blob: ad1d2962d129cb7ea673edc0bb02e753529f9289 [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>
Paul Gortmaker8bc3bcc2011-11-16 21:29:17 -050023#include <linux/export.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>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090031#include <linux/gfp.h>
Christoph Hellwig84be4562015-05-01 12:46:15 +020032#include <linux/scatterlist.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070035#include <asm/dma.h>
36
37#include <linux/init.h>
38#include <linux/bootmem.h>
FUJITA Tomonoria8522502008-04-29 00:59:36 -070039#include <linux/iommu-helper.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
Thierry Redingce5be5a2013-10-23 13:32:04 +020041#define CREATE_TRACE_POINTS
Zoltan Kiss2b2b6142013-09-04 21:11:05 +010042#include <trace/events/swiotlb.h>
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044#define OFFSET(val,align) ((unsigned long) \
45 ( (val) & ( (align) - 1)))
46
Alex Williamson0b9afed2005-09-06 11:20:49 -060047#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
48
49/*
50 * Minimum IO TLB size to bother booting with. Systems with mainly
51 * 64bit capable cards will only lightly use the swiotlb. If we can't
52 * allocate a contiguous 1MB, we're probably in trouble anyway.
53 */
54#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
55
Geert Uytterhoeven1fd1e6c2016-12-16 14:28:41 +010056enum swiotlb_force swiotlb_force;
Linus Torvalds1da177e2005-04-16 15:20:36 -070057
58/*
Konrad Rzeszutek Wilkbfc55012010-05-10 15:54:20 -040059 * Used to do a quick range check in swiotlb_tbl_unmap_single and
60 * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 * API.
62 */
Alexander Duyckff7204a2012-10-15 10:19:28 -070063static phys_addr_t io_tlb_start, io_tlb_end;
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65/*
Uwe Kleine-Königb5950762010-11-01 15:38:34 -040066 * The number of IO TLB blocks (in groups of 64) between io_tlb_start and
Linus Torvalds1da177e2005-04-16 15:20:36 -070067 * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
68 */
69static unsigned long io_tlb_nslabs;
70
71/*
72 * When the IOMMU overflows we return a fallback buffer. This sets the size.
73 */
74static unsigned long io_tlb_overflow = 32*1024;
75
Alexander Duyckee3f6ba2012-10-15 10:19:34 -070076static phys_addr_t io_tlb_overflow_buffer;
Linus Torvalds1da177e2005-04-16 15:20:36 -070077
78/*
79 * This is a free list describing the number of free entries available from
80 * each index
81 */
82static unsigned int *io_tlb_list;
83static unsigned int io_tlb_index;
84
85/*
86 * We need to save away the original address corresponding to a mapped entry
87 * for the sync operations.
88 */
Jan Beulich8e0629c2014-06-02 14:58:25 +010089#define INVALID_PHYS_ADDR (~(phys_addr_t)0)
Becky Brucebc40ac62008-12-22 10:26:08 -080090static phys_addr_t *io_tlb_orig_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070091
92/*
93 * Protect the above data structures in the map and unmap calls
94 */
95static DEFINE_SPINLOCK(io_tlb_lock);
96
FUJITA Tomonori5740afd2009-11-10 19:46:18 +090097static int late_alloc;
98
Linus Torvalds1da177e2005-04-16 15:20:36 -070099static int __init
100setup_io_tlb_npages(char *str)
101{
102 if (isdigit(*str)) {
Alex Williamsone8579e72005-08-04 13:06:00 -0700103 io_tlb_nslabs = simple_strtoul(str, &str, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104 /* avoid tail segment of size < IO_TLB_SEGSIZE */
105 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
106 }
107 if (*str == ',')
108 ++str;
Geert Uytterhoeven41c6b3e2016-12-16 14:28:42 +0100109 if (!strcmp(str, "force")) {
Geert Uytterhoeven1fd1e6c2016-12-16 14:28:41 +0100110 swiotlb_force = SWIOTLB_FORCE;
Geert Uytterhoeven41c6b3e2016-12-16 14:28:42 +0100111 } else if (!strcmp(str, "noforce")) {
112 swiotlb_force = SWIOTLB_NO_FORCE;
113 io_tlb_nslabs = 1;
114 }
FUJITA Tomonorib18485e2009-11-12 00:03:28 +0900115
Yinghai Luc729de82013-04-15 22:23:45 -0700116 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117}
Yinghai Luc729de82013-04-15 22:23:45 -0700118early_param("swiotlb", setup_io_tlb_npages);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119/* make io_tlb_overflow tunable too? */
120
Konrad Rzeszutek Wilkf21ffe92011-08-11 16:50:56 -0400121unsigned long swiotlb_nr_tbl(void)
FUJITA Tomonori5f98ecd2011-06-05 11:47:29 +0900122{
123 return io_tlb_nslabs;
124}
Konrad Rzeszutek Wilkf21ffe92011-08-11 16:50:56 -0400125EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);
Yinghai Luc729de82013-04-15 22:23:45 -0700126
127/* default to 64MB */
128#define IO_TLB_DEFAULT_SIZE (64UL<<20)
129unsigned long swiotlb_size_or_default(void)
130{
131 unsigned long size;
132
133 size = io_tlb_nslabs << IO_TLB_SHIFT;
134
135 return size ? size : (IO_TLB_DEFAULT_SIZE);
136}
137
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900138/* Note that this doesn't work with highmem page */
Jeremy Fitzhardinge70a7d3c2008-12-22 10:26:05 -0800139static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
140 volatile void *address)
Ian Campbelle08e1f72008-12-16 12:17:30 -0800141{
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900142 return phys_to_dma(hwdev, virt_to_phys(address));
Ian Campbelle08e1f72008-12-16 12:17:30 -0800143}
144
