1
2
3
4
5
6
7
8
9#include <linux/kernel.h>
10#include <linux/slab.h>
11#include <linux/export.h>
12#include <linux/iommu-helper.h>
13#include <linux/dma-map-ops.h>
14#include <linux/vmalloc.h>
15#include <linux/pci.h>
16#include <asm/pci_dma.h>
17
18static struct kmem_cache *dma_region_table_cache;
19static struct kmem_cache *dma_page_table_cache;
20static int s390_iommu_strict;
21static u64 s390_iommu_aperture;
22static u32 s390_iommu_aperture_factor = 1;
23
24static int zpci_refresh_global(struct zpci_dev *zdev)
25{
26 return zpci_refresh_trans((u64) zdev->fh << 32, zdev->start_dma,
27 zdev->iommu_pages * PAGE_SIZE);
28}
29
30unsigned long *dma_alloc_cpu_table(void)
31{
32 unsigned long *table, *entry;
33
34 table = kmem_cache_alloc(dma_region_table_cache, GFP_ATOMIC);
35 if (!table)
36 return NULL;
37
38 for (entry = table; entry < table + ZPCI_TABLE_ENTRIES; entry++)
39 *entry = ZPCI_TABLE_INVALID;
40 return table;
41}
42
43static void dma_free_cpu_table(void *table)
44{
45 kmem_cache_free(dma_region_table_cache, table);
46}
47
48static unsigned long *dma_alloc_page_table(void)
49{
50 unsigned long *table, *entry;
51
52 table = kmem_cache_alloc(dma_page_table_cache, GFP_ATOMIC);
53 if (!table)
54 return NULL;
55
56 for (entry = table; entry < table + ZPCI_PT_ENTRIES; entry++)
57 *entry = ZPCI_PTE_INVALID;
58 return table;
59}
60
61static void dma_free_page_table(void *table)
62{
63 kmem_cache_free(dma_page_table_cache, table);
64}
65
66static unsigned long *dma_get_seg_table_origin(unsigned long *entry)
67{
68 unsigned long *sto;
69
70 if (reg_entry_isvalid(*entry))
71 sto = get_rt_sto(*entry);
72 else {
73 sto = dma_alloc_cpu_table();
74 if (!sto)
75 return NULL;
76
77 set_rt_sto(entry, sto);
78 validate_rt_entry(entry);
79 entry_clr_protected(entry);
80 }
81 return sto;
82}
83
84static unsigned long *dma_get_page_table_origin(unsigned long *entry)
85{
86 unsigned long *pto;
87
88 if (reg_entry_isvalid(*entry))
89 pto = get_st_pto(*entry);
90 else {
91 pto = dma_alloc_page_table();
92 if (!pto)
93 return NULL;
94 set_st_pto(entry, pto);
95 validate_st_entry(entry);
96 entry_clr_protected(entry);
97 }
98 return pto;
99}
100
101unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr)
102{
103 unsigned long *sto, *pto;
104 unsigned int rtx, sx, px;
105
106 rtx = calc_rtx(dma_addr);
107 sto = dma_get_seg_table_origin(&rto[rtx]);
108 if (!sto)
109 return NULL;
110
111 sx = calc_sx(dma_addr);
112 pto = dma_get_page_table_origin(&sto[sx]);
113 if (!pto)
114 return NULL;
115
116 px = calc_px(dma_addr);
117 return &pto[px];
118}
119
120void dma_update_cpu_trans(unsigned long *entry, void *page_addr, int flags)
121{
122 if (flags & ZPCI_PTE_INVALID) {
123 invalidate_pt_entry(entry);
124 } else {
125 set_pt_pfaa(entry, page_addr);
126 validate_pt_entry(entry);
127 }
128
129 if (flags & ZPCI_TABLE_PROTECTED)
130 entry_set_protected(entry);
131 else
132 entry_clr_protected(entry);
133}
134
135static int __dma_update_trans(struct zpci_dev *zdev, unsigned long pa,
136 dma_addr_t dma_addr, size_t size, int flags)
137{
138 unsigned int nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
139 u8 *page_addr = (u8 *) (pa & PAGE_MASK);
140 unsigned long irq_flags;
141 unsigned long *entry;
142 int i, rc = 0;
143
144 if (!nr_pages)
145 return -EINVAL;
146
147 spin_lock_irqsave(&zdev->dma_table_lock, irq_flags);
148 if (!zdev->dma_table) {
149 rc = -EINVAL;
150 goto out_unlock;
151 }
152
153 for (i = 0; i < nr_pages; i++) {
154 entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
