@@ -5904,8 +5904,10 @@
it if 0 is given (See Documentation/admin-guide/cgroup-v1/memory.rst)
swiotlb= [ARM,IA-64,PPC,MIPS,X86]
- Format: { <int> | force | noforce }
+ Format: { <int> [,<int>] | force | noforce }
<int> -- Number of I/O TLB slabs
+ <int> -- Second integer after comma. Number of swiotlb
+ areas with their own lock. Must be power of 2.
force -- force using of bounce buffers even if they
wouldn't be automatically used by the kernel
noforce -- Never use bounce buffers (for debugging)
@@ -62,6 +62,22 @@ dma_addr_t swiotlb_map(struct device *dev, phys_addr_t phys,
#ifdef CONFIG_SWIOTLB
extern enum swiotlb_force swiotlb_force;
+/**
+ * struct io_tlb_area - IO TLB memory area descriptor
+ *
+ * This is a single area with a single lock.
+ *
+ * @used: The number of used IO TLB block.
+ * @index: The slot index to start searching in this area for next round.
+ * @lock: The lock to protect the above data structures in the map and
+ * unmap calls.
+ */
+struct io_tlb_area {
+ unsigned long used;
+ unsigned int index;
+ spinlock_t lock;
+};
+
/**
* struct io_tlb_mem - IO TLB Memory Pool Descriptor
*
@@ -89,6 +105,8 @@ extern enum swiotlb_force swiotlb_force;
* @late_alloc: %true if allocated using the page allocator
* @force_bounce: %true if swiotlb bouncing is forced
* @for_alloc: %true if the pool is used for memory allocation
+ * @nareas: The area number in the pool.
+ * @area_nslabs: The slot number in the area.
*/
struct io_tlb_mem {
phys_addr_t start;
@@ -102,6 +120,9 @@ struct io_tlb_mem {
bool late_alloc;
bool force_bounce;
bool for_alloc;
+ unsigned int nareas;
+ unsigned int area_nslabs;
+ struct io_tlb_area *areas;
struct io_tlb_slot {
phys_addr_t orig_addr;
size_t alloc_size;
@@ -130,6 +151,7 @@ unsigned int swiotlb_max_segment(void);
size_t swiotlb_max_mapping_size(struct device *dev);
bool is_swiotlb_active(struct device *dev);
void __init swiotlb_adjust_size(unsigned long size);
+void __init swiotlb_adjust_nareas(unsigned int nareas);
#else
static inline void swiotlb_init(bool addressing_limited, unsigned int flags)
{
@@ -162,6 +184,11 @@ static inline bool is_swiotlb_active(struct device *dev)
static inline void swiotlb_adjust_size(unsigned long size)
{
}
+
+static inline void swiotlb_adjust_nareas(unsigned int nareas)
+{
+}
+
#endif /* CONFIG_SWIOTLB */
extern void swiotlb_print_info(void);
@@ -70,6 +70,7 @@ struct io_tlb_mem io_tlb_default_mem;
phys_addr_t swiotlb_unencrypted_base;
static unsigned long default_nslabs = IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIFT;
+static unsigned long default_nareas = 1;
static int __init
setup_io_tlb_npages(char *str)
@@ -79,6 +80,10 @@ setup_io_tlb_npages(char *str)
default_nslabs =
ALIGN(simple_strtoul(str, &str, 0), IO_TLB_SEGSIZE);
}
+ if (*str == ',')
+ ++str;
+ if (isdigit(*str))
+ swiotlb_adjust_nareas(simple_strtoul(str, &str, 0));
if (*str == ',')
++str;
if (!strcmp(str, "force"))
@@ -103,6 +108,28 @@ unsigned long swiotlb_size_or_default(void)
return default_nslabs << IO_TLB_SHIFT;
}
+void __init swiotlb_adjust_nareas(unsigned int nareas)
+{
+ if (!is_power_of_2(nareas)) {
+ pr_err("swiotlb: Invalid areas parameter %d.\n", nareas);
+ return;
+ }
+
+ default_nareas = nareas;
+
+ pr_info("area num %d.\n", nareas);
+ /*
+ * Round up number of slabs to the next power of 2.
+ * The last area is going be smaller than the rest if
+ * default_nslabs is not power of two.
+ */
+ if (nareas > 1) {
+ default_nslabs = roundup_pow_of_two(default_nslabs);
+ pr_info("SWIOTLB bounce buffer size roundup to %luMB",
+ (default_nslabs << IO_TLB_SHIFT) >> 20);
+ }
+}
+
void __init swiotlb_adjust_size(unsigned long size)
{
/*
@@ -112,8 +139,19 @@ void __init swiotlb_adjust_size(unsigned long size)
*/
if (default_nslabs != IO_TLB_DEFAULT_SIZE >> IO_TLB_SHIFT)
return;
+
+ /*
+ * Round up number of slabs to the next power of 2.
