diff options
Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r-- | arch/arm/mm/dma-mapping.c | 123 |
1 files changed, 104 insertions, 19 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 11b3914660d2..4d06295b8e3e 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) |