Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * Dynamic DMA mapping support. | |
3 | * | |
563aaf06 | 4 | * This implementation is a fallback for platforms that do not support |
1da177e4 LT |
5 | * I/O TLBs (aka DMA address translation hardware). |
6 | * Copyright (C) 2000 Asit Mallick <Asit.K.Mallick@intel.com> | |
7 | * Copyright (C) 2000 Goutham Rao <goutham.rao@intel.com> | |
8 | * Copyright (C) 2000, 2003 Hewlett-Packard Co | |
9 | * David Mosberger-Tang <davidm@hpl.hp.com> | |
10 | * | |
11 | * 03/05/07 davidm Switch from PCI-DMA to generic device DMA API. | |
12 | * 00/12/13 davidm Rename to swiotlb.c and add mark_clean() to avoid | |
13 | * unnecessary i-cache flushing. | |
569c8bf5 JL |
14 | * 04/07/.. ak Better overflow handling. Assorted fixes. |
15 | * 05/09/10 linville Add support for syncing ranges, support syncing for | |
16 | * DMA_BIDIRECTIONAL mappings, miscellaneous cleanup. | |
1da177e4 LT |
17 | */ |
18 | ||
19 | #include <linux/cache.h> | |
17e5ad6c | 20 | #include <linux/dma-mapping.h> |
1da177e4 LT |
21 | #include <linux/mm.h> |
22 | #include <linux/module.h> | |
1da177e4 | 23 | #include <linux/spinlock.h> |
8c5df16b | 24 | #include <linux/swiotlb.h> |
1da177e4 LT |
25 | #include <linux/string.h> |
26 | #include <linux/types.h> | |
27 | #include <linux/ctype.h> | |
ef9b1893 | 28 | #include <linux/highmem.h> |
1da177e4 LT |
29 | |
30 | #include <asm/io.h> | |
1da177e4 | 31 | #include <asm/dma.h> |
17e5ad6c | 32 | #include <asm/scatterlist.h> |
1da177e4 LT |
33 | |
34 | #include <linux/init.h> | |
35 | #include <linux/bootmem.h> | |
a8522509 | 36 | #include <linux/iommu-helper.h> |
1da177e4 LT |
37 | |
38 | #define OFFSET(val,align) ((unsigned long) \ | |
39 | ( (val) & ( (align) - 1))) | |
40 | ||
0b9afede AW |
41 | #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT)) |
42 | ||
43 | /* | |
44 | * Minimum IO TLB size to bother booting with. Systems with mainly | |
45 | * 64bit capable cards will only lightly use the swiotlb. If we can't | |
46 | * allocate a contiguous 1MB, we're probably in trouble anyway. | |
47 | */ | |
48 | #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT) | |
49 | ||
de69e0f0 JL |
50 | /* |
51 | * Enumeration for sync targets | |
52 | */ | |
53 | enum dma_sync_target { | |
54 | SYNC_FOR_CPU = 0, | |
55 | SYNC_FOR_DEVICE = 1, | |
56 | }; | |
57 | ||
1da177e4 LT |
58 | int swiotlb_force; |
59 | ||
60 | /* | |
61 | * Used to do a quick range check in swiotlb_unmap_single and | |
62 | * swiotlb_sync_single_*, to see if the memory was in fact allocated by this | |
63 | * API. | |
64 | */ | |
65 | static char *io_tlb_start, *io_tlb_end; | |
66 | ||
67 | /* | |
68 | * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and | |
69 | * io_tlb_end. This is command line adjustable via setup_io_tlb_npages. | |
70 | */ | |
71 | static unsigned long io_tlb_nslabs; | |
72 | ||
73 | /* | |
74 | * When the IOMMU overflows we return a fallback buffer. This sets the size. | |
75 | */ | |
76 | static unsigned long io_tlb_overflow = 32*1024; | |
77 | ||
78 | void *io_tlb_overflow_buffer; | |
79 | ||
80 | /* | |
81 | * This is a free list describing the number of free entries available from | |
82 | * each index | |
83 | */ | |
84 | static unsigned int *io_tlb_list; | |
85 | static unsigned int io_tlb_index; | |
86 | ||
87 | /* | |
88 | * We need to save away the original address corresponding to a mapped entry | |
89 | * for the sync operations. | |
90 | */ | |
ef9b1893 JF |
91 | static struct swiotlb_phys_addr { |
92 | struct page *page; | |
93 | unsigned int offset; | |
94 | } *io_tlb_orig_addr; | |
1da177e4 LT |
95 | |
96 | /* | |
97 | * Protect the above data structures in the map and unmap calls | |
98 | */ | |
99 | static DEFINE_SPINLOCK(io_tlb_lock); | |
100 | ||
101 | static int __init | |
102 | setup_io_tlb_npages(char *str) | |
103 | { | |
104 | if (isdigit(*str)) { | |
e8579e72 | 105 | io_tlb_nslabs = simple_strtoul(str, &str, 0); |
1da177e4 LT |
106 | /* avoid tail segment of size < IO_TLB_SEGSIZE */ |
107 | io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); | |
108 | } | |
109 | if (*str == ',') | |
110 | ++str; | |
111 | if (!strcmp(str, "force")) | |
112 | swiotlb_force = 1; | |
113 | return 1; | |
114 | } | |
115 | __setup("swiotlb=", setup_io_tlb_npages); | |
116 | /* make io_tlb_overflow tunable too? */ | |
117 | ||
79ff56eb | 118 | void * __weak __init swiotlb_alloc_boot(size_t size, unsigned long nslabs) |
8c5df16b JF |
119 | { |
120 | return alloc_bootmem_low_pages(size); | |
121 | } | |
122 | ||
123 | void * __weak swiotlb_alloc(unsigned order, unsigned long nslabs) | |
124 | { | |
125 | return (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN, order); | |
126 | } | |
127 | ||
e08e1f7a IC |
128 | dma_addr_t __weak swiotlb_phys_to_bus(phys_addr_t paddr) |
129 | { | |
