2 * Dynamic DMA mapping support.
4 * This implementation is a fallback for 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.
17 * 08/12/11 beckyb Add highmem support
20 #include <linux/cache.h>
21 #include <linux/dma-mapping.h>
23 #include <linux/module.h>
24 #include <linux/spinlock.h>
25 #include <linux/string.h>
26 #include <linux/swiotlb.h>
27 #include <linux/pfn.h>
28 #include <linux/types.h>
29 #include <linux/ctype.h>
30 #include <linux/highmem.h>
34 #include <asm/scatterlist.h>
36 #include <linux/init.h>
37 #include <linux/bootmem.h>
38 #include <linux/iommu-helper.h>
40 #define OFFSET(val,align) ((unsigned long) \
41 ( (val) & ( (align) - 1)))
43 #define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))
46 * Minimum IO TLB size to bother booting with. Systems with mainly
47 * 64bit capable cards will only lightly use the swiotlb. If we can't
48 * allocate a contiguous 1MB, we're probably in trouble anyway.
50 #define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
53 * Enumeration for sync targets
55 enum dma_sync_target
{
63 * Used to do a quick range check in unmap_single and
64 * sync_single_*, to see if the memory was in fact allocated by this
67 static char *io_tlb_start
, *io_tlb_end
;
70 * The number of IO TLB blocks (in groups of 64) betweeen io_tlb_start and
71 * io_tlb_end. This is command line adjustable via setup_io_tlb_npages.
73 static unsigned long io_tlb_nslabs
;
76 * When the IOMMU overflows we return a fallback buffer. This sets the size.
78 static unsigned long io_tlb_overflow
= 32*1024;
80 void *io_tlb_overflow_buffer
;
83 * This is a free list describing the number of free entries available from
86 static unsigned int *io_tlb_list
;
87 static unsigned int io_tlb_index
;
90 * We need to save away the original address corresponding to a mapped entry
91 * for the sync operations.
93 static phys_addr_t
*io_tlb_orig_addr
;
96 * Protect the above data structures in the map and unmap calls
98 static DEFINE_SPINLOCK(io_tlb_lock
);
101 setup_io_tlb_npages(char *str
)
104 io_tlb_nslabs
= simple_strtoul(str
, &str
, 0);
105 /* avoid tail segment of size < IO_TLB_SEGSIZE */
106 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
110 if (!strcmp(str
, "force"))
114 __setup("swiotlb=", setup_io_tlb_npages
);
115 /* make io_tlb_overflow tunable too? */
117 /* Note that this doesn't work with highmem page */
118 static dma_addr_t
swiotlb_virt_to_bus(struct device
*hwdev
,
119 volatile void *address
)
121 return phys_to_dma(hwdev
, virt_to_phys(address
));
124 static void swiotlb_print_info(unsigned long bytes
)
126 phys_addr_t pstart
, pend
;
128 pstart
= virt_to_phys(io_tlb_start
);
129 pend
= virt_to_phys(io_tlb_end
);
131 printk(KERN_INFO
"Placing %luMB software IO TLB between %p - %p\n",
132 bytes
>> 20, io_tlb_start
, io_tlb_end
);
133 printk(KERN_INFO
"software IO TLB at phys %#llx - %#llx\n",
134 (unsigned long long)pstart
,
135 (unsigned long long)pend
);
139 * Statically reserve bounce buffer space and initialize bounce buffer data
140 * structures for the software IO TLB used to implement the DMA API.
143 swiotlb_init_with_default_size(size_t default_size
)
145 unsigned long i
, bytes
;
147 if (!io_tlb_nslabs
) {
148 io_tlb_nslabs
= (default_size
>> IO_TLB_SHIFT
);
149 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
152 bytes
= io_tlb_nslabs
<< IO_TLB_SHIFT
;
155 * Get IO TLB memory from the low pages
157 io_tlb_start
= alloc_bootmem_low_pages(bytes
);
159 panic("Cannot allocate SWIOTLB buffer");
160 io_tlb_end
= io_tlb_start
+ bytes
;
163 * Allocate and initialize the free list array. This array is used
164 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
165 * between io_tlb_start and io_tlb_end.