+ * The last area is going be smaller than the rest if
+ * default_nslabs is not power of two.
+ */
size = ALIGN(size, IO_TLB_SIZE);
default_nslabs = ALIGN(size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE);
+ if (default_nareas > 1) {
+ default_nslabs = roundup_pow_of_two(default_nslabs);
+ size = default_nslabs << IO_TLB_SHIFT;
+ }
+
pr_info("SWIOTLB bounce buffer size adjusted to %luMB", size >> 20);
}
@@ -192,7 +230,8 @@ void __init swiotlb_update_mem_attributes(void)
}
static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
- unsigned long nslabs, unsigned int flags, bool late_alloc)
+ unsigned long nslabs, unsigned int flags,
+ bool late_alloc, unsigned int nareas)
{
void *vaddr = phys_to_virt(start);
unsigned long bytes = nslabs << IO_TLB_SHIFT, i;
@@ -202,10 +241,17 @@ static void swiotlb_init_io_tlb_mem(struct io_tlb_mem *mem, phys_addr_t start,
mem->end = mem->start + bytes;
mem->index = 0;
mem->late_alloc = late_alloc;
+ mem->nareas = nareas;
+ mem->area_nslabs = nslabs / mem->nareas;
mem->force_bounce = swiotlb_force_bounce || (flags & SWIOTLB_FORCE);
spin_lock_init(&mem->lock);
+ for (i = 0; i < mem->nareas; i++) {
+ spin_lock_init(&mem->areas[i].lock);
+ mem->areas[i].index = 0;
+ }
+
for (i = 0; i < mem->nslabs; i++) {
mem->slots[i].list = IO_TLB_SEGSIZE - io_tlb_offset(i);
mem->slots[i].orig_addr = INVALID_PHYS_ADDR;
@@ -274,7 +320,13 @@ void __init swiotlb_init_remap(bool addressing_limit, unsigned int flags,
panic("%s: Failed to allocate %zu bytes align=0x%lx\n",
__func__, alloc_size, PAGE_SIZE);
- swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, flags, false);
+ mem->areas = memblock_alloc(sizeof(struct io_tlb_area) *
+ default_nareas, SMP_CACHE_BYTES);
+ if (!mem->areas)
+ panic("%s: Failed to allocate mem->areas.\n", __func__);
+
+ swiotlb_init_io_tlb_mem(mem, __pa(tlb), nslabs, flags,
+ false, default_nareas);
if (flags & SWIOTLB_VERBOSE)
swiotlb_print_info();
@@ -296,7 +348,7 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask,
struct io_tlb_mem *mem = &io_tlb_default_mem;
unsigned long nslabs = ALIGN(size >> IO_TLB_SHIFT, IO_TLB_SEGSIZE);
unsigned char *vstart = NULL;
- unsigned int order;
+ unsigned int order, area_order;
bool retried = false;
int rc = 0;
@@ -337,19 +389,31 @@ int swiotlb_init_late(size_t size, gfp_t gfp_mask,
(PAGE_SIZE << order) >> 20);
}
+ area_order = get_order(array_size(sizeof(*mem->areas),
+ default_nareas));
+ mem->areas = (struct io_tlb_area *)
+ __get_free_pages(GFP_KERNEL | __GFP_ZERO, area_order);
+ if (!mem->areas)
+ goto error_area;
+
mem->slots = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
get_order(array_size(sizeof(*mem->slots), nslabs)));
- if (!mem->slots) {
- free_pages((unsigned long)vstart, order);
- return -ENOMEM;
- }
+ if (!mem->slots)
+ goto error_slots;
set_memory_decrypted((unsigned long)vstart,
(nslabs << IO_TLB_SHIFT) >> PAGE_SHIFT);
- swiotlb_init_io_tlb_mem(mem, virt_to_phys(vstart), nslabs, 0, true);
+ swiotlb_init_io_tlb_mem(mem, virt_to_phys(vstart), nslabs, 0, true,
+ default_nareas);
swiotlb_print_info();
return 0;
+
+error_slots:
+ free_pages((unsigned long)mem->areas, area_order);
+error_area:
+ free_pages((unsigned long)vstart, order);
+ return -ENOMEM;
}
void __init swiotlb_exit(void)
@@ -357,6 +421,7 @@ void __init swiotlb_exit(void)
struct io_tlb_mem *mem = &io_tlb_default_mem;
unsigned long tbl_vaddr;
size_t tbl_size, slots_size;
+ unsigned int area_order;
if (swiotlb_force_bounce)
return;
@@ -371,9 +436,14 @@ void __init swiotlb_exit(void)
set_memory_encrypted(tbl_vaddr, tbl_size >> PAGE_SHIFT);
if (mem->late_alloc) {
+ area_order = get_order(array_size(sizeof(*mem->areas),
+ mem->nareas));
+ free_pages((unsigned long)mem->areas, area_order);
free_pages(tbl_vaddr, get_order(tbl_size));
free_pages((unsigned long)mem->slots, get_order(slots_size));
} else {
+ memblock_free_late(__pa(mem->areas),
+ mem->nareas * sizeof(struct io_tlb_area));
memblock_free_late(mem->start, tbl_size);
memblock_free_late(__pa(mem->slots), slots_size);
}
@@ -476,9 +546,9 @@ static inline unsigned long get_max_slots(unsigned long boundary_mask)
return nr_slots(boundary_mask + 1);
}
-static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
+static unsigned int wrap_area_index(struct io_tlb_mem *mem, unsigned int index)
{
- if (index >= mem->nslabs)
+ if (index >= mem->area_nslabs)
return 0;
return index;
}
@@ -487,10 +557,13 @@ static unsigned int wrap_index(struct io_tlb_mem *mem, unsigned int index)
* Find a suitable number of IO TLB entries size that will fit this request and
* allocate a buffer from that IO TLB pool.
