1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * VFIO PCI Intel Graphics support 4 * 5 * Copyright (C) 2016 Red Hat, Inc. All rights reserved. 6 * Author: Alex Williamson <alex.williamson@redhat.com> 7 * 8 * Register a device specific region through which to provide read-only 9 * access to the Intel IGD opregion. The register defining the opregion 10 * address is also virtualized to prevent user modification. 11 */ 12 13 #include <linux/io.h> 14 #include <linux/pci.h> 15 #include <linux/uaccess.h> 16 #include <linux/vfio.h> 17 18 #include "vfio_pci_private.h" 19 20 #define OPREGION_SIGNATURE "IntelGraphicsMem" 21 #define OPREGION_SIZE (8 * 1024) 22 #define OPREGION_PCI_ADDR 0xfc 23 24 static size_t vfio_pci_igd_rw(struct vfio_pci_device *vdev, char __user *buf, 25 size_t count, loff_t *ppos, bool iswrite) 26 { 27 unsigned int i = VFIO_PCI_OFFSET_TO_INDEX(*ppos) - VFIO_PCI_NUM_REGIONS; 28 void *base = vdev->region[i].data; 29 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 30 31 if (pos >= vdev->region[i].size || iswrite) 32 return -EINVAL; 33 34 count = min(count, (size_t)(vdev->region[i].size - pos)); 35 36 if (copy_to_user(buf, base + pos, count)) 37 return -EFAULT; 38 39 *ppos += count; 40 41 return count; 42 } 43 44 static void vfio_pci_igd_release(struct vfio_pci_device *vdev, 45 struct vfio_pci_region *region) 46 { 47 memunmap(region->data); 48 } 49 50 static const struct vfio_pci_regops vfio_pci_igd_regops = { 51 .rw = vfio_pci_igd_rw, 52 .release = vfio_pci_igd_release, 53 }; 54 55 static int vfio_pci_igd_opregion_init(struct vfio_pci_device *vdev) 56 { 57 __le32 *dwordp = (__le32 *)(vdev->vconfig + OPREGION_PCI_ADDR); 58 u32 addr, size; 59 void *base; 60 int ret; 61 62 ret = pci_read_config_dword(vdev->pdev, OPREGION_PCI_ADDR, &addr); 63 if (ret) 64 return ret; 65 66 if (!addr || !(~addr)) 67 return -ENODEV; 68 69 base = memremap(addr, OPREGION_SIZE, MEMREMAP_WB); 70 if (!base) 71 return -ENOMEM; 72 73 if (memcmp(base, OPREGION_SIGNATURE, 16)) { 74 memunmap(base); 75 return -EINVAL; 76 } 77 78 size = le32_to_cpu(*(__le32 *)(base + 16)); 79 if (!size) { 80 memunmap(base); 81 return -EINVAL; 82 } 83 84 size *= 1024; /* In KB */ 85 86 if (size != OPREGION_SIZE) { 87 memunmap(base); 88 base = memremap(addr, size, MEMREMAP_WB); 89 if (!base) 90 return -ENOMEM; 91 } 92 93 ret = vfio_pci_register_dev_region(vdev, 94 PCI_VENDOR_ID_INTEL | VFIO_REGION_TYPE_PCI_VENDOR_TYPE, 95 VFIO_REGION_SUBTYPE_INTEL_IGD_OPREGION, 96 &vfio_pci_igd_regops, size, VFIO_REGION_INFO_FLAG_READ, base); 97 if (ret) { 98 memunmap(base); 99 return ret; 100 } 101 102 /* Fill vconfig with the hw value and virtualize register */ 103 *dwordp = cpu_to_le32(addr); 104 memset(vdev->pci_config_map + OPREGION_PCI_ADDR, 105 PCI_CAP_ID_INVALID_VIRT, 4); 106 107 return ret; 108 } 109 110 static size_t vfio_pci_igd_cfg_rw(struct vfio_pci_device *vdev, 111 char __user *buf, size_t count, loff_t *ppos, 112 bool iswrite) 113 { 114 unsigned int i = VFIO_PCI_OFFSET_TO_INDEX(*ppos) - VFIO_PCI_NUM_REGIONS; 115 struct pci_dev *pdev = vdev->region[i].data; 116 loff_t pos = *ppos & VFIO_PCI_OFFSET_MASK; 117 size_t size; 118 int ret; 119 120 if (pos >= vdev->region[i].size || iswrite) 121 return -EINVAL; 122 123 size = count = min(count, (size_t)(vdev->region[i].size - pos)); 124 125 if ((pos & 1) && size) { 126 u8 val; 127 128 ret = pci_user_read_config_byte(pdev, pos, &val); 129 if (ret) 130 return pcibios_err_to_errno(ret); 131 132 if (copy_to_user(buf + count - size, &val, 1)) 133 return -EFAULT; 134 135 pos++; 136 size--; 137 } 138 139 if ((pos & 3) && size > 2) { 140 u16 val; 141 142 ret = pci_user_read_config_word(pdev, pos, &val); 143 if (ret) 144 return pcibios_err_to_errno(ret); 145 146 val = cpu_to_le16(val); 147 if (copy_to_user(buf + count - size, &val, 2)) 148 return -EFAULT; 149 150 pos += 2; 151 size -= 2; 152 } 153 154 while (size > 3) { 155 u32 val; 156 157 ret = pci_user_read_config_dword(pdev, pos, &val); 158 if (ret) 159 return pcibios_err_to_errno(ret); 160 161 val = cpu_to_le32(val); 162 if (copy_to_user(buf + count - size, &val, 4)) 163 return -EFAULT; 164 165 pos += 4; 166 size -= 4; 167 } 168 169 while (size >= 2) { 170 u16 val; 171 172 ret = pci_user_read_config_word(pdev, pos, &val); 173 if (ret) 174 return pcibios_err_to_errno(ret); 175 176 val = cpu_to_le16(val); 177 if (copy_to_user(buf + count - size, &val, 2)) 178 return -EFAULT; 179 180 pos += 2; 181 size -= 2; 182 } 183 184 while (size) { 185 u8 val; 186 187 ret = pci_user_read_config_byte(pdev, pos, &val); 188 if (ret) 189 return pcibios_err_to_errno(ret); 190 191 if (copy_to_user(buf + count - size, &val, 1)) 192 return -EFAULT; 193 194 pos++; 195 size--; 196 } 197 198 *ppos += count; 199 200 return count; 201 } 202 203 static void vfio_pci_igd_cfg_release(struct vfio_pci_device *vdev, 204 struct vfio_pci_region *region) 205 { 206 struct pci_dev *pdev = region->data; 207 208 pci_dev_put(pdev); 209 } 210 211 static const struct vfio_pci_regops vfio_pci_igd_cfg_regops = { 212 .rw = vfio_pci_igd_cfg_rw, 213 .release = vfio_pci_igd_cfg_release, 214 }; 215 216 static int vfio_pci_igd_cfg_init(struct vfio_pci_device *vdev) 217 { 218 struct pci_dev *host_bridge, *lpc_bridge; 219 int ret; 220 221 host_bridge = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0, 0)); 222 if (!host_bridge) 223 return -ENODEV; 224 225 if (host_bridge->vendor != PCI_VENDOR_ID_INTEL || 226 host_bridge->class != (PCI_CLASS_BRIDGE_HOST << 8)) { 227 pci_dev_put(host_bridge); 228 return -EINVAL; 229 } 230 231 ret = vfio_pci_register_dev_region(vdev, 232 PCI_VENDOR_ID_INTEL | VFIO_REGION_TYPE_PCI_VENDOR_TYPE, 233 VFIO_REGION_SUBTYPE_INTEL_IGD_HOST_CFG, 234 &vfio_pci_igd_cfg_regops, host_bridge->cfg_size, 235 VFIO_REGION_INFO_FLAG_READ, host_bridge); 236 if (ret) { 237 pci_dev_put(host_bridge); 238 return ret; 239 } 240 241 lpc_bridge = pci_get_domain_bus_and_slot(0, 0, PCI_DEVFN(0x1f, 0)); 242 if (!lpc_bridge) 243 return -ENODEV; 244 245 if (lpc_bridge->vendor != PCI_VENDOR_ID_INTEL || 246 lpc_bridge->class != (PCI_CLASS_BRIDGE_ISA << 8)) { 247 pci_dev_put(lpc_bridge); 248 return -EINVAL; 249 } 250 251 ret = vfio_pci_register_dev_region(vdev, 252 PCI_VENDOR_ID_INTEL | VFIO_REGION_TYPE_PCI_VENDOR_TYPE, 253 VFIO_REGION_SUBTYPE_INTEL_IGD_LPC_CFG, 254 &vfio_pci_igd_cfg_regops, lpc_bridge->cfg_size, 255 VFIO_REGION_INFO_FLAG_READ, lpc_bridge); 256 if (ret) { 257 pci_dev_put(lpc_bridge); 258 return ret; 259 } 260 261 return 0; 262 } 263 264 int vfio_pci_igd_init(struct vfio_pci_device *vdev) 265 { 266 int ret; 267 268 ret = vfio_pci_igd_opregion_init(vdev); 269 if (ret) 270 return ret; 271 272 ret = vfio_pci_igd_cfg_init(vdev); 273 if (ret) 274 return ret; 275 276 return 0; 277 } 278