xref: /openbmc/linux/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.h (revision 3999edf8ba0a2f404362269335030d5c35ca27b4)
1 /*
2  * Copyright 2016 Advanced Micro Devices, Inc.
3  *
4  * Permission is hereby granted, free of charge, to any person obtaining a
5  * copy of this software and associated documentation files (the "Software"),
6  * to deal in the Software without restriction, including without limitation
7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8  * and/or sell copies of the Software, and to permit persons to whom the
9  * Software is furnished to do so, subject to the following conditions:
10  *
11  * The above copyright notice and this permission notice shall be included in
12  * all copies or substantial portions of the Software.
13  *
14  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17  * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18  * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19  * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20  * OTHER DEALINGS IN THE SOFTWARE.
21  *
22  * Authors: Christian König
23  */
24 #ifndef __AMDGPU_VM_H__
25 #define __AMDGPU_VM_H__
26 
27 #include <linux/idr.h>
28 #include <linux/kfifo.h>
29 #include <linux/rbtree.h>
30 #include <drm/gpu_scheduler.h>
31 #include <drm/drm_file.h>
32 #include <drm/ttm/ttm_bo.h>
33 #include <linux/sched/mm.h>
34 
35 #include "amdgpu_sync.h"
36 #include "amdgpu_ring.h"
37 #include "amdgpu_ids.h"
38 
39 struct amdgpu_bo_va;
40 struct amdgpu_job;
41 struct amdgpu_bo_list_entry;
42 struct amdgpu_bo_vm;
43 struct amdgpu_mem_stats;
44 
45 /*
46  * GPUVM handling
47  */
48 
49 /* Maximum number of PTEs the hardware can write with one command */
50 #define AMDGPU_VM_MAX_UPDATE_SIZE	0x3FFFF
51 
52 /* number of entries in page table */
53 #define AMDGPU_VM_PTE_COUNT(adev) (1 << (adev)->vm_manager.block_size)
54 
55 #define AMDGPU_PTE_VALID	(1ULL << 0)
56 #define AMDGPU_PTE_SYSTEM	(1ULL << 1)
57 #define AMDGPU_PTE_SNOOPED	(1ULL << 2)
58 
59 /* RV+ */
60 #define AMDGPU_PTE_TMZ		(1ULL << 3)
61 
62 /* VI only */
63 #define AMDGPU_PTE_EXECUTABLE	(1ULL << 4)
64 
65 #define AMDGPU_PTE_READABLE	(1ULL << 5)
66 #define AMDGPU_PTE_WRITEABLE	(1ULL << 6)
67 
68 #define AMDGPU_PTE_FRAG(x)	((x & 0x1fULL) << 7)
69 
70 /* TILED for VEGA10, reserved for older ASICs  */
71 #define AMDGPU_PTE_PRT		(1ULL << 51)
72 
73 /* PDE is handled as PTE for VEGA10 */
74 #define AMDGPU_PDE_PTE		(1ULL << 54)
75 
76 #define AMDGPU_PTE_LOG          (1ULL << 55)
77 
78 /* PTE is handled as PDE for VEGA10 (Translate Further) */
79 #define AMDGPU_PTE_TF		(1ULL << 56)
80 
81 /* MALL noalloc for sienna_cichlid, reserved for older ASICs  */
82 #define AMDGPU_PTE_NOALLOC	(1ULL << 58)
83 
84 /* PDE Block Fragment Size for VEGA10 */
85 #define AMDGPU_PDE_BFS(a)	((uint64_t)a << 59)
86 
87 /* Flag combination to set no-retry with TF disabled */
88 #define AMDGPU_VM_NORETRY_FLAGS	(AMDGPU_PTE_EXECUTABLE | AMDGPU_PDE_PTE | \
89 				AMDGPU_PTE_TF)
90 
91 /* Flag combination to set no-retry with TF enabled */
92 #define AMDGPU_VM_NORETRY_FLAGS_TF (AMDGPU_PTE_VALID | AMDGPU_PTE_SYSTEM | \
93 				   AMDGPU_PTE_PRT)
94 /* For GFX9 */
95 #define AMDGPU_PTE_MTYPE_VG10(a)	((uint64_t)(a) << 57)
96 #define AMDGPU_PTE_MTYPE_VG10_MASK	AMDGPU_PTE_MTYPE_VG10(3ULL)
