void
doNormalTransfer(tcb_t *sender, word_t *sendBuffer, endpoint_t *endpoint,
word_t badge, bool_t canGrant, tcb_t *receiver,
word_t *receiveBuffer, bool_t diminish)
{
unsigned int msgTransferred;
message_info_t tag;
exception_t status;
extra_caps_t caps;
tag = messageInfoFromWord(getRegister(sender, msgInfoRegister));
if (canGrant) {
status = lookupExtraCaps(sender, sendBuffer, tag);
caps = current_extra_caps;
if (unlikely(status != EXCEPTION_NONE)) {
caps.excaprefs[0] = NULL;
}
} else {
caps = current_extra_caps;
caps.excaprefs[0] = NULL;
}
msgTransferred = copyMRs(sender, sendBuffer, receiver, receiveBuffer,
message_info_get_msgLength(tag));
tag = transferCaps(tag, caps, endpoint, receiver, receiveBuffer, diminish);
tag = message_info_set_msgLength(tag, msgTransferred);
setRegister(receiver, msgInfoRegister, wordFromMessageInfo(tag));
setRegister(receiver, badgeRegister, badge);
}
bool_t
handleFaultReply(tcb_t *receiver, tcb_t *sender)
{
message_info_t tag;
word_t label;
fault_t fault;
unsigned int length;
/* These lookups are moved inward from doReplyTransfer */
tag = messageInfoFromWord(getRegister(sender, msgInfoRegister));
label = message_info_get_msgLabel(tag);
length = message_info_get_msgLength(tag);
fault = receiver->tcbFault;
switch (fault_get_faultType(fault)) {
case fault_cap_fault:
return true;
case fault_vm_fault:
return true;
case fault_unknown_syscall: {
unsigned int i;
register_t r;
word_t v;
word_t *sendBuf;
sendBuf = lookupIPCBuffer(false, sender);
/* Assumes n_syscallMessage > n_msgRegisters */
for (i = 0; i < length && i < n_msgRegisters; i++) {
r = syscallMessage[i];
v = getRegister(sender, msgRegisters[i]);
setRegister(receiver, r, sanitiseRegister(r, v));
}
if (sendBuf) {
for (; i < length && i < n_syscallMessage; i++) {
r = syscallMessage[i];
v = sendBuf[i + 1];
setRegister(receiver, r, sanitiseRegister(r, v));
}
}
}
return (label == 0);
case fault_user_exception: {
unsigned int i;
register_t r;
word_t v;
/* Assumes n_exceptionMessage <= n_msgRegisters */
for (i = 0; i < length && i < n_exceptionMessage; i++) {
r = exceptionMessage[i];
v = getRegister(sender, msgRegisters[i]);
setRegister(receiver, r, sanitiseRegister(r, v));
}
}
return (label == 0);
default:
fail("Invalid fault");
}
}
static exception_t
handleInvocation(bool_t isCall, bool_t isBlocking)
{
seL4_MessageInfo_t info;
cptr_t cptr;
lookupCapAndSlot_ret_t lu_ret;
word_t *buffer;
exception_t status;
word_t length;
tcb_t *thread;
thread = ksCurThread;
info = messageInfoFromWord(getRegister(thread, msgInfoRegister));
cptr = getRegister(thread, capRegister);
/* faulting section */
lu_ret = lookupCapAndSlot(thread, cptr);
#if defined(DEBUG) || defined(CONFIG_BENCHMARK_TRACK_KERNEL_ENTRIES)
ksKernelEntry.cap_type = cap_get_capType(lu_ret.cap);
ksKernelEntry.invocation_tag = seL4_MessageInfo_get_label(info);
ksKernelEntry.is_fastpath = false;
#endif
if (unlikely(lu_ret.status != EXCEPTION_NONE)) {
userError("Invocation of invalid cap #%lu.", cptr);
current_fault = fault_cap_fault_new(cptr, false);
if (isBlocking) {
handleFault(thread);
}
return EXCEPTION_NONE;
}
buffer = lookupIPCBuffer(false, thread);
status = lookupExtraCaps(thread, buffer, info);
if (unlikely(status != EXCEPTION_NONE)) {
userError("Lookup of extra caps failed.");
if (isBlocking) {
handleFault(thread);
}
return EXCEPTION_NONE;
}
/* Syscall error/Preemptible section */
length = seL4_MessageInfo_get_length(info);
if (unlikely(length > n_msgRegisters && !buffer)) {
length = n_msgRegisters;
}
status = decodeInvocation(seL4_MessageInfo_get_label(info), length,
cptr, lu_ret.slot, lu_ret.cap,
current_extra_caps, isBlocking, isCall,
buffer);
if (unlikely(status == EXCEPTION_PREEMPTED)) {
return status;
}
if (unlikely(status == EXCEPTION_SYSCALL_ERROR)) {
if (isCall) {
replyFromKernel_error(thread);
}
return EXCEPTION_NONE;
}
if (unlikely(
thread_state_get_tsType(thread->tcbState) == ThreadState_Restart)) {
