1 // SPDX-License-Identifier: MIT 2 /* 3 * Copyright © 2021 Intel Corporation 4 */ 5 6 #include "xe_sync.h" 7 8 #include <linux/dma-fence-array.h> 9 #include <linux/kthread.h> 10 #include <linux/sched/mm.h> 11 #include <linux/uaccess.h> 12 13 #include <drm/drm_print.h> 14 #include <drm/drm_syncobj.h> 15 #include <uapi/drm/xe_drm.h> 16 17 #include "xe_device.h" 18 #include "xe_exec_queue.h" 19 #include "xe_macros.h" 20 #include "xe_sched_job_types.h" 21 22 struct xe_user_fence { 23 struct xe_device *xe; 24 struct kref refcount; 25 struct dma_fence_cb cb; 26 struct work_struct worker; 27 struct mm_struct *mm; 28 u64 __user *addr; 29 u64 value; 30 int signalled; 31 }; 32 33 static void user_fence_destroy(struct kref *kref) 34 { 35 struct xe_user_fence *ufence = container_of(kref, struct xe_user_fence, 36 refcount); 37 38 mmdrop(ufence->mm); 39 kfree(ufence); 40 } 41 42 static void user_fence_get(struct xe_user_fence *ufence) 43 { 44 kref_get(&ufence->refcount); 45 } 46 47 static void user_fence_put(struct xe_user_fence *ufence) 48 { 49 kref_put(&ufence->refcount, user_fence_destroy); 50 } 51 52 static struct xe_user_fence *user_fence_create(struct xe_device *xe, u64 addr, 53 u64 value) 54 { 55 struct xe_user_fence *ufence; 56 u64 __user *ptr = u64_to_user_ptr(addr); 57 u64 __maybe_unused prefetch_val; 58 59 if (get_user(prefetch_val, ptr)) 60 return ERR_PTR(-EFAULT); 61 62 ufence = kzalloc(sizeof(*ufence), GFP_KERNEL); 63 if (!ufence) 64 return ERR_PTR(-ENOMEM); 65 66 ufence->xe = xe; 67 kref_init(&ufence->refcount); 68 ufence->addr = ptr; 69 ufence->value = value; 70 ufence->mm = current->mm; 71 mmgrab(ufence->mm); 72 73 return ufence; 74 } 75 76 static void user_fence_worker(struct work_struct *w) 77 { 78 struct xe_user_fence *ufence = container_of(w, struct xe_user_fence, worker); 79 80 WRITE_ONCE(ufence->signalled, 1); 81 if (mmget_not_zero(ufence->mm)) { 82 kthread_use_mm(ufence->mm); 83 if (copy_to_user(ufence->addr, &ufence->value, sizeof(ufence->value))) 84 XE_WARN_ON("Copy to user failed"); 85 kthread_unuse_mm(ufence->mm); 86 mmput(ufence->mm); 87 } else { 88 drm_dbg(&ufence->xe->drm, "mmget_not_zero() failed, ufence wasn't signaled\n"); 89 } 90 91 /* 92 * Wake up waiters only after updating the ufence state, allowing the UMD 93 * to safely reuse the same ufence without encountering -EBUSY errors. 94 */ 95 wake_up_all(&ufence->xe->ufence_wq); 96 user_fence_put(ufence); 97 } 98 99 static void kick_ufence(struct xe_user_fence *ufence, struct dma_fence *fence) 100 { 101 INIT_WORK(&ufence->worker, user_fence_worker); 102 queue_work(ufence->xe->ordered_wq, &ufence->worker); 103 dma_fence_put(fence); 104 } 105 106 static void user_fence_cb(struct dma_fence *fence, struct dma_fence_cb *cb) 107 { 108 struct xe_user_fence *ufence = container_of(cb, struct xe_user_fence, cb); 109 110 kick_ufence(ufence, fence); 111 } 112 113 int xe_sync_entry_parse(struct xe_device *xe, struct xe_file *xef, 114 struct xe_sync_entry *sync, 115 struct drm_xe_sync __user *sync_user, 116 struct drm_syncobj *ufence_syncobj, 117 u64 ufence_timeline_value, 118 unsigned int flags) 119 { 120 struct drm_xe_sync sync_in; 121 int err; 122 bool exec = flags & SYNC_PARSE_FLAG_EXEC; 123 bool in_lr_mode = flags & SYNC_PARSE_FLAG_LR_MODE; 124 bool disallow_user_fence = flags & SYNC_PARSE_FLAG_DISALLOW_USER_FENCE; 125 bool signal; 126 127 if (copy_from_user(&sync_in, sync_user, sizeof(*sync_user))) 128 return -EFAULT; 129 130 if (XE_IOCTL_DBG(xe, sync_in.flags & ~DRM_XE_SYNC_FLAG_SIGNAL) || 131 XE_IOCTL_DBG(xe, sync_in.reserved[0] || sync_in.reserved[1])) 132 return -EINVAL; 133 134 signal = sync_in.flags & DRM_XE_SYNC_FLAG_SIGNAL; 135 switch (sync_in.type) { 136 case DRM_XE_SYNC_TYPE_SYNCOBJ: 137 if (XE_IOCTL_DBG(xe, in_lr_mode && signal)) 138 return -EOPNOTSUPP; 139 140 if (XE_IOCTL_DBG(xe, upper_32_bits(sync_in.addr))) 141 return -EINVAL; 142 143 sync->syncobj = drm_syncobj_find(xef->drm, sync_in.handle); 144 if (XE_IOCTL_DBG(xe, !sync->syncobj)) 145 return -ENOENT; 146 147 if (!signal) { 148 sync->fence = drm_syncobj_fence_get(sync->syncobj); 149 if (XE_IOCTL_DBG(xe, !sync->fence)) 150 return -EINVAL; 151 } 152 break; 153 154 case DRM_XE_SYNC_TYPE_TIMELINE_SYNCOBJ: 155 if (XE_IOCTL_DBG(xe, in_lr_mode && signal)) 156 return -EOPNOTSUPP; 157 158 if (XE_IOCTL_DBG(xe, upper_32_bits(sync_in.addr))) 159 return -EINVAL; 160 161 if (XE_IOCTL_DBG(xe, sync_in.timeline_value == 0)) 162 return -EINVAL; 163 164 sync->syncobj = drm_syncobj_find(xef->drm, sync_in.handle); 165 if (XE_IOCTL_DBG(xe, !sync->syncobj)) 166 return -ENOENT; 167 168 if (signal) { 169 sync->chain_fence = dma_fence_chain_alloc(); 170 if (!sync->chain_fence) 171 return -ENOMEM; 172 } else { 173 sync->fence = drm_syncobj_fence_get(sync->syncobj); 174 if (XE_IOCTL_DBG(xe, !sync->fence)) 175 return -EINVAL; 176 177 err = dma_fence_chain_find_seqno(&sync->fence, 178 sync_in.timeline_value); 179 if (err) 180 return err; 181 } 182 break; 183 184 case DRM_XE_SYNC_TYPE_USER_FENCE: 185 if (XE_IOCTL_DBG(xe, disallow_user_fence)) 186 return -EOPNOTSUPP; 187 188 if (XE_IOCTL_DBG(xe, !signal)) 189 return -EOPNOTSUPP; 190 191 if (XE_IOCTL_DBG(xe, sync_in.addr & 0x7)) 192 return -EINVAL; 193 194 if (exec) { 195 sync->addr = sync_in.addr; 196 } else { 197 sync->ufence_timeline_value = ufence_timeline_value; 198 sync->ufence = user_fence_create(xe, sync_in.addr, 199 sync_in.timeline_value); 200 if (XE_IOCTL_DBG(xe, IS_ERR(sync->ufence))) 201 return PTR_ERR(sync->ufence); 202 sync->ufence_chain_fence = dma_fence_chain_alloc(); 203 if (!sync->ufence_chain_fence) 204 return -ENOMEM; 205 sync->ufence_syncobj = ufence_syncobj; 206 } 207 208 break; 209 210 default: 211 return -EINVAL; 212 } 213 214 sync->type = sync_in.type; 215 sync->flags = sync_in.flags; 216 sync->timeline_value = sync_in.timeline_value; 217 218 return 0; 219 } 220 ALLOW_ERROR_INJECTION(xe_sync_entry_parse, ERRNO); 221 222 int xe_sync_entry_add_deps(struct xe_sync_entry *sync, struct xe_sched_job *job) 223 { 224 if (sync->fence) 225 return drm_sched_job_add_dependency(&job->drm, 226 dma_fence_get(sync->fence)); 227 228 return 0; 229 } 230 231 /** 232 * xe_sync_entry_wait() - Wait on in-sync 233 * @sync: Sync object 234 * 235 * If the sync is in an in-sync, wait on the sync to signal. 