97 
98 #define AMDGPU_MTYPE_NC 0
99 #define AMDGPU_MTYPE_CC 2
100 
101 #define AMDGPU_PTE_DEFAULT_ATC  (AMDGPU_PTE_SYSTEM      \
102                                 | AMDGPU_PTE_SNOOPED    \
103                                 | AMDGPU_PTE_EXECUTABLE \
104                                 | AMDGPU_PTE_READABLE   \
105                                 | AMDGPU_PTE_WRITEABLE  \
106                                 | AMDGPU_PTE_MTYPE_VG10(AMDGPU_MTYPE_CC))
107 
108 /* gfx10 */
109 #define AMDGPU_PTE_MTYPE_NV10(a)       ((uint64_t)(a) << 48)
110 #define AMDGPU_PTE_MTYPE_NV10_MASK     AMDGPU_PTE_MTYPE_NV10(7ULL)
111 
112 /* How to program VM fault handling */
113 #define AMDGPU_VM_FAULT_STOP_NEVER	0
114 #define AMDGPU_VM_FAULT_STOP_FIRST	1
115 #define AMDGPU_VM_FAULT_STOP_ALWAYS	2
116 
117 /* Reserve 4MB VRAM for page tables */
118 #define AMDGPU_VM_RESERVED_VRAM		(8ULL << 20)
119 
120 /*
121  * max number of VMHUB
122  * layout: max 8 GFXHUB + 4 MMHUB0 + 1 MMHUB1
123  */
124 #define AMDGPU_MAX_VMHUBS			13
125 #define AMDGPU_GFXHUB(x)			(x)
126 #define AMDGPU_MMHUB0(x)			(8 + x)
127 #define AMDGPU_MMHUB1(x)			(8 + 4 + x)
128 
129 /* Reserve 2MB at top/bottom of address space for kernel use */
130 #define AMDGPU_VA_RESERVED_SIZE			(2ULL << 20)
131 
132 /* See vm_update_mode */
133 #define AMDGPU_VM_USE_CPU_FOR_GFX (1 << 0)
134 #define AMDGPU_VM_USE_CPU_FOR_COMPUTE (1 << 1)
135 
136 /* VMPT level enumerate, and the hiberachy is:
137  * PDB2->PDB1->PDB0->PTB
138  */
139 enum amdgpu_vm_level {
140 	AMDGPU_VM_PDB2,
141 	AMDGPU_VM_PDB1,
142 	AMDGPU_VM_PDB0,
143 	AMDGPU_VM_PTB
144 };
145 
146 /* base structure for tracking BO usage in a VM */
147 struct amdgpu_vm_bo_base {
148 	/* constant after initialization */
149 	struct amdgpu_vm		*vm;
150 	struct amdgpu_bo		*bo;
151 
152 	/* protected by bo being reserved */
153 	struct amdgpu_vm_bo_base	*next;
154 
155 	/* protected by spinlock */
156 	struct list_head		vm_status;
157 
158 	/* protected by the BO being reserved */
159 	bool				moved;
160 };
161 
162 /* provided by hw blocks that can write ptes, e.g., sdma */
163 struct amdgpu_vm_pte_funcs {
164 	/* number of dw to reserve per operation */
165 	unsigned	copy_pte_num_dw;
166 
167 	/* copy pte entries from GART */
168 	void (*copy_pte)(struct amdgpu_ib *ib,
169 			 uint64_t pe, uint64_t src,
170 			 unsigned count);
171 
172 	/* write pte one entry at a time with addr mapping */
173 	void (*write_pte)(struct amdgpu_ib *ib, uint64_t pe,
174 			  uint64_t value, unsigned count,
175 			  uint32_t incr);
176 	/* for linear pte/pde updates without addr mapping */
177 	void (*set_pte_pde)(struct amdgpu_ib *ib,
178 			    uint64_t pe,
179 			    uint64_t addr, unsigned count,
180 			    uint32_t incr, uint64_t flags);
181 };
182 
183 struct amdgpu_task_info {
184 	char	process_name[TASK_COMM_LEN];
185 	char	task_name[TASK_COMM_LEN];
186 	pid_t	pid;
187 	pid_t	tgid;
188 };
189 
190 /**
191  * struct amdgpu_vm_update_params
192  *
193  * Encapsulate some VM table update parameters to reduce
194  * the number of function parameters
195  *
196  */
197 struct amdgpu_vm_update_params {
198 
199 	/**
200 	 * @adev: amdgpu device we do this update for
201 	 */
202 	struct amdgpu_device *adev;
203 
204 	/**
205 	 * @vm: optional amdgpu_vm we do this update for