130 | return paddr; | |
131 | } | |
132 | ||
133 | phys_addr_t __weak swiotlb_bus_to_phys(dma_addr_t baddr) | |
134 | { | |
135 | return baddr; | |
136 | } | |
137 | ||
138 | static dma_addr_t swiotlb_virt_to_bus(volatile void *address) | |
139 | { | |
140 | return swiotlb_phys_to_bus(virt_to_phys(address)); | |
141 | } | |
142 | ||
143 | static void *swiotlb_bus_to_virt(dma_addr_t address) | |
144 | { | |
145 | return phys_to_virt(swiotlb_bus_to_phys(address)); | |
146 | } | |
147 | ||
b81ea27b IC |
148 | int __weak swiotlb_arch_range_needs_mapping(void *ptr, size_t size) |
149 | { | |
150 | return 0; | |
151 | } | |
152 | ||
ef9b1893 JF |
153 | static dma_addr_t swiotlb_sg_to_bus(struct scatterlist *sg) |
154 | { | |
155 | return swiotlb_phys_to_bus(page_to_phys(sg_page(sg)) + sg->offset); | |
156 | } | |
157 | ||
2e5b2b86 IC |
158 | static void swiotlb_print_info(unsigned long bytes) |
159 | { | |
160 | phys_addr_t pstart, pend; | |
161 | dma_addr_t bstart, bend; | |
162 | ||
163 | pstart = virt_to_phys(io_tlb_start); | |
164 | pend = virt_to_phys(io_tlb_end); | |
165 | ||
166 | bstart = swiotlb_phys_to_bus(pstart); | |
167 | bend = swiotlb_phys_to_bus(pend); | |
168 | ||
169 | printk(KERN_INFO "Placing %luMB software IO TLB between %p - %p\n", | |
170 | bytes >> 20, io_tlb_start, io_tlb_end); | |
171 | if (pstart != bstart || pend != bend) | |
172 | printk(KERN_INFO "software IO TLB at phys %#llx - %#llx" | |
173 | " bus %#llx - %#llx\n", | |
174 | (unsigned long long)pstart, | |
175 | (unsigned long long)pend, | |
176 | (unsigned long long)bstart, | |
177 | (unsigned long long)bend); | |
178 | else | |
179 | printk(KERN_INFO "software IO TLB at phys %#llx - %#llx\n", | |
180 | (unsigned long long)pstart, | |
181 | (unsigned long long)pend); | |
182 | } | |
183 | ||
1da177e4 LT |
184 | /* |
185 | * Statically reserve bounce buffer space and initialize bounce buffer data | |
17e5ad6c | 186 | * structures for the software IO TLB used to implement the DMA API. |
1da177e4 | 187 | */ |
563aaf06 JB |
188 | void __init |
189 | swiotlb_init_with_default_size(size_t default_size) | |
1da177e4 | 190 | { |
563aaf06 | 191 | unsigned long i, bytes; |
1da177e4 LT |
192 | |
193 | if (!io_tlb_nslabs) { | |
e8579e72 | 194 | io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); |
1da177e4 LT |
195 | io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); |
196 | } | |
197 | ||
563aaf06 JB |
198 | bytes = io_tlb_nslabs << IO_TLB_SHIFT; |
199 | ||
1da177e4 LT |
200 | /* |
201 | * Get IO TLB memory from the low pages | |
202 | */ | |
8c5df16b | 203 | io_tlb_start = swiotlb_alloc_boot(bytes, io_tlb_nslabs); |
1da177e4 LT |
204 | if (!io_tlb_start) |
205 | panic("Cannot allocate SWIOTLB buffer"); | |
563aaf06 | 206 | io_tlb_end = io_tlb_start + bytes; |
1da177e4 LT |
207 | |
208 | /* | |
209 | * Allocate and initialize the free list array. This array is used | |
210 | * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE | |
211 | * between io_tlb_start and io_tlb_end. | |
212 | */ | |
213 | io_tlb_list = alloc_bootmem(io_tlb_nslabs * sizeof(int)); | |
25667d67 | 214 | for (i = 0; i < io_tlb_nslabs; i++) |
1da177e4 LT |
215 | io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); |
216 | io_tlb_index = 0; | |
ef9b1893 | 217 | io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(struct swiotlb_phys_addr)); |
1da177e4 LT |
218 | |
219 | /* | |
220 | * Get the overflow emergency buffer | |
221 | */ | |
222 | io_tlb_overflow_buffer = alloc_bootmem_low(io_tlb_overflow); | |
563aaf06 JB |
223 | if (!io_tlb_overflow_buffer) |
224 | panic("Cannot allocate SWIOTLB overflow buffer!\n"); | |
225 | ||
2e5b2b86 | 226 | swiotlb_print_info(bytes); |
1da177e4 LT |
227 | } |
228 | ||
563aaf06 JB |
229 | void __init |
230 | swiotlb_init(void) | |
1da177e4 | 231 | { |
25667d67 | 232 | swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */ |
1da177e4 LT |
233 | } |
234 | ||
0b9afede AW |
235 | /* |
236 | * Systems with larger DMA zones (those that don't support ISA) can | |
237 | * initialize the swiotlb later using the slab allocator if needed. | |
238 | * This should be just like above, but with some error catching. | |
239 | */ | |
240 | int | |
563aaf06 | 241 | swiotlb_late_init_with_default_size(size_t default_size) |
0b9afede | 242 | { |
563aaf06 | 243 | unsigned long i, bytes, req_nslabs = io_tlb_nslabs; |
0b9afede AW |
244 | unsigned int order; |
245 | ||
246 | if (!io_tlb_nslabs) { | |
247 | io_tlb_nslabs = (default_size >> IO_TLB_SHIFT); | |
248 | io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE); | |
249 | } | |
250 | ||
251 | /* | |
252 | * Get IO TLB memory from the low pages | |
253 | */ | |
563aaf06 | 254 | order = get_order(io_tlb_nslabs << IO_TLB_SHIFT); |
0b9afede | 255 | io_tlb_nslabs = SLABS_PER_PAGE << order; |
