1 #include "kvm/devices.h" 2 #include "kvm/pci.h" 3 #include "kvm/ioport.h" 4 #include "kvm/irq.h" 5 #include "kvm/util.h" 6 #include "kvm/kvm.h" 7 8 #include <linux/err.h> 9 #include <assert.h> 10 11 #define PCI_BAR_OFFSET(b) (offsetof(struct pci_device_header, bar[b])) 12 13 static union pci_config_address pci_config_address; 14 15 /* This is within our PCI gap - in an unused area. 16 * Note this is a PCI *bus address*, is used to assign BARs etc.! 17 * (That's why it can still 32bit even with 64bit guests-- 64bit 18 * PCI isn't currently supported.) 19 */ 20 static u32 io_space_blocks = KVM_PCI_MMIO_AREA; 21 22 /* 23 * BARs must be naturally aligned, so enforce this in the allocator. 24 */ 25 u32 pci_get_io_space_block(u32 size) 26 { 27 u32 block = ALIGN(io_space_blocks, size); 28 io_space_blocks = block + size; 29 return block; 30 } 31 32 void pci__assign_irq(struct device_header *dev_hdr) 33 { 34 struct pci_device_header *pci_hdr = dev_hdr->data; 35 36 /* 37 * PCI supports only INTA#,B#,C#,D# per device. 38 * 39 * A#,B#,C#,D# are allowed for multifunctional devices so stick 40 * with A# for our single function devices. 41 */ 42 pci_hdr->irq_pin = 1; 43 pci_hdr->irq_line = irq__alloc_line(); 44 } 45 46 static void *pci_config_address_ptr(u16 port) 47 { 48 unsigned long offset; 49 void *base; 50 51 offset = port - PCI_CONFIG_ADDRESS; 52 base = &pci_config_address; 53 54 return base + offset; 55 } 56 57 static bool pci_config_address_out(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size) 58 { 59 void *p = pci_config_address_ptr(port); 60 61 memcpy(p, data, size); 62 63 return true; 64 } 65 66 static bool pci_config_address_in(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size) 67 { 68 void *p = pci_config_address_ptr(port); 69 70 memcpy(data, p, size); 71 72 return true; 73 } 74 75 static struct ioport_operations pci_config_address_ops = { 76 .io_in = pci_config_address_in, 77 .io_out = pci_config_address_out, 78 }; 79 80 static bool pci_device_exists(u8 bus_number, u8 device_number, u8 function_number) 81 { 82 if (pci_config_address.bus_number != bus_number) 83 return false; 84 85 if (pci_config_address.function_number != function_number) 86 return false; 87 88 return !IS_ERR_OR_NULL(device__find_dev(DEVICE_BUS_PCI, device_number)); 89 } 90 91 static bool pci_config_data_out(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size) 92 { 93 /* 94 * If someone accesses PCI configuration space offsets that are not 95 * aligned to 4 bytes, it uses ioports to signify that. 96 */ 97 pci_config_address.reg_offset = port - PCI_CONFIG_DATA; 98 99 pci__config_wr(vcpu->kvm, pci_config_address, data, size); 100 101 return true; 102 } 103 104 static bool pci_config_data_in(struct ioport *ioport, struct kvm_cpu *vcpu, u16 port, void *data, int size) 105 { 106 /* 107 * If someone accesses PCI configuration space offsets that are not 108 * aligned to 4 bytes, it uses ioports to signify that. 109 */ 110 pci_config_address.reg_offset = port - PCI_CONFIG_DATA; 111 112 pci__config_rd(vcpu->kvm, pci_config_address, data, size); 113 114 return true; 115 } 116 117 static struct ioport_operations pci_config_data_ops = { 