blob: f8eebd489149e5c0cd7177ce98a5246bc25b32f3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Dynamic DMA mapping support.
3 *
Jan Beulich563aaf02007-02-05 18:51:25 -08004 * This implementation is a fallback for platforms that do not support
Linus Torvalds1da177e2005-04-16 15:20:36 -07005 * 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.
John W. Linville569c8bf2005-09-29 14:45:24 -070014 * 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.
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 */
18
19#include <linux/cache.h>
Tony Luck17e5ad62005-09-29 15:52:13 -070020#include <linux/dma-mapping.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021#include <linux/mm.h>
22#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#include <linux/spinlock.h>
24#include <linux/string.h>
25#include <linux/types.h>
26#include <linux/ctype.h>
27
28#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070029#include <asm/dma.h>
Tony Luck17e5ad62005-09-29 15:52:13 -070030#include <asm/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#include <linux/init.h>
33#include <linux/bootmem.h>
FUJITA Tomonoria8522502008-04-29 00:59:36 -070034#include <linux/iommu-helper.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36#define OFFSET(val,align) ((unsigned long) \
37 ( (val) & ( (align) - 1)))
38
Jens Axboef9527f12007-10-22 19:44:53 +020039#define SG_ENT_VIRT_ADDRESS(sg) (sg_virt((sg)))
Jan Beulich93fbff62007-02-05 18:49:45 -080040#define SG_ENT_PHYS_ADDRESS(sg) virt_to_bus(SG_ENT_VIRT_ADDRESS(sg))
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
42/*
43 * Maximum allowable number of contiguous slabs to map,
44 * must be a power of 2. What is the appropriate value ?
45 * The complexity of {map,unmap}_single is linearly dependent on this value.
46 */
47#define IO_TLB_SEGSIZE 128
48
49/*
50 * log of the size of each IO TLB slab. The number of slabs is command line
51 * controllable.
52 */
53#define IO_TLB_SHIFT 11
54
Alex Williamson0b9afed2005-09-06 11:20:49 -060055#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
56
57/*
58 * Minimum IO TLB size to bother booting with. Systems with mainly
59 * 64bit capable cards will only lightly use the swiotlb. If we can't
60 * allocate a contiguous 1MB, we're probably in trouble anyway.
61 */
62#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
63
John W. Linvillede69e0f2005-09-29 14:44:57 -070064/*
65 * Enumeration for sync targets
66 */
67enum dma_sync_target {
68 SYNC_FOR_CPU = 0,
69 SYNC_FOR_DEVICE = 1,
70};
71
Linus Torvalds1da177e2005-04-16 15:20:36 -070072int swiotlb_force;
73
74/*
75 * Used to do a quick range check in swiotlb_unmap_single and
76 * swiotlb_sync_single_*, to see if the memory was in fact allocated by this
77 * API.
78 */
79static char *io_tlb_start, *io_tlb_end;
80
81/*
82 * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
83 * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
84 */
85static unsigned long io_tlb_nslabs;
86
87/*
88 * When the IOMMU overflows we return a fallback buffer. This sets the size.
89 */
90static unsigned long io_tlb_overflow = 32*1024;
91
92void *io_tlb_overflow_buffer;
93
94/*
95 * This is a free list describing the number of free entries available from
96 * each index
97 */
98static unsigned int *io_tlb_list;
99static unsigned int io_tlb_index;
100
101/*
102 * We need to save away the original address corresponding to a mapped entry
103 * for the sync operations.