Yinghai Luac2cbab2013-01-24 12:20:16 -0800145static bool no_iotlb_memory;
146
FUJITA Tomonoriad32e8c2009-11-10 19:46:19 +0900147void swiotlb_print_info(void)
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800148{
FUJITA Tomonoriad32e8c2009-11-10 19:46:19 +0900149 unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700150 unsigned char *vstart, *vend;
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800151
Yinghai Luac2cbab2013-01-24 12:20:16 -0800152 if (no_iotlb_memory) {
153 pr_warn("software IO TLB: No low mem\n");
154 return;
155 }
156
Alexander Duyckff7204a2012-10-15 10:19:28 -0700157 vstart = phys_to_virt(io_tlb_start);
Alexander Duyckc40dba02012-10-15 10:19:22 -0700158 vend = phys_to_virt(io_tlb_end);
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800159
Bjorn Helgaas3af684c2012-05-29 15:06:29 -0700160 printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n",
Alexander Duyckff7204a2012-10-15 10:19:28 -0700161 (unsigned long long)io_tlb_start,
Alexander Duyckc40dba02012-10-15 10:19:22 -0700162 (unsigned long long)io_tlb_end,
Alexander Duyckff7204a2012-10-15 10:19:28 -0700163 bytes >> 20, vstart, vend - 1);
Ian Campbell2e5b2b82008-12-16 12:17:34 -0800164}
165
Yinghai Luac2cbab2013-01-24 12:20:16 -0800166int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167{
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700168 void *v_overflow_buffer;
Jan Beulich563aaf02007-02-05 18:51:25 -0800169 unsigned long i, bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400171 bytes = nslabs << IO_TLB_SHIFT;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400173 io_tlb_nslabs = nslabs;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700174 io_tlb_start = __pa(tlb);
175 io_tlb_end = io_tlb_start + bytes;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176
177 /*
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700178 * Get the overflow emergency buffer
179 */
Yinghai Luad6492b2014-01-27 17:06:49 -0800180 v_overflow_buffer = memblock_virt_alloc_low_nopanic(
Santosh Shilimkar457ff1d2014-01-21 15:50:30 -0800181 PAGE_ALIGN(io_tlb_overflow),
182 PAGE_SIZE);
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700183 if (!v_overflow_buffer)
Yinghai Luac2cbab2013-01-24 12:20:16 -0800184 return -ENOMEM;
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700185
186 io_tlb_overflow_buffer = __pa(v_overflow_buffer);
187
188 /*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700189 * Allocate and initialize the free list array. This array is used
190 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
191 * between io_tlb_start and io_tlb_end.
192 */
Santosh Shilimkar457ff1d2014-01-21 15:50:30 -0800193 io_tlb_list = memblock_virt_alloc(
194 PAGE_ALIGN(io_tlb_nslabs * sizeof(int)),
195 PAGE_SIZE);
Santosh Shilimkar457ff1d2014-01-21 15:50:30 -0800196 io_tlb_orig_addr = memblock_virt_alloc(
197 PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)),
198 PAGE_SIZE);
Jan Beulich8e0629c2014-06-02 14:58:25 +0100199 for (i = 0; i < io_tlb_nslabs; i++) {
200 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
201 io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
202 }
203 io_tlb_index = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
FUJITA Tomonoriad32e8c2009-11-10 19:46:19 +0900205 if (verbose)
206 swiotlb_print_info();
Yinghai Luac2cbab2013-01-24 12:20:16 -0800207
208 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209}
210
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400211/*
212 * Statically reserve bounce buffer space and initialize bounce buffer data
213 * structures for the software IO TLB used to implement the DMA API.
214 */
Yinghai Luac2cbab2013-01-24 12:20:16 -0800215void __init
216swiotlb_init(int verbose)
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400217{
Yinghai Luc729de82013-04-15 22:23:45 -0700218 size_t default_size = IO_TLB_DEFAULT_SIZE;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700219 unsigned char *vstart;
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400220 unsigned long bytes;
221
222 if (!io_tlb_nslabs) {
223 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
224 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
225 }
226
227 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
228
Yinghai Luac2cbab2013-01-24 12:20:16 -0800229 /* Get IO TLB memory from the low pages */
Yinghai Luad6492b2014-01-27 17:06:49 -0800230 vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE);
Yinghai Luac2cbab2013-01-24 12:20:16 -0800231 if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
232 return;
FUJITA Tomonoriabbceff2010-05-10 15:15:12 -0400233
Yinghai Luac2cbab2013-01-24 12:20:16 -0800234 if (io_tlb_start)
Santosh Shilimkar457ff1d2014-01-21 15:50:30 -0800235 memblock_free_early(io_tlb_start,
236 PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
Yinghai Luac2cbab2013-01-24 12:20:16 -0800237 pr_warn("Cannot allocate SWIOTLB buffer");
238 no_iotlb_memory = true;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700239}
240
Alex Williamson0b9afed2005-09-06 11:20:49 -0600241/*
242 * Systems with larger DMA zones (those that don't support ISA) can
243 * initialize the swiotlb later using the slab allocator if needed.
244 * This should be just like above, but with some error catching.
