF_MEM | BPF_W:
+			PPC_LWZ(dst_reg, src_reg, off);
+			break;
+		/* dst = *(u64 *)(ul) (src + off) */
+		case BPF_LDX | BPF_MEM | BPF_DW:
+			PPC_LD(dst_reg, src_reg, off);
+			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);
+			/* Adjust for two bpf instructions */
+			addrs[++i] = ctx->idx * 4;
+			PPC_LI64(dst_reg, imm64);
+			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)
+				PPC_JMP(exit_addr);
+			/* else fall through to the epilogue */
+			break;
+
+		/*
+		 * Call kernel helper
+		 */
+		case BPF_JMP | BPF_CALL:
+			ctx->seen |= SEEN_FUNC;
+			func = (u8 *) __bpf_call_base + imm;
+			if (bpf_helper_changes_skb_data(func))
+				return -ENOTSUPP; /* TODO */
+#if !defined(_CALL_ELF) || _CALL_ELF != 2
+			/* func points to the function descriptor */
+			PPC_LI64(b2p[TMP_REG_2], (u64)func);
+			/* Load actual entry point from function descriptor */
+			PPC_BPF_LL(b2p[TMP_REG_1], b2p[TMP_REG_2], 0);
+			/* Load TOC from function descriptor at offset 8*/
+			PPC_BPF_LL(2, b2p[TMP_REG_2], 8);
+			/* Load function entry point to LR */
+			PPC_MTLR(b2p[TMP_REG_1]);
+#elif defined(_CALL_ELF) && _CALL_ELF == 2
+			/* we can clobber r12 */
+			PPC_FUNC_ADDR(12, func);
+			PPC_MTLR(12);
+#endif
+			PPC_BLRL();
+			/* move return value from r3 to BPF_REG_0 */
+			PPC_ADDI(b2p[BPF_REG_0], 3, 0);
+			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:
+			true_cond = COND_GT;
+			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:
+			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_JNE | BPF_K:
+		case BPF_JMP | 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:
+			true_cond = COND_NE;
+			/* Fall through */
+
+cond_branch:
+			switch (code) {
+			case BPF_JMP | BPF_JGT | BPF_X:
+			case BPF_JMP | BPF_JGE | BPF_X:
+			case BPF_JMP | BPF_JEQ | BPF_X:
+			case BPF_JMP | BPF_JNE | BPF_X:
+				/* unsigned comparison */
+				PPC_CMPLD(dst_reg, src_reg);
+				break;
+			case BPF_JMP | BPF_JSGT | BPF_X:
+			case BPF_JMP | BPF_JSGE | BPF_X:
+				/* signed comparison */
+				PPC_CMPD(dst_reg, src_reg);
+				break;
+			case BPF_JMP | BPF_JSET | BPF_X:
+				PPC_AND_DOT(b2p[TMP_REG_1], 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_JGE | BPF_K:
+				/*
+				 * Need sign-extended load, so only positive
+				 * values can be used as imm in cmpldi
+				 */
+				if (imm >= 0 && imm < 32768)
+					PPC_CMPLDI(dst_reg, imm);
+				else {
+					/* sign-extending load */
+					PPC_LI32(b2p[TMP_REG_1], imm);
+					/* ... but unsigned comparison */
+					PPC_CMPLD(dst_reg, b2p[TMP_REG_1]);
+				}
+				break;
+			case BPF_JMP | BPF_JSGT | BPF_K:
+			case BPF_JMP | BPF_JSGE | BPF_K:
+				/*
+				 * signed comparison, so any 16-bit value
+				 * can be used in cmpdi
+				 */
+				if (imm >= -32768 && imm < 32768)
+					PPC_CMPDI(dst_reg, imm);
+				else {
+					PPC_LI32(b2p[TMP_REG_1], imm);
+					PPC_CMPD(dst_reg, b2p[TMP_REG_1]);
+				}
+				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 */
+					PPC_ANDI(b2p[TMP_REG_1], dst_reg, imm);
+				else {
+					PPC_LI32(b2p[TMP_REG_1], imm);
+					PPC_AND_DOT(b2p[TMP_REG_1], dst_reg,
+						    b2p[TMP_REG_1]);
+				}
+				break;
+			}
+			PPC_BCC(true_cond, addrs[i + 1 + off]);
+			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;
+}
+
+void bpf_jit_compile(struct bpf_prog *fp) { }
+
+void bpf_int_jit_compile(struct bpf_prog *fp)
+{
+	u32 proglen;
+	u32 alloclen;
+	u32 *image = NULL;
+	u32 *code_base;
+	u32 *addrs;
+	struct codegen_context cgctx;
+	int pass;
+	int flen;
+
+	if (!bpf_jit_enable)
+		return;
+
+	if (!fp || !fp->len)
+		return;
+
+	flen = fp->len;
+	addrs = kzalloc((flen+1) * sizeof(*addrs), GFP_KERNEL);
+	if (addrs == NULL)
+		return;
+
+	cgctx.idx = 0;
+	cgctx.seen = 0;
+	/* 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);
+
+	if (image) {
+		flush_icache_range((unsigned long)code_base,
+				(unsigned long)(code_base + (proglen/4)));
+#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)
+		/* 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);
+}
+
+void bpf_jit_free(struct bpf_prog *fp)
+{
+	if (fp->jited)
+		module_memfree(fp->bpf_func);
+
+	bpf_prog_unlock_free(fp);
+}
-- 
2.7.4