104 */
Tony Luck25667d62007-03-06 13:31:45 -0800105static unsigned char **io_tlb_orig_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106
107/*
108 * Protect the above data structures in the map and unmap calls
109 */
110static DEFINE_SPINLOCK(io_tlb_lock);
111
112static int __init
113setup_io_tlb_npages(char *str)
114{
115 if (isdigit(*str)) {
Alex Williamsone8579e72005-08-04 13:06:00 -0700116 io_tlb_nslabs = simple_strtoul(str, &str, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 /* avoid tail segment of size < IO_TLB_SEGSIZE */
118 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
119 }
120 if (*str == ',')
121 ++str;
122 if (!strcmp(str, "force"))
123 swiotlb_force = 1;
124 return 1;
125}
126__setup("swiotlb=", setup_io_tlb_npages);
127/* make io_tlb_overflow tunable too? */
128
129/*
130 * Statically reserve bounce buffer space and initialize bounce buffer data
Tony Luck17e5ad62005-09-29 15:52:13 -0700131 * structures for the software IO TLB used to implement the DMA API.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800133void __init
134swiotlb_init_with_default_size(size_t default_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700135{
Jan Beulich563aaf02007-02-05 18:51:25 -0800136 unsigned long i, bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137
138 if (!io_tlb_nslabs) {
Alex Williamsone8579e72005-08-04 13:06:00 -0700139 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700140 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
141 }
142
Jan Beulich563aaf02007-02-05 18:51:25 -0800143 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
144
Linus Torvalds1da177e2005-04-16 15:20:36 -0700145 /*
146 * Get IO TLB memory from the low pages
147 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800148 io_tlb_start = alloc_bootmem_low_pages(bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 if (!io_tlb_start)
150 panic("Cannot allocate SWIOTLB buffer");
Jan Beulich563aaf02007-02-05 18:51:25 -0800151 io_tlb_end = io_tlb_start + bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700152
153 /*
154 * Allocate and initialize the free list array. This array is used
155 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
156 * between io_tlb_start and io_tlb_end.
157 */
158 io_tlb_list = alloc_bootmem(io_tlb_nslabs * sizeof(int));
Tony Luck25667d62007-03-06 13:31:45 -0800159 for (i = 0; i < io_tlb_nslabs; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
161 io_tlb_index = 0;
Tony Luck25667d62007-03-06 13:31:45 -0800162 io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(char *));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163
164 /*
165 * Get the overflow emergency buffer
166 */
167 io_tlb_overflow_buffer = alloc_bootmem_low(io_tlb_overflow);
Jan Beulich563aaf02007-02-05 18:51:25 -0800168 if (!io_tlb_overflow_buffer)
169 panic("Cannot allocate SWIOTLB overflow buffer!\n");
170
Tony Luck25667d62007-03-06 13:31:45 -0800171 printk(KERN_INFO "Placing software IO TLB between 0x%lx - 0x%lx\n",
172 virt_to_bus(io_tlb_start), virt_to_bus(io_tlb_end));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173}
174
Jan Beulich563aaf02007-02-05 18:51:25 -0800175void __init
176swiotlb_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177{
Tony Luck25667d62007-03-06 13:31:45 -0800178 swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179}
180
Alex Williamson0b9afed2005-09-06 11:20:49 -0600181/*
182 * Systems with larger DMA zones (those that don't support ISA) can
183 * initialize the swiotlb later using the slab allocator if needed.
184 * This should be just like above, but with some error catching.
185 */
186int
Jan Beulich563aaf02007-02-05 18:51:25 -0800187swiotlb_late_init_with_default_size(size_t default_size)
Alex Williamson0b9afed2005-09-06 11:20:49 -0600188{
Jan Beulich563aaf02007-02-05 18:51:25 -0800189 unsigned long i, bytes, req_nslabs = io_tlb_nslabs;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600190 unsigned int order;
191
192 if (!io_tlb_nslabs) {
193 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
194 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
195 }
196
197 /*
198 * Get IO TLB memory from the low pages
199 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800200 order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600201 io_tlb_nslabs = SLABS_PER_PAGE << order;
Jan Beulich563aaf02007-02-05 18:51:25 -0800202 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600203
204 while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
205 io_tlb_start = (char *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
206 order);
207 if (io_tlb_start)
208 break;
209 order--;
210 }
211
212 if (!io_tlb_start)
213 goto cleanup1;
214
Jan Beulich563aaf02007-02-05 18:51:25 -0800215 if (order != get_order(bytes)) {
Alex Williamson0b9afed2005-09-06 11:20:49 -0600216 printk(KERN_WARNING "Warning: only able to allocate %ld MB "
217 "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
218 io_tlb_nslabs = SLABS_PER_PAGE << order;
Jan Beulich563aaf02007-02-05 18:51:25 -0800219 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600220 }
Jan Beulich563aaf02007-02-05 18:51:25 -0800221 io_tlb_end = io_tlb_start + bytes;
222 memset(io_tlb_start, 0, bytes);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600223
224 /*
225 * Allocate and initialize the free list array. This array is used
226 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
227 * between io_tlb_start and io_tlb_end.
