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11#include <linux/slab.h>
12#include <linux/file.h>
13#include <linux/anon_inodes.h>
14#include <linux/highmem.h>
15#include <linux/vmalloc.h>
16#include <linux/vdpa.h>
17
18#include "iova_domain.h"
19
20static int vduse_iotlb_add_range(struct vduse_iova_domain *domain,
21 u64 start, u64 last,
22 u64 addr, unsigned int perm,
23 struct file *file, u64 offset)
24{
25 struct vdpa_map_file *map_file;
26 int ret;
27
28 map_file = kmalloc(sizeof(*map_file), GFP_ATOMIC);
29 if (!map_file)
30 return -ENOMEM;
31
32 map_file->file = get_file(file);
33 map_file->offset = offset;
34
35 ret = vhost_iotlb_add_range_ctx(domain->iotlb, start, last,
36 addr, perm, map_file);
37 if (ret) {
38 fput(map_file->file);
39 kfree(map_file);
40 return ret;
41 }
42 return 0;
43}
44
45static void vduse_iotlb_del_range(struct vduse_iova_domain *domain,
46 u64 start, u64 last)
47{
48 struct vdpa_map_file *map_file;
49 struct vhost_iotlb_map *map;
50
51 while ((map = vhost_iotlb_itree_first(domain->iotlb, start, last))) {
52 map_file = (struct vdpa_map_file *)map->opaque;
53 fput(map_file->file);
54 kfree(map_file);
55 vhost_iotlb_map_free(domain->iotlb, map);
56 }
57}
58
59int vduse_domain_set_map(struct vduse_iova_domain *domain,
60 struct vhost_iotlb *iotlb)
61{
62 struct vdpa_map_file *map_file;
63 struct vhost_iotlb_map *map;
64 u64 start = 0ULL, last = ULLONG_MAX;
65 int ret;
66
67 spin_lock(&domain->iotlb_lock);
68 vduse_iotlb_del_range(domain, start, last);
69
70 for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
71 map = vhost_iotlb_itree_next(map, start, last)) {
72 map_file = (struct vdpa_map_file *)map->opaque;
73 ret = vduse_iotlb_add_range(domain, map->start, map->last,
74 map->addr, map->perm,
75 map_file->file,
76 map_file->offset);
77 if (ret)
78 goto err;
79 }
80 spin_unlock(&domain->iotlb_lock);
81
82 return 0;
83err:
84 vduse_iotlb_del_range(domain, start, last);
85 spin_unlock(&domain->iotlb_lock);
86 return ret;
87}
88
89void vduse_domain_clear_map(struct vduse_iova_domain *domain,
90 struct vhost_iotlb *iotlb)
91{
92 struct vhost_iotlb_map *map;
93 u64 start = 0ULL, last = ULLONG_MAX;
94
95 spin_lock(&domain->iotlb_lock);
96 for (map = vhost_iotlb_itree_first(iotlb, start, last); map;
97 map = vhost_iotlb_itree_next(map, start, last)) {
98 vduse_iotlb_del_range(domain, map->start, map->last);
99 }
100 spin_unlock(&domain->iotlb_lock);
101}
102
103static int vduse_domain_map_bounce_page(struct vduse_iova_domain *domain,
104 u64 iova, u64 size, u64 paddr)
105{
106 struct vduse_bounce_map *map;
107 u64 last = iova + size - 1;
108
109 while (iova <= last) {
110 map = &domain->bounce_maps[iova >> PAGE_SHIFT];
111 if (!map->bounce_page) {
112 map->bounce_page = alloc_page(GFP_ATOMIC);
113 if (!map->bounce_page)
114 return -ENOMEM;
115 }
116 map->orig_phys = paddr;
117 paddr += PAGE_SIZE;
118 iova += PAGE_SIZE;
119 }
120 return 0;
121}
122
123static void vduse_domain_unmap_bounce_page(struct vduse_iova_domain *domain,
124 u64 iova, u64 size)
125{
126 struct vduse_bounce_map *map;
127 u64 last = iova + size - 1;
128
129 while (iova <= last) {
130 map = &domain->bounce_maps[iova >> PAGE_SHIFT];
131 map->orig_phys = INVALID_PHYS_ADDR;
132 iova += PAGE_SIZE;
133 }
134}
135
136static void do_bounce(phys_addr_t orig, void *addr, size_t size,
137 enum dma_data_direction dir)
138{
139 unsigned long pfn = PFN_DOWN(orig);
140 unsigned int offset = offset_in_page(orig);
141 char *buffer;
142 unsigned int sz = 0;