167 io_tlb_list
= alloc_bootmem(io_tlb_nslabs
* sizeof(int));
168 for (i
= 0; i
< io_tlb_nslabs
; i
++)
169 io_tlb_list
[i
] = IO_TLB_SEGSIZE
- OFFSET(i
, IO_TLB_SEGSIZE
);
171 io_tlb_orig_addr
= alloc_bootmem(io_tlb_nslabs
* sizeof(phys_addr_t
));
174 * Get the overflow emergency buffer
176 io_tlb_overflow_buffer
= alloc_bootmem_low(io_tlb_overflow
);
177 if (!io_tlb_overflow_buffer
)
178 panic("Cannot allocate SWIOTLB overflow buffer!\n");
180 swiotlb_print_info(bytes
);
186 swiotlb_init_with_default_size(64 * (1<<20)); /* default to 64MB */
190 * Systems with larger DMA zones (those that don't support ISA) can
191 * initialize the swiotlb later using the slab allocator if needed.
192 * This should be just like above, but with some error catching.
195 swiotlb_late_init_with_default_size(size_t default_size
)
197 unsigned long i
, bytes
, req_nslabs
= io_tlb_nslabs
;
200 if (!io_tlb_nslabs
) {
201 io_tlb_nslabs
= (default_size
>> IO_TLB_SHIFT
);
202 io_tlb_nslabs
= ALIGN(io_tlb_nslabs
, IO_TLB_SEGSIZE
);
206 * Get IO TLB memory from the low pages
208 order
= get_order(io_tlb_nslabs
<< IO_TLB_SHIFT
);
209 io_tlb_nslabs
= SLABS_PER_PAGE
<< order
;
210 bytes
= io_tlb_nslabs
<< IO_TLB_SHIFT
;
212 while ((SLABS_PER_PAGE
<< order
) > IO_TLB_MIN_SLABS
) {
213 io_tlb_start
= (void *)__get_free_pages(GFP_DMA
| __GFP_NOWARN
,
223 if (order
!= get_order(bytes
)) {
224 printk(KERN_WARNING
"Warning: only able to allocate %ld MB "
225 "for software IO TLB\n", (PAGE_SIZE
<< order
) >> 20);
226 io_tlb_nslabs
= SLABS_PER_PAGE
<< order
;
227 bytes
= io_tlb_nslabs
<< IO_TLB_SHIFT
;
229 io_tlb_end
= io_tlb_start
+ bytes
;
230 memset(io_tlb_start
, 0, bytes
);
233 * Allocate and initialize the free list array. This array is used
234 * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
235 * between io_tlb_start and io_tlb_end.
237 io_tlb_list
= (unsigned int *)__get_free_pages(GFP_KERNEL
,
238 get_order(io_tlb_nslabs
* sizeof(int)));
242 for (i
= 0; i
< io_tlb_nslabs
; i
++)
243 io_tlb_list
[i
] = IO_TLB_SEGSIZE
- OFFSET(i
, IO_TLB_SEGSIZE
);
246 io_tlb_orig_addr
= (phys_addr_t
*)
247 __get_free_pages(GFP_KERNEL
,
248 get_order(io_tlb_nslabs
*
249 sizeof(phys_addr_t
)));
250 if (!io_tlb_orig_addr
)
253 memset(io_tlb_orig_addr
, 0, io_tlb_nslabs
* sizeof(phys_addr_t
));
256 * Get the overflow emergency buffer
258 io_tlb_overflow_buffer
= (void *)__get_free_pages(GFP_DMA
,
259 get_order(io_tlb_overflow
));
260 if (!io_tlb_overflow_buffer
)
263 swiotlb_print_info(bytes
);
268 free_pages((unsigned long)io_tlb_orig_addr
,
269 get_order(io_tlb_nslabs
* sizeof(phys_addr_t
)));
270 io_tlb_orig_addr
= NULL
;
272 free_pages((unsigned long)io_tlb_list
, get_order(io_tlb_nslabs
*
277 free_pages((unsigned long)io_tlb_start
, order
);
280 io_tlb_nslabs
= req_nslabs
;
284 static int is_swiotlb_buffer(phys_addr_t paddr
)
286 return paddr
>= virt_to_phys(io_tlb_start
) &&
287 paddr
< virt_to_phys(io_tlb_end
);
291 * Bounce: copy the swiotlb buffer back to the original dma location