118 .io_in = pci_config_data_in, 119 .io_out = pci_config_data_out, 120 }; 121 122 void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data, int size) 123 { 124 u8 dev_num; 125 126 dev_num = addr.device_number; 127 128 if (pci_device_exists(0, dev_num, 0)) { 129 unsigned long offset; 130 131 offset = addr.w & 0xff; 132 if (offset < sizeof(struct pci_device_header)) { 133 void *p = device__find_dev(DEVICE_BUS_PCI, dev_num)->data; 134 struct pci_device_header *hdr = p; 135 u8 bar = (offset - PCI_BAR_OFFSET(0)) / (sizeof(u32)); 136 u32 sz = PCI_IO_SIZE; 137 138 if (bar < 6 && hdr->bar_size[bar]) 139 sz = hdr->bar_size[bar]; 140 141 /* 142 * If the kernel masks the BAR it would expect to find the 143 * size of the BAR there next time it reads from it. 144 * When the kernel got the size it would write the address 145 * back. 146 */ 147 if (*(u32 *)(p + offset)) { 148 /* See if kernel tries to mask one of the BARs */ 149 if ((offset >= PCI_BAR_OFFSET(0)) && 150 (offset <= PCI_BAR_OFFSET(6)) && 151 (ioport__read32(data) == 0xFFFFFFFF)) 152 memcpy(p + offset, &sz, sizeof(sz)); 153 else 154 memcpy(p + offset, data, size); 155 } 156 } 157 } 158 } 159 160 void pci__config_rd(struct kvm *kvm, union pci_config_address addr, void *data, int size) 161 { 162 u8 dev_num; 163 164 dev_num = addr.device_number; 165 166 if (pci_device_exists(0, dev_num, 0)) { 167 unsigned long offset; 168 169 offset = addr.w & 0xff; 170 if (offset < sizeof(struct pci_device_header)) { 171 void *p = device__find_dev(DEVICE_BUS_PCI, dev_num)->data; 172 173 memcpy(data, p + offset, size); 174 } else { 175 memset(data, 0x00, size); 176 } 177 } else { 178 memset(data, 0xff, size); 179 } 180 } 181 182 static void pci_config_mmio_access(struct kvm_cpu *vcpu, u64 addr, u8 *data, 183 u32 len, u8 is_write, void *kvm) 184 { 185 union pci_config_address cfg_addr; 186 187 addr -= KVM_PCI_CFG_AREA; 188 cfg_addr.w = (u32)addr; 189 cfg_addr.enable_bit = 1; 190 191 if (is_write) 192 pci__config_wr(kvm, cfg_addr, data, len); 193 else 194 pci__config_rd(kvm, cfg_addr, data, len); 195 } 196 197 struct pci_device_header *pci__find_dev(u8 dev_num) 198 { 199 struct device_header *hdr = device__find_dev(DEVICE_BUS_PCI, dev_num); 200 201 if (IS_ERR_OR_NULL(hdr)) 202 return NULL; 203 204 return hdr->data; 205 } 206 207 int pci__init(struct kvm *kvm) 208 { 209 int r; 210 211 r = ioport__register(kvm, PCI_CONFIG_DATA + 0, &pci_config_data_ops, 4, NULL); 212 if (r < 0) 213 return r; 214 215 r = ioport__register(kvm, PCI_CONFIG_ADDRESS + 0, &pci_config_address_ops, 4, NULL); 216 if (r < 0) 217 goto err_unregister_data; 218 219 r = kvm__register_mmio(kvm, KVM_PCI_CFG_AREA, PCI_CFG_SIZE, false, 220 pci_config_mmio_access, kvm); 221 if (r < 0) 222 goto err_unregister_addr; 223 224 return 0; 225 226 err_unregister_addr: 227 ioport__unregister(kvm, PCI_CONFIG_ADDRESS); 228 err_unregister_data: 229 ioport__unregister(kvm, PCI_CONFIG_DATA); 230 return r; 231 } 232 dev_base_init(pci__init); 233 234 int pci__exit(struct kvm *kvm) 235 { 236 ioport__unregister(kvm, PCI_CONFIG_DATA); 237 ioport__unregister(kvm, PCI_CONFIG_ADDRESS); 238 239 return 0; 240 } 241 dev_base_exit(pci__exit); 242