1 /* 2 * arm signal functions 3 * 4 * Copyright (c) 2013 Stacey D. Son 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, see <http://www.gnu.org/licenses/>. 18 */ 19 20 #include "qemu.h" 21 22 /* 23 * Compare to arm/arm/machdep.c sendsig() 24 * Assumes that target stack frame memory is locked. 25 */ 26 abi_long set_sigtramp_args(CPUARMState *env, int sig, 27 struct target_sigframe *frame, 28 abi_ulong frame_addr, 29 struct target_sigaction *ka) 30 { 31 /* 32 * Arguments to signal handler: 33 * r0 = signal number 34 * r1 = siginfo pointer 35 * r2 = ucontext pointer 36 * r5 = ucontext pointer 37 * pc = signal handler pointer 38 * sp = sigframe struct pointer 39 * lr = sigtramp at base of user stack 40 */ 41 42 env->regs[0] = sig; 43 env->regs[1] = frame_addr + 44 offsetof(struct target_sigframe, sf_si); 45 env->regs[2] = frame_addr + 46 offsetof(struct target_sigframe, sf_uc); 47 48 /* the trampoline uses r5 as the uc address */ 49 env->regs[5] = frame_addr + 50 offsetof(struct target_sigframe, sf_uc); 51 env->regs[TARGET_REG_PC] = ka->_sa_handler & ~1; 52 env->regs[TARGET_REG_SP] = frame_addr; 53 env->regs[TARGET_REG_LR] = TARGET_PS_STRINGS - TARGET_SZSIGCODE; 54 /* 55 * Low bit indicates whether or not we're entering thumb mode. 56 */ 57 cpsr_write(env, (ka->_sa_handler & 1) * CPSR_T, CPSR_T, CPSRWriteByInstr); 58 59 return 0; 60 } 61 62 static abi_long get_vfpcontext(CPUARMState *env, abi_ulong frame_addr, 63 struct target_sigframe *frame) 64 { 65 /* see sendsig and get_vfpcontext in sys/arm/arm/exec_machdep.c */ 66 target_mcontext_vfp_t *vfp = &frame->sf_vfp; 67 target_mcontext_t *mcp = &frame->sf_uc.uc_mcontext; 68 69 /* Assumes that mcp and vfp are locked */ 70 for (int i = 0; i < 32; i++) { 71 vfp->mcv_reg[i] = tswap64(*aa32_vfp_dreg(env, i)); 72 } 73 vfp->mcv_fpscr = tswap32(vfp_get_fpscr(env)); 74 mcp->mc_vfp_size = tswap32(sizeof(*vfp)); 75 mcp->mc_vfp_ptr = tswap32(frame_addr + ((uintptr_t)vfp - (uintptr_t)frame)); 76 return 0; 77 } 78 79 /* 80 * Compare to arm/arm/exec_machdep.c get_mcontext() 81 * Assumes that the memory is locked if mcp points to user memory. 82 */ 83 abi_long get_mcontext(CPUARMState *env, target_mcontext_t *mcp, int flags) 84 { 85 uint32_t *gr = mcp->__gregs; 86 87 gr[TARGET_REG_CPSR] = tswap32(cpsr_read(env)); 88 if (flags & TARGET_MC_GET_CLEAR_RET) { 89 gr[TARGET_REG_R0] = 0; 90 gr[TARGET_REG_CPSR] &= ~CPSR_C; 91 } else { 92 gr[TARGET_REG_R0] = tswap32(env->regs[0]); 93 } 94 95 gr[TARGET_REG_R1] = tswap32(env->regs[1]); 96 gr[TARGET_REG_R2] = tswap32(env->regs[2]); 97 gr[TARGET_REG_R3] = tswap32(env->regs[3]); 98 gr[TARGET_REG_R4] = tswap32(env->regs[4]); 99 gr[TARGET_REG_R5] = tswap32(env->regs[5]); 100 gr[TARGET_REG_R6] = tswap32(env->regs[6]); 101 gr[TARGET_REG_R7] = tswap32(env->regs[7]); 102 gr[TARGET_REG_R8] = tswap32(env->regs[8]); 103 gr[TARGET_REG_R9] = tswap32(env->regs[9]); 104 gr[TARGET_REG_R10] = tswap32(env->regs[10]); 105 gr[TARGET_REG_R11] = tswap32(env->regs[11]); 106 gr[TARGET_REG_R12] = tswap32(env->regs[12]); 107 108 gr[TARGET_REG_SP] = tswap32(env->regs[13]); 109 gr[TARGET_REG_LR] = tswap32(env->regs[14]); 110 gr[TARGET_REG_PC] = tswap32(env->regs[15]); 111 112 /* 113 * FreeBSD's get_mcontext doesn't save VFP info, but sets the pointer and 114 * size to zero. Applications that need the VFP state use 115 * sysarch(ARM_GET_VFPSTATE) and are expected to adjust mcontext after that. 116 */ 117 mcp->mc_vfp_size = 0; 118 mcp->mc_vfp_ptr = 0; 119 memset(&mcp->mc_spare, 0, sizeof(mcp->mc_spare)); 120 121 return 0; 122 } 123 124 /* 125 * Compare to arm/arm/exec_machdep.c sendsig() 126 * Assumes that the memory is locked if frame points to user memory. 