Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 2 | /* Copyright (c) 2021-2022, NVIDIA CORPORATION & AFFILIATES |
| 3 | */ |
| 4 | #include <linux/file.h> |
| 5 | #include <linux/interval_tree.h> |
| 6 | #include <linux/iommu.h> |
| 7 | #include <linux/iommufd.h> |
| 8 | #include <linux/slab.h> |
| 9 | #include <linux/vfio.h> |
| 10 | #include <uapi/linux/vfio.h> |
| 11 | #include <uapi/linux/iommufd.h> |
| 12 | |
| 13 | #include "iommufd_private.h" |
| 14 | |
| 15 | static struct iommufd_ioas *get_compat_ioas(struct iommufd_ctx *ictx) |
| 16 | { |
| 17 | struct iommufd_ioas *ioas = ERR_PTR(-ENODEV); |
| 18 | |
| 19 | xa_lock(&ictx->objects); |
| 20 | if (!ictx->vfio_ioas || !iommufd_lock_obj(&ictx->vfio_ioas->obj)) |
| 21 | goto out_unlock; |
| 22 | ioas = ictx->vfio_ioas; |
| 23 | out_unlock: |
| 24 | xa_unlock(&ictx->objects); |
| 25 | return ioas; |
| 26 | } |
| 27 | |
| 28 | /** |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 29 | * iommufd_vfio_compat_ioas_get_id - Ensure a compat IOAS exists |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 30 | * @ictx: Context to operate on |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 31 | * @out_ioas_id: The IOAS ID of the compatibility IOAS |
| 32 | * |
| 33 | * Return the ID of the current compatibility IOAS. The ID can be passed into |
| 34 | * other functions that take an ioas_id. |
| 35 | */ |
| 36 | int iommufd_vfio_compat_ioas_get_id(struct iommufd_ctx *ictx, u32 *out_ioas_id) |
| 37 | { |
| 38 | struct iommufd_ioas *ioas; |
| 39 | |
| 40 | ioas = get_compat_ioas(ictx); |
| 41 | if (IS_ERR(ioas)) |
| 42 | return PTR_ERR(ioas); |
| 43 | *out_ioas_id = ioas->obj.id; |
| 44 | iommufd_put_object(&ioas->obj); |
| 45 | return 0; |
| 46 | } |
| 47 | EXPORT_SYMBOL_NS_GPL(iommufd_vfio_compat_ioas_get_id, IOMMUFD_VFIO); |
| 48 | |
| 49 | /** |
| 50 | * iommufd_vfio_compat_set_no_iommu - Called when a no-iommu device is attached |
| 51 | * @ictx: Context to operate on |
| 52 | * |
| 53 | * This allows selecting the VFIO_NOIOMMU_IOMMU and blocks normal types. |
| 54 | */ |
| 55 | int iommufd_vfio_compat_set_no_iommu(struct iommufd_ctx *ictx) |
| 56 | { |
| 57 | int ret; |
| 58 | |
| 59 | xa_lock(&ictx->objects); |
| 60 | if (!ictx->vfio_ioas) { |
| 61 | ictx->no_iommu_mode = 1; |
| 62 | ret = 0; |
| 63 | } else { |
| 64 | ret = -EINVAL; |
| 65 | } |
| 66 | xa_unlock(&ictx->objects); |
| 67 | return ret; |
| 68 | } |
| 69 | EXPORT_SYMBOL_NS_GPL(iommufd_vfio_compat_set_no_iommu, IOMMUFD_VFIO); |
| 70 | |
| 71 | /** |
| 72 | * iommufd_vfio_compat_ioas_create - Ensure the compat IOAS is created |
| 73 | * @ictx: Context to operate on |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 74 | * |
| 75 | * The compatibility IOAS is the IOAS that the vfio compatibility ioctls operate |
| 76 | * on since they do not have an IOAS ID input in their ABI. Only attaching a |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 77 | * group should cause a default creation of the internal ioas, this does nothing |
