blob: cba3db809fbc4e0dc9f07cda8ed3ed3bda47cc90 [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.
Becky Brucefb05a372008-12-22 10:26:09 -080017 * 08/12/11 beckyb Add highmem support
Linus Torvalds1da177e2005-04-16 15:20:36 -070018 */
19
20#include <linux/cache.h>
Tony Luck17e5ad62005-09-29 15:52:13 -070021#include <linux/dma-mapping.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022#include <linux/mm.h>
23#include <linux/module.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/spinlock.h>
25#include <linux/string.h>
Ian Campbell0016fde2008-12-16 12:17:27 -080026#include <linux/swiotlb.h>
Becky Brucefb05a372008-12-22 10:26:09 -080027#include <linux/pfn.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070028#include <linux/types.h>
29#include <linux/ctype.h>
Jeremy Fitzhardingeef9b1892008-12-16 12:17:33 -080030#include <linux/highmem.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070031
32#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <asm/dma.h>
Tony Luck17e5ad62005-09-29 15:52:13 -070034#include <asm/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
36#include <linux/init.h>
37#include <linux/bootmem.h>
FUJITA Tomonoria8522502008-04-29 00:59:36 -070038#include <linux/iommu-helper.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070039
40#define OFFSET(val,align) ((unsigned long) \
41 ( (val) & ( (align) - 1)))
42
Alex Williamson0b9afed2005-09-06 11:20:49 -060043#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
44
45/*
46 * Minimum IO TLB size to bother booting with. Systems with mainly
47 * 64bit capable cards will only lightly use the swiotlb. If we can't
48 * allocate a contiguous 1MB, we're probably in trouble anyway.
49 */
50#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
51
John W. Linvillede69e0f2005-09-29 14:44:57 -070052/*
53 * Enumeration for sync targets
54 */
55enum dma_sync_target {
56 SYNC_FOR_CPU = 0,
57 SYNC_FOR_DEVICE = 1,
58};
59
Linus Torvalds1da177e2005-04-16 15:20:36 -070060int swiotlb_force;
61
62/*
Becky Bruceceb5ac32009-04-08 09:09:15 -050063 * Used to do a quick range check in unmap_single and
64 * sync_single_*, to see if the memory was in fact allocated by this
Linus Torvalds1da177e2005-04-16 15:20:36 -070065 * API.
66 */
67static char *io_tlb_start, *io_tlb_end;
68
69/*
70 * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
71 * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
72 */
73static unsigned long io_tlb_nslabs;
74
75/*
76 * When the IOMMU overflows we return a fallback buffer. This sets the size.
77 */
78static unsigned long io_tlb_overflow = 32*1024;
79
80void *io_tlb_overflow_buffer;
81
82/*
83 * This is a free list describing the number of free entries available from
84 * each index
85 */
86static unsigned int *io_tlb_list;
87static unsigned int io_tlb_index;
88
89/*
90 * We need to save away the original address corresponding to a mapped entry
91 * for the sync operations.
92 */
Becky Brucebc40ac62008-12-22 10:26:08 -080093static phys_addr_t *io_tlb_orig_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
95/*
96 * Protect the above data structures in the map and unmap calls
97 */
98static DEFINE_SPINLOCK(io_tlb_lock);
99
100static int __init
101setup_io_tlb_npages(char *str)
102{
103 if (isdigit(*str)) {
Alex Williamsone8579e72005-08-04 13:06:00 -0700104 io_tlb_nslabs = simple_strtoul(str, &str, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700105 /* avoid tail segment of size < IO_TLB_SEGSIZE */
106 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
107 }
108 if (*str == ',')
109 ++str;
110 if (!strcmp(str, "force"))
111 swiotlb_force = 1;
112 return 1;
113}
114__setup("swiotlb=", setup_io_tlb_npages);
115/* make io_tlb_overflow tunable too? */
116
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800117dma_addr_t __weak swiotlb_phys_to_bus(struct device *hwdev, phys_addr_t paddr)
Ian Campbelle08e1f72008-12-16 12:17:30 -0800118{
119 return paddr;
120}
121
Becky Bruce42d7c5e2009-04-08 09:09:21 -0500122phys_addr_t __weak swiotlb_bus_to_phys(struct device *hwdev, dma_addr_t baddr)
Ian Campbelle08e1f72008-12-16 12:17:30 -0800123{
124 return baddr;
125}
126
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900127/* Note that this doesn't work with highmem page */
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800128static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
129 volatile void *address)
Ian Campbelle08e1f72008-12-16 12:17:30 -0800130{
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800131 return swiotlb_phys_to_bus(hwdev, virt_to_phys(address));
Ian Campbelle08e1f72008-12-16 12:17:30 -0800132}
133
Becky Bruceef5722f2009-04-08 09:09:18 -0500134int __weak swiotlb_arch_address_needs_mapping(struct device *hwdev,
135 dma_addr_t addr, size_t size)
136{
137 return !is_buffer_dma_capable(dma_get_mask(hwdev), addr, size);
138}
139
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800140static void swiotlb_print_info(unsigned long bytes)
141{
142 phys_addr_t pstart, pend;
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800143
144 pstart = virt_to_phys(io_tlb_start);
145 pend = virt_to_phys(io_tlb_end);
146