155 if (!entry) {
156 rc = -ENOMEM;
157 goto undo_cpu_trans;
158 }
159 dma_update_cpu_trans(entry, page_addr, flags);
160 page_addr += PAGE_SIZE;
161 dma_addr += PAGE_SIZE;
162 }
163
164undo_cpu_trans:
165 if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID)) {
166 flags = ZPCI_PTE_INVALID;
167 while (i-- > 0) {
168 page_addr -= PAGE_SIZE;
169 dma_addr -= PAGE_SIZE;
170 entry = dma_walk_cpu_trans(zdev->dma_table, dma_addr);
171 if (!entry)
172 break;
173 dma_update_cpu_trans(entry, page_addr, flags);
174 }
175 }
176out_unlock:
177 spin_unlock_irqrestore(&zdev->dma_table_lock, irq_flags);
178 return rc;
179}
180
181static int __dma_purge_tlb(struct zpci_dev *zdev, dma_addr_t dma_addr,
182 size_t size, int flags)
183{
184 unsigned long irqflags;
185 int ret;
186
187
188
189
190
191
192
193
194 if ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID) {
195 if (!zdev->tlb_refresh)
196 return 0;
197 } else {
198 if (!s390_iommu_strict)
199 return 0;
200 }
201
202 ret = zpci_refresh_trans((u64) zdev->fh << 32, dma_addr,
203 PAGE_ALIGN(size));
204 if (ret == -ENOMEM && !s390_iommu_strict) {
205
206 if (zpci_refresh_global(zdev))
207 goto out;
208
209 spin_lock_irqsave(&zdev->iommu_bitmap_lock, irqflags);
210 bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
211 zdev->lazy_bitmap, zdev->iommu_pages);
212 bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
213 spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, irqflags);
214 ret = 0;
215 }
216out:
217 return ret;
218}
219
220static int dma_update_trans(struct zpci_dev *zdev, unsigned long pa,
221 dma_addr_t dma_addr, size_t size, int flags)
222{
223 int rc;
224
225 rc = __dma_update_trans(zdev, pa, dma_addr, size, flags);
226 if (rc)
227 return rc;
228
229 rc = __dma_purge_tlb(zdev, dma_addr, size, flags);
230 if (rc && ((flags & ZPCI_PTE_VALID_MASK) == ZPCI_PTE_VALID))
231 __dma_update_trans(zdev, pa, dma_addr, size, ZPCI_PTE_INVALID);
232
233 return rc;
234}
235
236void dma_free_seg_table(unsigned long entry)
237{
238 unsigned long *sto = get_rt_sto(entry);
239 int sx;
240
241 for (sx = 0; sx < ZPCI_TABLE_ENTRIES; sx++)
242 if (reg_entry_isvalid(sto[sx]))
243 dma_free_page_table(get_st_pto(sto[sx]));
244
245 dma_free_cpu_table(sto);
246}
247
248void dma_cleanup_tables(unsigned long *table)
249{
250 int rtx;
251
252 if (!table)
253 return;
254
255 for (rtx = 0; rtx < ZPCI_TABLE_ENTRIES; rtx++)
256 if (reg_entry_isvalid(table[rtx]))
257 dma_free_seg_table(table[rtx]);
258
259 dma_free_cpu_table(table);
260}
261
262static unsigned long __dma_alloc_iommu(struct device *dev,
263 unsigned long start, int size)
264{
265 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
266
267 return iommu_area_alloc(zdev->iommu_bitmap, zdev->iommu_pages,
268 start, size, zdev->start_dma >> PAGE_SHIFT,
269 dma_get_seg_boundary_nr_pages(dev, PAGE_SHIFT),
270 0);
271}
272
273static dma_addr_t dma_alloc_address(struct device *dev, int size)
274{
275 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
276 unsigned long offset, flags;
277
278 spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
279 offset = __dma_alloc_iommu(dev, zdev->next_bit, size);
280 if (offset == -1) {
281 if (!s390_iommu_strict) {
282
283 if (zpci_refresh_global(zdev))
284 goto out_error;
285
286 bitmap_andnot(zdev->iommu_bitmap, zdev->iommu_bitmap,
287 zdev->lazy_bitmap, zdev->iommu_pages);
288 bitmap_zero(zdev->lazy_bitmap, zdev->iommu_pages);
289 }
290
291 offset = __dma_alloc_iommu(dev, 0, size);
292 if (offset == -1)
