Root/
1 | /* |
2 | * Copyright 2010 |
3 | * by Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> |
4 | * |
5 | * This code provides a IOMMU for Xen PV guests with PCI passthrough. |
6 | * |
7 | * This program is free software; you can redistribute it and/or modify |
8 | * it under the terms of the GNU General Public License v2.0 as published by |
9 | * the Free Software Foundation |
10 | * |
11 | * This program is distributed in the hope that it will be useful, |
12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | * GNU General Public License for more details. |
15 | * |
16 | * PV guests under Xen are running in an non-contiguous memory architecture. |
17 | * |
18 | * When PCI pass-through is utilized, this necessitates an IOMMU for |
19 | * translating bus (DMA) to virtual and vice-versa and also providing a |
20 | * mechanism to have contiguous pages for device drivers operations (say DMA |
21 | * operations). |
22 | * |
23 | * Specifically, under Xen the Linux idea of pages is an illusion. It |
24 | * assumes that pages start at zero and go up to the available memory. To |
25 | * help with that, the Linux Xen MMU provides a lookup mechanism to |
26 | * translate the page frame numbers (PFN) to machine frame numbers (MFN) |
27 | * and vice-versa. The MFN are the "real" frame numbers. Furthermore |
28 | * memory is not contiguous. Xen hypervisor stitches memory for guests |
29 | * from different pools, which means there is no guarantee that PFN==MFN |
30 | * and PFN+1==MFN+1. Lastly with Xen 4.0, pages (in debug mode) are |
31 | * allocated in descending order (high to low), meaning the guest might |
32 | * never get any MFN's under the 4GB mark. |
33 | * |
34 | */ |
35 | |
36 | #include <linux/bootmem.h> |
37 | #include <linux/dma-mapping.h> |
38 | #include <linux/export.h> |
39 | #include <xen/swiotlb-xen.h> |
40 | #include <xen/page.h> |
41 | #include <xen/xen-ops.h> |
42 | #include <xen/hvc-console.h> |
43 | /* |
44 | * Used to do a quick range check in swiotlb_tbl_unmap_single and |
45 | * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this |
46 | * API. |
47 | */ |
48 | |
49 | static char *xen_io_tlb_start, *xen_io_tlb_end; |
50 | static unsigned long xen_io_tlb_nslabs; |
51 | /* |
52 | * Quick lookup value of the bus address of the IOTLB. |
53 | */ |
54 | |
55 | static u64 start_dma_addr; |
56 | |
57 | static dma_addr_t xen_phys_to_bus(phys_addr_t paddr) |
58 | { |
59 | return phys_to_machine(XPADDR(paddr)).maddr; |
60 | } |
61 | |
62 | static phys_addr_t xen_bus_to_phys(dma_addr_t baddr) |
63 | { |
64 | return machine_to_phys(XMADDR(baddr)).paddr; |
65 | } |
66 | |
67 | static dma_addr_t xen_virt_to_bus(void *address) |
68 | { |
69 | return xen_phys_to_bus(virt_to_phys(address)); |
70 | } |
71 | |
72 | static int check_pages_physically_contiguous(unsigned long pfn, |
73 | unsigned int offset, |
74 | size_t length) |
75 | { |
76 | unsigned long next_mfn; |
77 | int i; |
78 | int nr_pages; |
79 | |
80 | next_mfn = pfn_to_mfn(pfn); |
81 | nr_pages = (offset + length + PAGE_SIZE-1) >> PAGE_SHIFT; |
82 | |
83 | for (i = 1; i < nr_pages; i++) { |
84 | if (pfn_to_mfn(++pfn) != ++next_mfn) |
85 | return 0; |
86 | } |
87 | return 1; |
88 | } |
89 | |
90 | static int range_straddles_page_boundary(phys_addr_t p, size_t size) |
91 | { |
92 | unsigned long pfn = PFN_DOWN(p); |
93 | unsigned int offset = p & ~PAGE_MASK; |
94 | |