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800147 printk(KERN_INFO "Placing %luMB software IO TLB between %p - %p\n",
148 bytes >> 20, io_tlb_start, io_tlb_end);
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800149 printk(KERN_INFO "software IO TLB at phys %#llx - %#llx\n",
150 (unsigned long long)pstart,
151 (unsigned long long)pend);
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800152}
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154/*
155 * Statically reserve bounce buffer space and initialize bounce buffer data
Tony Luck17e5ad62005-09-29 15:52:13 -0700156 * structures for the software IO TLB used to implement the DMA API.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700157 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800158void __init
159swiotlb_init_with_default_size(size_t default_size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160{
Jan Beulich563aaf02007-02-05 18:51:25 -0800161 unsigned long i, bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
163 if (!io_tlb_nslabs) {
Alex Williamsone8579e72005-08-04 13:06:00 -0700164 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700165 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
166 }
167
Jan Beulich563aaf02007-02-05 18:51:25 -0800168 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
169
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 /*
171 * Get IO TLB memory from the low pages
172 */
FUJITA Tomonori38851232009-07-10 10:04:50 +0900173 io_tlb_start = alloc_bootmem_low_pages(bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 if (!io_tlb_start)
175 panic("Cannot allocate SWIOTLB buffer");
Jan Beulich563aaf02007-02-05 18:51:25 -0800176 io_tlb_end = io_tlb_start + bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700177
178 /*
179 * Allocate and initialize the free list array. This array is used
180 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
181 * between io_tlb_start and io_tlb_end.
182 */
183 io_tlb_list = alloc_bootmem(io_tlb_nslabs * sizeof(int));
Tony Luck25667d62007-03-06 13:31:45 -0800184 for (i = 0; i < io_tlb_nslabs; i++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
186 io_tlb_index = 0;
Becky Brucebc40ac62008-12-22 10:26:08 -0800187 io_tlb_orig_addr = alloc_bootmem(io_tlb_nslabs * sizeof(phys_addr_t));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188
189 /*
190 * Get the overflow emergency buffer
191 */
192 io_tlb_overflow_buffer = alloc_bootmem_low(io_tlb_overflow);
Jan Beulich563aaf02007-02-05 18:51:25 -0800193 if (!io_tlb_overflow_buffer)
194 panic("Cannot allocate SWIOTLB overflow buffer!\n");
195
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800196 swiotlb_print_info(bytes);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700197}
198
Jan Beulich563aaf02007-02-05 18:51:25 -0800199void __init
200swiotlb_init(void)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700201{
Tony Luck25667d62007-03-06 13:31:45 -0800202 swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700203}
204
Alex Williamson0b9afed2005-09-06 11:20:49 -0600205/*
206 * Systems with larger DMA zones (those that don't support ISA) can
207 * initialize the swiotlb later using the slab allocator if needed.
208 * This should be just like above, but with some error catching.
209 */
210int
Jan Beulich563aaf02007-02-05 18:51:25 -0800211swiotlb_late_init_with_default_size(size_t default_size)
Alex Williamson0b9afed2005-09-06 11:20:49 -0600212{
Jan Beulich563aaf02007-02-05 18:51:25 -0800213 unsigned long i, bytes, req_nslabs = io_tlb_nslabs;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600214 unsigned int order;
215
216 if (!io_tlb_nslabs) {
217 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
218 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
219 }
220
221 /*
222 * Get IO TLB memory from the low pages
223 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800224 order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600225 io_tlb_nslabs = SLABS_PER_PAGE << order;
Jan Beulich563aaf02007-02-05 18:51:25 -0800226 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600227
228 while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
FUJITA Tomonoribb521962009-07-10 10:04:51 +0900229 io_tlb_start = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
230 order);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600231 if (io_tlb_start)
232 break;
233 order--;
234 }
235
236 if (!io_tlb_start)
237 goto cleanup1;
238
Jan Beulich563aaf02007-02-05 18:51:25 -0800239 if (order != get_order(bytes)) {
Alex Williamson0b9afed2005-09-06 11:20:49 -0600240 printk(KERN_WARNING "Warning: only able to allocate %ld MB "
241 "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
242 io_tlb_nslabs = SLABS_PER_PAGE << order;
Jan Beulich563aaf02007-02-05 18:51:25 -0800243 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600244 }
Jan Beulich563aaf02007-02-05 18:51:25 -0800245 io_tlb_end = io_tlb_start + bytes;
246 memset(io_tlb_start, 0, bytes);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600247
248 /*
249 * Allocate and initialize the free list array. This array is used
250 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
251 * between io_tlb_start and io_tlb_end.
