hc
2024-12-19 9370bb92b2d16684ee45cf24e879c93c509162da
kernel/kernel/dma/direct.c
....@@ -1,151 +1,395 @@
11 // SPDX-License-Identifier: GPL-2.0
22 /*
3
- * DMA operations that map physical memory directly without using an IOMMU or
4
- * flushing caches.
3
+ * Copyright (C) 2018-2020 Christoph Hellwig.
4
+ *
5
+ * DMA operations that map physical memory directly without using an IOMMU.
56 */
7
+#include <linux/memblock.h> /* for max_pfn */
68 #include <linux/export.h>
79 #include <linux/mm.h>
8
-#include <linux/dma-direct.h>
10
+#include <linux/dma-map-ops.h>
911 #include <linux/scatterlist.h>
10
-#include <linux/dma-contiguous.h>
1112 #include <linux/pfn.h>
13
+#include <linux/vmalloc.h>
1214 #include <linux/set_memory.h>
13
-
14
-#define DIRECT_MAPPING_ERROR 0
15
+#include <linux/slab.h>
16
+#include "direct.h"
1517
1618 /*
17
- * Most architectures use ZONE_DMA for the first 16 Megabytes, but
18
- * some use it for entirely different regions:
19
+ * Most architectures use ZONE_DMA for the first 16 Megabytes, but some use
20
+ * it for entirely different regions. In that case the arch code needs to
21
+ * override the variable below for dma-direct to work properly.
1922 */
20
-#ifndef ARCH_ZONE_DMA_BITS
21
-#define ARCH_ZONE_DMA_BITS 24
22
-#endif
23
+unsigned int zone_dma_bits __ro_after_init = 24;
2324
24
-/*
25
- * For AMD SEV all DMA must be to unencrypted addresses.
26
- */
27
-static inline bool force_dma_unencrypted(void)
25
+static inline dma_addr_t phys_to_dma_direct(struct device *dev,
26
+ phys_addr_t phys)
2827 {
29
- return sev_active();
28
+ if (force_dma_unencrypted(dev))
29
+ return phys_to_dma_unencrypted(dev, phys);
30
+ return phys_to_dma(dev, phys);
3031 }
3132
32
-static bool
33
-check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
34
- const char *caller)
33
+static inline struct page *dma_direct_to_page(struct device *dev,
34
+ dma_addr_t dma_addr)
3535 {
36
- if (unlikely(dev && !dma_capable(dev, dma_addr, size))) {
37
- if (!dev->dma_mask) {
38
- dev_err(dev,
39
- "%s: call on device without dma_mask\n",
40
- caller);
41
- return false;
42
- }
36
+ return pfn_to_page(PHYS_PFN(dma_to_phys(dev, dma_addr)));
37
+}
4338
44
- if (*dev->dma_mask >= DMA_BIT_MASK(32)) {
45
- dev_err(dev,
46
- "%s: overflow %pad+%zu of device mask %llx\n",
47
- caller, &dma_addr, size, *dev->dma_mask);
48
- }
49
- return false;
50
- }
51
- return true;
39
+u64 dma_direct_get_required_mask(struct device *dev)
40
+{
41
+ phys_addr_t phys = (phys_addr_t)(max_pfn - 1) << PAGE_SHIFT;
42
+ u64 max_dma = phys_to_dma_direct(dev, phys);
43
+
44
+ return (1ULL << (fls64(max_dma) - 1)) * 2 - 1;
45
+}
46
+
47
+static gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
48
+ u64 *phys_limit)
49
+{
50
+ u64 dma_limit = min_not_zero(dma_mask, dev->bus_dma_limit);
51
+
52
+ /*
53
+ * Optimistically try the zone that the physical address mask falls
54
+ * into first. If that returns memory that isn't actually addressable
55
+ * we will fallback to the next lower zone and try again.
56
+ *
57
+ * Note that GFP_DMA32 and GFP_DMA are no ops without the corresponding
58
+ * zones.
59
+ */
60
+ *phys_limit = dma_to_phys(dev, dma_limit);
61
+ if (*phys_limit <= DMA_BIT_MASK(zone_dma_bits))
62
+ return GFP_DMA;
63
+ if (*phys_limit <= DMA_BIT_MASK(32) &&
64
+ !zone_dma32_are_empty())
65
+ return GFP_DMA32;
66
+ return 0;
5267 }
5368
5469 static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
5570 {
56
- dma_addr_t addr = force_dma_unencrypted() ?