228 */
229 io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
230 get_order(io_tlb_nslabs * sizeof(int)));
231 if (!io_tlb_list)
232 goto cleanup2;
233
234 for (i = 0; i < io_tlb_nslabs; i++)
235 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
236 io_tlb_index = 0;
237
Tony Luck25667d62007-03-06 13:31:45 -0800238 io_tlb_orig_addr = (unsigned char **)__get_free_pages(GFP_KERNEL,
239 get_order(io_tlb_nslabs * sizeof(char *)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600240 if (!io_tlb_orig_addr)
241 goto cleanup3;
242
Tony Luck25667d62007-03-06 13:31:45 -0800243 memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(char *));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600244
245 /*
246 * Get the overflow emergency buffer
247 */
248 io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
249 get_order(io_tlb_overflow));
250 if (!io_tlb_overflow_buffer)
251 goto cleanup4;
252
Tony Luck25667d62007-03-06 13:31:45 -0800253 printk(KERN_INFO "Placing %luMB software IO TLB between 0x%lx - "
254 "0x%lx\n", bytes >> 20,
255 virt_to_bus(io_tlb_start), virt_to_bus(io_tlb_end));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600256
257 return 0;
258
259cleanup4:
Tony Luck25667d62007-03-06 13:31:45 -0800260 free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs *
261 sizeof(char *)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600262 io_tlb_orig_addr = NULL;
263cleanup3:
Tony Luck25667d62007-03-06 13:31:45 -0800264 free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
265 sizeof(int)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600266 io_tlb_list = NULL;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600267cleanup2:
Jan Beulich563aaf02007-02-05 18:51:25 -0800268 io_tlb_end = NULL;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600269 free_pages((unsigned long)io_tlb_start, order);
270 io_tlb_start = NULL;
271cleanup1:
272 io_tlb_nslabs = req_nslabs;
273 return -ENOMEM;
274}
275
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800276static int
FUJITA Tomonori27979822008-09-10 01:06:49 +0900277address_needs_mapping(struct device *hwdev, dma_addr_t addr, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278{
FUJITA Tomonori07a2c012008-09-19 02:02:05 +0900279 return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700280}
281
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900282static int is_swiotlb_buffer(char *addr)
283{
284 return addr >= io_tlb_start && addr < io_tlb_end;
285}
286
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287/*
288 * Allocates bounce buffer and returns its kernel virtual address.
289 */
290static void *
Tony Luck25667d62007-03-06 13:31:45 -0800291map_single(struct device *hwdev, char *buffer, size_t size, int dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700292{
293 unsigned long flags;
294 char *dma_addr;
295 unsigned int nslots, stride, index, wrap;
296 int i;
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800297 unsigned long start_dma_addr;
298 unsigned long mask;
299 unsigned long offset_slots;
300 unsigned long max_slots;
301
302 mask = dma_get_seg_boundary(hwdev);
303 start_dma_addr = virt_to_bus(io_tlb_start) & mask;
304
305 offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
Jan Beulichb15a38912008-03-13 09:13:30 +0000306 max_slots = mask + 1
307 ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
308 : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309
310 /*
311 * For mappings greater than a page, we limit the stride (and
312 * hence alignment) to a page size.
313 */
314 nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
315 if (size > PAGE_SIZE)
316 stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
317 else
318 stride = 1;
319
Eric Sesterhenn34814542006-03-24 18:47:11 +0100320 BUG_ON(!nslots);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321
322 /*
323 * Find suitable number of IO TLB entries size that will fit this
324 * request and allocate a buffer from that IO TLB pool.
325 */
326 spin_lock_irqsave(&io_tlb_lock, flags);
Andrew Mortona7133a12008-04-29 00:59:36 -0700327 index = ALIGN(io_tlb_index, stride);
328 if (index >= io_tlb_nslabs)
329 index = 0;
330 wrap = index;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Andrew Mortona7133a12008-04-29 00:59:36 -0700332 do {
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700333 while (iommu_is_span_boundary(index, nslots, offset_slots,
334 max_slots)) {
Jan Beulichb15a38912008-03-13 09:13:30 +0000335 index += stride;
336 if (index >= io_tlb_nslabs)
337 index = 0;
Andrew Mortona7133a12008-04-29 00:59:36 -0700338 if (index == wrap)
339 goto not_found;
340 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700341
Andrew Mortona7133a12008-04-29 00:59:36 -0700342 /*
343 * If we find a slot that indicates we have 'nslots' number of
344 * contiguous buffers, we allocate the buffers from that slot
345 * and mark the entries as '0' indicating unavailable.