206 	 */
207 	struct amdgpu_vm *vm;
208 
209 	/**
210 	 * @immediate: if changes should be made immediately
211 	 */
212 	bool immediate;
213 
214 	/**
215 	 * @unlocked: true if the root BO is not locked
216 	 */
217 	bool unlocked;
218 
219 	/**
220 	 * @pages_addr:
221 	 *
222 	 * DMA addresses to use for mapping
223 	 */
224 	dma_addr_t *pages_addr;
225 
226 	/**
227 	 * @job: job to used for hw submission
228 	 */
229 	struct amdgpu_job *job;
230 
231 	/**
232 	 * @num_dw_left: number of dw left for the IB
233 	 */
234 	unsigned int num_dw_left;
235 
236 	/**
237 	 * @table_freed: return true if page table is freed when updating
238 	 */
239 	bool table_freed;
240 };
241 
242 struct amdgpu_vm_update_funcs {
243 	int (*map_table)(struct amdgpu_bo_vm *bo);
244 	int (*prepare)(struct amdgpu_vm_update_params *p, struct dma_resv *resv,
245 		       enum amdgpu_sync_mode sync_mode);
246 	int (*update)(struct amdgpu_vm_update_params *p,
247 		      struct amdgpu_bo_vm *bo, uint64_t pe, uint64_t addr,
248 		      unsigned count, uint32_t incr, uint64_t flags);
249 	int (*commit)(struct amdgpu_vm_update_params *p,
250 		      struct dma_fence **fence);
251 };
252 
253 struct amdgpu_vm {
254 	/* tree of virtual addresses mapped */
255 	struct rb_root_cached	va;
256 
257 	/* Lock to prevent eviction while we are updating page tables
258 	 * use vm_eviction_lock/unlock(vm)
259 	 */
260 	struct mutex		eviction_lock;
261 	bool			evicting;
262 	unsigned int		saved_flags;
263 
264 	/* Lock to protect vm_bo add/del/move on all lists of vm */
265 	spinlock_t		status_lock;
266 
267 	/* BOs who needs a validation */
268 	struct list_head	evicted;
269 
270 	/* PT BOs which relocated and their parent need an update */
271 	struct list_head	relocated;
272 
273 	/* per VM BOs moved, but not yet updated in the PT */
274 	struct list_head	moved;
275 
276 	/* All BOs of this VM not currently in the state machine */
277 	struct list_head	idle;
278 
279 	/* regular invalidated BOs, but not yet updated in the PT */
280 	struct list_head	invalidated;
281 
282 	/* BO mappings freed, but not yet updated in the PT */
283 	struct list_head	freed;
284 
285 	/* BOs which are invalidated, has been updated in the PTs */
286 	struct list_head        done;
287 
288 	/* PT BOs scheduled to free and fill with zero if vm_resv is not hold */
289 	struct list_head	pt_freed;
290 	struct work_struct	pt_free_work;
291 
292 	/* contains the page directory */
293 	struct amdgpu_vm_bo_base     root;
294 	struct dma_fence	*last_update;
295 
296 	/* Scheduler entities for page table updates */
297 	struct drm_sched_entity	immediate;
298 	struct drm_sched_entity	delayed;
299 
300 	/* Last finished delayed update */
301 	atomic64_t		tlb_seq;
302 	struct dma_fence	*last_tlb_flush;
303 
304 	/* How many times we had to re-generate the page tables */
305 	uint64_t		generation;
306 
307 	/* Last unlocked submission to the scheduler entities */
308 	struct dma_fence	*last_unlocked;
309 
310 	unsigned int		pasid;
311 	bool			reserved_vmid[AMDGPU_MAX_VMHUBS];
312 
313 	/* Flag to indicate if VM tables are updated by CPU or GPU (SDMA) */
314 	bool					use_cpu_for_update;
315 
316 	/* Functions to use for VM table updates */