95 | if (offset + size <= PAGE_SIZE) |
96 | return 0; |
97 | if (check_pages_physically_contiguous(pfn, offset, size)) |
98 | return 0; |
99 | return 1; |
100 | } |
101 | |
102 | static int is_xen_swiotlb_buffer(dma_addr_t dma_addr) |
103 | { |
104 | unsigned long mfn = PFN_DOWN(dma_addr); |
105 | unsigned long pfn = mfn_to_local_pfn(mfn); |
106 | phys_addr_t paddr; |
107 | |
108 | /* If the address is outside our domain, it CAN |
109 | * have the same virtual address as another address |
110 | * in our domain. Therefore _only_ check address within our domain. |
111 | */ |
112 | if (pfn_valid(pfn)) { |
113 | paddr = PFN_PHYS(pfn); |
114 | return paddr >= virt_to_phys(xen_io_tlb_start) && |
115 | paddr < virt_to_phys(xen_io_tlb_end); |
116 | } |
117 | return 0; |
118 | } |
119 | |
120 | static int max_dma_bits = 32; |
121 | |
122 | static int |
123 | xen_swiotlb_fixup(void *buf, size_t size, unsigned long nslabs) |
124 | { |
125 | int i, rc; |
126 | int dma_bits; |
127 | |
128 | dma_bits = get_order(IO_TLB_SEGSIZE << IO_TLB_SHIFT) + PAGE_SHIFT; |
129 | |
130 | i = 0; |
131 | do { |
132 | int slabs = min(nslabs - i, (unsigned long)IO_TLB_SEGSIZE); |
133 | |
134 | do { |
135 | rc = xen_create_contiguous_region( |
136 | (unsigned long)buf + (i << IO_TLB_SHIFT), |
137 | get_order(slabs << IO_TLB_SHIFT), |
138 | dma_bits); |
139 | } while (rc && dma_bits++ < max_dma_bits); |
140 | if (rc) |
141 | return rc; |
142 | |
143 | i += slabs; |
144 | } while (i < nslabs); |
145 | return 0; |
146 | } |
147 | static unsigned long xen_set_nslabs(unsigned long nr_tbl) |
148 | { |
149 | if (!nr_tbl) { |
150 | xen_io_tlb_nslabs = (64 * 1024 * 1024 >> IO_TLB_SHIFT); |
151 | xen_io_tlb_nslabs = ALIGN(xen_io_tlb_nslabs, IO_TLB_SEGSIZE); |
152 | } else |
153 | xen_io_tlb_nslabs = nr_tbl; |
154 | |
155 | return xen_io_tlb_nslabs << IO_TLB_SHIFT; |
156 | } |
157 | |
158 | enum xen_swiotlb_err { |
159 | XEN_SWIOTLB_UNKNOWN = 0, |
160 | XEN_SWIOTLB_ENOMEM, |
161 | XEN_SWIOTLB_EFIXUP |
162 | }; |
163 | |
164 | static const char *xen_swiotlb_error(enum xen_swiotlb_err err) |
165 | { |
166 | switch (err) { |
167 | case XEN_SWIOTLB_ENOMEM: |
168 | return "Cannot allocate Xen-SWIOTLB buffer\n"; |
169 | case XEN_SWIOTLB_EFIXUP: |
170 | return "Failed to get contiguous memory for DMA from Xen!\n"\ |
171 | "You either: don't have the permissions, do not have"\ |
172 | " enough free memory under 4GB, or the hypervisor memory"\ |
173 | " is too fragmented!"; |
174 | default: |
175 | break; |
176 | } |
177 | return ""; |
178 | } |
179 | int __ref xen_swiotlb_init(int verbose, bool early) |
180 | { |
181 | unsigned long bytes, order; |
182 | int rc = -ENOMEM; |
183 | enum xen_swiotlb_err m_ret = XEN_SWIOTLB_UNKNOWN; |
184 | unsigned int repeat = 3; |
185 | |
186 | xen_io_tlb_nslabs = swiotlb_nr_tbl(); |
187 | retry: |
188 | bytes = xen_set_nslabs(xen_io_tlb_nslabs); |
189 | order = get_order(xen_io_tlb_nslabs << IO_TLB_SHIFT); |
190 | /* |
191 | * Get IO TLB memory from any location. |
192 | */ |
193 | if (early) |
194 | xen_io_tlb_start = alloc_bootmem_pages(PAGE_ALIGN(bytes)); |
195 | else { |
196 | #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) |
197 | #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) |
198 | while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { |
199 | xen_io_tlb_start = (void *)__get_free_pages(__GFP_NOWARN, order); |
200 | if (xen_io_tlb_start) |
201 | break; |