346 */
347 if (io_tlb_list[index] >= nslots) {
348 int count = 0;
349
350 for (i = index; i < (int) (index + nslots); i++)
351 io_tlb_list[i] = 0;
352 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
353 io_tlb_list[i] = ++count;
354 dma_addr = io_tlb_start + (index << IO_TLB_SHIFT);
355
356 /*
357 * Update the indices to avoid searching in the next
358 * round.
359 */
360 io_tlb_index = ((index + nslots) < io_tlb_nslabs
361 ? (index + nslots) : 0);
362
363 goto found;
364 }
365 index += stride;
366 if (index >= io_tlb_nslabs)
367 index = 0;
368 } while (index != wrap);
369
370not_found:
371 spin_unlock_irqrestore(&io_tlb_lock, flags);
372 return NULL;
373found:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 spin_unlock_irqrestore(&io_tlb_lock, flags);
375
376 /*
377 * Save away the mapping from the original address to the DMA address.
378 * This is needed when we sync the memory. Then we sync the buffer if
379 * needed.
380 */
Keir Fraserdf336d12007-07-21 04:37:24 -0700381 for (i = 0; i < nslots; i++)
382 io_tlb_orig_addr[index+i] = buffer + (i << IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700383 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
Tony Luck25667d62007-03-06 13:31:45 -0800384 memcpy(dma_addr, buffer, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385
386 return dma_addr;
387}
388
389/*
390 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
391 */
392static void
393unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
394{
395 unsigned long flags;
396 int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
397 int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
Tony Luck25667d62007-03-06 13:31:45 -0800398 char *buffer = io_tlb_orig_addr[index];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700399
400 /*
401 * First, sync the memory before unmapping the entry
402 */
Tony Luck25667d62007-03-06 13:31:45 -0800403 if (buffer && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404 /*
405 * bounce... copy the data back into the original buffer * and
406 * delete the bounce buffer.
407 */
Tony Luck25667d62007-03-06 13:31:45 -0800408 memcpy(buffer, dma_addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700409
410 /*
411 * Return the buffer to the free list by setting the corresponding
412 * entries to indicate the number of contigous entries available.
413 * While returning the entries to the free list, we merge the entries
414 * with slots below and above the pool being returned.
415 */
416 spin_lock_irqsave(&io_tlb_lock, flags);
417 {
418 count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
419 io_tlb_list[index + nslots] : 0);
420 /*
421 * Step 1: return the slots to the free list, merging the
422 * slots with superceeding slots
423 */
424 for (i = index + nslots - 1; i >= index; i--)
425 io_tlb_list[i] = ++count;
426 /*
427 * Step 2: merge the returned slots with the preceding slots,
428 * if available (non zero)
429 */
430 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
431 io_tlb_list[i] = ++count;
432 }
433 spin_unlock_irqrestore(&io_tlb_lock, flags);
434}
435
436static void
John W. Linvillede69e0f2005-09-29 14:44:57 -0700437sync_single(struct device *hwdev, char *dma_addr, size_t size,
438 int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700439{
440 int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
Tony Luck25667d62007-03-06 13:31:45 -0800441 char *buffer = io_tlb_orig_addr[index];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442
Keir Fraserdf336d12007-07-21 04:37:24 -0700443 buffer += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
444
John W. Linvillede69e0f2005-09-29 14:44:57 -0700445 switch (target) {
446 case SYNC_FOR_CPU:
447 if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
Tony Luck25667d62007-03-06 13:31:45 -0800448 memcpy(buffer, dma_addr, size);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100449 else
450 BUG_ON(dir != DMA_TO_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700451 break;
452 case SYNC_FOR_DEVICE:
453 if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
Tony Luck25667d62007-03-06 13:31:45 -0800454 memcpy(dma_addr, buffer, size);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100455 else
456 BUG_ON(dir != DMA_FROM_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700457 break;
458 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700459 BUG();
John W. Linvillede69e0f2005-09-29 14:44:57 -0700460 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700461}
462
463void *
464swiotlb_alloc_coherent(struct device *hwdev, size_t size,
Al Viro06a54492005-10-21 03:21:03 -0400465 dma_addr_t *dma_handle, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700466{
Jan Beulich563aaf02007-02-05 18:51:25 -0800467 dma_addr_t dev_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 void *ret;
469 int order = get_order(size);
470
Tony Luck25667d62007-03-06 13:31:45 -0800471 ret = (void *)__get_free_pages(flags, order);
FUJITA Tomonori27979822008-09-10 01:06:49 +0900472 if (ret && address_needs_mapping(hwdev, virt_to_bus(ret), size)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700473 /*
474 * The allocated memory isn't reachable by the device.
