xref: /linux/drivers/gpu/drm/xe/xe_ttm_vram_mgr.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2021-2022 Intel Corporation
4  * Copyright (C) 2021-2022 Red Hat
5  */
6 
7 #include <linux/cgroup_dmem.h>
8 
9 #include <drm/drm_managed.h>
10 #include <drm/drm_drv.h>
11 #include <drm/drm_buddy.h>
12 
13 #include <drm/ttm/ttm_placement.h>
14 #include <drm/ttm/ttm_range_manager.h>
15 
16 #include "xe_bo.h"
17 #include "xe_device.h"
18 #include "xe_pm.h"
19 #include "xe_res_cursor.h"
20 #include "xe_ttm_vram_mgr.h"
21 #include "xe_vram_types.h"
22 
23 static inline struct gpu_buddy_block *
24 xe_ttm_vram_mgr_first_block(struct list_head *list)
25 {
26 	return list_first_entry_or_null(list, struct gpu_buddy_block, link);
27 }
28 
29 static inline bool xe_is_vram_mgr_blocks_contiguous(struct gpu_buddy *mm,
30 						    struct list_head *head)
31 {
32 	struct gpu_buddy_block *block;
33 	u64 start, size;
34 
35 	block = xe_ttm_vram_mgr_first_block(head);
36 	if (!block)
37 		return false;
38 
39 	while (head != block->link.next) {
40 		start = gpu_buddy_block_offset(block);
41 		size = gpu_buddy_block_size(mm, block);
42 
43 		block = list_entry(block->link.next, struct gpu_buddy_block,
44 				   link);
45 		if (start + size != gpu_buddy_block_offset(block))
46 			return false;
47 	}
48 
49 	return true;
50 }
51 
52 static int xe_ttm_vram_mgr_new(struct ttm_resource_manager *man,
53 			       struct ttm_buffer_object *tbo,
54 			       const struct ttm_place *place,
55 			       struct ttm_resource **res)
56 {
57 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
58 	struct xe_ttm_vram_mgr_resource *vres;
59 	struct gpu_buddy *mm = &mgr->mm;
60 	u64 size, min_page_size;
61 	unsigned long lpfn;
62 	int err;
63 
64 	lpfn = place->lpfn;
65 	if (!lpfn || lpfn > man->size >> PAGE_SHIFT)
66 		lpfn = man->size >> PAGE_SHIFT;
67 
68 	if (tbo->base.size >> PAGE_SHIFT > (lpfn - place->fpfn))
69 		return -E2BIG; /* don't trigger eviction for the impossible */
70 
71 	vres = kzalloc_obj(*vres);
72 	if (!vres)
73 		return -ENOMEM;
74 
75 	ttm_resource_init(tbo, place, &vres->base);
76 
77 	/* bail out quickly if there's likely not enough VRAM for this BO */
78 	if (ttm_resource_manager_usage(man) > man->size) {
79 		err = -ENOSPC;
80 		goto error_fini;
81 	}
82 
83 	INIT_LIST_HEAD(&vres->blocks);
84 
85 	if (place->flags & TTM_PL_FLAG_TOPDOWN)
86 		vres->flags |= GPU_BUDDY_TOPDOWN_ALLOCATION;
87 
88 	if (place->flags & TTM_PL_FLAG_CONTIGUOUS)
89 		vres->flags |= GPU_BUDDY_CONTIGUOUS_ALLOCATION;
90 
91 	if (place->fpfn || lpfn != man->size >> PAGE_SHIFT)
92 		vres->flags |= GPU_BUDDY_RANGE_ALLOCATION;
93 
94 	if (WARN_ON(!vres->base.size)) {
95 		err = -EINVAL;
96 		goto error_fini;
97 	}
98 	size = vres->base.size;
99 
100 	min_page_size = mgr->default_page_size;
101 	if (tbo->page_alignment)
102 		min_page_size = (u64)tbo->page_alignment << PAGE_SHIFT;
103 
104 	if (WARN_ON(min_page_size < mm->chunk_size)) {