563aaf06 | 256 | bytes = io_tlb_nslabs << IO_TLB_SHIFT; |
0b9afede AW |
257 | |
258 | while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) { | |
8c5df16b | 259 | io_tlb_start = swiotlb_alloc(order, io_tlb_nslabs); |
0b9afede AW |
260 | if (io_tlb_start) |
261 | break; | |
262 | order--; | |
263 | } | |
264 | ||
265 | if (!io_tlb_start) | |
266 | goto cleanup1; | |
267 | ||
563aaf06 | 268 | if (order != get_order(bytes)) { |
0b9afede AW |
269 | printk(KERN_WARNING "Warning: only able to allocate %ld MB " |
270 | "for software IO TLB\n", (PAGE_SIZE << order) >> 20); | |
271 | io_tlb_nslabs = SLABS_PER_PAGE << order; | |
563aaf06 | 272 | bytes = io_tlb_nslabs << IO_TLB_SHIFT; |
0b9afede | 273 | } |
563aaf06 JB |
274 | io_tlb_end = io_tlb_start + bytes; |
275 | memset(io_tlb_start, 0, bytes); | |
0b9afede AW |
276 | |
277 | /* | |
278 | * Allocate and initialize the free list array. This array is used | |
279 | * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE | |
280 | * between io_tlb_start and io_tlb_end. | |
281 | */ | |
282 | io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL, | |
283 | get_order(io_tlb_nslabs * sizeof(int))); | |
284 | if (!io_tlb_list) | |
285 | goto cleanup2; | |
286 | ||
287 | for (i = 0; i < io_tlb_nslabs; i++) | |
288 | io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE); | |
289 | io_tlb_index = 0; | |
290 | ||
ef9b1893 JF |
291 | io_tlb_orig_addr = (struct swiotlb_phys_addr *)__get_free_pages(GFP_KERNEL, |
292 | get_order(io_tlb_nslabs * sizeof(struct swiotlb_phys_addr))); | |
0b9afede AW |
293 | if (!io_tlb_orig_addr) |
294 | goto cleanup3; | |
295 | ||
ef9b1893 | 296 | memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(struct swiotlb_phys_addr)); |
0b9afede AW |
297 | |
298 | /* | |
299 | * Get the overflow emergency buffer | |
300 | */ | |
301 | io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA, | |
302 | get_order(io_tlb_overflow)); | |
303 | if (!io_tlb_overflow_buffer) | |
304 | goto cleanup4; | |
305 | ||
2e5b2b86 | 306 | swiotlb_print_info(bytes); |
0b9afede AW |
307 | |
308 | return 0; | |
309 | ||
310 | cleanup4: | |
25667d67 TL |
311 | free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs * |
312 | sizeof(char *))); | |
0b9afede AW |
313 | io_tlb_orig_addr = NULL; |
314 | cleanup3: | |
25667d67 TL |
315 | free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs * |
316 | sizeof(int))); | |
0b9afede | 317 | io_tlb_list = NULL; |
0b9afede | 318 | cleanup2: |
563aaf06 | 319 | io_tlb_end = NULL; |
0b9afede AW |
320 | free_pages((unsigned long)io_tlb_start, order); |
321 | io_tlb_start = NULL; | |
322 | cleanup1: | |
323 | io_tlb_nslabs = req_nslabs; | |
324 | return -ENOMEM; | |
325 | } | |
326 | ||
be6b0267 | 327 | static int |
2797982e | 328 | address_needs_mapping(struct device *hwdev, dma_addr_t addr, size_t size) |
1da177e4 | 329 | { |
07a2c01a | 330 | return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size); |
1da177e4 LT |
331 | } |
332 | ||
b81ea27b IC |
333 | static inline int range_needs_mapping(void *ptr, size_t size) |
334 | { | |
335 | return swiotlb_force || swiotlb_arch_range_needs_mapping(ptr, size); | |
336 | } | |
337 | ||
640aebfe FT |
338 | static int is_swiotlb_buffer(char *addr) |
339 | { | |
340 | return addr >= io_tlb_start && addr < io_tlb_end; | |
341 | } | |
342 | ||
ef9b1893 | 343 | static struct swiotlb_phys_addr swiotlb_bus_to_phys_addr(char *dma_addr) |
1b548f66 | 344 | { |
ef9b1893 JF |
345 | int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT; |
346 | struct swiotlb_phys_addr buffer = io_tlb_orig_addr[index]; | |
347 | buffer.offset += (long)dma_addr & ((1 << IO_TLB_SHIFT) - 1); | |
348 | buffer.page += buffer.offset >> PAGE_SHIFT; | |
349 | buffer.offset &= PAGE_SIZE - 1; | |
350 | return buffer; | |
351 | } | |
352 | ||
353 | static void | |
354 | __sync_single(struct swiotlb_phys_addr buffer, char *dma_addr, size_t size, int dir) | |
355 | { | |
356 | if (PageHighMem(buffer.page)) { | |
357 | size_t len, bytes; | |
358 | char *dev, *host, *kmp; | |
359 | ||
360 | len = size; | |
361 | while (len != 0) { | |
362 | unsigned long flags; | |
363 | ||
364 | bytes = len; | |
365 | if ((bytes + buffer.offset) > PAGE_SIZE) | |
366 | bytes = PAGE_SIZE - buffer.offset; | |
367 | local_irq_save(flags); /* protects KM_BOUNCE_READ */ | |
368 | kmp = kmap_atomic(buffer.page, KM_BOUNCE_READ); | |
369 | dev = dma_addr + size - len; | |
370 | host = kmp + buffer.offset; | |
371 | if (dir == DMA_FROM_DEVICE) | |
372 | memcpy(host, dev, bytes); | |
373 | else | |
374 | memcpy(dev, host, bytes); | |
375 | kunmap_atomic(kmp, KM_BOUNCE_READ); | |
376 | local_irq_restore(flags); | |
377 | len -= bytes; | |
378 | buffer.page++; | |
379 | buffer.offset = 0; | |
380 | } | |
381 | } else { | |
382 | void *v = page_address(buffer.page) + buffer.offset; | |
