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1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#define pr_fmt(fmt) "[TTM] " fmt
32
33#include <ttm/ttm_module.h>
34#include <ttm/ttm_bo_driver.h>
35#include <ttm/ttm_placement.h>
36#include <drm/drm_vma_manager.h>
37#include <linux/mm.h>
38#include <linux/pfn_t.h>
39#include <linux/rbtree.h>
40#include <linux/module.h>
41#include <linux/uaccess.h>
42
43#define TTM_BO_VM_NUM_PREFAULT 16
44
45static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
46 struct vm_area_struct *vma,
47 struct vm_fault *vmf)
48{
49 int ret = 0;
50
51 if (likely(!test_bit(TTM_BO_PRIV_FLAG_MOVING, &bo->priv_flags)))
52 goto out_unlock;
53
54 /*
55 * Quick non-stalling check for idle.
56 */
57 ret = ttm_bo_wait(bo, false, false, true);
58 if (likely(ret == 0))
59 goto out_unlock;
60
61 /*
62 * If possible, avoid waiting for GPU with mmap_sem
63 * held.
64 */
65 if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
66 ret = VM_FAULT_RETRY;
67 if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
68 goto out_unlock;
69
70 up_read(&vma->vm_mm->mmap_sem);
71 (void) ttm_bo_wait(bo, false, true, false);
72 goto out_unlock;
73 }
74
75 /*
76 * Ordinary wait.
77 */
78 ret = ttm_bo_wait(bo, false, true, false);
79 if (unlikely(ret != 0))
80 ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
81 VM_FAULT_NOPAGE;
82
83out_unlock:
84 return ret;
85}
86
87static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
88{
89 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
90 vma->vm_private_data;
91 struct ttm_bo_device *bdev = bo->bdev;
92 unsigned long page_offset;
93 unsigned long page_last;
94 unsigned long pfn;
95 struct ttm_tt *ttm = NULL;
96 struct page *page;
97 int ret;
98 int i;
99 unsigned long address = (unsigned long)vmf->virtual_address;
100 int retval = VM_FAULT_NOPAGE;
101 struct ttm_mem_type_manager *man =
102 &bdev->man[bo->mem.mem_type];
103 struct vm_area_struct cvma;
104
105 /*
106 * Work around locking order reversal in fault / nopfn
107 * between mmap_sem and bo_reserve: Perform a trylock operation
108 * for reserve, and if it fails, retry the fault after waiting
109 * for the buffer to become unreserved.
110 */
111 ret = ttm_bo_reserve(bo, true, true, false, NULL);
112 if (unlikely(ret != 0)) {
113 if (ret != -EBUSY)
114 return VM_FAULT_NOPAGE;
115
116 if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
117 if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
118 up_read(&vma->vm_mm->mmap_sem);
119 (void) ttm_bo_wait_unreserved(bo);
120 }
121
122 return VM_FAULT_RETRY;
123 }
124
125 /*
126 * If we'd want to change locking order to
127 * mmap_sem -> bo::reserve, we'd use a blocking reserve here
128 * instead of retrying the fault...
129 */
130 return VM_FAULT_NOPAGE;
131 }
132
133 /*
134 * Refuse to fault imported pages. This should be handled
135 * (if at all) by redirecting mmap to the exporter.
136 */
137 if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
138 retval = VM_FAULT_SIGBUS;
139 goto out_unlock;
140 }
141
142 if (bdev->driver->fault_reserve_notify) {
143 ret = bdev->driver->fault_reserve_notify(bo);
144 switch (ret) {
145 case 0:
146 break;
147 case -EBUSY:
148 case -ERESTARTSYS:
149 retval = VM_FAULT_NOPAGE;
150 goto out_unlock;
151 default:
152 retval = VM_FAULT_SIGBUS;
153 goto out_unlock;
154 }
155 }
156
157 /*
158 * Wait for buffer data in transit, due to a pipelined
159 * move.
