diff rfc→v3 (patch 1) | series

Inter-revision diff: patch 1

Comparing rfc (message) to v3 (message)
--- vrfc
+++ v3
@@ -1,167 +1,56 @@
-Detour buffer contains instructions to create an in memory pt_regs.
-After the execution of prehandler a call is made for instruction emulation.
-The NIP is decided after the probed instruction is executed. Hence a branch
-instruction is created to the NIP returned by emulate_step().
+From: "Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>
 
-Signed-off-by: Anju T <anju@linux.vnet.ibm.com>
+Introduce __PPC_SH64() as a 64-bit variant to encode shift field in some
+of the shift and rotate instructions operating on double-words. Convert
+some of the BPF instruction macros to use the same.
+
+Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
 ---
- arch/powerpc/include/asm/kprobes.h   |  25 +++++++++
- arch/powerpc/kernel/optprobes_head.S | 104 +++++++++++++++++++++++++++++++++++
- 2 files changed, 129 insertions(+)
- create mode 100644 arch/powerpc/kernel/optprobes_head.S
+ arch/powerpc/include/asm/ppc-opcode.h |  1 +
+ arch/powerpc/net/bpf_jit.h            | 11 +++++------
+ 2 files changed, 6 insertions(+), 6 deletions(-)
 
-diff --git a/arch/powerpc/include/asm/kprobes.h b/arch/powerpc/include/asm/kprobes.h
-index 039b583..3e4c998 100644
---- a/arch/powerpc/include/asm/kprobes.h
-+++ b/arch/powerpc/include/asm/kprobes.h
-@@ -38,7 +38,25 @@ struct pt_regs;
- struct kprobe;
+diff --git a/arch/powerpc/include/asm/ppc-opcode.h b/arch/powerpc/include/asm/ppc-opcode.h
+index 0132831..630127b 100644
+--- a/arch/powerpc/include/asm/ppc-opcode.h
++++ b/arch/powerpc/include/asm/ppc-opcode.h
+@@ -306,6 +306,7 @@
+ #define __PPC_WC(w)	(((w) & 0x3) << 21)
+ #define __PPC_WS(w)	(((w) & 0x1f) << 11)
+ #define __PPC_SH(s)	__PPC_WS(s)
++#define __PPC_SH64(s)	(__PPC_SH(s) | (((s) & 0x20) >> 4))
+ #define __PPC_MB(s)	(((s) & 0x1f) << 6)
+ #define __PPC_ME(s)	(((s) & 0x1f) << 1)
+ #define __PPC_MB64(s)	(__PPC_MB(s) | ((s) & 0x20))
+diff --git a/arch/powerpc/net/bpf_jit.h b/arch/powerpc/net/bpf_jit.h
+index 89f7007..30cf03f 100644
+--- a/arch/powerpc/net/bpf_jit.h
++++ b/arch/powerpc/net/bpf_jit.h
+@@ -157,8 +157,7 @@
+ #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))
++				     ___PPC_RS(a) | __PPC_SH64(i))
+ #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))
+@@ -166,11 +165,11 @@
+ 					___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))
++					___PPC_RS(a) | __PPC_SH64(i) |	      \
++					__PPC_MB64(mb))
+ #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))
++					___PPC_RS(a) | __PPC_SH64(i) |	      \
++					__PPC_ME64(me))
  
