1 | // SPDX-License-Identifier: GPL-2.0 OR MIT |
2 | /************************************************************************** |
3 | * |
4 | * Copyright 2017 VMware, Inc., Palo Alto, CA., USA |
5 | * All Rights Reserved. |
6 | * |
7 | * Permission is hereby granted, free of charge, to any person obtaining a |
8 | * copy of this software and associated documentation files (the |
9 | * "Software"), to deal in the Software without restriction, including |
10 | * without limitation the rights to use, copy, modify, merge, publish, |
11 | * distribute, sub license, and/or sell copies of the Software, and to |
12 | * permit persons to whom the Software is furnished to do so, subject to |
13 | * the following conditions: |
14 | * |
15 | * The above copyright notice and this permission notice (including the |
16 | * next paragraph) shall be included in all copies or substantial portions |
17 | * of the Software. |
18 | * |
19 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
20 | * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
21 | * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL |
22 | * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, |
23 | * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR |
24 | * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE |
25 | * USE OR OTHER DEALINGS IN THE SOFTWARE. |
26 | * |
27 | **************************************************************************/ |
28 | |
29 | #include "vmwgfx_drv.h" |
30 | #include <linux/highmem.h> |
31 | |
32 | /* |
33 | * Template that implements find_first_diff() for a generic |
34 | * unsigned integer type. @size and return value are in bytes. |
35 | */ |
36 | #define VMW_FIND_FIRST_DIFF(_type) \ |
37 | static size_t vmw_find_first_diff_ ## _type \ |
38 | (const _type * dst, const _type * src, size_t size)\ |
39 | { \ |
40 | size_t i; \ |
41 | \ |
42 | for (i = 0; i < size; i += sizeof(_type)) { \ |
43 | if (*dst++ != *src++) \ |
44 | break; \ |
45 | } \ |
46 | \ |
47 | return i; \ |
48 | } |
49 | |
50 | |
51 | /* |
52 | * Template that implements find_last_diff() for a generic |
53 | * unsigned integer type. Pointers point to the item following the |
54 | * *end* of the area to be examined. @size and return value are in |
55 | * bytes. |
56 | */ |
57 | #define VMW_FIND_LAST_DIFF(_type) \ |
58 | static ssize_t vmw_find_last_diff_ ## _type( \ |
59 | const _type * dst, const _type * src, size_t size) \ |
60 | { \ |
61 | while (size) { \ |
62 | if (*--dst != *--src) \ |
63 | break; \ |
64 | \ |
65 | size -= sizeof(_type); \ |
66 | } \ |
67 | return size; \ |
68 | } |
69 | |
70 | |
71 | /* |
72 | * Instantiate find diff functions for relevant unsigned integer sizes, |
73 | * assuming that wider integers are faster (including aligning) up to the |
74 | * architecture native width, which is assumed to be 32 bit unless |
75 | * CONFIG_64BIT is defined. |
76 | */ |
77 | VMW_FIND_FIRST_DIFF(u8); |
78 | VMW_FIND_LAST_DIFF(u8); |
79 | |
80 | VMW_FIND_FIRST_DIFF(u16); |
81 | VMW_FIND_LAST_DIFF(u16); |
82 | |
83 | VMW_FIND_FIRST_DIFF(u32); |
84 | VMW_FIND_LAST_DIFF(u32); |
85 | |
86 | #ifdef CONFIG_64BIT |
87 | VMW_FIND_FIRST_DIFF(u64); |
88 | VMW_FIND_LAST_DIFF(u64); |
89 | #endif |
90 | |
91 | |