293 static void swiotlb_bounce(phys_addr_t phys
, char *dma_addr
, size_t size
,
294 enum dma_data_direction dir
)
296 unsigned long pfn
= PFN_DOWN(phys
);
298 if (PageHighMem(pfn_to_page(pfn
))) {
299 /* The buffer does not have a mapping. Map it in and copy */
300 unsigned int offset
= phys
& ~PAGE_MASK
;
306 sz
= min_t(size_t, PAGE_SIZE
- offset
, size
);
308 local_irq_save(flags
);
309 buffer
= kmap_atomic(pfn_to_page(pfn
),
311 if (dir
== DMA_TO_DEVICE
)
312 memcpy(dma_addr
, buffer
+ offset
, sz
);
314 memcpy(buffer
+ offset
, dma_addr
, sz
);
315 kunmap_atomic(buffer
, KM_BOUNCE_READ
);
316 local_irq_restore(flags
);
324 if (dir
== DMA_TO_DEVICE
)
325 memcpy(dma_addr
, phys_to_virt(phys
), size
);
327 memcpy(phys_to_virt(phys
), dma_addr
, size
);
332 * Allocates bounce buffer and returns its kernel virtual address.
335 map_single(struct device
*hwdev
, phys_addr_t phys
, size_t size
, int dir
)
339 unsigned int nslots
, stride
, index
, wrap
;
341 unsigned long start_dma_addr
;
343 unsigned long offset_slots
;
344 unsigned long max_slots
;
346 mask
= dma_get_seg_boundary(hwdev
);
347 start_dma_addr
= swiotlb_virt_to_bus(hwdev
, io_tlb_start
) & mask
;
349 offset_slots
= ALIGN(start_dma_addr
, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
;
352 * Carefully handle integer overflow which can occur when mask == ~0UL.
355 ? ALIGN(mask
+ 1, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
356 : 1UL << (BITS_PER_LONG
- IO_TLB_SHIFT
);
359 * For mappings greater than a page, we limit the stride (and
360 * hence alignment) to a page size.
362 nslots
= ALIGN(size
, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
;
363 if (size
> PAGE_SIZE
)
364 stride
= (1 << (PAGE_SHIFT
- IO_TLB_SHIFT
));
371 * Find suitable number of IO TLB entries size that will fit this
372 * request and allocate a buffer from that IO TLB pool.
374 spin_lock_irqsave(&io_tlb_lock
, flags
);
375 index
= ALIGN(io_tlb_index
, stride
);
376 if (index
>= io_tlb_nslabs
)
381 while (iommu_is_span_boundary(index
, nslots
, offset_slots
,
384 if (index
>= io_tlb_nslabs
)
391 * If we find a slot that indicates we have 'nslots' number of
392 * contiguous buffers, we allocate the buffers from that slot
393 * and mark the entries as '0' indicating unavailable.
395 if (io_tlb_list
[index
] >= nslots
) {
398 for (i
= index
; i
< (int) (index
+ nslots
); i
++)
400 for (i
= index
- 1; (OFFSET(i
, IO_TLB_SEGSIZE
) != IO_TLB_SEGSIZE
- 1) && io_tlb_list
[i
]; i
--)
401 io_tlb_list
[i
] = ++count
;
402 dma_addr
= io_tlb_start
+ (index
<< IO_TLB_SHIFT
);
405 * Update the indices to avoid searching in the next
408 io_tlb_index
= ((index
+ nslots
) < io_tlb_nslabs
409 ? (index
+ nslots
) : 0);
414 if (index
>= io_tlb_nslabs
)
416 } while (index
!= wrap
);
419 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
422 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
425 * Save away the mapping from the original address to the DMA address.