202 | order--; |
203 | } |
204 | if (order != get_order(bytes)) { |
205 | pr_warn("Warning: only able to allocate %ld MB " |
206 | "for software IO TLB\n", (PAGE_SIZE << order) >> 20); |
207 | xen_io_tlb_nslabs = SLABS_PER_PAGE << order; |
208 | bytes = xen_io_tlb_nslabs << IO_TLB_SHIFT; |
209 | } |
210 | } |
211 | if (!xen_io_tlb_start) { |
212 | m_ret = XEN_SWIOTLB_ENOMEM; |
213 | goto error; |
214 | } |
215 | xen_io_tlb_end = xen_io_tlb_start + bytes; |
216 | /* |
217 | * And replace that memory with pages under 4GB. |
218 | */ |
219 | rc = xen_swiotlb_fixup(xen_io_tlb_start, |
220 | bytes, |
221 | xen_io_tlb_nslabs); |
222 | if (rc) { |
223 | if (early) |
224 | free_bootmem(__pa(xen_io_tlb_start), PAGE_ALIGN(bytes)); |
225 | else { |
226 | free_pages((unsigned long)xen_io_tlb_start, order); |
227 | xen_io_tlb_start = NULL; |
228 | } |
229 | m_ret = XEN_SWIOTLB_EFIXUP; |
230 | goto error; |
231 | } |
232 | start_dma_addr = xen_virt_to_bus(xen_io_tlb_start); |
233 | if (early) { |
234 | if (swiotlb_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs, |
235 | verbose)) |
236 | panic("Cannot allocate SWIOTLB buffer"); |
237 | rc = 0; |
238 | } else |
239 | rc = swiotlb_late_init_with_tbl(xen_io_tlb_start, xen_io_tlb_nslabs); |
240 | return rc; |
241 | error: |
242 | if (repeat--) { |
243 | xen_io_tlb_nslabs = max(1024UL, /* Min is 2MB */ |
244 | (xen_io_tlb_nslabs >> 1)); |
245 | printk(KERN_INFO "Xen-SWIOTLB: Lowering to %luMB\n", |
246 | (xen_io_tlb_nslabs << IO_TLB_SHIFT) >> 20); |
247 | goto retry; |
248 | } |
249 | pr_err("%s (rc:%d)", xen_swiotlb_error(m_ret), rc); |
250 | if (early) |
251 | panic("%s (rc:%d)", xen_swiotlb_error(m_ret), rc); |
252 | else |
253 | free_pages((unsigned long)xen_io_tlb_start, order); |
254 | return rc; |
255 | } |
256 | void * |
257 | xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size, |
258 | dma_addr_t *dma_handle, gfp_t flags, |
259 | struct dma_attrs *attrs) |
260 | { |
261 | void *ret; |
262 | int order = get_order(size); |
263 | u64 dma_mask = DMA_BIT_MASK(32); |
264 | unsigned long vstart; |
265 | phys_addr_t phys; |
266 | dma_addr_t dev_addr; |
267 | |
268 | /* |
269 | * Ignore region specifiers - the kernel's ideas of |
270 | * pseudo-phys memory layout has nothing to do with the |
271 | * machine physical layout. We can't allocate highmem |
272 | * because we can't return a pointer to it. |
273 | */ |
274 | flags &= ~(__GFP_DMA | __GFP_HIGHMEM); |
275 | |
276 | if (dma_alloc_from_coherent(hwdev, size, dma_handle, &ret)) |
277 | return ret; |
278 | |
279 | vstart = __get_free_pages(flags, order); |
280 | ret = (void *)vstart; |
281 | |
282 | if (!ret) |
283 | return ret; |
284 | |
285 | if (hwdev && hwdev->coherent_dma_mask) |
286 | dma_mask = dma_alloc_coherent_mask(hwdev, flags); |
287 | |
288 | phys = virt_to_phys(ret); |
289 | dev_addr = xen_phys_to_bus(phys); |
290 | if (((dev_addr + size - 1 <= dma_mask)) && |
291 | !range_straddles_page_boundary(phys, size)) |
292 | *dma_handle = dev_addr; |
293 | else { |
294 | if (xen_create_contiguous_region(vstart, order, |
295 | fls64(dma_mask)) != 0) { |
296 | free_pages(vstart, order); |
297 | return NULL; |
298 | } |
299 | *dma_handle = virt_to_machine(ret).maddr; |
300 | } |
301 | memset(ret, 0, size); |
302 | return ret; |
303 | } |
304 | EXPORT_SYMBOL_GPL(xen_swiotlb_alloc_coherent); |
305 | |
306 | void |
307 | xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, |
