xref: /linux/drivers/gpu/drm/panthor/panthor_gem.c (revision 3027ce13e04eee76539ca65c2cb1028a01c8c508)
1 // SPDX-License-Identifier: GPL-2.0 or MIT
2 /* Copyright 2019 Linaro, Ltd, Rob Herring <robh@kernel.org> */
3 /* Copyright 2023 Collabora ltd. */
4 
5 #include <linux/dma-buf.h>
6 #include <linux/dma-mapping.h>
7 #include <linux/err.h>
8 #include <linux/slab.h>
9 
10 #include <drm/panthor_drm.h>
11 
12 #include "panthor_device.h"
13 #include "panthor_gem.h"
14 #include "panthor_mmu.h"
15 
16 static void panthor_gem_free_object(struct drm_gem_object *obj)
17 {
18 	struct panthor_gem_object *bo = to_panthor_bo(obj);
19 	struct drm_gem_object *vm_root_gem = bo->exclusive_vm_root_gem;
20 
21 	drm_gem_free_mmap_offset(&bo->base.base);
22 	mutex_destroy(&bo->gpuva_list_lock);
23 	drm_gem_shmem_free(&bo->base);
24 	drm_gem_object_put(vm_root_gem);
25 }
26 
27 /**
28  * panthor_kernel_bo_destroy() - Destroy a kernel buffer object
29  * @vm: The VM this BO was mapped to.
30  * @bo: Kernel buffer object to destroy. If NULL or an ERR_PTR(), the destruction
31  * is skipped.
32  */
33 void panthor_kernel_bo_destroy(struct panthor_vm *vm,
34 			       struct panthor_kernel_bo *bo)
35 {
36 	int ret;
37 
38 	if (IS_ERR_OR_NULL(bo))
39 		return;
40 
41 	panthor_kernel_bo_vunmap(bo);
42 
43 	if (drm_WARN_ON(bo->obj->dev,
44 			to_panthor_bo(bo->obj)->exclusive_vm_root_gem != panthor_vm_root_gem(vm)))
45 		goto out_free_bo;
46 
47 	ret = panthor_vm_unmap_range(vm, bo->va_node.start,
48 				     panthor_kernel_bo_size(bo));
49 	if (ret)
50 		goto out_free_bo;
51 
52 	panthor_vm_free_va(vm, &bo->va_node);
53 	drm_gem_object_put(bo->obj);
54 
55 out_free_bo:
56 	kfree(bo);
57 }
58 
59 /**
60  * panthor_kernel_bo_create() - Create and map a GEM object to a VM
61  * @ptdev: Device.
62  * @vm: VM to map the GEM to. If NULL, the kernel object is not GPU mapped.
63  * @size: Size of the buffer object.
64  * @bo_flags: Combination of drm_panthor_bo_flags flags.
65  * @vm_map_flags: Combination of drm_panthor_vm_bind_op_flags (only those
66  * that are related to map operations).
67  * @gpu_va: GPU address assigned when mapping to the VM.
68  * If gpu_va == PANTHOR_VM_KERNEL_AUTO_VA, the virtual address will be
69  * automatically allocated.
70  *
71  * Return: A valid pointer in case of success, an ERR_PTR() otherwise.
72  */
73 struct panthor_kernel_bo *
74 panthor_kernel_bo_create(struct panthor_device *ptdev, struct panthor_vm *vm,
75 			 size_t size, u32 bo_flags, u32 vm_map_flags,
76 			 u64 gpu_va)
77 {
78 	struct drm_gem_shmem_object *obj;
79 	struct panthor_kernel_bo *kbo;
80 	struct panthor_gem_object *bo;
81 	int ret;
82 
83 	if (drm_WARN_ON(&ptdev->base, !vm))
84 		return ERR_PTR(-EINVAL);
85 
86 	kbo = kzalloc(sizeof(*kbo), GFP_KERNEL);
87 	if (!kbo)
88 		return ERR_PTR(-ENOMEM);
89 
90 	obj = drm_gem_shmem_create(&ptdev->base, size);
91 	if (IS_ERR(obj)) {
92 		ret = PTR_ERR(obj);
93 		goto err_free_bo;
94 	}
95 
96 	bo = to_panthor_bo(&obj->base);
97 	size = obj->base.size;
98 	kbo->obj = &obj->base;
99 	bo->flags = bo_flags;
100 
101 	ret = panthor_vm_alloc_va(vm, gpu_va, size, &kbo->va_node);
102 	if (ret)
103 		goto err_put_obj;
104 
105 	ret = panthor_vm_map_bo_range(vm, bo, 0, size, kbo->va_node.start, vm_map_flags);
106 	if (ret)
107 		goto err_free_va;
108 
109 	bo->exclusive_vm_root_gem = panthor_vm_root_gem(vm);
110 	drm_gem_object_get(bo->exclusive_vm_root_gem);
111 	bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
112 	return kbo;
113 
114 err_free_va:
115 	panthor_vm_free_va(vm, &kbo->va_node);
116 
117 err_put_obj:
118 	drm_gem_object_put(&obj->base);
119 
