ARM: kprobes: Migrate ARM space_cccc_001x to decoding tables

Signed-off-by: Jon Medhurst <tixy@yxit.co.uk>
Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org>

diff --git a/arch/arm/kernel/kprobes-arm.c b/arch/arm/kernel/kprobes-arm.c
index ef350a5..f2eed03 100644 (file)
--- a/arch/arm/kernel/kprobes-arm.c
+++ b/arch/arm/kernel/kprobes-arm.c
@@ -1203,72 +1203,56 @@ space_cccc_000x(kprobe_opcode_t insn, struct arch_specific_insn *asi)
        return kprobe_decode_insn(insn, asi, arm_cccc_000x_table, false);
 }
 
-static enum kprobe_insn __kprobes
-space_cccc_001x(kprobe_opcode_t insn, struct arch_specific_insn *asi)
-{
-       /* MOVW  : cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
-       /* MOVT  : cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
-       if ((insn & 0x0fb00000) == 0x03000000)
-               return prep_emulate_rd12_modify(insn, asi);
-
-       /* hints : cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
-       if ((insn & 0x0fff0000) == 0x03200000) {
-               unsigned op2 = insn & 0x000000ff;
-               if (op2 == 0x01 || op2 == 0x04) {
-                       /* YIELD : cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
-                       /* SEV   : cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
-                       asi->insn[0] = insn;
-                       asi->insn_handler = emulate_none;
-                       return INSN_GOOD;
-               } else if (op2 <= 0x03) {
-                       /* NOP   : cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
-                       /* WFE   : cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
-                       /* WFI   : cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
-                       /*
-                        * We make WFE and WFI true NOPs to avoid stalls due
-                        * to missing events whilst processing the probe.
-                        */
-                       asi->insn_handler = emulate_nop;
-                       return INSN_GOOD_NO_SLOT;
-               }
-               /* For DBG and unallocated hints it's safest to reject them */
-               return INSN_REJECTED;
-       }
+static const union decode_item arm_cccc_001x_table[] = {
+       /* Data-processing (immediate)                                  */
+
+       /* MOVW                 cccc 0011 0000 xxxx xxxx xxxx xxxx xxxx */
+       /* MOVT                 cccc 0011 0100 xxxx xxxx xxxx xxxx xxxx */
+       DECODE_CUSTOM   (0x0fb00000, 0x03000000, prep_emulate_rd12_modify),
+
+       /* YIELD                cccc 0011 0010 0000 xxxx xxxx 0000 0001 */
+       DECODE_OR       (0x0fff00ff, 0x03200001),
+       /* SEV                  cccc 0011 0010 0000 xxxx xxxx 0000 0100 */
+       DECODE_EMULATE  (0x0fff00ff, 0x03200004, kprobe_emulate_none),
+       /* NOP                  cccc 0011 0010 0000 xxxx xxxx 0000 0000 */
+       /* WFE                  cccc 0011 0010 0000 xxxx xxxx 0000 0010 */
+       /* WFI                  cccc 0011 0010 0000 xxxx xxxx 0000 0011 */
+       DECODE_SIMULATE (0x0fff00fc, 0x03200000, kprobe_simulate_nop),
+       /* DBG                  cccc 0011 0010 0000 xxxx xxxx ffff xxxx */
+       /* unallocated hints    cccc 0011 0010 0000 xxxx xxxx xxxx xxxx */
+       /* MSR (immediate)      cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx */
+       DECODE_REJECT   (0x0fb00000, 0x03200000),
+
+       /* <op>S PC, ...        cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx */
+       DECODE_REJECT   (0x0e10f000, 0x0210f000),
+
+       /* TST (immediate)      cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx */
+       /* TEQ (immediate)      cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx */
+       /* CMP (immediate)      cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx */
+       /* CMN (immediate)      cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx */
+       DECODE_EMULATEX (0x0f900000, 0x03100000, emulate_rd12rn16rm0rs8_rwflags,
+                                                REGS(ANY, 0, 0, 0, 0)),
+
+       /* MOV (immediate)      cccc 0011 101x xxxx xxxx xxxx xxxx xxxx */
+       /* MVN (immediate)      cccc 0011 111x xxxx xxxx xxxx xxxx xxxx */
+       DECODE_EMULATEX (0x0fa00000, 0x03a00000, emulate_rd12rn16rm0rs8_rwflags,
+                                                REGS(0, ANY, 0, 0, 0)),
+
+       /* AND (immediate)      cccc 0010 000x xxxx xxxx xxxx xxxx xxxx */
+       /* EOR (immediate)      cccc 0010 001x xxxx xxxx xxxx xxxx xxxx */
+       /* SUB (immediate)      cccc 0010 010x xxxx xxxx xxxx xxxx xxxx */
+       /* RSB (immediate)      cccc 0010 011x xxxx xxxx xxxx xxxx xxxx */
+       /* ADD (immediate)      cccc 0010 100x xxxx xxxx xxxx xxxx xxxx */
+       /* ADC (immediate)      cccc 0010 101x xxxx xxxx xxxx xxxx xxxx */
+       /* SBC (immediate)      cccc 0010 110x xxxx xxxx xxxx xxxx xxxx */
+       /* RSC (immediate)      cccc 0010 111x xxxx xxxx xxxx xxxx xxxx */
+       /* ORR (immediate)      cccc 0011 100x xxxx xxxx xxxx xxxx xxxx */
+       /* BIC (immediate)      cccc 0011 110x xxxx xxxx xxxx xxxx xxxx */
+       DECODE_EMULATEX (0x0e000000, 0x02000000, emulate_rd12rn16rm0rs8_rwflags,
+                                                REGS(ANY, ANY, 0, 0, 0)),
 
