Commit 73f62095 authored by Claire Chang's avatar Claire Chang Committed by Konrad Rzeszutek Wilk
Browse files

swiotlb: move global variables into a new io_tlb_mem structure 



Added a new struct, io_tlb_mem, as the IO TLB memory pool descriptor and
moved relevant global variables into that struct.
This will be useful later to allow for restricted DMA pool.

Signed-off-by: default avatarClaire Chang <tientzu@chromium.org>
[hch: rebased]
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
parent 6bcd4ea7

drivers/xen/swiotlb-xen.c

+1 −1
Original line number Diff line number Diff line
@@ -548,7 +548,7 @@ xen_swiotlb_sync_sg_for_device(struct device *dev, struct scatterlist *sgl, 
static int

xen_swiotlb_dma_supported(struct device *hwdev, u64 mask)

{

	return xen_phys_to_dma(hwdev, io_tlb_end - 1) <= mask;

	return xen_phys_to_dma(hwdev, io_tlb_default_mem.end - 1) <= mask;

}



const struct dma_map_ops xen_swiotlb_dma_ops = {

include/linux/swiotlb.h

+41 −2
Original line number Diff line number Diff line
@@ -6,6 +6,7 @@ 
#include <linux/init.h>

#include <linux/types.h>

#include <linux/limits.h>

#include <linux/spinlock.h>



struct device;

struct page;
@@ -61,11 +62,49 @@ dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys, 


#ifdef CONFIG_SWIOTLB

extern enum swiotlb_force swiotlb_force;

extern phys_addr_t io_tlb_start, io_tlb_end;



/**

 * struct io_tlb_mem - IO TLB Memory Pool Descriptor

 *

 * @start:	The start address of the swiotlb memory pool. Used to do a quick

 *		range check to see if the memory was in fact allocated by this

 *		API.

 * @end:	The end address of the swiotlb memory pool. Used to do a quick

 *		range check to see if the memory was in fact allocated by this

 *		API.

 * @nslabs:	The number of IO TLB blocks (in groups of 64) between @start and

 *		@end. This is command line adjustable via setup_io_tlb_npages.

 * @used:	The number of used IO TLB block.

 * @list:	The free list describing the number of free entries available

 *		from each index.

 * @index:	The index to start searching in the next round.

 * @orig_addr:	The original address corresponding to a mapped entry.

 * @alloc_size:	Size of the allocated buffer.

 * @lock:	The lock to protect the above data structures in the map and

 *		unmap calls.

 * @debugfs:	The dentry to debugfs.

 * @late_alloc:	%true if allocated using the page allocator

 */

struct io_tlb_mem {

	phys_addr_t start;

	phys_addr_t end;

	unsigned long nslabs;

	unsigned long used;

	unsigned int *list;

	unsigned int index;

	phys_addr_t *orig_addr;

	size_t *alloc_size;

	spinlock_t lock;

	struct dentry *debugfs;

	bool late_alloc;

};

extern struct io_tlb_mem io_tlb_default_mem;



static inline bool is_swiotlb_buffer(phys_addr_t paddr)

{

	return paddr >= io_tlb_start && paddr < io_tlb_end;

	struct io_tlb_mem *mem = &io_tlb_default_mem;



	return paddr >= mem->start && paddr < mem->end;

}



void __init swiotlb_exit(void);

kernel/dma/swiotlb.c

+164 −190
Original line number Diff line number Diff line
@@ -59,32 +59,11 @@ 
 */

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



enum swiotlb_force 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.

 */

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;

#define INVALID_PHYS_ADDR (~(phys_addr_t)0)



/*

 * The number of used IO TLB block

 */

static unsigned long io_tlb_used;

enum swiotlb_force swiotlb_force;



/*

 * 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;

struct io_tlb_mem io_tlb_default_mem;



/*

 * Max segment that we can provide which (if pages are contingous) will
@@ -92,32 +71,15 @@ static unsigned int io_tlb_index; 
 */

static unsigned int max_segment;



/*

 * 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;



/*

 * The mapped buffer's size should be validated during a sync operation.

