[PATCH v4 03/14] swiotlb: Add struct swiotlb

From: Claire Chang
Date: Tue Feb 09 2021 - 01:25:19 EST

Added a new struct, swiotlb, 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: Claire Chang <tientzu@xxxxxxxxxxxx>
---
kernel/dma/swiotlb.c | 327 +++++++++++++++++++++++--------------------
1 file changed, 172 insertions(+), 155 deletions(-)

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 678490d39e55..28b7bfe7a2a8 100644
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -61,33 +61,43 @@
* allocate a contiguous 1MB, we're probably in trouble anyway.
*/
#define IO_TLB_MIN_SLABS ((1<<20) >> IO_TLB_SHIFT)
+#define INVALID_PHYS_ADDR (~(phys_addr_t)0)

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.
- */
-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;
-
-/*
- * The number of used IO TLB block
- */
-static unsigned long io_tlb_used;
-
-/*
- * This is a free list describing the number of free entries available from
- * each index
+ * struct swiotlb - Software 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 for the
+ * sync operations.
+ * @lock: The lock to protect the above data structures in the map and
+ * unmap calls.
+ * @debugfs: The dentry to debugfs.
*/
-static unsigned int *io_tlb_list;
-static unsigned int io_tlb_index;
+struct swiotlb {
+ 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;
+ spinlock_t lock;
+ struct dentry *debugfs;
+};
+static struct swiotlb default_swiotlb;

/*
* Max segment that we can provide which (if pages are contingous) will
@@ -95,27 +105,17 @@ 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;
-
-/*
- * 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 swiotlb *swiotlb = &default_swiotlb;
+
if (isdigit(*str)) {
- io_tlb_nslabs = simple_strtoul(str, &str, 0);
+ swiotlb->nslabs = simple_strtoul(str, &str, 0);
/* avoid tail segment of size < IO_TLB_SEGSIZE */
- io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ swiotlb->nslabs = ALIGN(swiotlb->nslabs, IO_TLB_SEGSIZE);
}
if (*str == ',')
++str;
@@ -123,7 +123,7 @@ setup_io_tlb_npages(char *str)
swiotlb_force = SWIOTLB_FORCE;
} else if (!strcmp(str, "noforce")) {
swiotlb_force = SWIOTLB_NO_FORCE;
- io_tlb_nslabs = 1;
+ swiotlb->nslabs = 1;
}

return 0;
@@ -134,7 +134,7 @@ 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 : default_swiotlb.nslabs;
}
EXPORT_SYMBOL_GPL(swiotlb_nr_tbl);

@@ -156,13 +156,14 @@ unsigned long swiotlb_size_or_default(void)
{
unsigned long size;

- size = io_tlb_nslabs << IO_TLB_SHIFT;
+ size = default_swiotlb.nslabs << IO_TLB_SHIFT;

return size ? size : (IO_TLB_DEFAULT_SIZE);
}

void __init swiotlb_adjust_size(unsigned long new_size)
{
+ struct swiotlb *swiotlb = &default_swiotlb;
unsigned long size;

/*
@@ -170,10 +171,10 @@ 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 (!swiotlb->nslabs) {
size = ALIGN(new_size, 1 << IO_TLB_SHIFT);
- io_tlb_nslabs = size >> IO_TLB_SHIFT;
- io_tlb_nslabs = ALIGN(io_tlb_nslabs, IO_TLB_SEGSIZE);
+ swiotlb->nslabs = size >> IO_TLB_SHIFT;
+ swiotlb->nslabs = ALIGN(swiotlb->nslabs, IO_TLB_SEGSIZE);

pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20);
}
@@ -181,14 +182,15 @@ void __init swiotlb_adjust_size(unsigned long new_size)

void swiotlb_print_info(void)
{
- unsigned long bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+ struct swiotlb *swiotlb = &default_swiotlb;
+ unsigned long bytes = swiotlb->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", &swiotlb->start, &swiotlb->end,
bytes >> 20);
}

@@ -200,57 +202,61 @@ void swiotlb_print_info(void)
*/
void __init swiotlb_update_mem_attributes(void)
{
+ struct swiotlb *swiotlb = &default_swiotlb;
void *vaddr;
unsigned long bytes;

if (no_iotlb_memory || late_alloc)
return;

- vaddr = phys_to_virt(io_tlb_start);
- bytes = PAGE_ALIGN(io_tlb_nslabs << IO_TLB_SHIFT);
+ vaddr = phys_to_virt(swiotlb->start);
+ bytes = PAGE_ALIGN(swiotlb->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 swiotlb *swiotlb = &default_swiotlb;
unsigned long i, bytes;
size_t alloc_size;

bytes = nslabs << IO_TLB_SHIFT;

