Release 4.9 lib/swiotlb.c

/*
 * Dynamic DMA mapping support.
 *
 * This implementation is a fallback for platforms that do not support
 * I/O TLBs (aka DMA address translation hardware).
 * Copyright (C) 2000 Asit Mallick <Asit.K.Mallick@intel.com>
 * Copyright (C) 2000 Goutham Rao <goutham.rao@intel.com>
 * Copyright (C) 2000, 2003 Hewlett-Packard Co
 *      David Mosberger-Tang <davidm@hpl.hp.com>
 *
 * 03/05/07 davidm      Switch from PCI-DMA to generic device DMA API.
 * 00/12/13 davidm      Rename to swiotlb.c and add mark_clean() to avoid
 *                      unnecessary i-cache flushing.
 * 04/07/.. ak          Better overflow handling. Assorted fixes.
 * 05/09/10 linville    Add support for syncing ranges, support syncing for
 *                      DMA_BIDIRECTIONAL mappings, miscellaneous cleanup.
 * 08/12/11 beckyb      Add highmem support
 */

#include <linux/cache.h>
#include <linux/dma-mapping.h>
#include <linux/mm.h>
#include <linux/export.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/swiotlb.h>
#include <linux/pfn.h>
#include <linux/types.h>
#include <linux/ctype.h>
#include <linux/highmem.h>
#include <linux/gfp.h>
#include <linux/scatterlist.h>

#include <asm/io.h>
#include <asm/dma.h>

#include <linux/init.h>
#include <linux/bootmem.h>
#include <linux/iommu-helper.h>


#define CREATE_TRACE_POINTS
#include <trace/events/swiotlb.h>


#define OFFSET(val,align) ((unsigned long)        \
                           ( (val) & ( (align) - 1)))


#define SLABS_PER_PAGE (1 << (PAGE_SHIFT - IO_TLB_SHIFT))

/*
 * Minimum IO TLB size to bother booting with.  Systems with mainly
 * 64bit capable cards will only lightly use the swiotlb.  If we can't
 * allocate a contiguous 1MB, we're probably in trouble anyway.
 */

#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)


int swiotlb_force;

/*
 * Used to do a quick range check in swiotlb_tbl_unmap_single and
 * swiotlb_tbl_sync_single_*, to see if the memory was in fact allocated by this
 * API.
 */


static phys_addr_t io_tlb_start, io_tlb_end;

/*
 * The number of IO TLB blocks (in groups of 64) between io_tlb_start and
 * io_tlb_end.  This is command line adjustable via setup_io_tlb_npages.
 */

static unsigned long io_tlb_nslabs;

/*
 * When the IOMMU overflows we return a fallback buffer. This sets the size.
 */

static unsigned long io_tlb_overflow = 32*1024;


static phys_addr_t io_tlb_overflow_buffer;

/*
 * This is a free list describing the number of free entries available from
 * each index
 */

static unsigned int *io_tlb_list;

static unsigned int io_tlb_index;

/*
 * We need to save away the original address corresponding to a mapped entry
 * for the sync operations.
 */

#define INVALID_PHYS_ADDR (~(phys_addr_t)0)

static phys_addr_t *io_tlb_orig_addr;

/*
 * Protect the above data structures in the map and unmap calls
 */
static DEFINE_SPINLOCK(io_tlb_lock);


static int late_alloc;


static int __init

setup_io_tlb_npages(char *str)
{
	if (isdigit(*str)) {
		io_tlb_nslabs = simple_strtoul(str, &str, 0);
		/* avoid tail segment of size < IO_TLB_SEGSIZE */
		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
	}
	if (*str == ',')
		++str;
	if (!strcmp(str, "force"))
		swiotlb_force = 1;

	return 0;
}
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david mosberger
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14.29%
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yinghai lu
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4
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early_param("swiotlb", setup_io_tlb_npages);
/* make io_tlb_overflow tunable too? */



unsigned long swiotlb_nr_tbl(void)
{
	return io_tlb_nslabs;
}
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EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);