| 78 | * if an existing ioas has already been assigned somehow. |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 79 | */ |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 80 | int iommufd_vfio_compat_ioas_create(struct iommufd_ctx *ictx) |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 81 | { |
| 82 | struct iommufd_ioas *ioas = NULL; |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 83 | int ret; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 84 | |
| 85 | ioas = iommufd_ioas_alloc(ictx); |
| 86 | if (IS_ERR(ioas)) |
| 87 | return PTR_ERR(ioas); |
| 88 | |
| 89 | xa_lock(&ictx->objects); |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 90 | /* |
| 91 | * VFIO won't allow attaching a container to both iommu and no iommu |
| 92 | * operation |
| 93 | */ |
| 94 | if (ictx->no_iommu_mode) { |
| 95 | ret = -EINVAL; |
| 96 | goto out_abort; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 97 | } |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 98 | |
| 99 | if (ictx->vfio_ioas && iommufd_lock_obj(&ictx->vfio_ioas->obj)) { |
| 100 | ret = 0; |
| 101 | iommufd_put_object(&ictx->vfio_ioas->obj); |
| 102 | goto out_abort; |
| 103 | } |
| 104 | ictx->vfio_ioas = ioas; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 105 | xa_unlock(&ictx->objects); |
| 106 | |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 107 | /* |
| 108 | * An automatically created compat IOAS is treated as a userspace |
| 109 | * created object. Userspace can learn the ID via IOMMU_VFIO_IOAS_GET, |
| 110 | * and if not manually destroyed it will be destroyed automatically |
| 111 | * at iommufd release. |
| 112 | */ |
| 113 | iommufd_object_finalize(ictx, &ioas->obj); |
| 114 | return 0; |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 115 | |
| 116 | out_abort: |
| 117 | xa_unlock(&ictx->objects); |
| 118 | iommufd_object_abort(ictx, &ioas->obj); |
| 119 | return ret; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 120 | } |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 121 | EXPORT_SYMBOL_NS_GPL(iommufd_vfio_compat_ioas_create, IOMMUFD_VFIO); |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 122 | |
| 123 | int iommufd_vfio_ioas(struct iommufd_ucmd *ucmd) |
| 124 | { |
| 125 | struct iommu_vfio_ioas *cmd = ucmd->cmd; |
| 126 | struct iommufd_ioas *ioas; |
| 127 | |
| 128 | if (cmd->__reserved) |
| 129 | return -EOPNOTSUPP; |
| 130 | switch (cmd->op) { |
| 131 | case IOMMU_VFIO_IOAS_GET: |
| 132 | ioas = get_compat_ioas(ucmd->ictx); |
| 133 | if (IS_ERR(ioas)) |
| 134 | return PTR_ERR(ioas); |
| 135 | cmd->ioas_id = ioas->obj.id; |
| 136 | iommufd_put_object(&ioas->obj); |
| 137 | return iommufd_ucmd_respond(ucmd, sizeof(*cmd)); |
| 138 | |
| 139 | case IOMMU_VFIO_IOAS_SET: |
Yi Liu | 325de95 | 2023-03-27 02:33:46 -0700 | [diff] [blame] | 140 | ioas = iommufd_get_ioas(ucmd->ictx, cmd->ioas_id); |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 141 | if (IS_ERR(ioas)) |