- io_tlb_nslabs = nslabs;
- io_tlb_start = __pa(tlb);
- io_tlb_end = io_tlb_start + bytes;
+ swiotlb->nslabs = nslabs;
+ swiotlb->start = __pa(tlb);
+ swiotlb->end = swiotlb->start + bytes;

/*
* 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 swiotlb->start and swiotlb->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(swiotlb->nslabs * sizeof(int));
+ swiotlb->list = memblock_alloc(alloc_size, PAGE_SIZE);
+ if (!swiotlb->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(swiotlb->nslabs * sizeof(phys_addr_t));
+ swiotlb->orig_addr = memblock_alloc(alloc_size, PAGE_SIZE);
+ if (!swiotlb->orig_addr)
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 - OFFSET(i, IO_TLB_SEGSIZE);
- io_tlb_orig_addr[i] = INVALID_PHYS_ADDR;
+ for (i = 0; i < swiotlb->nslabs; i++) {
+ swiotlb->list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ swiotlb->orig_addr[i] = INVALID_PHYS_ADDR;
}
- io_tlb_index = 0;
+ swiotlb->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(swiotlb->nslabs << IO_TLB_SHIFT);
+ spin_lock_init(&swiotlb->lock);
+
return 0;
}

@@ -261,26 +267,27 @@ int __init swiotlb_init_with_tbl(char *tlb, unsigned long nslabs, int verbose)
void __init
swiotlb_init(int verbose)
{
+ struct swiotlb *swiotlb = &default_swiotlb;
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 (!swiotlb->nslabs) {
+ swiotlb->nslabs = (default_size >> IO_TLB_SHIFT);
+ swiotlb->nslabs = ALIGN(swiotlb->nslabs, IO_TLB_SEGSIZE);
}

- bytes = io_tlb_nslabs << IO_TLB_SHIFT;
+ bytes = swiotlb->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, swiotlb->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 (swiotlb->start) {
+ memblock_free_early(swiotlb->start,
+ PAGE_ALIGN(swiotlb->nslabs << IO_TLB_SHIFT));
+ swiotlb->start = 0;
}
pr_warn("Cannot allocate buffer");
no_iotlb_memory = true;
@@ -294,22 +301,23 @@ swiotlb_init(int verbose)
int
swiotlb_late_init_with_default_size(size_t default_size)
{
- unsigned long bytes, req_nslabs = io_tlb_nslabs;
+ struct swiotlb *swiotlb = &default_swiotlb;
+ unsigned long bytes, req_nslabs = swiotlb->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 (!swiotlb->nslabs) {
+ swiotlb->nslabs = (default_size >> IO_TLB_SHIFT);
+ swiotlb->nslabs = ALIGN(swiotlb->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(swiotlb->nslabs << IO_TLB_SHIFT);
+ swiotlb->nslabs = SLABS_PER_PAGE << order;
+ bytes = swiotlb->nslabs << IO_TLB_SHIFT;

while ((SLABS_PER_PAGE << order) > IO_TLB_MIN_SLABS) {
vstart = (void *)__get_free_pages(GFP_DMA | __GFP_NOWARN,
@@ -320,15 +328,15 @@ swiotlb_late_init_with_default_size(size_t default_size)
}

if (!vstart) {
- io_tlb_nslabs = req_nslabs;
+ swiotlb->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;
+ swiotlb->nslabs = SLABS_PER_PAGE << order;
}
- rc = swiotlb_late_init_with_tbl(vstart, io_tlb_nslabs);
+ rc = swiotlb_late_init_with_tbl(vstart, swiotlb->nslabs);
if (rc)
free_pages((unsigned long)vstart, order);

@@ -337,22 +345,25 @@ 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 swiotlb *swiotlb = &default_swiotlb;
+
+ swiotlb->end = 0;
+ swiotlb->start = 0;
+ swiotlb->nslabs = 0;
max_segment = 0;
}

int
swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
{
+ struct swiotlb *swiotlb = &default_swiotlb;
unsigned long i, bytes;

bytes = nslabs << IO_TLB_SHIFT;

