1 /* SPDX-License-Identifier: MIT */
2 /*
3  * Copyright © 2021 Intel Corporation
4  */
5 
6 #ifndef __I915_VMA_RESOURCE_H__
7 #define __I915_VMA_RESOURCE_H__
8 
9 #include <linux/dma-fence.h>
10 #include <linux/refcount.h>
11 
12 #include "i915_gem.h"
13 #include "i915_scatterlist.h"
14 #include "i915_sw_fence.h"
15 #include "intel_runtime_pm.h"
16 
17 struct intel_memory_region;
18 
19 struct i915_page_sizes {
20 	/**
21 	 * The sg mask of the pages sg_table. i.e the mask of
22 	 * the lengths for each sg entry.
23 	 */
24 	unsigned int phys;
25 
26 	/**
27 	 * The gtt page sizes we are allowed to use given the
28 	 * sg mask and the supported page sizes. This will
29 	 * express the smallest unit we can use for the whole
30 	 * object, as well as the larger sizes we may be able
31 	 * to use opportunistically.
32 	 */
33 	unsigned int sg;
34 };
35 
36 /**
37  * struct i915_vma_resource - Snapshotted unbind information.
38  * @unbind_fence: Fence to mark unbinding complete. Note that this fence
39  * is not considered published until unbind is scheduled, and as such it
40  * is illegal to access this fence before scheduled unbind other than
41  * for refcounting.
42  * @lock: The @unbind_fence lock.
43  * @hold_count: Number of holders blocking the fence from finishing.
44  * The vma itself is keeping a hold, which is released when unbind
45  * is scheduled.
46  * @work: Work struct for deferred unbind work.
47  * @chain: Pointer to struct i915_sw_fence used to await dependencies.
48  * @rb: Rb node for the vm's pending unbind interval tree.
49  * @__subtree_last: Interval tree private member.
50  * @vm: non-refcounted pointer to the vm. This is for internal use only and
51  * this member is cleared after vm_resource unbind.
52  * @mr: The memory region of the object pointed to by the vma.
53  * @ops: Pointer to the backend i915_vma_ops.
54  * @private: Bind backend private info.
55  * @start: Offset into the address space of bind range start. Note that
56  * this is after any padding that might have been allocated.
57  * @node_size: Size of the allocated range manager node with padding
58  * subtracted.
59  * @vma_size: Bind size.
60  * @page_sizes_gtt: Resulting page sizes from the bind operation.
61  * @bound_flags: Flags indicating binding status.
62  * @allocated: Backend private data. TODO: Should move into @private.
63  * @immediate_unbind: Unbind can be done immediately and doesn't need to be
64  * deferred to a work item awaiting unsignaled fences. This is a hack.
65  * (dma_fence_work uses a fence flag for this, but this seems slightly
66  * cleaner).
67  * @needs_wakeref: Whether a wakeref is needed during unbind. Since we can't
68  * take a wakeref in the dma-fence signalling critical path, it needs to be
69  * taken when the unbind is scheduled.
70  * @skip_pte_rewrite: During ggtt suspend and vm takedown pte rewriting
71  * needs to be skipped for unbind.
72  * @tlb: pointer for obj->mm.tlb, if async unbind. Otherwise, NULL
73  *
74  * The lifetime of a struct i915_vma_resource is from a binding request to
75  * the actual possible asynchronous unbind has completed.
76  */
77 struct i915_vma_resource {
78 	struct dma_fence unbind_fence;
79 	/* See above for description of the lock. */
80 	spinlock_t lock;
81 	refcount_t hold_count;
82 	struct work_struct work;
83 	struct i915_sw_fence chain;
84 	struct rb_node rb;
85 	u64 __subtree_last;
86 	struct i915_address_space *vm;
87 	intel_wakeref_t wakeref;
88 
89 	/**
90 	 * struct i915_vma_bindinfo - Information needed for async bind
91 	 * only but that can be dropped after the bind has taken place.
92 	 * Consider making this a separate argument to the bind_vma
93 	 * op, coalescing with other arguments like vm, stash, cache_level
94 	 * and flags
95 	 * @pages: The pages sg-table.
96 	 * @page_sizes: Page sizes of the pages.
97 	 * @pages_rsgt: Refcounted sg-table when delayed object destruction
98 	 * is supported. May be NULL.
99 	 * @readonly: Whether the vma should be bound read-only.
100 	 * @lmem: Whether the vma points to lmem.