57
- __phys_to_dma(dev, phys) : phys_to_dma(dev, phys);
58
- return addr + size - 1 <= dev->coherent_dma_mask;
71
+ dma_addr_t dma_addr = phys_to_dma_direct(dev, phys);
72
+
73
+ if (dma_addr == DMA_MAPPING_ERROR)
74
+ return false;
75
+ return dma_addr + size - 1 <=
76
+ min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
5977 }
6078
61
-void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
62
- gfp_t gfp, unsigned long attrs)
79
+static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
80
+ gfp_t gfp)
6381 {
64
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
65
- int page_order = get_order(size);
82
+ int node = dev_to_node(dev);
6683 struct page *page = NULL;
67
- void *ret;
84
+ u64 phys_limit;
6885
69
- /* we always manually zero the memory once we are done: */
70
- gfp &= ~__GFP_ZERO;
86
+ WARN_ON_ONCE(!PAGE_ALIGNED(size));
7187
72
- /* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
73
- if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
74
- gfp |= GFP_DMA;
75
- if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
76
- gfp |= GFP_DMA32;
77
-
78
-again:
79
- /* CMA can be used only in the context which permits sleeping */
80
- if (gfpflags_allow_blocking(gfp)) {
81
- page = dma_alloc_from_contiguous(dev, count, page_order,
82
- gfp & __GFP_NOWARN);
83
- if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
84
- dma_release_from_contiguous(dev, page, count);
85
- page = NULL;
86
- }
87
- }
88
- if (!page)
89
- page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
90
-
88
+ gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
89
+ &phys_limit);
90
+ page = dma_alloc_contiguous(dev, size, gfp);
9191 if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
92
- __free_pages(page, page_order);
92
+ dma_free_contiguous(dev, page, size);
93
+ page = NULL;
94
+ }
95
+again:
96
+ if (!page)
97
+ page = alloc_pages_node(node, gfp, get_order(size));
98
+ if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
99
+ dma_free_contiguous(dev, page, size);
93100 page = NULL;
94101
95102 if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
96
- dev->coherent_dma_mask < DMA_BIT_MASK(64) &&
97
- !(gfp & (GFP_DMA32 | GFP_DMA))) {
103
+ phys_limit < DMA_BIT_MASK(64) &&
104
+ !(gfp & (GFP_DMA32 | GFP_DMA)) &&
105
+ !zone_dma32_are_empty()) {
98106 gfp |= GFP_DMA32;
99107 goto again;
100108 }
101109
102
- if (IS_ENABLED(CONFIG_ZONE_DMA) &&
103
- dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
104
- !(gfp & GFP_DMA)) {
110
+ if (IS_ENABLED(CONFIG_ZONE_DMA) && !(gfp & GFP_DMA)) {
105111 gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
106112 goto again;
107113 }
108114 }
109115
116
+ return page;
117
+}
118
+
119
+static void *dma_direct_alloc_from_pool(struct device *dev, size_t size,
120
+ dma_addr_t *dma_handle, gfp_t gfp)
121
+{
122
+ struct page *page;
123
+ u64 phys_mask;
124
+ void *ret;
125
+
126
+ gfp |= dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
127
+ &phys_mask);
128
+ page = dma_alloc_from_pool(dev, size, &ret, gfp, dma_coherent_ok);
110129 if (!page)
111130 return NULL;
112
- ret = page_address(page);
113
- if (force_dma_unencrypted()) {
114
- set_memory_decrypted((unsigned long)ret, 1 << page_order);
115
- *dma_handle = __phys_to_dma(dev, page_to_phys(page));
116
- } else {
117
- *dma_handle = phys_to_dma(dev, page_to_phys(page));
118
- }
119
- memset(ret, 0, size);
131
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
120132 return ret;
121133 }
122134
123
-/*
124
- * NOTE: this function must never look at the dma_addr argument, because we want
125
- * to be able to use it as a helper for iommu implementations as well.