105 		err = -EINVAL;
106 		goto error_fini;
107 	}
108 
109 	if (WARN_ON(!IS_ALIGNED(size, min_page_size))) {
110 		err = -EINVAL;
111 		goto error_fini;
112 	}
113 
114 	mutex_lock(&mgr->lock);
115 	if (lpfn <= mgr->visible_size >> PAGE_SHIFT && size > mgr->visible_avail) {
116 		err = -ENOSPC;
117 		goto error_unlock;
118 	}
119 
120 	err = gpu_buddy_alloc_blocks(mm, (u64)place->fpfn << PAGE_SHIFT,
121 				     (u64)lpfn << PAGE_SHIFT, size,
122 				     min_page_size, &vres->blocks, vres->flags);
123 	if (err)
124 		goto error_unlock;
125 
126 	if (lpfn <= mgr->visible_size >> PAGE_SHIFT) {
127 		vres->used_visible_size = size;
128 	} else {
129 		struct gpu_buddy_block *block;
130 
131 		list_for_each_entry(block, &vres->blocks, link) {
132 			u64 start = gpu_buddy_block_offset(block);
133 
134 			if (start < mgr->visible_size) {
135 				u64 end = start + gpu_buddy_block_size(mm, block);
136 
137 				vres->used_visible_size +=
138 					min(end, mgr->visible_size) - start;
139 			}
140 		}
141 	}
142 
143 	mgr->visible_avail -= vres->used_visible_size;
144 	mutex_unlock(&mgr->lock);
145 
146 	if (!(vres->base.placement & TTM_PL_FLAG_CONTIGUOUS) &&
147 	    xe_is_vram_mgr_blocks_contiguous(mm, &vres->blocks))
148 		vres->base.placement |= TTM_PL_FLAG_CONTIGUOUS;
149 
150 	/*
151 	 * For some kernel objects we still rely on the start when io mapping
152 	 * the object.
153 	 */
154 	if (vres->base.placement & TTM_PL_FLAG_CONTIGUOUS) {
155 		struct gpu_buddy_block *block = list_first_entry(&vres->blocks,
156 								 typeof(*block),
157 								 link);
158 
159 		vres->base.start = gpu_buddy_block_offset(block) >> PAGE_SHIFT;
160 	} else {
161 		vres->base.start = XE_BO_INVALID_OFFSET;
162 	}
163 
164 	*res = &vres->base;
165 	return 0;
166 error_unlock:
167 	mutex_unlock(&mgr->lock);
168 error_fini:
169 	ttm_resource_fini(man, &vres->base);
170 	kfree(vres);
171 
172 	return err;
173 }
174 
175 static void xe_ttm_vram_mgr_del(struct ttm_resource_manager *man,
176 				struct ttm_resource *res)
177 {
178 	struct xe_ttm_vram_mgr_resource *vres =
179 		to_xe_ttm_vram_mgr_resource(res);
180 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
181 	struct gpu_buddy *mm = &mgr->mm;
182 
183 	mutex_lock(&mgr->lock);
184 	gpu_buddy_free_list(mm, &vres->blocks, 0);
185 	mgr->visible_avail += vres->used_visible_size;
186 	mutex_unlock(&mgr->lock);
187 
188 	ttm_resource_fini(man, res);
189 
190 	kfree(vres);
191 }
192 
193 static void xe_ttm_vram_mgr_debug(struct ttm_resource_manager *man,
194 				  struct drm_printer *printer)
195 {
196 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
197 	struct gpu_buddy *mm = &mgr->mm;
198 
199 	mutex_lock(&mgr->lock);
200 	drm_printf(printer, "default_page_size: %lluKiB\n",
201 		   mgr->default_page_size >> 10);
202 	drm_printf(printer, "visible_avail: %lluMiB\n",
203 		   (u64)mgr->visible_avail >> 20);
204 	drm_printf(printer, "visible_size: %lluMiB\n",