if (isCall) {
replyFromKernel_success_empty(thread);
}
setThreadState(thread, ThreadState_Running);
}
return EXCEPTION_NONE;
}
static exception_t
handleInvocation(bool_t isCall, bool_t isBlocking)
{
message_info_t info;
cptr_t cptr;
lookupCapAndSlot_ret_t lu_ret;
word_t *buffer;
exception_t status;
word_t length;
tcb_t *thread;
thread = ksCurThread;
info = messageInfoFromWord(getRegister(thread, msgInfoRegister));
cptr = getRegister(thread, capRegister);
/* faulting section */
lu_ret = lookupCapAndSlot(thread, cptr);
if (unlikely(lu_ret.status != EXCEPTION_NONE)) {
userError("Invocation of invalid cap #%d.", (int)cptr);
current_fault = fault_cap_fault_new(cptr, false);
if (isBlocking) {
handleFault(thread);
}
return EXCEPTION_NONE;
}
buffer = lookupIPCBuffer(false, thread);
status = lookupExtraCaps(thread, buffer, info);
if (unlikely(status != EXCEPTION_NONE)) {
userError("Lookup of extra caps failed.");
if (isBlocking) {
handleFault(thread);
}
return EXCEPTION_NONE;
}
/* Syscall error/Preemptible section */
length = message_info_get_msgLength(info);
if (unlikely(length > n_msgRegisters && !buffer)) {
length = n_msgRegisters;
}
status = decodeInvocation(message_info_get_msgLabel(info), length,
cptr, lu_ret.slot, lu_ret.cap,
current_extra_caps, isBlocking, isCall,
buffer);
if (unlikely(status == EXCEPTION_PREEMPTED)) {
return status;
}
if (unlikely(status == EXCEPTION_SYSCALL_ERROR)) {
if (isCall) {
replyFromKernel_error(thread);
}
return EXCEPTION_NONE;
}
if (unlikely(
thread_state_get_tsType(thread->tcbState) == ThreadState_Restart)) {
if (isCall) {
replyFromKernel_success_empty(thread);
}
setThreadState(thread, ThreadState_Running);
}
return EXCEPTION_NONE;
}
bool_t handleFaultReply(tcb_t *receiver, tcb_t *sender)
{
/* These lookups are moved inward from doReplyTransfer */
seL4_MessageInfo_t tag = messageInfoFromWord(getRegister(sender, msgInfoRegister));
word_t label = seL4_MessageInfo_get_label(tag);
word_t length = seL4_MessageInfo_get_length(tag);
seL4_Fault_t fault = receiver->tcbFault;
switch (seL4_Fault_get_seL4_FaultType(fault)) {
case seL4_Fault_CapFault:
return true;
case seL4_Fault_UnknownSyscall:
copyMRsFaultReply(sender, receiver, MessageID_Syscall, MIN(length, n_syscallMessage));
return (label == 0);
case seL4_Fault_UserException:
copyMRsFaultReply(sender, receiver, MessageID_Exception, MIN(length, n_exceptionMessage));
return (label == 0);
#ifdef CONFIG_HARDWARE_DEBUG_API
case seL4_Fault_DebugException: {
word_t n_instrs;
if (seL4_Fault_DebugException_get_exceptionReason(fault) != seL4_SingleStep) {
/* Only single-step replies are required to set message registers.
*/
return (label == 0);
}
if (length < DEBUG_REPLY_N_EXPECTED_REGISTERS) {
/* A single-step reply doesn't mean much if it isn't composed of the bp
* number and number of instructions to skip. But even if both aren't
* set, we can still allow the thread to continue because replying
* should uniformly resume thread execution, based on the general seL4
* API model.
*
* If it was single-step, but no reply registers were set, just
* default to skipping 1 and continuing.
*
* On x86, bp_num actually doesn't matter for single-stepping
* because single-stepping doesn't use a hardware register -- it
* uses EFLAGS.TF.
*/
n_instrs = 1;
} else {
/* If the reply had all expected registers set, proceed as normal */
n_instrs = getRegister(sender, msgRegisters[0]);
}
syscall_error_t res;
res = Arch_decodeConfigureSingleStepping(receiver, 0, n_instrs, true);
if (res.type != seL4_NoError) {
return false;
};
configureSingleStepping(receiver, 0, n_instrs, true);
/* Replying will always resume the thread: the only variant behaviour
* is whether or not the thread will be resumed with stepping still
* enabled.
*/
return (label == 0);
}
#endif
default:
return Arch_handleFaultReply(receiver, sender, seL4_Fault_get_seL4_FaultType(fault));
}
}