317 	const struct amdgpu_vm_update_funcs	*update_funcs;
318 
319 	/* Flag to indicate ATS support from PTE for GFX9 */
320 	bool			pte_support_ats;
321 
322 	/* Up to 128 pending retry page faults */
323 	DECLARE_KFIFO(faults, u64, 128);
324 
325 	/* Points to the KFD process VM info */
326 	struct amdkfd_process_info *process_info;
327 
328 	/* List node in amdkfd_process_info.vm_list_head */
329 	struct list_head	vm_list_node;
330 
331 	/* Valid while the PD is reserved or fenced */
332 	uint64_t		pd_phys_addr;
333 
334 	/* Some basic info about the task */
335 	struct amdgpu_task_info task_info;
336 
337 	/* Store positions of group of BOs */
338 	struct ttm_lru_bulk_move lru_bulk_move;
339 	/* Flag to indicate if VM is used for compute */
340 	bool			is_compute_context;
341 
342 	/* Memory partition number, -1 means any partition */
343 	int8_t			mem_id;
344 };
345 
346 struct amdgpu_vm_manager {
347 	/* Handling of VMIDs */
348 	struct amdgpu_vmid_mgr			id_mgr[AMDGPU_MAX_VMHUBS];
349 	unsigned int				first_kfd_vmid;
350 	bool					concurrent_flush;
351 
352 	/* Handling of VM fences */
353 	u64					fence_context;
354 	unsigned				seqno[AMDGPU_MAX_RINGS];
355 
356 	uint64_t				max_pfn;
357 	uint32_t				num_level;
358 	uint32_t				block_size;
359 	uint32_t				fragment_size;
360 	enum amdgpu_vm_level			root_level;
361 	/* vram base address for page table entry  */
362 	u64					vram_base_offset;
363 	/* vm pte handling */
364 	const struct amdgpu_vm_pte_funcs	*vm_pte_funcs;
365 	struct drm_gpu_scheduler		*vm_pte_scheds[AMDGPU_MAX_RINGS];
366 	unsigned				vm_pte_num_scheds;
367 	struct amdgpu_ring			*page_fault;
368 
369 	/* partial resident texture handling */
370 	spinlock_t				prt_lock;
371 	atomic_t				num_prt_users;
372 
373 	/* controls how VM page tables are updated for Graphics and Compute.
374 	 * BIT0[= 0] Graphics updated by SDMA [= 1] by CPU
375 	 * BIT1[= 0] Compute updated by SDMA [= 1] by CPU
376 	 */
377 	int					vm_update_mode;
378 
379 	/* PASID to VM mapping, will be used in interrupt context to
380 	 * look up VM of a page fault
381 	 */
382 	struct xarray				pasids;
383 };
384 
385 struct amdgpu_bo_va_mapping;
386 
387 #define amdgpu_vm_copy_pte(adev, ib, pe, src, count) ((adev)->vm_manager.vm_pte_funcs->copy_pte((ib), (pe), (src), (count)))
388 #define amdgpu_vm_write_pte(adev, ib, pe, value, count, incr) ((adev)->vm_manager.vm_pte_funcs->write_pte((ib), (pe), (value), (count), (incr)))
389 #define amdgpu_vm_set_pte_pde(adev, ib, pe, addr, count, incr, flags) ((adev)->vm_manager.vm_pte_funcs->set_pte_pde((ib), (pe), (addr), (count), (incr), (flags)))
390 
391 extern const struct amdgpu_vm_update_funcs amdgpu_vm_cpu_funcs;
392 extern const struct amdgpu_vm_update_funcs amdgpu_vm_sdma_funcs;
393 
394 void amdgpu_vm_manager_init(struct amdgpu_device *adev);
395 void amdgpu_vm_manager_fini(struct amdgpu_device *adev);
396 
397 int amdgpu_vm_set_pasid(struct amdgpu_device *adev, struct amdgpu_vm *vm,
398 			u32 pasid);
399 
400 long amdgpu_vm_wait_idle(struct amdgpu_vm *vm, long timeout);
401 int amdgpu_vm_init(struct amdgpu_device *adev, struct amdgpu_vm *vm);
402 int amdgpu_vm_make_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm);
403 void amdgpu_vm_release_compute(struct amdgpu_device *adev, struct amdgpu_vm *vm);