92 | /* We use size aligned copies. This computes (addr - align(addr)) */ |
93 | #define SPILL(_var, _type) ((unsigned long) _var & (sizeof(_type) - 1)) |
94 | |
95 | |
96 | /* |
97 | * Template to compute find_first_diff() for a certain integer type |
98 | * including a head copy for alignment, and adjustment of parameters |
99 | * for tail find or increased resolution find using an unsigned integer find |
100 | * of smaller width. If finding is complete, and resolution is sufficient, |
101 | * the macro executes a return statement. Otherwise it falls through. |
102 | */ |
103 | #define VMW_TRY_FIND_FIRST_DIFF(_type) \ |
104 | do { \ |
105 | unsigned int spill = SPILL(dst, _type); \ |
106 | size_t diff_offs; \ |
107 | \ |
108 | if (spill && spill == SPILL(src, _type) && \ |
109 | sizeof(_type) - spill <= size) { \ |
110 | spill = sizeof(_type) - spill; \ |
111 | diff_offs = vmw_find_first_diff_u8(dst, src, spill); \ |
112 | if (diff_offs < spill) \ |
113 | return round_down(offset + diff_offs, granularity); \ |
114 | \ |
115 | dst += spill; \ |
116 | src += spill; \ |
117 | size -= spill; \ |
118 | offset += spill; \ |
119 | spill = 0; \ |
120 | } \ |
121 | if (!spill && !SPILL(src, _type)) { \ |
122 | size_t to_copy = size & ~(sizeof(_type) - 1); \ |
123 | \ |
124 | diff_offs = vmw_find_first_diff_ ## _type \ |
125 | ((_type *) dst, (_type *) src, to_copy); \ |
126 | if (diff_offs >= size || granularity == sizeof(_type)) \ |
127 | return (offset + diff_offs); \ |
128 | \ |
129 | dst += diff_offs; \ |
130 | src += diff_offs; \ |
131 | size -= diff_offs; \ |
132 | offset += diff_offs; \ |
133 | } \ |
134 | } while (0) \ |
135 | |
136 | |
137 | /** |
138 | * vmw_find_first_diff - find the first difference between dst and src |
139 | * |
140 | * @dst: The destination address |
141 | * @src: The source address |
142 | * @size: Number of bytes to compare |
143 | * @granularity: The granularity needed for the return value in bytes. |
144 | * return: The offset from find start where the first difference was |
145 | * encountered in bytes. If no difference was found, the function returns |
146 | * a value >= @size. |
147 | */ |
148 | static size_t vmw_find_first_diff(const u8 *dst, const u8 *src, size_t size, |
149 | size_t granularity) |
150 | { |
151 | size_t offset = 0; |
152 | |
153 | /* |
154 | * Try finding with large integers if alignment allows, or we can |
155 | * fix it. Fall through if we need better resolution or alignment |
156 | * was bad. |
157 | */ |
158 | #ifdef CONFIG_64BIT |
159 | VMW_TRY_FIND_FIRST_DIFF(u64); |
160 | #endif |
161 | VMW_TRY_FIND_FIRST_DIFF(u32); |
162 | VMW_TRY_FIND_FIRST_DIFF(u16); |
163 | |
164 | return round_down(offset + vmw_find_first_diff_u8(dst, src, size), |
165 | granularity); |
166 | } |
167 | |
168 | |
169 | /* |
170 | * Template to compute find_last_diff() for a certain integer type |
171 | * including a tail copy for alignment, and adjustment of parameters |
172 | * for head find or increased resolution find using an unsigned integer find |
173 | * of smaller width. If finding is complete, and resolution is sufficient, |
174 | * the macro executes a return statement. Otherwise it falls through. |
175 | */ |
176 | #define VMW_TRY_FIND_LAST_DIFF(_type) \ |
