2 * Dynamic DMA mapping support.
4 * This implementation is for IA-64 and EM64T platforms that do not support
5 * 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>
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.
14 * 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.
19 #include <linux/cache.h>
20 #include <linux/dma-mapping.h>
22 #include <linux/module.h>
23 #include <linux/spinlock.h>
24 #include <linux/string.h>
25 #include <linux/types.h>
26 #include <linux/ctype.h>
30 #include <asm/scatterlist.h>
32 #include <linux/init.h>
33 #include <linux/bootmem.h>
35 #define OFFSET(val,align) ((unsigned long) \
36 ( (val) & ( (align) - 1)))
38 #define SG_ENT_VIRT_ADDRESS(sg) (page_address((sg)->page) + (sg)->offset)
39 #define SG_ENT_PHYS_ADDRESS(SG) virt_to_phys(SG_ENT_VIRT_ADDRESS(SG))
42 * Maximum allowable number of contiguous slabs to map,
43 * must be a power of 2. What is the appropriate value ?
44 * The complexity of {map,unmap}_single is linearly dependent on this value.
46 #define IO_TLB_SEGSIZE 128
49 * log of the size of each IO TLB slab. The number of slabs is command line
52 #define IO_TLB_SHIFT 11
54 #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
57 * Minimum IO TLB size to bother booting with. Systems with mainly
58 * 64bit capable cards will only lightly use the swiotlb. If we can't
59 * allocate a contiguous 1MB, we're probably in trouble anyway.
61 #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
64 * Enumeration for sync targets
66 enum dma_sync_target
{
74 * Used to do a quick range check in swiotlb_unmap_single and
75 * swiotlb_sync_single_*, to see if the memory was in fact allocated by this
78 static char *io_tlb_start
, *io_tlb_end
;
81 * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
82 * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
84 static unsigned long io_tlb_nslabs
;
87 * When the IOMMU overflows we return a fallback buffer. This sets the size.
89 static unsigned long io_tlb_overflow
= 32*1024;
91 void *io_tlb_overflow_buffer
;
94 * This is a free list describing the number of free entries available from
97 static unsigned int *io_tlb_list
;
98 static unsigned int io_tlb_index
;
101 * We need to save away the original address corresponding to a mapped entry
102 * for the sync operations.
104 static unsigned char **io_tlb_orig_addr
;
107 * Protect the above data structures in the map and unmap calls
109 static DEFINE_SPINLOCK(io_tlb_lock
);
112 setup_io_tlb_npages(char *str
)
115 io_tlb_nslabs
= simple_strtoul(str
, &str
, 0);
116 /* avoid tail segment of size < IO_TLB_SEGSIZE */
117 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
121 if (!strcmp(str
, "force"))
125 __setup("swiotlb=", setup_io_tlb_npages
);
126 /* make io_tlb_overflow tunable too? */
129 * Statically reserve bounce buffer space and initialize bounce buffer data
130 * structures for the software IO TLB used to implement the DMA API.
133 swiotlb_init_with_default_size (size_t default_size
)
137 if (!io_tlb_nslabs
) {
138 io_tlb_nslabs
= (default_size
>> IO_TLB_SHIFT
);
139 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
143 * Get IO TLB memory from the low pages
145 io_tlb_start
= alloc_bootmem_low_pages(io_tlb_nslabs
* (1 << IO_TLB_SHIFT
));
147 panic("Cannot allocate SWIOTLB buffer");
148 io_tlb_end
= io_tlb_start
+ io_tlb_nslabs
* (1 << IO_TLB_SHIFT
);
151 * Allocate and initialize the free list array. This array is used
152 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
153 * between io_tlb_start and io_tlb_end.
155 io_tlb_list
= alloc_bootmem(io_tlb_nslabs
* sizeof(int));
156 for (i
= 0; i
< io_tlb_nslabs
; i
++)
157 io_tlb_list
[i
] = IO_TLB_SEGSIZE
- OFFSET(i
, IO_TLB_SEGSIZE
);
159 io_tlb_orig_addr
= alloc_bootmem(io_tlb_nslabs
* sizeof(char *));
162 * Get the overflow emergency buffer
164 io_tlb_overflow_buffer
= alloc_bootmem_low(io_tlb_overflow
);
165 printk(KERN_INFO
"Placing software IO TLB between 0x%lx - 0x%lx\n",
166 virt_to_phys(io_tlb_start
), virt_to_phys(io_tlb_end
));
172 swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */
176 * Systems with larger DMA zones (those that don't support ISA) can
177 * initialize the swiotlb later using the slab allocator if needed.
