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.
56  * @node_size: Size of the allocated range manager node.
57  * @vma_size: Bind size.
58  * @page_sizes_gtt: Resulting page sizes from the bind operation.
59  * @bound_flags: Flags indicating binding status.
60  * @allocated: Backend private data. TODO: Should move into @private.
61  * @immediate_unbind: Unbind can be done immediately and doesn't need to be
62  * deferred to a work item awaiting unsignaled fences. This is a hack.
63  * (dma_fence_work uses a fence flag for this, but this seems slightly
64  * cleaner).
65  * @needs_wakeref: Whether a wakeref is needed during unbind. Since we can't
66  * take a wakeref in the dma-fence signalling critical path, it needs to be
67  * taken when the unbind is scheduled.
68  * @skip_pte_rewrite: During ggtt suspend and vm takedown pte rewriting
69  * needs to be skipped for unbind.
70  * @tlb: pointer for obj->mm.tlb, if async unbind. Otherwise, NULL
71  *
72  * The lifetime of a struct i915_vma_resource is from a binding request to
73  * the actual possible asynchronous unbind has completed.
74  */
75 struct i915_vma_resource {
76 	struct dma_fence unbind_fence;
77 	/* See above for description of the lock. */
78 	spinlock_t lock;
79 	refcount_t hold_count;
80 	struct work_struct work;
81 	struct i915_sw_fence chain;
82 	struct rb_node rb;
83 	u64 __subtree_last;
84 	struct i915_address_space *vm;
85 	intel_wakeref_t wakeref;
86 
87 	/**
88 	 * struct i915_vma_bindinfo - Information needed for async bind
89 	 * only but that can be dropped after the bind has taken place.
90 	 * Consider making this a separate argument to the bind_vma
91 	 * op, coalescing with other arguments like vm, stash, cache_level
92 	 * and flags
93 	 * @pages: The pages sg-table.
94 	 * @page_sizes: Page sizes of the pages.
95 	 * @pages_rsgt: Refcounted sg-table when delayed object destruction
96 	 * is supported. May be NULL.
97 	 * @readonly: Whether the vma should be bound read-only.
98 	 * @lmem: Whether the vma points to lmem.
99 	 */
100 	struct i915_vma_bindinfo {
101 		struct sg_table *pages;
102 		struct i915_page_sizes page_sizes;
103 		struct i915_refct_sgt *pages_rsgt;
104 		bool readonly:1;
105 		bool lmem:1;
106 	} bi;
107 
108 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
109 	struct intel_memory_region *mr;
110 #endif
111 	const struct i915_vma_ops *ops;
112 	void *private;
113 	u64 start;
114 	u64 node_size;
115 	u64 vma_size;
116 	u32 page_sizes_gtt;
117 
118 	u32 bound_flags;
119 	bool allocated:1;
120 	bool immediate_unbind:1;
121 	bool needs_wakeref:1;
122 	bool skip_pte_rewrite:1;
123 
124 	u32 *tlb;
125 };
126 
127 bool i915_vma_resource_hold(struct i915_vma_resource *vma_res,
128 			    bool *lockdep_cookie);
129 
130 void i915_vma_resource_unhold(struct i915_vma_resource *vma_res,
131 			      bool lockdep_cookie);
132 
133 struct i915_vma_resource *i915_vma_resource_alloc(void);
134 
135 void i915_vma_resource_free(struct i915_vma_resource *vma_res);
136 
137 struct dma_fence *i915_vma_resource_unbind(struct i915_vma_resource *vma_res,
138 					   u32 *tlb);
139 
140 void __i915_vma_resource_init(struct i915_vma_resource *vma_res);
141 
142 /**
143  * i915_vma_resource_get - Take a reference on a vma resource
144  * @vma_res: The vma resource on which to take a reference.