 */

static size_t *io_tlb_alloc_size;



/*

 * 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)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;



	if (isdigit(*str)) {

		io_tlb_nslabs = simple_strtoul(str, &str, 0);

		mem->nslabs = simple_strtoul(str, &str, 0);

		/* avoid tail segment of size < IO_TLB_SEGSIZE */

		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);

		mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE);

	}

	if (*str == ',')

		++str;
@@ -125,7 +87,7 @@ setup_io_tlb_npages(char *str) 
		swiotlb_force = SWIOTLB_FORCE;

	} else if (!strcmp(str, "noforce")) {

		swiotlb_force = SWIOTLB_NO_FORCE;

		io_tlb_nslabs = 1;

		mem->nslabs = 1;

	}



	return 0;
@@ -136,7 +98,7 @@ static bool no_iotlb_memory; 


unsigned long swiotlb_nr_tbl(void)

{

	return unlikely(no_iotlb_memory) ? 0 : io_tlb_nslabs;

	return unlikely(no_iotlb_memory) ? 0 : io_tlb_default_mem.nslabs;

}

EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);
@@ -158,13 +120,14 @@ unsigned long swiotlb_size_or_default(void) 
{

	unsigned long size;



	size = io_tlb_nslabs << IO_TLB_SHIFT;

	size = io_tlb_default_mem.nslabs << IO_TLB_SHIFT;



	return size ? size : (IO_TLB_DEFAULT_SIZE);

}



void __init swiotlb_adjust_size(unsigned long new_size)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long size;



	/*
@@ -172,10 +135,10 @@ void __init swiotlb_adjust_size(unsigned long new_size) 
	 * architectures such as those supporting memory encryption to

	 * adjust/expand SWIOTLB size for their use.

	 */

	if (!io_tlb_nslabs) {

	if (!mem->nslabs) {

		size = ALIGN(new_size, IO_TLB_SIZE);

		io_tlb_nslabs = size >> IO_TLB_SHIFT;

		io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);

		mem->nslabs = size >> IO_TLB_SHIFT;

		mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE);



		pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20);

	}
@@ -183,14 +146,15 @@ void __init swiotlb_adjust_size(unsigned long new_size) 


void swiotlb_print_info(void)

{

	unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long bytes = mem->nslabs << IO_TLB_SHIFT;



	if (no_iotlb_memory) {

		pr_warn("No low mem\n");

		return;

	}



	pr_info("mapped [mem %pa-%pa] (%luMB)\n", &io_tlb_start, &io_tlb_end,

	pr_info("mapped [mem %pa-%pa] (%luMB)\n", &mem->start, &mem->end,

	       bytes >> 20);

}
@@ -212,68 +176,71 @@ static inline unsigned long nr_slots(u64 val) 
 */

void __init swiotlb_update_mem_attributes(void)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	void *vaddr;

	unsigned long bytes;



	if (no_iotlb_memory || late_alloc)

	if (no_iotlb_memory || mem->late_alloc)

		return;



	vaddr = phys_to_virt(io_tlb_start);

	bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT);

	vaddr = phys_to_virt(mem->start);

	bytes = PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT);

	set_memory_decrypted((unsigned long)vaddr, bytes >> PAGE_SHIFT);

	memset(vaddr, 0, bytes);

}



int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long i, bytes;

	size_t alloc_size;



	/* protect against double initialization */

	if (WARN_ON_ONCE(io_tlb_start))

	if (WARN_ON_ONCE(mem->start))

		return -ENOMEM;



	bytes = nslabs << IO_TLB_SHIFT;



	io_tlb_nslabs = nslabs;

	io_tlb_start = __pa(tlb);

	io_tlb_end = io_tlb_start + bytes;

	mem->nslabs = nslabs;

	mem->start = __pa(tlb);

	mem->end = mem->start + bytes;

	mem->index = 0;

	spin_lock_init(&mem->lock);



	/*

	 * 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.

	 * between mem->start and mem->end.

	 */

	alloc_size = PAGE_ALIGN(io_tlb_nslabs * sizeof(int));

	io_tlb_list = memblock_alloc(alloc_size, PAGE_SIZE);

	if (!io_tlb_list)

	alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(int));

	mem->list = memblock_alloc(alloc_size, PAGE_SIZE);

	if (!mem->list)

		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",

		      __func__, alloc_size, PAGE_SIZE);



	alloc_size = PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t));

	io_tlb_orig_addr = memblock_alloc(alloc_size, PAGE_SIZE);

	if (!io_tlb_orig_addr)

	alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(phys_addr_t));

	mem->orig_addr = memblock_alloc(alloc_size, PAGE_SIZE);

	if (!mem->orig_addr)