177 | do { \ |
178 | unsigned int spill = SPILL(dst, _type); \ |
179 | ssize_t location; \ |
180 | ssize_t diff_offs; \ |
181 | \ |
182 | if (spill && spill <= size && spill == SPILL(src, _type)) { \ |
183 | diff_offs = vmw_find_last_diff_u8(dst, src, spill); \ |
184 | if (diff_offs) { \ |
185 | location = size - spill + diff_offs - 1; \ |
186 | return round_down(location, granularity); \ |
187 | } \ |
188 | \ |
189 | dst -= spill; \ |
190 | src -= spill; \ |
191 | size -= spill; \ |
192 | spill = 0; \ |
193 | } \ |
194 | if (!spill && !SPILL(src, _type)) { \ |
195 | size_t to_copy = round_down(size, sizeof(_type)); \ |
196 | \ |
197 | diff_offs = vmw_find_last_diff_ ## _type \ |
198 | ((_type *) dst, (_type *) src, to_copy); \ |
199 | location = size - to_copy + diff_offs - sizeof(_type); \ |
200 | if (location < 0 || granularity == sizeof(_type)) \ |
201 | return location; \ |
202 | \ |
203 | dst -= to_copy - diff_offs; \ |
204 | src -= to_copy - diff_offs; \ |
205 | size -= to_copy - diff_offs; \ |
206 | } \ |
207 | } while (0) |
208 | |
209 | |
210 | /** |
211 | * vmw_find_last_diff - find the last difference between dst and src |
212 | * |
213 | * @dst: The destination address |
214 | * @src: The source address |
215 | * @size: Number of bytes to compare |
216 | * @granularity: The granularity needed for the return value in bytes. |
217 | * return: The offset from find start where the last difference was |
218 | * encountered in bytes, or a negative value if no difference was found. |
219 | */ |
220 | static ssize_t vmw_find_last_diff(const u8 *dst, const u8 *src, size_t size, |
221 | size_t granularity) |
222 | { |
223 | dst += size; |
224 | src += size; |
225 | |
226 | #ifdef CONFIG_64BIT |
227 | VMW_TRY_FIND_LAST_DIFF(u64); |
228 | #endif |
229 | VMW_TRY_FIND_LAST_DIFF(u32); |
230 | VMW_TRY_FIND_LAST_DIFF(u16); |
231 | |
232 | return round_down(vmw_find_last_diff_u8(dst, src, size) - 1, |
233 | granularity); |
234 | } |
235 | |
236 | |
237 | /** |
238 | * vmw_memcpy - A wrapper around kernel memcpy with allowing to plug it into a |
239 | * struct vmw_diff_cpy. |
240 | * |
241 | * @diff: The struct vmw_diff_cpy closure argument (unused). |
242 | * @dest: The copy destination. |
243 | * @src: The copy source. |
244 | * @n: Number of bytes to copy. |
245 | */ |
246 | void vmw_memcpy(struct vmw_diff_cpy *diff, u8 *dest, const u8 *src, size_t n) |
247 | { |
248 | memcpy(dest, src, n); |
249 | } |
250 | |
251 | |
252 | /** |
253 | * vmw_adjust_rect - Adjust rectangle coordinates for newly found difference |
254 | * |
255 | * @diff: The struct vmw_diff_cpy used to track the modified bounding box. |
256 | * @diff_offs: The offset from @diff->line_offset where the difference was |
257 | * found. |
258 | */ |
259 | static void vmw_adjust_rect(struct vmw_diff_cpy *diff, size_t diff_offs) |
260 | { |
261 | size_t offs = (diff_offs + diff->line_offset) / diff->cpp; |
262 | struct drm_rect *rect = &diff->rect; |
263 | |
264 | rect->x1 = min_t(int, rect->x1, offs); |
265 | rect->x2 = max_t(int, rect->x2, offs + 1); |
266 | rect->y1 = min_t(int, rect->y1, diff->line); |
267 | rect->y2 = max_t(int, rect->y2, diff->line + 1); |
268 | } |
269 | |
270 | /** |