-       /*
-        * MSR   : cccc 0011 0x10 xxxx xxxx xxxx xxxx xxxx
-        * ALU op with S bit and Rd == 15 :
-        *         cccc 001x xxx1 xxxx 1111 xxxx xxxx xxxx
-        */
-       if ((insn & 0x0fb00000) == 0x03200000 ||        /* MSR */
-           (insn & 0x0e10f000) == 0x0210f000)          /* ALU s-bit, R15  */
-               return INSN_REJECTED;
-
-       /*
-        * Data processing: 32-bit Immediate
-        * ALU op : cccc 001x xxxx xxxx xxxx xxxx xxxx xxxx
-        * MOV    : cccc 0011 101x xxxx xxxx xxxx xxxx xxxx
-        * *S (bit 20) updates condition codes
-        * ADC/SBC/RSC reads the C flag
-        */
-       insn &= 0xfff00fff;     /* Rn = r0 and Rd = r0 */
-       asi->insn[0] = insn;
-
-       if ((insn & 0x0f900000) == 0x03100000) {
-               /*
-                * TST : cccc 0011 0001 xxxx xxxx xxxx xxxx xxxx
-                * TEQ : cccc 0011 0011 xxxx xxxx xxxx xxxx xxxx
-                * CMP : cccc 0011 0101 xxxx xxxx xxxx xxxx xxxx
-                * CMN : cccc 0011 0111 xxxx xxxx xxxx xxxx xxxx
-                */
-               asi->insn_handler = emulate_alu_tests_imm;
-       } else {
-               /* ALU ops which write to Rd */
-               asi->insn_handler = (insn & (1 << 20)) ?  /* S-bit */
-                       emulate_alu_imm_rwflags : emulate_alu_imm_rflags;
-       }
-       return INSN_GOOD;
-}
+       DECODE_END
+};
 
 static enum kprobe_insn __kprobes
 space_cccc_0110__1(kprobe_opcode_t insn, struct arch_specific_insn *asi)
@@ -1548,7 +1532,7 @@ arm_kprobe_decode_insn(kprobe_opcode_t insn, struct arch_specific_insn *asi)
 
        else if ((insn & 0x0e000000) == 0x02000000)
 
-               return space_cccc_001x(insn, asi);
+               return kprobe_decode_insn(insn, asi, arm_cccc_001x_table, false);
 
        else if ((insn & 0x0f000010) == 0x06000010)