/* default to 64MB */

#define IO_TLB_DEFAULT_SIZE (64UL<<20)


unsigned long swiotlb_size_or_default(void)
{
	unsigned long size;

	size = io_tlb_nslabs << IO_TLB_SHIFT;

	return size ? size : (IO_TLB_DEFAULT_SIZE);
}

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/* Note that this doesn't work with highmem page */


static dma_addr_t swiotlb_virt_to_bus(struct device *hwdev,
				      volatile void *address)
{
	return phys_to_dma(hwdev, virt_to_phys(address));
}

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jeremy fitzhardinge
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fujita tomonori
fujita tomonori
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static bool no_iotlb_memory;



void swiotlb_print_info(void)
{
	unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
	unsigned char *vstart, *vend;

	if (no_iotlb_memory) {
		pr_warn("software IO TLB: No low mem\n");
		return;
	}

	vstart = phys_to_virt(io_tlb_start);
	vend = phys_to_virt(io_tlb_end);

	printk(KERN_INFO "software IO TLB [mem %#010llx-%#010llx] (%luMB) mapped at [%p-%p]\n",
	       (unsigned long long)io_tlb_start,
	       (unsigned long long)io_tlb_end,
	       bytes >> 20, vstart, vend - 1);
}

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yinghai lu
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bjorn helgaas
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fujita tomonori
fujita tomonori
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int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
{
	void *v_overflow_buffer;
	unsigned long i, bytes;

	bytes = nslabs << IO_TLB_SHIFT;

	io_tlb_nslabs = nslabs;
	io_tlb_start = __pa(tlb);
	io_tlb_end = io_tlb_start + bytes;

	/*
         * Get the overflow emergency buffer
         */
	v_overflow_buffer = memblock_virt_alloc_low_nopanic(
						PAGE_ALIGN(io_tlb_overflow),
						PAGE_SIZE);
	if (!v_overflow_buffer)
		return -ENOMEM;

	io_tlb_overflow_buffer = __pa(v_overflow_buffer);

	/*
         * Allocate and initialize the free list array.  This array is used
         * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
         * between io_tlb_start and io_tlb_end.
         */
	io_tlb_list = memblock_virt_alloc(
				PAGE_ALIGN(io_tlb_nslabs * sizeof(int)),
				PAGE_SIZE);
	io_tlb_orig_addr = memblock_virt_alloc(
				PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)),
				PAGE_SIZE);
	for (i = 0; i < io_tlb_nslabs; i++) {
		io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
	}
	io_tlb_index = 0;

	if (verbose)
		swiotlb_print_info();

	return 0;
}

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alexander duyck
alexander duyck
29
17.68%
2
13.33%
fujita tomonori
fujita tomonori
21
12.80%
2
13.33%
yinghai lu
yinghai lu
12
7.32%
3
20.00%
david mosberger
david mosberger
9
5.49%
2
13.33%
santosh shilimkar
santosh shilimkar
5
3.05%
1
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andi kleen
andi kleen
2
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ian campbell
ian campbell
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/*
 * Statically reserve bounce buffer space and initialize bounce buffer data
 * structures for the software IO TLB used to implement the DMA API.
 */

void  __init

swiotlb_init(int verbose)
{
	size_t default_size = IO_TLB_DEFAULT_SIZE;
	unsigned char *vstart;
	unsigned long bytes;

	if (!io_tlb_nslabs) {
		io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
	}

	bytes = io_tlb_nslabs << IO_TLB_SHIFT;

	/* Get IO TLB memory from the low pages */
	vstart = memblock_virt_alloc_low_nopanic(PAGE_ALIGN(bytes), PAGE_SIZE);
	if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))
		return;

	if (io_tlb_start)
		memblock_free_early(io_tlb_start,
				    PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
	pr_warn("Cannot allocate SWIOTLB buffer");
	no_iotlb_memory = true;
}