126
- */
127
-void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
128
- dma_addr_t dma_addr, unsigned long attrs)
135
+void *dma_direct_alloc(struct device *dev, size_t size,
136
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
129137 {
130
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
131
- unsigned int page_order = get_order(size);
138
+ struct page *page;
139
+ void *ret;
140
+ int err;
132141
133
- if (force_dma_unencrypted())
134
- set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
135
- if (!dma_release_from_contiguous(dev, virt_to_page(cpu_addr), count))
136
- free_pages((unsigned long)cpu_addr, page_order);
142
+ size = PAGE_ALIGN(size);
143
+ if (attrs & DMA_ATTR_NO_WARN)
144
+ gfp |= __GFP_NOWARN;
145
+
146
+ if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
147
+ !force_dma_unencrypted(dev)) {
148
+ page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
149
+ if (!page)
150
+ return NULL;
151
+ /* remove any dirty cache lines on the kernel alias */
152
+ if (!PageHighMem(page))
153
+ arch_dma_prep_coherent(page, size);
154
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
155
+ /* return the page pointer as the opaque cookie */
156
+ return page;
157
+ }
158
+
159
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
160
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
161
+ !dev_is_dma_coherent(dev))
162
+ return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
163
+
164
+ /*
165
+ * Remapping or decrypting memory may block. If either is required and
166
+ * we can't block, allocate the memory from the atomic pools.
167
+ */
168
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
169
+ !gfpflags_allow_blocking(gfp) &&
170
+ (force_dma_unencrypted(dev) ||
171
+ (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
172
+ return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
173
+
174
+ /* we always manually zero the memory once we are done */
175
+ page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
176
+ if (!page)
177
+ return NULL;
178
+
179
+ if ((IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
180
+ !dev_is_dma_coherent(dev)) ||
181
+ (IS_ENABLED(CONFIG_DMA_REMAP) && PageHighMem(page))) {
182
+ /* remove any dirty cache lines on the kernel alias */
183
+ arch_dma_prep_coherent(page, size);
184
+
185
+ /* create a coherent mapping */
186
+ ret = dma_common_contiguous_remap(page, size,
187
+ dma_pgprot(dev, PAGE_KERNEL, attrs),
188
+ __builtin_return_address(0));
189
+ if (!ret)
190
+ goto out_free_pages;
191
+ if (force_dma_unencrypted(dev)) {
192
+ err = set_memory_decrypted((unsigned long)ret,
193
+ PFN_UP(size));
194
+ if (err)
195
+ goto out_free_pages;
196
+ }
197
+ memset(ret, 0, size);
198
+ goto done;
199
+ }
200
+
201
+ if (PageHighMem(page)) {
202
+ /*
203
+ * Depending on the cma= arguments and per-arch setup
204
+ * dma_alloc_contiguous could return highmem pages.
205
+ * Without remapping there is no way to return them here,
206
+ * so log an error and fail.
207
+ */
208
+ dev_info(dev, "Rejecting highmem page from CMA.\n");
209
+ goto out_free_pages;
210
+ }
211
+
212
+ ret = page_address(page);
213
+ if (force_dma_unencrypted(dev)) {
214
+ err = set_memory_decrypted((unsigned long)ret,
215
+ PFN_UP(size));
216
+ if (err)
217
+ goto out_free_pages;
218
+ }
219
+
220
+ memset(ret, 0, size);
221
+
222
+ if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
223
+ !dev_is_dma_coherent(dev)) {
224
+ arch_dma_prep_coherent(page, size);
225
+ ret = arch_dma_set_uncached(ret, size);
226
+ if (IS_ERR(ret))
227
+ goto out_encrypt_pages;
228
+ }
229
+done:
230
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
231
+ return ret;
232
+
233
+out_encrypt_pages:
234
+ if (force_dma_unencrypted(dev)) {
235
+ err = set_memory_encrypted((unsigned long)page_address(page),
236
+ PFN_UP(size));
237
+ /* If memory cannot be re-encrypted, it must be leaked */
238
+ if (err)
239
+ return NULL;
240
+ }
241
+out_free_pages:
242
+ dma_free_contiguous(dev, page, size);
243
+ return NULL;
137244 }