178 * This should be just like above, but with some error catching.
181 swiotlb_late_init_with_default_size (size_t default_size
)
183 unsigned long i
, req_nslabs
= io_tlb_nslabs
;
186 if (!io_tlb_nslabs
) {
187 io_tlb_nslabs
= (default_size
>> IO_TLB_SHIFT
);
188 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
192 * Get IO TLB memory from the low pages
194 order
= get_order(io_tlb_nslabs
* (1 << IO_TLB_SHIFT
));
195 io_tlb_nslabs
= SLABS_PER_PAGE
<< order
;
197 while ((SLABS_PER_PAGE
<< order
) > IO_TLB_MIN_SLABS
) {
198 io_tlb_start
= (char *)__get_free_pages(GFP_DMA
| __GFP_NOWARN
,
208 if (order
!= get_order(io_tlb_nslabs
* (1 << IO_TLB_SHIFT
))) {
209 printk(KERN_WARNING
"Warning: only able to allocate %ld MB "
210 "for software IO TLB\n", (PAGE_SIZE
<< order
) >> 20);
211 io_tlb_nslabs
= SLABS_PER_PAGE
<< order
;
213 io_tlb_end
= io_tlb_start
+ io_tlb_nslabs
* (1 << IO_TLB_SHIFT
);
214 memset(io_tlb_start
, 0, io_tlb_nslabs
* (1 << IO_TLB_SHIFT
));
217 * Allocate and initialize the free list array. This array is used
218 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
219 * between io_tlb_start and io_tlb_end.
221 io_tlb_list
= (unsigned int *)__get_free_pages(GFP_KERNEL
,
222 get_order(io_tlb_nslabs
* sizeof(int)));
226 for (i
= 0; i
< io_tlb_nslabs
; i
++)
227 io_tlb_list
[i
] = IO_TLB_SEGSIZE
- OFFSET(i
, IO_TLB_SEGSIZE
);
230 io_tlb_orig_addr
= (unsigned char **)__get_free_pages(GFP_KERNEL
,
231 get_order(io_tlb_nslabs
* sizeof(char *)));
232 if (!io_tlb_orig_addr
)
235 memset(io_tlb_orig_addr
, 0, io_tlb_nslabs
* sizeof(char *));
238 * Get the overflow emergency buffer
240 io_tlb_overflow_buffer
= (void *)__get_free_pages(GFP_DMA
,
241 get_order(io_tlb_overflow
));
242 if (!io_tlb_overflow_buffer
)
245 printk(KERN_INFO
"Placing %ldMB software IO TLB between 0x%lx - "
246 "0x%lx\n", (io_tlb_nslabs
* (1 << IO_TLB_SHIFT
)) >> 20,
247 virt_to_phys(io_tlb_start
), virt_to_phys(io_tlb_end
));
252 free_pages((unsigned long)io_tlb_orig_addr
, get_order(io_tlb_nslabs
*
254 io_tlb_orig_addr
= NULL
;
256 free_pages((unsigned long)io_tlb_list
, get_order(io_tlb_nslabs
*
261 free_pages((unsigned long)io_tlb_start
, order
);
264 io_tlb_nslabs
= req_nslabs
;
269 address_needs_mapping(struct device
*hwdev
, dma_addr_t addr
)
271 dma_addr_t mask
= 0xffffffff;
272 /* If the device has a mask, use it, otherwise default to 32 bits */
273 if (hwdev
&& hwdev
->dma_mask
)
274 mask
= *hwdev
->dma_mask
;
275 return (addr
& ~mask
) != 0;
279 * Allocates bounce buffer and returns its kernel virtual address.
282 map_single(struct device
*hwdev
, char *buffer
, size_t size
, int dir
)
286 unsigned int nslots
, stride
, index
, wrap
;
290 * For mappings greater than a page, we limit the stride (and
291 * hence alignment) to a page size.