475 * Fall back on swiotlb_map_single().
476 */
477 free_pages((unsigned long) ret, order);
478 ret = NULL;
479 }
480 if (!ret) {
481 /*
482 * We are either out of memory or the device can't DMA
483 * to GFP_DMA memory; fall back on
484 * swiotlb_map_single(), which will grab memory from
485 * the lowest available address range.
486 */
FUJITA Tomonori9dfda122008-09-08 18:53:48 +0900487 ret = map_single(hwdev, NULL, size, DMA_FROM_DEVICE);
488 if (!ret)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490 }
491
492 memset(ret, 0, size);
Jan Beulich93fbff62007-02-05 18:49:45 -0800493 dev_addr = virt_to_bus(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494
495 /* Confirm address can be DMA'd by device */
FUJITA Tomonori27979822008-09-10 01:06:49 +0900496 if (address_needs_mapping(hwdev, dev_addr, size)) {
Jan Beulich563aaf02007-02-05 18:51:25 -0800497 printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
498 (unsigned long long)*hwdev->dma_mask,
499 (unsigned long long)dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 panic("swiotlb_alloc_coherent: allocated memory is out of "
501 "range for device");
502 }
503 *dma_handle = dev_addr;
504 return ret;
505}
506
507void
508swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
509 dma_addr_t dma_handle)
510{
David Brownellaa248862007-08-10 13:10:27 -0700511 WARN_ON(irqs_disabled());
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900512 if (!is_swiotlb_buffer(vaddr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700513 free_pages((unsigned long) vaddr, get_order(size));
514 else
515 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
FUJITA Tomonori21f6c4d2008-09-08 18:53:49 +0900516 unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700517}
518
519static void
520swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
521{
522 /*
523 * Ran out of IOMMU space for this operation. This is very bad.
524 * Unfortunately the drivers cannot handle this operation properly.
Tony Luck17e5ad62005-09-29 15:52:13 -0700525 * unless they check for dma_mapping_error (most don't)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 * When the mapping is small enough return a static buffer to limit
527 * the damage, or panic when the transfer is too big.
528 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800529 printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
Linus Torvalds1da177e2005-04-16 15:20:36 -0700530 "device %s\n", size, dev ? dev->bus_id : "?");
531
532 if (size > io_tlb_overflow && do_panic) {
Tony Luck17e5ad62005-09-29 15:52:13 -0700533 if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
534 panic("DMA: Memory would be corrupted\n");
535 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
536 panic("DMA: Random memory would be DMAed\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537 }
538}
539
540/*
541 * Map a single buffer of the indicated size for DMA in streaming mode. The
Tony Luck17e5ad62005-09-29 15:52:13 -0700542 * physical address to use is returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700543 *
544 * Once the device is given the dma address, the device owns this memory until
545 * either swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
546 */
547dma_addr_t
Arthur Kepner309df0c2008-04-29 01:00:32 -0700548swiotlb_map_single_attrs(struct device *hwdev, void *ptr, size_t size,
549 int dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700550{
Jan Beulich563aaf02007-02-05 18:51:25 -0800551 dma_addr_t dev_addr = virt_to_bus(ptr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 void *map;
553
Eric Sesterhenn34814542006-03-24 18:47:11 +0100554 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 /*
556 * If the pointer passed in happens to be in the device's DMA window,
557 * we can safely return the device addr and not worry about bounce
558 * buffering it.
559 */
FUJITA Tomonori27979822008-09-10 01:06:49 +0900560 if (!address_needs_mapping(hwdev, dev_addr, size) && !swiotlb_force)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 return dev_addr;
562
563 /*
564 * Oh well, have to allocate and map a bounce buffer.