252 */
253 io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
254 get_order(io_tlb_nslabs * sizeof(int)));
255 if (!io_tlb_list)
256 goto cleanup2;
257
258 for (i = 0; i < io_tlb_nslabs; i++)
259 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
260 io_tlb_index = 0;
261
Becky Brucebc40ac62008-12-22 10:26:08 -0800262 io_tlb_orig_addr = (phys_addr_t *)
263 __get_free_pages(GFP_KERNEL,
264 get_order(io_tlb_nslabs *
265 sizeof(phys_addr_t)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600266 if (!io_tlb_orig_addr)
267 goto cleanup3;
268
Becky Brucebc40ac62008-12-22 10:26:08 -0800269 memset(io_tlb_orig_addr, 0, io_tlb_nslabs * sizeof(phys_addr_t));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600270
271 /*
272 * Get the overflow emergency buffer
273 */
274 io_tlb_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
275 get_order(io_tlb_overflow));
276 if (!io_tlb_overflow_buffer)
277 goto cleanup4;
278
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800279 swiotlb_print_info(bytes);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600280
281 return 0;
282
283cleanup4:
Becky Brucebc40ac62008-12-22 10:26:08 -0800284 free_pages((unsigned long)io_tlb_orig_addr,
285 get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600286 io_tlb_orig_addr = NULL;
287cleanup3:
Tony Luck25667d62007-03-06 13:31:45 -0800288 free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
289 sizeof(int)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600290 io_tlb_list = NULL;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600291cleanup2:
Jan Beulich563aaf02007-02-05 18:51:25 -0800292 io_tlb_end = NULL;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600293 free_pages((unsigned long)io_tlb_start, order);
294 io_tlb_start = NULL;
295cleanup1:
296 io_tlb_nslabs = req_nslabs;
297 return -ENOMEM;
298}
299
Becky Bruceef5722f2009-04-08 09:09:18 -0500300static inline int
FUJITA Tomonori27979822008-09-10 01:06:49 +0900301address_needs_mapping(struct device *hwdev, dma_addr_t addr, size_t size)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700302{
Becky Bruceef5722f2009-04-08 09:09:18 -0500303 return swiotlb_arch_address_needs_mapping(hwdev, addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304}
305
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900306static int is_swiotlb_buffer(phys_addr_t paddr)
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900307{
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900308 return paddr >= virt_to_phys(io_tlb_start) &&
309 paddr < virt_to_phys(io_tlb_end);
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900310}
311
Linus Torvalds1da177e2005-04-16 15:20:36 -0700312/*
Becky Brucefb05a372008-12-22 10:26:09 -0800313 * Bounce: copy the swiotlb buffer back to the original dma location
314 */
315static void swiotlb_bounce(phys_addr_t phys, char *dma_addr, size_t size,
316 enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317{
Becky Brucefb05a372008-12-22 10:26:09 -0800318 unsigned long pfn = PFN_DOWN(phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700319
Becky Brucefb05a372008-12-22 10:26:09 -0800320 if (PageHighMem(pfn_to_page(pfn))) {
321 /* The buffer does not have a mapping. Map it in and copy */
322 unsigned int offset = phys & ~PAGE_MASK;
323 char *buffer;
324 unsigned int sz = 0;
325 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700326
Becky Brucefb05a372008-12-22 10:26:09 -0800327 while (size) {
Becky Bruce67131ad2009-04-08 09:09:16 -0500328 sz = min_t(size_t, PAGE_SIZE - offset, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329
Becky Brucefb05a372008-12-22 10:26:09 -0800330 local_irq_save(flags);
331 buffer = kmap_atomic(pfn_to_page(pfn),
332 KM_BOUNCE_READ);
333 if (dir == DMA_TO_DEVICE)
334 memcpy(dma_addr, buffer + offset, sz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 else
Becky Brucefb05a372008-12-22 10:26:09 -0800336 memcpy(buffer + offset, dma_addr, sz);
337 kunmap_atomic(buffer, KM_BOUNCE_READ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 local_irq_restore(flags);
Becky Brucefb05a372008-12-22 10:26:09 -0800339
340 size -= sz;
341 pfn++;
342 dma_addr += sz;
343 offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 }
345 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700346 if (dir == DMA_TO_DEVICE)
Becky Brucefb05a372008-12-22 10:26:09 -0800347 memcpy(dma_addr, phys_to_virt(phys), size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 else
Becky Brucefb05a372008-12-22 10:26:09 -0800349 memcpy(phys_to_virt(phys), dma_addr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 }
351}
352
353/*
354 * Allocates bounce buffer and returns its kernel virtual address.
