Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


HVM capability enhancement: asynchronous upcalls to ROS userspace
[palacios.git] / palacios / src / palacios / vmm_hvm.c
index 43a8672..43e7c33 100644 (file)
@@ -104,6 +104,7 @@ static int hvm_hcall_handler(struct guest_info * core , hcall_id_t hcall_id, voi
     uint64_t bitness = core->vm_regs.rbx;
     uint64_t a1 = core->vm_regs.rcx;
     uint64_t a2 = core->vm_regs.rdx;
+    uint64_t a3 = core->vm_regs.rsi;
     struct v3_vm_hvm *h = &core->vm_info->hvm_state;
 
 
@@ -155,11 +156,70 @@ static int hvm_hcall_handler(struct guest_info * core , hcall_id_t hcall_id, voi
            }
            break;
            
+       case 0x8: // replace HRT image
+           // a2 = gva of image
+           // a3 = size of image
+           PrintDebug(core->vm_info,core,"hvm: request replacement HRT image addr=0x%llx size=0x%llx\n",a2,a3);
+
+           if (h->hrt_image) { 
+               // delete old
+               V3_VFree(h->hrt_image);
+               h->hrt_image = 0;
+           }
+
+           h->hrt_image = V3_VMalloc(a3);
+
+           if (!(h->hrt_image)) {
+               PrintError(core->vm_info,core, "hvm: failed to allocate space for replacement image\n");
+               core->vm_regs.rax = -1;
+           } else {
+               if (v3_read_gva_memory(core, a2, a3, (uint8_t*) h->hrt_image)!=a3) { 
+                   PrintError(core->vm_info, core, "hvm: cannot read replacement image\n");
+                   core->vm_regs.rax = -1;
+               } else {
+                   h->hrt_image_size = a3; 
+                   core->vm_regs.rax = 0;
+               }
+           }
+
+           if (core->vm_regs.rax) { 
+               PrintError(core->vm_info,core,"hvm: Failed to replace HRT image\n");
+           } else {
+               PrintDebug(core->vm_info,core,"hvm: HRT image successfully replaced\n");
+           }
+
+           break;
+
        case 0xf: // get HRT state
            core->vm_regs.rax = h->trans_state;
+           if (v3_write_gva_memory(core, a2, sizeof(h->ros_event), (uint8_t*) &h->ros_event)!=sizeof(h->ros_event)) { 
+               PrintError(core->vm_info, core, "hvm: cannot write back ROS event state to %p - continuing\n",(void*)a2);
+           }
            //PrintDebug(core->vm_info,core,"hvm: get HRT transaction state 0x%llx\n",core->vm_regs.rax);
            break;
 
+       case 0x10:
+           PrintDebug(core->vm_info, core, "hvm: ROS event request\n");
+           if (h->ros_event.event_type!=ROS_NONE) { 
+               PrintError(core->vm_info, core, "hvm: ROS event is already in progress\n");
+               core->vm_regs.rax = -1;
+           } else {
+               if (v3_read_gva_memory(core, a2, sizeof(h->ros_event), (uint8_t*)&h->ros_event)!=sizeof(h->ros_event)) { 
+                   PrintError(core->vm_info, core, "hvm: cannot read ROS event from %p\n",(void*)a2);
+                   core->vm_regs.rax = -1;
+               } else {
+                   core->vm_regs.rax = 0;
+               }
+           }
+
+           break;
+
+       case 0x1f:
+           PrintDebug(core->vm_info, core, "hvm: completion of ROS event (rc=0x%llx)\n",a2);
+           h->ros_event.event_type=ROS_NONE;
+           h->ros_event.last_ros_event_result = a2;
+           break;
+
        case 0x20: // invoke function (ROS->HRT)
        case 0x21: // invoke parallel function (ROS->HRT)
            if (v3_is_hvm_hrt_core(core)) { 
@@ -384,6 +444,40 @@ static int hvm_hcall_handler(struct guest_info * core , hcall_id_t hcall_id, voi
            }
                    