565 */
Tony Luck25667d62007-03-06 13:31:45 -0800566 map = map_single(hwdev, ptr, size, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 if (!map) {
568 swiotlb_full(hwdev, size, dir, 1);
569 map = io_tlb_overflow_buffer;
570 }
571
Jan Beulich93fbff62007-02-05 18:49:45 -0800572 dev_addr = virt_to_bus(map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700573
574 /*
575 * Ensure that the address returned is DMA'ble
576 */
FUJITA Tomonori27979822008-09-10 01:06:49 +0900577 if (address_needs_mapping(hwdev, dev_addr, size))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700578 panic("map_single: bounce buffer is not DMA'ble");
579
580 return dev_addr;
581}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700582EXPORT_SYMBOL(swiotlb_map_single_attrs);
583
584dma_addr_t
585swiotlb_map_single(struct device *hwdev, void *ptr, size_t size, int dir)
586{
587 return swiotlb_map_single_attrs(hwdev, ptr, size, dir, NULL);
588}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589
590/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700591 * Unmap a single streaming mode DMA translation. The dma_addr and size must
592 * match what was provided for in a previous swiotlb_map_single call. All
593 * other usages are undefined.
594 *
595 * After this call, reads by the cpu to the buffer are guaranteed to see
596 * whatever the device wrote there.
597 */
598void
Arthur Kepner309df0c2008-04-29 01:00:32 -0700599swiotlb_unmap_single_attrs(struct device *hwdev, dma_addr_t dev_addr,
600 size_t size, int dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601{
Jan Beulich93fbff62007-02-05 18:49:45 -0800602 char *dma_addr = bus_to_virt(dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603
Eric Sesterhenn34814542006-03-24 18:47:11 +0100604 BUG_ON(dir == DMA_NONE);
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900605 if (is_swiotlb_buffer(dma_addr))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 unmap_single(hwdev, dma_addr, size, dir);
607 else if (dir == DMA_FROM_DEVICE)
Jan Beulichcde14bb2007-02-05 18:46:40 -0800608 dma_mark_clean(dma_addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700609}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700610EXPORT_SYMBOL(swiotlb_unmap_single_attrs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611
Arthur Kepner309df0c2008-04-29 01:00:32 -0700612void
613swiotlb_unmap_single(struct device *hwdev, dma_addr_t dev_addr, size_t size,
614 int dir)
615{
616 return swiotlb_unmap_single_attrs(hwdev, dev_addr, size, dir, NULL);
617}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618/*
619 * Make physical memory consistent for a single streaming mode DMA translation
620 * after a transfer.
621 *
622 * If you perform a swiotlb_map_single() but wish to interrogate the buffer
Tony Luck17e5ad62005-09-29 15:52:13 -0700623 * using the cpu, yet do not wish to teardown the dma mapping, you must
624 * call this function before doing so. At the next point you give the dma
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 * address back to the card, you must first perform a
626 * swiotlb_dma_sync_for_device, and then the device again owns the buffer
627 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800628static void
John W. Linville8270f3f2005-09-29 14:43:32 -0700629swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700630 size_t size, int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631{
Jan Beulich93fbff62007-02-05 18:49:45 -0800632 char *dma_addr = bus_to_virt(dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633
Eric Sesterhenn34814542006-03-24 18:47:11 +0100634 BUG_ON(dir == DMA_NONE);
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900635 if (is_swiotlb_buffer(dma_addr))
John W. Linvillede69e0f2005-09-29 14:44:57 -0700636 sync_single(hwdev, dma_addr, size, dir, target);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 else if (dir == DMA_FROM_DEVICE)
Jan Beulichcde14bb2007-02-05 18:46:40 -0800638 dma_mark_clean(dma_addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639}
640
641void
John W. Linville8270f3f2005-09-29 14:43:32 -0700642swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
643 size_t size, int dir)
644{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700645 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700646}
647
648void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
650 size_t size, int dir)
651{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700652 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700653}
654
655/*
John W. Linville878a97c2005-09-29 14:44:23 -0700656 * Same as above, but for a sub-range of the mapping.