		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",

		      __func__, alloc_size, PAGE_SIZE);



	alloc_size = PAGE_ALIGN(io_tlb_nslabs * sizeof(size_t));

	io_tlb_alloc_size = memblock_alloc(alloc_size, PAGE_SIZE);

	if (!io_tlb_alloc_size)

	alloc_size = PAGE_ALIGN(mem->nslabs * sizeof(size_t));

	mem->alloc_size = memblock_alloc(alloc_size, PAGE_SIZE);

	if (mem->alloc_size)

		panic("%s: Failed to allocate %zu bytes align=0x%lx\n",

		      __func__, alloc_size, PAGE_SIZE);



	for (i = 0; i < io_tlb_nslabs; i++) {

		io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);

		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;

		io_tlb_alloc_size[i] = 0;

	for (i = 0; i < mem->nslabs; i++) {

		mem->list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);

		mem->orig_addr[i] = INVALID_PHYS_ADDR;

		mem->alloc_size[i] = 0;

	}

	io_tlb_index = 0;

	no_iotlb_memory = false;



	if (verbose)

		swiotlb_print_info();



	swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);

	swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);

	return 0;

}
@@ -284,26 +251,27 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose) 
void  __init

swiotlb_init(int verbose)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	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);

	if (!mem->nslabs) {

		mem->nslabs = (default_size >> IO_TLB_SHIFT);

		mem->nslabs = ALIGN(mem->nslabs, IO_TLB_SEGSIZE);

	}



	bytes = io_tlb_nslabs << IO_TLB_SHIFT;

	bytes = mem->nslabs << IO_TLB_SHIFT;



	/* Get IO TLB memory from the low pages */

	vstart = memblock_alloc_low(PAGE_ALIGN(bytes), PAGE_SIZE);

	if (vstart && !swiotlb_init_with_tbl(vstart, io_tlb_nslabs, verbose))

	if (vstart && !swiotlb_init_with_tbl(vstart, mem->nslabs, verbose))

		return;



	if (io_tlb_start) {

		memblock_free_early(io_tlb_start,

				    PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT));

		io_tlb_start = 0;

	if (mem->start) {

		memblock_free_early(mem->start,

				    PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT));

		mem->start = 0;

	}

	pr_warn("Cannot allocate buffer");

	no_iotlb_memory = true;
@@ -317,22 +285,23 @@ swiotlb_init(int verbose) 
int

swiotlb_late_init_with_default_size(size_t default_size)

{

	unsigned long bytes, req_nslabs = io_tlb_nslabs;

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long bytes, req_nslabs = mem->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);

	if (!mem->nslabs) {

		mem->nslabs = (default_size >> IO_TLB_SHIFT);

		mem->nslabs = ALIGN(mem->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;

	order = get_order(mem->nslabs << IO_TLB_SHIFT);

	mem->nslabs = SLABS_PER_PAGE << order;

	bytes = mem->nslabs << IO_TLB_SHIFT;



	while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {

		vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
@@ -343,15 +312,15 @@ swiotlb_late_init_with_default_size(size_t default_size) 
	}



	if (!vstart) {

		io_tlb_nslabs = req_nslabs;

		mem->nslabs = req_nslabs;

		return -ENOMEM;

	}

	if (order != get_order(bytes)) {

		pr_warn("only able to allocate %ld MB\n",

			(PAGE_SIZE << order) >> 20);

		io_tlb_nslabs = SLABS_PER_PAGE << order;

		mem->nslabs = SLABS_PER_PAGE << order;

	}

	rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);

	rc = swiotlb_late_init_with_tbl(vstart, mem->nslabs);

	if (rc)

		free_pages((unsigned long)vstart, order);
@@ -360,26 +329,32 @@ swiotlb_late_init_with_default_size(size_t default_size) 


static void swiotlb_cleanup(void)

{

	io_tlb_end = 0;

	io_tlb_start = 0;

	io_tlb_nslabs = 0;

	struct io_tlb_mem *mem = &io_tlb_default_mem;



	mem->end = 0;

	mem->start = 0;

	mem->nslabs = 0;

	max_segment = 0;

}



int

swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long i, bytes;



	/* protect against double initialization */

	if (WARN_ON_ONCE(io_tlb_start))

	if (WARN_ON_ONCE(mem->start))

		return -ENOMEM;



	bytes = nslabs << IO_TLB_SHIFT;



	io_tlb_nslabs = nslabs;

	io_tlb_start = virt_to_phys(tlb);

	io_tlb_end = io_tlb_start + bytes;

	mem->nslabs = nslabs;

	mem->start = virt_to_phys(tlb);

	mem->end = mem->start + bytes;

	mem->index = 0;

	mem->late_alloc = 1;

	spin_lock_init(&mem->lock);



	set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);

	memset(tlb, 0, bytes);
@@ -387,52 +362,45 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) 
	/*

	 * 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.