271 | * vmw_diff_memcpy - memcpy that creates a bounding box of modified content. |
272 | * |
273 | * @diff: The struct vmw_diff_cpy used to track the modified bounding box. |
274 | * @dest: The copy destination. |
275 | * @src: The copy source. |
276 | * @n: Number of bytes to copy. |
277 | * |
278 | * In order to correctly track the modified content, the field @diff->line must |
279 | * be pre-loaded with the current line number, the field @diff->line_offset must |
280 | * be pre-loaded with the line offset in bytes where the copy starts, and |
281 | * finally the field @diff->cpp need to be preloaded with the number of bytes |
282 | * per unit in the horizontal direction of the area we're examining. |
283 | * Typically bytes per pixel. |
284 | * This is needed to know the needed granularity of the difference computing |
285 | * operations. A higher cpp generally leads to faster execution at the cost of |
286 | * bounding box width precision. |
287 | */ |
288 | void vmw_diff_memcpy(struct vmw_diff_cpy *diff, u8 *dest, const u8 *src, |
289 | size_t n) |
290 | { |
291 | ssize_t csize, byte_len; |
292 | |
293 | if (WARN_ON_ONCE(round_down(n, diff->cpp) != n)) |
294 | return; |
295 | |
296 | /* TODO: Possibly use a single vmw_find_first_diff per line? */ |
297 | csize = vmw_find_first_diff(dst: dest, src, size: n, granularity: diff->cpp); |
298 | if (csize < n) { |
299 | vmw_adjust_rect(diff, diff_offs: csize); |
300 | byte_len = diff->cpp; |
301 | |
302 | /* |
303 | * Starting from where first difference was found, find |
304 | * location of last difference, and then copy. |
305 | */ |
306 | diff->line_offset += csize; |
307 | dest += csize; |
308 | src += csize; |
309 | n -= csize; |
310 | csize = vmw_find_last_diff(dst: dest, src, size: n, granularity: diff->cpp); |
311 | if (csize >= 0) { |
312 | byte_len += csize; |
313 | vmw_adjust_rect(diff, diff_offs: csize); |
314 | } |
315 | memcpy(dest, src, byte_len); |
316 | } |
317 | diff->line_offset += n; |
318 | } |
319 | |
320 | /** |
321 | * struct vmw_bo_blit_line_data - Convenience argument to vmw_bo_cpu_blit_line |
322 | * |
323 | * @mapped_dst: Already mapped destination page index in @dst_pages. |
324 | * @dst_addr: Kernel virtual address of mapped destination page. |
325 | * @dst_pages: Array of destination bo pages. |
326 | * @dst_num_pages: Number of destination bo pages. |
327 | * @dst_prot: Destination bo page protection. |
328 | * @mapped_src: Already mapped source page index in @dst_pages. |
329 | * @src_addr: Kernel virtual address of mapped source page. |
330 | * @src_pages: Array of source bo pages. |
331 | * @src_num_pages: Number of source bo pages. |
332 | * @src_prot: Source bo page protection. |
333 | * @diff: Struct vmw_diff_cpy, in the end forwarded to the memcpy routine. |
334 | */ |
335 | struct vmw_bo_blit_line_data { |
336 | u32 mapped_dst; |
337 | u8 *dst_addr; |
338 | struct page **dst_pages; |
339 | u32 dst_num_pages; |
340 | pgprot_t dst_prot; |
341 | u32 mapped_src; |
342 | u8 *src_addr; |
343 | struct page **src_pages; |
344 | u32 src_num_pages; |
345 | pgprot_t src_prot; |
346 | struct vmw_diff_cpy *diff; |
347 | }; |
348 | |
349 | /** |
350 | * vmw_bo_cpu_blit_line - Blit part of a line from one bo to another. |