383 | ||
384 | if (dir == DMA_TO_DEVICE) | |
385 | memcpy(dma_addr, v, size); | |
386 | else | |
387 | memcpy(v, dma_addr, size); | |
388 | } | |
1b548f66 JF |
389 | } |
390 | ||
1da177e4 LT |
391 | /* |
392 | * Allocates bounce buffer and returns its kernel virtual address. | |
393 | */ | |
394 | static void * | |
ef9b1893 | 395 | map_single(struct device *hwdev, struct swiotlb_phys_addr buffer, size_t size, int dir) |
1da177e4 LT |
396 | { |
397 | unsigned long flags; | |
398 | char *dma_addr; | |
399 | unsigned int nslots, stride, index, wrap; | |
400 | int i; | |
681cc5cd FT |
401 | unsigned long start_dma_addr; |
402 | unsigned long mask; | |
403 | unsigned long offset_slots; | |
404 | unsigned long max_slots; | |
ef9b1893 | 405 | struct swiotlb_phys_addr slot_buf; |
681cc5cd FT |
406 | |
407 | mask = dma_get_seg_boundary(hwdev); | |
e08e1f7a | 408 | start_dma_addr = swiotlb_virt_to_bus(io_tlb_start) & mask; |
681cc5cd FT |
409 | |
410 | offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; | |
a5ddde4a IC |
411 | |
412 | /* | |
413 | * Carefully handle integer overflow which can occur when mask == ~0UL. | |
414 | */ | |
b15a3891 JB |
415 | max_slots = mask + 1 |
416 | ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT | |
417 | : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT); | |
1da177e4 LT |
418 | |
419 | /* | |
420 | * For mappings greater than a page, we limit the stride (and | |
421 | * hence alignment) to a page size. | |
422 | */ | |
423 | nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; | |
424 | if (size > PAGE_SIZE) | |
425 | stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT)); | |
426 | else | |
427 | stride = 1; | |
428 | ||
34814545 | 429 | BUG_ON(!nslots); |
1da177e4 LT |
430 | |
431 | /* | |
432 | * Find suitable number of IO TLB entries size that will fit this | |
433 | * request and allocate a buffer from that IO TLB pool. | |
434 | */ | |
435 | spin_lock_irqsave(&io_tlb_lock, flags); | |
a7133a15 AM |
436 | index = ALIGN(io_tlb_index, stride); |
437 | if (index >= io_tlb_nslabs) | |
438 | index = 0; | |
439 | wrap = index; | |
440 | ||
441 | do { | |
a8522509 FT |
442 | while (iommu_is_span_boundary(index, nslots, offset_slots, |
443 | max_slots)) { | |
b15a3891 JB |
444 | index += stride; |
445 | if (index >= io_tlb_nslabs) | |
446 | index = 0; | |
a7133a15 AM |
447 | if (index == wrap) |
448 | goto not_found; | |
449 | } | |
450 | ||
451 | /* | |
452 | * If we find a slot that indicates we have 'nslots' number of | |
453 | * contiguous buffers, we allocate the buffers from that slot | |
454 | * and mark the entries as '0' indicating unavailable. | |
455 | */ | |
456 | if (io_tlb_list[index] >= nslots) { | |
457 | int count = 0; | |
458 | ||
459 | for (i = index; i < (int) (index + nslots); i++) | |
460 | io_tlb_list[i] = 0; | |
461 | for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--) | |
462 | io_tlb_list[i] = ++count; | |
463 | dma_addr = io_tlb_start + (index << IO_TLB_SHIFT); | |
1da177e4 | 464 | |
a7133a15 AM |
465 | /* |
466 | * Update the indices to avoid searching in the next | |
467 | * round. | |
468 | */ | |
469 | io_tlb_index = ((index + nslots) < io_tlb_nslabs | |
470 | ? (index + nslots) : 0); | |
471 | ||
472 | goto found; | |
473 | } | |
474 | index += stride; | |
475 | if (index >= io_tlb_nslabs) | |
476 | index = 0; | |
477 | } while (index != wrap); | |
478 | ||
479 | not_found: | |
480 | spin_unlock_irqrestore(&io_tlb_lock, flags); | |
481 | return NULL; | |
482 | found: | |
1da177e4 LT |
483 | spin_unlock_irqrestore(&io_tlb_lock, flags); |
484 | ||
485 | /* | |
486 | * Save away the mapping from the original address to the DMA address. | |
487 | * This is needed when we sync the memory. Then we sync the buffer if | |
488 | * needed. | |
489 | */ | |
ef9b1893 JF |
490 | slot_buf = buffer; |
491 | for (i = 0; i < nslots; i++) { | |
492 | slot_buf.page += slot_buf.offset >> PAGE_SHIFT; | |
493 | slot_buf.offset &= PAGE_SIZE - 1; | |
494 | io_tlb_orig_addr[index+i] = slot_buf; | |
495 | slot_buf.offset += 1 << IO_TLB_SHIFT; | |
496 | } | |
1da177e4 | 497 | if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) |
1b548f66 | 498 | __sync_single(buffer, dma_addr, size, DMA_TO_DEVICE); |
1da177e4 LT |
499 | |
500 | return dma_addr; | |
501 | } | |
502 | ||
503 | /* | |
504 | * dma_addr is the kernel virtual address of the bounce buffer to unmap. | |
505 | */ | |
506 | static void | |
507 | unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir) | |
508 | { | |
509 | unsigned long flags; | |
510 | int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; | |
511 | int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT; | |
ef9b1893 | 512 | struct swiotlb_phys_addr buffer = swiotlb_bus_to_phys_addr(dma_addr); |
1da177e4 LT |
513 | |
514 | /* | |