101 	 */
102 	struct i915_vma_bindinfo {
103 		struct sg_table *pages;
104 		struct i915_page_sizes page_sizes;
105 		struct i915_refct_sgt *pages_rsgt;
106 		bool readonly:1;
107 		bool lmem:1;
108 	} bi;
109 
110 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
111 	struct intel_memory_region *mr;
112 #endif
113 	const struct i915_vma_ops *ops;
114 	void *private;
115 	u64 start;
116 	u64 node_size;
117 	u64 vma_size;
118 	u32 page_sizes_gtt;
119 
120 	u32 bound_flags;
121 	bool allocated:1;
122 	bool immediate_unbind:1;
123 	bool needs_wakeref:1;
124 	bool skip_pte_rewrite:1;
125 
126 	u32 *tlb;
127 };
128 
129 bool i915_vma_resource_hold(struct i915_vma_resource *vma_res,
130 			    bool *lockdep_cookie);
131 
132 void i915_vma_resource_unhold(struct i915_vma_resource *vma_res,
133 			      bool lockdep_cookie);
134 
135 struct i915_vma_resource *i915_vma_resource_alloc(void);
136 
137 void i915_vma_resource_free(struct i915_vma_resource *vma_res);
138 
139 struct dma_fence *i915_vma_resource_unbind(struct i915_vma_resource *vma_res,
140 					   u32 *tlb);
141 
142 void __i915_vma_resource_init(struct i915_vma_resource *vma_res);
143 
144 /**
145  * i915_vma_resource_get - Take a reference on a vma resource
146  * @vma_res: The vma resource on which to take a reference.
147  *
148  * Return: The @vma_res pointer
149  */
150 static inline struct i915_vma_resource
151 *i915_vma_resource_get(struct i915_vma_resource *vma_res)
152 {
153 	dma_fence_get(&vma_res->unbind_fence);
154 	return vma_res;
155 }
156 
157 /**
158  * i915_vma_resource_put - Release a reference to a struct i915_vma_resource
159  * @vma_res: The resource
160  */
161 static inline void i915_vma_resource_put(struct i915_vma_resource *vma_res)
162 {
163 	dma_fence_put(&vma_res->unbind_fence);
164 }
165 
166 /**
167  * i915_vma_resource_init - Initialize a vma resource.
168  * @vma_res: The vma resource to initialize
169  * @vm: Pointer to the vm.
170  * @pages: The pages sg-table.
171  * @page_sizes: Page sizes of the pages.
172  * @pages_rsgt: Pointer to a struct i915_refct_sgt of an object with
173  * delayed destruction.
174  * @readonly: Whether the vma should be bound read-only.
175  * @lmem: Whether the vma points to lmem.
176  * @mr: The memory region of the object the vma points to.
177  * @ops: The backend ops.
178  * @private: Bind backend private info.
179  * @start: Offset into the address space of bind range start after padding.
180  * @node_size: Size of the allocated range manager node minus padding.
181  * @size: Bind size.
182  *
183  * Initializes a vma resource allocated using i915_vma_resource_alloc().
184  * The reason for having separate allocate and initialize function is that
185  * initialization may need to be performed from under a lock where
186  * allocation is not allowed.
187  */
188 static inline void i915_vma_resource_init(struct i915_vma_resource *vma_res,
189 					  struct i915_address_space *vm,
190 					  struct sg_table *pages,
191 					  const struct i915_page_sizes *page_sizes,
192 					  struct i915_refct_sgt *pages_rsgt,
193 					  bool readonly,
194 					  bool lmem,
195 					  struct intel_memory_region *mr,
196 					  const struct i915_vma_ops *ops,
197 					  void *private,
198 					  u64 start,
199 					  u64 node_size,
200 					  u64 size)
201 {
202 	__i915_vma_resource_init(vma_res);
203 	vma_res->vm = vm;
204 	vma_res->bi.pages = pages;
205 	vma_res->bi.page_sizes = *page_sizes;
206 	if (pages_rsgt)
207 		vma_res->bi.pages_rsgt = i915_refct_sgt_get(pages_rsgt);
208 	vma_res->bi.readonly = readonly;
209 	vma_res->bi.lmem = lmem;
210 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
211 	vma_res->mr = mr;
212 #endif
213 	vma_res->ops = ops;
214 	vma_res->private = private;
215 	vma_res->start = start;
216 	vma_res->node_size = node_size;
217 	vma_res->vma_size = size;
218 }
219 
220 static inline void i915_vma_resource_fini(struct i915_vma_resource *vma_res)
221 {
222 	GEM_BUG_ON(refcount_read(&vma_res->hold_count) != 1);
223 	if (vma_res->bi.pages_rsgt)
224 		i915_refct_sgt_put(vma_res->bi.pages_rsgt);
225 	i915_sw_fence_fini(&vma_res->chain);
226 }
227 
228 int i915_vma_resource_bind_dep_sync(struct i915_address_space *vm,
229 				    u64 first,
230 				    u64 last,
231 				    bool intr);
232 
233 int i915_vma_resource_bind_dep_await(struct i915_address_space *vm,
234 				     struct i915_sw_fence *sw_fence,
235 				     u64 first,
236 				     u64 last,
237 				     bool intr,
238 				     gfp_t gfp);
239 
240 void i915_vma_resource_bind_dep_sync_all(struct i915_address_space *vm);
241 
242 void i915_vma_resource_module_exit(void);
243 
244 int i915_vma_resource_module_init(void);
245 
246 #endif
247