            break;
+           
+       case 0x40: // install or remove signal handler
+           if (v3_is_hvm_hrt_core(core)) { 
+               PrintError(core->vm_info,core, "hvm: HRT cannot install signal handler...\n");
+               core->vm_regs.rax=-1;
+           } else {
+               PrintDebug(core->vm_info,core,"hvm: install signal handler for CR3=%p, handler=%p, stack=%p\n",(void*)core->ctrl_regs.cr3, (void*)a2, (void*)a3);
+               if (h->ros_signal.code) { 
+                   PrintError(core->vm_info,core,"hvm: signal is pending...\n");
+                   core->vm_regs.rax=-1;
+               } else {
+                   if ((a2 || a3) && (h->ros_signal.handler || h->ros_signal.stack)) { 
+                       PrintError(core->vm_info,core,"hvm: attempt to replace existing handler without removing it first\n");
+                       core->vm_regs.rax=-1;
+                   } else {
+                       // actually make the change
+                       h->ros_signal.handler=a2;
+                       h->ros_signal.stack=a3;
+                       h->ros_signal.cr3=core->ctrl_regs.cr3;
+                       core->vm_regs.rax=0;
+
+                       // test by signalling back a hello 
+                       // if (a2 && a3) { 
+                       //    v3_hvm_signal_ros(core->vm_info,0xf00d);
+                       //}
+                   }
+               }
+           }
+           break;
+
+       case 0x41: // raise signal in the ROS from HRT or ROS
+           PrintDebug(core->vm_info,core,"hvm: HRT raises signal code=0x%llx\n", a2);
+           core->vm_regs.rax = v3_hvm_signal_ros(core->vm_info,a2);
+           break;
 
        default:
            PrintError(core->vm_info,core,"hvm: unknown hypercall %llx\n",a1);
@@ -495,6 +589,12 @@ int v3_deinit_hvm_vm(struct v3_vm_info *vm)
 {
     PrintDebug(vm, VCORE_NONE, "hvm: HVM VM deinit\n");
 
+    if (vm->hvm_state.hrt_image) { 
+       V3_VFree(vm->hvm_state.hrt_image);
+       vm->hvm_state.hrt_image=0;
+       vm->hvm_state.hrt_image_size=0;
+    }
+
     v3_remove_hypercall(vm,HVM_HCALL);
 
     if (vm->hvm_state.comm_page_hpa) { 
@@ -563,7 +663,7 @@ uint32_t v3_get_hvm_hrt_cores(struct v3_vm_info *vm)
 int v3_is_hvm_ros_mem_gpa(struct v3_vm_info *vm, addr_t gpa)
 {
     if (vm->hvm_state.is_hvm) { 
-       return gpa>=0 && gpa<vm->hvm_state.first_hrt_gpa;
+       return gpa<vm->hvm_state.first_hrt_gpa;
     } else {
        return 1;
     }
@@ -1321,21 +1421,26 @@ static int configure_hrt(struct v3_vm_info *vm, mb_data_t *mb)
 
 }
 
-static int setup_mb_kernel_hrt(struct v3_vm_info *vm)
+static int setup_mb_kernel_hrt(struct v3_vm_info *vm, void *data, uint64_t size)
 {
     mb_data_t mb;
 
-    if (v3_parse_multiboot_header(vm->hvm_state.hrt_file,&mb)) { 
+    if (v3_parse_multiboot_header(data, size, &mb)) { 
        PrintError(vm,VCORE_NONE, "hvm: failed to parse multiboot kernel header\n");
        return -1;
     }
 
+    if (!mb.mb64_hrt) { 
+       PrintError(vm,VCORE_NONE,"hvm: invalid HRT - there is no MB64_HRT tag\n");
+       return -1;
+    }
+
     if (configure_hrt(vm,&mb)) {
        PrintError(vm,VCORE_NONE, "hvm: cannot configure HRT\n");
        return -1;
     }
     
-    if (v3_write_multiboot_kernel(vm,&mb,vm->hvm_state.hrt_file,
+    if (v3_write_multiboot_kernel(vm,&mb,data,size,
                                  (void*)vm->hvm_state.first_hrt_gpa,
                                  vm->mem_size-vm->hvm_state.first_hrt_gpa)) {
        PrintError(vm,VCORE_NONE, "hvm: failed to write multiboot kernel into memory\n");
@@ -1357,11 +1462,23 @@ static int setup_mb_kernel_hrt(struct v3_vm_info *vm)
 
 static int setup_hrt(struct v3_vm_info *vm)
 {
-    if (is_elf(vm->hvm_state.hrt_file->data,vm->hvm_state.hrt_file->size) && 
-       find_mb_header(vm->hvm_state.hrt_file->data,vm->hvm_state.hrt_file->size)) { 
+    void *data;
+    uint64_t size;
+
+    // If the ROS has installed an image, it takes priority
+    if (vm->hvm_state.hrt_image) { 
+       data = vm->hvm_state.hrt_image;
+       size = vm->hvm_state.hrt_image_size;
+    } else {
+       data = vm->hvm_state.hrt_file->data;
+       size = vm->hvm_state.hrt_file->size;
+    }
+       
+    if (is_elf(data,size) &&
+       find_mb_header(data,size)) {
 
