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-rw-r--r--arch/arm/include/asm/dma-iommu.h8
-rw-r--r--arch/arm/mm/dma-mapping.c123
2 files changed, 110 insertions, 21 deletions
diff --git a/arch/arm/include/asm/dma-iommu.h b/arch/arm/include/asm/dma-iommu.h
index a8c56acc8c9..686797cf561 100644
--- a/arch/arm/include/asm/dma-iommu.h
+++ b/arch/arm/include/asm/dma-iommu.h
@@ -13,8 +13,12 @@ struct dma_iommu_mapping {
/* iommu specific data */
struct iommu_domain *domain;
- void *bitmap;
- size_t bits;
+ unsigned long **bitmaps; /* array of bitmaps */
+ unsigned int nr_bitmaps; /* nr of elements in array */
+ unsigned int extensions;
+ size_t bitmap_size; /* size of a single bitmap */
+ size_t bits; /* per bitmap */
+ unsigned int size; /* per bitmap */
unsigned int order;
dma_addr_t base;
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 11b3914660d..4d06295b8e3 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1069,6 +1069,8 @@ fs_initcall(dma_debug_do_init);
/* IOMMU */
+static int extend_iommu_mapping(struct dma_iommu_mapping *mapping);
+
static inline dma_addr_t __alloc_iova(struct dma_iommu_mapping *mapping,
size_t size)
{
@@ -1076,6 +1078,8 @@ static inline dma_addr_t __alloc_iova(struct dma_iommu_mapping *mapping,
unsigned int align = 0;
unsigned int count, start;
unsigned long flags;
+ dma_addr_t iova;
+ int i;
if (order > CONFIG_ARM_DMA_IOMMU_ALIGNMENT)
order = CONFIG_ARM_DMA_IOMMU_ALIGNMENT;
@@ -1087,30 +1091,78 @@ static inline dma_addr_t __alloc_iova(struct dma_iommu_mapping *mapping,
align = (1 << (order - mapping->order)) - 1;
spin_lock_irqsave(&mapping->lock, flags);
- start = bitmap_find_next_zero_area(mapping->bitmap, mapping->bits, 0,
- count, align);
- if (start > mapping->bits) {
- spin_unlock_irqrestore(&mapping->lock, flags);
- return DMA_ERROR_CODE;
+ for (i = 0; i < mapping->nr_bitmaps; i++) {
+ start = bitmap_find_next_zero_area(mapping->bitmaps[i],
+ mapping->bits, 0, count, align);
+
+ if (start > mapping->bits)
+ continue;
+
+ bitmap_set(mapping->bitmaps[i], start, count);
+ break;
}
- bitmap_set(mapping->bitmap, start, count);
+ /*
+ * No unused range found. Try to extend the existing mapping
+ * and perform a second attempt to reserve an IO virtual
+ * address range of size bytes.
+ */
+ if (i == mapping->nr_bitmaps) {
+ if (extend_iommu_mapping(mapping)) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return DMA_ERROR_CODE;
+ }
+
+ start = bitmap_find_next_zero_area(mapping->bitmaps[i],
+ mapping->bits, 0, count, align);
+
+ if (start > mapping->bits) {
+ spin_unlock_irqrestore(&mapping->lock, flags);
+ return DMA_ERROR_CODE;
+ }
+
+ bitmap_set(mapping->bitmaps[i], start, count);
+ }
spin_unlock_irqrestore(&mapping->lock, flags);
- return mapping->base + (start << (mapping->order + PAGE_SHIFT));
+ iova = mapping->base + (mapping->size * i);
+ iova += start << (mapping->order + PAGE_SHIFT);
+
+ return iova;
}
static inline void __free_iova(struct dma_iommu_mapping *mapping,
dma_addr_t addr, size_t size)
{
- unsigned int start = (addr - mapping->base) >>
- (mapping->order + PAGE_SHIFT);
- unsigned int count = ((size >> PAGE_SHIFT) +
- (1 << mapping->order) - 1) >> mapping->order;
+ unsigned int start, count;
unsigned long flags;
+ dma_addr_t bitmap_base;
+ u32 bitmap_index;
+
+ if (!size)
+ return;
+
+ bitmap_index = (u32) (addr - mapping->base) / (u32) mapping->size;
+ BUG_ON(addr < mapping->base || bitmap_index > mapping->extensions);
+
+ bitmap_base = mapping->base + mapping->size * bitmap_index;
+
+ start = (addr - bitmap_base) >> (mapping->order + PAGE_SHIFT);
+
+ if (addr + size > bitmap_base + mapping->size) {
+ /*
+ * The address range to be freed reaches into the iova
+ * range of the next bitmap. This should not happen as
+ * we don't allow this in __alloc_iova (at the
+ * moment).
