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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 <drm/ttm/ttm_module.h>
34#include <drm/ttm/ttm_bo_driver.h>
35#include <drm/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#include <linux/mem_encrypt.h>
43
44#define TTM_BO_VM_NUM_PREFAULT 16
45
46static int ttm_bo_vm_fault_idle(struct ttm_buffer_object *bo,
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 ttm_bo_reference(bo);
70 up_read(&vmf->vma->vm_mm->mmap_sem);
71 (void) dma_fence_wait(bo->moving, true);
72 ttm_bo_unreserve(bo);
73 ttm_bo_unref(&bo);
74 goto out_unlock;
75 }
76
77 /*
78 * Ordinary wait.
79 */
80 ret = dma_fence_wait(bo->moving, true);
81 if (unlikely(ret != 0)) {
82 ret = (ret != -ERESTARTSYS) ? VM_FAULT_SIGBUS :
83 VM_FAULT_NOPAGE;
84 goto out_unlock;
85 }
86
87out_clear:
88 dma_fence_put(bo->moving);
89 bo->moving = NULL;
90
91out_unlock:
92 return ret;
93}
94
95static unsigned long ttm_bo_io_mem_pfn(struct ttm_buffer_object *bo,
96 unsigned long page_offset)
97{
98 struct ttm_bo_device *bdev = bo->bdev;
99
100 if (bdev->driver->io_mem_pfn)
101 return bdev->driver->io_mem_pfn(bo, page_offset);
102
103 return ((bo->mem.bus.base + bo->mem.bus.offset) >> PAGE_SHIFT)
104 + page_offset;
105}
106
107static int ttm_bo_vm_fault(struct vm_fault *vmf)
108{
109 struct vm_area_struct *vma = vmf->vma;
110 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)
111 vma->vm_private_data;
112 struct ttm_bo_device *bdev = bo->bdev;
113 unsigned long page_offset;
114 unsigned long page_last;
115 unsigned long pfn;
116 struct ttm_tt *ttm = NULL;
117 struct page *page;
118 int ret;
119 int i;
120 unsigned long address = vmf->address;
121 struct ttm_mem_type_manager *man =
122 &bdev->man[bo->mem.mem_type];
123 struct vm_area_struct cvma;
124
125 /*
126 * Work around locking order reversal in fault / nopfn
127 * between mmap_sem and bo_reserve: Perform a trylock operation
128 * for reserve, and if it fails, retry the fault after waiting
129 * for the buffer to become unreserved.
130 */
131 ret = ttm_bo_reserve(bo, true, true, NULL);
132 if (unlikely(ret != 0)) {
133 if (ret != -EBUSY)
134 return VM_FAULT_NOPAGE;
135
136 if (vmf->flags & FAULT_FLAG_ALLOW_RETRY) {
137 if (!(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
138 ttm_bo_reference(bo);
139 up_read(&vmf->vma->vm_mm->mmap_sem);
140 (void) ttm_bo_wait_unreserved(bo);
141 ttm_bo_unref(&bo);
142 }
143
144 return VM_FAULT_RETRY;
145 }
146
147 /*
148 * If we'd want to change locking order to
149 * mmap_sem -> bo::reserve, we'd use a blocking reserve here
150 * instead of retrying the fault...
151 */
152 return VM_FAULT_NOPAGE;
153 }
154
155 /*
156 * Refuse to fault imported pages. This should be handled
157 * (if at all) by redirecting mmap to the exporter.
158 */
159 if (bo->ttm && (bo->ttm->page_flags & TTM_PAGE_FLAG_SG)) {
160 ret = VM_FAULT_SIGBUS;
161 goto out_unlock;
162 }
163
164 if (bdev->driver->fault_reserve_notify) {
165 ret = bdev->driver->fault_reserve_notify(bo);
166 switch (ret) {
167 case 0:
168 break;
169 case -EBUSY:
170 case -ERESTARTSYS:
171 ret = VM_FAULT_NOPAGE;
172 goto out_unlock;
173 default:
174 ret = VM_FAULT_SIGBUS;
175 goto out_unlock;
176 }
177 }
178
179 /*
180 * Wait for buffer data in transit, due to a pipelined
181 * move.
182 */
183 ret = ttm_bo_vm_fault_idle(bo, vmf);
184 if (unlikely(ret != 0)) {
185 if (ret == VM_FAULT_RETRY &&
186 !(vmf->flags & FAULT_FLAG_RETRY_NOWAIT)) {
187 /* The BO has already been unreserved. */
188 return ret;
189 }
190
191 goto out_unlock;
192 }
193
194 ret = ttm_mem_io_lock(man, true);
195 if (unlikely(ret != 0)) {
196 ret = VM_FAULT_NOPAGE;
197 goto out_unlock;
198 }
199 ret = ttm_mem_io_reserve_vm(bo);
200 if (unlikely(ret != 0)) {
201 ret = VM_FAULT_SIGBUS;
202 goto out_io_unlock;
203 }
204
205 page_offset = ((address - vma->vm_start) >> PAGE_SHIFT) +
206 vma->vm_pgoff - drm_vma_node_start(&bo->vma_node);
207 page_last = vma_pages(vma) + vma->vm_pgoff -
208 drm_vma_node_start(&bo->vma_node);
209
210 if (unlikely(page_offset >= bo->num_pages)) {
211 ret = VM_FAULT_SIGBUS;
212 goto out_io_unlock;
213 }
214
215 /*
216 * Make a local vma copy to modify the page_prot member
217 * and vm_flags if necessary. The vma parameter is protected
218 * by mmap_sem in write mode.
