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 = (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	ret = vm_insert_page(vma, vmf->address, page);
117	switch (ret) {
118	case -EAGAIN:
119	case 0:
120	case -ERESTARTSYS:
121		return VM_FAULT_NOPAGE;
122	case -ENOMEM:
123		return VM_FAULT_OOM;
124	default:
125		return VM_FAULT_SIGBUS;
126	}
127}
128
129int udl_gem_get_pages(struct udl_gem_object *obj)
130{
131	struct page **pages;
132
133	if (obj->pages)
134		return 0;
135
136	pages = drm_gem_get_pages(&obj->base);
137	if (IS_ERR(pages))
138		return PTR_ERR(pages);
139
140	obj->pages = pages;
141
142	return 0;
143}
144
145void udl_gem_put_pages(struct udl_gem_object *obj)
146{
147	if (obj->base.import_attach) {
148		drm_free_large(obj->pages);
149		obj->pages = NULL;
150		return;
151	}
152
153	drm_gem_put_pages(&obj->base, obj->pages, false, false);
154	obj->pages = NULL;
155}
156
157int udl_gem_vmap(struct udl_gem_object *obj)
158{
159	int page_count = obj->base.size / PAGE_SIZE;
160	int ret;
161
162	if (obj->base.import_attach) {
163		obj->vmapping = dma_buf_vmap(obj->base.import_attach->dmabuf);
164		if (!obj->vmapping)
165			return -ENOMEM;
166		return 0;
167	}
168		
169	ret = udl_gem_get_pages(obj);
170	if (ret)
171		return ret;
172
173	obj->vmapping = vmap(obj->pages, page_count, 0, PAGE_KERNEL);
174	if (!obj->vmapping)
175		return -ENOMEM;
176	return 0;
177}
178
179void udl_gem_vunmap(struct udl_gem_object *obj)
180{
181	if (obj->base.import_attach) {
182		dma_buf_vunmap(obj->base.import_attach->dmabuf, obj->vmapping);
183		return;
184	}
185
186	vunmap(obj->vmapping);
187
188	udl_gem_put_pages(obj);
189}
190
191void udl_gem_free_object(struct drm_gem_object *gem_obj)
192{
193	struct udl_gem_object *obj = to_udl_bo(gem_obj);
194
195	if (obj->vmapping)
196		udl_gem_vunmap(obj);
197
198	if (gem_obj->import_attach) {
199		drm_prime_gem_destroy(gem_obj, obj->sg);
200		put_device(gem_obj->dev->dev);
201	}
202
203	if (obj->pages)
204		udl_gem_put_pages(obj);
205
206	drm_gem_free_mmap_offset(gem_obj);
207}
208
209/* the dumb interface doesn't work with the GEM straight MMAP
210   interface, it expects to do MMAP on the drm fd, like normal */
211int udl_gem_mmap(struct drm_file *file, struct drm_device *dev,
212		 uint32_t handle, uint64_t *offset)
213{
214	struct udl_gem_object *gobj;
215	struct drm_gem_object *obj;
216	int ret = 0;
217
218	mutex_lock(&dev->struct_mutex);
219	obj = drm_gem_object_lookup(file, handle);
220	if (obj == NULL) {
221		ret = -ENOENT;
222		goto unlock;
223	}
224	gobj = to_udl_bo(obj);
225
226	ret = udl_gem_get_pages(gobj);
227	if (ret)
228		goto out;
229	ret = drm_gem_create_mmap_offset(obj);
230	if (ret)
231		goto out;
232
233	*offset = drm_vma_node_offset_addr(&gobj->base.vma_node);
234
235out:
236	drm_gem_object_unreference(&gobj->base);
237unlock:
238	mutex_unlock(&dev->struct_mutex);
239	return ret;
240}