/* 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)
{
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;
- count = ((PAGE_ALIGN(size) >> PAGE_SHIFT) +
- (1 << mapping->order) - 1) >> mapping->order;
-
- if (order > mapping->order)
- align = (1 << (order - mapping->order)) - 1;
+ count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ align = (1 << 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 << 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) >> 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;
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);
}
* arm_iommu_create_mapping
* @bus: pointer to the bus holding the client device (for IOMMU calls)
* @base: start address of the valid IO address space
- * @size: size of the valid IO address space
- * @order: accuracy of the IO addresses allocations
+ * @size: maximum size of the valid IO address space
*
* Creates a mapping structure which holds information about used/unused
* IO address ranges, which is required to perform memory allocation and
* arm_iommu_attach_device function.
*/
struct dma_iommu_mapping *
-arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size,
- int order)
+arm_iommu_create_mapping(struct bus_type *bus, dma_addr_t base, size_t size)
{
- unsigned int count = size >> (PAGE_SHIFT + order);
- unsigned int bitmap_size = BITS_TO_LONGS(count) * sizeof(long);
+ unsigned int bits = size >> PAGE_SHIFT;
+ unsigned int bitmap_size = BITS_TO_LONGS(bits) * sizeof(long);
struct dma_iommu_mapping *mapping;
+ int extensions = 1;
int err = -ENOMEM;
- if (!count)
+ if (!bitmap_size)
return ERR_PTR(-EINVAL);
+ if (bitmap_size > PAGE_SIZE) {
+ extensions = bitmap_size / PAGE_SIZE;
+ bitmap_size = PAGE_SIZE;
+ }
+
mapping = kzalloc(sizeof(struct dma_iommu_mapping), GFP_KERNEL);
if (!mapping)
goto err;
- mapping->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!mapping->bitmap)
+ mapping->bitmap_size = bitmap_size;
+ mapping->bitmaps = kzalloc(extensions * sizeof(unsigned long *),
+ GFP_KERNEL);
+ if (!mapping->bitmaps)
goto err2;
+ mapping->bitmaps[0] = kzalloc(bitmap_size, GFP_KERNEL);
+ if (!mapping->bitmaps[0])
+ goto err3;
+
+ mapping->nr_bitmaps = 1;
+ mapping->extensions = extensions;
mapping->base = base;
+ mapping->size = bitmap_size << PAGE_SHIFT;
mapping->bits = BITS_PER_BYTE * bitmap_size;
- mapping->order = order;
+
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:
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)
projects / firefly-linux-kernel-4.4.55.git / blobdiff