426 * This is needed when we sync the memory. Then we sync the buffer if
429 for (i
= 0; i
< nslots
; i
++)
430 io_tlb_orig_addr
[index
+i
] = phys
+ (i
<< IO_TLB_SHIFT
);
431 if (dir
== DMA_TO_DEVICE
|| dir
== DMA_BIDIRECTIONAL
)
432 swiotlb_bounce(phys
, dma_addr
, size
, DMA_TO_DEVICE
);
438 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
441 do_unmap_single(struct device
*hwdev
, char *dma_addr
, size_t size
, int dir
)
444 int i
, count
, nslots
= ALIGN(size
, 1 << IO_TLB_SHIFT
) >> IO_TLB_SHIFT
;
445 int index
= (dma_addr
- io_tlb_start
) >> IO_TLB_SHIFT
;
446 phys_addr_t phys
= io_tlb_orig_addr
[index
];
449 * First, sync the memory before unmapping the entry
451 if (phys
&& ((dir
== DMA_FROM_DEVICE
) || (dir
== DMA_BIDIRECTIONAL
)))
452 swiotlb_bounce(phys
, dma_addr
, size
, DMA_FROM_DEVICE
);
455 * Return the buffer to the free list by setting the corresponding
456 * entries to indicate the number of contigous entries available.
457 * While returning the entries to the free list, we merge the entries
458 * with slots below and above the pool being returned.
460 spin_lock_irqsave(&io_tlb_lock
, flags
);
462 count
= ((index
+ nslots
) < ALIGN(index
+ 1, IO_TLB_SEGSIZE
) ?
463 io_tlb_list
[index
+ nslots
] : 0);
465 * Step 1: return the slots to the free list, merging the
466 * slots with superceeding slots
468 for (i
= index
+ nslots
- 1; i
>= index
; i
--)
469 io_tlb_list
[i
] = ++count
;
471 * Step 2: merge the returned slots with the preceding slots,
472 * if available (non zero)
474 for (i
= index
- 1; (OFFSET(i
, IO_TLB_SEGSIZE
) != IO_TLB_SEGSIZE
-1) && io_tlb_list
[i
]; i
--)
475 io_tlb_list
[i
] = ++count
;
477 spin_unlock_irqrestore(&io_tlb_lock
, flags
);
481 sync_single(struct device
*hwdev
, char *dma_addr
, size_t size
,
484 int index
= (dma_addr
- io_tlb_start
) >> IO_TLB_SHIFT
;
485 phys_addr_t phys
= io_tlb_orig_addr
[index
];
487 phys
+= ((unsigned long)dma_addr
& ((1 << IO_TLB_SHIFT
) - 1));
491 if (likely(dir
== DMA_FROM_DEVICE
|| dir
== DMA_BIDIRECTIONAL
))
492 swiotlb_bounce(phys
, dma_addr
, size
, DMA_FROM_DEVICE
);
494 BUG_ON(dir
!= DMA_TO_DEVICE
);
496 case SYNC_FOR_DEVICE
:
497 if (likely(dir
== DMA_TO_DEVICE
|| dir
== DMA_BIDIRECTIONAL
))
498 swiotlb_bounce(phys
, dma_addr
, size
, DMA_TO_DEVICE
);
500 BUG_ON(dir
!= DMA_FROM_DEVICE
);
508 swiotlb_alloc_coherent(struct device
*hwdev
, size_t size
,
509 dma_addr_t
*dma_handle
, gfp_t flags
)
513 int order
= get_order(size
);
514 u64 dma_mask
= DMA_BIT_MASK(32);
516 if (hwdev
&& hwdev
->coherent_dma_mask
)
517 dma_mask
= hwdev
->coherent_dma_mask
;
519 ret
= (void *)__get_free_pages(flags
, order
);
520 if (ret
&& swiotlb_virt_to_bus(hwdev
, ret
) + size
> dma_mask
) {
522 * The allocated memory isn't reachable by the device.
524 free_pages((unsigned long) ret
, order
);
529 * We are either out of memory or the device can't DMA
530 * to GFP_DMA memory; fall back on map_single(), which
531 * will grab memory from the lowest available address range.
