1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * Copyright (C) 2012 Red Hat
  4 */
  5
  6#include <linux/dma-buf.h>
  7#include <linux/vmalloc.h>
  8
  9#include <drm/drm_mode.h>
 10#include <drm/drm_prime.h>
 11
 12#include "udl_drv.h"
 13
 14struct udl_gem_object *udl_gem_alloc_object(struct drm_device *dev,
 15					    size_t size)
 16{
 17	struct udl_gem_object *obj;
 18
 19	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 20	if (obj == NULL)
 21		return NULL;
 22
 23	if (drm_gem_object_init(dev, &obj->base, size) != 0) {
 24		kfree(obj);
 25		return NULL;
 26	}
 27
 28	obj->flags = UDL_BO_CACHEABLE;
 29	return obj;
 30}
 31
 32static int
 33udl_gem_create(struct drm_file *file,
 34	       struct drm_device *dev,
 35	       uint64_t size,
 36	       uint32_t *handle_p)
 37{
 38	struct udl_gem_object *obj;
 39	int ret;
 40	u32 handle;
 41
 42	size = roundup(size, PAGE_SIZE);
 43
 44	obj = udl_gem_alloc_object(dev, size);
 45	if (obj == NULL)
 46		return -ENOMEM;
 47
 48	ret = drm_gem_handle_create(file, &obj->base, &handle);
 49	if (ret) {
 50		drm_gem_object_release(&obj->base);
 51		kfree(obj);
 52		return ret;
 53	}
 54
 55	drm_gem_object_put_unlocked(&obj->base);
 56	*handle_p = handle;
 57	return 0;
 58}
 59
 60static void update_vm_cache_attr(struct udl_gem_object *obj,
 61				 struct vm_area_struct *vma)
 62{
 63	DRM_DEBUG_KMS("flags = 0x%x\n", obj->flags);
 64
 65	/* non-cacheable as default. */
 66	if (obj->flags & UDL_BO_CACHEABLE) {
 67		vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 68	} else if (obj->flags & UDL_BO_WC) {
 69		vma->vm_page_prot =
 70			pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
 71	} else {
 72		vma->vm_page_prot =
 73			pgprot_noncached(vm_get_page_prot(vma->vm_flags));
 74	}
 75}
 76
 77int udl_dumb_create(struct drm_file *file,
 78		    struct drm_device *dev,
 79		    struct drm_mode_create_dumb *args)
 80{
 81	args->pitch = args->width * DIV_ROUND_UP(args->bpp, 8);
 82	args->size = args->pitch * args->height;
 83	return udl_gem_create(file, dev,
 84			      args->size, &args->handle);
 85}
 86
 87int udl_drm_gem_mmap(struct file *filp, struct vm_area_struct *vma)
 88{
 89	int ret;
 90
 91	ret = drm_gem_mmap(filp, vma);
 92	if (ret)
 93		return ret;
 94
 95	vma->vm_flags &= ~VM_PFNMAP;
 96	vma->vm_flags |= VM_MIXEDMAP;
 97
 98	update_vm_cache_attr(to_udl_bo(vma->vm_private_data), vma);
 99
100	return ret;
101}
102
103vm_fault_t udl_gem_fault(struct vm_fault *vmf)
104{
105	struct vm_area_struct *vma = vmf->vma;
106	struct udl_gem_object *obj = to_udl_bo(vma->vm_private_data);
107	struct page *page;
108	unsigned int page_offset;
109
110	page_offset = (vmf->address - vma->vm_start) >> PAGE_SHIFT;
111
112	if (!obj->pages)
113		return VM_FAULT_SIGBUS;
114
115	page = obj->pages[page_offset];
116	return vmf_insert_page(vma, vmf->address, page);
117}
118
119int udl_gem_get_pages(struct udl_gem_object *obj)
120{
121	struct page **pages;
122
123	if (obj->pages)
124		return 0;
125
126	pages = drm_gem_get_pages(&obj->base);
127	if (IS_ERR(pages))
128		return PTR_ERR(pages);
129
130	obj->pages = pages;
131
132	return 0;
133}
134
135void udl_gem_put_pages(struct udl_gem_object *obj)
136{
137	if (obj->base.import_attach) {
138		kvfree(obj->pages);
139		obj->pages = NULL;
140		return;
141	}
142
143	drm_gem_put_pages(&obj->base, obj->pages, false, false);
144	obj->pages = NULL;
145}
146
147int udl_gem_vmap(struct udl_gem_object *obj)
148{
149	int page_count = obj->base.size / PAGE_SIZE;
150	int ret;
151
152	if (obj->base.import_attach) {
153		obj->vmapping = dma_buf_vmap(obj->base.import_attach->dmabuf);
154		if (!obj->vmapping)
155			return -ENOMEM;
156		return 0;
157	}
158		
159	ret = udl_gem_get_pages(obj);
160	if (ret)
161		return ret;
162
163	obj->vmapping = vmap(obj->pages, page_count, 0, PAGE_KERNEL);
164	if (!obj->vmapping)
165		return -ENOMEM;
166	return 0;
167}
168
169void udl_gem_vunmap(struct udl_gem_object *obj)
170{
171	if (obj->base.import_attach) {
172		dma_buf_vunmap(obj->base.import_attach->dmabuf, obj->vmapping);
173		return;
174	}
175
176	vunmap(obj->vmapping);
177
178	udl_gem_put_pages(obj);
179}
180
181void udl_gem_free_object(struct drm_gem_object *gem_obj)
182{
183	struct udl_gem_object *obj = to_udl_bo(gem_obj);
184
185	if (obj->vmapping)
186		udl_gem_vunmap(obj);
187
188	if (gem_obj->import_attach) {
189		drm_prime_gem_destroy(gem_obj, obj->sg);
190		put_device(gem_obj->dev->dev);
191	}
192
193	if (obj->pages)
194		udl_gem_put_pages(obj);
195
196	drm_gem_free_mmap_offset(gem_obj);
197}
198
199/* the dumb interface doesn't work with the GEM straight MMAP
200   interface, it expects to do MMAP on the drm fd, like normal */
201int udl_gem_mmap(struct drm_file *file, struct drm_device *dev,
202		 uint32_t handle, uint64_t *offset)
203{
204	struct udl_gem_object *gobj;
205	struct drm_gem_object *obj;
206	struct udl_device *udl = to_udl(dev);
207	int ret = 0;
208
209	mutex_lock(&udl->gem_lock);
210	obj = drm_gem_object_lookup(file, handle);
211	if (obj == NULL) {
212		ret = -ENOENT;
213		goto unlock;
214	}
215	gobj = to_udl_bo(obj);
216
217	ret = udl_gem_get_pages(gobj);
218	if (ret)
219		goto out;
220	ret = drm_gem_create_mmap_offset(obj);
221	if (ret)
222		goto out;
223
224	*offset = drm_vma_node_offset_addr(&gobj->base.vma_node);
225
226out:
227	drm_gem_object_put_unlocked(&gobj->base);
228unlock:
229	mutex_unlock(&udl->gem_lock);
230	return ret;
231}