219 */
220 cvma = *vma;
221 cvma.vm_page_prot = vm_get_page_prot(cvma.vm_flags);
222
223 if (bo->mem.bus.is_iomem) {
224 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
225 cvma.vm_page_prot);
226 } else {
227 struct ttm_operation_ctx ctx = {
228 .interruptible = false,
229 .no_wait_gpu = false,
230 .flags = TTM_OPT_FLAG_FORCE_ALLOC
231
232 };
233
234 ttm = bo->ttm;
235 cvma.vm_page_prot = ttm_io_prot(bo->mem.placement,
236 cvma.vm_page_prot);
237
238 /* Allocate all page at once, most common usage */
239 if (ttm_tt_populate(ttm, &ctx)) {
240 ret = VM_FAULT_OOM;
241 goto out_io_unlock;
242 }
243 }
244
245 /*
246 * Speculatively prefault a number of pages. Only error on
247 * first page.
248 */
249 for (i = 0; i < TTM_BO_VM_NUM_PREFAULT; ++i) {
250 if (bo->mem.bus.is_iomem) {
251 /* Iomem should not be marked encrypted */
252 cvma.vm_page_prot = pgprot_decrypted(cvma.vm_page_prot);
253 pfn = ttm_bo_io_mem_pfn(bo, page_offset);
254 } else {
255 page = ttm->pages[page_offset];
256 if (unlikely(!page && i == 0)) {
257 ret = VM_FAULT_OOM;
258 goto out_io_unlock;
259 } else if (unlikely(!page)) {
260 break;
261 }
262 page->index = drm_vma_node_start(&bo->vma_node) +
263 page_offset;
264 pfn = page_to_pfn(page);
265 }
266
267 if (vma->vm_flags & VM_MIXEDMAP)
268 ret = vm_insert_mixed(&cvma, address,
269 __pfn_to_pfn_t(pfn, PFN_DEV));
270 else
271 ret = vm_insert_pfn(&cvma, address, pfn);
272
273 /*
274 * Somebody beat us to this PTE or prefaulting to
275 * an already populated PTE, or prefaulting error.
276 */
277
278 if (unlikely((ret == -EBUSY) || (ret != 0 && i > 0)))
279 break;
280 else if (unlikely(ret != 0)) {
281 ret =
282 (ret == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS;
283 goto out_io_unlock;
284 }
285
286 address += PAGE_SIZE;
287 if (unlikely(++page_offset >= page_last))
288 break;
289 }
290 ret = VM_FAULT_NOPAGE;
291out_io_unlock:
292 ttm_mem_io_unlock(man);
293out_unlock:
294 ttm_bo_unreserve(bo);
295 return ret;
296}
297
298static void ttm_bo_vm_open(struct vm_area_struct *vma)
299{
300 struct ttm_buffer_object *bo =
301 (struct ttm_buffer_object *)vma->vm_private_data;
302
303 WARN_ON(bo->bdev->dev_mapping != vma->vm_file->f_mapping);
304
305 (void)ttm_bo_reference(bo);
306}
307
308static void ttm_bo_vm_close(struct vm_area_struct *vma)
309{
310 struct ttm_buffer_object *bo = (struct ttm_buffer_object *)vma->vm_private_data;
311
312 ttm_bo_unref(&bo);
313 vma->vm_private_data = NULL;
314}
315
316static int ttm_bo_vm_access_kmap(struct ttm_buffer_object *bo,
317 unsigned long offset,
318 uint8_t *buf, int len, int write)
319{
320 unsigned long page = offset >> PAGE_SHIFT;
321 unsigned long bytes_left = len;
322 int ret;
323
324 /* Copy a page at a time, that way no extra virtual address
325 * mapping is needed
326 */
327 offset -= page << PAGE_SHIFT;
328 do {
329 unsigned long bytes = min(bytes_left, PAGE_SIZE - offset);
330 struct ttm_bo_kmap_obj map;
331 void *ptr;
332 bool is_iomem;
333
334 ret = ttm_bo_kmap(bo, page, 1, &map);
335 if (ret)
336 return ret;
337
338 ptr = (uint8_t *)ttm_kmap_obj_virtual(&map, &is_iomem) + offset;
339 WARN_ON_ONCE(is_iomem);
340 if (write)
341 memcpy(ptr, buf, bytes);
342 else
343 memcpy(buf, ptr, bytes);
344 ttm_bo_kunmap(&map);
345
346 page++;
347 buf += bytes;
348 bytes_left -= bytes;
349 offset = 0;
350 } while (bytes_left);
351
352 return len;
353}
354