205 		   (u64)mgr->visible_size >> 20);
206 
207 	drm_buddy_print(mm, printer);
208 	mutex_unlock(&mgr->lock);
209 	drm_printf(printer, "man size:%llu\n", man->size);
210 }
211 
212 static bool xe_ttm_vram_mgr_intersects(struct ttm_resource_manager *man,
213 				       struct ttm_resource *res,
214 				       const struct ttm_place *place,
215 				       size_t size)
216 {
217 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
218 	struct xe_ttm_vram_mgr_resource *vres =
219 		to_xe_ttm_vram_mgr_resource(res);
220 	struct gpu_buddy *mm = &mgr->mm;
221 	struct gpu_buddy_block *block;
222 
223 	if (!place->fpfn && !place->lpfn)
224 		return true;
225 
226 	if (!place->fpfn && place->lpfn == mgr->visible_size >> PAGE_SHIFT)
227 		return vres->used_visible_size > 0;
228 
229 	list_for_each_entry(block, &vres->blocks, link) {
230 		unsigned long fpfn =
231 			gpu_buddy_block_offset(block) >> PAGE_SHIFT;
232 		unsigned long lpfn = fpfn +
233 			(gpu_buddy_block_size(mm, block) >> PAGE_SHIFT);
234 
235 		if (place->fpfn < lpfn && place->lpfn > fpfn)
236 			return true;
237 	}
238 
239 	return false;
240 }
241 
242 static bool xe_ttm_vram_mgr_compatible(struct ttm_resource_manager *man,
243 				       struct ttm_resource *res,
244 				       const struct ttm_place *place,
245 				       size_t size)
246 {
247 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
248 	struct xe_ttm_vram_mgr_resource *vres =
249 		to_xe_ttm_vram_mgr_resource(res);
250 	struct gpu_buddy *mm = &mgr->mm;
251 	struct gpu_buddy_block *block;
252 
253 	if (!place->fpfn && !place->lpfn)
254 		return true;
255 
256 	if (!place->fpfn && place->lpfn == mgr->visible_size >> PAGE_SHIFT)
257 		return vres->used_visible_size == size;
258 
259 	list_for_each_entry(block, &vres->blocks, link) {
260 		unsigned long fpfn =
261 			gpu_buddy_block_offset(block) >> PAGE_SHIFT;
262 		unsigned long lpfn = fpfn +
263 			(gpu_buddy_block_size(mm, block) >> PAGE_SHIFT);
264 
265 		if (fpfn < place->fpfn || lpfn > place->lpfn)
266 			return false;
267 	}
268 
269 	return true;
270 }
271 
272 static const struct ttm_resource_manager_func xe_ttm_vram_mgr_func = {
273 	.alloc	= xe_ttm_vram_mgr_new,
274 	.free	= xe_ttm_vram_mgr_del,
275 	.intersects = xe_ttm_vram_mgr_intersects,
276 	.compatible = xe_ttm_vram_mgr_compatible,
277 	.debug	= xe_ttm_vram_mgr_debug
278 };
279 
280 static const struct dmem_cgroup_ops xe_ttm_vram_mgr_dmem_ops;
281 
282 static int xe_ttm_vram_mgr_dmem_reclaim(struct dmem_cgroup_pool_state *pool,
283 					u64 target_bytes, void *priv)
284 {
285 	struct ttm_resource_manager *man = priv;
286 	struct xe_device *xe = ttm_to_xe_device(man->bdev);
287 	int ret, idx;
288 
289 	if (!drm_dev_enter(&xe->drm, &idx))
290 		return -ENODEV;
291 
292 	{
293 		ACQUIRE(xe_pm_runtime_ioctl, pm)(xe);
294 
295 		ret = ACQUIRE_ERR(xe_pm_runtime_ioctl, &pm);
296 		if (ret >= 0)
297 			ret = ttm_resource_manager_dmem_reclaim(pool, target_bytes, priv);
298 	}
299 