143
144 while (size) {
145 sz = min_t(size_t, PAGE_SIZE - offset, size);
146
147 buffer = kmap_atomic(pfn_to_page(pfn));
148 if (dir == DMA_TO_DEVICE)
149 memcpy(addr, buffer + offset, sz);
150 else
151 memcpy(buffer + offset, addr, sz);
152 kunmap_atomic(buffer);
153
154 size -= sz;
155 pfn++;
156 addr += sz;
157 offset = 0;
158 }
159}
160
161static void vduse_domain_bounce(struct vduse_iova_domain *domain,
162 dma_addr_t iova, size_t size,
163 enum dma_data_direction dir)
164{
165 struct vduse_bounce_map *map;
166 unsigned int offset;
167 void *addr;
168 size_t sz;
169
170 if (iova >= domain->bounce_size)
171 return;
172
173 while (size) {
174 map = &domain->bounce_maps[iova >> PAGE_SHIFT];
175 offset = offset_in_page(iova);
176 sz = min_t(size_t, PAGE_SIZE - offset, size);
177
178 if (WARN_ON(!map->bounce_page ||
179 map->orig_phys == INVALID_PHYS_ADDR))
180 return;
181
182 addr = page_address(map->bounce_page) + offset;
183 do_bounce(map->orig_phys + offset, addr, sz, dir);
184 size -= sz;
185 iova += sz;
186 }
187}
188
189static struct page *
190vduse_domain_get_coherent_page(struct vduse_iova_domain *domain, u64 iova)
191{
192 u64 start = iova & PAGE_MASK;
193 u64 last = start + PAGE_SIZE - 1;
194 struct vhost_iotlb_map *map;
195 struct page *page = NULL;
196
197 spin_lock(&domain->iotlb_lock);
198 map = vhost_iotlb_itree_first(domain->iotlb, start, last);
199 if (!map)
200 goto out;
201
202 page = pfn_to_page((map->addr + iova - map->start) >> PAGE_SHIFT);
203 get_page(page);
204out:
205 spin_unlock(&domain->iotlb_lock);
206
207 return page;
208}
209
210static struct page *
211vduse_domain_get_bounce_page(struct vduse_iova_domain *domain, u64 iova)
212{
213 struct vduse_bounce_map *map;
214 struct page *page = NULL;
215
216 spin_lock(&domain->iotlb_lock);
217 map = &domain->bounce_maps[iova >> PAGE_SHIFT];
218 if (!map->bounce_page)
219 goto out;
220
221 page = map->bounce_page;
222 get_page(page);
223out:
224 spin_unlock(&domain->iotlb_lock);
225
226 return page;
227}
228
229static void
230vduse_domain_free_bounce_pages(struct vduse_iova_domain *domain)
231{
232 struct vduse_bounce_map *map;
233 unsigned long pfn, bounce_pfns;
234
235 bounce_pfns = domain->bounce_size >> PAGE_SHIFT;
236
237 for (pfn = 0; pfn < bounce_pfns; pfn++) {
238 map = &domain->bounce_maps[pfn];
239 if (WARN_ON(map->orig_phys != INVALID_PHYS_ADDR))
240 continue;
241
242 if (!map->bounce_page)
243 continue;
244
245 __free_page(map->bounce_page);
246 map->bounce_page = NULL;
247 }
248}
249
250void vduse_domain_reset_bounce_map(struct vduse_iova_domain *domain)
251{
252 if (!domain->bounce_map)
253 return;
254
255 spin_lock(&domain->iotlb_lock);
256 if (!domain->bounce_map)
257 goto unlock;
258
259 vduse_iotlb_del_range(domain, 0, domain->bounce_size - 1);
260 domain->bounce_map = 0;
261unlock:
262 spin_unlock(&domain->iotlb_lock);
263}
264
265static int vduse_domain_init_bounce_map(struct vduse_iova_domain *domain)
266{
267 int ret = 0;
268
269 if (domain->bounce_map)
270 return 0;
271
272 spin_lock(&domain->iotlb_lock);
273 if (domain->bounce_map)
274 goto unlock;
275
276 ret = vduse_iotlb_add_range(domain, 0, domain->bounce_size - 1,
277 0, VHOST_MAP_RW, domain->file, 0);
278 if (ret)
279 goto unlock;
280
281 domain->bounce_map = 1;
282unlock:
283 spin_unlock(&domain->iotlb_lock);
284 return ret;
285}
286
287static dma_addr_t
288vduse_domain_alloc_iova(struct iova_domain *iovad,
289 unsigned long size, unsigned long limit)
290{