127 */ 128 abi_long setup_sigframe_arch(CPUARMState *env, abi_ulong frame_addr, 129 struct target_sigframe *frame, int flags) 130 { 131 target_mcontext_t *mcp = &frame->sf_uc.uc_mcontext; 132 133 get_mcontext(env, mcp, flags); 134 get_vfpcontext(env, frame_addr, frame); 135 return 0; 136 } 137 138 /* Compare to arm/arm/exec_machdep.c set_mcontext() */ 139 abi_long set_mcontext(CPUARMState *env, target_mcontext_t *mcp, int srflag) 140 { 141 int err = 0; 142 const uint32_t *gr = mcp->__gregs; 143 uint32_t cpsr, ccpsr = cpsr_read(env); 144 uint32_t fpscr, mask; 145 146 cpsr = tswap32(gr[TARGET_REG_CPSR]); 147 /* 148 * Only allow certain bits to change, reject attempted changes to non-user 149 * bits. In addition, make sure we're headed for user mode and none of the 150 * interrupt bits are set. 151 */ 152 if ((ccpsr & ~CPSR_USER) != (cpsr & ~CPSR_USER)) { 153 return -TARGET_EINVAL; 154 } 155 if ((cpsr & CPSR_M) != ARM_CPU_MODE_USR || 156 (cpsr & (CPSR_I | CPSR_F)) != 0) { 157 return -TARGET_EINVAL; 158 } 159 160 /* 161 * The movs pc,lr instruction that implements the return to userland masks 162 * these bits out. 163 */ 164 mask = cpsr & CPSR_T ? 0x1 : 0x3; 165 166 /* 167 * Make sure that we either have no vfp, or it's the correct size. 168 * FreeBSD just ignores it, though, so maybe we'll need to adjust 169 * things below instead. 170 */ 171 if (mcp->mc_vfp_size != 0 && mcp->mc_vfp_size != sizeof(target_mcontext_vfp_t)) { 172 return -TARGET_EINVAL; 173 } 174 175 env->regs[0] = tswap32(gr[TARGET_REG_R0]); 176 env->regs[1] = tswap32(gr[TARGET_REG_R1]); 177 env->regs[2] = tswap32(gr[TARGET_REG_R2]); 178 env->regs[3] = tswap32(gr[TARGET_REG_R3]); 179 env->regs[4] = tswap32(gr[TARGET_REG_R4]); 180 env->regs[5] = tswap32(gr[TARGET_REG_R5]); 181 env->regs[6] = tswap32(gr[TARGET_REG_R6]); 182 env->regs[7] = tswap32(gr[TARGET_REG_R7]); 183 env->regs[8] = tswap32(gr[TARGET_REG_R8]); 184 env->regs[9] = tswap32(gr[TARGET_REG_R9]); 185 env->regs[10] = tswap32(gr[TARGET_REG_R10]); 186 env->regs[11] = tswap32(gr[TARGET_REG_R11]); 187 env->regs[12] = tswap32(gr[TARGET_REG_R12]); 188 189 env->regs[13] = tswap32(gr[TARGET_REG_SP]); 190 env->regs[14] = tswap32(gr[TARGET_REG_LR]); 191 env->regs[15] = tswap32(gr[TARGET_REG_PC] & ~mask); 192 if (mcp->mc_vfp_size != 0 && mcp->mc_vfp_ptr != 0) { 193 /* see set_vfpcontext in sys/arm/arm/exec_machdep.c */ 194 target_mcontext_vfp_t *vfp; 195 196 vfp = lock_user(VERIFY_READ, mcp->mc_vfp_ptr, sizeof(*vfp), 1); 197 for (int i = 0; i < 32; i++) { 198 __get_user(*aa32_vfp_dreg(env, i), &vfp->mcv_reg[i]); 199 } 200 __get_user(fpscr, &vfp->mcv_fpscr); 201 vfp_set_fpscr(env, fpscr); 202 unlock_user(vfp, mcp->mc_vfp_ptr, sizeof(target_ucontext_t)); 203 204 /* 205 * linux-user sets fpexc, fpinst and fpinst2, but these aren't in 206 * FreeBSD's mcontext, what to do? 207 */ 208 } 209 cpsr_write(env, cpsr, CPSR_USER | CPSR_EXEC, CPSRWriteByInstr); 210 211 return err; 212 } 213 214 /* Compare to arm/arm/machdep.c sys_sigreturn() */ 215 abi_long get_ucontext_sigreturn(CPUARMState *env, abi_ulong target_sf, 216 abi_ulong *target_uc) 217 { 218 *target_uc = target_sf; 219 220 return 0; 221 } 222