*/
-static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
- size_t alloc_size, unsigned int alloc_align_mask)
+static int swiotlb_do_find_slots(struct io_tlb_mem *mem,
+ struct io_tlb_area *area,
+ int area_index,
+ struct device *dev, phys_addr_t orig_addr,
+ size_t alloc_size,
+ unsigned int alloc_align_mask)
{
- struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
unsigned long boundary_mask = dma_get_seg_boundary(dev);
dma_addr_t tbl_dma_addr =
phys_to_dma_unencrypted(dev, mem->start) & boundary_mask;
@@ -501,8 +574,11 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
unsigned int index, wrap, count = 0, i;
unsigned int offset = swiotlb_align_offset(dev, orig_addr);
unsigned long flags;
+ unsigned int slot_base;
+ unsigned int slot_index;
BUG_ON(!nslots);
+ BUG_ON(area_index >= mem->nareas);
/*
* For mappings with an alignment requirement don't bother looping to
@@ -514,16 +590,20 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
stride = max(stride, stride << (PAGE_SHIFT - IO_TLB_SHIFT));
stride = max(stride, (alloc_align_mask >> IO_TLB_SHIFT) + 1);
- spin_lock_irqsave(&mem->lock, flags);
- if (unlikely(nslots > mem->nslabs - mem->used))
+ spin_lock_irqsave(&area->lock, flags);
+ if (unlikely(nslots > mem->area_nslabs - area->used))
goto not_found;
- index = wrap = wrap_index(mem, ALIGN(mem->index, stride));
+ slot_base = area_index * mem->area_nslabs;
+ index = wrap = wrap_area_index(mem, ALIGN(area->index, stride));
+
do {
+ slot_index = slot_base + index;
+
if (orig_addr &&
- (slot_addr(tbl_dma_addr, index) & iotlb_align_mask) !=
- (orig_addr & iotlb_align_mask)) {
- index = wrap_index(mem, index + 1);
+ (slot_addr(tbl_dma_addr, slot_index) &
+ iotlb_align_mask) != (orig_addr & iotlb_align_mask)) {
+ index = wrap_area_index(mem, index + 1);
continue;
}
@@ -532,26 +612,26 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
* contiguous buffers, we allocate the buffers from that slot
* and mark the entries as '0' indicating unavailable.
*/
- if (!iommu_is_span_boundary(index, nslots,
+ if (!iommu_is_span_boundary(slot_index, nslots,
nr_slots(tbl_dma_addr),
max_slots)) {
- if (mem->slots[index].list >= nslots)
+ if (mem->slots[slot_index].list >= nslots)
goto found;
}
- index = wrap_index(mem, index + stride);
+ index = wrap_area_index(mem, index + stride);
} while (index != wrap);
not_found:
- spin_unlock_irqrestore(&mem->lock, flags);
+ spin_unlock_irqrestore(&area->lock, flags);
return -1;
found:
- for (i = index; i < index + nslots; i++) {
+ for (i = slot_index; i < slot_index + nslots; i++) {
mem->slots[i].list = 0;
mem->slots[i].alloc_size =
- alloc_size - (offset + ((i - index) << IO_TLB_SHIFT));
+ alloc_size - (offset + ((i - slot_index) << IO_TLB_SHIFT));
}
- for (i = index - 1;
+ for (i = slot_index - 1;
io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 &&
mem->slots[i].list; i--)
mem->slots[i].list = ++count;
@@ -559,14 +639,43 @@ static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
/*
* Update the indices to avoid searching in the next round.