355 */
356static void *
Becky Brucebc40ac62008-12-22 10:26:08 -0800357map_single(struct device *hwdev, phys_addr_t phys, size_t size, int dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358{
359 unsigned long flags;
360 char *dma_addr;
361 unsigned int nslots, stride, index, wrap;
362 int i;
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800363 unsigned long start_dma_addr;
364 unsigned long mask;
365 unsigned long offset_slots;
366 unsigned long max_slots;
367
368 mask = dma_get_seg_boundary(hwdev);
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800369 start_dma_addr = swiotlb_virt_to_bus(hwdev, io_tlb_start) & mask;
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800370
371 offset_slots = ALIGN(start_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
Ian Campbella5ddde4a2008-12-16 12:17:29 -0800372
373 /*
374 * Carefully handle integer overflow which can occur when mask == ~0UL.
375 */
Jan Beulichb15a38912008-03-13 09:13:30 +0000376 max_slots = mask + 1
377 ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
378 : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379
380 /*
381 * For mappings greater than a page, we limit the stride (and
382 * hence alignment) to a page size.
383 */
384 nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
385 if (size > PAGE_SIZE)
386 stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
387 else
388 stride = 1;
389
Eric Sesterhenn34814542006-03-24 18:47:11 +0100390 BUG_ON(!nslots);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391
392 /*
393 * Find suitable number of IO TLB entries size that will fit this
394 * request and allocate a buffer from that IO TLB pool.
395 */
396 spin_lock_irqsave(&io_tlb_lock, flags);
Andrew Mortona7133a12008-04-29 00:59:36 -0700397 index = ALIGN(io_tlb_index, stride);
398 if (index >= io_tlb_nslabs)
399 index = 0;
400 wrap = index;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401
Andrew Mortona7133a12008-04-29 00:59:36 -0700402 do {
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700403 while (iommu_is_span_boundary(index, nslots, offset_slots,
404 max_slots)) {
Jan Beulichb15a38912008-03-13 09:13:30 +0000405 index += stride;
406 if (index >= io_tlb_nslabs)
407 index = 0;
Andrew Mortona7133a12008-04-29 00:59:36 -0700408 if (index == wrap)
409 goto not_found;
410 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700411
Andrew Mortona7133a12008-04-29 00:59:36 -0700412 /*
413 * If we find a slot that indicates we have 'nslots' number of
414 * contiguous buffers, we allocate the buffers from that slot
415 * and mark the entries as '0' indicating unavailable.
416 */
417 if (io_tlb_list[index] >= nslots) {
418 int count = 0;
419
420 for (i = index; i < (int) (index + nslots); i++)
421 io_tlb_list[i] = 0;
422 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
423 io_tlb_list[i] = ++count;
424 dma_addr = io_tlb_start + (index << IO_TLB_SHIFT);
425
426 /*
427 * Update the indices to avoid searching in the next
428 * round.
429 */
430 io_tlb_index = ((index + nslots) < io_tlb_nslabs
431 ? (index + nslots) : 0);
432
433 goto found;
434 }
435 index += stride;
436 if (index >= io_tlb_nslabs)
437 index = 0;
438 } while (index != wrap);
439
440not_found:
441 spin_unlock_irqrestore(&io_tlb_lock, flags);
442 return NULL;
443found:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 spin_unlock_irqrestore(&io_tlb_lock, flags);
445
446 /*
447 * Save away the mapping from the original address to the DMA address.
448 * This is needed when we sync the memory. Then we sync the buffer if
449 * needed.
450 */
Becky Brucebc40ac62008-12-22 10:26:08 -0800451 for (i = 0; i < nslots; i++)
452 io_tlb_orig_addr[index+i] = phys + (i << IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
Becky Brucefb05a372008-12-22 10:26:09 -0800454 swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455
456 return dma_addr;
457}
458
459/*
460 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
461 */
462static void
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500463do_unmap_single(struct device *hwdev, char *dma_addr, size_t size, int dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464{
465 unsigned long flags;
466 int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
467 int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
Becky Brucebc40ac62008-12-22 10:26:08 -0800468 phys_addr_t phys = io_tlb_orig_addr[index];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470 /*
471 * First, sync the memory before unmapping the entry
472 */
Becky Brucebc40ac62008-12-22 10:26:08 -0800473 if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
Becky Brucefb05a372008-12-22 10:26:09 -0800474 swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475
476 /*
477 * Return the buffer to the free list by setting the corresponding
478 * entries to indicate the number of contigous entries available.