293 goto out_error;
294 }
295 zdev->next_bit = offset + size;
296 spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
297
298 return zdev->start_dma + offset * PAGE_SIZE;
299
300out_error:
301 spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
302 return DMA_MAPPING_ERROR;
303}
304
305static void dma_free_address(struct device *dev, dma_addr_t dma_addr, int size)
306{
307 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
308 unsigned long flags, offset;
309
310 offset = (dma_addr - zdev->start_dma) >> PAGE_SHIFT;
311
312 spin_lock_irqsave(&zdev->iommu_bitmap_lock, flags);
313 if (!zdev->iommu_bitmap)
314 goto out;
315
316 if (s390_iommu_strict)
317 bitmap_clear(zdev->iommu_bitmap, offset, size);
318 else
319 bitmap_set(zdev->lazy_bitmap, offset, size);
320
321out:
322 spin_unlock_irqrestore(&zdev->iommu_bitmap_lock, flags);
323}
324
325static inline void zpci_err_dma(unsigned long rc, unsigned long addr)
326{
327 struct {
328 unsigned long rc;
329 unsigned long addr;
330 } __packed data = {rc, addr};
331
332 zpci_err_hex(&data, sizeof(data));
333}
334
335static dma_addr_t s390_dma_map_pages(struct device *dev, struct page *page,
336 unsigned long offset, size_t size,
337 enum dma_data_direction direction,
338 unsigned long attrs)
339{
340 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
341 unsigned long pa = page_to_phys(page) + offset;
342 int flags = ZPCI_PTE_VALID;
343 unsigned long nr_pages;
344 dma_addr_t dma_addr;
345 int ret;
346
347
348 nr_pages = iommu_num_pages(pa, size, PAGE_SIZE);
349 dma_addr = dma_alloc_address(dev, nr_pages);
350 if (dma_addr == DMA_MAPPING_ERROR) {
351 ret = -ENOSPC;
352 goto out_err;
353 }
354
355
356 size = nr_pages * PAGE_SIZE;
357
358 if (direction == DMA_NONE || direction == DMA_TO_DEVICE)
359 flags |= ZPCI_TABLE_PROTECTED;
360
361 ret = dma_update_trans(zdev, pa, dma_addr, size, flags);
362 if (ret)
363 goto out_free;
364
365 atomic64_add(nr_pages, &zdev->mapped_pages);
366 return dma_addr + (offset & ~PAGE_MASK);
367
368out_free:
369 dma_free_address(dev, dma_addr, nr_pages);
370out_err:
371 zpci_err("map error:\n");
372 zpci_err_dma(ret, pa);
373 return DMA_MAPPING_ERROR;
374}
375
376static void s390_dma_unmap_pages(struct device *dev, dma_addr_t dma_addr,
377 size_t size, enum dma_data_direction direction,
378 unsigned long attrs)
379{
380 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
381 int npages, ret;
382
383 npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
384 dma_addr = dma_addr & PAGE_MASK;
385 ret = dma_update_trans(zdev, 0, dma_addr, npages * PAGE_SIZE,
386 ZPCI_PTE_INVALID);
387 if (ret) {
388 zpci_err("unmap error:\n");
389 zpci_err_dma(ret, dma_addr);
390 return;
391 }
392
393 atomic64_add(npages, &zdev->unmapped_pages);
394 dma_free_address(dev, dma_addr, npages);
395}
396
397static void *s390_dma_alloc(struct device *dev, size_t size,
398 dma_addr_t *dma_handle, gfp_t flag,
399 unsigned long attrs)
400{
401 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
402 struct page *page;
403 unsigned long pa;
404 dma_addr_t map;
405
406 size = PAGE_ALIGN(size);
407 page = alloc_pages(flag | __GFP_ZERO, get_order(size));
408 if (!page)
409 return NULL;
410
411 pa = page_to_phys(page);
412 map = s390_dma_map_pages(dev, page, 0, size, DMA_BIDIRECTIONAL, 0);
413 if (dma_mapping_error(dev, map)) {
414 free_pages(pa, get_order(size));
415 return NULL;
416 }
417
418 atomic64_add(size / PAGE_SIZE, &zdev->allocated_pages);
419 if (dma_handle)
420 *dma_handle = map;
421 return (void *) pa;
422}