355static int ttm_bo_vm_access(struct vm_area_struct *vma, unsigned long addr,
356 void *buf, int len, int write)
357{
358 unsigned long offset = (addr) - vma->vm_start;
359 struct ttm_buffer_object *bo = vma->vm_private_data;
360 int ret;
361
362 if (len < 1 || (offset + len) >> PAGE_SHIFT > bo->num_pages)
363 return -EIO;
364
365 ret = ttm_bo_reserve(bo, true, false, NULL);
366 if (ret)
367 return ret;
368
369 switch (bo->mem.mem_type) {
370 case TTM_PL_SYSTEM:
371 if (unlikely(bo->ttm->page_flags & TTM_PAGE_FLAG_SWAPPED)) {
372 ret = ttm_tt_swapin(bo->ttm);
373 if (unlikely(ret != 0))
374 return ret;
375 }
376 /* fall through */
377 case TTM_PL_TT:
378 ret = ttm_bo_vm_access_kmap(bo, offset, buf, len, write);
379 break;
380 default:
381 if (bo->bdev->driver->access_memory)
382 ret = bo->bdev->driver->access_memory(
383 bo, offset, buf, len, write);
384 else
385 ret = -EIO;
386 }
387
388 ttm_bo_unreserve(bo);
389
390 return ret;
391}
392
393static const struct vm_operations_struct ttm_bo_vm_ops = {
394 .fault = ttm_bo_vm_fault,
395 .open = ttm_bo_vm_open,
396 .close = ttm_bo_vm_close,
397 .access = ttm_bo_vm_access
398};
399
400static struct ttm_buffer_object *ttm_bo_vm_lookup(struct ttm_bo_device *bdev,
401 unsigned long offset,
402 unsigned long pages)
403{
404 struct drm_vma_offset_node *node;
405 struct ttm_buffer_object *bo = NULL;
406
407 drm_vma_offset_lock_lookup(&bdev->vma_manager);
408
409 node = drm_vma_offset_lookup_locked(&bdev->vma_manager, offset, pages);
410 if (likely(node)) {
411 bo = container_of(node, struct ttm_buffer_object, vma_node);
412 if (!kref_get_unless_zero(&bo->kref))
413 bo = NULL;
414 }
415
416 drm_vma_offset_unlock_lookup(&bdev->vma_manager);
417
418 if (!bo)
419 pr_err("Could not find buffer object to map\n");
420
421 return bo;
422}
423
424int ttm_bo_mmap(struct file *filp, struct vm_area_struct *vma,
425 struct ttm_bo_device *bdev)
426{
427 struct ttm_bo_driver *driver;
428 struct ttm_buffer_object *bo;
429 int ret;
430
431 bo = ttm_bo_vm_lookup(bdev, vma->vm_pgoff, vma_pages(vma));
432 if (unlikely(!bo))
433 return -EINVAL;
434
435 driver = bo->bdev->driver;
436 if (unlikely(!driver->verify_access)) {
437 ret = -EPERM;
438 goto out_unref;
439 }
440 ret = driver->verify_access(bo, filp);
441 if (unlikely(ret != 0))
442 goto out_unref;
443
444 vma->vm_ops = &ttm_bo_vm_ops;
445
446 /*
447 * Note: We're transferring the bo reference to
448 * vma->vm_private_data here.
449 */
450
451 vma->vm_private_data = bo;
452
453 /*
454 * We'd like to use VM_PFNMAP on shared mappings, where
455 * (vma->vm_flags & VM_SHARED) != 0, for performance reasons,
456 * but for some reason VM_PFNMAP + x86 PAT + write-combine is very
457 * bad for performance. Until that has been sorted out, use
458 * VM_MIXEDMAP on all mappings. See freedesktop.org bug #75719
459 */
460 vma->vm_flags |= VM_MIXEDMAP;
461 vma->vm_flags |= VM_IO | VM_DONTEXPAND | VM_DONTDUMP;
462 return 0;
463out_unref:
464 ttm_bo_unref(&bo);
465 return ret;
466}
467EXPORT_SYMBOL(ttm_bo_mmap);
468
469int ttm_fbdev_mmap(struct vm_area_struct *vma, struct ttm_buffer_object *bo)
470{
471 if (vma->vm_pgoff != 0)
472 return -EACCES;
473
474 vma->vm_ops = &ttm_bo_vm_ops;
475 vma->vm_private_data = ttm_bo_reference(bo);
476 vma->vm_flags |= VM_MIXEDMAP;
477 vma->vm_flags |= VM_IO | VM_DONTEXPAND;
478 return 0;
479}
480EXPORT_SYMBOL(ttm_fbdev_mmap);