1 #include <geekos/svm.h>
2 #include <geekos/vmm.h>
4 #include <geekos/vmcb.h>
6 extern struct vmm_os_hooks * os_hooks;
8 extern uint_t cpuid_ecx(uint_t op);
9 extern uint_t cpuid_edx(uint_t op);
10 extern void Get_MSR(uint_t MSR, uint_t * high_byte, uint_t * low_byte);
11 extern void Set_MSR(uint_t MSR, uint_t high_byte, uint_t low_byte);
12 extern uint_t launch_svm(vmcb_t * vmcb_addr);
15 /* Checks machine SVM capability */
16 /* Implemented from: AMD Arch Manual 3, sect 15.4 */
17 int is_svm_capable() {
18 uint_t ret = cpuid_ecx(CPUID_FEATURE_IDS);
19 uint_t vm_cr_low = 0, vm_cr_high = 0;
22 if ((ret & CPUID_FEATURE_IDS_ecx_svm_avail) == 0) {
23 PrintDebug("SVM Not Available\n");
27 Get_MSR(SVM_VM_CR_MSR, &vm_cr_high, &vm_cr_low);
29 if ((vm_cr_low & SVM_VM_CR_MSR_svmdis) == 0) {
33 ret = cpuid_edx(CPUID_SVM_REV_AND_FEATURE_IDS);
35 if ((ret & CPUID_SVM_REV_AND_FEATURE_IDS_edx_svml) == 0) {
36 PrintDebug("SVM BIOS Disabled, not unlockable\n");
38 PrintDebug("SVM is locked with a key\n");
46 void Init_SVM(struct vmm_ctrl_ops * vmm_ops) {
51 // Enable SVM on the CPU
52 Get_MSR(EFER_MSR, &(msr.e_reg.high), &(msr.e_reg.low));
53 msr.e_reg.low |= EFER_MSR_svm_enable;
54 Set_MSR(EFER_MSR, 0, msr.e_reg.low);
56 PrintDebug("SVM Enabled\n");
59 // Setup the host state save area
60 host_state = os_hooks->Allocate_Pages(1);
63 msr.e_reg.low = (uint_t)host_state;
66 PrintDebug("Host State being saved at %x\n", (uint_t)host_state);
67 Set_MSR(SVM_VM_HSAVE_PA_MSR, msr.e_reg.high, msr.e_reg.low);
71 // Setup the SVM specific vmm operations
72 vmm_ops->init_guest = &init_svm_guest;
73 vmm_ops->start_guest = &start_svm_guest;
80 int init_svm_guest(struct guest_info *info) {
81 PrintDebug("Allocating VMCB\n");
82 info->vmm_data = (void*)Allocate_VMCB();
84 PrintDebug("Initializing VMCB (addr=%x)\n", info->vmm_data);
85 Init_VMCB((vmcb_t*)(info->vmm_data), *info);
91 // can we start a kernel thread here...
92 int start_svm_guest(struct guest_info *info) {
93 vmcb_ctrl_t * guest_ctrl = 0;
95 ulong_t exit_code = 0;
97 PrintDebug("Launching SVM VM (vmcb=%x)\n", info->vmm_data);
99 launch_svm((vmcb_t*)(info->vmm_data));
101 guest_ctrl = GET_VMCB_CTRL_AREA((vmcb_t*)(info->vmm_data));
104 PrintDebug("SVM Returned: (Exit Code=%x) (VMCB=%x)\n",&(guest_ctrl->exit_code), info->vmm_data);
107 exit_code = guest_ctrl->exit_code;
109 PrintDebug("SVM Returned: Exit Code: %x\n",exit_code);
117 * We handle the svm exits here
118 * This function should probably be moved to another file to keep things managable....
120 int handle_svm_exit(struct VMM_GPRs guest_gprs) {
126 vmcb_t * Allocate_VMCB() {
127 vmcb_t * vmcb_page = (vmcb_t*)os_hooks->Allocate_Pages(1);
130 memset(vmcb_page, 0, 4096);
137 void Init_VMCB(vmcb_t *vmcb, guest_info_t vm_info) {
138 vmcb_ctrl_t * ctrl_area = GET_VMCB_CTRL_AREA(vmcb);
139 vmcb_saved_state_t * guest_state = GET_VMCB_SAVE_STATE_AREA(vmcb);
143 guest_state->rsp = vm_info.rsp;
144 guest_state->rip = vm_info.rip;
147 /* I pretty much just gutted this from TVMM */
148 /* Note: That means its probably wrong */
150 // set the segment registers to mirror ours
151 guest_state->cs.selector = 0;
152 guest_state->cs.attrib.fields.type = 0xa; // Code segment+read
153 guest_state->cs.attrib.fields.S = 1;
154 guest_state->cs.attrib.fields.P = 1;
155 guest_state->cs.attrib.fields.db = 1;
156 guest_state->cs.limit = 0xffffffff;
157 guest_state->cs.base = 0;
159 struct vmcb_selector *segregs [] = {&(guest_state->ss), &(guest_state->ds), &(guest_state->es), &(guest_state->fs), &(guest_state->gs), NULL};
160 for ( i = 0; segregs[i] != NULL; i++) {
161 struct vmcb_selector * seg = segregs[i];
164 seg->attrib.fields.type = 0x2; // Data Segment+read/write
165 seg->attrib.fields.S = 1;
166 seg->attrib.fields.P = 1;
167 seg->attrib.fields.db = 1;
168 seg->limit = 0xffffffff;
173 guest_state->efer |= EFER_MSR_svm_enable;
174 guest_state->cr0 = 0x00000001; // PE
175 guest_state->rflags = 0x00000002; // The reserved bit is always 1
176 ctrl_area->svm_instrs.instrs.VMRUN = 1;
177 ctrl_area->guest_ASID = 1;