LXR qemu/linux-user/include/host/s390/host-signal.h

   1/*
   2 * host-signal.h: signal info dependent on the host architecture
   3 *
   4 * Copyright (c) 2003-2005 Fabrice Bellard
   5 * Copyright (c) 2021 Linaro Limited
   6 *
   7 * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
   8 * See the COPYING file in the top-level directory.
   9 */
  10
  11#ifndef S390_HOST_SIGNAL_H
  12#define S390_HOST_SIGNAL_H
  13
  14/* The third argument to a SA_SIGINFO handler is ucontext_t. */
  15typedef ucontext_t host_sigcontext;
  16
  17static inline uintptr_t host_signal_pc(host_sigcontext *uc)
  18{
  19    return uc->uc_mcontext.psw.addr;
  20}
  21
  22static inline void host_signal_set_pc(host_sigcontext *uc, uintptr_t pc)
  23{
  24    uc->uc_mcontext.psw.addr = pc;
  25}
  26
  27static inline void *host_signal_mask(host_sigcontext *uc)
  28{
  29    return &uc->uc_sigmask;
  30}
  31
  32static inline bool host_signal_write(siginfo_t *info, host_sigcontext *uc)
  33{
  34    uint16_t *pinsn = (uint16_t *)host_signal_pc(uc);
  35
  36    /*
  37     * ??? On linux, the non-rt signal handler has 4 (!) arguments instead
  38     * of the normal 2 arguments.  The 4th argument contains the "Translation-
  39     * Exception Identification for DAT Exceptions" from the hardware (aka
  40     * "int_parm_long"), which does in fact contain the is_write value.
  41     * The rt signal handler, as far as I can tell, does not give this value
  42     * at all.  Not that we could get to it from here even if it were.
  43     * So fall back to parsing instructions.  Treat read-modify-write ones as
  44     * writes, which is not fully correct, but for tracking self-modifying code
  45     * this is better than treating them as reads.  Checking si_addr page flags
  46     * might be a viable improvement, albeit a racy one.
  47     */
  48    /* ??? This is not even close to complete.  */
  49    switch (pinsn[0] >> 8) {
  50    case 0x50: /* ST */
  51    case 0x42: /* STC */
  52    case 0x40: /* STH */
  53    case 0x44: /* EX */
  54    case 0xba: /* CS */
  55    case 0xbb: /* CDS */
  56        return true;
  57    case 0xc4: /* RIL format insns */
  58        switch (pinsn[0] & 0xf) {
  59        case 0xf: /* STRL */
  60        case 0xb: /* STGRL */
  61        case 0x7: /* STHRL */
  62            return true;
  63        }
  64        break;
  65    case 0xc6: /* RIL-b format insns */
  66        switch (pinsn[0] & 0xf) {
  67        case 0x0: /* EXRL */
  68            return true;
  69        }
  70        break;
  71    case 0xc8: /* SSF format insns */
  72        switch (pinsn[0] & 0xf) {
  73        case 0x2: /* CSST */
  74            return true;
  75        }
  76        break;
  77    case 0xe3: /* RXY format insns */
  78        switch (pinsn[2] & 0xff) {
  79        case 0x50: /* STY */
  80        case 0x24: /* STG */
  81        case 0x72: /* STCY */
  82        case 0x70: /* STHY */
  83        case 0x8e: /* STPQ */
  84        case 0x3f: /* STRVH */
  85        case 0x3e: /* STRV */
  86        case 0x2f: /* STRVG */
  87            return true;
  88        }
  89        break;
  90    case 0xeb: /* RSY format insns */
  91        switch (pinsn[2] & 0xff) {
  92        case 0x14: /* CSY */
  93        case 0x30: /* CSG */
  94        case 0x31: /* CDSY */
  95        case 0x3e: /* CDSG */
  96        case 0xe4: /* LANG */
  97        case 0xe6: /* LAOG */
  98        case 0xe7: /* LAXG */
  99        case 0xe8: /* LAAG */
 100        case 0xea: /* LAALG */
 101        case 0xf4: /* LAN */
 102        case 0xf6: /* LAO */
 103        case 0xf7: /* LAX */
 104        case 0xfa: /* LAAL */
 105        case 0xf8: /* LAA */
 106            return true;
 107        }
 108        break;
 109    }
 110    return false;
 111}
 112
 113#endif
 114