479 * While returning the entries to the free list, we merge the entries
480 * with slots below and above the pool being returned.
481 */
482 spin_lock_irqsave(&io_tlb_lock, flags);
483 {
484 count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
485 io_tlb_list[index + nslots] : 0);
486 /*
487 * Step 1: return the slots to the free list, merging the
488 * slots with superceeding slots
489 */
490 for (i = index + nslots - 1; i >= index; i--)
491 io_tlb_list[i] = ++count;
492 /*
493 * Step 2: merge the returned slots with the preceding slots,
494 * if available (non zero)
495 */
496 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
497 io_tlb_list[i] = ++count;
498 }
499 spin_unlock_irqrestore(&io_tlb_lock, flags);
500}
501
502static void
John W. Linvillede69e0f2005-09-29 14:44:57 -0700503sync_single(struct device *hwdev, char *dma_addr, size_t size,
504 int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505{
Becky Brucebc40ac62008-12-22 10:26:08 -0800506 int index = (dma_addr - io_tlb_start) >> IO_TLB_SHIFT;
507 phys_addr_t phys = io_tlb_orig_addr[index];
508
509 phys += ((unsigned long)dma_addr & ((1 << IO_TLB_SHIFT) - 1));
Keir Fraserdf336d12007-07-21 04:37:24 -0700510
John W. Linvillede69e0f2005-09-29 14:44:57 -0700511 switch (target) {
512 case SYNC_FOR_CPU:
513 if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
Becky Brucefb05a372008-12-22 10:26:09 -0800514 swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100515 else
516 BUG_ON(dir != DMA_TO_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700517 break;
518 case SYNC_FOR_DEVICE:
519 if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
Becky Brucefb05a372008-12-22 10:26:09 -0800520 swiotlb_bounce(phys, dma_addr, size, DMA_TO_DEVICE);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100521 else
522 BUG_ON(dir != DMA_FROM_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700523 break;
524 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700525 BUG();
John W. Linvillede69e0f2005-09-29 14:44:57 -0700526 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700527}
528
529void *
530swiotlb_alloc_coherent(struct device *hwdev, size_t size,
Al Viro06a54492005-10-21 03:21:03 -0400531 dma_addr_t *dma_handle, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532{
Jan Beulich563aaf02007-02-05 18:51:25 -0800533 dma_addr_t dev_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 void *ret;
535 int order = get_order(size);
Yang Hongyang284901a2009-04-06 19:01:15 -0700536 u64 dma_mask = DMA_BIT_MASK(32);
FUJITA Tomonori1e74f302008-11-17 16:24:34 +0900537
538 if (hwdev && hwdev->coherent_dma_mask)
539 dma_mask = hwdev->coherent_dma_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540
Tony Luck25667d62007-03-06 13:31:45 -0800541 ret = (void *)__get_free_pages(flags, order);
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800542 if (ret &&
543 !is_buffer_dma_capable(dma_mask, swiotlb_virt_to_bus(hwdev, ret),
544 size)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700545 /*
546 * The allocated memory isn't reachable by the device.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 */
548 free_pages((unsigned long) ret, order);
549 ret = NULL;
550 }
551 if (!ret) {
552 /*
553 * We are either out of memory or the device can't DMA
Becky Bruceceb5ac32009-04-08 09:09:15 -0500554 * to GFP_DMA memory; fall back on map_single(), which
555 * will grab memory from the lowest available address range.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700556 */
Becky Brucebc40ac62008-12-22 10:26:08 -0800557 ret = map_single(hwdev, 0, size, DMA_FROM_DEVICE);
FUJITA Tomonori9dfda122008-09-08 18:53:48 +0900558 if (!ret)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700559 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 }
561
562 memset(ret, 0, size);
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800563 dev_addr = swiotlb_virt_to_bus(hwdev, ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700564
565 /* Confirm address can be DMA'd by device */
FUJITA Tomonori1e74f302008-11-17 16:24:34 +0900566 if (!is_buffer_dma_capable(dma_mask, dev_addr, size)) {
Jan Beulich563aaf02007-02-05 18:51:25 -0800567 printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
FUJITA Tomonori1e74f302008-11-17 16:24:34 +0900568 (unsigned long long)dma_mask,
Jan Beulich563aaf02007-02-05 18:51:25 -0800569 (unsigned long long)dev_addr);
FUJITA Tomonoria2b89b52008-10-23 18:42:03 +0900570
571 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500572 do_unmap_single(hwdev, ret, size, DMA_TO_DEVICE);
FUJITA Tomonoria2b89b52008-10-23 18:42:03 +0900573 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 }
575 *dma_handle = dev_addr;
576 return ret;
577}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900578EXPORT_SYMBOL(swiotlb_alloc_coherent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579
580void
581swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900582 dma_addr_t dev_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583{
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900584 phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
585
David Brownellaa248862007-08-10 13:10:27 -0700586 WARN_ON(irqs_disabled());
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900587 if (!is_swiotlb_buffer(paddr))
588 free_pages((unsigned long)vaddr, get_order(size));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 else
590 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500591 do_unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700592}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900593EXPORT_SYMBOL(swiotlb_free_coherent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700594
595static void
596swiotlb_full(struct device *dev, size_t size, int dir, int do_panic)
597{
598 /*
599 * Ran out of IOMMU space for this operation. This is very bad.