293 nslots
= ALIGN(size
, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
;
294 if (size
> PAGE_SIZE
)
295 stride
= (1 << (PAGE_SHIFT
- IO_TLB_SHIFT
));
303 * Find suitable number of IO TLB entries size that will fit this
304 * request and allocate a buffer from that IO TLB pool.
306 spin_lock_irqsave(&io_tlb_lock
, flags
);
308 wrap
= index
= ALIGN(io_tlb_index
, stride
);
310 if (index
>= io_tlb_nslabs
)
315 * If we find a slot that indicates we have 'nslots'
316 * number of contiguous buffers, we allocate the
317 * buffers from that slot and mark the entries as '0'
318 * indicating unavailable.
320 if (io_tlb_list
[index
] >= nslots
) {
323 for (i
= index
; i
< (int) (index
+ nslots
); i
++)
325 for (i
= index
- 1; (OFFSET(i
, IO_TLB_SEGSIZE
) != IO_TLB_SEGSIZE
-1) && io_tlb_list
[i
]; i
--)
326 io_tlb_list
[i
] = ++count
;
327 dma_addr
= io_tlb_start
+ (index
<< IO_TLB_SHIFT
);
330 * Update the indices to avoid searching in
333 io_tlb_index
= ((index
+ nslots
) < io_tlb_nslabs
334 ? (index
+ nslots
) : 0);
339 if (index
>= io_tlb_nslabs
)
341 } while (index
!= wrap
);
343 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
347 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
350 * Save away the mapping from the original address to the DMA address.
351 * This is needed when we sync the memory. Then we sync the buffer if
354 io_tlb_orig_addr
[index
] = buffer
;
355 if (dir
== DMA_TO_DEVICE
|| dir
== DMA_BIDIRECTIONAL
)
356 memcpy(dma_addr
, buffer
, size
);
362 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
365 unmap_single(struct device
*hwdev
, char *dma_addr
, size_t size
, int dir
)
368 int i
, count
, nslots
= ALIGN(size
, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
;
369 int index
= (dma_addr
- io_tlb_start
) >> IO_TLB_SHIFT
;
370 char *buffer
= io_tlb_orig_addr
[index
];
373 * First, sync the memory before unmapping the entry
375 if (buffer
&& ((dir
== DMA_FROM_DEVICE
) || (dir
== DMA_BIDIRECTIONAL
)))
377 * bounce... copy the data back into the original buffer * and
378 * delete the bounce buffer.
380 memcpy(buffer
, dma_addr
, size
);
383 * Return the buffer to the free list by setting the corresponding
384 * entries to indicate the number of contigous entries available.
385 * While returning the entries to the free list, we merge the entries
386 * with slots below and above the pool being returned.
388 spin_lock_irqsave(&io_tlb_lock
, flags
);
390 count
= ((index
+ nslots
) < ALIGN(index
+ 1, IO_TLB_SEGSIZE
) ?
391 io_tlb_list
[index
+ nslots
] : 0);
393 * Step 1: return the slots to the free list, merging the
394 * slots with superceeding slots
396 for (i
= index
+ nslots
- 1; i
>= index
; i
--)
397 io_tlb_list
[i
] = ++count
;
399 * Step 2: merge the returned slots with the preceding slots,
400 * if available (non zero)
402 for (i
= index
- 1; (OFFSET(i
, IO_TLB_SEGSIZE
) != IO_TLB_SEGSIZE
-1) && io_tlb_list
[i
]; i
--)
403 io_tlb_list
[i
] = ++count
;
405 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
409 sync_single(struct device
*hwdev
, char *dma_addr
, size_t size
,
412 int index
= (dma_addr
- io_tlb_start
) >> IO_TLB_SHIFT
;
413 char *buffer
= io_tlb_orig_addr
[index
];
417 if (likely(dir
== DMA_FROM_DEVICE
|| dir
== DMA_BIDIRECTIONAL
))
418 memcpy(buffer
, dma_addr
, size
);
419 else if (dir
!= DMA_TO_DEVICE
)
422 case SYNC_FOR_DEVICE
:
423 if (likely(dir
== DMA_TO_DEVICE
|| dir
== DMA_BIDIRECTIONAL
))
424 memcpy(dma_addr
, buffer
, size
);
425 else if (dir
!= DMA_FROM_DEVICE
)
434 swiotlb_alloc_coherent(struct device
*hwdev
, size_t size
,
435 dma_addr_t
*dma_handle
, gfp_t flags
)
437 unsigned long dev_addr
;
439 int order
= get_order(size
);
442 * XXX fix me: the DMA API should pass us an explicit DMA mask
443 * instead, or use ZONE_DMA32 (ia64 overloads ZONE_DMA to be a ~32
444 * bit range instead of a 16MB one).