245 */
246int
Jan Beulich563aaf02007-02-05 18:51:25 -0800247swiotlb_late_init_with_default_size(size_t default_size)
Alex Williamson0b9afed2005-09-06 11:20:49 -0600248{
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400249 unsigned long bytes, req_nslabs = io_tlb_nslabs;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700250 unsigned char *vstart = NULL;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600251 unsigned int order;
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400252 int rc = 0;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600253
254 if (!io_tlb_nslabs) {
255 io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
256 io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
257 }
258
259 /*
260 * Get IO TLB memory from the low pages
261 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800262 order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600263 io_tlb_nslabs = SLABS_PER_PAGE << order;
Jan Beulich563aaf02007-02-05 18:51:25 -0800264 bytes = io_tlb_nslabs << IO_TLB_SHIFT;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600265
266 while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
Alexander Duyckff7204a2012-10-15 10:19:28 -0700267 vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
268 order);
269 if (vstart)
Alex Williamson0b9afed2005-09-06 11:20:49 -0600270 break;
271 order--;
272 }
273
Alexander Duyckff7204a2012-10-15 10:19:28 -0700274 if (!vstart) {
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400275 io_tlb_nslabs = req_nslabs;
276 return -ENOMEM;
277 }
Jan Beulich563aaf02007-02-05 18:51:25 -0800278 if (order != get_order(bytes)) {
Alex Williamson0b9afed2005-09-06 11:20:49 -0600279 printk(KERN_WARNING "Warning: only able to allocate %ld MB "
280 "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
281 io_tlb_nslabs = SLABS_PER_PAGE << order;
282 }
Alexander Duyckff7204a2012-10-15 10:19:28 -0700283 rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400284 if (rc)
Alexander Duyckff7204a2012-10-15 10:19:28 -0700285 free_pages((unsigned long)vstart, order);
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400286 return rc;
287}
288
289int
290swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
291{
292 unsigned long i, bytes;
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700293 unsigned char *v_overflow_buffer;
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400294
295 bytes = nslabs << IO_TLB_SHIFT;
296
297 io_tlb_nslabs = nslabs;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700298 io_tlb_start = virt_to_phys(tlb);
299 io_tlb_end = io_tlb_start + bytes;
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400300
Alexander Duyckff7204a2012-10-15 10:19:28 -0700301 memset(tlb, 0, bytes);
Alex Williamson0b9afed2005-09-06 11:20:49 -0600302
303 /*
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700304 * Get the overflow emergency buffer
305 */
306 v_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
307 get_order(io_tlb_overflow));
308 if (!v_overflow_buffer)
309 goto cleanup2;
310
311 io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer);
312
313 /*
Alex Williamson0b9afed2005-09-06 11:20:49 -0600314 * Allocate and initialize the free list array. This array is used
315 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
316 * between io_tlb_start and io_tlb_end.
317 */
318 io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
319 get_order(io_tlb_nslabs * sizeof(int)));
320 if (!io_tlb_list)
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700321 goto cleanup3;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600322
Becky Brucebc40ac62008-12-22 10:26:08 -0800323 io_tlb_orig_addr = (phys_addr_t *)
324 __get_free_pages(GFP_KERNEL,
325 get_order(io_tlb_nslabs *
326 sizeof(phys_addr_t)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600327 if (!io_tlb_orig_addr)
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700328 goto cleanup4;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600329
Jan Beulich8e0629c2014-06-02 14:58:25 +0100330 for (i = 0; i < io_tlb_nslabs; i++) {
331 io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
332 io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
333 }
334 io_tlb_index = 0;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600335
FUJITA Tomonoriad32e8c2009-11-10 19:46:19 +0900336 swiotlb_print_info();
Alex Williamson0b9afed2005-09-06 11:20:49 -0600337
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900338 late_alloc = 1;
339
Alex Williamson0b9afed2005-09-06 11:20:49 -0600340 return 0;
341
342cleanup4:
Tony Luck25667d62007-03-06 13:31:45 -0800343 free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
344 sizeof(int)));
Alex Williamson0b9afed2005-09-06 11:20:49 -0600345 io_tlb_list = NULL;
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700346cleanup3:
347 free_pages((unsigned long)v_overflow_buffer,
348 get_order(io_tlb_overflow));
349 io_tlb_overflow_buffer = 0;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600350cleanup2:
Alexander Duyckc40dba02012-10-15 10:19:22 -0700351 io_tlb_end = 0;
Alexander Duyckff7204a2012-10-15 10:19:28 -0700352 io_tlb_start = 0;
Konrad Rzeszutek Wilk74838b72012-07-27 20:55:27 -0400353 io_tlb_nslabs = 0;
Alex Williamson0b9afed2005-09-06 11:20:49 -0600354 return -ENOMEM;
355}
356
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900357void __init swiotlb_free(void)
358{
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700359 if (!io_tlb_orig_addr)
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900360 return;
361
362 if (late_alloc) {
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700363 free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer),
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900364 get_order(io_tlb_overflow));
365 free_pages((unsigned long)io_tlb_orig_addr,
366 get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
367 free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
368 sizeof(int)));
Alexander Duyckff7204a2012-10-15 10:19:28 -0700369 free_pages((unsigned long)phys_to_virt(io_tlb_start),
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900370 get_order(io_tlb_nslabs << IO_TLB_SHIFT));
371 } else {
Santosh Shilimkar457ff1d2014-01-21 15:50:30 -0800372 memblock_free_late(io_tlb_overflow_buffer,
373 PAGE_ALIGN(io_tlb_overflow));
374 memblock_free_late(__pa(io_tlb_orig_addr),
375 PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)));
376 memblock_free_late(__pa(io_tlb_list),
377 PAGE_ALIGN(io_tlb_nslabs * sizeof(int)));
378 memblock_free_late(io_tlb_start,
379 PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900380 }
Konrad Rzeszutek Wilkf21ffe92011-08-11 16:50:56 -0400381 io_tlb_nslabs = 0;
FUJITA Tomonori5740afd2009-11-10 19:46:18 +0900382}
383
Akinobu Mita9c5a3622014-06-04 16:06:50 -0700384int is_swiotlb_buffer(phys_addr_t paddr)
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900385{
Alexander Duyckff7204a2012-10-15 10:19:28 -0700386 return paddr >= io_tlb_start && paddr < io_tlb_end;
FUJITA Tomonori640aebf2008-09-08 18:53:50 +0900387}
388
Linus Torvalds1da177e2005-04-16 15:20:36 -0700389/*