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alexander duyck
alexander duyck
8
7.55%
1
11.11%
david mosberger
david mosberger
4
3.77%
1
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santosh shilimkar
santosh shilimkar
3
2.83%
1
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106
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9
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/*
 * Systems with larger DMA zones (those that don't support ISA) can
 * initialize the swiotlb later using the slab allocator if needed.
 * This should be just like above, but with some error catching.
 */

int

swiotlb_late_init_with_default_size(size_t default_size)
{
	unsigned long bytes, req_nslabs = io_tlb_nslabs;
	unsigned char *vstart = NULL;
	unsigned int order;
	int rc = 0;

	if (!io_tlb_nslabs) {
		io_tlb_nslabs = (default_size >> IO_TLB_SHIFT);
		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
	}

	/*
         * Get IO TLB memory from the low pages
         */
	order = get_order(io_tlb_nslabs << IO_TLB_SHIFT);
	io_tlb_nslabs = SLABS_PER_PAGE << order;
	bytes = io_tlb_nslabs << IO_TLB_SHIFT;

	while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
		vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
						  order);
		if (vstart)
			break;
		order--;
	}

	if (!vstart) {
		io_tlb_nslabs = req_nslabs;
		return -ENOMEM;
	}
	if (order != get_order(bytes)) {
		printk(KERN_WARNING "Warning: only able to allocate %ld MB "
		       "for software IO TLB\n", (PAGE_SIZE << order) >> 20);
		io_tlb_nslabs = SLABS_PER_PAGE << order;
	}
	rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);
	if (rc)
		free_pages((unsigned long)vstart, order);
	return rc;
}

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konrad rzeszutek wilk
40
21.39%
1
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alexander duyck
alexander duyck
12
6.42%
1
16.67%
jan beulich
jan beulich
11
5.88%
1
16.67%
fujita tomonori
fujita tomonori
9
4.81%
1
16.67%
jeremy fitzhardinge
jeremy fitzhardinge
1
0.53%
1
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187
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6
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int

swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
	unsigned long i, bytes;
	unsigned char *v_overflow_buffer;

	bytes = nslabs << IO_TLB_SHIFT;

	io_tlb_nslabs = nslabs;
	io_tlb_start = virt_to_phys(tlb);
	io_tlb_end = io_tlb_start + bytes;

	memset(tlb, 0, bytes);

	/*
         * Get the overflow emergency buffer
         */
	v_overflow_buffer = (void *)__get_free_pages(GFP_DMA,
						     get_order(io_tlb_overflow));
	if (!v_overflow_buffer)
		goto cleanup2;

	io_tlb_overflow_buffer = virt_to_phys(v_overflow_buffer);

	/*
         * Allocate and initialize the free list array.  This array is used
         * to find contiguous free memory regions of size up to IO_TLB_SEGSIZE
         * between io_tlb_start and io_tlb_end.
         */
	io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
	                              get_order(io_tlb_nslabs * sizeof(int)));
	if (!io_tlb_list)
		goto cleanup3;

	io_tlb_orig_addr = (phys_addr_t *)
		__get_free_pages(GFP_KERNEL,
				 get_order(io_tlb_nslabs *
					   sizeof(phys_addr_t)));
	if (!io_tlb_orig_addr)
		goto cleanup4;

	for (i = 0; i < io_tlb_nslabs; i++) {
		io_tlb_list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
	}
	io_tlb_index = 0;

	swiotlb_print_info();

	late_alloc = 1;

	return 0;

cleanup4:
	free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
	                                                 sizeof(int)));
	io_tlb_list = NULL;
cleanup3:
	free_pages((unsigned long)v_overflow_buffer,
		   get_order(io_tlb_overflow));
	io_tlb_overflow_buffer = 0;
cleanup2:
	io_tlb_end = 0;
	io_tlb_start = 0;
	io_tlb_nslabs = 0;
	return -ENOMEM;
}