- io_tlb_nslabs = nslabs;
- io_tlb_start = virt_to_phys(tlb);
- io_tlb_end = io_tlb_start + bytes;
+ swiotlb->nslabs = nslabs;
+ swiotlb->start = virt_to_phys(tlb);
+ swiotlb->end = swiotlb->start + bytes;

set_memory_decrypted((unsigned long)tlb, bytes >> PAGE_SHIFT);
memset(tlb, 0, bytes);
@@ -360,39 +371,40 @@ 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 swiotlb->start and swiotlb->end.
*/
- io_tlb_list = (unsigned int *)__get_free_pages(GFP_KERNEL,
- get_order(io_tlb_nslabs * sizeof(int)));
- if (!io_tlb_list)
+ swiotlb->list = (unsigned int *)__get_free_pages(GFP_KERNEL,
+ get_order(swiotlb->nslabs * sizeof(int)));
+ if (!swiotlb->list)
goto cleanup3;

- io_tlb_orig_addr = (phys_addr_t *)
+ swiotlb->orig_addr = (phys_addr_t *)
__get_free_pages(GFP_KERNEL,
- get_order(io_tlb_nslabs *
+ get_order(swiotlb->nslabs *
sizeof(phys_addr_t)));
- if (!io_tlb_orig_addr)
+ if (!swiotlb->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;
+ for (i = 0; i < swiotlb->nslabs; i++) {
+ swiotlb->list[i] = IO_TLB_SEGSIZE - OFFSET(i, IO_TLB_SEGSIZE);
+ swiotlb->orig_addr[i] = INVALID_PHYS_ADDR;
}
- io_tlb_index = 0;
+ swiotlb->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(swiotlb->nslabs << IO_TLB_SHIFT);
+ spin_lock_init(&swiotlb->lock);

return 0;

cleanup4:
- free_pages((unsigned long)io_tlb_list, get_order(io_tlb_nslabs *
- sizeof(int)));
- io_tlb_list = NULL;
+ free_pages((unsigned long)swiotlb->list,
+ get_order(swiotlb->nslabs * sizeof(int)));
+ swiotlb->list = NULL;
cleanup3:
swiotlb_cleanup();
return -ENOMEM;
@@ -400,23 +412,25 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)

void __init swiotlb_exit(void)
{
- if (!io_tlb_orig_addr)
+ struct swiotlb *swiotlb = &default_swiotlb;
+
+ if (!swiotlb->orig_addr)
return;

if (late_alloc) {
- 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));
+ free_pages((unsigned long)swiotlb->orig_addr,
+ get_order(swiotlb->nslabs * sizeof(phys_addr_t)));
+ free_pages((unsigned long)swiotlb->list,
+ get_order(swiotlb->nslabs * sizeof(int)));
+ free_pages((unsigned long)phys_to_virt(swiotlb->start),
+ get_order(swiotlb->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_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(swiotlb->orig_addr),
+ PAGE_ALIGN(swiotlb->nslabs * sizeof(phys_addr_t)));
+ memblock_free_late(__pa(swiotlb->list),
+ PAGE_ALIGN(swiotlb->nslabs * sizeof(int)));
+ memblock_free_late(swiotlb->start,
+ PAGE_ALIGN(swiotlb->nslabs << IO_TLB_SHIFT));
}
swiotlb_cleanup();
}
@@ -465,7 +479,8 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
size_t mapping_size, size_t alloc_size,
enum dma_data_direction dir, unsigned long attrs)
{
- dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(hwdev, io_tlb_start);
+ struct swiotlb *swiotlb = &default_swiotlb;
+ dma_addr_t tbl_dma_addr = phys_to_dma_unencrypted(hwdev, swiotlb->start);
unsigned long flags;
phys_addr_t tlb_addr;
unsigned int nslots, stride, index, wrap;
@@ -516,13 +531,13 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
* 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);
+ spin_lock_irqsave(&swiotlb->lock, flags);

- if (unlikely(nslots > io_tlb_nslabs - io_tlb_used))
+ if (unlikely(nslots > swiotlb->nslabs - swiotlb->used))
goto not_found;

- index = ALIGN(io_tlb_index, stride);
- if (index >= io_tlb_nslabs)
+ index = ALIGN(swiotlb->index, stride);
+ if (index >= swiotlb->nslabs)
index = 0;
wrap = index;

@@ -530,7 +545,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
while (iommu_is_span_boundary(index, nslots, offset_slots,
max_slots)) {
index += stride;
- if (index >= io_tlb_nslabs)
+ if (index >= swiotlb->nslabs)
index = 0;
if (index == wrap)
goto not_found;
@@ -541,40 +556,40 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
* contiguous buffers, we allocate the buffers from that slot
* and mark the entries as '0' indicating unavailable.
*/
- if (io_tlb_list[index] >= nslots) {
+ if (swiotlb->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);
+ swiotlb->list[i] = 0;
+ for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE - 1) && swiotlb->list[i]; i--)
+ swiotlb->list[i] = ++count;
+ tlb_addr = swiotlb->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);
+ swiotlb->index = ((index + nslots) < swiotlb->nslabs
+ ? (index + nslots) : 0);