515 | * First, sync the memory before unmapping the entry | |
516 | */ | |
ef9b1893 | 517 | if ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)) |
1da177e4 LT |
518 | /* |
519 | * bounce... copy the data back into the original buffer * and | |
520 | * delete the bounce buffer. | |
521 | */ | |
1b548f66 | 522 | __sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE); |
1da177e4 LT |
523 | |
524 | /* | |
525 | * Return the buffer to the free list by setting the corresponding | |
526 | * entries to indicate the number of contigous entries available. | |
527 | * While returning the entries to the free list, we merge the entries | |
528 | * with slots below and above the pool being returned. | |
529 | */ | |
530 | spin_lock_irqsave(&io_tlb_lock, flags); | |
531 | { | |
532 | count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ? | |
533 | io_tlb_list[index + nslots] : 0); | |
534 | /* | |
535 | * Step 1: return the slots to the free list, merging the | |
536 | * slots with superceeding slots | |
537 | */ | |
538 | for (i = index + nslots - 1; i >= index; i--) | |
539 | io_tlb_list[i] = ++count; | |
540 | /* | |
541 | * Step 2: merge the returned slots with the preceding slots, | |
542 | * if available (non zero) | |
543 | */ | |
544 | for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--) | |
545 | io_tlb_list[i] = ++count; | |
546 | } | |
547 | spin_unlock_irqrestore(&io_tlb_lock, flags); | |
548 | } | |
549 | ||
550 | static void | |
de69e0f0 JL |
551 | sync_single(struct device *hwdev, char *dma_addr, size_t size, |
552 | int dir, int target) | |
1da177e4 | 553 | { |
ef9b1893 | 554 | struct swiotlb_phys_addr buffer = swiotlb_bus_to_phys_addr(dma_addr); |
df336d1c | 555 | |
de69e0f0 JL |
556 | switch (target) { |
557 | case SYNC_FOR_CPU: | |
558 | if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)) | |
1b548f66 | 559 | __sync_single(buffer, dma_addr, size, DMA_FROM_DEVICE); |
34814545 ES |
560 | else |
561 | BUG_ON(dir != DMA_TO_DEVICE); | |
de69e0f0 JL |
562 | break; |
563 | case SYNC_FOR_DEVICE: | |
564 | if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)) | |
1b548f66 | 565 | __sync_single(buffer, dma_addr, size, DMA_TO_DEVICE); |
34814545 ES |
566 | else |
567 | BUG_ON(dir != DMA_FROM_DEVICE); | |
de69e0f0 JL |
568 | break; |
569 | default: | |
1da177e4 | 570 | BUG(); |
de69e0f0 | 571 | } |
1da177e4 LT |
572 | } |
573 | ||
574 | void * | |
575 | swiotlb_alloc_coherent(struct device *hwdev, size_t size, | |
06a54497 | 576 | dma_addr_t *dma_handle, gfp_t flags) |
1da177e4 | 577 | { |
563aaf06 | 578 | dma_addr_t dev_addr; |
1da177e4 LT |
579 | void *ret; |
580 | int order = get_order(size); | |
1e74f300 FT |
581 | u64 dma_mask = DMA_32BIT_MASK; |
582 | ||
583 | if (hwdev && hwdev->coherent_dma_mask) | |
584 | dma_mask = hwdev->coherent_dma_mask; | |
1da177e4 | 585 | |
25667d67 | 586 | ret = (void *)__get_free_pages(flags, order); |
e08e1f7a | 587 | if (ret && !is_buffer_dma_capable(dma_mask, swiotlb_virt_to_bus(ret), size)) { |
1da177e4 LT |
588 | /* |
589 | * The allocated memory isn't reachable by the device. | |
590 | * Fall back on swiotlb_map_single(). | |
591 | */ | |
592 | free_pages((unsigned long) ret, order); | |
593 | ret = NULL; | |
594 | } | |
595 | if (!ret) { | |
596 | /* | |
597 | * We are either out of memory or the device can't DMA | |
598 | * to GFP_DMA memory; fall back on | |
599 | * swiotlb_map_single(), which will grab memory from | |
600 | * the lowest available address range. | |
601 | */ | |
ef9b1893 JF |
602 | struct swiotlb_phys_addr buffer; |
603 | buffer.page = virt_to_page(NULL); | |
604 | buffer.offset = 0; | |
605 | ret = map_single(hwdev, buffer, size, DMA_FROM_DEVICE); | |
9dfda12b | 606 | if (!ret) |
1da177e4 | 607 | return NULL; |
1da177e4 LT |
608 | } |
609 | ||
610 | memset(ret, 0, size); | |
e08e1f7a | 611 | dev_addr = swiotlb_virt_to_bus(ret); |
1da177e4 LT |
612 | |
613 | /* Confirm address can be DMA'd by device */ | |
1e74f300 | 614 | if (!is_buffer_dma_capable(dma_mask, dev_addr, size)) { |
563aaf06 | 615 | printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", |
1e74f300 | 616 | (unsigned long long)dma_mask, |
563aaf06 | 617 | (unsigned long long)dev_addr); |
a2b89b59 FT |
618 | |
619 | /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ | |
620 | unmap_single(hwdev, ret, size, DMA_TO_DEVICE); | |
621 | return NULL; | |
1da177e4 LT |
622 | } |
623 | *dma_handle = dev_addr; | |
624 | return ret; | |
625 | } | |
626 | ||
627 | void | |
628 | swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, | |
629 | dma_addr_t dma_handle) | |
630 | { | |
aa24886e | 631 | WARN_ON(irqs_disabled()); |
640aebfe | 632 | if (!is_swiotlb_buffer(vaddr)) |
1da177e4 LT |
633 | free_pages((unsigned long) vaddr, get_order(size)); |
634 | else | |
635 | /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ | |
21f6c4de | 636 | unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE); |
1da177e4 LT |
637 | } |
638 | ||
639 | static void | |
640 | swiotlb_full(struct device *dev, size_t size, int dir, int do_panic) | |
641 | { | |
642 | /* | |
643 | * Ran out of IOMMU space for this operation. This is very bad. | |
644 | * Unfortunately the drivers cannot handle this operation properly. | |
17e5ad6c | 645 | * unless they check for dma_mapping_error (most don't) |
1da177e4 LT |
646 | * When the mapping is small enough return a static buffer to limit |
647 | * the damage, or panic when the transfer is too big. | |
648 | */ | |
563aaf06 | 649 | printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at " |
1da177e4 LT |
650 | "device %s\n", size, dev ? dev->bus_id : "?"); |
651 | ||
652 | if (size > io_tlb_overflow && do_panic) { | |
17e5ad6c TL |
653 | if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL) |
654 | panic("DMA: Memory would be corrupted\n"); | |
655 | if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL) | |
656 | panic("DMA: Random memory would be DMAed\n"); | |
1da177e4 LT |
657 | } |
658 | } | |
659 | ||
660 | /* | |
661 | * Map a single buffer of the indicated size for DMA in streaming mode. The | |
17e5ad6c | 662 | * physical address to use is returned. |
1da177e4 LT |
663 | * |
664 | * Once the device is given the dma address, the device owns this memory until | |
665 | * either swiotlb_unmap_single or swiotlb_dma_sync_single is performed. | |
666 | */ | |
667 | dma_addr_t | |
309df0c5 AK |
668 | swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size, |
669 | int dir, struct dma_attrs *attrs) | |
1da177e4 | 670 | { |
e08e1f7a | 671 | dma_addr_t dev_addr = swiotlb_virt_to_bus(ptr); |
1da177e4 | 672 | void *map; |
ef9b1893 | 673 | struct swiotlb_phys_addr buffer; |
1da177e4 | 674 | |
34814545 | 675 | BUG_ON(dir == DMA_NONE); |
1da177e4 LT |
676 | /* |
677 | * If the pointer passed in happens to be in the device's DMA window, | |
678 | * we can safely return the device addr and not worry about bounce | |
679 | * buffering it. | |
680 | */ | |
b81ea27b IC |
681 | if (!address_needs_mapping(hwdev, dev_addr, size) && |
682 | !range_needs_mapping(ptr, size)) | |
1da177e4 LT |
683 | return dev_addr; |
684 | ||
685 | /* | |
686 | * Oh well, have to allocate and map a bounce buffer. | |
687 | */ | |
ef9b1893 JF |
688 | buffer.page = virt_to_page(ptr); |
689 | buffer.offset = (unsigned long)ptr & ~PAGE_MASK; | |
690 | map = map_single(hwdev, buffer, size, dir); | |
1da177e4 LT |
691 | if (!map) { |
692 | swiotlb_full(hwdev, size, dir, 1); | |
693 | map = io_tlb_overflow_buffer; | |
694 | } | |
695 | ||
e08e1f7a | 696 | dev_addr = swiotlb_virt_to_bus(map); |
1da177e4 LT |
697 | |
698 | /* | |
699 | * Ensure that the address returned is DMA'ble | |
700 | */ | |
2797982e | 701 | if (address_needs_mapping(hwdev, dev_addr, size)) |
1da177e4 LT |
702 | panic("map_single: bounce buffer is not DMA'ble"); |
703 | ||
704 | return dev_addr; | |
705 | } | |
309df0c5 AK |
706 | EXPORT_SYMBOL(swiotlb_map_single_attrs); |
707 | ||
708 | dma_addr_t | |
709 | swiotlb_map_single(struct device *hwdev, void *ptr, size_t size, int dir) | |
710 | { | |
711 | return swiotlb_map_single_attrs(hwdev, ptr, size, dir, NULL); | |
712 | } | |
1da177e4 | 713 | |
1da177e4 LT |
714 | /* |
715 | * Unmap a single streaming mode DMA translation. The dma_addr and size must | |
716 | * match what was provided for in a previous swiotlb_map_single call. All | |
717 | * other usages are undefined. | |
718 | * | |
719 | * After this call, reads by the cpu to the buffer are guaranteed to see | |
720 | * whatever the device wrote there. | |
721 | */ | |
722 | void | |
309df0c5 AK |
723 | swiotlb_unmap_single_attrs(struct device *hwdev, dma_addr_t dev_addr, |
724 | size_t size, int dir, struct dma_attrs *attrs) | |
1da177e4 | 725 | { |
e08e1f7a | 726 | char *dma_addr = swiotlb_bus_to_virt(dev_addr); |
1da177e4 | 727 | |
34814545 | 728 | BUG_ON(dir == DMA_NONE); |
640aebfe | 729 | if (is_swiotlb_buffer(dma_addr)) |
1da177e4 LT |
730 | unmap_single(hwdev, dma_addr, size, dir); |
731 | else if (dir == DMA_FROM_DEVICE) | |
cde14bbf | 732 | dma_mark_clean(dma_addr, size); |
1da177e4 | 733 | } |
309df0c5 | 734 | EXPORT_SYMBOL(swiotlb_unmap_single_attrs); |
1da177e4 | 735 | |
309df0c5 AK |
736 | void |
737 | swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size, | |
738 | int dir) | |
739 | { | |
740 | return swiotlb_unmap_single_attrs(hwdev, dev_addr, size, dir, NULL); | |
741 | } | |
1da177e4 LT |
742 | /* |
743 | * Make physical memory consistent for a single streaming mode DMA translation | |
744 | * after a transfer. | |
745 | * | |
746 | * If you perform a swiotlb_map_single() but wish to interrogate the buffer | |
17e5ad6c TL |