120 err_free_bo:
121 	kfree(kbo);
122 	return ERR_PTR(ret);
123 }
124 
125 static int panthor_gem_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma)
126 {
127 	struct panthor_gem_object *bo = to_panthor_bo(obj);
128 
129 	/* Don't allow mmap on objects that have the NO_MMAP flag set. */
130 	if (bo->flags & DRM_PANTHOR_BO_NO_MMAP)
131 		return -EINVAL;
132 
133 	return drm_gem_shmem_object_mmap(obj, vma);
134 }
135 
136 static struct dma_buf *
137 panthor_gem_prime_export(struct drm_gem_object *obj, int flags)
138 {
139 	/* We can't export GEMs that have an exclusive VM. */
140 	if (to_panthor_bo(obj)->exclusive_vm_root_gem)
141 		return ERR_PTR(-EINVAL);
142 
143 	return drm_gem_prime_export(obj, flags);
144 }
145 
146 static const struct drm_gem_object_funcs panthor_gem_funcs = {
147 	.free = panthor_gem_free_object,
148 	.print_info = drm_gem_shmem_object_print_info,
149 	.pin = drm_gem_shmem_object_pin,
150 	.unpin = drm_gem_shmem_object_unpin,
151 	.get_sg_table = drm_gem_shmem_object_get_sg_table,
152 	.vmap = drm_gem_shmem_object_vmap,
153 	.vunmap = drm_gem_shmem_object_vunmap,
154 	.mmap = panthor_gem_mmap,
155 	.export = panthor_gem_prime_export,
156 	.vm_ops = &drm_gem_shmem_vm_ops,
157 };
158 
159 /**
160  * panthor_gem_create_object - Implementation of driver->gem_create_object.
161  * @ddev: DRM device
162  * @size: Size in bytes of the memory the object will reference
163  *
164  * This lets the GEM helpers allocate object structs for us, and keep
165  * our BO stats correct.
166  */
167 struct drm_gem_object *panthor_gem_create_object(struct drm_device *ddev, size_t size)
168 {
169 	struct panthor_device *ptdev = container_of(ddev, struct panthor_device, base);
170 	struct panthor_gem_object *obj;
171 
172 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
173 	if (!obj)
174 		return ERR_PTR(-ENOMEM);
175 
176 	obj->base.base.funcs = &panthor_gem_funcs;
177 	obj->base.map_wc = !ptdev->coherent;
178 	mutex_init(&obj->gpuva_list_lock);
179 	drm_gem_gpuva_set_lock(&obj->base.base, &obj->gpuva_list_lock);
180 
181 	return &obj->base.base;
182 }
183 
184 /**
185  * panthor_gem_create_with_handle() - Create a GEM object and attach it to a handle.
186  * @file: DRM file.
187  * @ddev: DRM device.
188  * @exclusive_vm: Exclusive VM. Not NULL if the GEM object can't be shared.
189  * @size: Size of the GEM object to allocate.
190  * @flags: Combination of drm_panthor_bo_flags flags.
191  * @handle: Pointer holding the handle pointing to the new GEM object.
192  *
193  * Return: Zero on success
194  */
195 int
196 panthor_gem_create_with_handle(struct drm_file *file,
197 			       struct drm_device *ddev,
198 			       struct panthor_vm *exclusive_vm,
199 			       u64 *size, u32 flags, u32 *handle)
200 {
201 	int ret;
202 	struct drm_gem_shmem_object *shmem;
203 	struct panthor_gem_object *bo;
204 
205 	shmem = drm_gem_shmem_create(ddev, *size);
206 	if (IS_ERR(shmem))
207 		return PTR_ERR(shmem);
208 
209 	bo = to_panthor_bo(&shmem->base);
210 	bo->flags = flags;
211 
212 	if (exclusive_vm) {
213 		bo->exclusive_vm_root_gem = panthor_vm_root_gem(exclusive_vm);
214 		drm_gem_object_get(bo->exclusive_vm_root_gem);
215 		bo->base.base.resv = bo->exclusive_vm_root_gem->resv;
216 	}
217 
218 	/*
219 	 * Allocate an id of idr table where the obj is registered
220 	 * and handle has the id what user can see.
221 	 */
222 	ret = drm_gem_handle_create(file, &shmem->base, handle);
223 	if (!ret)
224 		*size = bo->base.base.size;
225 
226 	/* drop reference from allocate - handle holds it now. */
227 	drm_gem_object_put(&shmem->base);
228 
229 	return ret;
230 }
231