300 	drm_dev_exit(idx);
301 	return ret;
302 }
303 
304 static const struct dmem_cgroup_ops xe_ttm_vram_mgr_dmem_ops = {
305 	.reclaim = xe_ttm_vram_mgr_dmem_reclaim,
306 };
307 
308 static void xe_ttm_vram_mgr_set_unused(struct drm_device *dev, void *arg)
309 {
310 	struct ttm_resource_manager *man = arg;
311 
312 	ttm_resource_manager_set_used(man, false);
313 }
314 
315 static void xe_ttm_vram_mgr_fini(struct drm_device *dev, void *arg)
316 {
317 	struct xe_device *xe = to_xe_device(dev);
318 	struct xe_ttm_vram_mgr *mgr = arg;
319 	struct ttm_resource_manager *man = &mgr->manager;
320 
321 	if (ttm_resource_manager_evict_all(&xe->ttm, man))
322 		return;
323 
324 	WARN_ON_ONCE(mgr->visible_avail != mgr->visible_size);
325 
326 	gpu_buddy_fini(&mgr->mm);
327 
328 	ttm_resource_manager_cleanup(&mgr->manager);
329 
330 	ttm_set_driver_manager(&xe->ttm, mgr->mem_type, NULL);
331 }
332 
333 int __xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_ttm_vram_mgr *mgr,
334 			   u32 mem_type, u64 size, u64 io_size,
335 			   u64 default_page_size)
336 {
337 	struct ttm_resource_manager *man = &mgr->manager;
338 	struct dmem_cgroup_region *cg;
339 	const char *name;
340 	int err;
341 
342 	man->func = &xe_ttm_vram_mgr_func;
343 	mgr->mem_type = mem_type;
344 	err = drmm_mutex_init(&xe->drm, &mgr->lock);
345 	if (err)
346 		return err;
347 	mgr->default_page_size = default_page_size;
348 	mgr->visible_size = io_size;
349 	mgr->visible_avail = io_size;
350 
351 	ttm_resource_manager_init(man, &xe->ttm, size);
352 	err = gpu_buddy_init(&mgr->mm, man->size, default_page_size);
353 	if (err)
354 		return err;
355 
356 	gpu_buddy_driver_set_lock(&mgr->mm, &mgr->lock);
357 	ttm_set_driver_manager(&xe->ttm, mem_type, &mgr->manager);
358 
359 	/*
360 	 * Register the fini action before the cgroup region so that devres
361 	 * LIFO teardown runs unregister_region before manager teardown
362 	 * (draining any in-flight reclaim callbacks) and the manager fini second.
363 	 */
364 	err = drmm_add_action_or_reset(&xe->drm, xe_ttm_vram_mgr_fini, mgr);
365 	if (err)
366 		return err;
367 
368 	name = mem_type == XE_PL_VRAM0 ? "vram0" : "vram1";
369 	cg = drmm_cgroup_register_region(&xe->drm, name,
370 					 &(struct dmem_cgroup_init){
371 						.size = size,
372 						.ops = &xe_ttm_vram_mgr_dmem_ops,
373 						.reclaim_priv = man,
374 					 });
375 	if (IS_ERR(cg))
376 		return PTR_ERR(cg);
377 
378 	ttm_resource_manager_set_dmem_region(man, cg);
379 	ttm_resource_manager_set_used(man, true);
380 
381 	return drmm_add_action_or_reset(&xe->drm, xe_ttm_vram_mgr_set_unused, man);
382 }
383 
384 /**
385  * xe_ttm_vram_mgr_init - initialize TTM VRAM region
386  * @xe: pointer to Xe device
387  * @vram: pointer to xe_vram_region that contains the memory region attributes
388  *
389  * Initialize the Xe TTM for given @vram region using the given parameters.
390  *
391  * Returns 0 for success, negative error code otherwise.