	 * between mem->start and mem->end.

	 */

	io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,

				      get_order(io_tlb_nslabs * sizeof(int)));

	if (!io_tlb_list)

	mem->list = (unsigned int *)__get_free_pages(GFP_KERNEL,

	                              get_order(mem->nslabs * sizeof(int)));

	if (!mem->list)

		goto cleanup3;



	io_tlb_orig_addr = (phys_addr_t *)

	mem->orig_addr = (phys_addr_t *)

		__get_free_pages(GFP_KERNEL,

				 get_order(io_tlb_nslabs *

				 get_order(mem->nslabs *

					   sizeof(phys_addr_t)));

	if (!io_tlb_orig_addr)

	if (!mem->orig_addr)

		goto cleanup4;



	io_tlb_alloc_size = (size_t *)

	mem->alloc_size = (size_t *)

		__get_free_pages(GFP_KERNEL,

				 get_order(io_tlb_nslabs *

				 get_order(mem->nslabs *

					   sizeof(size_t)));

	if (!io_tlb_alloc_size)

	if (!mem->alloc_size)

		goto cleanup5;





	for (i = 0; i < io_tlb_nslabs; i++) {

		io_tlb_list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);

		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;

		io_tlb_alloc_size[i] = 0;

	for (i = 0; i < mem->nslabs; i++) {

		mem->list[i] = IO_TLB_SEGSIZE - io_tlb_offset(i);

		mem->orig_addr[i] = INVALID_PHYS_ADDR;

		mem->alloc_size[i] = 0;

	}

	io_tlb_index = 0;

	no_iotlb_memory = false;



	swiotlb_print_info();



	late_alloc = 1;



	swiotlb_set_max_segment(io_tlb_nslabs << IO_TLB_SHIFT);



	swiotlb_set_max_segment(mem->nslabs << IO_TLB_SHIFT);

	return 0;



cleanup5:

	free_pages((unsigned long)io_tlb_orig_addr, get_order(io_tlb_nslabs *

							      sizeof(phys_addr_t)));



	free_pages((unsigned long)mem->orig_addr,

		   get_order(mem->nslabs * sizeof(phys_addr_t)));

cleanup4:

	free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *

	                                                 sizeof(int)));

	io_tlb_list = NULL;

	free_pages((unsigned long)mem->list,

		   get_order(mem->nslabs * sizeof(int)));

	mem->list = NULL;

cleanup3:

	swiotlb_cleanup();

	return -ENOMEM;
@@ -440,27 +408,29 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs) 


void __init swiotlb_exit(void)

{

	if (!io_tlb_orig_addr)

	struct io_tlb_mem *mem = &io_tlb_default_mem;



	if (!mem->orig_addr)

		return;



	if (late_alloc) {

		free_pages((unsigned long)io_tlb_alloc_size,

			   get_order(io_tlb_nslabs * sizeof(size_t)));

		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));

	if (mem->late_alloc) {

		free_pages((unsigned long)mem->alloc_size,

			   get_order(mem->nslabs * sizeof(size_t)));

		free_pages((unsigned long)mem->orig_addr,

			   get_order(mem->nslabs * sizeof(phys_addr_t)));

		free_pages((unsigned long)mem->list,

			   get_order(mem->nslabs * sizeof(int)));

		free_pages((unsigned long)phys_to_virt(mem->start),

			   get_order(mem->nslabs << IO_TLB_SHIFT));

	} else {

		memblock_free_late(__pa(io_tlb_orig_addr),

				   PAGE_ALIGN(io_tlb_nslabs * sizeof(phys_addr_t)));

		memblock_free_late(__pa(io_tlb_alloc_size),

				   PAGE_ALIGN(io_tlb_nslabs * sizeof(size_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));

		memblock_free_late(__pa(mem->alloc_size),

				   PAGE_ALIGN(mem->nslabs * sizeof(size_t)));

		memblock_free_late(__pa(mem->orig_addr),

				   PAGE_ALIGN(mem->nslabs * sizeof(phys_addr_t)));

		memblock_free_late(__pa(mem->list),

				   PAGE_ALIGN(mem->nslabs * sizeof(int)));

		memblock_free_late(mem->start,

				   PAGE_ALIGN(mem->nslabs << IO_TLB_SHIFT));