Re: [RFC PATCH 0/6] eBPF JIT for PPC64

[Naveen N. Rao]

On 2016/04/01 03:28PM, Naveen N Rao wrote:
> Implement extended BPF JIT for ppc64. We retain the classic BPF JIT for
> ppc32 and move ppc64 BE/LE to use the new JIT. Classic BPF filters will
> be converted to extended BPF (see convert_filter()) and JIT'ed with the
> new compiler.
> 
> Most of the existing macros are retained and fixed/enhanced where
> appropriate. Patches 1-4 are geared towards this.
> 
> Patch 5 breaks out the classic BPF JIT specifics into a separate
> bpf_jit32.h header file, while retaining all the generic instruction
> macros in bpf_jit.h. Most of these macros can potentially be generalized
> and moved to more common code (tagged with a TODO in patch 6).
> 
> Patch 6 implements eBPF JIT for ppc64.

As a comparison, here are the test results with the BPF test suite 
kernel module:

With the classic BPF JIT:
test_bpf: Summary: 291 PASSED, 0 FAILED, [85/283 JIT'ed]

and with the extended BPF JIT:
test_bpf: Summary: 291 PASSED, 0 FAILED, [234/283 JIT'ed]

As noted in patch 6, there are still a few more instructions to be 
JIT'ed.


- Naveen

Re: [RFC PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

[Alexei Starovoitov]

On 4/1/16 2:58 AM, Naveen N. Rao wrote:
> PPC64 eBPF JIT compiler. Works for both ABIv1 and ABIv2.
>
> Enable with:
> echo 1 > /proc/sys/net/core/bpf_jit_enable
> or
> echo 2 > /proc/sys/net/core/bpf_jit_enable
>
> ... to see the generated JIT code. This can further be processed with
> tools/net/bpf_jit_disasm.
>
> With CONFIG_TEST_BPF=m and 'modprobe test_bpf':
> test_bpf: Summary: 291 PASSED, 0 FAILED, [234/283 JIT'ed]
>
> ... on both ppc64 BE and LE.
>
> The details of the approach are documented through various comments in
> the code, as are the TODOs. Some of the prominent TODOs include
> implementing BPF tail calls and skb loads.
>
> Cc: Matt Evans <matt@ozlabs.org>
> Cc: Michael Ellerman <mpe@ellerman.id.au>
> Cc: Paul Mackerras <paulus@samba.org>
> Cc: Alexei Starovoitov <ast@fb.com>
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> ---
>   arch/powerpc/include/asm/ppc-opcode.h |  19 +-
>   arch/powerpc/net/Makefile             |   4 +
>   arch/powerpc/net/bpf_jit.h            |  66 ++-
>   arch/powerpc/net/bpf_jit64.h          |  58 +++
>   arch/powerpc/net/bpf_jit_comp64.c     | 828 ++++++++++++++++++++++++++++++++++
>   5 files changed, 973 insertions(+), 2 deletions(-)
>   create mode 100644 arch/powerpc/net/bpf_jit64.h
>   create mode 100644 arch/powerpc/net/bpf_jit_comp64.c
...
> -#ifdef CONFIG_PPC64
> +#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)

impressive stuff!
Everything nicely documented. Could you add few words for the above
condition as well ?
Or may be a new macro, since it occurs many times?
What are these _CALL_ELF == 2 and != 2 conditions mean? ppc ABIs ?
Will there ever be v3 ?

So far most of the bpf jits were going via net-next tree, but if
in this case no changes to the core is necessary then I guess it's fine
to do it via powerpc tree. What's your plan?

Re: [RFC PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

[Daniel Borkmann]

On 04/01/2016 08:10 PM, Alexei Starovoitov wrote:
> On 4/1/16 2:58 AM, Naveen N. Rao wrote:
>> PPC64 eBPF JIT compiler. Works for both ABIv1 and ABIv2.
>>
>> Enable with:
>> echo 1 > /proc/sys/net/core/bpf_jit_enable
>> or
>> echo 2 > /proc/sys/net/core/bpf_jit_enable
>>
>> ... to see the generated JIT code. This can further be processed with
>> tools/net/bpf_jit_disasm.
>>
>> With CONFIG_TEST_BPF=m and 'modprobe test_bpf':
>> test_bpf: Summary: 291 PASSED, 0 FAILED, [234/283 JIT'ed]
>>
>> ... on both ppc64 BE and LE.
>>
>> The details of the approach are documented through various comments in
>> the code, as are the TODOs. Some of the prominent TODOs include
>> implementing BPF tail calls and skb loads.
>>
>> Cc: Matt Evans <matt@ozlabs.org>
>> Cc: Michael Ellerman <mpe@ellerman.id.au>
>> Cc: Paul Mackerras <paulus@samba.org>
>> Cc: Alexei Starovoitov <ast@fb.com>
>> Cc: "David S. Miller" <davem@davemloft.net>
>> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
>> Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
>> ---
>>   arch/powerpc/include/asm/ppc-opcode.h |  19 +-
>>   arch/powerpc/net/Makefile             |   4 +
>>   arch/powerpc/net/bpf_jit.h            |  66 ++-
>>   arch/powerpc/net/bpf_jit64.h          |  58 +++
>>   arch/powerpc/net/bpf_jit_comp64.c     | 828 ++++++++++++++++++++++++++++++++++
>>   5 files changed, 973 insertions(+), 2 deletions(-)
>>   create mode 100644 arch/powerpc/net/bpf_jit64.h
>>   create mode 100644 arch/powerpc/net/bpf_jit_comp64.c
> ...
>> -#ifdef CONFIG_PPC64
>> +#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)
>
> impressive stuff!