236 * 237 * Return: 0 on success, -ERESTARTSYS on failure (interruption) 238 */ 239 int xe_sync_entry_wait(struct xe_sync_entry *sync) 240 { 241 return xe_sync_needs_wait(sync) ? 242 dma_fence_wait(sync->fence, true) : 0; 243 } 244 245 /** 246 * xe_sync_needs_wait() - Sync needs a wait (input dma-fence not signaled) 247 * @sync: Sync object 248 * 249 * Return: True if sync needs a wait, False otherwise 250 */ 251 bool xe_sync_needs_wait(struct xe_sync_entry *sync) 252 { 253 return sync->fence && 254 !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &sync->fence->flags); 255 } 256 257 void xe_sync_entry_signal(struct xe_sync_entry *sync, struct dma_fence *fence) 258 { 259 if (!(sync->flags & DRM_XE_SYNC_FLAG_SIGNAL)) 260 return; 261 262 if (sync->chain_fence) { 263 drm_syncobj_add_point(sync->syncobj, sync->chain_fence, 264 fence, sync->timeline_value); 265 /* 266 * The chain's ownership is transferred to the 267 * timeline. 268 */ 269 sync->chain_fence = NULL; 270 } else if (sync->syncobj) { 271 drm_syncobj_replace_fence(sync->syncobj, fence); 272 } else if (sync->ufence) { 273 int err; 274 275 drm_syncobj_add_point(sync->ufence_syncobj, 276 sync->ufence_chain_fence, 277 fence, sync->ufence_timeline_value); 278 sync->ufence_chain_fence = NULL; 279 280 fence = drm_syncobj_fence_get(sync->ufence_syncobj); 281 user_fence_get(sync->ufence); 282 err = dma_fence_add_callback(fence, &sync->ufence->cb, 283 user_fence_cb); 284 if (err == -ENOENT) { 285 kick_ufence(sync->ufence, fence); 286 } else if (err) { 287 XE_WARN_ON("failed to add user fence"); 288 user_fence_put(sync->ufence); 289 dma_fence_put(fence); 290 } 291 } 292 } 293 294 void xe_sync_entry_cleanup(struct xe_sync_entry *sync) 295 { 296 if (sync->syncobj) 297 drm_syncobj_put(sync->syncobj); 298 dma_fence_put(sync->fence); 299 dma_fence_chain_free(sync->chain_fence); 300 dma_fence_chain_free(sync->ufence_chain_fence); 301 if (!IS_ERR_OR_NULL(sync->ufence)) 302 user_fence_put(sync->ufence); 303 } 304 305 /** 306 * xe_sync_in_fence_get() - Get a fence from syncs, exec queue, and VM 307 * @sync: input syncs 308 * @num_sync: number of syncs 309 * @q: exec queue 310 * @vm: VM 311 * 312 * Get a fence from syncs, exec queue, and VM. If syncs contain in-fences create 313 * and return a composite fence of all in-fences + last fence. If no in-fences 314 * return last fence on input exec queue. Caller must drop reference to 315 * returned fence. 