404 void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm);
405 void amdgpu_vm_get_pd_bo(struct amdgpu_vm *vm,
406 			 struct list_head *validated,
407 			 struct amdgpu_bo_list_entry *entry);
408 bool amdgpu_vm_ready(struct amdgpu_vm *vm);
409 uint64_t amdgpu_vm_generation(struct amdgpu_device *adev, struct amdgpu_vm *vm);
410 int amdgpu_vm_validate_pt_bos(struct amdgpu_device *adev, struct amdgpu_vm *vm,
411 			      int (*callback)(void *p, struct amdgpu_bo *bo),
412 			      void *param);
413 int amdgpu_vm_flush(struct amdgpu_ring *ring, struct amdgpu_job *job, bool need_pipe_sync);
414 int amdgpu_vm_update_pdes(struct amdgpu_device *adev,
415 			  struct amdgpu_vm *vm, bool immediate);
416 int amdgpu_vm_clear_freed(struct amdgpu_device *adev,
417 			  struct amdgpu_vm *vm,
418 			  struct dma_fence **fence);
419 int amdgpu_vm_handle_moved(struct amdgpu_device *adev,
420 			   struct amdgpu_vm *vm);
421 void amdgpu_vm_bo_base_init(struct amdgpu_vm_bo_base *base,
422 			    struct amdgpu_vm *vm, struct amdgpu_bo *bo);
423 int amdgpu_vm_update_range(struct amdgpu_device *adev, struct amdgpu_vm *vm,
424 			   bool immediate, bool unlocked, bool flush_tlb,
425 			   struct dma_resv *resv, uint64_t start, uint64_t last,
426 			   uint64_t flags, uint64_t offset, uint64_t vram_base,
427 			   struct ttm_resource *res, dma_addr_t *pages_addr,
428 			   struct dma_fence **fence);
429 int amdgpu_vm_bo_update(struct amdgpu_device *adev,
430 			struct amdgpu_bo_va *bo_va,
431 			bool clear);
432 bool amdgpu_vm_evictable(struct amdgpu_bo *bo);
433 void amdgpu_vm_bo_invalidate(struct amdgpu_device *adev,
434 			     struct amdgpu_bo *bo, bool evicted);
435 uint64_t amdgpu_vm_map_gart(const dma_addr_t *pages_addr, uint64_t addr);
436 struct amdgpu_bo_va *amdgpu_vm_bo_find(struct amdgpu_vm *vm,
437 				       struct amdgpu_bo *bo);
438 struct amdgpu_bo_va *amdgpu_vm_bo_add(struct amdgpu_device *adev,
439 				      struct amdgpu_vm *vm,
440 				      struct amdgpu_bo *bo);
441 int amdgpu_vm_bo_map(struct amdgpu_device *adev,
442 		     struct amdgpu_bo_va *bo_va,
443 		     uint64_t addr, uint64_t offset,
444 		     uint64_t size, uint64_t flags);
445 int amdgpu_vm_bo_replace_map(struct amdgpu_device *adev,
446 			     struct amdgpu_bo_va *bo_va,
447 			     uint64_t addr, uint64_t offset,
448 			     uint64_t size, uint64_t flags);
449 int amdgpu_vm_bo_unmap(struct amdgpu_device *adev,
450 		       struct amdgpu_bo_va *bo_va,
451 		       uint64_t addr);
452 int amdgpu_vm_bo_clear_mappings(struct amdgpu_device *adev,
453 				struct amdgpu_vm *vm,
454 				uint64_t saddr, uint64_t size);
455 struct amdgpu_bo_va_mapping *amdgpu_vm_bo_lookup_mapping(struct amdgpu_vm *vm,
456 							 uint64_t addr);
457 void amdgpu_vm_bo_trace_cs(struct amdgpu_vm *vm, struct ww_acquire_ctx *ticket);
458 void amdgpu_vm_bo_del(struct amdgpu_device *adev,
459 		      struct amdgpu_bo_va *bo_va);
460 void amdgpu_vm_adjust_size(struct amdgpu_device *adev, uint32_t min_vm_size,
461 			   uint32_t fragment_size_default, unsigned max_level,
462 			   unsigned max_bits);
463 int amdgpu_vm_ioctl(struct drm_device *dev, void *data, struct drm_file *filp);
464 bool amdgpu_vm_need_pipeline_sync(struct amdgpu_ring *ring,
465 				  struct amdgpu_job *job);