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

not_found:
- tmp_io_tlb_used = io_tlb_used;
+ tmp_io_tlb_used = swiotlb->used;

- spin_unlock_irqrestore(&io_tlb_lock, flags);
+ spin_unlock_irqrestore(&swiotlb->lock, flags);
if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit())
dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes), total %lu (slots), used %lu (slots)\n",
- alloc_size, io_tlb_nslabs, tmp_io_tlb_used);
+ alloc_size, swiotlb->nslabs, tmp_io_tlb_used);
return (phys_addr_t)DMA_MAPPING_ERROR;
found:
- io_tlb_used += nslots;
- spin_unlock_irqrestore(&io_tlb_lock, flags);
+ swiotlb->used += nslots;
+ spin_unlock_irqrestore(&swiotlb->lock, flags);

/*
* Save away the mapping from the original address to the DMA address.
@@ -582,7 +597,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t orig_addr,
* needed.
*/
for (i = 0; i < nslots; i++)
- io_tlb_orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT);
+ swiotlb->orig_addr[index+i] = orig_addr + (i << IO_TLB_SHIFT);
if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC) &&
(dir == DMA_TO_DEVICE || dir == DMA_BIDIRECTIONAL))
swiotlb_bounce(orig_addr, tlb_addr, mapping_size, DMA_TO_DEVICE);
@@ -597,10 +612,11 @@ void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr,
size_t mapping_size, size_t alloc_size,
enum dma_data_direction dir, unsigned long attrs)
{
+ struct swiotlb *swiotlb = &default_swiotlb;
unsigned long flags;
int i, count, nslots = ALIGN(alloc_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];
+ int index = (tlb_addr - swiotlb->start) >> IO_TLB_SHIFT;
+ phys_addr_t orig_addr = swiotlb->orig_addr[index];

/*
* First, sync the memory before unmapping the entry
@@ -616,36 +632,37 @@ 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(&swiotlb->lock, flags);
{
count = ((index + nslots) < ALIGN(index + 1, IO_TLB_SEGSIZE) ?
- io_tlb_list[index + nslots] : 0);
+ swiotlb->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;
+ swiotlb->list[i] = ++count;
+ swiotlb->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;
+ for (i = index - 1; (OFFSET(i, IO_TLB_SEGSIZE) != IO_TLB_SEGSIZE -1) && swiotlb->list[i]; i--)
+ swiotlb->list[i] = ++count;

- io_tlb_used -= nslots;
+ swiotlb->used -= nslots;
}
- spin_unlock_irqrestore(&io_tlb_lock, flags);
+ spin_unlock_irqrestore(&swiotlb->lock, flags);
}

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];
+ struct swiotlb *swiotlb = &default_swiotlb;
+ int index = (tlb_addr - swiotlb->start) >> IO_TLB_SHIFT;
+ phys_addr_t orig_addr = swiotlb->orig_addr[index];

if (orig_addr == INVALID_PHYS_ADDR)
return;
@@ -713,31 +730,31 @@ 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 swiotlb->start points to
+ * physical address zero, swiotlb->end surely doesn't.
*/
- return io_tlb_end != 0;
+ return default_swiotlb.end != 0;
}

bool is_swiotlb_buffer(phys_addr_t paddr)
{
- return paddr >= io_tlb_start && paddr < io_tlb_end;
+ return paddr >= default_swiotlb.start && paddr < default_swiotlb.end;
}

phys_addr_t get_swiotlb_start(void)
{
- return io_tlb_start;
+ return default_swiotlb.start;
}

#ifdef CONFIG_DEBUG_FS

static int __init swiotlb_create_debugfs(void)
{
- struct dentry *root;
+ struct swiotlb *swiotlb = &default_swiotlb;

- 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);
+ swiotlb->debugfs = debugfs_create_dir("swiotlb", NULL);
+ debugfs_create_ulong("io_tlb_nslabs", 0400, swiotlb->debugfs, &swiotlb->nslabs);
+ debugfs_create_ulong("io_tlb_used", 0400, swiotlb->debugfs, &swiotlb->used);
return 0;
}

--
2.30.0.478.g8a0d178c01-goog