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alexander duyck
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3
27.27%
jan beulich
jan beulich
42
16.09%
2
18.18%
konrad rzeszutek wilk
konrad rzeszutek wilk
30
11.49%
1
9.09%
fujita tomonori
fujita tomonori
5
1.92%
2
18.18%
becky bruce
becky bruce
2
0.77%
1
9.09%
ian campbell
ian campbell
1
0.38%
1
9.09%
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261
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11
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void __init swiotlb_free(void)
{
	if (!io_tlb_orig_addr)
		return;

	if (late_alloc) {
		free_pages((unsigned long)phys_to_virt(io_tlb_overflow_buffer),
			   get_order(io_tlb_overflow));
		free_pages((unsigned long)io_tlb_orig_addr,
			   get_order(io_tlb_nslabs * sizeof(phys_addr_t)));
		free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
								 sizeof(int)));
		free_pages((unsigned long)phys_to_virt(io_tlb_start),
			   get_order(io_tlb_nslabs << IO_TLB_SHIFT));
	} else {
		memblock_free_late(io_tlb_overflow_buffer,
				   PAGE_ALIGN(io_tlb_overflow));
		memblock_free_late(__pa(io_tlb_orig_addr),
				   PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)));
		memblock_free_late(__pa(io_tlb_list),
				   PAGE_ALIGN(io_tlb_nslabs * sizeof(int)));
		memblock_free_late(io_tlb_start,
				   PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));
	}
	io_tlb_nslabs = 0;
}

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fujita tomonori
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yinghai lu
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7.55%
1
16.67%
alexander duyck
alexander duyck
7
4.40%
2
33.33%
konrad rzeszutek wilk
konrad rzeszutek wilk
4
2.52%
1
16.67%
santosh shilimkar
santosh shilimkar
4
2.52%
1
16.67%
Total
159
100.00%
6
100.00%



int is_swiotlb_buffer(phys_addr_t paddr)
{
	return paddr >= io_tlb_start && paddr < io_tlb_end;
}

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/*
 * Bounce: copy the swiotlb buffer back to the original dma location
 */


static void swiotlb_bounce(phys_addr_t orig_addr, phys_addr_t tlb_addr,
			   size_t size, enum dma_data_direction dir)
{
	unsigned long pfn = PFN_DOWN(orig_addr);
	unsigned char *vaddr = phys_to_virt(tlb_addr);

	if (PageHighMem(pfn_to_page(pfn))) {
		/* The buffer does not have a mapping.  Map it in and copy */
		unsigned int offset = orig_addr & ~PAGE_MASK;
		char *buffer;
		unsigned int sz = 0;
		unsigned long flags;

		while (size) {
			sz = min_t(size_t, PAGE_SIZE - offset, size);

			local_irq_save(flags);
			buffer = kmap_atomic(pfn_to_page(pfn));
			if (dir == DMA_TO_DEVICE)
				memcpy(vaddr, buffer + offset, sz);
			else
				memcpy(buffer + offset, vaddr, sz);
			kunmap_atomic(buffer);
			local_irq_restore(flags);

			size -= sz;
			pfn++;
			vaddr += sz;
			offset = 0;
		}
	} else if (dir == DMA_TO_DEVICE) {
		memcpy(vaddr, phys_to_virt(orig_addr), size);
	} else {
		memcpy(phys_to_virt(orig_addr), vaddr, size);
	}
}

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phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
				   dma_addr_t tbl_dma_addr,
				   phys_addr_t orig_addr, size_t size,
				   enum dma_data_direction dir)
{
	unsigned long flags;
	phys_addr_t tlb_addr;
	unsigned int nslots, stride, index, wrap;
	int i;
	unsigned long mask;
	unsigned long offset_slots;
	unsigned long max_slots;

	if (no_iotlb_memory)
		panic("Can not allocate SWIOTLB buffer earlier and can't now provide you with the DMA bounce buffer");

	mask = dma_get_seg_boundary(hwdev);

	tbl_dma_addr &= mask;

	offset_slots = ALIGN(tbl_dma_addr, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;

