kernel/vm/kstack.cpp

27 // Allocates and maps a kernel stack with one page of padding before and after the mapping.
31     LTRACEF("allocating %s stack\n", unsafe ? "unsafe" : "safe");
37     // Create a VMO for our stack
42         TRACEF("error allocating %s stack for thread\n",
46     const char* name = unsafe ? "unsafe-stack" : "safe-stack";
49     // create a vmar with enough padding for a page before and after the stack
70     LTRACEF("%s stack vmar at %#" PRIxPTR "\n",
86     LTRACEF("%s stack mapping at %#" PRIxPTR "\n",
89     // fault in all the pages so we dont demand fault in the stack
104 zx_status_t vm_allocate_kstack(kstack_t* stack) {
105     DEBUG_ASSERT(stack->base == 0);
106     DEBUG_ASSERT(stack->size == 0);
107     DEBUG_ASSERT(stack->top == 0);
108     DEBUG_ASSERT(stack->vmar == nullptr);
110     DEBUG_ASSERT(stack->unsafe_base == 0);
111     DEBUG_ASSERT(stack->unsafe_vmar == nullptr);
120     stack->size = mapping->size();
121     stack->base = mapping->base();
122     stack->top = mapping->base() + DEFAULT_STACK_SIZE;
125     stack->vmar = vmar.leak_ref();
130         vm_free_kstack(stack);
133     stack->size = mapping->size();
134     stack->unsafe_base = mapping->base();
137     stack->unsafe_vmar = vmar.leak_ref();
143 zx_status_t vm_free_kstack(kstack_t* stack) {
144     stack->base = 0;
145     stack->size = 0;
146     stack->top = 0;
148     if (stack->vmar != nullptr) {
150             fbl::internal::MakeRefPtrNoAdopt(static_cast<VmAddressRegion*>(stack->vmar));
155         stack->vmar = nullptr;
159     stack->unsafe_base = 0;
161     if (stack->unsafe_vmar != nullptr) {
163             fbl::internal::MakeRefPtrNoAdopt(static_cast<VmAddressRegion*>(stack->unsafe_vmar));
168         stack->unsafe_vmar = nullptr;