448 ret
= (void *)__get_free_pages(flags
, order
);
449 if (ret
&& address_needs_mapping(hwdev
, virt_to_phys(ret
))) {
451 * The allocated memory isn't reachable by the device.
452 * Fall back on swiotlb_map_single().
454 free_pages((unsigned long) ret
, order
);
459 * We are either out of memory or the device can't DMA
460 * to GFP_DMA memory; fall back on
461 * swiotlb_map_single(), which will grab memory from
462 * the lowest available address range.
465 handle
= swiotlb_map_single(NULL
, NULL
, size
, DMA_FROM_DEVICE
);
466 if (swiotlb_dma_mapping_error(handle
))
469 ret
= phys_to_virt(handle
);
472 memset(ret
, 0, size
);
473 dev_addr
= virt_to_phys(ret
);
475 /* Confirm address can be DMA'd by device */
476 if (address_needs_mapping(hwdev
, dev_addr
)) {
477 printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016lx\n",
478 (unsigned long long)*hwdev
->dma_mask
, dev_addr
);
479 panic("swiotlb_alloc_coherent: allocated memory is out of "
482 *dma_handle
= dev_addr
;
487 swiotlb_free_coherent(struct device
*hwdev
, size_t size
, void *vaddr
,
488 dma_addr_t dma_handle
)
490 if (!(vaddr
>= (void *)io_tlb_start
491 && vaddr
< (void *)io_tlb_end
))
492 free_pages((unsigned long) vaddr
, get_order(size
));
494 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
495 swiotlb_unmap_single (hwdev
, dma_handle
, size
, DMA_TO_DEVICE
);
499 swiotlb_full(struct device
*dev
, size_t size
, int dir
, int do_panic
)
502 * Ran out of IOMMU space for this operation. This is very bad.
503 * Unfortunately the drivers cannot handle this operation properly.
504 * unless they check for dma_mapping_error (most don't)
505 * When the mapping is small enough return a static buffer to limit
506 * the damage, or panic when the transfer is too big.
508 printk(KERN_ERR
"DMA: Out of SW-IOMMU space for %lu bytes at "
509 "device %s\n", size
, dev
? dev
->bus_id
: "?");
511 if (size
> io_tlb_overflow
&& do_panic
) {
512 if (dir
== DMA_FROM_DEVICE
|| dir
== DMA_BIDIRECTIONAL
)
513 panic("DMA: Memory would be corrupted\n");
514 if (dir
== DMA_TO_DEVICE
|| dir
== DMA_BIDIRECTIONAL
)
515 panic("DMA: Random memory would be DMAed\n");
520 * Map a single buffer of the indicated size for DMA in streaming mode. The
521 * physical address to use is returned.
523 * Once the device is given the dma address, the device owns this memory until
524 * either swiotlb_unmap_single or swiotlb_dma_sync_single is performed.
527 swiotlb_map_single(struct device
*hwdev
, void *ptr
, size_t size
, int dir
)
529 unsigned long dev_addr
= virt_to_phys(ptr
);
535 * If the pointer passed in happens to be in the device's DMA window,
536 * we can safely return the device addr and not worry about bounce
539 if (!address_needs_mapping(hwdev
, dev_addr
) && !swiotlb_force
)
543 * Oh well, have to allocate and map a bounce buffer.
545 map
= map_single(hwdev
, ptr
, size
, dir
);
547 swiotlb_full(hwdev
, size
, dir
, 1);
548 map
= io_tlb_overflow_buffer
;
551 dev_addr
= virt_to_phys(map
);
554 * Ensure that the address returned is DMA'ble
556 if (address_needs_mapping(hwdev
, dev_addr
))
557 panic("map_single: bounce buffer is not DMA'ble");
563 * Since DMA is i-cache coherent, any (complete) pages that were written via
564 * DMA can be marked as "clean" so that lazy_mmu_prot_update() doesn't have to
565 * flush them when they get mapped into an executable vm-area.