316 * 317 * Return: fence on success, ERR_PTR(-ENOMEM) on failure 318 */ 319 struct dma_fence * 320 xe_sync_in_fence_get(struct xe_sync_entry *sync, int num_sync, 321 struct xe_exec_queue *q, struct xe_vm *vm) 322 { 323 struct dma_fence **fences = NULL; 324 struct dma_fence_array *cf = NULL; 325 struct dma_fence *fence; 326 int i, num_fence = 0, current_fence = 0; 327 328 lockdep_assert_held(&vm->lock); 329 330 /* Reject in fences */ 331 for (i = 0; i < num_sync; ++i) 332 if (sync[i].fence) 333 return ERR_PTR(-EOPNOTSUPP); 334 335 if (q->flags & EXEC_QUEUE_FLAG_VM) { 336 struct xe_exec_queue *__q; 337 struct xe_tile *tile; 338 u8 id; 339 340 for_each_tile(tile, vm->xe, id) { 341 num_fence++; 342 for_each_tlb_inval(i) 343 num_fence++; 344 } 345 346 fences = kmalloc_array(num_fence, sizeof(*fences), 347 GFP_KERNEL); 348 if (!fences) 349 return ERR_PTR(-ENOMEM); 350 351 fences[current_fence++] = 352 xe_exec_queue_last_fence_get(q, vm); 353 for_each_tlb_inval(i) 354 fences[current_fence++] = 355 xe_exec_queue_tlb_inval_last_fence_get(q, vm, i); 356 list_for_each_entry(__q, &q->multi_gt_list, 357 multi_gt_link) { 358 fences[current_fence++] = 359 xe_exec_queue_last_fence_get(__q, vm); 360 for_each_tlb_inval(i) 361 fences[current_fence++] = 362 xe_exec_queue_tlb_inval_last_fence_get(__q, vm, i); 363 } 364 365 xe_assert(vm->xe, current_fence == num_fence); 366 cf = dma_fence_array_create(num_fence, fences, 367 dma_fence_context_alloc(1), 368 1, false); 369 if (!cf) 370 goto err_out; 371 372 return &cf->base; 373 } 374 375 fence = xe_exec_queue_last_fence_get(q, vm); 376 return fence; 377 378 err_out: 379 while (current_fence) 380 dma_fence_put(fences[--current_fence]); 381 kfree(fences); 382 383 return ERR_PTR(-ENOMEM); 384 } 385 386 /** 387 * __xe_sync_ufence_get() - Get user fence from user fence 388 * @ufence: input user fence 389 * 390 * Get a user fence reference from user fence 391 * 392 * Return: xe_user_fence pointer with reference 393 */ 394 struct xe_user_fence *__xe_sync_ufence_get(struct xe_user_fence *ufence) 395 { 396 user_fence_get(ufence); 397 398 return ufence; 399 } 400 401 /** 402 * xe_sync_ufence_get() - Get user fence from sync 403 * @sync: input sync 404 * 405 * Get a user fence reference from sync. 406 * 407 * Return: xe_user_fence pointer with reference 408 */ 409 struct xe_user_fence *xe_sync_ufence_get(struct xe_sync_entry *sync) 410 { 411 user_fence_get(sync->ufence); 412 413 return sync->ufence; 414 } 415 416 /** 417 * xe_sync_ufence_put() - Put user fence reference 418 * @ufence: user fence reference 419 * 420 */ 421 void xe_sync_ufence_put(struct xe_user_fence *ufence) 422 { 423 user_fence_put(ufence); 424 } 425 426 /** 427 * xe_sync_ufence_get_status() - Get user fence status 428 * @ufence: user fence 429 * 430 * Return: 1 if signalled, 0 not signalled, <0 on error 431 */ 432 int xe_sync_ufence_get_status(struct xe_user_fence *ufence) 433 { 434 return READ_ONCE(ufence->signalled); 435 } 436