160 */
161 ret = ttm_bo_vm_fault_idle(bo, vma, vmf);
162 if (unlikely(ret != 0)) {
163 retval = ret;
164 goto out_unlock;
165 }
166
167 ret = ttm_mem_io_lock(man, true);
168 if (unlikely(ret != 0)) {
169 retval = VM_FAULT_NOPAGE;
170 goto out_unlock;
171 }
172 ret = ttm_mem_io_reserve_vm(bo);
173 if (unlikely(ret != 0)) {
174 retval = VM_FAULT_SIGBUS;
175 goto out_io_unlock;
176 }
177
178 page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
179 vma->vm_pgoff - drm_vma_node_start(&bo->vma_node);
180 page_last = vma_pages(vma) + vma->vm_pgoff -
181 drm_vma_node_start(&bo->vma_node);
182
183 if (unlikely(page_offset >= bo->num_pages)) {
184 retval = VM_FAULT_SIGBUS;
185 goto out_io_unlock;
186 }
187
188 /*
189 * Make a local vma copy to modify the page_prot member
190 * and vm_flags if necessary. The vma parameter is protected
191 * by mmap_sem in write mode.
192 */
193 cvma = *vma;
194 cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
195
196 if (bo->mem.bus.is_iomem) {
197 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
198 cvma.vm_page_prot);
199 } else {
200 ttm = bo->ttm;
201 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
202 cvma.vm_page_prot);
203
204 /* Allocate all page at once, most common usage */
205 if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
206 retval = VM_FAULT_OOM;
207 goto out_io_unlock;
208 }
209 }
210
211 /*
212 * Speculatively prefault a number of pages. Only error on
213 * first page.
214 */
215 for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
216 if (bo->mem.bus.is_iomem)
217 pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
218 else {
219 page = ttm->pages[page_offset];
220 if (unlikely(!page && i == 0)) {
221 retval = VM_FAULT_OOM;
222 goto out_io_unlock;
223 } else if (unlikely(!page)) {
224 break;
225 }
226 page->mapping = vma->vm_file->f_mapping;
227 page->index = drm_vma_node_start(&bo->vma_node) +
228 page_offset;
229 pfn = page_to_pfn(page);
230 }
231
232 if (vma->vm_flags & VM_MIXEDMAP)
233 ret = vm_insert_mixed(&cvma, address,
234 __pfn_to_pfn_t(pfn, PFN_DEV));
235 else
236 ret = vm_insert_pfn(&cvma, address, pfn);
237
238 /*
239 * Somebody beat us to this PTE or prefaulting to
240 * an already populated PTE, or prefaulting error.
241 */
242
243 if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
244 break;
245 else if (unlikely(ret != 0)) {
246 retval =
247 (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
248 goto out_io_unlock;
249 }
250
251 address += PAGE_SIZE;
252 if (unlikely(++page_offset >= page_last))
253 break;
254 }
255out_io_unlock:
256 ttm_mem_io_unlock(man);
257out_unlock:
258 ttm_bo_unreserve(bo);
259 return retval;
260}
261
262static void ttm_bo_vm_open(struct vm_area_struct *vma)
263{
264 struct ttm_buffer_object *bo =
265 (struct ttm_buffer_object *)vma->vm_private_data;
266
267 WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);
268
269 (void)ttm_bo_reference(bo);
270}
271
272static void ttm_bo_vm_close(struct vm_area_struct *vma)
273{
274 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;
275
276 ttm_bo_unref(&bo);
277 vma->vm_private_data = NULL;
278}
279
280static const struct vm_operations_struct ttm_bo_vm_ops = {
281 .fault = ttm_bo_vm_fault,
282 .open = ttm_bo_vm_open,
283 .close = ttm_bo_vm_close
284};
285
286static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev,
287 unsigned long offset,
288 unsigned long pages)
289{
290 struct drm_vma_offset_node *node;
291 struct ttm_buffer_object *bo = NULL;
292
293 drm_vma_offset_lock_lookup(&bdev->vma_manager);
294
295 node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
296 if (likely(node)) {
297 bo = container_of(node, struct ttm_buffer_object, vma_node);
298 if (!kref_get_unless_zero(&bo->kref))
299 bo = NULL;
300 }
301
302 drm_vma_offset_unlock_lookup(&bdev->vma_manager);
303
304 if (!bo)
305 pr_err("Could not find buffer object to map\n");
306
307 return bo;
308}
309
310int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
311 struct ttm_bo_device *bdev)
312{
313 struct ttm_bo_driver *driver;
314 struct ttm_buffer_object *bo;
315 int ret;
316
317 bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
318 if (unlikely(!bo))
319 return -EINVAL;
320
321 driver = bo->bdev->driver;
322 if (unlikely(!driver->verify_access)) {
323 ret = -EPERM;
324 goto out_unref;
325 }
326 ret = driver->verify_access(bo, filp);
327 if (unlikely(ret != 0))
328 goto out_unref;
329
330 vma->vm_ops = &ttm_bo_vm_ops;
331
332 /*
333 * Note: We're transferring the bo reference to
334 * vma->vm_private_data here.