Becky Brucefb05a372008-12-22 10:26:09 -0800390 * Bounce: copy the swiotlb buffer back to the original dma location
391 */
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700392static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr,
393 size_t size, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700394{
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700395 unsigned long pfn = PFN_DOWN(orig_addr);
396 unsigned char *vaddr = phys_to_virt(tlb_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Becky Brucefb05a372008-12-22 10:26:09 -0800398 if (PageHighMem(pfn_to_page(pfn))) {
399 /* The buffer does not have a mapping. Map it in and copy */
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700400 unsigned int offset = orig_addr & ~PAGE_MASK;
Becky Brucefb05a372008-12-22 10:26:09 -0800401 char *buffer;
402 unsigned int sz = 0;
403 unsigned long flags;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700404
Becky Brucefb05a372008-12-22 10:26:09 -0800405 while (size) {
Becky Bruce67131ad2009-04-08 09:09:16 -0500406 sz = min_t(size_t, PAGE_SIZE - offset, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
Becky Brucefb05a372008-12-22 10:26:09 -0800408 local_irq_save(flags);
Cong Wangc3eede82011-11-25 23:14:39 +0800409 buffer = kmap_atomic(pfn_to_page(pfn));
Becky Brucefb05a372008-12-22 10:26:09 -0800410 if (dir == DMA_TO_DEVICE)
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700411 memcpy(vaddr, buffer + offset, sz);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700412 else
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700413 memcpy(buffer + offset, vaddr, sz);
Cong Wangc3eede82011-11-25 23:14:39 +0800414 kunmap_atomic(buffer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700415 local_irq_restore(flags);
Becky Brucefb05a372008-12-22 10:26:09 -0800416
417 size -= sz;
418 pfn++;
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700419 vaddr += sz;
Becky Brucefb05a372008-12-22 10:26:09 -0800420 offset = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421 }
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700422 } else if (dir == DMA_TO_DEVICE) {
423 memcpy(vaddr, phys_to_virt(orig_addr), size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424 } else {
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700425 memcpy(phys_to_virt(orig_addr), vaddr, size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 }
427}
428
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700429phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
430 dma_addr_t tbl_dma_addr,
431 phys_addr_t orig_addr, size_t size,
432 enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700433{
434 unsigned long flags;
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700435 phys_addr_t tlb_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 unsigned int nslots, stride, index, wrap;
437 int i;
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800438 unsigned long mask;
439 unsigned long offset_slots;
440 unsigned long max_slots;
441
Yinghai Luac2cbab2013-01-24 12:20:16 -0800442 if (no_iotlb_memory)
443 panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");
444
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800445 mask = dma_get_seg_boundary(hwdev);
FUJITA Tomonori681cc5c2008-02-04 22:28:16 -0800446
FUJITA Tomonorieb605a52010-05-10 15:14:54 -0400447 tbl_dma_addr &= mask;
448
449 offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
Ian Campbella5ddde4a2008-12-16 12:17:29 -0800450
451 /*
452 * Carefully handle integer overflow which can occur when mask == ~0UL.
453 */
Jan Beulichb15a38912008-03-13 09:13:30 +0000454 max_slots = mask + 1
455 ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
456 : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457
458 /*
459 * For mappings greater than a page, we limit the stride (and
460 * hence alignment) to a page size.
461 */
462 nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
463 if (size > PAGE_SIZE)
464 stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
465 else
466 stride = 1;
467
Eric Sesterhenn34814542006-03-24 18:47:11 +0100468 BUG_ON(!nslots);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469
470 /*
471 * Find suitable number of IO TLB entries size that will fit this
472 * request and allocate a buffer from that IO TLB pool.
473 */
474 spin_lock_irqsave(&io_tlb_lock, flags);
Andrew Mortona7133a12008-04-29 00:59:36 -0700475 index = ALIGN(io_tlb_index, stride);
476 if (index >= io_tlb_nslabs)
477 index = 0;
478 wrap = index;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700479
Andrew Mortona7133a12008-04-29 00:59:36 -0700480 do {
FUJITA Tomonoria8522502008-04-29 00:59:36 -0700481 while (iommu_is_span_boundary(index, nslots, offset_slots,
482 max_slots)) {
Jan Beulichb15a38912008-03-13 09:13:30 +0000483 index += stride;
484 if (index >= io_tlb_nslabs)
485 index = 0;
Andrew Mortona7133a12008-04-29 00:59:36 -0700486 if (index == wrap)
487 goto not_found;
488 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489
Andrew Mortona7133a12008-04-29 00:59:36 -0700490 /*
491 * If we find a slot that indicates we have 'nslots' number of
492 * contiguous buffers, we allocate the buffers from that slot
493 * and mark the entries as '0' indicating unavailable.
494 */
495 if (io_tlb_list[index] >= nslots) {
496 int count = 0;
497
498 for (i = index; i < (int) (index + nslots); i++)
499 io_tlb_list[i] = 0;
500 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
501 io_tlb_list[i] = ++count;
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700502 tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT);
Andrew Mortona7133a12008-04-29 00:59:36 -0700503
504 /*
505 * Update the indices to avoid searching in the next
506 * round.
507 */
508 io_tlb_index = ((index + nslots) < io_tlb_nslabs
509 ? (index + nslots) : 0);
510
511 goto found;
512 }
513 index += stride;
514 if (index >= io_tlb_nslabs)
515 index = 0;
516 } while (index != wrap);
517
518not_found:
519 spin_unlock_irqrestore(&io_tlb_lock, flags);
Konrad Rzeszutek Wilk0cb637b2013-12-16 14:05:01 -0500520 if (printk_ratelimit())
521 dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700522 return SWIOTLB_MAP_ERROR;
Andrew Mortona7133a12008-04-29 00:59:36 -0700523found:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 spin_unlock_irqrestore(&io_tlb_lock, flags);
525
526 /*
527 * Save away the mapping from the original address to the DMA address.
528 * This is needed when we sync the memory. Then we sync the buffer if
529 * needed.
530 */
Becky Brucebc40ac62008-12-22 10:26:08 -0800531 for (i = 0; i < nslots; i++)
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700532 io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533 if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700534 swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700536 return tlb_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537}
Konrad Rzeszutek Wilkd7ef1532010-05-28 11:37:10 -0400538EXPORT_SYMBOL_GPL(swiotlb_tbl_map_single);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539
540/*
FUJITA Tomonorieb605a52010-05-10 15:14:54 -0400541 * Allocates bounce buffer and returns its kernel virtual address.