138245
139
-dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
140
- unsigned long offset, size_t size, enum dma_data_direction dir,
141
- unsigned long attrs)
246
+void dma_direct_free(struct device *dev, size_t size,
247
+ void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
142248 {
143
- dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset;
249
+ if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
250
+ !force_dma_unencrypted(dev)) {
251
+ /* cpu_addr is a struct page cookie, not a kernel address */
252
+ dma_free_contiguous(dev, cpu_addr, size);
253
+ return;
254
+ }
144255
145
- if (!check_addr(dev, dma_addr, size, __func__))
146
- return DIRECT_MAPPING_ERROR;
147
- return dma_addr;
256
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
257
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
258
+ !dev_is_dma_coherent(dev)) {
259
+ arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
260
+ return;
261
+ }
262
+
263
+ /* If cpu_addr is not from an atomic pool, dma_free_from_pool() fails */
264
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
265
+ dma_free_from_pool(dev, cpu_addr, PAGE_ALIGN(size)))
266
+ return;
267
+
268
+ if (force_dma_unencrypted(dev))
269
+ set_memory_encrypted((unsigned long)cpu_addr, PFN_UP(size));
270
+
271
+ if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr))
272
+ vunmap(cpu_addr);
273
+ else if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_CLEAR_UNCACHED))
274
+ arch_dma_clear_uncached(cpu_addr, size);
275
+
276
+ dma_free_contiguous(dev, dma_direct_to_page(dev, dma_addr), size);
148277 }
278
+
279
+struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
280
+ dma_addr_t *dma_handle, enum dma_data_direction dir, gfp_t gfp)
281
+{
282
+ struct page *page;
283
+ void *ret;
284
+
285
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
286
+ force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
287
+ return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
288
+
289
+ page = __dma_direct_alloc_pages(dev, size, gfp);
290
+ if (!page)
291
+ return NULL;
292
+ if (PageHighMem(page)) {
293
+ /*
294
+ * Depending on the cma= arguments and per-arch setup
295
+ * dma_alloc_contiguous could return highmem pages.
296
+ * Without remapping there is no way to return them here,
297
+ * so log an error and fail.
298
+ */
299
+ dev_info(dev, "Rejecting highmem page from CMA.\n");
300
+ goto out_free_pages;
301
+ }
302
+
303
+ ret = page_address(page);
304
+ if (force_dma_unencrypted(dev)) {
305
+ if (set_memory_decrypted((unsigned long)ret, PFN_UP(size)))
306
+ goto out_free_pages;
307
+ }
308
+ memset(ret, 0, size);
309
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
310
+ return page;
311
+out_free_pages:
312
+ dma_free_contiguous(dev, page, size);
313
+ return NULL;
314
+}
315
+
316
+void dma_direct_free_pages(struct device *dev, size_t size,
317
+ struct page *page, dma_addr_t dma_addr,
318
+ enum dma_data_direction dir)
319
+{
320
+ void *vaddr = page_address(page);
321
+
322
+ /* If cpu_addr is not from an atomic pool, dma_free_from_pool() fails */
323
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
324
+ dma_free_from_pool(dev, vaddr, size))
325
+ return;
326
+
327
+ if (force_dma_unencrypted(dev))
328
+ set_memory_encrypted((unsigned long)vaddr, PFN_UP(size));
329
+
330
+ dma_free_contiguous(dev, page, size);
331
+}
332
+
333
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \
334
+ defined(CONFIG_SWIOTLB)
335
+void dma_direct_sync_sg_for_device(struct device *dev,
336
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
337
+{
338
+ struct scatterlist *sg;
339
+ int i;
340
+
341
+ for_each_sg(sgl, sg, nents, i) {
342
+ phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
343
+
344
+ if (unlikely(is_swiotlb_buffer(paddr)))
345
+ swiotlb_tbl_sync_single(dev, paddr, sg->length,
346
+ dir, SYNC_FOR_DEVICE);
347
+
348
+ if (!dev_is_dma_coherent(dev))
349
+ arch_sync_dma_for_device(paddr, sg->length,
350
+ dir);
351
+ }
352
+}
353
+#endif
354
+
355