568 mark_clean(void *addr
, size_t size
)
570 unsigned long pg_addr
, end
;
572 pg_addr
= PAGE_ALIGN((unsigned long) addr
);
573 end
= (unsigned long) addr
+ size
;
574 while (pg_addr
+ PAGE_SIZE
<= end
) {
575 struct page
*page
= virt_to_page(pg_addr
);
576 set_bit(PG_arch_1
, &page
->flags
);
577 pg_addr
+= PAGE_SIZE
;
582 * Unmap a single streaming mode DMA translation. The dma_addr and size must
583 * match what was provided for in a previous swiotlb_map_single call. All
584 * other usages are undefined.
586 * After this call, reads by the cpu to the buffer are guaranteed to see
587 * whatever the device wrote there.
590 swiotlb_unmap_single(struct device
*hwdev
, dma_addr_t dev_addr
, size_t size
,
593 char *dma_addr
= phys_to_virt(dev_addr
);
597 if (dma_addr
>= io_tlb_start
&& dma_addr
< io_tlb_end
)
598 unmap_single(hwdev
, dma_addr
, size
, dir
);
599 else if (dir
== DMA_FROM_DEVICE
)
600 mark_clean(dma_addr
, size
);
604 * Make physical memory consistent for a single streaming mode DMA translation
607 * If you perform a swiotlb_map_single() but wish to interrogate the buffer
608 * using the cpu, yet do not wish to teardown the dma mapping, you must
609 * call this function before doing so. At the next point you give the dma
610 * address back to the card, you must first perform a
611 * swiotlb_dma_sync_for_device, and then the device again owns the buffer
614 swiotlb_sync_single(struct device
*hwdev
, dma_addr_t dev_addr
,
615 size_t size
, int dir
, int target
)
617 char *dma_addr
= phys_to_virt(dev_addr
);
621 if (dma_addr
>= io_tlb_start
&& dma_addr
< io_tlb_end
)
622 sync_single(hwdev
, dma_addr
, size
, dir
, target
);
623 else if (dir
== DMA_FROM_DEVICE
)
624 mark_clean(dma_addr
, size
);
628 swiotlb_sync_single_for_cpu(struct device
*hwdev
, dma_addr_t dev_addr
,
629 size_t size
, int dir
)
631 swiotlb_sync_single(hwdev
, dev_addr
, size
, dir
, SYNC_FOR_CPU
);
635 swiotlb_sync_single_for_device(struct device
*hwdev
, dma_addr_t dev_addr
,
636 size_t size
, int dir
)
638 swiotlb_sync_single(hwdev
, dev_addr
, size
, dir
, SYNC_FOR_DEVICE
);
642 * Same as above, but for a sub-range of the mapping.
645 swiotlb_sync_single_range(struct device
*hwdev
, dma_addr_t dev_addr
,
646 unsigned long offset
, size_t size
,
649 char *dma_addr
= phys_to_virt(dev_addr
) + offset
;
653 if (dma_addr
>= io_tlb_start
&& dma_addr
< io_tlb_end
)
654 sync_single(hwdev
, dma_addr
, size
, dir
, target
);
655 else if (dir
== DMA_FROM_DEVICE
)
656 mark_clean(dma_addr
, size
);
660 swiotlb_sync_single_range_for_cpu(struct device
*hwdev
, dma_addr_t dev_addr
,
661 unsigned long offset
, size_t size
, int dir
)
663 swiotlb_sync_single_range(hwdev
, dev_addr
, offset
, size
, dir
,
668 swiotlb_sync_single_range_for_device(struct device
*hwdev
, dma_addr_t dev_addr
,
669 unsigned long offset
, size_t size
, int dir
)
671 swiotlb_sync_single_range(hwdev
, dev_addr
, offset
, size
, dir
,
676 * Map a set of buffers described by scatterlist in streaming mode for DMA.
677 * This is the scatter-gather version of the above swiotlb_map_single
678 * interface. Here the scatter gather list elements are each tagged with the
679 * appropriate dma address and length. They are obtained via
680 * sg_dma_{address,length}(SG).
682 * NOTE: An implementation may be able to use a smaller number of
683 * DMA address/length pairs than there are SG table elements.
684 * (for example via virtual mapping capabilities)
685 * The routine returns the number of addr/length pairs actually
686 * used, at most nents.