542 */
543
Alexandre Courbot023600f2015-05-26 18:02:54 +0900544static phys_addr_t
545map_single(struct device *hwdev, phys_addr_t phys, size_t size,
546 enum dma_data_direction dir)
FUJITA Tomonorieb605a52010-05-10 15:14:54 -0400547{
Geert Uytterhoeven41c6b3e2016-12-16 14:28:42 +0100548 dma_addr_t start_dma_addr;
FUJITA Tomonorieb605a52010-05-10 15:14:54 -0400549
Geert Uytterhoeven41c6b3e2016-12-16 14:28:42 +0100550 if (swiotlb_force == SWIOTLB_NO_FORCE) {
551 dev_warn_ratelimited(hwdev, "Cannot do DMA to address %pa\n",
552 &phys);
553 return SWIOTLB_MAP_ERROR;
554 }
555
556 start_dma_addr = phys_to_dma(hwdev, io_tlb_start);
FUJITA Tomonorieb605a52010-05-10 15:14:54 -0400557 return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, dir);
558}
559
560/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700561 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
562 */
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700563void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
564 size_t size, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700565{
566 unsigned long flags;
567 int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700568 int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
569 phys_addr_t orig_addr = io_tlb_orig_addr[index];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700570
571 /*
572 * First, sync the memory before unmapping the entry
573 */
Jan Beulich8e0629c2014-06-02 14:58:25 +0100574 if (orig_addr != INVALID_PHYS_ADDR &&
575 ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700576 swiotlb_bounce(orig_addr, tlb_addr, size, DMA_FROM_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577
578 /*
579 * Return the buffer to the free list by setting the corresponding
André Goddard Rosaaf901ca2009-11-14 13:09:05 -0200580 * entries to indicate the number of contiguous entries available.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700581 * While returning the entries to the free list, we merge the entries
582 * with slots below and above the pool being returned.
583 */
584 spin_lock_irqsave(&io_tlb_lock, flags);
585 {
586 count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
587 io_tlb_list[index + nslots] : 0);
588 /*
589 * Step 1: return the slots to the free list, merging the
590 * slots with superceeding slots
591 */
Jan Beulich8e0629c2014-06-02 14:58:25 +0100592 for (i = index + nslots - 1; i >= index; i--) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700593 io_tlb_list[i] = ++count;
Jan Beulich8e0629c2014-06-02 14:58:25 +0100594 io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
595 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700596 /*
597 * Step 2: merge the returned slots with the preceding slots,
598 * if available (non zero)
599 */
600 for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
601 io_tlb_list[i] = ++count;
602 }
603 spin_unlock_irqrestore(&io_tlb_lock, flags);
604}
Konrad Rzeszutek Wilkd7ef1532010-05-28 11:37:10 -0400605EXPORT_SYMBOL_GPL(swiotlb_tbl_unmap_single);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606
Alexander Duyckfbfda892012-10-15 10:19:49 -0700607void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
608 size_t size, enum dma_data_direction dir,
609 enum dma_sync_target target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610{
Alexander Duyckfbfda892012-10-15 10:19:49 -0700611 int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
612 phys_addr_t orig_addr = io_tlb_orig_addr[index];
Becky Brucebc40ac62008-12-22 10:26:08 -0800613
Jan Beulich8e0629c2014-06-02 14:58:25 +0100614 if (orig_addr == INVALID_PHYS_ADDR)
615 return;
Alexander Duyckfbfda892012-10-15 10:19:49 -0700616 orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1);
Keir Fraserdf336d12007-07-21 04:37:24 -0700617
John W. Linvillede69e0f2005-09-29 14:44:57 -0700618 switch (target) {
619 case SYNC_FOR_CPU:
620 if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700621 swiotlb_bounce(orig_addr, tlb_addr,
Alexander Duyckfbfda892012-10-15 10:19:49 -0700622 size, DMA_FROM_DEVICE);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100623 else
624 BUG_ON(dir != DMA_TO_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700625 break;
626 case SYNC_FOR_DEVICE:
627 if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
Alexander Duyckaf51a9f2012-10-15 10:19:55 -0700628 swiotlb_bounce(orig_addr, tlb_addr,
Alexander Duyckfbfda892012-10-15 10:19:49 -0700629 size, DMA_TO_DEVICE);
Eric Sesterhenn34814542006-03-24 18:47:11 +0100630 else
631 BUG_ON(dir != DMA_FROM_DEVICE);
John W. Linvillede69e0f2005-09-29 14:44:57 -0700632 break;
633 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700634 BUG();
John W. Linvillede69e0f2005-09-29 14:44:57 -0700635 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636}
Konrad Rzeszutek Wilkd7ef1532010-05-28 11:37:10 -0400637EXPORT_SYMBOL_GPL(swiotlb_tbl_sync_single);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700638
639void *
640swiotlb_alloc_coherent(struct device *hwdev, size_t size,
Al Viro06a54492005-10-21 03:21:03 -0400641 dma_addr_t *dma_handle, gfp_t flags)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642{
Jan Beulich563aaf02007-02-05 18:51:25 -0800643 dma_addr_t dev_addr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700644 void *ret;
645 int order = get_order(size);
Yang Hongyang284901a2009-04-06 19:01:15 -0700646 u64 dma_mask = DMA_BIT_MASK(32);
FUJITA Tomonori1e74f302008-11-17 16:24:34 +0900647
648 if (hwdev && hwdev->coherent_dma_mask)
649 dma_mask = hwdev->coherent_dma_mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700650
Tony Luck25667d62007-03-06 13:31:45 -0800651 ret = (void *)__get_free_pages(flags, order);
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700652 if (ret) {
653 dev_addr = swiotlb_virt_to_bus(hwdev, ret);
654 if (dev_addr + size - 1 > dma_mask) {
655 /*
656 * The allocated memory isn't reachable by the device.