	/*
         * Carefully handle integer overflow which can occur when mask == ~0UL.
         */
	max_slots = mask + 1
		    ? ALIGN(mask + 1, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT
		    : 1UL << (BITS_PER_LONG - IO_TLB_SHIFT);

	/*
         * For mappings greater than a page, we limit the stride (and
         * hence alignment) to a page size.
         */
	nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
	if (size > PAGE_SIZE)
		stride = (1 << (PAGE_SHIFT - IO_TLB_SHIFT));
	else
		stride = 1;

	BUG_ON(!nslots);

	/*
         * Find suitable number of IO TLB entries size that will fit this
         * request and allocate a buffer from that IO TLB pool.
         */
	spin_lock_irqsave(&io_tlb_lock, flags);
	index = ALIGN(io_tlb_index, stride);
	if (index >= io_tlb_nslabs)
		index = 0;
	wrap = index;

	do {
		while (iommu_is_span_boundary(index, nslots, offset_slots,
					      max_slots)) {
			index += stride;
			if (index >= io_tlb_nslabs)
				index = 0;
			if (index == wrap)
				goto not_found;
		}

		/*
                 * If we find a slot that indicates we have 'nslots' number of
                 * contiguous buffers, we allocate the buffers from that slot
                 * and mark the entries as '0' indicating unavailable.
                 */
		if (io_tlb_list[index] >= nslots) {
			int count = 0;

			for (i = index; i < (int) (index + nslots); i++)
				io_tlb_list[i] = 0;
			for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && io_tlb_list[i]; i--)
				io_tlb_list[i] = ++count;
			tlb_addr = io_tlb_start + (index << IO_TLB_SHIFT);

			/*
                         * Update the indices to avoid searching in the next
                         * round.
                         */
			io_tlb_index = ((index + nslots) < io_tlb_nslabs
					? (index + nslots) : 0);

			goto found;
		}
		index += stride;
		if (index >= io_tlb_nslabs)
			index = 0;
	} while (index != wrap);

not_found:
	spin_unlock_irqrestore(&io_tlb_lock, flags);
	if (printk_ratelimit())
		dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
	return SWIOTLB_MAP_ERROR;
found:
	spin_unlock_irqrestore(&io_tlb_lock, flags);

	/*
         * Save away the mapping from the original address to the DMA address.
         * This is needed when we sync the memory.  Then we sync the buffer if
         * needed.
         */
	for (i = 0; i < nslots; i++)
		io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT);
	if (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL)
		swiotlb_bounce(orig_addr, tlb_addr, size, DMA_TO_DEVICE);

	return tlb_addr;
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
linus torvalds
linus torvalds
246
53.71%
1
4.35%
fujita tomonori
fujita tomonori
83
18.12%
3
13.04%
jan beulich
jan beulich
30
6.55%
2
8.70%
david mosberger
david mosberger
21
4.59%
2
8.70%
keir fraser
keir fraser
17
3.71%
1
4.35%
konrad rzeszutek wilk
konrad rzeszutek wilk
10
2.18%
2
8.70%
alexander duyck
alexander duyck
10
2.18%
1
4.35%
yinghai lu
yinghai lu
9
1.97%
1
4.35%
andi kleen
andi kleen
6
1.31%
1
4.35%
stefano stabellini
stefano stabellini
6
1.31%
1
4.35%
becky bruce
becky bruce
6
1.31%
2
8.70%
jesse barnes
jesse barnes
4
0.87%
1
4.35%
eric sesterhenn
eric sesterhenn
3
0.66%
1
4.35%
jeremy fitzhardinge
jeremy fitzhardinge
3
0.66%
1
4.35%
andrew morton
andrew morton
2
0.44%
1
4.35%
ian campbell
ian campbell
1
0.22%
1
4.35%
tony luck
tony luck
1
0.22%
1
4.35%
Total
458
100.00%
23
100.00%


