Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
swiotlb: provide swiotlb_init variants that remap the buffer
To shared more code between swiotlb and xen-swiotlb, offer a
swiotlb_init_remap interface and add a remap callback to
swiotlb_init_late that will allow Xen to remap the buffer without
duplicating much of the logic.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Tested-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>
+38
-5
+1
-1
arch/x86/pci/sta2x11-fixup.c
+1
-1
arch/x86/pci/sta2x11-fixup.c
···
57
57
int size = STA2X11_SWIOTLB_SIZE;
58
58
/* First instance: register your own swiotlb area */
59
59
dev_info(&pdev->dev, "Using SWIOTLB (size %i)\n", size);
60
-
if (swiotlb_init_late(size, GFP_DMA))
60
+
if (swiotlb_init_late(size, GFP_DMA, NULL))
61
61
dev_emerg(&pdev->dev, "init swiotlb failed\n");
62
62
}
63
63
list_add(&instance->list, &sta2x11_instance_list);
+4
-1
include/linux/swiotlb.h
+4
-1
include/linux/swiotlb.h
···
36
36
37
37
int swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, unsigned int flags);
38
38
unsigned long swiotlb_size_or_default(void);
39
+
void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
40
+
int (*remap)(void *tlb, unsigned long nslabs));
41
+
int swiotlb_init_late(size_t size, gfp_t gfp_mask,
42
+
int (*remap)(void *tlb, unsigned long nslabs));
39
43
extern int swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs);
40
-
int swiotlb_init_late(size_t size, gfp_t gfp_mask);
41
44
extern void __init swiotlb_update_mem_attributes(void);
42
45
43
46
phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys,
+33
-3
kernel/dma/swiotlb.c
+33
-3
kernel/dma/swiotlb.c
···
256
256
* Statically reserve bounce buffer space and initialize bounce buffer data
257
257
* structures for the software IO TLB used to implement the DMA API.
258
258
*/
259
-
void __init swiotlb_init(bool addressing_limit, unsigned int flags)
259
+
void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
260
+
int (*remap)(void *tlb, unsigned long nslabs))
260
261
{
261
-
size_t bytes = PAGE_ALIGN(default_nslabs << IO_TLB_SHIFT);
262
+
unsigned long nslabs = default_nslabs;
263
+
size_t bytes;
262
264
void *tlb;
263
265
264
266
if (!addressing_limit && !swiotlb_force_bounce)
···
273
271
* allow to pick a location everywhere for hypervisors with guest
274
272
* memory encryption.
275
273
*/
274
+
retry:
275
+
bytes = PAGE_ALIGN(default_nslabs << IO_TLB_SHIFT);
276
276
if (flags & SWIOTLB_ANY)
277
277
tlb = memblock_alloc(bytes, PAGE_SIZE);
278
278
else
279
279
tlb = memblock_alloc_low(bytes, PAGE_SIZE);
280
280
if (!tlb)
281
281
goto fail;
282
+
if (remap && remap(tlb, nslabs) < 0) {
283
+
memblock_free(tlb, PAGE_ALIGN(bytes));
284
+
285
+
nslabs = ALIGN(nslabs >> 1, IO_TLB_SEGSIZE);
286
+
if (nslabs < IO_TLB_MIN_SLABS)
287
+
panic("%s: Failed to remap %zu bytes\n",
288
+
__func__, bytes);
289
+
goto retry;
290
+
}
282
291
if (swiotlb_init_with_tbl(tlb, default_nslabs, flags))
283
292
goto fail_free_mem;
284
293
return;
···
300
287
pr_warn("Cannot allocate buffer");
301
288
}
302
289
290
+
void __init swiotlb_init(bool addressing_limit, unsigned int flags)
291
+
{
292
+
return swiotlb_init_remap(addressing_limit, flags, NULL);
293
+
}
294
+
303
295
/*
304
296
* Systems with larger DMA zones (those that don't support ISA) can
305
297
* initialize the swiotlb later using the slab allocator if needed.
306
298
* This should be just like above, but with some error catching.
307
299
*/
308
-
int swiotlb_init_late(size_t size, gfp_t gfp_mask)
300
+
int swiotlb_init_late(size_t size, gfp_t gfp_mask,
301
+
int (*remap)(void *tlb, unsigned long nslabs))
309
302
{
310
303
unsigned long nslabs = ALIGN(size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE);
311
304
unsigned long bytes;
···
322
303
if (swiotlb_force_disable)
323
304
return 0;
324
305
306
+
retry:
325
307
order = get_order(nslabs << IO_TLB_SHIFT);
326
308
nslabs = SLABS_PER_PAGE << order;
327
309
bytes = nslabs << IO_TLB_SHIFT;
···
342
322
pr_warn("only able to allocate %ld MB\n",
343
323
(PAGE_SIZE << order) >> 20);
344
324
nslabs = SLABS_PER_PAGE << order;
325
+
}
326
+
if (remap)
327
+
rc = remap(vstart, nslabs);
328
+
if (rc) {
329
+
free_pages((unsigned long)vstart, order);
330
+
331
+
nslabs = ALIGN(nslabs >> 1, IO_TLB_SEGSIZE);
332
+
if (nslabs < IO_TLB_MIN_SLABS)
333
+
return rc;
334
+
goto retry;
345
335
}
346
336
rc = swiotlb_late_init_with_tbl(vstart, nslabs);
347
337
if (rc)