	}

	swiotlb_cleanup();

}
@@ -471,9 +441,10 @@ void __init swiotlb_exit(void) 
static void swiotlb_bounce(struct device *dev, phys_addr_t tlb_addr, size_t size,

			   enum dma_data_direction dir)

{

	int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT;

	size_t alloc_size = io_tlb_alloc_size[index];

	phys_addr_t orig_addr = io_tlb_orig_addr[index];

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	int index = (tlb_addr - mem->start) >> IO_TLB_SHIFT;

	phys_addr_t orig_addr = mem->orig_addr[index];

	size_t alloc_size = mem->alloc_size[index];

	unsigned long pfn = PFN_DOWN(orig_addr);

	unsigned char *vaddr = phys_to_virt(tlb_addr);
@@ -538,9 +509,9 @@ static inline unsigned long get_max_slots(unsigned long boundary_mask) 
	return nr_slots(boundary_mask + 1);

}



static unsigned int wrap_index(unsigned int index)

static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)

{

	if (index >= io_tlb_nslabs)

	if (index >= mem->nslabs)

		return 0;

	return index;

}
@@ -552,9 +523,10 @@ static unsigned int wrap_index(unsigned int index) 
static int find_slots(struct device *dev, phys_addr_t orig_addr,

		size_t alloc_size)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long boundary_mask = dma_get_seg_boundary(dev);

	dma_addr_t tbl_dma_addr =

		phys_to_dma_unencrypted(dev, io_tlb_start) & boundary_mask;

		phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;

	unsigned long max_slots = get_max_slots(boundary_mask);

	unsigned int iotlb_align_mask =

		dma_get_min_align_mask(dev) & ~(IO_TLB_SIZE - 1);
@@ -573,15 +545,15 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr, 
	if (alloc_size >= PAGE_SIZE)

		stride = max(stride, stride << (PAGE_SHIFT - IO_TLB_SHIFT));



	spin_lock_irqsave(&io_tlb_lock, flags);

	if (unlikely(nslots > io_tlb_nslabs - io_tlb_used))

	spin_lock_irqsave(&mem->lock, flags);

	if (unlikely(nslots > mem->nslabs - mem->used))

		goto not_found;



	index = wrap = wrap_index(ALIGN(io_tlb_index, stride));

	index = wrap = wrap_index(mem, ALIGN(mem->index, stride));

	do {

		if ((slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=

		    (orig_addr & iotlb_align_mask)) {

			index = wrap_index(index + 1);

			index = wrap_index(mem, index + 1);

			continue;

		}
@@ -593,34 +565,34 @@ static int find_slots(struct device *dev, phys_addr_t orig_addr, 
		if (!iommu_is_span_boundary(index, nslots,

					    nr_slots(tbl_dma_addr),

					    max_slots)) {

			if (io_tlb_list[index] >= nslots)

			if (mem->list[index] >= nslots)

				goto found;

		}

		index = wrap_index(index + stride);

		index = wrap_index(mem, index + stride);

	} while (index != wrap);



not_found:

	spin_unlock_irqrestore(&io_tlb_lock, flags);

	spin_unlock_irqrestore(&mem->lock, flags);

	return -1;



found:

	for (i = index; i < index + nslots; i++)

		io_tlb_list[i] = 0;

		mem->list[i] = 0;

	for (i = index - 1;

	     io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&

	     io_tlb_list[i]; i--)

		io_tlb_list[i] = ++count;

	     mem->list[i]; i--)

		mem->list[i] = ++count;



	/*

	 * Update the indices to avoid searching in the next round.