335 */
336
337 vma->vm_private_data = bo;
338
339 /*
340 * We'd like to use VM_PFNMAP on shared mappings, where
341 * (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
342 * but for some reason VM_PFNMAP + x86 PAT + write-combine is very
343 * bad for performance. Until that has been sorted out, use
344 * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
345 */
346 vma->vm_flags |= VM_MIXEDMAP;
347 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
348 return 0;
349out_unref:
350 ttm_bo_unref(&bo);
351 return ret;
352}
353EXPORT_SYMBOL(ttm_bo_mmap);
354
355int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
356{
357 if (vma->vm_pgoff != 0)
358 return -EACCES;
359
360 vma->vm_ops = &ttm_bo_vm_ops;
361 vma->vm_private_data = ttm_bo_reference(bo);
362 vma->vm_flags |= VM_MIXEDMAP;
363 vma->vm_flags |= VM_IO | VM_DONTEXPAND;
364 return 0;
365}
366EXPORT_SYMBOL(ttm_fbdev_mmap);
1/**************************************************************************
2 *
3 * Copyright (c) 2006-2009 VMware, Inc., Palo Alto, CA., USA
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
20 * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
21 * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
22 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
23 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
24 * USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27/*
28 * Authors: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
29 */
30
31#define pr_fmt(fmt) "[TTM] " fmt
32
33#include <ttm/ttm_module.h>
34#include <ttm/ttm_bo_driver.h>
35#include <ttm/ttm_placement.h>
36#include <drm/drm_vma_manager.h>
37#include <linux/mm.h>
38#include <linux/pfn_t.h>
39#include <linux/rbtree.h>
40#include <linux/module.h>
41#include <linux/uaccess.h>
42
43#define TTM_BO_VM_NUM_PREFAULT 16
44
45static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
46 struct vm_area_struct *vma,
47 struct vm_fault *vmf)
48{
49 int ret = 0;
50
51 if (likely(!bo->moving))
52 goto out_unlock;
53
54 /*
55 * Quick non-stalling check for idle.
56 */
57 if (dma_fence_is_signaled(bo->moving))
58 goto out_clear;
59
60 /*
61 * If possible, avoid waiting for GPU with mmap_sem
62 * held.
63 */
64 if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
65 ret = VM_FAULT_RETRY;
66 if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT)
67 goto out_unlock;
68
69 up_read(&vma->vm_mm->mmap_sem);
70 (void) dma_fence_wait(bo->moving, true);
71 goto out_unlock;
72 }
73
74 /*
75 * Ordinary wait.
76 */
77 ret = dma_fence_wait(bo->moving, true);
78 if (unlikely(ret != 0)) {
79 ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
80 VM_FAULT_NOPAGE;
81 goto out_unlock;
82 }
83
84out_clear:
85 dma_fence_put(bo->moving);
86 bo->moving = NULL;
87
88out_unlock:
89 return ret;
90}
91
92static int ttm_bo_vm_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
93{
94 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
95 vma->vm_private_data;
96 struct ttm_bo_device *bdev = bo->bdev;
97 unsigned long page_offset;
98 unsigned long page_last;
99 unsigned long pfn;
100 struct ttm_tt *ttm = NULL;
101 struct page *page;
102 int ret;
103 int i;
104 unsigned long address = vmf->address;
105 int retval = VM_FAULT_NOPAGE;
106 struct ttm_mem_type_manager *man =
107 &bdev->man[bo->mem.mem_type];
108 struct vm_area_struct cvma;
109
110 /*
111 * Work around locking order reversal in fault / nopfn
112 * between mmap_sem and bo_reserve: Perform a trylock operation
113 * for reserve, and if it fails, retry the fault after waiting
114 * for the buffer to become unreserved.