308 | dma_addr_t dev_addr, struct dma_attrs *attrs) |
309 | { |
310 | int order = get_order(size); |
311 | phys_addr_t phys; |
312 | u64 dma_mask = DMA_BIT_MASK(32); |
313 | |
314 | if (dma_release_from_coherent(hwdev, order, vaddr)) |
315 | return; |
316 | |
317 | if (hwdev && hwdev->coherent_dma_mask) |
318 | dma_mask = hwdev->coherent_dma_mask; |
319 | |
320 | phys = virt_to_phys(vaddr); |
321 | |
322 | if (((dev_addr + size - 1 > dma_mask)) || |
323 | range_straddles_page_boundary(phys, size)) |
324 | xen_destroy_contiguous_region((unsigned long)vaddr, order); |
325 | |
326 | free_pages((unsigned long)vaddr, order); |
327 | } |
328 | EXPORT_SYMBOL_GPL(xen_swiotlb_free_coherent); |
329 | |
330 | |
331 | /* |
332 | * Map a single buffer of the indicated size for DMA in streaming mode. The |
333 | * physical address to use is returned. |
334 | * |
335 | * Once the device is given the dma address, the device owns this memory until |
336 | * either xen_swiotlb_unmap_page or xen_swiotlb_dma_sync_single is performed. |
337 | */ |
338 | dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, |
339 | unsigned long offset, size_t size, |
340 | enum dma_data_direction dir, |
341 | struct dma_attrs *attrs) |
342 | { |
343 | phys_addr_t map, phys = page_to_phys(page) + offset; |
344 | dma_addr_t dev_addr = xen_phys_to_bus(phys); |
345 | |
346 | BUG_ON(dir == DMA_NONE); |
347 | /* |
348 | * If the address happens to be in the device's DMA window, |
349 | * we can safely return the device addr and not worry about bounce |
350 | * buffering it. |
351 | */ |
352 | if (dma_capable(dev, dev_addr, size) && |
353 | !range_straddles_page_boundary(phys, size) && !swiotlb_force) |
354 | return dev_addr; |
355 | |
356 | /* |
357 | * Oh well, have to allocate and map a bounce buffer. |
358 | */ |
359 | map = swiotlb_tbl_map_single(dev, start_dma_addr, phys, size, dir); |
360 | if (map == SWIOTLB_MAP_ERROR) |
361 | return DMA_ERROR_CODE; |
362 | |
363 | dev_addr = xen_phys_to_bus(map); |
364 | |
365 | /* |
366 | * Ensure that the address returned is DMA'ble |
367 | */ |
368 | if (!dma_capable(dev, dev_addr, size)) { |
369 | swiotlb_tbl_unmap_single(dev, map, size, dir); |
370 | dev_addr = 0; |
371 | } |
372 | return dev_addr; |
373 | } |
374 | EXPORT_SYMBOL_GPL(xen_swiotlb_map_page); |
375 | |
376 | /* |
377 | * Unmap a single streaming mode DMA translation. The dma_addr and size must |
378 | * match what was provided for in a previous xen_swiotlb_map_page call. All |
379 | * other usages are undefined. |
380 | * |
381 | * After this call, reads by the cpu to the buffer are guaranteed to see |
382 | * whatever the device wrote there. |
383 | */ |
384 | static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr, |
385 | size_t size, enum dma_data_direction dir) |
386 | { |
387 | phys_addr_t paddr = xen_bus_to_phys(dev_addr); |
388 | |
389 | BUG_ON(dir == DMA_NONE); |
390 | |
391 | /* NOTE: We use dev_addr here, not paddr! */ |
392 | if (is_xen_swiotlb_buffer(dev_addr)) { |
393 | swiotlb_tbl_unmap_single(hwdev, paddr, size, dir); |
394 | return; |
395 | } |
396 | |
397 | if (dir != DMA_FROM_DEVICE) |
398 | return; |
399 | |
400 | /* |
401 | * phys_to_virt doesn't work with hihgmem page but we could |
402 | * call dma_mark_clean() with hihgmem page here. However, we |
403 | * are fine since dma_mark_clean() is null on POWERPC. We can |