EXPORT_SYMBOL_GPL(swiotlb_tbl_map_single);

/*
 * Allocates bounce buffer and returns its kernel virtual address.
 */


static phys_addr_t

map_single(struct device *hwdev, phys_addr_t phys, size_t size,
	   enum dma_data_direction dir)
{
	dma_addr_t start_dma_addr = phys_to_dma(hwdev, io_tlb_start);

	return swiotlb_tbl_map_single(hwdev, start_dma_addr, phys, size, dir);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
fujita tomonori
fujita tomonori
40
88.89%
1
20.00%
konrad rzeszutek wilk
konrad rzeszutek wilk
2
4.44%
1
20.00%
alexander duyck
alexander duyck
2
4.44%
2
40.00%
alexandre courbot
alexandre courbot
1
2.22%
1
20.00%
Total
45
100.00%
5
100.00%

/*
 * dma_addr is the kernel virtual address of the bounce buffer to unmap.
 */


void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
			      size_t size, enum dma_data_direction dir)
{
	unsigned long flags;
	int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT;
	int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
	phys_addr_t orig_addr = io_tlb_orig_addr[index];

	/*
         * First, sync the memory before unmapping the entry
         */
	if (orig_addr != INVALID_PHYS_ADDR &&
	    ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL)))
		swiotlb_bounce(orig_addr, tlb_addr, size, DMA_FROM_DEVICE);

	/*
         * Return the buffer to the free list by setting the corresponding
         * entries to indicate the number of contiguous entries available.
         * While returning the entries to the free list, we merge the entries
         * with slots below and above the pool being returned.
         */
	spin_lock_irqsave(&io_tlb_lock, flags);
	{
		count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
			 io_tlb_list[index + nslots] : 0);
		/*
                 * Step 1: return the slots to the free list, merging the
                 * slots with superceeding slots
                 */
		for (i = index + nslots - 1; i >= index; i--) {
			io_tlb_list[i] = ++count;
			io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
		}
		/*
                 * Step 2: merge the returned slots with the preceding slots,
                 * if available (non zero)
                 */
		for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && io_tlb_list[i]; i--)
			io_tlb_list[i] = ++count;
	}
	spin_unlock_irqrestore(&io_tlb_lock, flags);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
linus torvalds
linus torvalds
150
70.42%
1
7.69%
david mosberger
david mosberger
23
10.80%
2
15.38%
jan beulich
jan beulich
11
5.16%
1
7.69%
becky bruce
becky bruce
9
4.23%
2
15.38%
alexander duyck
alexander duyck
8
3.76%
2
15.38%
jesse barnes
jesse barnes
6
2.82%
1
7.69%
konrad rzeszutek wilk
konrad rzeszutek wilk
3
1.41%
2
15.38%
jeremy fitzhardinge
jeremy fitzhardinge
2
0.94%
1
7.69%
andre goddard rosa
andre goddard rosa
1
0.47%
1
7.69%
Total
213
100.00%
13
100.00%


EXPORT_SYMBOL_GPL(swiotlb_tbl_unmap_single);



void swiotlb_tbl_sync_single(struct device *hwdev, phys_addr_t tlb_addr,
			     size_t size, enum dma_data_direction dir,
			     enum dma_sync_target target)
{
	int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;
	phys_addr_t orig_addr = io_tlb_orig_addr[index];

	if (orig_addr == INVALID_PHYS_ADDR)
		return;
	orig_addr += (unsigned long)tlb_addr & ((1 << IO_TLB_SHIFT) - 1);