+ */
+ BUG();
+ } else
+ count = ((size >> PAGE_SHIFT) +
+ (1 << mapping->order) - 1) >> mapping->order;
spin_lock_irqsave(&mapping->lock, flags);
- bitmap_clear(mapping->bitmap, start, count);
+ bitmap_clear(mapping->bitmaps[bitmap_index], start, count);
spin_unlock_irqrestore(&mapping->lock, flags);
}
@@ -1890,8 +1942,8 @@ arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
int order)
{
unsigned int count = size >> (PAGE_SHIFT + order);
- unsigned int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
struct dma_iommu_mapping *mapping;
+ int extensions = 0;
int err = -ENOMEM;
if (!count)
@@ -1901,23 +1953,35 @@ arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
if (!mapping)
goto err;
- mapping->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!mapping->bitmap)
+ mapping->bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
+ mapping->bitmaps = kzalloc((extensions + 1) * sizeof(unsigned long *),
+ GFP_KERNEL);
+ if (!mapping->bitmaps)
goto err2;
+ mapping->bitmaps[0] = kzalloc(mapping->bitmap_size, GFP_KERNEL);
+ if (!mapping->bitmaps[0])
+ goto err3;
+
+ mapping->nr_bitmaps = 1;
+ mapping->extensions = extensions;
mapping->base = base;
- mapping->bits = BITS_PER_BYTE * bitmap_size;
+ mapping->size = size;
mapping->order = order;
+ mapping->bits = BITS_PER_BYTE * mapping->bitmap_size;
+
spin_lock_init(&mapping->lock);
mapping->domain = iommu_domain_alloc(bus);
if (!mapping->domain)
- goto err3;
+ goto err4;
kref_init(&mapping->kref);
return mapping;
+err4:
+ kfree(mapping->bitmaps[0]);
err3:
- kfree(mapping->bitmap);
+ kfree(mapping->bitmaps);
err2:
kfree(mapping);
err:
@@ -1927,14 +1991,35 @@ EXPORT_SYMBOL_GPL(arm_iommu_create_mapping);
static void release_iommu_mapping(struct kref *kref)
{
+ int i;
struct dma_iommu_mapping *mapping =
container_of(kref, struct dma_iommu_mapping, kref);
iommu_domain_free(mapping->domain);
- kfree(mapping->bitmap);
+ for (i = 0; i < mapping->nr_bitmaps; i++)
+ kfree(mapping->bitmaps[i]);
+ kfree(mapping->bitmaps);
kfree(mapping);
}
+static int extend_iommu_mapping(struct dma_iommu_mapping *mapping)
+{
+ int next_bitmap;
+
+ if (mapping->nr_bitmaps > mapping->extensions)
+ return -EINVAL;
+
+ next_bitmap = mapping->nr_bitmaps;
+ mapping->bitmaps[next_bitmap] = kzalloc(mapping->bitmap_size,
+ GFP_ATOMIC);
+ if (!mapping->bitmaps[next_bitmap])
+ return -ENOMEM;
+
+ mapping->nr_bitmaps++;
+
+ return 0;
+}
+
void arm_iommu_release_mapping(struct dma_iommu_mapping *mapping)
{
if (mapping)
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-29 08:40:10 +0000