	 */

	if (index + nslots < io_tlb_nslabs)

		io_tlb_index = index + nslots;

	if (index + nslots < mem->nslabs)

		mem->index = index + nslots;

	else

		io_tlb_index = 0;

	io_tlb_used += nslots;

		mem->index = 0;

	mem->used += nslots;



	spin_unlock_irqrestore(&io_tlb_lock, flags);

	spin_unlock_irqrestore(&mem->lock, flags);

	return index;

}
@@ -628,6 +600,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, 
		size_t mapping_size, size_t alloc_size,

		enum dma_data_direction dir, unsigned long attrs)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned int offset = swiotlb_align_offset(dev, orig_addr);

	unsigned int index, i;

	phys_addr_t tlb_addr;
@@ -649,7 +622,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, 
		if (!(attrs & DMA_ATTR_NO_WARN))

			dev_warn_ratelimited(dev,

	"swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n",

				 alloc_size, io_tlb_nslabs, io_tlb_used);

				 alloc_size, mem->nslabs, mem->used);

		return (phys_addr_t)DMA_MAPPING_ERROR;

	}
@@ -659,10 +632,10 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, 
	 * needed.

	 */

	for (i = 0; i < nr_slots(alloc_size + offset); i++) {

		io_tlb_orig_addr[index + i] = slot_addr(orig_addr, i);

		io_tlb_alloc_size[index+i] = alloc_size - (i << IO_TLB_SHIFT);

		mem->orig_addr[index + i] = slot_addr(orig_addr, i);

		mem->alloc_size[index + i] = alloc_size - (i << IO_TLB_SHIFT);

	}

	tlb_addr = slot_addr(io_tlb_start, index) + offset;

	tlb_addr = slot_addr(mem->start, index) + offset;

	if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&

	    (dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))

		swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_TO_DEVICE);
@@ -676,10 +649,11 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, 
			      size_t mapping_size, enum dma_data_direction dir,

			      unsigned long attrs)

{

	struct io_tlb_mem *mem = &io_tlb_default_mem;

	unsigned long flags;

	unsigned int offset = swiotlb_align_offset(hwdev, tlb_addr);

	int index = (tlb_addr - offset - io_tlb_start) >> IO_TLB_SHIFT;

	int nslots = nr_slots(io_tlb_alloc_size[index] + offset);

	int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;

	int nslots = nr_slots(mem->alloc_size[index] + offset);

	int count, i;



	/*
@@ -695,9 +669,9 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, 
	 * 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);

	spin_lock_irqsave(&mem->lock, flags);

	if (index + nslots < ALIGN(index + 1, IO_TLB_SEGSIZE))

		count = io_tlb_list[index + nslots];

		count = mem->list[index + nslots];

	else

		count = 0;
@@ -706,9 +680,9 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, 
	 * superceeding slots

	 */

	for (i = index + nslots - 1; i >= index; i--) {

		io_tlb_list[i] = ++count;

		io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;

		io_tlb_alloc_size[i] = 0;

		mem->list[i] = ++count;

		mem->orig_addr[i] = INVALID_PHYS_ADDR;

		mem->alloc_size[i] = 0;

	}



	/*
@@ -716,11 +690,11 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, 
	 * available (non zero)

	 */

	for (i = index - 1;

	     io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && io_tlb_list[i];

	     io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && mem->list[i];

	     i--)

		io_tlb_list[i] = ++count;

	io_tlb_used -= nslots;

	spin_unlock_irqrestore(&io_tlb_lock, flags);

		mem->list[i] = ++count;

	mem->used -= nslots;

	spin_unlock_irqrestore(&mem->lock, flags);

}



void swiotlb_sync_single_for_device(struct device *dev, phys_addr_t tlb_addr,
@@ -783,21 +757,21 @@ size_t swiotlb_max_mapping_size(struct device *dev) 
bool is_swiotlb_active(void)

{

	/*

	 * When SWIOTLB is initialized, even if io_tlb_start points to physical

	 * address zero, io_tlb_end surely doesn't.

	 * When SWIOTLB is initialized, even if mem->start points to physical

	 * address zero, mem->end surely doesn't.

	 */

	return io_tlb_end != 0;

	return io_tlb_default_mem.end != 0;

}



#ifdef CONFIG_DEBUG_FS



static int __init swiotlb_create_debugfs(void)

{

	struct dentry *root;

	struct io_tlb_mem *mem = &io_tlb_default_mem;



	root = debugfs_create_dir("swiotlb", NULL);

	debugfs_create_ulong("io_tlb_nslabs", 0400, root, &io_tlb_nslabs);

	debugfs_create_ulong("io_tlb_used", 0400, root, &io_tlb_used);

	mem->debugfs = debugfs_create_dir("swiotlb", NULL);

	debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);

	debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);

	return 0;

}