	switch (target) {
	case SYNC_FOR_CPU:
		if (likely(dir == DMA_FROM_DEVICE || dir == DMA_BIDIRECTIONAL))
			swiotlb_bounce(orig_addr, tlb_addr,
				       size, DMA_FROM_DEVICE);
		else
			BUG_ON(dir != DMA_TO_DEVICE);
		break;
	case SYNC_FOR_DEVICE:
		if (likely(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
			swiotlb_bounce(orig_addr, tlb_addr,
				       size, DMA_TO_DEVICE);
		else
			BUG_ON(dir != DMA_FROM_DEVICE);
		break;
	default:
		BUG();
	}
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
john w. linville
john w. linville
41
27.33%
1
6.67%
becky bruce
becky bruce
33
22.00%
2
13.33%
linus torvalds
linus torvalds
31
20.67%
1
6.67%
alexander duyck
alexander duyck
11
7.33%
1
6.67%
jan beulich
jan beulich
8
5.33%
2
13.33%
eric sesterhenn
eric sesterhenn
8
5.33%
1
6.67%
jeremy fitzhardinge
jeremy fitzhardinge
6
4.00%
2
13.33%
david mosberger
david mosberger
6
4.00%
1
6.67%
konrad rzeszutek wilk
konrad rzeszutek wilk
5
3.33%
3
20.00%
tony luck
tony luck
1
0.67%
1
6.67%
Total
150
100.00%
15
100.00%


EXPORT_SYMBOL_GPL(swiotlb_tbl_sync_single);


void *

swiotlb_alloc_coherent(struct device *hwdev, size_t size,
		       dma_addr_t *dma_handle, gfp_t flags)
{
	dma_addr_t dev_addr;
	void *ret;
	int order = get_order(size);
	u64 dma_mask = DMA_BIT_MASK(32);

	if (hwdev && hwdev->coherent_dma_mask)
		dma_mask = hwdev->coherent_dma_mask;

	ret = (void *)__get_free_pages(flags, order);
	if (ret) {
		dev_addr = swiotlb_virt_to_bus(hwdev, ret);
		if (dev_addr + size - 1 > dma_mask) {
			/*
                         * The allocated memory isn't reachable by the device.
                         */
			free_pages((unsigned long) ret, order);
			ret = NULL;
		}
	}
	if (!ret) {
		/*
                 * We are either out of memory or the device can't DMA to
                 * GFP_DMA memory; fall back on map_single(), which
                 * will grab memory from the lowest available address range.
                 */
		phys_addr_t paddr = map_single(hwdev, 0, size, DMA_FROM_DEVICE);
		if (paddr == SWIOTLB_MAP_ERROR)
			goto err_warn;

		ret = phys_to_virt(paddr);
		dev_addr = phys_to_dma(hwdev, paddr);

		/* Confirm address can be DMA'd by device */
		if (dev_addr + size - 1 > dma_mask) {
			printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n",
			       (unsigned long long)dma_mask,
			       (unsigned long long)dev_addr);

			/* DMA_TO_DEVICE to avoid memcpy in unmap_single */
			swiotlb_tbl_unmap_single(hwdev, paddr,
						 size, DMA_TO_DEVICE);
			goto err_warn;
		}
	}

	*dma_handle = dev_addr;
	memset(ret, 0, size);

	return ret;

err_warn:
	pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n",
		dev_name(hwdev), size);
	dump_stack();

	return NULL;
}
Contributors
Person
Tokens
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CommitProp
linus torvalds
linus torvalds
54
22.04%
1
4.35%
david mosberger
david mosberger
42
17.14%
2
8.70%
fujita tomonori
fujita tomonori
35
14.29%
5
21.74%
alexander duyck
alexander duyck
34
13.88%
2
8.70%
joerg roedel
joerg roedel
26
10.61%
1
4.35%
jan beulich
jan beulich
14
5.71%
3
13.04%
suresh siddha
suresh siddha
11
4.49%
1
4.35%
jesse barnes
jesse barnes
11
4.49%
1
4.35%
randy dunlap
randy dunlap
5
2.04%
1
4.35%
jeremy fitzhardinge
jeremy fitzhardinge
4
1.63%
1
4.35%
yang hongyang
yang hongyang
4
1.63%
1
4.35%
konrad rzeszutek wilk
konrad rzeszutek wilk
2
0.82%
1
4.35%
al viro
al viro
1
0.41%
1
4.35%
ian campbell
ian campbell
1
0.41%
1
4.35%
becky bruce
becky bruce
1
0.41%
1
4.35%
Total
245
100.00%
23
100.00%