291 unsigned long shift = iova_shift(iovad);
292 unsigned long iova_len = iova_align(iovad, size) >> shift;
293 unsigned long iova_pfn;
294
295
296
297
298
299
300
301 if (iova_len < (1 << (IOVA_RANGE_CACHE_MAX_SIZE - 1)))
302 iova_len = roundup_pow_of_two(iova_len);
303 iova_pfn = alloc_iova_fast(iovad, iova_len, limit >> shift, true);
304
305 return iova_pfn << shift;
306}
307
308static void vduse_domain_free_iova(struct iova_domain *iovad,
309 dma_addr_t iova, size_t size)
310{
311 unsigned long shift = iova_shift(iovad);
312 unsigned long iova_len = iova_align(iovad, size) >> shift;
313
314 free_iova_fast(iovad, iova >> shift, iova_len);
315}
316
317dma_addr_t vduse_domain_map_page(struct vduse_iova_domain *domain,
318 struct page *page, unsigned long offset,
319 size_t size, enum dma_data_direction dir,
320 unsigned long attrs)
321{
322 struct iova_domain *iovad = &domain->stream_iovad;
323 unsigned long limit = domain->bounce_size - 1;
324 phys_addr_t pa = page_to_phys(page) + offset;
325 dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit);
326
327 if (!iova)
328 return DMA_MAPPING_ERROR;
329
330 if (vduse_domain_init_bounce_map(domain))
331 goto err;
332
333 if (vduse_domain_map_bounce_page(domain, (u64)iova, (u64)size, pa))
334 goto err;
335
336 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
337 vduse_domain_bounce(domain, iova, size, DMA_TO_DEVICE);
338
339 return iova;
340err:
341 vduse_domain_free_iova(iovad, iova, size);
342 return DMA_MAPPING_ERROR;
343}
344
345void vduse_domain_unmap_page(struct vduse_iova_domain *domain,
346 dma_addr_t dma_addr, size_t size,
347 enum dma_data_direction dir, unsigned long attrs)
348{
349 struct iova_domain *iovad = &domain->stream_iovad;
350
351 if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
352 vduse_domain_bounce(domain, dma_addr, size, DMA_FROM_DEVICE);
353
354 vduse_domain_unmap_bounce_page(domain, (u64)dma_addr, (u64)size);
355 vduse_domain_free_iova(iovad, dma_addr, size);
356}
357
358void *vduse_domain_alloc_coherent(struct vduse_iova_domain *domain,
359 size_t size, dma_addr_t *dma_addr,
360 gfp_t flag, unsigned long attrs)
361{
362 struct iova_domain *iovad = &domain->consistent_iovad;
363 unsigned long limit = domain->iova_limit;
364 dma_addr_t iova = vduse_domain_alloc_iova(iovad, size, limit);
365 void *orig = alloc_pages_exact(size, flag);
366
367 if (!iova || !orig)
368 goto err;
369
370 spin_lock(&domain->iotlb_lock);
371 if (vduse_iotlb_add_range(domain, (u64)iova, (u64)iova + size - 1,
372 virt_to_phys(orig), VHOST_MAP_RW,
373 domain->file, (u64)iova)) {
374 spin_unlock(&domain->iotlb_lock);
375 goto err;
376 }
377 spin_unlock(&domain->iotlb_lock);
378
379 *dma_addr = iova;
380
381 return orig;
382err:
383 *dma_addr = DMA_MAPPING_ERROR;
384 if (orig)
385 free_pages_exact(orig, size);
386 if (iova)
387 vduse_domain_free_iova(iovad, iova, size);
388
389 return NULL;
390}
391
392void vduse_domain_free_coherent(struct vduse_iova_domain *domain, size_t size,
393 void *vaddr, dma_addr_t dma_addr,
394 unsigned long attrs)
395{
396 struct iova_domain *iovad = &domain->consistent_iovad;
397 struct vhost_iotlb_map *map;
398 struct vdpa_map_file *map_file;
399 phys_addr_t pa;
400
401 spin_lock(&domain->iotlb_lock);
402 map = vhost_iotlb_itree_first(domain->iotlb, (u64)dma_addr,
403 (u64)dma_addr + size - 1);
404 if (WARN_ON(!map)) {
405 spin_unlock(&domain->iotlb_lock);
406 return;
407 }
408 map_file = (struct vdpa_map_file *)map->opaque;
409 fput(map_file->file);
410 kfree(map_file);