351 | * |
352 | * @d: Blit data as described above. |
353 | * @dst_offset: Destination copy start offset from start of bo. |
354 | * @src_offset: Source copy start offset from start of bo. |
355 | * @bytes_to_copy: Number of bytes to copy in this line. |
356 | */ |
357 | static int vmw_bo_cpu_blit_line(struct vmw_bo_blit_line_data *d, |
358 | u32 dst_offset, |
359 | u32 src_offset, |
360 | u32 bytes_to_copy) |
361 | { |
362 | struct vmw_diff_cpy *diff = d->diff; |
363 | |
364 | while (bytes_to_copy) { |
365 | u32 copy_size = bytes_to_copy; |
366 | u32 dst_page = dst_offset >> PAGE_SHIFT; |
367 | u32 src_page = src_offset >> PAGE_SHIFT; |
368 | u32 dst_page_offset = dst_offset & ~PAGE_MASK; |
369 | u32 src_page_offset = src_offset & ~PAGE_MASK; |
370 | bool unmap_dst = d->dst_addr && dst_page != d->mapped_dst; |
371 | bool unmap_src = d->src_addr && (src_page != d->mapped_src || |
372 | unmap_dst); |
373 | |
374 | copy_size = min_t(u32, copy_size, PAGE_SIZE - dst_page_offset); |
375 | copy_size = min_t(u32, copy_size, PAGE_SIZE - src_page_offset); |
376 | |
377 | if (unmap_src) { |
378 | kunmap_atomic(d->src_addr); |
379 | d->src_addr = NULL; |
380 | } |
381 | |
382 | if (unmap_dst) { |
383 | kunmap_atomic(d->dst_addr); |
384 | d->dst_addr = NULL; |
385 | } |
386 | |
387 | if (!d->dst_addr) { |
388 | if (WARN_ON_ONCE(dst_page >= d->dst_num_pages)) |
389 | return -EINVAL; |
390 | |
391 | d->dst_addr = |
392 | kmap_atomic_prot(page: d->dst_pages[dst_page], |
393 | prot: d->dst_prot); |
394 | if (!d->dst_addr) |
395 | return -ENOMEM; |
396 | |
397 | d->mapped_dst = dst_page; |
398 | } |
399 | |
400 | if (!d->src_addr) { |
401 | if (WARN_ON_ONCE(src_page >= d->src_num_pages)) |
402 | return -EINVAL; |
403 | |
404 | d->src_addr = |
405 | kmap_atomic_prot(page: d->src_pages[src_page], |
406 | prot: d->src_prot); |
407 | if (!d->src_addr) |
408 | return -ENOMEM; |
409 | |
410 | d->mapped_src = src_page; |
411 | } |
412 | diff->do_cpy(diff, d->dst_addr + dst_page_offset, |
413 | d->src_addr + src_page_offset, copy_size); |
414 | |
415 | bytes_to_copy -= copy_size; |
416 | dst_offset += copy_size; |
417 | src_offset += copy_size; |
418 | } |
419 | |
420 | return 0; |
421 | } |
422 | |
423 | /** |
424 | * vmw_bo_cpu_blit - in-kernel cpu blit. |
425 | * |
426 | * @dst: Destination buffer object. |
427 | * @dst_offset: Destination offset of blit start in bytes. |
428 | * @dst_stride: Destination stride in bytes. |
429 | * @src: Source buffer object. |
430 | * @src_offset: Source offset of blit start in bytes. |
431 | * @src_stride: Source stride in bytes. |
432 | * @w: Width of blit. |
433 | * @h: Height of blit. |
434 | * @diff: The struct vmw_diff_cpy used to track the modified bounding box. |
435 | * return: Zero on success. Negative error value on failure. Will print out |
436 | * kernel warnings on caller bugs. |
437 | * |
438 | * Performs a CPU blit from one buffer object to another avoiding a full |
439 | * bo vmap which may exhaust- or fragment vmalloc space. |
440 | * On supported architectures (x86), we're using kmap_atomic which avoids |
441 | * cross-processor TLB- and cache flushes and may, on non-HIGHMEM systems |
442 | * reference already set-up mappings. |
443 | * |
