From 9f596e51261f96d602aa4eaf6db7f12ce53260d6 Mon Sep 17 00:00:00 2001 From: Jon Medhurst Date: Thu, 9 Jun 2011 17:35:36 +0100 Subject: [PATCH] ARM: kprobes: Add emulate_rd12rn16rm0rs8_rwflags() This is the emulation function for the instruction format used by the ARM data-processing instructions. Signed-off-by: Jon Medhurst Acked-by: Nicolas Pitre --- arch/arm/kernel/kprobes-arm.c | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/arch/arm/kernel/kprobes-arm.c b/arch/arm/kernel/kprobes-arm.c index 80a9411..6e38bd4 100644 --- a/arch/arm/kernel/kprobes-arm.c +++ b/arch/arm/kernel/kprobes-arm.c @@ -893,6 +893,41 @@ prep_emulate_rdhi16rdlo12rs8rm0_wflags(kprobe_opcode_t insn, return INSN_GOOD; } +static void __kprobes +emulate_rd12rn16rm0rs8_rwflags(struct kprobe *p, struct pt_regs *regs) +{ + kprobe_opcode_t insn = p->opcode; + unsigned long pc = (unsigned long)p->addr + 8; + int rd = (insn >> 12) & 0xf; + int rn = (insn >> 16) & 0xf; + int rm = insn & 0xf; + int rs = (insn >> 8) & 0xf; + + register unsigned long rdv asm("r0") = regs->uregs[rd]; + register unsigned long rnv asm("r2") = (rn == 15) ? pc + : regs->uregs[rn]; + register unsigned long rmv asm("r3") = (rm == 15) ? pc + : regs->uregs[rm]; + register unsigned long rsv asm("r1") = regs->uregs[rs]; + unsigned long cpsr = regs->ARM_cpsr; + + __asm__ __volatile__ ( + "msr cpsr_fs, %[cpsr] \n\t" + BLX("%[fn]") + "mrs %[cpsr], cpsr \n\t" + : "=r" (rdv), [cpsr] "=r" (cpsr) + : "0" (rdv), "r" (rnv), "r" (rmv), "r" (rsv), + "1" (cpsr), [fn] "r" (p->ainsn.insn_fn) + : "lr", "memory", "cc" + ); + + if (rd == 15) + alu_write_pc(rdv, regs); + else + regs->uregs[rd] = rdv; + regs->ARM_cpsr = (regs->ARM_cpsr & ~APSR_MASK) | (cpsr & APSR_MASK); +} + /* * For the instruction masking and comparisons in all the "space_*" * functions below, Do _not_ rearrange the order of tests unless -- 2.7.4