600 * Unfortunately the drivers cannot handle this operation properly.
Tony Luck17e5ad62005-09-29 15:52:13 -0700601 * unless they check for dma_mapping_error (most don't)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700602 * When the mapping is small enough return a static buffer to limit
603 * the damage, or panic when the transfer is too big.
604 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800605 printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
Kay Sievers94b32482009-01-06 10:44:37 -0800606 "device %s\n", size, dev ? dev_name(dev) : "?");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700607
608 if (size > io_tlb_overflow && do_panic) {
Tony Luck17e5ad62005-09-29 15:52:13 -0700609 if (dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL)
610 panic("DMA: Memory would be corrupted\n");
611 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
612 panic("DMA: Random memory would be DMAed\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 }
614}
615
616/*
617 * Map a single buffer of the indicated size for DMA in streaming mode. The
Tony Luck17e5ad62005-09-29 15:52:13 -0700618 * physical address to use is returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700619 *
620 * Once the device is given the dma address, the device owns this memory until
Becky Bruceceb5ac32009-04-08 09:09:15 -0500621 * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700622 */
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900623dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
624 unsigned long offset, size_t size,
625 enum dma_data_direction dir,
626 struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627{
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900628 phys_addr_t phys = page_to_phys(page) + offset;
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900629 dma_addr_t dev_addr = swiotlb_phys_to_bus(dev, phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 void *map;
631
Eric Sesterhenn34814542006-03-24 18:47:11 +0100632 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 /*
Becky Bruceceb5ac32009-04-08 09:09:15 -0500634 * If the address happens to be in the device's DMA window,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635 * we can safely return the device addr and not worry about bounce
636 * buffering it.
637 */
FUJITA Tomonoricf56e3f2009-07-10 10:04:52 +0900638 if (!address_needs_mapping(dev, dev_addr, size) && !swiotlb_force)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639 return dev_addr;
640
641 /*
642 * Oh well, have to allocate and map a bounce buffer.
643 */
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900644 map = map_single(dev, phys, size, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645 if (!map) {
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900646 swiotlb_full(dev, size, dir, 1);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 map = io_tlb_overflow_buffer;
648 }
649
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900650 dev_addr = swiotlb_virt_to_bus(dev, map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651
652 /*
653 * Ensure that the address returned is DMA'ble
654 */
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900655 if (address_needs_mapping(dev, dev_addr, size))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700656 panic("map_single: bounce buffer is not DMA'ble");
657
658 return dev_addr;
659}
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900660EXPORT_SYMBOL_GPL(swiotlb_map_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661
662/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663 * Unmap a single streaming mode DMA translation. The dma_addr and size must
Becky Bruceceb5ac32009-04-08 09:09:15 -0500664 * match what was provided for in a previous swiotlb_map_page call. All
Linus Torvalds1da177e2005-04-16 15:20:36 -0700665 * other usages are undefined.
666 *
667 * After this call, reads by the cpu to the buffer are guaranteed to see
668 * whatever the device wrote there.
669 */
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500670static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
671 size_t size, int dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672{
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900673 phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674
Eric Sesterhenn34814542006-03-24 18:47:11 +0100675 BUG_ON(dir == DMA_NONE);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500676
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900677 if (is_swiotlb_buffer(paddr)) {
678 do_unmap_single(hwdev, phys_to_virt(paddr), size, dir);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500679 return;
680 }
681
682 if (dir != DMA_FROM_DEVICE)
683 return;
684
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900685 /*
686 * phys_to_virt doesn't work with hihgmem page but we could
687 * call dma_mark_clean() with hihgmem page here. However, we
688 * are fine since dma_mark_clean() is null on POWERPC. We can
689 * make dma_mark_clean() take a physical address if necessary.