+1, awesome to see another one!

> Everything nicely documented. Could you add few words for the above
> condition as well ?
> Or may be a new macro, since it occurs many times?
> What are these _CALL_ELF == 2 and != 2 conditions mean? ppc ABIs ?
> Will there ever be v3 ?

Minor TODO would also be to convert to use bpf_jit_binary_alloc() and
bpf_jit_binary_free() API for the image, which is done by other eBPF
jits, too.

> So far most of the bpf jits were going via net-next tree, but if
> in this case no changes to the core is necessary then I guess it's fine
> to do it via powerpc tree. What's your plan?
>

Re: [RFC PATCH 6/6] ppc: ebpf/jit: Implement JIT compiler for extended BPF

[Naveen N. Rao]

On 2016/04/01 08:34PM, Daniel Borkmann wrote:
> On 04/01/2016 08:10 PM, Alexei Starovoitov wrote:
> >On 4/1/16 2:58 AM, Naveen N. Rao wrote:
> >>PPC64 eBPF JIT compiler. Works for both ABIv1 and ABIv2.
> >>
> >>Enable with:
> >>echo 1 > /proc/sys/net/core/bpf_jit_enable
> >>or
> >>echo 2 > /proc/sys/net/core/bpf_jit_enable
> >>
> >>... to see the generated JIT code. This can further be processed with
> >>tools/net/bpf_jit_disasm.
> >>
> >>With CONFIG_TEST_BPF=m and 'modprobe test_bpf':
> >>test_bpf: Summary: 291 PASSED, 0 FAILED, [234/283 JIT'ed]
> >>
> >>... on both ppc64 BE and LE.
> >>
> >>The details of the approach are documented through various comments in
> >>the code, as are the TODOs. Some of the prominent TODOs include
> >>implementing BPF tail calls and skb loads.
> >>
> >>Cc: Matt Evans <matt@ozlabs.org>
> >>Cc: Michael Ellerman <mpe@ellerman.id.au>
> >>Cc: Paul Mackerras <paulus@samba.org>
> >>Cc: Alexei Starovoitov <ast@fb.com>
> >>Cc: "David S. Miller" <davem@davemloft.net>
> >>Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
> >>Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
> >>---
> >>  arch/powerpc/include/asm/ppc-opcode.h |  19 +-
> >>  arch/powerpc/net/Makefile             |   4 +
> >>  arch/powerpc/net/bpf_jit.h            |  66 ++-
> >>  arch/powerpc/net/bpf_jit64.h          |  58 +++
> >>  arch/powerpc/net/bpf_jit_comp64.c     | 828 ++++++++++++++++++++++++++++++++++
> >>  5 files changed, 973 insertions(+), 2 deletions(-)
> >>  create mode 100644 arch/powerpc/net/bpf_jit64.h
> >>  create mode 100644 arch/powerpc/net/bpf_jit_comp64.c
> >...
> >>-#ifdef CONFIG_PPC64
> >>+#if defined(CONFIG_PPC64) && (!defined(_CALL_ELF) || _CALL_ELF != 2)
> >
> >impressive stuff!
> 
> +1, awesome to see another one!

Thanks!

> 
> >Everything nicely documented. Could you add few words for the above
> >condition as well ?
> >Or may be a new macro, since it occurs many times?
> >What are these _CALL_ELF == 2 and != 2 conditions mean? ppc ABIs ?

Yes, there are 2 ABIs: ppc64 (ABIv1) -- big endian and the recently 
introduced ppc64le (ABIv2) which is currently only little endian. There 
is also ppc32...

Good suggestion about using a macro. I will put out a patch for that.

> >Will there ever be v3 ?

Hope not! ;)

> 
> Minor TODO would also be to convert to use bpf_jit_binary_alloc() and
> bpf_jit_binary_free() API for the image, which is done by other eBPF
> jits, too.

Sure. I will make that change.

> 
> >So far most of the bpf jits were going via net-next tree, but if
> >in this case no changes to the core is necessary then I guess it's fine
> >to do it via powerpc tree. What's your plan?

I initially thought this has to go through the powerpc tree. I don't 
really have a preference and I'll allow the maintainers to take a call 
on that. I do however need a review of the JIT code from Michael
Ellerman/Paul Mackerras.


- Naveen