657 */
658 free_pages((unsigned long) ret, order);
659 ret = NULL;
660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700661 }
662 if (!ret) {
663 /*
Konrad Rzeszutek Wilkbfc55012010-05-10 15:54:20 -0400664 * We are either out of memory or the device can't DMA to
665 * GFP_DMA memory; fall back on map_single(), which
Becky Bruceceb5ac32009-04-08 09:09:15 -0500666 * will grab memory from the lowest available address range.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 */
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700668 phys_addr_t paddr = map_single(hwdev, 0, size, DMA_FROM_DEVICE);
669 if (paddr == SWIOTLB_MAP_ERROR)
Joerg Roedel94cc81f2015-06-10 17:49:40 +0200670 goto err_warn;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700671
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700672 ret = phys_to_virt(paddr);
673 dev_addr = phys_to_dma(hwdev, paddr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700675 /* Confirm address can be DMA'd by device */
676 if (dev_addr + size - 1 > dma_mask) {
677 printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
678 (unsigned long long)dma_mask,
679 (unsigned long long)dev_addr);
FUJITA Tomonoria2b89b52008-10-23 18:42:03 +0900680
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700681 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
682 swiotlb_tbl_unmap_single(hwdev, paddr,
683 size, DMA_TO_DEVICE);
Joerg Roedel94cc81f2015-06-10 17:49:40 +0200684 goto err_warn;
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700685 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700686 }
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700687
Linus Torvalds1da177e2005-04-16 15:20:36 -0700688 *dma_handle = dev_addr;
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700689 memset(ret, 0, size);
690
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 return ret;
Joerg Roedel94cc81f2015-06-10 17:49:40 +0200692
693err_warn:
694 pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n",
695 dev_name(hwdev), size);
696 dump_stack();
697
698 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900700EXPORT_SYMBOL(swiotlb_alloc_coherent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701
702void
703swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900704 dma_addr_t dev_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705{
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900706 phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900707
David Brownellaa248862007-08-10 13:10:27 -0700708 WARN_ON(irqs_disabled());
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900709 if (!is_swiotlb_buffer(paddr))
710 free_pages((unsigned long)vaddr, get_order(size));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711 else
Konrad Rzeszutek Wilkbfc55012010-05-10 15:54:20 -0400712 /* DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single */
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700713 swiotlb_tbl_unmap_single(hwdev, paddr, size, DMA_TO_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700714}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900715EXPORT_SYMBOL(swiotlb_free_coherent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700716
717static void
Konrad Rzeszutek Wilk22d48262010-05-10 15:01:15 -0500718swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
719 int do_panic)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720{
Geert Uytterhoeven41c6b3e2016-12-16 14:28:42 +0100721 if (swiotlb_force == SWIOTLB_NO_FORCE)
722 return;
723
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 /*
725 * Ran out of IOMMU space for this operation. This is very bad.
726 * Unfortunately the drivers cannot handle this operation properly.
Tony Luck17e5ad62005-09-29 15:52:13 -0700727 * unless they check for dma_mapping_error (most don't)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700728 * When the mapping is small enough return a static buffer to limit
729 * the damage, or panic when the transfer is too big.
730 */
Jan Beulich563aaf02007-02-05 18:51:25 -0800731 printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
Kay Sievers94b32482009-01-06 10:44:37 -0800732 "device %s\n", size, dev ? dev_name(dev) : "?");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
Casey Dahlinc7084b32009-08-20 16:27:56 -0700734 if (size <= io_tlb_overflow || !do_panic)
735 return;
736
737 if (dir == DMA_BIDIRECTIONAL)
738 panic("DMA: Random memory could be DMA accessed\n");
739 if (dir == DMA_FROM_DEVICE)
740 panic("DMA: Random memory could be DMA written\n");
741 if (dir == DMA_TO_DEVICE)
742 panic("DMA: Random memory could be DMA read\n");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700743}
744
745/*
746 * Map a single buffer of the indicated size for DMA in streaming mode. The
Tony Luck17e5ad62005-09-29 15:52:13 -0700747 * physical address to use is returned.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 *
749 * Once the device is given the dma address, the device owns this memory until
Becky Bruceceb5ac32009-04-08 09:09:15 -0500750 * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751 */
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900752dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
753 unsigned long offset, size_t size,
754 enum dma_data_direction dir,
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700755 unsigned long attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756{
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700757 phys_addr_t map, phys = page_to_phys(page) + offset;
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900758 dma_addr_t dev_addr = phys_to_dma(dev, phys);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700759
Eric Sesterhenn34814542006-03-24 18:47:11 +0100760 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700761 /*
Becky Bruceceb5ac32009-04-08 09:09:15 -0500762 * If the address happens to be in the device's DMA window,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 * we can safely return the device addr and not worry about bounce
764 * buffering it.
765 */
Geert Uytterhoeven1fd1e6c2016-12-16 14:28:41 +0100766 if (dma_capable(dev, dev_addr, size) && swiotlb_force != SWIOTLB_FORCE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 return dev_addr;
768
Zoltan Kiss2b2b6142013-09-04 21:11:05 +0100769 trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);
770
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700771 /* Oh well, have to allocate and map a bounce buffer. */
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900772 map = map_single(dev, phys, size, dir);
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700773 if (map == SWIOTLB_MAP_ERROR) {
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900774 swiotlb_full(dev, size, dir, 1);
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700775 return phys_to_dma(dev, io_tlb_overflow_buffer);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776 }
777
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700778 dev_addr = phys_to_dma(dev, map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700780 /* Ensure that the address returned is DMA'ble */
FUJITA Tomonorifba99fa2011-02-25 14:44:16 -0800781 if (!dma_capable(dev, dev_addr, size)) {
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700782 swiotlb_tbl_unmap_single(dev, map, size, dir);
Alexander Duyckee3f6ba2012-10-15 10:19:34 -0700783 return phys_to_dma(dev, io_tlb_overflow_buffer);
FUJITA Tomonorifba99fa2011-02-25 14:44:16 -0800784 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785
786 return dev_addr;
787}
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900788EXPORT_SYMBOL_GPL(swiotlb_map_page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700789
790/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 * Unmap a single streaming mode DMA translation. The dma_addr and size must
Becky Bruceceb5ac32009-04-08 09:09:15 -0500792 * match what was provided for in a previous swiotlb_map_page call. All
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 * other usages are undefined.
794 *
795 * After this call, reads by the cpu to the buffer are guaranteed to see
796 * whatever the device wrote there.
