From d6d4509a9f326fd90fe47e33fe532c7bc2c8adf2 Mon Sep 17 00:00:00 2001 From: Warner Losh Date: Thu, 23 Sep 2021 15:23:13 -0600 Subject: [PATCH] bsd-user/arm/signal.c: arm set_mcontext Move the machine context to the CPU state. Signed-off-by: Stacey Son Signed-off-by: Kyle Evans Signed-off-by: Warner Losh Reviewed-by: Richard Henderson --- bsd-user/arm/signal.c | 76 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) diff --git a/bsd-user/arm/signal.c b/bsd-user/arm/signal.c index 93c9bfc0d3..fb6228db6c 100644 --- a/bsd-user/arm/signal.c +++ b/bsd-user/arm/signal.c @@ -109,3 +109,79 @@ abi_long get_mcontext(CPUARMState *env, target_mcontext_t *mcp, int flags) } return err; } + +/* Compare to arm/arm/exec_machdep.c set_mcontext() */ +abi_long set_mcontext(CPUARMState *env, target_mcontext_t *mcp, int srflag) +{ + int err = 0; + const uint32_t *gr = mcp->__gregs; + uint32_t cpsr, ccpsr = cpsr_read(env); + uint32_t fpscr, mask; + + cpsr = tswap32(gr[TARGET_REG_CPSR]); + /* + * Only allow certain bits to change, reject attempted changes to non-user + * bits. In addition, make sure we're headed for user mode and none of the + * interrupt bits are set. + */ + if ((ccpsr & ~CPSR_USER) != (cpsr & ~CPSR_USER)) { + return -TARGET_EINVAL; + } + if ((cpsr & CPSR_M) != ARM_CPU_MODE_USR || + (cpsr & (CPSR_I | CPSR_F)) != 0) { + return -TARGET_EINVAL; + } + + /* + * The movs pc,lr instruction that implements the return to userland masks + * these bits out. + */ + mask = cpsr & CPSR_T ? 0x1 : 0x3; + + /* + * Make sure that we either have no vfp, or it's the correct size. + * FreeBSD just ignores it, though, so maybe we'll need to adjust + * things below instead. + */ + if (mcp->mc_vfp_size != 0 && mcp->mc_vfp_size != sizeof(target_mcontext_vfp_t)) { + return -TARGET_EINVAL; + } + + env->regs[0] = tswap32(gr[TARGET_REG_R0]); + env->regs[1] = tswap32(gr[TARGET_REG_R1]); + env->regs[2] = tswap32(gr[TARGET_REG_R2]); + env->regs[3] = tswap32(gr[TARGET_REG_R3]); + env->regs[4] = tswap32(gr[TARGET_REG_R4]); + env->regs[5] = tswap32(gr[TARGET_REG_R5]); + env->regs[6] = tswap32(gr[TARGET_REG_R6]); + env->regs[7] = tswap32(gr[TARGET_REG_R7]); + env->regs[8] = tswap32(gr[TARGET_REG_R8]); + env->regs[9] = tswap32(gr[TARGET_REG_R9]); + env->regs[10] = tswap32(gr[TARGET_REG_R10]); + env->regs[11] = tswap32(gr[TARGET_REG_R11]); + env->regs[12] = tswap32(gr[TARGET_REG_R12]); + + env->regs[13] = tswap32(gr[TARGET_REG_SP]); + env->regs[14] = tswap32(gr[TARGET_REG_LR]); + env->regs[15] = tswap32(gr[TARGET_REG_PC] & ~mask); + if (mcp->mc_vfp_size != 0 && mcp->mc_vfp_ptr != 0) { + /* see set_vfpcontext in sys/arm/arm/exec_machdep.c */ + target_mcontext_vfp_t *vfp; + + vfp = lock_user(VERIFY_READ, mcp->mc_vfp_ptr, sizeof(*vfp), 1); + for (int i = 0; i < 32; i++) { + __get_user(*aa32_vfp_dreg(env, i), &vfp->mcv_reg[i]); + } + __get_user(fpscr, &vfp->mcv_fpscr); + vfp_set_fpscr(env, fpscr); + unlock_user(vfp, mcp->mc_vfp_ptr, sizeof(target_ucontext_t)); + + /* + * linux-user sets fpexc, fpinst and fpinst2, but these aren't in + * FreeBSD's mcontext, what to do? + */ + } + cpsr_write(env, cpsr, CPSR_USER | CPSR_EXEC, CPSRWriteByInstr); + + return err; +}