423
424static void s390_dma_free(struct device *dev, size_t size,
425 void *pa, dma_addr_t dma_handle,
426 unsigned long attrs)
427{
428 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
429
430 size = PAGE_ALIGN(size);
431 atomic64_sub(size / PAGE_SIZE, &zdev->allocated_pages);
432 s390_dma_unmap_pages(dev, dma_handle, size, DMA_BIDIRECTIONAL, 0);
433 free_pages((unsigned long) pa, get_order(size));
434}
435
436
437static int __s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
438 size_t size, dma_addr_t *handle,
439 enum dma_data_direction dir)
440{
441 unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT;
442 struct zpci_dev *zdev = to_zpci(to_pci_dev(dev));
443 dma_addr_t dma_addr_base, dma_addr;
444 int flags = ZPCI_PTE_VALID;
445 struct scatterlist *s;
446 unsigned long pa = 0;
447 int ret;
448
449 dma_addr_base = dma_alloc_address(dev, nr_pages);
450 if (dma_addr_base == DMA_MAPPING_ERROR)
451 return -ENOMEM;
452
453 dma_addr = dma_addr_base;
454 if (dir == DMA_NONE || dir == DMA_TO_DEVICE)
455 flags |= ZPCI_TABLE_PROTECTED;
456
457 for (s = sg; dma_addr < dma_addr_base + size; s = sg_next(s)) {
458 pa = page_to_phys(sg_page(s));
459 ret = __dma_update_trans(zdev, pa, dma_addr,
460 s->offset + s->length, flags);
461 if (ret)
462 goto unmap;
463
464 dma_addr += s->offset + s->length;
465 }
466 ret = __dma_purge_tlb(zdev, dma_addr_base, size, flags);
467 if (ret)
468 goto unmap;
469
470 *handle = dma_addr_base;
471 atomic64_add(nr_pages, &zdev->mapped_pages);
472
473 return ret;
474
475unmap:
476 dma_update_trans(zdev, 0, dma_addr_base, dma_addr - dma_addr_base,
477 ZPCI_PTE_INVALID);
478 dma_free_address(dev, dma_addr_base, nr_pages);
479 zpci_err("map error:\n");
480 zpci_err_dma(ret, pa);
481 return ret;
482}
483
484static int s390_dma_map_sg(struct device *dev, struct scatterlist *sg,
485 int nr_elements, enum dma_data_direction dir,
486 unsigned long attrs)
487{
488 struct scatterlist *s = sg, *start = sg, *dma = sg;
489 unsigned int max = dma_get_max_seg_size(dev);
490 unsigned int size = s->offset + s->length;
491 unsigned int offset = s->offset;
492 int count = 0, i, ret;
493
494 for (i = 1; i < nr_elements; i++) {
495 s = sg_next(s);
496
497 s->dma_length = 0;
498
499 if (s->offset || (size & ~PAGE_MASK) ||
500 size + s->length > max) {
501 ret = __s390_dma_map_sg(dev, start, size,
502 &dma->dma_address, dir);
503 if (ret)
504 goto unmap;
505
506 dma->dma_address += offset;
507 dma->dma_length = size - offset;
508
509 size = offset = s->offset;
510 start = s;
511 dma = sg_next(dma);
512 count++;
513 }
514 size += s->length;
515 }
516 ret = __s390_dma_map_sg(dev, start, size, &dma->dma_address, dir);
517 if (ret)
518 goto unmap;
519
520 dma->dma_address += offset;
521 dma->dma_length = size - offset;
522
523 return count + 1;
524unmap:
525 for_each_sg(sg, s, count, i)
526 s390_dma_unmap_pages(dev, sg_dma_address(s), sg_dma_len(s),
527 dir, attrs);
528
529 return ret;
530}
531
532static void s390_dma_unmap_sg(struct device *dev, struct scatterlist *sg,
533 int nr_elements, enum dma_data_direction dir,
534 unsigned long attrs)
535{
536 struct scatterlist *s;
537 int i;
538
539 for_each_sg(sg, s, nr_elements, i) {
540 if (s->dma_length)
541 s390_dma_unmap_pages(dev, s->dma_address, s->dma_length,
542 dir, attrs);
543 s->dma_address = 0;
544 s->dma_length = 0;
545 }
546}
547
548int zpci_dma_init_device(struct zpci_dev *zdev)
549{
550 int rc;
551
552
553
554
555
556
557 WARN_ON(zdev->s390_domain);
558
559 spin_lock_init(&zdev->iommu_bitmap_lock);