        PrintDebug(vm,VCORE_NONE,"hvm: appears to be a multiboot kernel\n");
-       if (setup_mb_kernel_hrt(vm)) { 
+       if (setup_mb_kernel_hrt(vm,data,size)) { 
            PrintError(vm,VCORE_NONE,"hvm: multiboot kernel setup failed\n");
            return -1;
        } 
@@ -1722,3 +1839,111 @@ int v3_handle_hvm_reset(struct guest_info *core)
        return 0;
     }
 }
+
+
+int v3_handle_hvm_entry(struct guest_info *core)
+{
+    if (!core->vm_info->hvm_state.is_hvm        // not relevant to non-HVM
+       || core->hvm_state.is_hrt              // not relevant to an HRT in an HVM
+       || !core->vm_info->hvm_state.ros_signal.code) { // not relevant if there is no code to inject
+
+       // Note that above check for code could race with a writer, but
+       // if that happens, we'll simply inject at the next opportunity instead of 
+       // this one (see below for atomic update)
+       return 0;
+    } else {
+       struct v3_ros_signal *s = &core->vm_info->hvm_state.ros_signal;
+
+       // HVM ROS
+       if (! (s->handler && // handler installed
+              s->cr3 &&     // process installed
+              s->stack &&   // stack installed
+              core->cpl == 3 &&  // user mode
+              core->ctrl_regs.cr3 == s->cr3) // right process active
+           ) {
+           // Cannot inject at this time
+           return 0;
+       } else {
+           // We can inject now, let's atomically see if we have something
+           // and commit to doing it if we do
+           uint64_t code;
+
+           // Get code, reset to allow next one
+           code = __sync_fetch_and_and(&(s->code), 0);
+
+           if (!code) { 
+               // nothing to do after all
+               return 0;
+           } else {
+
+               // actually do inject
+
+               uint64_t rsp;
+               uint64_t frame[6];
+               
+               PrintDebug(core->vm_info,core,"hvm: ROS interrupt starting with rip=%p rsp=%p\n", (void*) core->rip, (void*) core->vm_regs.rsp);
+               // build interrupt frame
+               frame[0] = code;
+               frame[1] = core->rip;
+               frame[2] = core->segments.cs.selector; // return cs
+               frame[3] = core->ctrl_regs.rflags;
+               frame[4] = core->vm_regs.rsp;
+               frame[5] = core->segments.ss.selector; // return ss
+               
+               rsp = (s->stack - 8) & (~0x7); // make sure we are aligned
+               rsp -= sizeof(frame);
+               
+
+               if (v3_write_gva_memory(core,(addr_t)rsp,sizeof(frame),(uint8_t*)frame)!=sizeof(frame)) { 
+                   PrintError(core->vm_info,core,"hvm: failed to write interrupt frame\n");
+                   // we just lost this inject
+                   return -1;
+               }
+               
+               // now make us look like we are jumping to the entry
+               core->rip = s->handler;
+               core->vm_regs.rsp = rsp;
+
+               PrintDebug(core->vm_info,core,"hvm: ROS frame is 0x%llx|0x%llx|0x%llx|0x%llx|0x%llx|0x%llx and and on entry rip=%p and rsp=%p\n", frame[0],frame[1],frame[2],frame[3],frame[4],frame[5],(void*) core->rip, (void*) core->vm_regs.rsp);
+               
+               // and we should be good to go
+               return 0;
+           } 
+       }
+    }
+}
+
+int v3_handle_hvm_exit(struct guest_info *core)
+{
+    // currently nothing
+    return 0;
+}
+
+int v3_hvm_signal_ros(struct v3_vm_info *vm, uint64_t code)
+{
+    struct v3_ros_signal *s = &vm->hvm_state.ros_signal;
+
+    if (!code) { 
+       PrintError(vm,VCORE_NONE,"hvm: cannot signal ros with code zero\n");
+       return -1;
+    }
+
+    // handler, etc, must exist
+    if (!s->handler || !s->stack) { 
+       PrintError(vm,VCORE_NONE,"hvm: cannot signal ros with no installed handler\n");
+       return -1;
+    } else {
+       // we set the code only if we are idle (code 0), 
+       // and we do so only 
+       if (!__sync_bool_compare_and_swap(&(s->code), 0, code)) {
+           PrintError(vm,VCORE_NONE,"hvm: signal was already asserted\n");
+           return -1;
+       } else {
+           PrintDebug(vm,VCORE_NONE,"hvm: raised signal 0x%llx to the ROS\n",code);
+           return 0;
+       }
+    }
+}
+
+
+