115 */
116 ret = ttm_bo_reserve(bo, true, true, NULL);
117 if (unlikely(ret != 0)) {
118 if (ret != -EBUSY)
119 return VM_FAULT_NOPAGE;
120
121 if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
122 if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
123 up_read(&vma->vm_mm->mmap_sem);
124 (void) ttm_bo_wait_unreserved(bo);
125 }
126
127 return VM_FAULT_RETRY;
128 }
129
130 /*
131 * If we'd want to change locking order to
132 * mmap_sem -> bo::reserve, we'd use a blocking reserve here
133 * instead of retrying the fault...
134 */
135 return VM_FAULT_NOPAGE;
136 }
137
138 /*
139 * Refuse to fault imported pages. This should be handled
140 * (if at all) by redirecting mmap to the exporter.
141 */
142 if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
143 retval = VM_FAULT_SIGBUS;
144 goto out_unlock;
145 }
146
147 if (bdev->driver->fault_reserve_notify) {
148 ret = bdev->driver->fault_reserve_notify(bo);
149 switch (ret) {
150 case 0:
151 break;
152 case -EBUSY:
153 case -ERESTARTSYS:
154 retval = VM_FAULT_NOPAGE;
155 goto out_unlock;
156 default:
157 retval = VM_FAULT_SIGBUS;
158 goto out_unlock;
159 }
160 }
161
162 /*
163 * Wait for buffer data in transit, due to a pipelined
164 * move.
165 */
166 ret = ttm_bo_vm_fault_idle(bo, vma, vmf);
167 if (unlikely(ret != 0)) {
168 retval = ret;
169 goto out_unlock;
170 }
171
172 ret = ttm_mem_io_lock(man, true);
173 if (unlikely(ret != 0)) {
174 retval = VM_FAULT_NOPAGE;
175 goto out_unlock;
176 }
177 ret = ttm_mem_io_reserve_vm(bo);
178 if (unlikely(ret != 0)) {
179 retval = VM_FAULT_SIGBUS;
180 goto out_io_unlock;
181 }
182
183 page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
184 vma->vm_pgoff - drm_vma_node_start(&bo->vma_node);
185 page_last = vma_pages(vma) + vma->vm_pgoff -
186 drm_vma_node_start(&bo->vma_node);
187
188 if (unlikely(page_offset >= bo->num_pages)) {
189 retval = VM_FAULT_SIGBUS;
190 goto out_io_unlock;
191 }
192
193 /*
194 * Make a local vma copy to modify the page_prot member
195 * and vm_flags if necessary. The vma parameter is protected
196 * by mmap_sem in write mode.
197 */
198 cvma = *vma;
199 cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
200
201 if (bo->mem.bus.is_iomem) {
202 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
203 cvma.vm_page_prot);
204 } else {
205 ttm = bo->ttm;
206 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
207 cvma.vm_page_prot);
208
209 /* Allocate all page at once, most common usage */
210 if (ttm->bdev->driver->ttm_tt_populate(ttm)) {
211 retval = VM_FAULT_OOM;
212 goto out_io_unlock;
213 }
214 }
215
216 /*
217 * Speculatively prefault a number of pages. Only error on
218 * first page.
