Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'dma-mapping-5.8-6' of git://git.infradead.org/users/hch/dma-mapping into master
Pull dma-mapping fixes from Christoph Hellwig:
"Ensure we always have fully addressable memory in the dma coherent
pool (Nicolas Saenz Julienne)"
* tag 'dma-mapping-5.8-6' of git://git.infradead.org/users/hch/dma-mapping:
dma-pool: do not allocate pool memory from CMA
dma-pool: make sure atomic pool suits device
dma-pool: introduce dma_guess_pool()
dma-pool: get rid of dma_in_atomic_pool()
dma-direct: provide function to check physical memory area validity
+57
-35
+1
include/linux/dma-direct.h
+1
include/linux/dma-direct.h
···
69
69
u64 dma_direct_get_required_mask(struct device *dev);
70
70
gfp_t dma_direct_optimal_gfp_mask(struct device *dev, u64 dma_mask,
71
71
u64 *phys_mask);
72
+
bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size);
72
73
void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
73
74
gfp_t gfp, unsigned long attrs);
74
75
void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+1
-1
kernel/dma/direct.c
+1
-1
kernel/dma/direct.c
···
70
70
return 0;
71
71
}
72
72
73
-
static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
73
+
bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
74
74
{
75
75
return phys_to_dma_direct(dev, phys) + size - 1 <=
76
76
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
+55
-34
kernel/dma/pool.c
+55
-34
kernel/dma/pool.c
···
6
6
#include <linux/debugfs.h>
7
7
#include <linux/dma-direct.h>
8
8
#include <linux/dma-noncoherent.h>
9
-
#include <linux/dma-contiguous.h>
10
9
#include <linux/init.h>
11
10
#include <linux/genalloc.h>
12
11
#include <linux/set_memory.h>
···
68
69
69
70
do {
70
71
pool_size = 1 << (PAGE_SHIFT + order);
71
-
72
-
if (dev_get_cma_area(NULL))
73
-
page = dma_alloc_from_contiguous(NULL, 1 << order,
74
-
order, false);
75
-
else
76
-
page = alloc_pages(gfp, order);
72
+
page = alloc_pages(gfp, order);
77
73
} while (!page && order-- > 0);
78
74
if (!page)
79
75
goto out;
···
112
118
dma_common_free_remap(addr, pool_size);
113
119
#endif
114
120
free_page: __maybe_unused
115
-
if (!dma_release_from_contiguous(NULL, page, 1 << order))
116
-
__free_pages(page, order);
121
+
__free_pages(page, order);
117
122
out:
118
123
return ret;
119
124
}
···
196
203
}
197
204
postcore_initcall(dma_atomic_pool_init);
198
205
199
-
static inline struct gen_pool *dev_to_pool(struct device *dev)
206
+
static inline struct gen_pool *dma_guess_pool_from_device(struct device *dev)
200
207
{
201
208
u64 phys_mask;
202
209
gfp_t gfp;
···
210
217
return atomic_pool_kernel;
211
218
}
212
219
213
-
static bool dma_in_atomic_pool(struct device *dev, void *start, size_t size)
220
+
static inline struct gen_pool *dma_get_safer_pool(struct gen_pool *bad_pool)
214
221
{
215
-
struct gen_pool *pool = dev_to_pool(dev);
222
+
if (bad_pool == atomic_pool_kernel)
223
+
return atomic_pool_dma32 ? : atomic_pool_dma;
216
224
217
-
if (unlikely(!pool))
218
-
return false;
219
-
return gen_pool_has_addr(pool, (unsigned long)start, size);
225
+
if (bad_pool == atomic_pool_dma32)
226
+
return atomic_pool_dma;
227
+
228
+
return NULL;
229
+
}
230
+
231
+
static inline struct gen_pool *dma_guess_pool(struct device *dev,
232
+
struct gen_pool *bad_pool)
233
+
{
234
+
if (bad_pool)
235
+
return dma_get_safer_pool(bad_pool);
236
+
237
+
return dma_guess_pool_from_device(dev);
220
238
}
221
239
222
240
void *dma_alloc_from_pool(struct device *dev, size_t size,
223
241
struct page **ret_page, gfp_t flags)
224
242
{
225
-
struct gen_pool *pool = dev_to_pool(dev);
226
-
unsigned long val;
243
+
struct gen_pool *pool = NULL;
244
+
unsigned long val = 0;
227
245
void *ptr = NULL;
246
+
phys_addr_t phys;
228
247
229
-
if (!pool) {
230
-
WARN(1, "%pGg atomic pool not initialised!\n", &flags);
231
-
return NULL;
248
+
while (1) {
249
+
pool = dma_guess_pool(dev, pool);
250
+
if (!pool) {
251
+
WARN(1, "Failed to get suitable pool for %s\n",
252
+
dev_name(dev));
253
+
break;
254
+
}
255
+
256
+
val = gen_pool_alloc(pool, size);
257
+
if (!val)
258
+
continue;
259
+
260
+
phys = gen_pool_virt_to_phys(pool, val);
261
+
if (dma_coherent_ok(dev, phys, size))
262
+
break;
263
+
264
+
gen_pool_free(pool, val, size);
265
+
val = 0;
232
266
}
233
267
234
-
val = gen_pool_alloc(pool, size);
235
-
if (likely(val)) {
236
-
phys_addr_t phys = gen_pool_virt_to_phys(pool, val);
237
268
269
+
if (val) {
238
270
*ret_page = pfn_to_page(__phys_to_pfn(phys));
239
271
ptr = (void *)val;
240
272
memset(ptr, 0, size);
241
-
} else {
242
-
WARN_ONCE(1, "DMA coherent pool depleted, increase size "
243
-
"(recommended min coherent_pool=%zuK)\n",
244
-
gen_pool_size(pool) >> 9);
273
+
274
+
if (gen_pool_avail(pool) < atomic_pool_size)
275
+
schedule_work(&atomic_pool_work);
245
276
}
246
-
if (gen_pool_avail(pool) < atomic_pool_size)
247
-
schedule_work(&atomic_pool_work);
248
277
249
278
return ptr;
250
279
}
251
280
252
281
bool dma_free_from_pool(struct device *dev, void *start, size_t size)
253
282
{
254
-
struct gen_pool *pool = dev_to_pool(dev);
283
+
struct gen_pool *pool = NULL;
255
284
256
-
if (!dma_in_atomic_pool(dev, start, size))
257
-
return false;
258
-
gen_pool_free(pool, (unsigned long)start, size);
259
-
return true;
285
+
while (1) {
286
+
pool = dma_guess_pool(dev, pool);
287
+
if (!pool)
288
+
return false;
289
+
290
+
if (gen_pool_has_addr(pool, (unsigned long)start, size)) {
291
+
gen_pool_free(pool, (unsigned long)start, size);
292
+
return true;
293
+
}
294
+
}
260
295
}