688 * Device ownership issues as mentioned above for swiotlb_map_single are the
692 swiotlb_map_sg(struct device
*hwdev
, struct scatterlist
*sg
, int nelems
,
696 unsigned long dev_addr
;
702 for (i
= 0; i
< nelems
; i
++, sg
++) {
703 addr
= SG_ENT_VIRT_ADDRESS(sg
);
704 dev_addr
= virt_to_phys(addr
);
705 if (swiotlb_force
|| address_needs_mapping(hwdev
, dev_addr
)) {
706 void *map
= map_single(hwdev
, addr
, sg
->length
, dir
);
707 sg
->dma_address
= virt_to_bus(map
);
709 /* Don't panic here, we expect map_sg users
710 to do proper error handling. */
711 swiotlb_full(hwdev
, sg
->length
, dir
, 0);
712 swiotlb_unmap_sg(hwdev
, sg
- i
, i
, dir
);
713 sg
[0].dma_length
= 0;
717 sg
->dma_address
= dev_addr
;
718 sg
->dma_length
= sg
->length
;
724 * Unmap a set of streaming mode DMA translations. Again, cpu read rules
725 * concerning calls here are the same as for swiotlb_unmap_single() above.
728 swiotlb_unmap_sg(struct device
*hwdev
, struct scatterlist
*sg
, int nelems
,
736 for (i
= 0; i
< nelems
; i
++, sg
++)
737 if (sg
->dma_address
!= SG_ENT_PHYS_ADDRESS(sg
))
738 unmap_single(hwdev
, (void *) phys_to_virt(sg
->dma_address
), sg
->dma_length
, dir
);
739 else if (dir
== DMA_FROM_DEVICE
)
740 mark_clean(SG_ENT_VIRT_ADDRESS(sg
), sg
->dma_length
);
744 * Make physical memory consistent for a set of streaming mode DMA translations
747 * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
751 swiotlb_sync_sg(struct device
*hwdev
, struct scatterlist
*sg
,
752 int nelems
, int dir
, int target
)
759 for (i
= 0; i
< nelems
; i
++, sg
++)
760 if (sg
->dma_address
!= SG_ENT_PHYS_ADDRESS(sg
))
761 sync_single(hwdev
, phys_to_virt(sg
->dma_address
),
762 sg
->dma_length
, dir
, target
);
766 swiotlb_sync_sg_for_cpu(struct device
*hwdev
, struct scatterlist
*sg
,
769 swiotlb_sync_sg(hwdev
, sg
, nelems
, dir
, SYNC_FOR_CPU
);
773 swiotlb_sync_sg_for_device(struct device
*hwdev
, struct scatterlist
*sg
,
776 swiotlb_sync_sg(hwdev
, sg
, nelems
, dir
, SYNC_FOR_DEVICE
);
780 swiotlb_dma_mapping_error(dma_addr_t dma_addr
)
782 return (dma_addr
== virt_to_phys(io_tlb_overflow_buffer
));
786 * Return whether the given device DMA address mask can be supported
787 * properly. For example, if your device can only drive the low 24-bits
788 * during bus mastering, then you would pass 0x00ffffff as the mask to
792 swiotlb_dma_supported (struct device
*hwdev
, u64 mask
)
794 return (virt_to_phys (io_tlb_end
) - 1) <= mask
;
797 EXPORT_SYMBOL(swiotlb_init
);
798 EXPORT_SYMBOL(swiotlb_map_single
);
799 EXPORT_SYMBOL(swiotlb_unmap_single
);
800 EXPORT_SYMBOL(swiotlb_map_sg
);
801 EXPORT_SYMBOL(swiotlb_unmap_sg
);
802 EXPORT_SYMBOL(swiotlb_sync_single_for_cpu
);
803 EXPORT_SYMBOL(swiotlb_sync_single_for_device
);
804 EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu
);
805 EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device
);
806 EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu
);
807 EXPORT_SYMBOL(swiotlb_sync_sg_for_device
);
808 EXPORT_SYMBOL(swiotlb_dma_mapping_error
);
809 EXPORT_SYMBOL(swiotlb_alloc_coherent
);
810 EXPORT_SYMBOL(swiotlb_free_coherent
);
811 EXPORT_SYMBOL(swiotlb_dma_supported
);