| 142 | return PTR_ERR(ioas); |
| 143 | xa_lock(&ucmd->ictx->objects); |
| 144 | ucmd->ictx->vfio_ioas = ioas; |
| 145 | xa_unlock(&ucmd->ictx->objects); |
| 146 | iommufd_put_object(&ioas->obj); |
| 147 | return 0; |
| 148 | |
| 149 | case IOMMU_VFIO_IOAS_CLEAR: |
| 150 | xa_lock(&ucmd->ictx->objects); |
| 151 | ucmd->ictx->vfio_ioas = NULL; |
| 152 | xa_unlock(&ucmd->ictx->objects); |
| 153 | return 0; |
| 154 | default: |
| 155 | return -EOPNOTSUPP; |
| 156 | } |
| 157 | } |
| 158 | |
| 159 | static int iommufd_vfio_map_dma(struct iommufd_ctx *ictx, unsigned int cmd, |
| 160 | void __user *arg) |
| 161 | { |
| 162 | u32 supported_flags = VFIO_DMA_MAP_FLAG_READ | VFIO_DMA_MAP_FLAG_WRITE; |
| 163 | size_t minsz = offsetofend(struct vfio_iommu_type1_dma_map, size); |
| 164 | struct vfio_iommu_type1_dma_map map; |
| 165 | int iommu_prot = IOMMU_CACHE; |
| 166 | struct iommufd_ioas *ioas; |
| 167 | unsigned long iova; |
| 168 | int rc; |
| 169 | |
| 170 | if (copy_from_user(&map, arg, minsz)) |
| 171 | return -EFAULT; |
| 172 | |
| 173 | if (map.argsz < minsz || map.flags & ~supported_flags) |
| 174 | return -EINVAL; |
| 175 | |
| 176 | if (map.flags & VFIO_DMA_MAP_FLAG_READ) |
| 177 | iommu_prot |= IOMMU_READ; |
| 178 | if (map.flags & VFIO_DMA_MAP_FLAG_WRITE) |
| 179 | iommu_prot |= IOMMU_WRITE; |
| 180 | |
| 181 | ioas = get_compat_ioas(ictx); |
| 182 | if (IS_ERR(ioas)) |
| 183 | return PTR_ERR(ioas); |
| 184 | |
| 185 | /* |
| 186 | * Maps created through the legacy interface always use VFIO compatible |
| 187 | * rlimit accounting. If the user wishes to use the faster user based |
| 188 | * rlimit accounting then they must use the new interface. |
| 189 | */ |
| 190 | iova = map.iova; |
| 191 | rc = iopt_map_user_pages(ictx, &ioas->iopt, &iova, u64_to_user_ptr(map.vaddr), |
| 192 | map.size, iommu_prot, 0); |
| 193 | iommufd_put_object(&ioas->obj); |
| 194 | return rc; |
| 195 | } |
| 196 | |
| 197 | static int iommufd_vfio_unmap_dma(struct iommufd_ctx *ictx, unsigned int cmd, |
| 198 | void __user *arg) |
| 199 | { |
| 200 | size_t minsz = offsetofend(struct vfio_iommu_type1_dma_unmap, size); |
| 201 | /* |
| 202 | * VFIO_DMA_UNMAP_FLAG_GET_DIRTY_BITMAP is obsoleted by the new |
| 203 | * dirty tracking direction: |
| 204 | * https://lore.kernel.org/kvm/20220731125503.142683-1-yishaih@nvidia.com/ |
| 205 | * https://lore.kernel.org/kvm/20220428210933.3583-1-joao.m.martins@oracle.com/ |
| 206 | */ |
| 207 | u32 supported_flags = VFIO_DMA_UNMAP_FLAG_ALL; |
| 208 | struct vfio_iommu_type1_dma_unmap unmap; |
| 209 | unsigned long unmapped = 0; |
| 210 | struct iommufd_ioas *ioas; |
| 211 | int rc; |
| 212 | |
| 213 | if (copy_from_user(&unmap, arg, minsz)) |
| 214 | return -EFAULT; |
| 215 | |
| 216 | if (unmap.argsz < minsz || unmap.flags & ~supported_flags) |
| 217 | return -EINVAL; |
| 218 | |
| 219 | ioas = get_compat_ioas(ictx); |
| 220 | if (IS_ERR(ioas)) |
| 221 | return PTR_ERR(ioas); |
| 222 | |