533 ret
= map_single(hwdev
, 0, size
, DMA_FROM_DEVICE
);
538 memset(ret
, 0, size
);
539 dev_addr
= swiotlb_virt_to_bus(hwdev
, ret
);
541 /* Confirm address can be DMA'd by device */
542 if (dev_addr
+ size
> dma_mask
) {
543 printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
544 (unsigned long long)dma_mask
,
545 (unsigned long long)dev_addr
);
547 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
548 do_unmap_single(hwdev
, ret
, size
, DMA_TO_DEVICE
);
551 *dma_handle
= dev_addr
;
554 EXPORT_SYMBOL(swiotlb_alloc_coherent
);
557 swiotlb_free_coherent(struct device
*hwdev
, size_t size
, void *vaddr
,
560 phys_addr_t paddr
= dma_to_phys(hwdev
, dev_addr
);
562 WARN_ON(irqs_disabled());
563 if (!is_swiotlb_buffer(paddr
))
564 free_pages((unsigned long)vaddr
, get_order(size
));
566 /* DMA_TO_DEVICE to avoid memcpy in unmap_single */
567 do_unmap_single(hwdev
, vaddr
, size
, DMA_TO_DEVICE
);
569 EXPORT_SYMBOL(swiotlb_free_coherent
);
572 swiotlb_full(struct device
*dev
, size_t size
, int dir
, int do_panic
)
575 * Ran out of IOMMU space for this operation. This is very bad.
576 * Unfortunately the drivers cannot handle this operation properly.
577 * unless they check for dma_mapping_error (most don't)
578 * When the mapping is small enough return a static buffer to limit
579 * the damage, or panic when the transfer is too big.
581 printk(KERN_ERR
"DMA: Out of SW-IOMMU space for %zu bytes at "
582 "device %s\n", size
, dev
? dev_name(dev
) : "?");
584 if (size
<= io_tlb_overflow
|| !do_panic
)
587 if (dir
== DMA_BIDIRECTIONAL
)
588 panic("DMA: Random memory could be DMA accessed\n");
589 if (dir
== DMA_FROM_DEVICE
)
590 panic("DMA: Random memory could be DMA written\n");
591 if (dir
== DMA_TO_DEVICE
)
592 panic("DMA: Random memory could be DMA read\n");
596 * Map a single buffer of the indicated size for DMA in streaming mode. The
597 * physical address to use is returned.
599 * Once the device is given the dma address, the device owns this memory until
600 * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
602 dma_addr_t
swiotlb_map_page(struct device
*dev
, struct page
*page
,
603 unsigned long offset
, size_t size
,
604 enum dma_data_direction dir
,
605 struct dma_attrs
*attrs
)
607 phys_addr_t phys
= page_to_phys(page
) + offset
;
608 dma_addr_t dev_addr
= phys_to_dma(dev
, phys
);
611 BUG_ON(dir
== DMA_NONE
);
613 * If the address happens to be in the device's DMA window,
614 * we can safely return the device addr and not worry about bounce
617 if (dma_capable(dev
, dev_addr
, size
) && !swiotlb_force
)
621 * Oh well, have to allocate and map a bounce buffer.
623 map
= map_single(dev
, phys
, size
, dir
);
625 swiotlb_full(dev
, size
, dir
, 1);
626 map
= io_tlb_overflow_buffer
;
629 dev_addr
= swiotlb_virt_to_bus(dev
, map
);
632 * Ensure that the address returned is DMA'ble
634 if (!dma_capable(dev
, dev_addr
, size
))
635 panic("map_single: bounce buffer is not DMA'ble");
639 EXPORT_SYMBOL_GPL(swiotlb_map_page
);
642 * Unmap a single streaming mode DMA translation. The dma_addr and size must
643 * match what was provided for in a previous swiotlb_map_page call. All
644 * other usages are undefined.
646 * After this call, reads by the cpu to the buffer are guaranteed to see
647 * whatever the device wrote there.
649 static void unmap_single(struct device
*hwdev
, dma_addr_t dev_addr
,
650 size_t size
, int dir
)
652 phys_addr_t paddr
= dma_to_phys(hwdev
, dev_addr
);
654 BUG_ON(dir
== DMA_NONE
);
656 if (is_swiotlb_buffer(paddr
)) {
657 do_unmap_single(hwdev
, phys_to_virt(paddr
), size
, dir
);
661 if (dir
!= DMA_FROM_DEVICE
)
665 * phys_to_virt doesn't work with hihgmem page but we could
666 * call dma_mark_clean() with hihgmem page here. However, we
667 * are fine since dma_mark_clean() is null on POWERPC. We can
668 * make dma_mark_clean() take a physical address if necessary.