690 */
691 dma_mark_clean(phys_to_virt(paddr), size);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500692}
693
694void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
695 size_t size, enum dma_data_direction dir,
696 struct dma_attrs *attrs)
697{
698 unmap_single(hwdev, dev_addr, size, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699}
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900700EXPORT_SYMBOL_GPL(swiotlb_unmap_page);
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900701
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702/*
703 * Make physical memory consistent for a single streaming mode DMA translation
704 * after a transfer.
705 *
Becky Bruceceb5ac32009-04-08 09:09:15 -0500706 * If you perform a swiotlb_map_page() but wish to interrogate the buffer
Tony Luck17e5ad62005-09-29 15:52:13 -0700707 * using the cpu, yet do not wish to teardown the dma mapping, you must
708 * call this function before doing so. At the next point you give the dma
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 * address back to the card, you must first perform a
710 * swiotlb_dma_sync_for_device, and then the device again owns the buffer
711 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800712static void
John W. Linville8270f3f2005-09-29 14:43:32 -0700713swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700714 size_t size, int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715{
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900716 phys_addr_t paddr = swiotlb_bus_to_phys(hwdev, dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700717
Eric Sesterhenn34814542006-03-24 18:47:11 +0100718 BUG_ON(dir == DMA_NONE);
Becky Bruce380d6872009-04-08 09:09:20 -0500719
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900720 if (is_swiotlb_buffer(paddr)) {
721 sync_single(hwdev, phys_to_virt(paddr), size, dir, target);
Becky Bruce380d6872009-04-08 09:09:20 -0500722 return;
723 }
724
725 if (dir != DMA_FROM_DEVICE)
726 return;
727
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900728 dma_mark_clean(phys_to_virt(paddr), size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700729}
730
731void
John W. Linville8270f3f2005-09-29 14:43:32 -0700732swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900733 size_t size, enum dma_data_direction dir)
John W. Linville8270f3f2005-09-29 14:43:32 -0700734{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700735 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700736}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900737EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
John W. Linville8270f3f2005-09-29 14:43:32 -0700738
739void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900741 size_t size, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700743 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700744}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900745EXPORT_SYMBOL(swiotlb_sync_single_for_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746
747/*
John W. Linville878a97c2005-09-29 14:44:23 -0700748 * Same as above, but for a sub-range of the mapping.
749 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800750static void
John W. Linville878a97c2005-09-29 14:44:23 -0700751swiotlb_sync_single_range(struct device *hwdev, dma_addr_t dev_addr,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700752 unsigned long offset, size_t size,
753 int dir, int target)
John W. Linville878a97c2005-09-29 14:44:23 -0700754{
Becky Bruce380d6872009-04-08 09:09:20 -0500755 swiotlb_sync_single(hwdev, dev_addr + offset, size, dir, target);
John W. Linville878a97c2005-09-29 14:44:23 -0700756}
757
758void
759swiotlb_sync_single_range_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900760 unsigned long offset, size_t size,
761 enum dma_data_direction dir)
John W. Linville878a97c2005-09-29 14:44:23 -0700762{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700763 swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
764 SYNC_FOR_CPU);
John W. Linville878a97c2005-09-29 14:44:23 -0700765}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900766EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu);
John W. Linville878a97c2005-09-29 14:44:23 -0700767
768void
769swiotlb_sync_single_range_for_device(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900770 unsigned long offset, size_t size,
771 enum dma_data_direction dir)
John W. Linville878a97c2005-09-29 14:44:23 -0700772{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700773 swiotlb_sync_single_range(hwdev, dev_addr, offset, size, dir,
774 SYNC_FOR_DEVICE);
John W. Linville878a97c2005-09-29 14:44:23 -0700775}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900776EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device);
John W. Linville878a97c2005-09-29 14:44:23 -0700777
778/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 * Map a set of buffers described by scatterlist in streaming mode for DMA.
Becky Bruceceb5ac32009-04-08 09:09:15 -0500780 * This is the scatter-gather version of the above swiotlb_map_page
Linus Torvalds1da177e2005-04-16 15:20:36 -0700781 * interface. Here the scatter gather list elements are each tagged with the
782 * appropriate dma address and length. They are obtained via
783 * sg_dma_{address,length}(SG).
784 *
785 * NOTE: An implementation may be able to use a smaller number of
786 * DMA address/length pairs than there are SG table elements.
787 * (for example via virtual mapping capabilities)
788 * The routine returns the number of addr/length pairs actually
789 * used, at most nents.
790 *
Becky Bruceceb5ac32009-04-08 09:09:15 -0500791 * Device ownership issues as mentioned above for swiotlb_map_page are the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792 * same here.