404 | * make dma_mark_clean() take a physical address if necessary. |
405 | */ |
406 | dma_mark_clean(phys_to_virt(paddr), size); |
407 | } |
408 | |
409 | void xen_swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr, |
410 | size_t size, enum dma_data_direction dir, |
411 | struct dma_attrs *attrs) |
412 | { |
413 | xen_unmap_single(hwdev, dev_addr, size, dir); |
414 | } |
415 | EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_page); |
416 | |
417 | /* |
418 | * Make physical memory consistent for a single streaming mode DMA translation |
419 | * after a transfer. |
420 | * |
421 | * If you perform a xen_swiotlb_map_page() but wish to interrogate the buffer |
422 | * using the cpu, yet do not wish to teardown the dma mapping, you must |
423 | * call this function before doing so. At the next point you give the dma |
424 | * address back to the card, you must first perform a |
425 | * xen_swiotlb_dma_sync_for_device, and then the device again owns the buffer |
426 | */ |
427 | static void |
428 | xen_swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, |
429 | size_t size, enum dma_data_direction dir, |
430 | enum dma_sync_target target) |
431 | { |
432 | phys_addr_t paddr = xen_bus_to_phys(dev_addr); |
433 | |
434 | BUG_ON(dir == DMA_NONE); |
435 | |
436 | /* NOTE: We use dev_addr here, not paddr! */ |
437 | if (is_xen_swiotlb_buffer(dev_addr)) { |
438 | swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target); |
439 | return; |
440 | } |
441 | |
442 | if (dir != DMA_FROM_DEVICE) |
443 | return; |
444 | |
445 | dma_mark_clean(phys_to_virt(paddr), size); |
446 | } |
447 | |
448 | void |
449 | xen_swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr, |
450 | size_t size, enum dma_data_direction dir) |
451 | { |
452 | xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU); |
453 | } |
454 | EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_cpu); |
455 | |
456 | void |
457 | xen_swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, |
458 | size_t size, enum dma_data_direction dir) |
459 | { |
460 | xen_swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE); |
461 | } |
462 | EXPORT_SYMBOL_GPL(xen_swiotlb_sync_single_for_device); |
463 | |
464 | /* |
465 | * Map a set of buffers described by scatterlist in streaming mode for DMA. |
466 | * This is the scatter-gather version of the above xen_swiotlb_map_page |
467 | * interface. Here the scatter gather list elements are each tagged with the |
468 | * appropriate dma address and length. They are obtained via |
469 | * sg_dma_{address,length}(SG). |
470 | * |
471 | * NOTE: An implementation may be able to use a smaller number of |
472 | * DMA address/length pairs than there are SG table elements. |
473 | * (for example via virtual mapping capabilities) |
474 | * The routine returns the number of addr/length pairs actually |
475 | * used, at most nents. |
476 | * |
477 | * Device ownership issues as mentioned above for xen_swiotlb_map_page are the |
478 | * same here. |
479 | */ |
480 | int |
481 | xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, |
482 | int nelems, enum dma_data_direction dir, |
483 | struct dma_attrs *attrs) |
484 | { |
485 | struct scatterlist *sg; |
486 | int i; |
487 | |
488 | BUG_ON(dir == DMA_NONE); |
489 | |
490 | for_each_sg(sgl, sg, nelems, i) { |
491 | phys_addr_t paddr = sg_phys(sg); |
492 | dma_addr_t dev_addr = xen_phys_to_bus(paddr); |
493 | |