444 | * Neither of the buffer objects may be placed in PCI memory |
445 | * (Fixed memory in TTM terminology) when using this function. |
446 | */ |
447 | int vmw_bo_cpu_blit(struct ttm_buffer_object *dst, |
448 | u32 dst_offset, u32 dst_stride, |
449 | struct ttm_buffer_object *src, |
450 | u32 src_offset, u32 src_stride, |
451 | u32 w, u32 h, |
452 | struct vmw_diff_cpy *diff) |
453 | { |
454 | struct ttm_operation_ctx ctx = { |
455 | .interruptible = false, |
456 | .no_wait_gpu = false |
457 | }; |
458 | u32 j, initial_line = dst_offset / dst_stride; |
459 | struct vmw_bo_blit_line_data d = {0}; |
460 | int ret = 0; |
461 | struct page **dst_pages = NULL; |
462 | struct page **src_pages = NULL; |
463 | |
464 | /* Buffer objects need to be either pinned or reserved: */ |
465 | if (!(dst->pin_count)) |
466 | dma_resv_assert_held(dst->base.resv); |
467 | if (!(src->pin_count)) |
468 | dma_resv_assert_held(src->base.resv); |
469 | |
470 | if (!ttm_tt_is_populated(tt: dst->ttm)) { |
471 | ret = dst->bdev->funcs->ttm_tt_populate(dst->bdev, dst->ttm, &ctx); |
472 | if (ret) |
473 | return ret; |
474 | } |
475 | |
476 | if (!ttm_tt_is_populated(tt: src->ttm)) { |
477 | ret = src->bdev->funcs->ttm_tt_populate(src->bdev, src->ttm, &ctx); |
478 | if (ret) |
479 | return ret; |
480 | } |
481 | |
482 | if (!src->ttm->pages && src->ttm->sg) { |
483 | src_pages = kvmalloc_array(n: src->ttm->num_pages, |
484 | size: sizeof(struct page *), GFP_KERNEL); |
485 | if (!src_pages) |
486 | return -ENOMEM; |
487 | ret = drm_prime_sg_to_page_array(sgt: src->ttm->sg, pages: src_pages, |
488 | max_pages: src->ttm->num_pages); |
489 | if (ret) |
490 | goto out; |
491 | } |
492 | if (!dst->ttm->pages && dst->ttm->sg) { |
493 | dst_pages = kvmalloc_array(n: dst->ttm->num_pages, |
494 | size: sizeof(struct page *), GFP_KERNEL); |
495 | if (!dst_pages) { |
496 | ret = -ENOMEM; |
497 | goto out; |
498 | } |
499 | ret = drm_prime_sg_to_page_array(sgt: dst->ttm->sg, pages: dst_pages, |
500 | max_pages: dst->ttm->num_pages); |
501 | if (ret) |
502 | goto out; |
503 | } |
504 | |
505 | d.mapped_dst = 0; |
506 | d.mapped_src = 0; |
507 | d.dst_addr = NULL; |
508 | d.src_addr = NULL; |
509 | d.dst_pages = dst->ttm->pages ? dst->ttm->pages : dst_pages; |
510 | d.src_pages = src->ttm->pages ? src->ttm->pages : src_pages; |
511 | d.dst_num_pages = PFN_UP(dst->resource->size); |
512 | d.src_num_pages = PFN_UP(src->resource->size); |
513 | d.dst_prot = ttm_io_prot(bo: dst, res: dst->resource, PAGE_KERNEL); |
514 | d.src_prot = ttm_io_prot(bo: src, res: src->resource, PAGE_KERNEL); |
515 | d.diff = diff; |
516 | |
517 | for (j = 0; j < h; ++j) { |
518 | diff->line = j + initial_line; |
519 | diff->line_offset = dst_offset % dst_stride; |
520 | ret = vmw_bo_cpu_blit_line(d: &d, dst_offset, src_offset, bytes_to_copy: w); |
521 | if (ret) |
522 | goto out; |
523 | |
524 | dst_offset += dst_stride; |
525 | src_offset += src_stride; |
526 | } |
527 | out: |
528 | if (d.src_addr) |
529 | kunmap_atomic(d.src_addr); |
530 | if (d.dst_addr) |
531 | kunmap_atomic(d.dst_addr); |
532 | if (src_pages) |
533 | kvfree(addr: src_pages); |
534 | if (dst_pages) |
535 | kvfree(addr: dst_pages); |
536 | |
537 | return ret; |
538 | } |
539 | |