670 dma_mark_clean(phys_to_virt(paddr
), size
);
673 void swiotlb_unmap_page(struct device
*hwdev
, dma_addr_t dev_addr
,
674 size_t size
, enum dma_data_direction dir
,
675 struct dma_attrs
*attrs
)
677 unmap_single(hwdev
, dev_addr
, size
, dir
);
679 EXPORT_SYMBOL_GPL(swiotlb_unmap_page
);
682 * Make physical memory consistent for a single streaming mode DMA translation
685 * If you perform a swiotlb_map_page() but wish to interrogate the buffer
686 * using the cpu, yet do not wish to teardown the dma mapping, you must
687 * call this function before doing so. At the next point you give the dma
688 * address back to the card, you must first perform a
689 * swiotlb_dma_sync_for_device, and then the device again owns the buffer
692 swiotlb_sync_single(struct device
*hwdev
, dma_addr_t dev_addr
,
693 size_t size
, int dir
, int target
)
695 phys_addr_t paddr
= dma_to_phys(hwdev
, dev_addr
);
697 BUG_ON(dir
== DMA_NONE
);
699 if (is_swiotlb_buffer(paddr
)) {
700 sync_single(hwdev
, phys_to_virt(paddr
), size
, dir
, target
);
704 if (dir
!= DMA_FROM_DEVICE
)
707 dma_mark_clean(phys_to_virt(paddr
), size
);
711 swiotlb_sync_single_for_cpu(struct device
*hwdev
, dma_addr_t dev_addr
,
712 size_t size
, enum dma_data_direction dir
)
714 swiotlb_sync_single(hwdev
, dev_addr
, size
, dir
, SYNC_FOR_CPU
);
716 EXPORT_SYMBOL(swiotlb_sync_single_for_cpu
);
719 swiotlb_sync_single_for_device(struct device
*hwdev
, dma_addr_t dev_addr
,
720 size_t size
, enum dma_data_direction dir
)
722 swiotlb_sync_single(hwdev
, dev_addr
, size
, dir
, SYNC_FOR_DEVICE
);
724 EXPORT_SYMBOL(swiotlb_sync_single_for_device
);
727 * Same as above, but for a sub-range of the mapping.
730 swiotlb_sync_single_range(struct device
*hwdev
, dma_addr_t dev_addr
,
731 unsigned long offset
, size_t size
,
734 swiotlb_sync_single(hwdev
, dev_addr
+ offset
, size
, dir
, target
);
738 swiotlb_sync_single_range_for_cpu(struct device
*hwdev
, dma_addr_t dev_addr
,
739 unsigned long offset
, size_t size
,
740 enum dma_data_direction dir
)
742 swiotlb_sync_single_range(hwdev
, dev_addr
, offset
, size
, dir
,
745 EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_cpu
);
748 swiotlb_sync_single_range_for_device(struct device
*hwdev
, dma_addr_t dev_addr
,
749 unsigned long offset
, size_t size
,
750 enum dma_data_direction dir
)
752 swiotlb_sync_single_range(hwdev
, dev_addr
, offset
, size
, dir
,
755 EXPORT_SYMBOL_GPL(swiotlb_sync_single_range_for_device
);
758 * Map a set of buffers described by scatterlist in streaming mode for DMA.
759 * This is the scatter-gather version of the above swiotlb_map_page
760 * interface. Here the scatter gather list elements are each tagged with the
761 * appropriate dma address and length. They are obtained via
762 * sg_dma_{address,length}(SG).
764 * NOTE: An implementation may be able to use a smaller number of
765 * DMA address/length pairs than there are SG table elements.
766 * (for example via virtual mapping capabilities)
767 * The routine returns the number of addr/length pairs actually
768 * used, at most nents.