747 | * using the cpu, yet do not wish to teardown the dma mapping, you must |
748 | * call this function before doing so. At the next point you give the dma | |
1da177e4 LT |
749 | * address back to the card, you must first perform a |
750 | * swiotlb_dma_sync_for_device, and then the device again owns the buffer | |
751 | */ | |
be6b0267 | 752 | static void |
8270f3f1 | 753 | swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr, |
de69e0f0 | 754 | size_t size, int dir, int target) |
1da177e4 | 755 | { |
e08e1f7a | 756 | char *dma_addr = swiotlb_bus_to_virt(dev_addr); |
1da177e4 | 757 | |
34814545 | 758 | BUG_ON(dir == DMA_NONE); |
640aebfe | 759 | if (is_swiotlb_buffer(dma_addr)) |
de69e0f0 | 760 | sync_single(hwdev, dma_addr, size, dir, target); |
1da177e4 | 761 | else if (dir == DMA_FROM_DEVICE) |
cde14bbf | 762 | dma_mark_clean(dma_addr, size); |
1da177e4 LT |
763 | } |
764 | ||
8270f3f1 JL |
765 | void |
766 | swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr, | |
767 | size_t size, int dir) | |
768 | { | |
de69e0f0 | 769 | swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU); |
8270f3f1 JL |
770 | } |
771 | ||
1da177e4 LT |
772 | void |
773 | swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr, | |
774 | size_t size, int dir) | |
775 | { | |
de69e0f0 | 776 | swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE); |
1da177e4 LT |
777 | } |
778 | ||
878a97cf JL |
779 | /* |
780 | * Same as above, but for a sub-range of the mapping. | |
781 | */ | |
be6b0267 | 782 | static void |
878a97cf | 783 | swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr, |
de69e0f0 JL |
784 | unsigned long offset, size_t size, |
785 | int dir, int target) | |
878a97cf | 786 | { |
e08e1f7a | 787 | char *dma_addr = swiotlb_bus_to_virt(dev_addr) + offset; |
878a97cf | 788 | |
34814545 | 789 | BUG_ON(dir == DMA_NONE); |
640aebfe | 790 | if (is_swiotlb_buffer(dma_addr)) |
de69e0f0 | 791 | sync_single(hwdev, dma_addr, size, dir, target); |
878a97cf | 792 | else if (dir == DMA_FROM_DEVICE) |
cde14bbf | 793 | dma_mark_clean(dma_addr, size); |
878a97cf JL |
794 | } |
795 | ||
796 | void | |
797 | swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr, | |
798 | unsigned long offset, size_t size, int dir) | |
799 | { | |
de69e0f0 JL |
800 | swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir, |
801 | SYNC_FOR_CPU); | |
878a97cf JL |
802 | } |
803 | ||
804 | void | |
805 | swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr, | |
806 | unsigned long offset, size_t size, int dir) | |
807 | { | |
de69e0f0 JL |
808 | swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir, |
809 | SYNC_FOR_DEVICE); | |
878a97cf JL |
810 | } |
811 | ||
309df0c5 AK |
812 | void swiotlb_unmap_sg_attrs(struct device *, struct scatterlist *, int, int, |
813 | struct dma_attrs *); | |
1da177e4 LT |
814 | /* |
815 | * Map a set of buffers described by scatterlist in streaming mode for DMA. | |
816 | * This is the scatter-gather version of the above swiotlb_map_single | |
817 | * interface. Here the scatter gather list elements are each tagged with the | |
818 | * appropriate dma address and length. They are obtained via | |
819 | * sg_dma_{address,length}(SG). | |
820 | * | |
821 | * NOTE: An implementation may be able to use a smaller number of | |
822 | * DMA address/length pairs than there are SG table elements. | |
823 | * (for example via virtual mapping capabilities) | |
824 | * The routine returns the number of addr/length pairs actually | |
825 | * used, at most nents. | |
826 | * | |
827 | * Device ownership issues as mentioned above for swiotlb_map_single are the | |
828 | * same here. | |
829 | */ | |
830 | int | |
309df0c5 AK |
831 | swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems, |
832 | int dir, struct dma_attrs *attrs) | |
1da177e4 | 833 | { |
dbfd49fe | 834 | struct scatterlist *sg; |
ef9b1893 | 835 | struct swiotlb_phys_addr buffer; |
563aaf06 | 836 | dma_addr_t dev_addr; |
1da177e4 LT |
837 | int i; |
838 | ||
34814545 | 839 | BUG_ON(dir == DMA_NONE); |
1da177e4 | 840 | |
dbfd49fe | 841 | for_each_sg(sgl, sg, nelems, i) { |
ef9b1893 | 842 | dev_addr = swiotlb_sg_to_bus(sg); |
b81ea27b | 843 | if (range_needs_mapping(sg_virt(sg), sg->length) || |
2797982e | 844 | address_needs_mapping(hwdev, dev_addr, sg->length)) { |
ef9b1893 JF |
845 | void *map; |
846 | buffer.page = sg_page(sg); | |
847 | buffer.offset = sg->offset; | |
848 | map = map_single(hwdev, buffer, sg->length, dir); | |
7e870233 | 849 | if (!map) { |
1da177e4 LT |
850 | /* Don't panic here, we expect map_sg users |
851 | to do proper error handling. */ | |
852 | swiotlb_full(hwdev, sg->length, dir, 0); | |
309df0c5 AK |
853 | swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir, |
854 | attrs); | |
dbfd49fe | 855 | sgl[0].dma_length = 0; |
1da177e4 LT |
856 | return 0; |