466 void amdgpu_vm_check_compute_bug(struct amdgpu_device *adev);
467 
468 void amdgpu_vm_get_task_info(struct amdgpu_device *adev, u32 pasid,
469 			     struct amdgpu_task_info *task_info);
470 bool amdgpu_vm_handle_fault(struct amdgpu_device *adev, u32 pasid,
471 			    u32 vmid, u32 node_id, uint64_t addr,
472 			    bool write_fault);
473 
474 void amdgpu_vm_set_task_info(struct amdgpu_vm *vm);
475 
476 void amdgpu_vm_move_to_lru_tail(struct amdgpu_device *adev,
477 				struct amdgpu_vm *vm);
478 void amdgpu_vm_get_memory(struct amdgpu_vm *vm,
479 			  struct amdgpu_mem_stats *stats);
480 
481 int amdgpu_vm_pt_clear(struct amdgpu_device *adev, struct amdgpu_vm *vm,
482 		       struct amdgpu_bo_vm *vmbo, bool immediate);
483 int amdgpu_vm_pt_create(struct amdgpu_device *adev, struct amdgpu_vm *vm,
484 			int level, bool immediate, struct amdgpu_bo_vm **vmbo);
485 void amdgpu_vm_pt_free_root(struct amdgpu_device *adev, struct amdgpu_vm *vm);
486 bool amdgpu_vm_pt_is_root_clean(struct amdgpu_device *adev,
487 				struct amdgpu_vm *vm);
488 
489 int amdgpu_vm_pde_update(struct amdgpu_vm_update_params *params,
490 			 struct amdgpu_vm_bo_base *entry);
491 int amdgpu_vm_ptes_update(struct amdgpu_vm_update_params *params,
492 			  uint64_t start, uint64_t end,
493 			  uint64_t dst, uint64_t flags);
494 void amdgpu_vm_pt_free_work(struct work_struct *work);
495 
496 #if defined(CONFIG_DEBUG_FS)
497 void amdgpu_debugfs_vm_bo_info(struct amdgpu_vm *vm, struct seq_file *m);
498 #endif
499 
500 int amdgpu_vm_pt_map_tables(struct amdgpu_device *adev, struct amdgpu_vm *vm);
501 
502 /**
503  * amdgpu_vm_tlb_seq - return tlb flush sequence number
504  * @vm: the amdgpu_vm structure to query
505  *
506  * Returns the tlb flush sequence number which indicates that the VM TLBs needs
507  * to be invalidated whenever the sequence number change.
508  */
509 static inline uint64_t amdgpu_vm_tlb_seq(struct amdgpu_vm *vm)
510 {
511 	unsigned long flags;
512 	spinlock_t *lock;
513 
514 	/*
515 	 * Workaround to stop racing between the fence signaling and handling
516 	 * the cb. The lock is static after initially setting it up, just make
517 	 * sure that the dma_fence structure isn't freed up.
518 	 */
519 	rcu_read_lock();
520 	lock = vm->last_tlb_flush->lock;
521 	rcu_read_unlock();
522 
523 	spin_lock_irqsave(lock, flags);
524 	spin_unlock_irqrestore(lock, flags);
525 
526 	return atomic64_read(&vm->tlb_seq);
527 }
528 
529 /*
530  * vm eviction_lock can be taken in MMU notifiers. Make sure no reclaim-FS
531  * happens while holding this lock anywhere to prevent deadlocks when
532  * an MMU notifier runs in reclaim-FS context.
533  */
534 static inline void amdgpu_vm_eviction_lock(struct amdgpu_vm *vm)
535 {
536 	mutex_lock(&vm->eviction_lock);
537 	vm->saved_flags = memalloc_noreclaim_save();
538 }
539 
540 static inline bool amdgpu_vm_eviction_trylock(struct amdgpu_vm *vm)
541 {
542 	if (mutex_trylock(&vm->eviction_lock)) {
543 		vm->saved_flags = memalloc_noreclaim_save();
544 		return true;
545 	}
546 	return false;
547 }
548 
549 static inline void amdgpu_vm_eviction_unlock(struct amdgpu_vm *vm)
550 {
551 	memalloc_noreclaim_restore(vm->saved_flags);
552 	mutex_unlock(&vm->eviction_lock);
553 }
554 
555 #endif
556