| 223 | if (unmap.flags & VFIO_DMA_UNMAP_FLAG_ALL) { |
| 224 | if (unmap.iova != 0 || unmap.size != 0) { |
| 225 | rc = -EINVAL; |
| 226 | goto err_put; |
| 227 | } |
| 228 | rc = iopt_unmap_all(&ioas->iopt, &unmapped); |
| 229 | } else { |
| 230 | if (READ_ONCE(ioas->iopt.disable_large_pages)) { |
| 231 | /* |
| 232 | * Create cuts at the start and last of the requested |
| 233 | * range. If the start IOVA is 0 then it doesn't need to |
| 234 | * be cut. |
| 235 | */ |
| 236 | unsigned long iovas[] = { unmap.iova + unmap.size - 1, |
| 237 | unmap.iova - 1 }; |
| 238 | |
| 239 | rc = iopt_cut_iova(&ioas->iopt, iovas, |
| 240 | unmap.iova ? 2 : 1); |
| 241 | if (rc) |
| 242 | goto err_put; |
| 243 | } |
| 244 | rc = iopt_unmap_iova(&ioas->iopt, unmap.iova, unmap.size, |
| 245 | &unmapped); |
| 246 | } |
| 247 | unmap.size = unmapped; |
| 248 | if (copy_to_user(arg, &unmap, minsz)) |
| 249 | rc = -EFAULT; |
| 250 | |
| 251 | err_put: |
| 252 | iommufd_put_object(&ioas->obj); |
| 253 | return rc; |
| 254 | } |
| 255 | |
| 256 | static int iommufd_vfio_cc_iommu(struct iommufd_ctx *ictx) |
| 257 | { |
Nicolin Chen | 89db316 | 2023-10-25 21:39:32 -0700 | [diff] [blame] | 258 | struct iommufd_hwpt_paging *hwpt_paging; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 259 | struct iommufd_ioas *ioas; |
| 260 | int rc = 1; |
| 261 | |
| 262 | ioas = get_compat_ioas(ictx); |
| 263 | if (IS_ERR(ioas)) |
| 264 | return PTR_ERR(ioas); |
| 265 | |
| 266 | mutex_lock(&ioas->mutex); |
Nicolin Chen | 89db316 | 2023-10-25 21:39:32 -0700 | [diff] [blame] | 267 | list_for_each_entry(hwpt_paging, &ioas->hwpt_list, hwpt_item) { |
| 268 | if (!hwpt_paging->enforce_cache_coherency) { |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 269 | rc = 0; |
| 270 | break; |
| 271 | } |
| 272 | } |
| 273 | mutex_unlock(&ioas->mutex); |
| 274 | |
| 275 | iommufd_put_object(&ioas->obj); |
| 276 | return rc; |
| 277 | } |
| 278 | |
| 279 | static int iommufd_vfio_check_extension(struct iommufd_ctx *ictx, |
| 280 | unsigned long type) |
| 281 | { |
| 282 | switch (type) { |
| 283 | case VFIO_TYPE1_IOMMU: |
| 284 | case VFIO_TYPE1v2_IOMMU: |
| 285 | case VFIO_UNMAP_ALL: |
| 286 | return 1; |
| 287 | |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 288 | case VFIO_NOIOMMU_IOMMU: |
| 289 | return IS_ENABLED(CONFIG_VFIO_NOIOMMU); |
| 290 | |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 291 | case VFIO_DMA_CC_IOMMU: |
| 292 | return iommufd_vfio_cc_iommu(ictx); |
| 293 | |
| 294 | /* |
| 295 | * This is obsolete, and to be removed from VFIO. It was an incomplete |
| 296 | * idea that got merged. |
| 297 | * https://lore.kernel.org/kvm/0-v1-0093c9b0e345+19-vfio_no_nesting_jgg@nvidia.com/ |
| 298 | */ |
| 299 | case VFIO_TYPE1_NESTING_IOMMU: |
| 300 | return 0; |
| 301 | |
| 302 | /* |
| 303 | * VFIO_DMA_MAP_FLAG_VADDR |
| 304 | * https://lore.kernel.org/kvm/1611939252-7240-1-git-send-email-steven.sistare@oracle.com/ |
| 305 | * https://lore.kernel.org/all/Yz777bJZjTyLrHEQ@nvidia.com/ |