392  */
393 int xe_ttm_vram_mgr_init(struct xe_device *xe, struct xe_vram_region *vram)
394 {
395 	return __xe_ttm_vram_mgr_init(xe, &vram->ttm, vram->placement,
396 				      xe_vram_region_usable_size(vram),
397 				      xe_vram_region_io_size(vram),
398 				      PAGE_SIZE);
399 }
400 
401 int xe_ttm_vram_mgr_alloc_sgt(struct xe_device *xe,
402 			      struct ttm_resource *res,
403 			      u64 offset, u64 length,
404 			      struct device *dev,
405 			      enum dma_data_direction dir,
406 			      struct sg_table **sgt)
407 {
408 	struct xe_tile *tile = &xe->tiles[res->mem_type - XE_PL_VRAM0];
409 	struct xe_ttm_vram_mgr_resource *vres = to_xe_ttm_vram_mgr_resource(res);
410 	struct xe_res_cursor cursor;
411 	struct scatterlist *sg;
412 	int num_entries = 0;
413 	int i, r;
414 
415 	if (vres->used_visible_size < res->size)
416 		return -EOPNOTSUPP;
417 
418 	*sgt = kmalloc_obj(**sgt);
419 	if (!*sgt)
420 		return -ENOMEM;
421 
422 	/* Determine the number of GPU_BUDDY blocks to export */
423 	xe_res_first(res, offset, length, &cursor);
424 	while (cursor.remaining) {
425 		num_entries++;
426 		/* Limit maximum size to 2GiB due to SG table limitations. */
427 		xe_res_next(&cursor, min_t(u64, cursor.size, SZ_2G));
428 	}
429 
430 	r = sg_alloc_table(*sgt, num_entries, GFP_KERNEL);
431 	if (r)
432 		goto error_free;
433 
434 	/* Initialize scatterlist nodes of sg_table */
435 	for_each_sgtable_sg((*sgt), sg, i)
436 		sg->length = 0;
437 
438 	/*
439 	 * Walk down GPU_BUDDY blocks to populate scatterlist nodes
440 	 * @note: Use iterator api to get first the GPU_BUDDY block
441 	 * and the number of bytes from it. Access the following
442 	 * GPU_BUDDY block(s) if more buffer needs to exported
443 	 */
444 	xe_res_first(res, offset, length, &cursor);
445 	for_each_sgtable_sg((*sgt), sg, i) {
446 		phys_addr_t phys = cursor.start + xe_vram_region_io_start(tile->mem.vram);
447 		size_t size = min_t(u64, cursor.size, SZ_2G);
448 		dma_addr_t addr;
449 
450 		addr = dma_map_resource(dev, phys, size, dir,
451 					DMA_ATTR_SKIP_CPU_SYNC);
452 		r = dma_mapping_error(dev, addr);
453 		if (r)
454 			goto error_unmap;
455 
456 		sg_set_page(sg, NULL, size, 0);
457 		sg_dma_address(sg) = addr;
458 		sg_dma_len(sg) = size;
459 
460 		xe_res_next(&cursor, size);
461 	}
462 
463 	return 0;
464 
465 error_unmap:
466 	for_each_sgtable_sg((*sgt), sg, i) {
467 		if (!sg->length)
468 			continue;
469 
470 		dma_unmap_resource(dev, sg->dma_address,
471 				   sg->length, dir,
472 				   DMA_ATTR_SKIP_CPU_SYNC);
473 	}
474 	sg_free_table(*sgt);
475 
476 error_free:
477 	kfree(*sgt);
478 	return r;
479 }
480 
481 void xe_ttm_vram_mgr_free_sgt(struct device *dev, enum dma_data_direction dir,
482 			      struct sg_table *sgt)
483 {
484 	struct scatterlist *sg;
485 	int i;
486 
487 	for_each_sgtable_sg(sgt, sg, i)
488 		dma_unmap_resource(dev, sg->dma_address,
489 				   sg->length, dir,
490 				   DMA_ATTR_SKIP_CPU_SYNC);
491 	sg_free_table(sgt);
492 	kfree(sgt);
493 }
494 
495 u64 xe_ttm_vram_get_cpu_visible_size(struct ttm_resource_manager *man)
496 {
497 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
498 
499 	return mgr->visible_size;
500 }
501 
502 void xe_ttm_vram_get_used(struct ttm_resource_manager *man,
503 			  u64 *used, u64 *used_visible)
504 {
505 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
506 
507 	mutex_lock(&mgr->lock);
508 	*used = mgr->mm.size - mgr->mm.avail;
509 	*used_visible = mgr->visible_size - mgr->visible_avail;
510 	mutex_unlock(&mgr->lock);
511 }
512 
513 u64 xe_ttm_vram_get_avail(struct ttm_resource_manager *man)
514 {
515 	struct xe_ttm_vram_mgr *mgr = to_xe_ttm_vram_mgr(man);
516 	u64 avail;
517 
518 	mutex_lock(&mgr->lock);
519 	avail =  mgr->mm.avail;
520 	mutex_unlock(&mgr->lock);
521 
522 	return avail;
523 }
524