560 spin_lock_init(&zdev->dma_table_lock);
561
562 zdev->dma_table = dma_alloc_cpu_table();
563 if (!zdev->dma_table) {
564 rc = -ENOMEM;
565 goto out;
566 }
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581 zdev->start_dma = PAGE_ALIGN(zdev->start_dma);
582 zdev->iommu_size = min3(s390_iommu_aperture,
583 ZPCI_TABLE_SIZE_RT - zdev->start_dma,
584 zdev->end_dma - zdev->start_dma + 1);
585 zdev->end_dma = zdev->start_dma + zdev->iommu_size - 1;
586 zdev->iommu_pages = zdev->iommu_size >> PAGE_SHIFT;
587 zdev->iommu_bitmap = vzalloc(zdev->iommu_pages / 8);
588 if (!zdev->iommu_bitmap) {
589 rc = -ENOMEM;
590 goto free_dma_table;
591 }
592 if (!s390_iommu_strict) {
593 zdev->lazy_bitmap = vzalloc(zdev->iommu_pages / 8);
594 if (!zdev->lazy_bitmap) {
595 rc = -ENOMEM;
596 goto free_bitmap;
597 }
598
599 }
600 if (zpci_register_ioat(zdev, 0, zdev->start_dma, zdev->end_dma,
601 (u64)zdev->dma_table)) {
602 rc = -EIO;
603 goto free_bitmap;
604 }
605
606 return 0;
607free_bitmap:
608 vfree(zdev->iommu_bitmap);
609 zdev->iommu_bitmap = NULL;
610 vfree(zdev->lazy_bitmap);
611 zdev->lazy_bitmap = NULL;
612free_dma_table:
613 dma_free_cpu_table(zdev->dma_table);
614 zdev->dma_table = NULL;
615out:
616 return rc;
617}
618
619int zpci_dma_exit_device(struct zpci_dev *zdev)
620{
621 int cc = 0;
622
623
624
625
626
627
628 WARN_ON(zdev->s390_domain);
629 if (zdev_enabled(zdev))
630 cc = zpci_unregister_ioat(zdev, 0);
631
632
633
634
635
636 if (cc && cc != 3)
637 return -EIO;
638
639 dma_cleanup_tables(zdev->dma_table);
640 zdev->dma_table = NULL;
641 vfree(zdev->iommu_bitmap);
642 zdev->iommu_bitmap = NULL;
643 vfree(zdev->lazy_bitmap);
644 zdev->lazy_bitmap = NULL;
645 zdev->next_bit = 0;
646 return 0;
647}
648
649static int __init dma_alloc_cpu_table_caches(void)
650{
651 dma_region_table_cache = kmem_cache_create("PCI_DMA_region_tables",
652 ZPCI_TABLE_SIZE, ZPCI_TABLE_ALIGN,
653 0, NULL);
654 if (!dma_region_table_cache)
655 return -ENOMEM;
656
657 dma_page_table_cache = kmem_cache_create("PCI_DMA_page_tables",
658 ZPCI_PT_SIZE, ZPCI_PT_ALIGN,
659 0, NULL);
660 if (!dma_page_table_cache) {
661 kmem_cache_destroy(dma_region_table_cache);
662 return -ENOMEM;
663 }
664 return 0;
665}
666
667int __init zpci_dma_init(void)
668{
669 s390_iommu_aperture = (u64)high_memory;
670 if (!s390_iommu_aperture_factor)
671 s390_iommu_aperture = ULONG_MAX;
672 else
673 s390_iommu_aperture *= s390_iommu_aperture_factor;
674
675 return dma_alloc_cpu_table_caches();
676}
677
678void zpci_dma_exit(void)
679{
680 kmem_cache_destroy(dma_page_table_cache);
681 kmem_cache_destroy(dma_region_table_cache);
682}
683
684const struct dma_map_ops s390_pci_dma_ops = {
685 .alloc = s390_dma_alloc,
686 .free = s390_dma_free,
687 .map_sg = s390_dma_map_sg,
688 .unmap_sg = s390_dma_unmap_sg,
689 .map_page = s390_dma_map_pages,
690 .unmap_page = s390_dma_unmap_pages,
691 .mmap = dma_common_mmap,
692 .get_sgtable = dma_common_get_sgtable,
693 .alloc_pages = dma_common_alloc_pages,
694 .free_pages = dma_common_free_pages,
695
696};
697EXPORT_SYMBOL_GPL(s390_pci_dma_ops);
698
699static int __init s390_iommu_setup(char *str)
700{
701 if (!strcmp(str, "strict"))
702 s390_iommu_strict = 1;
703 return 1;
704}
705
706__setup("s390_iommu=", s390_iommu_setup);
707
708static int __init s390_iommu_aperture_setup(char *str)
709{
710 if (kstrtou32(str, 10, &s390_iommu_aperture_factor))
711 s390_iommu_aperture_factor = 1;
712 return 1;
713}
714
715__setup("s390_iommu_aperture=", s390_iommu_aperture_setup);
716