657 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800658static void
John W. Linville878a97c2005-09-29 14:44:23 -0700659swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700660 unsigned long offset, size_t size,
661 int dir, int target)
John W. Linville878a97c2005-09-29 14:44:23 -0700662{
Jan Beulich93fbff62007-02-05 18:49:45 -0800663 char *dma_addr = bus_to_virt(dev_addr) + offset;
John W. Linville878a97c2005-09-29 14:44:23 -0700664
Eric Sesterhenn34814542006-03-24 18:47:11 +0100665 BUG_ON(dir == DMA_NONE);
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900666 if (is_swiotlb_buffer(dma_addr))
John W. Linvillede69e0f2005-09-29 14:44:57 -0700667 sync_single(hwdev, dma_addr, size, dir, target);
John W. Linville878a97c2005-09-29 14:44:23 -0700668 else if (dir == DMA_FROM_DEVICE)
Jan Beulichcde14bb2007-02-05 18:46:40 -0800669 dma_mark_clean(dma_addr, size);
John W. Linville878a97c2005-09-29 14:44:23 -0700670}
671
672void
673swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
674 unsigned long offset, size_t size, int dir)
675{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700676 swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
677 SYNC_FOR_CPU);
John W. Linville878a97c2005-09-29 14:44:23 -0700678}
679
680void
681swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
682 unsigned long offset, size_t size, int dir)
683{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700684 swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
685 SYNC_FOR_DEVICE);
John W. Linville878a97c2005-09-29 14:44:23 -0700686}
687
Arthur Kepner309df0c2008-04-29 01:00:32 -0700688void swiotlb_unmap_sg_attrs(struct device *, struct scatterlist *, int, int,
689 struct dma_attrs *);
John W. Linville878a97c2005-09-29 14:44:23 -0700690/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 * Map a set of buffers described by scatterlist in streaming mode for DMA.
692 * This is the scatter-gather version of the above swiotlb_map_single
693 * interface. Here the scatter gather list elements are each tagged with the
694 * appropriate dma address and length. They are obtained via
695 * sg_dma_{address,length}(SG).
696 *
697 * NOTE: An implementation may be able to use a smaller number of
698 * DMA address/length pairs than there are SG table elements.
699 * (for example via virtual mapping capabilities)
700 * The routine returns the number of addr/length pairs actually
701 * used, at most nents.
702 *
703 * Device ownership issues as mentioned above for swiotlb_map_single are the
704 * same here.
705 */
706int
Arthur Kepner309df0c2008-04-29 01:00:32 -0700707swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
708 int dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200710 struct scatterlist *sg;
Tony Luck25667d62007-03-06 13:31:45 -0800711 void *addr;
Jan Beulich563aaf02007-02-05 18:51:25 -0800712 dma_addr_t dev_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 int i;
714
Eric Sesterhenn34814542006-03-24 18:47:11 +0100715 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716
Jens Axboedbfd49f2007-05-11 14:56:18 +0200717 for_each_sg(sgl, sg, nelems, i) {
Tony Luck25667d62007-03-06 13:31:45 -0800718 addr = SG_ENT_VIRT_ADDRESS(sg);
719 dev_addr = virt_to_bus(addr);
FUJITA Tomonori27979822008-09-10 01:06:49 +0900720 if (swiotlb_force ||
721 address_needs_mapping(hwdev, dev_addr, sg->length)) {
Tony Luck25667d62007-03-06 13:31:45 -0800722 void *map = map_single(hwdev, addr, sg->length, dir);
Andi Kleen7e870232005-12-20 14:45:19 +0100723 if (!map) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 /* Don't panic here, we expect map_sg users
725 to do proper error handling. */
726 swiotlb_full(hwdev, sg->length, dir, 0);
Arthur Kepner309df0c2008-04-29 01:00:32 -0700727 swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
728 attrs);
Jens Axboedbfd49f2007-05-11 14:56:18 +0200729 sgl[0].dma_length = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 return 0;
731 }
Jan Beulichcde14bb2007-02-05 18:46:40 -0800732 sg->dma_address = virt_to_bus(map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733 } else
734 sg->dma_address = dev_addr;
735 sg->dma_length = sg->length;
736 }
737 return nelems;
738}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700739EXPORT_SYMBOL(swiotlb_map_sg_attrs);
740
741int
742swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
743 int dir)
744{
745 return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
746}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747
748/*
749 * Unmap a set of streaming mode DMA translations. Again, cpu read rules
750 * concerning calls here are the same as for swiotlb_unmap_single() above.