| 306 | * |
| 307 | * It is hard to see how this could be implemented safely. |
| 308 | */ |
| 309 | case VFIO_UPDATE_VADDR: |
| 310 | default: |
| 311 | return 0; |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | static int iommufd_vfio_set_iommu(struct iommufd_ctx *ictx, unsigned long type) |
| 316 | { |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 317 | bool no_iommu_mode = READ_ONCE(ictx->no_iommu_mode); |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 318 | struct iommufd_ioas *ioas = NULL; |
| 319 | int rc = 0; |
| 320 | |
Jason Gunthorpe | c9a397c | 2023-01-18 13:50:28 -0400 | [diff] [blame] | 321 | /* |
| 322 | * Emulation for NOIOMMU is imperfect in that VFIO blocks almost all |
| 323 | * other ioctls. We let them keep working but they mostly fail since no |
| 324 | * IOAS should exist. |
| 325 | */ |
| 326 | if (IS_ENABLED(CONFIG_VFIO_NOIOMMU) && type == VFIO_NOIOMMU_IOMMU && |
| 327 | no_iommu_mode) { |
| 328 | if (!capable(CAP_SYS_RAWIO)) |
| 329 | return -EPERM; |
| 330 | return 0; |
| 331 | } |
| 332 | |
| 333 | if ((type != VFIO_TYPE1_IOMMU && type != VFIO_TYPE1v2_IOMMU) || |
| 334 | no_iommu_mode) |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 335 | return -EINVAL; |
| 336 | |
| 337 | /* VFIO fails the set_iommu if there is no group */ |
| 338 | ioas = get_compat_ioas(ictx); |
| 339 | if (IS_ERR(ioas)) |
| 340 | return PTR_ERR(ioas); |
| 341 | |
| 342 | /* |
| 343 | * The difference between TYPE1 and TYPE1v2 is the ability to unmap in |
| 344 | * the middle of mapped ranges. This is complicated by huge page support |
| 345 | * which creates single large IOPTEs that cannot be split by the iommu |
| 346 | * driver. TYPE1 is very old at this point and likely nothing uses it, |
| 347 | * however it is simple enough to emulate by simply disabling the |
| 348 | * problematic large IOPTEs. Then we can safely unmap within any range. |
| 349 | */ |
| 350 | if (type == VFIO_TYPE1_IOMMU) |
| 351 | rc = iopt_disable_large_pages(&ioas->iopt); |
| 352 | iommufd_put_object(&ioas->obj); |
| 353 | return rc; |
| 354 | } |
| 355 | |
| 356 | static unsigned long iommufd_get_pagesizes(struct iommufd_ioas *ioas) |
| 357 | { |
| 358 | struct io_pagetable *iopt = &ioas->iopt; |
| 359 | unsigned long pgsize_bitmap = ULONG_MAX; |
| 360 | struct iommu_domain *domain; |
| 361 | unsigned long index; |
| 362 | |
| 363 | down_read(&iopt->domains_rwsem); |
| 364 | xa_for_each(&iopt->domains, index, domain) |
| 365 | pgsize_bitmap &= domain->pgsize_bitmap; |
| 366 | |
| 367 | /* See vfio_update_pgsize_bitmap() */ |
| 368 | if (pgsize_bitmap & ~PAGE_MASK) { |
| 369 | pgsize_bitmap &= PAGE_MASK; |
| 370 | pgsize_bitmap |= PAGE_SIZE; |
| 371 | } |
| 372 | pgsize_bitmap = max(pgsize_bitmap, ioas->iopt.iova_alignment); |
| 373 | up_read(&iopt->domains_rwsem); |
| 374 | return pgsize_bitmap; |
| 375 | } |
| 376 | |
| 377 | static int iommufd_fill_cap_iova(struct iommufd_ioas *ioas, |
| 378 | struct vfio_info_cap_header __user *cur, |