494 | if (swiotlb_force || |
495 | !dma_capable(hwdev, dev_addr, sg->length) || |
496 | range_straddles_page_boundary(paddr, sg->length)) { |
497 | phys_addr_t map = swiotlb_tbl_map_single(hwdev, |
498 | start_dma_addr, |
499 | sg_phys(sg), |
500 | sg->length, |
501 | dir); |
502 | if (map == SWIOTLB_MAP_ERROR) { |
503 | /* Don't panic here, we expect map_sg users |
504 | to do proper error handling. */ |
505 | xen_swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir, |
506 | attrs); |
507 | sgl[0].dma_length = 0; |
508 | return DMA_ERROR_CODE; |
509 | } |
510 | sg->dma_address = xen_phys_to_bus(map); |
511 | } else |
512 | sg->dma_address = dev_addr; |
513 | sg->dma_length = sg->length; |
514 | } |
515 | return nelems; |
516 | } |
517 | EXPORT_SYMBOL_GPL(xen_swiotlb_map_sg_attrs); |
518 | |
519 | /* |
520 | * Unmap a set of streaming mode DMA translations. Again, cpu read rules |
521 | * concerning calls here are the same as for swiotlb_unmap_page() above. |
522 | */ |
523 | void |
524 | xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, |
525 | int nelems, enum dma_data_direction dir, |
526 | struct dma_attrs *attrs) |
527 | { |
528 | struct scatterlist *sg; |
529 | int i; |
530 | |
531 | BUG_ON(dir == DMA_NONE); |
532 | |
533 | for_each_sg(sgl, sg, nelems, i) |
534 | xen_unmap_single(hwdev, sg->dma_address, sg->dma_length, dir); |
535 | |
536 | } |
537 | EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg_attrs); |
538 | |
539 | /* |
540 | * Make physical memory consistent for a set of streaming mode DMA translations |
541 | * after a transfer. |
542 | * |
543 | * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules |
544 | * and usage. |
545 | */ |
546 | static void |
547 | xen_swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl, |
548 | int nelems, enum dma_data_direction dir, |
549 | enum dma_sync_target target) |
550 | { |
551 | struct scatterlist *sg; |
552 | int i; |
553 | |
554 | for_each_sg(sgl, sg, nelems, i) |
555 | xen_swiotlb_sync_single(hwdev, sg->dma_address, |
556 | sg->dma_length, dir, target); |
557 | } |
558 | |
559 | void |
560 | xen_swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg, |
561 | int nelems, enum dma_data_direction dir) |
562 | { |
563 | xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU); |
564 | } |
565 | EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_cpu); |
566 | |
567 | void |
568 | xen_swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, |
569 | int nelems, enum dma_data_direction dir) |
570 | { |
571 | xen_swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE); |
572 | } |
573 | EXPORT_SYMBOL_GPL(xen_swiotlb_sync_sg_for_device); |
574 | |
575 | int |
576 | xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) |
577 | { |
578 | return !dma_addr; |
579 | } |
580 | EXPORT_SYMBOL_GPL(xen_swiotlb_dma_mapping_error); |
581 | |
582 | /* |
583 | * Return whether the given device DMA address mask can be supported |
584 | * properly. For example, if your device can only drive the low 24-bits |
585 | * during bus mastering, then you would pass 0x00ffffff as the mask to |
586 | * this function. |
587 | */ |
588 | int |
589 | xen_swiotlb_dma_supported(struct device *hwdev, u64 mask) |
590 | { |
591 | return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask; |
592 | } |
593 | EXPORT_SYMBOL_GPL(xen_swiotlb_dma_supported); |
594 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9