411 pa = map->addr;
412 vhost_iotlb_map_free(domain->iotlb, map);
413 spin_unlock(&domain->iotlb_lock);
414
415 vduse_domain_free_iova(iovad, dma_addr, size);
416 free_pages_exact(phys_to_virt(pa), size);
417}
418
419static vm_fault_t vduse_domain_mmap_fault(struct vm_fault *vmf)
420{
421 struct vduse_iova_domain *domain = vmf->vma->vm_private_data;
422 unsigned long iova = vmf->pgoff << PAGE_SHIFT;
423 struct page *page;
424
425 if (!domain)
426 return VM_FAULT_SIGBUS;
427
428 if (iova < domain->bounce_size)
429 page = vduse_domain_get_bounce_page(domain, iova);
430 else
431 page = vduse_domain_get_coherent_page(domain, iova);
432
433 if (!page)
434 return VM_FAULT_SIGBUS;
435
436 vmf->page = page;
437
438 return 0;
439}
440
441static const struct vm_operations_struct vduse_domain_mmap_ops = {
442 .fault = vduse_domain_mmap_fault,
443};
444
445static int vduse_domain_mmap(struct file *file, struct vm_area_struct *vma)
446{
447 struct vduse_iova_domain *domain = file->private_data;
448
449 vma->vm_flags |= VM_DONTDUMP | VM_DONTEXPAND;
450 vma->vm_private_data = domain;
451 vma->vm_ops = &vduse_domain_mmap_ops;
452
453 return 0;
454}
455
456static int vduse_domain_release(struct inode *inode, struct file *file)
457{
458 struct vduse_iova_domain *domain = file->private_data;
459
460 spin_lock(&domain->iotlb_lock);
461 vduse_iotlb_del_range(domain, 0, ULLONG_MAX);
462 vduse_domain_free_bounce_pages(domain);
463 spin_unlock(&domain->iotlb_lock);
464 put_iova_domain(&domain->stream_iovad);
465 put_iova_domain(&domain->consistent_iovad);
466 vhost_iotlb_free(domain->iotlb);
467 vfree(domain->bounce_maps);
468 kfree(domain);
469
470 return 0;
471}
472
473static const struct file_operations vduse_domain_fops = {
474 .owner = THIS_MODULE,
475 .mmap = vduse_domain_mmap,
476 .release = vduse_domain_release,
477};
478
479void vduse_domain_destroy(struct vduse_iova_domain *domain)
480{
481 fput(domain->file);
482}
483
484struct vduse_iova_domain *
485vduse_domain_create(unsigned long iova_limit, size_t bounce_size)
486{
487 struct vduse_iova_domain *domain;
488 struct file *file;
489 struct vduse_bounce_map *map;
490 unsigned long pfn, bounce_pfns;
491
492 bounce_pfns = PAGE_ALIGN(bounce_size) >> PAGE_SHIFT;
493 if (iova_limit <= bounce_size)
494 return NULL;
495
496 domain = kzalloc(sizeof(*domain), GFP_KERNEL);
497 if (!domain)
498 return NULL;
499
500 domain->iotlb = vhost_iotlb_alloc(0, 0);
501 if (!domain->iotlb)
502 goto err_iotlb;
503
504 domain->iova_limit = iova_limit;
505 domain->bounce_size = PAGE_ALIGN(bounce_size);
506 domain->bounce_maps = vzalloc(bounce_pfns *
507 sizeof(struct vduse_bounce_map));
508 if (!domain->bounce_maps)
509 goto err_map;
510
511 for (pfn = 0; pfn < bounce_pfns; pfn++) {
512 map = &domain->bounce_maps[pfn];
513 map->orig_phys = INVALID_PHYS_ADDR;
514 }
515 file = anon_inode_getfile("[vduse-domain]", &vduse_domain_fops,
516 domain, O_RDWR);
517 if (IS_ERR(file))
518 goto err_file;
519
520 domain->file = file;
521 spin_lock_init(&domain->iotlb_lock);
522 init_iova_domain(&domain->stream_iovad,
523 PAGE_SIZE, IOVA_START_PFN);
524 init_iova_domain(&domain->consistent_iovad,
525 PAGE_SIZE, bounce_pfns);
526
527 return domain;
528err_file:
529 vfree(domain->bounce_maps);
530err_map:
531 vhost_iotlb_free(domain->iotlb);
532err_iotlb:
533 kfree(domain);
534 return NULL;
535}
536
537int vduse_domain_init(void)
538{
539 return iova_cache_get();
540}
541
542void vduse_domain_exit(void)
543{
544 iova_cache_put();
545}
546