751 */
752void
Arthur Kepner309df0c2008-04-29 01:00:32 -0700753swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
754 int nelems, int dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200756 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 int i;
758
Eric Sesterhenn34814542006-03-24 18:47:11 +0100759 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700760
Jens Axboedbfd49f2007-05-11 14:56:18 +0200761 for_each_sg(sgl, sg, nelems, i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762 if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
Jan Beulich93fbff62007-02-05 18:49:45 -0800763 unmap_single(hwdev, bus_to_virt(sg->dma_address),
764 sg->dma_length, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700765 else if (dir == DMA_FROM_DEVICE)
Jan Beulichcde14bb2007-02-05 18:46:40 -0800766 dma_mark_clean(SG_ENT_VIRT_ADDRESS(sg), sg->dma_length);
Jens Axboedbfd49f2007-05-11 14:56:18 +0200767 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700768}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700769EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
770
771void
772swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
773 int dir)
774{
775 return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
776}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700777
778/*
779 * Make physical memory consistent for a set of streaming mode DMA translations
780 * after a transfer.
781 *
782 * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
783 * and usage.
784 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800785static void
Jens Axboedbfd49f2007-05-11 14:56:18 +0200786swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700787 int nelems, int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200789 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700790 int i;
791
Eric Sesterhenn34814542006-03-24 18:47:11 +0100792 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793
Jens Axboedbfd49f2007-05-11 14:56:18 +0200794 for_each_sg(sgl, sg, nelems, i) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795 if (sg->dma_address != SG_ENT_PHYS_ADDRESS(sg))
Jan Beulich93fbff62007-02-05 18:49:45 -0800796 sync_single(hwdev, bus_to_virt(sg->dma_address),
John W. Linvillede69e0f2005-09-29 14:44:57 -0700797 sg->dma_length, dir, target);
Jan Beulichcde14bb2007-02-05 18:46:40 -0800798 else if (dir == DMA_FROM_DEVICE)
799 dma_mark_clean(SG_ENT_VIRT_ADDRESS(sg), sg->dma_length);
Jens Axboedbfd49f2007-05-11 14:56:18 +0200800 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700801}
802
803void
John W. Linville8270f3f2005-09-29 14:43:32 -0700804swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
805 int nelems, int dir)
806{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700807 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700808}
809
810void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
812 int nelems, int dir)
813{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700814 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700815}
816
817int
FUJITA Tomonori8d8bb392008-07-25 19:44:49 -0700818swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700819{
Jan Beulich93fbff62007-02-05 18:49:45 -0800820 return (dma_addr == virt_to_bus(io_tlb_overflow_buffer));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821}
822
823/*
Tony Luck17e5ad62005-09-29 15:52:13 -0700824 * Return whether the given device DMA address mask can be supported
Linus Torvalds1da177e2005-04-16 15:20:36 -0700825 * properly. For example, if your device can only drive the low 24-bits
Tony Luck17e5ad62005-09-29 15:52:13 -0700826 * during bus mastering, then you would pass 0x00ffffff as the mask to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 * this function.
828 */
829int
Jan Beulich563aaf02007-02-05 18:51:25 -0800830swiotlb_dma_supported(struct device *hwdev, u64 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700831{
Tony Luck25667d62007-03-06 13:31:45 -0800832 return virt_to_bus(io_tlb_end - 1) <= mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833}
834
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835EXPORT_SYMBOL(swiotlb_map_single);
836EXPORT_SYMBOL(swiotlb_unmap_single);
837EXPORT_SYMBOL(swiotlb_map_sg);
838EXPORT_SYMBOL(swiotlb_unmap_sg);
839EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
840EXPORT_SYMBOL(swiotlb_sync_single_for_device);
John W. Linville878a97c2005-09-29 14:44:23 -0700841EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu);
842EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700843EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
844EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
845EXPORT_SYMBOL(swiotlb_dma_mapping_error);
Tony Luck25667d62007-03-06 13:31:45 -0800846EXPORT_SYMBOL(swiotlb_alloc_coherent);
847EXPORT_SYMBOL(swiotlb_free_coherent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848EXPORT_SYMBOL(swiotlb_dma_supported);