+#if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU) || \
356
+ defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_CPU_ALL) || \
357
+ defined(CONFIG_SWIOTLB)
358
+void dma_direct_sync_sg_for_cpu(struct device *dev,
359
+ struct scatterlist *sgl, int nents, enum dma_data_direction dir)
360
+{
361
+ struct scatterlist *sg;
362
+ int i;
363
+
364
+ for_each_sg(sgl, sg, nents, i) {
365
+ phys_addr_t paddr = dma_to_phys(dev, sg_dma_address(sg));
366
+
367
+ if (!dev_is_dma_coherent(dev))
368
+ arch_sync_dma_for_cpu(paddr, sg->length, dir);
369
+
370
+ if (unlikely(is_swiotlb_buffer(paddr)))
371
+ swiotlb_tbl_sync_single(dev, paddr, sg->length, dir,
372
+ SYNC_FOR_CPU);
373
+
374
+ if (dir == DMA_FROM_DEVICE)
375
+ arch_dma_mark_clean(paddr, sg->length);
376
+ }
377
+
378
+ if (!dev_is_dma_coherent(dev))
379
+ arch_sync_dma_for_cpu_all();
380
+}
381
+
382
+void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sgl,
383
+ int nents, enum dma_data_direction dir, unsigned long attrs)
384
+{
385
+ struct scatterlist *sg;
386
+ int i;
387
+
388
+ for_each_sg(sgl, sg, nents, i)
389
+ dma_direct_unmap_page(dev, sg->dma_address, sg_dma_len(sg), dir,
390
+ attrs);
391
+}
392
+#endif
149393
150394 int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
151395 enum dma_data_direction dir, unsigned long attrs)
....@@ -154,61 +398,151 @@
154398 struct scatterlist *sg;
155399
156400 for_each_sg(sgl, sg, nents, i) {
157
- BUG_ON(!sg_page(sg));
158
-
159
- sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg));
160
- if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__))
161
- return 0;
401
+ sg->dma_address = dma_direct_map_page(dev, sg_page(sg),
402
+ sg->offset, sg->length, dir, attrs);
403
+ if (sg->dma_address == DMA_MAPPING_ERROR)
404
+ goto out_unmap;
162405 sg_dma_len(sg) = sg->length;
163406 }
164407
165408 return nents;
409
+
410
+out_unmap:
411
+ dma_direct_unmap_sg(dev, sgl, i, dir, attrs | DMA_ATTR_SKIP_CPU_SYNC);
412
+ return 0;
413
+}
414
+
415
+dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
416
+ size_t size, enum dma_data_direction dir, unsigned long attrs)
417
+{
418
+ dma_addr_t dma_addr = paddr;
419
+
420
+ if (unlikely(!dma_capable(dev, dma_addr, size, false))) {
421
+ dev_err_once(dev,
422
+ "DMA addr %pad+%zu overflow (mask %llx, bus limit %llx).\n",
423
+ &dma_addr, size, *dev->dma_mask, dev->bus_dma_limit);
424
+ WARN_ON_ONCE(1);
425
+ return DMA_MAPPING_ERROR;
426
+ }
427
+
428
+ return dma_addr;
429
+}
430
+
431
+int dma_direct_get_sgtable(struct device *dev, struct sg_table *sgt,
432
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
433
+ unsigned long attrs)
434
+{
435
+ struct page *page = dma_direct_to_page(dev, dma_addr);
436
+ int ret;
437
+
438
+ ret = sg_alloc_table(sgt, 1, GFP_KERNEL);
439
+ if (!ret)
440
+ sg_set_page(sgt->sgl, page, PAGE_ALIGN(size), 0);
441
+ return ret;
442
+}
443
+
444
+bool dma_direct_can_mmap(struct device *dev)
445
+{
446
+ return dev_is_dma_coherent(dev) ||
447
+ IS_ENABLED(CONFIG_DMA_NONCOHERENT_MMAP);
448
+}
449
+
450
+int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma,
451
+ void *cpu_addr, dma_addr_t dma_addr, size_t size,
452
+ unsigned long attrs)
453
+{
454
+ unsigned long user_count = vma_pages(vma);
455
+ unsigned long count = PAGE_ALIGN(size) >> PAGE_SHIFT;
456
+ unsigned long pfn = PHYS_PFN(dma_to_phys(dev, dma_addr));
457
+ int ret = -ENXIO;
458
+
459
+ vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs);
460
+
461
+ if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret))
462
+ return ret;
463
+
464
+ if (vma->vm_pgoff >= count || user_count > count - vma->vm_pgoff)
465
+ return -ENXIO;
466
+ return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff,
467
+ user_count << PAGE_SHIFT, vma->vm_page_prot);
166468 }
167469
168470 int dma_direct_supported(struct device *dev, u64 mask)
169471 {
170
-#ifdef CONFIG_ZONE_DMA
171
- /*
172
- * This check needs to be against the actual bit mask value, so
173
- * use __phys_to_dma() here so that the SME encryption mask isn't
174
- * part of the check.