797 */
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500798static void unmap_single(struct device *hwdev, dma_addr_t dev_addr,
Konrad Rzeszutek Wilk22d48262010-05-10 15:01:15 -0500799 size_t size, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800{
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900801 phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802
Eric Sesterhenn34814542006-03-24 18:47:11 +0100803 BUG_ON(dir == DMA_NONE);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500804
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900805 if (is_swiotlb_buffer(paddr)) {
Alexander Duyck61ca08c2012-10-15 10:19:44 -0700806 swiotlb_tbl_unmap_single(hwdev, paddr, size, dir);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500807 return;
808 }
809
810 if (dir != DMA_FROM_DEVICE)
811 return;
812
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900813 /*
814 * phys_to_virt doesn't work with hihgmem page but we could
815 * call dma_mark_clean() with hihgmem page here. However, we
816 * are fine since dma_mark_clean() is null on POWERPC. We can
817 * make dma_mark_clean() take a physical address if necessary.
818 */
819 dma_mark_clean(phys_to_virt(paddr), size);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500820}
821
822void swiotlb_unmap_page(struct device *hwdev, dma_addr_t dev_addr,
823 size_t size, enum dma_data_direction dir,
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700824 unsigned long attrs)
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500825{
826 unmap_single(hwdev, dev_addr, size, dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827}
FUJITA Tomonorif98eee82009-01-05 23:59:03 +0900828EXPORT_SYMBOL_GPL(swiotlb_unmap_page);
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900829
Linus Torvalds1da177e2005-04-16 15:20:36 -0700830/*
831 * Make physical memory consistent for a single streaming mode DMA translation
832 * after a transfer.
833 *
Becky Bruceceb5ac32009-04-08 09:09:15 -0500834 * If you perform a swiotlb_map_page() but wish to interrogate the buffer
Tony Luck17e5ad62005-09-29 15:52:13 -0700835 * using the cpu, yet do not wish to teardown the dma mapping, you must
836 * call this function before doing so. At the next point you give the dma
Linus Torvalds1da177e2005-04-16 15:20:36 -0700837 * address back to the card, you must first perform a
838 * swiotlb_dma_sync_for_device, and then the device again owns the buffer
839 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800840static void
John W. Linville8270f3f2005-09-29 14:43:32 -0700841swiotlb_sync_single(struct device *hwdev, dma_addr_t dev_addr,
Konrad Rzeszutek Wilkd7ef1532010-05-28 11:37:10 -0400842 size_t size, enum dma_data_direction dir,
843 enum dma_sync_target target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844{
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900845 phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846
Eric Sesterhenn34814542006-03-24 18:47:11 +0100847 BUG_ON(dir == DMA_NONE);
Becky Bruce380d6872009-04-08 09:09:20 -0500848
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900849 if (is_swiotlb_buffer(paddr)) {
Alexander Duyckfbfda892012-10-15 10:19:49 -0700850 swiotlb_tbl_sync_single(hwdev, paddr, size, dir, target);
Becky Bruce380d6872009-04-08 09:09:20 -0500851 return;
852 }
853
854 if (dir != DMA_FROM_DEVICE)
855 return;
856
FUJITA Tomonori02ca6462009-07-23 11:18:49 +0900857 dma_mark_clean(phys_to_virt(paddr), size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700858}
859
860void
John W. Linville8270f3f2005-09-29 14:43:32 -0700861swiotlb_sync_single_for_cpu(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900862 size_t size, enum dma_data_direction dir)
John W. Linville8270f3f2005-09-29 14:43:32 -0700863{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700864 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700865}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900866EXPORT_SYMBOL(swiotlb_sync_single_for_cpu);
John W. Linville8270f3f2005-09-29 14:43:32 -0700867
868void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700869swiotlb_sync_single_for_device(struct device *hwdev, dma_addr_t dev_addr,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900870 size_t size, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700872 swiotlb_sync_single(hwdev, dev_addr, size, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900874EXPORT_SYMBOL(swiotlb_sync_single_for_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875
876/*
877 * Map a set of buffers described by scatterlist in streaming mode for DMA.
Becky Bruceceb5ac32009-04-08 09:09:15 -0500878 * This is the scatter-gather version of the above swiotlb_map_page
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 * interface. Here the scatter gather list elements are each tagged with the
880 * appropriate dma address and length. They are obtained via
881 * sg_dma_{address,length}(SG).
882 *
883 * NOTE: An implementation may be able to use a smaller number of
884 * DMA address/length pairs than there are SG table elements.
885 * (for example via virtual mapping capabilities)
886 * The routine returns the number of addr/length pairs actually
887 * used, at most nents.
888 *
Becky Bruceceb5ac32009-04-08 09:09:15 -0500889 * Device ownership issues as mentioned above for swiotlb_map_page are the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700890 * same here.