219 */
220 for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
221 if (bo->mem.bus.is_iomem)
222 pfn = ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT) + page_offset;
223 else {
224 page = ttm->pages[page_offset];
225 if (unlikely(!page && i == 0)) {
226 retval = VM_FAULT_OOM;
227 goto out_io_unlock;
228 } else if (unlikely(!page)) {
229 break;
230 }
231 page->mapping = vma->vm_file->f_mapping;
232 page->index = drm_vma_node_start(&bo->vma_node) +
233 page_offset;
234 pfn = page_to_pfn(page);
235 }
236
237 if (vma->vm_flags & VM_MIXEDMAP)
238 ret = vm_insert_mixed(&cvma, address,
239 __pfn_to_pfn_t(pfn, PFN_DEV));
240 else
241 ret = vm_insert_pfn(&cvma, address, pfn);
242
243 /*
244 * Somebody beat us to this PTE or prefaulting to
245 * an already populated PTE, or prefaulting error.
246 */
247
248 if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
249 break;
250 else if (unlikely(ret != 0)) {
251 retval =
252 (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
253 goto out_io_unlock;
254 }
255
256 address += PAGE_SIZE;
257 if (unlikely(++page_offset >= page_last))
258 break;
259 }
260out_io_unlock:
261 ttm_mem_io_unlock(man);
262out_unlock:
263 ttm_bo_unreserve(bo);
264 return retval;
265}
266
267static void ttm_bo_vm_open(struct vm_area_struct *vma)
268{
269 struct ttm_buffer_object *bo =
270 (struct ttm_buffer_object *)vma->vm_private_data;
271
272 WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);
273
274 (void)ttm_bo_reference(bo);
275}
276
277static void ttm_bo_vm_close(struct vm_area_struct *vma)
278{
279 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;
280
281 ttm_bo_unref(&bo);
282 vma->vm_private_data = NULL;
283}
284
285static const struct vm_operations_struct ttm_bo_vm_ops = {
286 .fault = ttm_bo_vm_fault,
287 .open = ttm_bo_vm_open,
288 .close = ttm_bo_vm_close
289};
290
291static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev,
292 unsigned long offset,
293 unsigned long pages)
294{
295 struct drm_vma_offset_node *node;
296 struct ttm_buffer_object *bo = NULL;
297
298 drm_vma_offset_lock_lookup(&bdev->vma_manager);
299
300 node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
301 if (likely(node)) {
302 bo = container_of(node, struct ttm_buffer_object, vma_node);
303 if (!kref_get_unless_zero(&bo->kref))
304 bo = NULL;
305 }
306
307 drm_vma_offset_unlock_lookup(&bdev->vma_manager);
308
309 if (!bo)
310 pr_err("Could not find buffer object to map\n");
311
312 return bo;
313}
314
315int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
316 struct ttm_bo_device *bdev)
317{
318 struct ttm_bo_driver *driver;
319 struct ttm_buffer_object *bo;
320 int ret;
321
322 bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
323 if (unlikely(!bo))
324 return -EINVAL;
325
326 driver = bo->bdev->driver;
327 if (unlikely(!driver->verify_access)) {
328 ret = -EPERM;
329 goto out_unref;
330 }
331 ret = driver->verify_access(bo, filp);
332 if (unlikely(ret != 0))
333 goto out_unref;
334
335 vma->vm_ops = &ttm_bo_vm_ops;
336
337 /*
338 * Note: We're transferring the bo reference to
339 * vma->vm_private_data here.
340 */
341
342 vma->vm_private_data = bo;
343
344 /*
345 * We'd like to use VM_PFNMAP on shared mappings, where
346 * (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
347 * but for some reason VM_PFNMAP + x86 PAT + write-combine is very
348 * bad for performance. Until that has been sorted out, use
349 * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
350 */
351 vma->vm_flags |= VM_MIXEDMAP;
352 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
353 return 0;
354out_unref:
355 ttm_bo_unref(&bo);
356 return ret;
357}
358EXPORT_SYMBOL(ttm_bo_mmap);
359
360int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
361{
362 if (vma->vm_pgoff != 0)
363 return -EACCES;
364
365 vma->vm_ops = &ttm_bo_vm_ops;
366 vma->vm_private_data = ttm_bo_reference(bo);
367 vma->vm_flags |= VM_MIXEDMAP;
368 vma->vm_flags |= VM_IO | VM_DONTEXPAND;
369 return 0;
370}
371EXPORT_SYMBOL(ttm_fbdev_mmap);