857 | } | |
e08e1f7a | 858 | sg->dma_address = swiotlb_virt_to_bus(map); |
1da177e4 LT |
859 | } else |
860 | sg->dma_address = dev_addr; | |
861 | sg->dma_length = sg->length; | |
862 | } | |
863 | return nelems; | |
864 | } | |
309df0c5 AK |
865 | EXPORT_SYMBOL(swiotlb_map_sg_attrs); |
866 | ||
867 | int | |
868 | swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems, | |
869 | int dir) | |
870 | { | |
871 | return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL); | |
872 | } | |
1da177e4 LT |
873 | |
874 | /* | |
875 | * Unmap a set of streaming mode DMA translations. Again, cpu read rules | |
876 | * concerning calls here are the same as for swiotlb_unmap_single() above. | |
877 | */ | |
878 | void | |
309df0c5 AK |
879 | swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl, |
880 | int nelems, int dir, struct dma_attrs *attrs) | |
1da177e4 | 881 | { |
dbfd49fe | 882 | struct scatterlist *sg; |
1da177e4 LT |
883 | int i; |
884 | ||
34814545 | 885 | BUG_ON(dir == DMA_NONE); |
1da177e4 | 886 | |
dbfd49fe | 887 | for_each_sg(sgl, sg, nelems, i) { |
ef9b1893 | 888 | if (sg->dma_address != swiotlb_sg_to_bus(sg)) |
e08e1f7a | 889 | unmap_single(hwdev, swiotlb_bus_to_virt(sg->dma_address), |
93fbff63 | 890 | sg->dma_length, dir); |
1da177e4 | 891 | else if (dir == DMA_FROM_DEVICE) |
ef9b1893 | 892 | dma_mark_clean(swiotlb_bus_to_virt(sg->dma_address), sg->dma_length); |
dbfd49fe | 893 | } |
1da177e4 | 894 | } |
309df0c5 AK |
895 | EXPORT_SYMBOL(swiotlb_unmap_sg_attrs); |
896 | ||
897 | void | |
898 | swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems, | |
899 | int dir) | |
900 | { | |
901 | return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL); | |
902 | } | |
1da177e4 LT |
903 | |
904 | /* | |
905 | * Make physical memory consistent for a set of streaming mode DMA translations | |
906 | * after a transfer. | |
907 | * | |
908 | * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules | |
909 | * and usage. | |
910 | */ | |
be6b0267 | 911 | static void |
dbfd49fe | 912 | swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl, |
de69e0f0 | 913 | int nelems, int dir, int target) |
1da177e4 | 914 | { |
dbfd49fe | 915 | struct scatterlist *sg; |
1da177e4 LT |
916 | int i; |
917 | ||
34814545 | 918 | BUG_ON(dir == DMA_NONE); |
1da177e4 | 919 | |
dbfd49fe | 920 | for_each_sg(sgl, sg, nelems, i) { |
ef9b1893 | 921 | if (sg->dma_address != swiotlb_sg_to_bus(sg)) |
e08e1f7a | 922 | sync_single(hwdev, swiotlb_bus_to_virt(sg->dma_address), |
de69e0f0 | 923 | sg->dma_length, dir, target); |
cde14bbf | 924 | else if (dir == DMA_FROM_DEVICE) |
ef9b1893 | 925 | dma_mark_clean(swiotlb_bus_to_virt(sg->dma_address), sg->dma_length); |
dbfd49fe | 926 | } |
1da177e4 LT |
927 | } |
928 | ||
8270f3f1 JL |
929 | void |
930 | swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg, | |
931 | int nelems, int dir) | |
932 | { | |
de69e0f0 | 933 | swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU); |
8270f3f1 JL |
934 | } |
935 | ||
1da177e4 LT |
936 | void |
937 | swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg, | |
938 | int nelems, int dir) | |
939 | { | |
de69e0f0 | 940 | swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE); |
1da177e4 LT |
941 | } |
942 | ||
943 | int | |
8d8bb39b | 944 | swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr) |
1da177e4 | 945 | { |
e08e1f7a | 946 | return (dma_addr == swiotlb_virt_to_bus(io_tlb_overflow_buffer)); |
1da177e4 LT |
947 | } |
948 | ||
949 | /* | |
17e5ad6c | 950 | * Return whether the given device DMA address mask can be supported |
1da177e4 | 951 | * properly. For example, if your device can only drive the low 24-bits |
17e5ad6c | 952 | * during bus mastering, then you would pass 0x00ffffff as the mask to |
1da177e4 LT |
953 | * this function. |
954 | */ | |
955 | int | |
563aaf06 | 956 | swiotlb_dma_supported(struct device *hwdev, u64 mask) |
1da177e4 | 957 | { |
e08e1f7a | 958 | return swiotlb_virt_to_bus(io_tlb_end - 1) <= mask; |
1da177e4 LT |
959 | } |
960 | ||
1da177e4 LT |
961 | EXPORT_SYMBOL(swiotlb_map_single); |
962 | EXPORT_SYMBOL(swiotlb_unmap_single); | |
963 | EXPORT_SYMBOL(swiotlb_map_sg); | |
964 | EXPORT_SYMBOL(swiotlb_unmap_sg); | |
965 | EXPORT_SYMBOL(swiotlb_sync_single_for_cpu); | |
966 | EXPORT_SYMBOL(swiotlb_sync_single_for_device); | |
878a97cf JL |
967 | EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu); |
968 | EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device); | |
1da177e4 LT |
969 | EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu); |
970 | EXPORT_SYMBOL(swiotlb_sync_sg_for_device); | |
971 | EXPORT_SYMBOL(swiotlb_dma_mapping_error); | |
25667d67 TL |
972 | EXPORT_SYMBOL(swiotlb_alloc_coherent); |
973 | EXPORT_SYMBOL(swiotlb_free_coherent); | |
1da177e4 | 974 | EXPORT_SYMBOL(swiotlb_dma_supported); |