891 */
892int
Arthur Kepner309df0c2008-04-29 01:00:32 -0700893swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700894 enum dma_data_direction dir, unsigned long attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200896 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700897 int i;
898
Eric Sesterhenn34814542006-03-24 18:47:11 +0100899 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700900
Jens Axboedbfd49f2007-05-11 14:56:18 +0200901 for_each_sg(sgl, sg, nelems, i) {
Ian Campbell961d7d02009-01-09 18:32:10 +0000902 phys_addr_t paddr = sg_phys(sg);
FUJITA Tomonori862d1962009-07-10 10:05:02 +0900903 dma_addr_t dev_addr = phys_to_dma(hwdev, paddr);
Becky Brucebc40ac62008-12-22 10:26:08 -0800904
Geert Uytterhoeven1fd1e6c2016-12-16 14:28:41 +0100905 if (swiotlb_force == SWIOTLB_FORCE ||
FUJITA Tomonorib9394642009-07-10 10:04:58 +0900906 !dma_capable(hwdev, dev_addr, sg->length)) {
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700907 phys_addr_t map = map_single(hwdev, sg_phys(sg),
908 sg->length, dir);
909 if (map == SWIOTLB_MAP_ERROR) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700910 /* Don't panic here, we expect map_sg users
911 to do proper error handling. */
912 swiotlb_full(hwdev, sg->length, dir, 0);
Arthur Kepner309df0c2008-04-29 01:00:32 -0700913 swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
914 attrs);
EunBong Song4d86ec72013-08-05 17:30:47 +0100915 sg_dma_len(sgl) = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916 return 0;
917 }
Alexander Duycke05ed4d2012-10-15 10:19:39 -0700918 sg->dma_address = phys_to_dma(hwdev, map);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700919 } else
920 sg->dma_address = dev_addr;
EunBong Song4d86ec72013-08-05 17:30:47 +0100921 sg_dma_len(sg) = sg->length;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922 }
923 return nelems;
924}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700925EXPORT_SYMBOL(swiotlb_map_sg_attrs);
926
927int
928swiotlb_map_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
Konrad Rzeszutek Wilk22d48262010-05-10 15:01:15 -0500929 enum dma_data_direction dir)
Arthur Kepner309df0c2008-04-29 01:00:32 -0700930{
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700931 return swiotlb_map_sg_attrs(hwdev, sgl, nelems, dir, 0);
Arthur Kepner309df0c2008-04-29 01:00:32 -0700932}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900933EXPORT_SYMBOL(swiotlb_map_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934
935/*
936 * Unmap a set of streaming mode DMA translations. Again, cpu read rules
Becky Bruceceb5ac32009-04-08 09:09:15 -0500937 * concerning calls here are the same as for swiotlb_unmap_page() above.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 */
939void
Arthur Kepner309df0c2008-04-29 01:00:32 -0700940swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700941 int nelems, enum dma_data_direction dir,
942 unsigned long attrs)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200944 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 int i;
946
Eric Sesterhenn34814542006-03-24 18:47:11 +0100947 BUG_ON(dir == DMA_NONE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500949 for_each_sg(sgl, sg, nelems, i)
EunBong Song4d86ec72013-08-05 17:30:47 +0100950 unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir);
Becky Bruce7fcebbd2009-04-08 09:09:19 -0500951
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952}
Arthur Kepner309df0c2008-04-29 01:00:32 -0700953EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
954
955void
956swiotlb_unmap_sg(struct device *hwdev, struct scatterlist *sgl, int nelems,
Konrad Rzeszutek Wilk22d48262010-05-10 15:01:15 -0500957 enum dma_data_direction dir)
Arthur Kepner309df0c2008-04-29 01:00:32 -0700958{
Krzysztof Kozlowski00085f12016-08-03 13:46:00 -0700959 return swiotlb_unmap_sg_attrs(hwdev, sgl, nelems, dir, 0);
Arthur Kepner309df0c2008-04-29 01:00:32 -0700960}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900961EXPORT_SYMBOL(swiotlb_unmap_sg);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700962
963/*
964 * Make physical memory consistent for a set of streaming mode DMA translations
965 * after a transfer.
966 *
967 * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
968 * and usage.
969 */
Andrew Mortonbe6b0262007-02-12 00:52:17 -0800970static void
Jens Axboedbfd49f2007-05-11 14:56:18 +0200971swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
Konrad Rzeszutek Wilkd7ef1532010-05-28 11:37:10 -0400972 int nelems, enum dma_data_direction dir,
973 enum dma_sync_target target)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974{
Jens Axboedbfd49f2007-05-11 14:56:18 +0200975 struct scatterlist *sg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 int i;
977
Becky Bruce380d6872009-04-08 09:09:20 -0500978 for_each_sg(sgl, sg, nelems, i)
979 swiotlb_sync_single(hwdev, sg->dma_address,
EunBong Song4d86ec72013-08-05 17:30:47 +0100980 sg_dma_len(sg), dir, target);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981}
982
983void
John W. Linville8270f3f2005-09-29 14:43:32 -0700984swiotlb_sync_sg_for_cpu(struct device *hwdev, struct scatterlist *sg,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900985 int nelems, enum dma_data_direction dir)
John W. Linville8270f3f2005-09-29 14:43:32 -0700986{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700987 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_CPU);
John W. Linville8270f3f2005-09-29 14:43:32 -0700988}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900989EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu);
John W. Linville8270f3f2005-09-29 14:43:32 -0700990
991void
Linus Torvalds1da177e2005-04-16 15:20:36 -0700992swiotlb_sync_sg_for_device(struct device *hwdev, struct scatterlist *sg,
FUJITA Tomonori160c1d82009-01-05 23:59:02 +0900993 int nelems, enum dma_data_direction dir)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994{
John W. Linvillede69e0f2005-09-29 14:44:57 -0700995 swiotlb_sync_sg(hwdev, sg, nelems, dir, SYNC_FOR_DEVICE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +0900997EXPORT_SYMBOL(swiotlb_sync_sg_for_device);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700998
999int
FUJITA Tomonori8d8bb392008-07-25 19:44:49 -07001000swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001001{
Alexander Duyckee3f6ba2012-10-15 10:19:34 -07001002 return (dma_addr == phys_to_dma(hwdev, io_tlb_overflow_buffer));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001003}
FUJITA Tomonori874d6a92008-12-28 15:02:07 +09001004EXPORT_SYMBOL(swiotlb_dma_mapping_error);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001005
1006/*
Tony Luck17e5ad62005-09-29 15:52:13 -07001007 * Return whether the given device DMA address mask can be supported
Linus Torvalds1da177e2005-04-16 15:20:36 -07001008 * properly. For example, if your device can only drive the low 24-bits
Tony Luck17e5ad62005-09-29 15:52:13 -07001009 * during bus mastering, then you would pass 0x00ffffff as the mask to
Linus Torvalds1da177e2005-04-16 15:20:36 -07001010 * this function.
1011 */
1012int
Jan Beulich563aaf02007-02-05 18:51:25 -08001013swiotlb_dma_supported(struct device *hwdev, u64 mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001014{
Alexander Duyckc40dba02012-10-15 10:19:22 -07001015 return phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001016}
Linus Torvalds1da177e2005-04-16 15:20:36 -07001017EXPORT_SYMBOL(swiotlb_dma_supported);