175
- */
176
- if (mask < __phys_to_dma(dev, DMA_BIT_MASK(ARCH_ZONE_DMA_BITS)))
177
- return 0;
178
-#else
472
+ u64 min_mask = (max_pfn - 1) << PAGE_SHIFT;
473
+
179474 /*
180475 * Because 32-bit DMA masks are so common we expect every architecture
181476 * to be able to satisfy them - either by not supporting more physical
182477 * memory, or by providing a ZONE_DMA32. If neither is the case, the
183478 * architecture needs to use an IOMMU instead of the direct mapping.
184
- *
185
- * This check needs to be against the actual bit mask value, so
186
- * use __phys_to_dma() here so that the SME encryption mask isn't
479
+ */
480
+ if (mask >= DMA_BIT_MASK(32))
481
+ return 1;
482
+
483
+ /*
484
+ * This check needs to be against the actual bit mask value, so use
485
+ * phys_to_dma_unencrypted() here so that the SME encryption mask isn't
187486 * part of the check.
188487 */
189
- if (mask < __phys_to_dma(dev, DMA_BIT_MASK(32)))
190
- return 0;
191
-#endif
192
- /*
193
- * Upstream PCI/PCIe bridges or SoC interconnects may not carry
194
- * as many DMA address bits as the device itself supports.
195
- */
196
- if (dev->bus_dma_mask && mask > dev->bus_dma_mask)
197
- return 0;
198
- return 1;
488
+ if (IS_ENABLED(CONFIG_ZONE_DMA))
489
+ min_mask = min_t(u64, min_mask, DMA_BIT_MASK(zone_dma_bits));
490
+ return mask >= phys_to_dma_unencrypted(dev, min_mask);
199491 }
200492
201
-int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
493
+size_t dma_direct_max_mapping_size(struct device *dev)
202494 {
203
- return dma_addr == DIRECT_MAPPING_ERROR;
495
+ /* If SWIOTLB is active, use its maximum mapping size */
496
+ if (is_swiotlb_active() &&
497
+ (dma_addressing_limited(dev) || swiotlb_force == SWIOTLB_FORCE))
498
+ return swiotlb_max_mapping_size(dev);
499
+ return SIZE_MAX;
204500 }
205501
206
-const struct dma_map_ops dma_direct_ops = {
207
- .alloc = dma_direct_alloc,
208
- .free = dma_direct_free,
209
- .map_page = dma_direct_map_page,
210
- .map_sg = dma_direct_map_sg,
211
- .dma_supported = dma_direct_supported,
212
- .mapping_error = dma_direct_mapping_error,
213
-};
214
-EXPORT_SYMBOL(dma_direct_ops);
502
+bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr)
503
+{
504
+ return !dev_is_dma_coherent(dev) ||
505
+ is_swiotlb_buffer(dma_to_phys(dev, dma_addr));
506
+}
507
+
508
+/**
509
+ * dma_direct_set_offset - Assign scalar offset for a single DMA range.
510
+ * @dev: device pointer; needed to "own" the alloced memory.
511
+ * @cpu_start: beginning of memory region covered by this offset.
512
+ * @dma_start: beginning of DMA/PCI region covered by this offset.
513
+ * @size: size of the region.
514
+ *
515
+ * This is for the simple case of a uniform offset which cannot
516
+ * be discovered by "dma-ranges".
517
+ *
518
+ * It returns -ENOMEM if out of memory, -EINVAL if a map
519
+ * already exists, 0 otherwise.
520
+ *
521
+ * Note: any call to this from a driver is a bug. The mapping needs
522
+ * to be described by the device tree or other firmware interfaces.
523
+ */
524
+int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
525
+ dma_addr_t dma_start, u64 size)
526
+{
527
+ struct bus_dma_region *map;
528
+ u64 offset = (u64)cpu_start - (u64)dma_start;
529
+
530
+ if (dev->dma_range_map) {
531
+ dev_err(dev, "attempt to add DMA range to existing map\n");
532
+ return -EINVAL;
533
+ }
534
+
535
+ if (!offset)
536
+ return 0;
537
+
538
+ map = kcalloc(2, sizeof(*map), GFP_KERNEL);
539
+ if (!map)
540
+ return -ENOMEM;
541
+ map[0].cpu_start = cpu_start;
542
+ map[0].dma_start = dma_start;
543
+ map[0].offset = offset;
544
+ map[0].size = size;
545
+ dev->dma_range_map = map;
546
+ return 0;
547
+}
548
+EXPORT_SYMBOL_GPL(dma_direct_set_offset);