*/
- if (index + nslots < mem->nslabs)
- mem->index = index + nslots;
+ if (index + nslots < mem->area_nslabs)
+ area->index = index + nslots;
else
- mem->index = 0;
- mem->used += nslots;
+ area->index = 0;
+ area->used += nslots;
+ spin_unlock_irqrestore(&area->lock, flags);
+ return slot_index;
+}
- spin_unlock_irqrestore(&mem->lock, flags);
- return index;
+static int swiotlb_find_slots(struct device *dev, phys_addr_t orig_addr,
+ size_t alloc_size, unsigned int alloc_align_mask)
+{
+ struct io_tlb_mem *mem = dev->dma_io_tlb_mem;
+ int start = raw_smp_processor_id() & ((1U << __fls(mem->nareas)) - 1);
+ int i = start, index;
+
+ do {
+ index = swiotlb_do_find_slots(mem, mem->areas + i, i,
+ dev, orig_addr, alloc_size,
+ alloc_align_mask);
+ if (index >= 0)
+ return index;
+ if (++i >= mem->nareas)
+ i = 0;
+ } while (i != start);
+
+ return -1;
+}
+
+static unsigned long mem_used(struct io_tlb_mem *mem)
+{
+ int i;
+ unsigned long used = 0;
+
+ for (i = 0; i < mem->nareas; i++)
+ used += mem->areas[i].used;
+ return used;
}
phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr,
@@ -598,7 +707,7 @@ 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, mem->nslabs, mem->used);
+ alloc_size, mem->nslabs, mem_used(mem));
return (phys_addr_t)DMA_MAPPING_ERROR;
}
@@ -628,6 +737,8 @@ static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr)
unsigned int offset = swiotlb_align_offset(dev, tlb_addr);
int index = (tlb_addr - offset - mem->start) >> IO_TLB_SHIFT;
int nslots = nr_slots(mem->slots[index].alloc_size + offset);
+ int aindex = index / mem->area_nslabs;
+ struct io_tlb_area *area = &mem->areas[aindex];
int count, i;
/*
@@ -636,7 +747,9 @@ static void swiotlb_release_slots(struct device *dev, 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(&mem->lock, flags);
+ BUG_ON(aindex >= mem->nareas);
+
+ spin_lock_irqsave(&area->lock, flags);
if (index + nslots < ALIGN(index + 1, IO_TLB_SEGSIZE))
count = mem->slots[index + nslots].list;
else
@@ -660,8 +773,8 @@ static void swiotlb_release_slots(struct device *dev, phys_addr_t tlb_addr)
io_tlb_offset(i) != IO_TLB_SEGSIZE - 1 && mem->slots[i].list;
i--)
mem->slots[i].list = ++count;
- mem->used -= nslots;
- spin_unlock_irqrestore(&mem->lock, flags);
+ area->used -= nslots;
+ spin_unlock_irqrestore(&area->lock, flags);
}
/*
@@ -759,12 +872,14 @@ EXPORT_SYMBOL_GPL(is_swiotlb_active);
static void swiotlb_create_debugfs_files(struct io_tlb_mem *mem,
const char *dirname)
{
+ unsigned long used = mem_used(mem);
+
mem->debugfs = debugfs_create_dir(dirname, io_tlb_default_mem.debugfs);
if (!mem->nslabs)
return;
debugfs_create_ulong("io_tlb_nslabs", 0400, mem->debugfs, &mem->nslabs);
- debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &mem->used);
+ debugfs_create_ulong("io_tlb_used", 0400, mem->debugfs, &used);
}
static int __init __maybe_unused swiotlb_create_default_debugfs(void)
@@ -815,6 +930,9 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
struct io_tlb_mem *mem = rmem->priv;
unsigned long nslabs = rmem->size >> IO_TLB_SHIFT;
+ /* Set Per-device io tlb area to one */
+ unsigned int nareas = 1;
+
/*
* Since multiple devices can share the same pool, the private data,
* io_tlb_mem struct, will be initialized by the first device attached
@@ -831,10 +949,18 @@ static int rmem_swiotlb_device_init(struct reserved_mem *rmem,
return -ENOMEM;
}
+ mem->areas = kcalloc(nareas, sizeof(*mem->areas),
+ GFP_KERNEL);
+ if (!mem->areas) {
+ kfree(mem);
+ kfree(mem->slots);
+ return -ENOMEM;
+ }
+
set_memory_decrypted((unsigned long)phys_to_virt(rmem->base),
rmem->size >> PAGE_SHIFT);
swiotlb_init_io_tlb_mem(mem, rmem->base, nslabs, SWIOTLB_FORCE,
- false);
+ false, nareas);
mem->for_alloc = true;
rmem->priv = mem;