EXPORT_SYMBOL(swiotlb_alloc_coherent);


void

swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
		      dma_addr_t dev_addr)
{
	phys_addr_t paddr = dma_to_phys(hwdev, dev_addr);

	WARN_ON(irqs_disabled());
	if (!is_swiotlb_buffer(paddr))
		free_pages((unsigned long)vaddr, get_order(size));
	else
		/* DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single */
		swiotlb_tbl_unmap_single(hwdev, paddr, size, DMA_TO_DEVICE);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
linus torvalds
linus torvalds
31
43.66%
1
11.11%
fujita tomonori
fujita tomonori
15
21.13%
3
33.33%
suresh siddha
suresh siddha
14
19.72%
1
11.11%
david brownell
david brownell
6
8.45%
1
11.11%
david mosberger
david mosberger
2
2.82%
1
11.11%
konrad rzeszutek wilk
konrad rzeszutek wilk
2
2.82%
1
11.11%
alexander duyck
alexander duyck
1
1.41%
1
11.11%
Total
71
100.00%
9
100.00%


EXPORT_SYMBOL(swiotlb_free_coherent);


static void

swiotlb_full(struct device *dev, size_t size, enum dma_data_direction dir,
	     int do_panic)
{
	/*
         * Ran out of IOMMU space for this operation. This is very bad.
         * Unfortunately the drivers cannot handle this operation properly.
         * unless they check for dma_mapping_error (most don't)
         * When the mapping is small enough return a static buffer to limit
         * the damage, or panic when the transfer is too big.
         */
	printk(KERN_ERR "DMA: Out of SW-IOMMU space for %zu bytes at "
	       "device %s\n", size, dev ? dev_name(dev) : "?");

	if (size <= io_tlb_overflow || !do_panic)
		return;

	if (dir == DMA_BIDIRECTIONAL)
		panic("DMA: Random memory could be DMA accessed\n");
	if (dir == DMA_FROM_DEVICE)
		panic("DMA: Random memory could be DMA written\n");
	if (dir == DMA_TO_DEVICE)
		panic("DMA: Random memory could be DMA read\n");
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
andi kleen
andi kleen
58
69.88%
1
14.29%
casey dahlin
casey dahlin
16
19.28%
1
14.29%
kay sievers
kay sievers
3
3.61%
1
14.29%
tony luck
tony luck
2
2.41%
1
14.29%
konrad rzeszutek wilk
konrad rzeszutek wilk
2
2.41%
1
14.29%
jan beulich
jan beulich
1
1.20%
1
14.29%
jesse barnes
jesse barnes
1
1.20%
1
14.29%
Total
83
100.00%
7
100.00%

/*
 * Map a single buffer of the indicated size for DMA in streaming mode.  The
 * physical address to use is returned.
 *
 * Once the device is given the dma address, the device owns this memory until
 * either swiotlb_unmap_page or swiotlb_dma_sync_single is performed.
 */


dma_addr_t swiotlb_map_page(struct device *dev, struct page *page,
			    unsigned long offset, size_t size,
			    enum dma_data_direction dir,
			    unsigned long attrs)
{
	phys_addr_t map, phys = page_to_phys(page) + offset;
	dma_addr_t dev_addr = phys_to_dma(dev, phys);

	BUG_ON(dir == DMA_NONE);
	/*
         * If the address happens to be in the device's DMA window,
         * we can safely return the device addr and not worry about bounce
         * buffering it.
         */
	if (dma_capable(dev, dev_addr, size) && !swiotlb_force)
		return dev_addr;

	trace_swiotlb_bounced(dev, dev_addr, size, swiotlb_force);

	/* Oh well, have to allocate and map a bounce buffer. */
	map = map_sing