1 /* 2 * QEMU VMPort emulation 3 * 4 * Copyright (C) 2007 Hervé Poussineau 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 25 /* 26 * Guest code that interacts with this virtual device can be found 27 * in VMware open-vm-tools open-source project: 28 * https://github.com/vmware/open-vm-tools 29 */ 30 31 #include "qemu/osdep.h" 32 #include "hw/isa/isa.h" 33 #include "hw/qdev-properties.h" 34 #include "sysemu/hw_accel.h" 35 #include "qemu/log.h" 36 #include "vmport.h" 37 #include "cpu.h" 38 #include "trace.h" 39 40 #define VMPORT_CMD_GETVERSION 0x0a 41 #define VMPORT_CMD_GETRAMSIZE 0x14 42 43 #define VMPORT_ENTRIES 0x2c 44 #define VMPORT_MAGIC 0x564D5868 45 46 /* Compatibility flags for migration */ 47 #define VMPORT_COMPAT_READ_SET_EAX_BIT 0 48 #define VMPORT_COMPAT_READ_SET_EAX \ 49 (1 << VMPORT_COMPAT_READ_SET_EAX_BIT) 50 51 #define VMPORT(obj) OBJECT_CHECK(VMPortState, (obj), TYPE_VMPORT) 52 53 typedef struct VMPortState { 54 ISADevice parent_obj; 55 56 MemoryRegion io; 57 VMPortReadFunc *func[VMPORT_ENTRIES]; 58 void *opaque[VMPORT_ENTRIES]; 59 60 uint32_t compat_flags; 61 } VMPortState; 62 63 static VMPortState *port_state; 64 65 void vmport_register(unsigned char command, VMPortReadFunc *func, void *opaque) 66 { 67 if (command >= VMPORT_ENTRIES) { 68 return; 69 } 70 71 trace_vmport_register(command, func, opaque); 72 port_state->func[command] = func; 73 port_state->opaque[command] = opaque; 74 } 75 76 static uint64_t vmport_ioport_read(void *opaque, hwaddr addr, 77 unsigned size) 78 { 79 VMPortState *s = opaque; 80 CPUState *cs = current_cpu; 81 X86CPU *cpu = X86_CPU(cs); 82 CPUX86State *env = &cpu->env; 83 unsigned char command; 84 uint32_t eax; 85 86 cpu_synchronize_state(cs); 87 88 eax = env->regs[R_EAX]; 89 if (eax != VMPORT_MAGIC) { 90 goto out; 91 } 92 93 command = env->regs[R_ECX]; 94 trace_vmport_command(command); 95 if (command >= VMPORT_ENTRIES || !s->func[command]) { 96 qemu_log_mask(LOG_UNIMP, "vmport: unknown command %x\n", command); 97 goto out; 98 } 99 100 eax = s->func[command](s->opaque[command], addr); 101 102 out: 103 /* 104 * The call above to cpu_synchronize_state() gets vCPU registers values 105 * to QEMU but also cause QEMU to write QEMU vCPU registers values to 106 * vCPU implementation (e.g. Accelerator such as KVM) just before 107 * resuming guest. 108 * 109 * Therefore, in order to make IOPort return value propagate to 110 * guest EAX, we need to explicitly update QEMU EAX register value. 111 */ 112 if (s->compat_flags & VMPORT_COMPAT_READ_SET_EAX) { 113 cpu->env.regs[R_EAX] = eax; 114 } 115 116 return eax; 117 } 118 119 static void vmport_ioport_write(void *opaque, hwaddr addr, 120 uint64_t val, unsigned size) 121 { 122 X86CPU *cpu = X86_CPU(current_cpu); 123 124 cpu->env.regs[R_EAX] = vmport_ioport_read(opaque, addr, 4); 125 } 126 127 static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr) 128 { 129 X86CPU *cpu = X86_CPU(current_cpu); 130 131 cpu->env.regs[R_EBX] = VMPORT_MAGIC; 132 return 6; 133 } 134 135 static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr) 136 { 137 X86CPU *cpu = X86_CPU(current_cpu); 138 139 cpu->env.regs[R_EBX] = 0x1177; 140 return ram_size; 141 } 142 143 static const MemoryRegionOps vmport_ops = { 144 .read = vmport_ioport_read, 145 .write = vmport_ioport_write, 146 .impl = { 147 .min_access_size = 4, 148 .max_access_size = 4, 149 }, 150 .endianness = DEVICE_LITTLE_ENDIAN, 151 }; 152 153 static void vmport_realizefn(DeviceState *dev, Error **errp) 154 { 155 ISADevice *isadev = ISA_DEVICE(dev); 156 VMPortState *s = VMPORT(dev); 157 158 memory_region_init_io(&s->io, OBJECT(s), &vmport_ops, s, "vmport", 1); 159 isa_register_ioport(isadev, &s->io, 0x5658); 160 161 port_state = s; 162 /* Register some generic port commands */ 163 vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL); 164 vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL); 165 } 166 167 static Property vmport_properties[] = { 168 /* Used to enforce compatibility for migration */ 169 DEFINE_PROP_BIT("x-read-set-eax", VMPortState, compat_flags, 170 VMPORT_COMPAT_READ_SET_EAX_BIT, true), 171 DEFINE_PROP_END_OF_LIST(), 172 }; 173 174 static void vmport_class_initfn(ObjectClass *klass, void *data) 175 { 176 DeviceClass *dc = DEVICE_CLASS(klass); 177 178 dc->realize = vmport_realizefn; 179 /* Reason: realize sets global port_state */ 180 dc->user_creatable = false; 181 device_class_set_props(dc, vmport_properties); 182 } 183 184 static const TypeInfo vmport_info = { 185 .name = TYPE_VMPORT, 186 .parent = TYPE_ISA_DEVICE, 187 .instance_size = sizeof(VMPortState), 188 .class_init = vmport_class_initfn, 189 }; 190 191 static void vmport_register_types(void) 192 { 193 type_register_static(&vmport_info); 194 } 195 196 type_init(vmport_register_types) 197