- typedef ppc_opcode_t kprobe_opcode_t;
-+
-+extern kprobe_opcode_t optinsn_slot;
-+/* Optinsn template address */
-+extern kprobe_opcode_t optprobe_template_entry[];
-+extern kprobe_opcode_t optprobe_template_call_handler[];
-+extern kprobe_opcode_t optprobe_template_call_emulate[];
-+extern kprobe_opcode_t optprobe_template_ret_branch[];
-+extern kprobe_opcode_t optprobe_template_ret[];
-+extern kprobe_opcode_t optprobe_template_insn[];
-+extern kprobe_opcode_t optprobe_template_op_address1[];
-+extern kprobe_opcode_t optprobe_template_op_address2[];
-+extern kprobe_opcode_t optprobe_template_end[];
-+
- #define MAX_INSN_SIZE 1
-+#define MAX_OPTIMIZED_LENGTH    4
-+#define MAX_OPTINSN_SIZE				\
-+	((unsigned long)&optprobe_template_end -	\
-+	(unsigned long)&optprobe_template_entry)
-+#define RELATIVEJUMP_SIZE       4
- 
- #ifdef CONFIG_PPC64
- #if defined(_CALL_ELF) && _CALL_ELF == 2
-@@ -129,5 +147,12 @@ struct kprobe_ctlblk {
- extern int kprobe_exceptions_notify(struct notifier_block *self,
- 					unsigned long val, void *data);
- extern int kprobe_fault_handler(struct pt_regs *regs, int trapnr);
-+
-+struct arch_optimized_insn {
-+	kprobe_opcode_t copied_insn[1];
-+	/* detour buffer */
-+	kprobe_opcode_t *insn;
-+};
-+
- #endif /* __KERNEL__ */
- #endif	/* _ASM_POWERPC_KPROBES_H */
-diff --git a/arch/powerpc/kernel/optprobes_head.S b/arch/powerpc/kernel/optprobes_head.S
-new file mode 100644
-index 0000000..025bab7
---- /dev/null
-+++ b/arch/powerpc/kernel/optprobes_head.S
-@@ -0,0 +1,104 @@
-+/*
-+ * Code to prepare detour buffer for optprobes in kernel.
-+ *
-+ * Copyright 2016, Anju T, IBM Corp.
-+ *
-+ * 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; either version
-+ * 2 of the License, or (at your option) any later version.
-+ */
-+
-+#include <asm/ppc_asm.h>
-+#include <asm/ptrace.h>
-+#include <asm/asm-offsets.h>
-+
-+.global optprobe_template_entry
-+optprobe_template_entry:
-+	stdu	r1,-INT_FRAME_SIZE(r1)
-+	SAVE_GPR(0,r1)
-+	/* Save the previous SP into stack */
-+	addi	r0,r1,INT_FRAME_SIZE
-+	std	0,GPR1(r1)
-+	SAVE_2GPRS(2,r1)
-+	SAVE_8GPRS(4,r1)
-+	SAVE_10GPRS(12,r1)
-+	SAVE_10GPRS(22,r1)
-+	/* Save SPRS */
-+	mfcfar	r5
-+	std	r5,_NIP(r1)
-+	mfmsr	r5
-+	std	r5,_MSR(r1)
-+	mfctr	r5
-+	std	r5,_CTR(r1)
-+	mflr	r5
-+	std	r5,_LINK(r1)
-+	mfspr	r5,SPRN_XER
-+	std	r5,_XER(r1)
-+	li	r5,0
-+	std	r5,_TRAP(r1)
-+	mfdar	r5
-+	std	r5,_DAR(r1)
-+	mfdsisr	r5
-+	std	r5,_DSISR(r1)
-+	/* Pass parameters for optimized_callback */
-+.global optprobe_template_op_address1
-+optprobe_template_op_address1:
-+	nop
-+	nop
-+	nop
-+	nop
-+	nop
-+	addi	r4,r1,STACK_FRAME_OVERHEAD
-+	/* Branch to the prehandler */
-+.global optprobe_template_call_handler
-+optprobe_template_call_handler:
-+	nop
-+	/* Pass parameters for instruction emulation */
-+	addi	r3,r1,STACK_FRAME_OVERHEAD
-+.global optprobe_template_insn
-+optprobe_template_insn:
-+	nop
-+	nop
-+	/* Branch to instruction emulation  */
-+.global optprobe_template_call_emulate
-+optprobe_template_call_emulate:
-+	nop
-+.global optprobe_template_op_address2
-+optprobe_template_op_address2:
-+	nop
-+	nop
-+	nop
-+	nop
-+	nop
-+	addi	r4,r1,STACK_FRAME_OVERHEAD
-+	/* Branch to create_return_branch() function */
-+.global optprobe_template_ret_branch
-+optprobe_template_ret_branch:
-+	nop
-+	/* Restore the registers */
-+	ld	r5,_MSR(r1)
-+	mtmsr	r5
-+	ld	r5,_CTR(r1)
-+	mtctr	r5
-+	ld	r5,_LINK(r1)
-+	mtlr	r5
-+	ld	r5,_XER(r1)
-+	mtxer	r5
-+	ld	r5,_DAR(r1)
-+	mtdar	r5
-+	ld	r5,_DSISR(r1)
-+	mtdsisr	r5
-+	REST_GPR(0,r1)
-+	REST_2GPRS(2,r1)
-+	REST_8GPRS(4,r1)
-+	REST_10GPRS(12,r1)
-+	REST_10GPRS(22,r1)
-+	/* Restore the previous SP */
-+	addi	r1,r1,INT_FRAME_SIZE
-+	/* Jump back to the normal workflow from trampoline */
-+.global optprobe_template_ret
-+optprobe_template_ret:
-+	nop
-+.global optprobe_template_end
-+optprobe_template_end:
+ /* slwi = rlwinm Rx, Ry, n, 0, 31-n */
+ #define PPC_SLWI(d, a, i)	PPC_RLWINM(d, a, i, 0, 31-(i))
 -- 
-2.1.0
+2.7.4
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