145  *
146  * Return: The @vma_res pointer
147  */
148 static inline struct i915_vma_resource
149 *i915_vma_resource_get(struct i915_vma_resource *vma_res)
150 {
151 	dma_fence_get(&vma_res->unbind_fence);
152 	return vma_res;
153 }
154 
155 /**
156  * i915_vma_resource_put - Release a reference to a struct i915_vma_resource
157  * @vma_res: The resource
158  */
159 static inline void i915_vma_resource_put(struct i915_vma_resource *vma_res)
160 {
161 	dma_fence_put(&vma_res->unbind_fence);
162 }
163 
164 /**
165  * i915_vma_resource_init - Initialize a vma resource.
166  * @vma_res: The vma resource to initialize
167  * @vm: Pointer to the vm.
168  * @pages: The pages sg-table.
169  * @page_sizes: Page sizes of the pages.
170  * @pages_rsgt: Pointer to a struct i915_refct_sgt of an object with
171  * delayed destruction.
172  * @readonly: Whether the vma should be bound read-only.
173  * @lmem: Whether the vma points to lmem.
174  * @mr: The memory region of the object the vma points to.
175  * @ops: The backend ops.
176  * @private: Bind backend private info.
177  * @start: Offset into the address space of bind range start.
178  * @node_size: Size of the allocated range manager node.
179  * @size: Bind size.
180  *
181  * Initializes a vma resource allocated using i915_vma_resource_alloc().
182  * The reason for having separate allocate and initialize function is that
183  * initialization may need to be performed from under a lock where
184  * allocation is not allowed.
185  */
186 static inline void i915_vma_resource_init(struct i915_vma_resource *vma_res,
187 					  struct i915_address_space *vm,
188 					  struct sg_table *pages,
189 					  const struct i915_page_sizes *page_sizes,
190 					  struct i915_refct_sgt *pages_rsgt,
191 					  bool readonly,
192 					  bool lmem,
193 					  struct intel_memory_region *mr,
194 					  const struct i915_vma_ops *ops,
195 					  void *private,
196 					  u64 start,
197 					  u64 node_size,
198 					  u64 size)
199 {
200 	__i915_vma_resource_init(vma_res);
201 	vma_res->vm = vm;
202 	vma_res->bi.pages = pages;
203 	vma_res->bi.page_sizes = *page_sizes;
204 	if (pages_rsgt)
205 		vma_res->bi.pages_rsgt = i915_refct_sgt_get(pages_rsgt);
206 	vma_res->bi.readonly = readonly;
207 	vma_res->bi.lmem = lmem;
208 #if IS_ENABLED(CONFIG_DRM_I915_CAPTURE_ERROR)
209 	vma_res->mr = mr;
210 #endif
211 	vma_res->ops = ops;
212 	vma_res->private = private;
213 	vma_res->start = start;
214 	vma_res->node_size = node_size;
215 	vma_res->vma_size = size;
216 }
217 
218 static inline void i915_vma_resource_fini(struct i915_vma_resource *vma_res)
219 {
220 	GEM_BUG_ON(refcount_read(&vma_res->hold_count) != 1);
221 	if (vma_res->bi.pages_rsgt)
222 		i915_refct_sgt_put(vma_res->bi.pages_rsgt);
223 	i915_sw_fence_fini(&vma_res->chain);
224 }
225 
226 int i915_vma_resource_bind_dep_sync(struct i915_address_space *vm,
227 				    u64 first,
228 				    u64 last,
229 				    bool intr);
230 
231 int i915_vma_resource_bind_dep_await(struct i915_address_space *vm,
232 				     struct i915_sw_fence *sw_fence,
233 				     u64 first,
234 				     u64 last,
235 				     bool intr,
236 				     gfp_t gfp);
237 
238 void i915_vma_resource_bind_dep_sync_all(struct i915_address_space *vm);
239 
240 void i915_vma_resource_module_exit(void);
241 
242 int i915_vma_resource_module_init(void);
243 
244 #endif
245