| 379 | size_t avail) |
| 380 | { |
| 381 | struct vfio_iommu_type1_info_cap_iova_range __user *ucap_iovas = |
| 382 | container_of(cur, |
| 383 | struct vfio_iommu_type1_info_cap_iova_range __user, |
| 384 | header); |
| 385 | struct vfio_iommu_type1_info_cap_iova_range cap_iovas = { |
| 386 | .header = { |
| 387 | .id = VFIO_IOMMU_TYPE1_INFO_CAP_IOVA_RANGE, |
| 388 | .version = 1, |
| 389 | }, |
| 390 | }; |
| 391 | struct interval_tree_span_iter span; |
| 392 | |
| 393 | interval_tree_for_each_span(&span, &ioas->iopt.reserved_itree, 0, |
| 394 | ULONG_MAX) { |
| 395 | struct vfio_iova_range range; |
| 396 | |
| 397 | if (!span.is_hole) |
| 398 | continue; |
| 399 | range.start = span.start_hole; |
| 400 | range.end = span.last_hole; |
| 401 | if (avail >= struct_size(&cap_iovas, iova_ranges, |
| 402 | cap_iovas.nr_iovas + 1) && |
| 403 | copy_to_user(&ucap_iovas->iova_ranges[cap_iovas.nr_iovas], |
| 404 | &range, sizeof(range))) |
| 405 | return -EFAULT; |
| 406 | cap_iovas.nr_iovas++; |
| 407 | } |
| 408 | if (avail >= struct_size(&cap_iovas, iova_ranges, cap_iovas.nr_iovas) && |
| 409 | copy_to_user(ucap_iovas, &cap_iovas, sizeof(cap_iovas))) |
| 410 | return -EFAULT; |
| 411 | return struct_size(&cap_iovas, iova_ranges, cap_iovas.nr_iovas); |
| 412 | } |
| 413 | |
| 414 | static int iommufd_fill_cap_dma_avail(struct iommufd_ioas *ioas, |
| 415 | struct vfio_info_cap_header __user *cur, |
| 416 | size_t avail) |
| 417 | { |
| 418 | struct vfio_iommu_type1_info_dma_avail cap_dma = { |
| 419 | .header = { |
| 420 | .id = VFIO_IOMMU_TYPE1_INFO_DMA_AVAIL, |
| 421 | .version = 1, |
| 422 | }, |
| 423 | /* |
| 424 | * iommufd's limit is based on the cgroup's memory limit. |
| 425 | * Normally vfio would return U16_MAX here, and provide a module |
| 426 | * parameter to adjust it. Since S390 qemu userspace actually |
| 427 | * pays attention and needs a value bigger than U16_MAX return |
| 428 | * U32_MAX. |
| 429 | */ |
| 430 | .avail = U32_MAX, |
| 431 | }; |
| 432 | |
| 433 | if (avail >= sizeof(cap_dma) && |
| 434 | copy_to_user(cur, &cap_dma, sizeof(cap_dma))) |
| 435 | return -EFAULT; |
| 436 | return sizeof(cap_dma); |
| 437 | } |
| 438 | |
| 439 | static int iommufd_vfio_iommu_get_info(struct iommufd_ctx *ictx, |
| 440 | void __user *arg) |
| 441 | { |
| 442 | typedef int (*fill_cap_fn)(struct iommufd_ioas *ioas, |
| 443 | struct vfio_info_cap_header __user *cur, |
| 444 | size_t avail); |
| 445 | static const fill_cap_fn fill_fns[] = { |
| 446 | iommufd_fill_cap_dma_avail, |
| 447 | iommufd_fill_cap_iova, |
| 448 | }; |
| 449 | size_t minsz = offsetofend(struct vfio_iommu_type1_info, iova_pgsizes); |
| 450 | struct vfio_info_cap_header __user *last_cap = NULL; |
Jason Gunthorpe | b3551ea | 2023-02-13 10:32:21 -0400 | [diff] [blame] | 451 | struct vfio_iommu_type1_info info = {}; |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 452 | struct iommufd_ioas *ioas; |
| 453 | size_t total_cap_size; |
| 454 | int rc; |
