1/*
  2 * Copyright (C) 2012 Red Hat
  3 *
  4 * This file is subject to the terms and conditions of the GNU General Public
  5 * License v2. See the file COPYING in the main directory of this archive for
  6 * more details.
  7 */
  8
  9#include <drm/drmP.h>
 10#include "udl_drv.h"
 11#include <linux/shmem_fs.h>
 12#include <linux/dma-buf.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_unreference_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
103int udl_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
104{
105	struct udl_gem_object *obj = to_udl_bo(vma->vm_private_data);
106	struct page *page;
107	unsigned int page_offset;
108	int ret = 0;
109
110	page_offset = ((unsigned long)vmf->virtual_address - vma->vm_start) >>
111		PAGE_SHIFT;
112
113	if (!obj->pages)
114		return VM_FAULT_SIGBUS;
115
116	page = obj->pages[page_offset];
117	ret = vm_insert_page(vma, (unsigned long)vmf->virtual_address, page);
118	switch (ret) {
119	case -EAGAIN:
120	case 0:
121	case -ERESTARTSYS:
122		return VM_FAULT_NOPAGE;
123	case -ENOMEM:
124		return VM_FAULT_OOM;
125	default:
126		return VM_FAULT_SIGBUS;
127	}
128}
129
130int udl_gem_get_pages(struct udl_gem_object *obj)
131{
132	struct page **pages;
133
134	if (obj->pages)
135		return 0;
136
137	pages = drm_gem_get_pages(&obj->base);
138	if (IS_ERR(pages))
139		return PTR_ERR(pages);
140
141	obj->pages = pages;
142
143	return 0;
144}
145
146void udl_gem_put_pages(struct udl_gem_object *obj)
147{
148	if (obj->base.import_attach) {
149		drm_free_large(obj->pages);
150		obj->pages = NULL;
151		return;
152	}
153
154	drm_gem_put_pages(&obj->base, obj->pages, false, false);
155	obj->pages = NULL;
156}
157
158int udl_gem_vmap(struct udl_gem_object *obj)
159{
160	int page_count = obj->base.size / PAGE_SIZE;
161	int ret;
162
163	if (obj->base.import_attach) {
164		obj->vmapping = dma_buf_vmap(obj->base.import_attach->dmabuf);
165		if (!obj->vmapping)
166			return -ENOMEM;
167		return 0;
168	}
169		
170	ret = udl_gem_get_pages(obj);
171	if (ret)
172		return ret;
173
174	obj->vmapping = vmap(obj->pages, page_count, 0, PAGE_KERNEL);
175	if (!obj->vmapping)
176		return -ENOMEM;
177	return 0;
178}
179
180void udl_gem_vunmap(struct udl_gem_object *obj)
181{
182	if (obj->base.import_attach) {
183		dma_buf_vunmap(obj->base.import_attach->dmabuf, obj->vmapping);
184		return;
185	}
186
187	vunmap(obj->vmapping);
188
189	udl_gem_put_pages(obj);
190}
191
192void udl_gem_free_object(struct drm_gem_object *gem_obj)
193{
194	struct udl_gem_object *obj = to_udl_bo(gem_obj);
195
196	if (obj->vmapping)
197		udl_gem_vunmap(obj);
198
199	if (gem_obj->import_attach) {
200		drm_prime_gem_destroy(gem_obj, obj->sg);
201		put_device(gem_obj->dev->dev);
202	}
203
204	if (obj->pages)
205		udl_gem_put_pages(obj);
206
207	drm_gem_free_mmap_offset(gem_obj);
208}
209
210/* the dumb interface doesn't work with the GEM straight MMAP
211   interface, it expects to do MMAP on the drm fd, like normal */
212int udl_gem_mmap(struct drm_file *file, struct drm_device *dev,
213		 uint32_t handle, uint64_t *offset)
214{
215	struct udl_gem_object *gobj;
216	struct drm_gem_object *obj;
217	int ret = 0;
218
219	mutex_lock(&dev->struct_mutex);
220	obj = drm_gem_object_lookup(dev, file, handle);
221	if (obj == NULL) {
222		ret = -ENOENT;
223		goto unlock;
224	}
225	gobj = to_udl_bo(obj);
226
227	ret = udl_gem_get_pages(gobj);
228	if (ret)
229		goto out;
230	ret = drm_gem_create_mmap_offset(obj);
231	if (ret)
232		goto out;
233
234	*offset = drm_vma_node_offset_addr(&gobj->base.vma_node);
235
236out:
237	drm_gem_object_unreference(&gobj->base);
238unlock:
239	mutex_unlock(&dev->struct_mutex);
240	return ret;
241}