/*
* Resume the domain if no pending events. If there are pending events, like
* another vcpu in a BP, report it. Otherwise, continue, and wait till an
* event, like bp or user doing xm pause, occurs.
*
* Returns: vcpuid : if a vcpu hits a breakpoint or end of step
* -1 : either an error (msg printed on terminal), or non-bp
* event, like "xm pause domid", to enter debugger
*/
vcpuid_t
xg_resume_n_wait(int guest_bitness)
{
vcpuid_t vcpu;
XGTRC("E:\n");
assert(_domain_is_paused());
if ((vcpu=_vcpu_in_bp()) != -1) {
/* another vcpu in breakpoint. return it's id */
return vcpu;
}
XGTRC("unpausing domain\n");
if (_unpause_domain())
return -1;
/* now wait for domain to pause */
_wait_domain_pause();
/* check again if any vcpu in BP, or user thru "xm pause" */
vcpu = _vcpu_in_bp();
XGTRC("X:vcpu:%d\n", vcpu);
return vcpu;
}
/*
* Single step the given vcpu. This is achieved by pausing all but given vcpus,
* setting the TF flag, let the domain run and pause, unpause all vcpus, and
* clear TF flag on given vcpu.
* Returns: 0 success
*/
int
xg_step(vcpuid_t which_vcpu, int guest_bitness)
{
int rc;
XGTRC("E:vcpu:%d\n", (int)which_vcpu);
if (_allbutone_vcpu(XEN_DOMCTL_gdbsx_pausevcpu, which_vcpu))
return 1;
if ((rc=_change_TF(which_vcpu, guest_bitness, 1)))
return rc;
XGTRC("unpausing domain\n");
/* now unpause the domain so our vcpu can execute */
if (_unpause_domain())
return 1;
/* wait for our vcpu to finish step */
_wait_domain_pause();
_allbutone_vcpu(XEN_DOMCTL_gdbsx_unpausevcpu, which_vcpu);
rc = _change_TF(which_vcpu, guest_bitness, 0);
return rc;
}
/*
* Attach to the given domid for debugging.
* Returns: max vcpu id : Success
* -1 : Failure
*/
int
xg_attach(int domid, int guest_bitness)
{
XGTRC("E:domid:%d\n", domid);
_dom_id = domctl.domain = domid;
domctl.interface_version = XEN_DOMCTL_INTERFACE_VERSION;
if (mlock(&domctl, sizeof(domctl))) {
XGERR("Unable to pin domctl in memory. errno:%d\n", errno);
return -1;
}
if (_check_hyp(guest_bitness))
return -1;
if (_domctl_hcall(XEN_DOMCTL_pausedomain, NULL, 0)) {
XGERR("Unable to pause domain:%d\n", _dom_id);
return -1;
}
memset(&domctl.u, 0, sizeof(domctl.u));
domctl.u.setdebugging.enable = 1;
if (_domctl_hcall(XEN_DOMCTL_setdebugging, NULL, 0)) {
XGERR("Unable to set domain to debug mode: errno:%d\n", errno);
_unpause_domain();
return -1;
}
memset(&domctl.u, 0, sizeof(domctl.u));
if (_domctl_hcall(XEN_DOMCTL_getdomaininfo, NULL, 0)) {
XGERR("Unable to get domain info: domid:%d errno:%d\n",
domid, errno);
_unpause_domain();
return -1;
}
if (!_domain_ok(&domctl.u.getdomaininfo)) {
_unpause_domain();
return -1;
}
_max_vcpu_id = domctl.u.getdomaininfo.max_vcpu_id;
_hvm_guest = (domctl.u.getdomaininfo.flags & XEN_DOMINF_hvm_guest);
_pvh_guest = (domctl.u.getdomaininfo.flags & XEN_DOMINF_pvh_guest);
return _max_vcpu_id;
}
/* Detach from guest for debugger exit */
void
xg_detach_deinit(void)
{
memset(&domctl.u, 0, sizeof(domctl.u));
domctl.u.setdebugging.enable = 0;
if (_domctl_hcall(XEN_DOMCTL_setdebugging, NULL, 0)) {
XGERR("Unable to reset domain debug mode: errno:%d\n", errno);
}
if (_domain_is_paused())
_unpause_domain();
close(_dom0_fd);
}