770 * Device ownership issues as mentioned above for swiotlb_map_page are the
774 swiotlb_map_sg_attrs(struct device
*hwdev
, struct scatterlist
*sgl
, int nelems
,
775 enum dma_data_direction dir
, struct dma_attrs
*attrs
)
777 struct scatterlist
*sg
;
780 BUG_ON(dir
== DMA_NONE
);
782 for_each_sg(sgl
, sg
, nelems
, i
) {
783 phys_addr_t paddr
= sg_phys(sg
);
784 dma_addr_t dev_addr
= phys_to_dma(hwdev
, paddr
);
787 !dma_capable(hwdev
, dev_addr
, sg
->length
)) {
788 void *map
= map_single(hwdev
, sg_phys(sg
),
791 /* Don't panic here, we expect map_sg users
792 to do proper error handling. */
793 swiotlb_full(hwdev
, sg
->length
, dir
, 0);
794 swiotlb_unmap_sg_attrs(hwdev
, sgl
, i
, dir
,
796 sgl
[0].dma_length
= 0;
799 sg
->dma_address
= swiotlb_virt_to_bus(hwdev
, map
);
801 sg
->dma_address
= dev_addr
;
802 sg
->dma_length
= sg
->length
;
806 EXPORT_SYMBOL(swiotlb_map_sg_attrs
);
809 swiotlb_map_sg(struct device
*hwdev
, struct scatterlist
*sgl
, int nelems
,
812 return swiotlb_map_sg_attrs(hwdev
, sgl
, nelems
, dir
, NULL
);
814 EXPORT_SYMBOL(swiotlb_map_sg
);
817 * Unmap a set of streaming mode DMA translations. Again, cpu read rules
818 * concerning calls here are the same as for swiotlb_unmap_page() above.
821 swiotlb_unmap_sg_attrs(struct device
*hwdev
, struct scatterlist
*sgl
,
822 int nelems
, enum dma_data_direction dir
, struct dma_attrs
*attrs
)
824 struct scatterlist
*sg
;
827 BUG_ON(dir
== DMA_NONE
);
829 for_each_sg(sgl
, sg
, nelems
, i
)
830 unmap_single(hwdev
, sg
->dma_address
, sg
->dma_length
, dir
);
833 EXPORT_SYMBOL(swiotlb_unmap_sg_attrs
);
836 swiotlb_unmap_sg(struct device
*hwdev
, struct scatterlist
*sgl
, int nelems
,
839 return swiotlb_unmap_sg_attrs(hwdev
, sgl
, nelems
, dir
, NULL
);
841 EXPORT_SYMBOL(swiotlb_unmap_sg
);
844 * Make physical memory consistent for a set of streaming mode DMA translations
847 * The same as swiotlb_sync_single_* but for a scatter-gather list, same rules
851 swiotlb_sync_sg(struct device
*hwdev
, struct scatterlist
*sgl
,
852 int nelems
, int dir
, int target
)
854 struct scatterlist
*sg
;
857 for_each_sg(sgl
, sg
, nelems
, i
)
858 swiotlb_sync_single(hwdev
, sg
->dma_address
,
859 sg
->dma_length
, dir
, target
);
863 swiotlb_sync_sg_for_cpu(struct device
*hwdev
, struct scatterlist
*sg
,
864 int nelems
, enum dma_data_direction dir
)
866 swiotlb_sync_sg(hwdev
, sg
, nelems
, dir
, SYNC_FOR_CPU
);
868 EXPORT_SYMBOL(swiotlb_sync_sg_for_cpu
);
871 swiotlb_sync_sg_for_device(struct device
*hwdev
, struct scatterlist
*sg
,
872 int nelems
, enum dma_data_direction dir
)
874 swiotlb_sync_sg(hwdev
, sg
, nelems
, dir
, SYNC_FOR_DEVICE
);
876 EXPORT_SYMBOL(swiotlb_sync_sg_for_device
);
879 swiotlb_dma_mapping_error(struct device
*hwdev
, dma_addr_t dma_addr
)
881 return (dma_addr
== swiotlb_virt_to_bus(hwdev
, io_tlb_overflow_buffer
));
883 EXPORT_SYMBOL(swiotlb_dma_mapping_error
);
886 * Return whether the given device DMA address mask can be supported
887 * properly. For example, if your device can only drive the low 24-bits
888 * during bus mastering, then you would pass 0x00ffffff as the mask to
892 swiotlb_dma_supported(struct device
*hwdev
, u64 mask
)
894 return swiotlb_virt_to_bus(hwdev
, io_tlb_end
- 1) <= mask
;
896 EXPORT_SYMBOL(swiotlb_dma_supported
);