793 */
794int
Arthur Kepner309df0c2008-04-29 01:00:32 -0700795swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900796 enum dma_data_direction dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700797{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200798 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 int i;
800
Eric Sesterhenn34814542006-03-24 18:47:11 +0100801 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802
Jens Axboedbfd49f2007-05-11 14:56:18 +0200803 for_each_sg(sgl, sg, nelems, i) {
Ian Campbell961d7d02009-01-09 18:32:10 +0000804 phys_addr_t paddr = sg_phys(sg);
805 dma_addr_t dev_addr = swiotlb_phys_to_bus(hwdev, paddr);
Becky Brucebc40ac62008-12-22 10:26:08 -0800806
FUJITA Tomonoricf56e3f2009-07-10 10:04:52 +0900807 if (swiotlb_force ||
FUJITA Tomonori27979822008-09-10 01:06:49 +0900808 address_needs_mapping(hwdev, dev_addr, sg->length)) {
Becky Brucebc40ac62008-12-22 10:26:08 -0800809 void *map = map_single(hwdev, sg_phys(sg),
810 sg->length, dir);
Andi Kleen7e870232005-12-20 14:45:19 +0100811 if (!map) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 /* Don't panic here, we expect map_sg users
813 to do proper error handling. */
814 swiotlb_full(hwdev, sg->length, dir, 0);
Arthur Kepner309df0c2008-04-29 01:00:32 -0700815 swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
816 attrs);
Jens Axboedbfd49f2007-05-11 14:56:18 +0200817 sgl[0].dma_length = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 return 0;
819 }
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800820 sg->dma_address = swiotlb_virt_to_bus(hwdev, map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700821 } else
822 sg->dma_address = dev_addr;
823 sg->dma_length = sg->length;
824 }
825 return nelems;
826}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700827EXPORT_SYMBOL(swiotlb_map_sg_attrs);
828
829int
830swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
831 int dir)
832{
833 return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, NULL);
834}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900835EXPORT_SYMBOL(swiotlb_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836
837/*
838 * Unmap a set of streaming mode DMA translations. Again, cpu read rules
Becky Bruceceb5ac32009-04-08 09:09:15 -0500839 * concerning calls here are the same as for swiotlb_unmap_page() above.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840 */
841void
Arthur Kepner309df0c2008-04-29 01:00:32 -0700842swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900843 int nelems, enum dma_data_direction dir, struct dma_attrs *attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200845 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 int i;
847
Eric Sesterhenn34814542006-03-24 18:47:11 +0100848 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500850 for_each_sg(sgl, sg, nelems, i)
851 unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
852
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700854EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
855
856void
857swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
858 int dir)
859{
860 return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, NULL);
861}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900862EXPORT_SYMBOL(swiotlb_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863
864/*
865 * Make physical memory consistent for a set of streaming mode DMA translations
866 * after a transfer.
867 *
868 * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
869 * and usage.
870 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800871static void
Jens Axboedbfd49f2007-05-11 14:56:18 +0200872swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700873 int nelems, int dir, int target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200875 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876 int i;
877
Becky Bruce380d6872009-04-08 09:09:20 -0500878 for_each_sg(sgl, sg, nelems, i)
879 swiotlb_sync_single(hwdev, sg->dma_address,
John W. Linvillede69e0f2005-09-29 14:44:57 -0700880 sg->dma_length, dir, target);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700881}
882
883void
John W. Linville8270f3f2005-09-29 14:43:32 -0700884swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900885 int nelems, enum dma_data_direction dir)
John W. Linville8270f3f2005-09-29 14:43:32 -0700886{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700887 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700888}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900889EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
John W. Linville8270f3f2005-09-29 14:43:32 -0700890
891void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700892swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900893 int nelems, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700895 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700896}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900897EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898
899int
FUJITA Tomonori8d8bb392008-07-25 19:44:49 -0700900swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700901{
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800902 return (dma_addr == swiotlb_virt_to_bus(hwdev, io_tlb_overflow_buffer));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900904EXPORT_SYMBOL(swiotlb_dma_mapping_error);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905
906/*
Tony Luck17e5ad62005-09-29 15:52:13 -0700907 * Return whether the given device DMA address mask can be supported
Linus Torvalds1da177e2005-04-16 15:20:36 -0700908 * properly. For example, if your device can only drive the low 24-bits
Tony Luck17e5ad62005-09-29 15:52:13 -0700909 * during bus mastering, then you would pass 0x00ffffff as the mask to
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910 * this function.
911 */
912int
Jan Beulich563aaf02007-02-05 18:51:25 -0800913swiotlb_dma_supported(struct device *hwdev, u64 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700914{
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800915 return swiotlb_virt_to_bus(hwdev, io_tlb_end - 1) <= mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700917EXPORT_SYMBOL(swiotlb_dma_supported);