| 455 | int i; |
| 456 | |
| 457 | if (copy_from_user(&info, arg, minsz)) |
| 458 | return -EFAULT; |
| 459 | |
| 460 | if (info.argsz < minsz) |
| 461 | return -EINVAL; |
| 462 | minsz = min_t(size_t, info.argsz, sizeof(info)); |
| 463 | |
| 464 | ioas = get_compat_ioas(ictx); |
| 465 | if (IS_ERR(ioas)) |
| 466 | return PTR_ERR(ioas); |
| 467 | |
| 468 | info.flags = VFIO_IOMMU_INFO_PGSIZES; |
| 469 | info.iova_pgsizes = iommufd_get_pagesizes(ioas); |
| 470 | info.cap_offset = 0; |
| 471 | |
| 472 | down_read(&ioas->iopt.iova_rwsem); |
| 473 | total_cap_size = sizeof(info); |
| 474 | for (i = 0; i != ARRAY_SIZE(fill_fns); i++) { |
| 475 | int cap_size; |
| 476 | |
| 477 | if (info.argsz > total_cap_size) |
| 478 | cap_size = fill_fns[i](ioas, arg + total_cap_size, |
| 479 | info.argsz - total_cap_size); |
| 480 | else |
| 481 | cap_size = fill_fns[i](ioas, NULL, 0); |
| 482 | if (cap_size < 0) { |
| 483 | rc = cap_size; |
| 484 | goto out_put; |
| 485 | } |
Stefan Hajnoczi | a881b49 | 2023-08-09 16:31:44 -0400 | [diff] [blame] | 486 | cap_size = ALIGN(cap_size, sizeof(u64)); |
| 487 | |
Jason Gunthorpe | d624d66 | 2022-11-29 16:29:38 -0400 | [diff] [blame] | 488 | if (last_cap && info.argsz >= total_cap_size && |
| 489 | put_user(total_cap_size, &last_cap->next)) { |
| 490 | rc = -EFAULT; |
| 491 | goto out_put; |
| 492 | } |
| 493 | last_cap = arg + total_cap_size; |
| 494 | total_cap_size += cap_size; |
| 495 | } |
| 496 | |
| 497 | /* |
| 498 | * If the user did not provide enough space then only some caps are |
| 499 | * returned and the argsz will be updated to the correct amount to get |
| 500 | * all caps. |
| 501 | */ |
| 502 | if (info.argsz >= total_cap_size) |
| 503 | info.cap_offset = sizeof(info); |
| 504 | info.argsz = total_cap_size; |
| 505 | info.flags |= VFIO_IOMMU_INFO_CAPS; |
| 506 | if (copy_to_user(arg, &info, minsz)) { |
| 507 | rc = -EFAULT; |
| 508 | goto out_put; |
| 509 | } |
| 510 | rc = 0; |
| 511 | |
| 512 | out_put: |
| 513 | up_read(&ioas->iopt.iova_rwsem); |
| 514 | iommufd_put_object(&ioas->obj); |
| 515 | return rc; |
| 516 | } |
| 517 | |
| 518 | int iommufd_vfio_ioctl(struct iommufd_ctx *ictx, unsigned int cmd, |
| 519 | unsigned long arg) |
| 520 | { |
| 521 | void __user *uarg = (void __user *)arg; |
| 522 | |
| 523 | switch (cmd) { |
| 524 | case VFIO_GET_API_VERSION: |
| 525 | return VFIO_API_VERSION; |
| 526 | case VFIO_SET_IOMMU: |
| 527 | return iommufd_vfio_set_iommu(ictx, arg); |
| 528 | case VFIO_CHECK_EXTENSION: |
| 529 | return iommufd_vfio_check_extension(ictx, arg); |
| 530 | case VFIO_IOMMU_GET_INFO: |
| 531 | return iommufd_vfio_iommu_get_info(ictx, uarg); |
| 532 | case VFIO_IOMMU_MAP_DMA: |
| 533 | return iommufd_vfio_map_dma(ictx, cmd, uarg); |
| 534 | case VFIO_IOMMU_UNMAP_DMA: |
| 535 | return iommufd_vfio_unmap_dma(ictx, cmd, uarg); |
| 536 | case VFIO_IOMMU_DIRTY_PAGES: |
| 537 | default: |
| 538 | return -ENOIOCTLCMD; |
| 539 | } |
| 540 | return -ENOIOCTLCMD; |
| 541 | } |