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*参照元 [#e2a44181] #backlinks *説明 [#fa621326] -パス: 複数あり --ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY 有効: [[linux-4.4.1/drivers/base/dma-coherent.c]] --ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY 無効: [[linux-4.4.1/include/asm-generic/dma-coherent.h]] --[[linux-4.4.1/ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY]] -FIXME: これは何？ --説明 **引数 [#b2ae27d2] -struct device *dev -- --[[linux-4.4.1/device]] -int order -- -void *vaddr -- **返り値 [#l7f3b135] -int -- **参考 [#zf36cceb] *実装 [#g09fff9e] **ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY 有効: drivers/base/dma-coherent.c [#c1521458] /** * dma_release_from_coherent() - try to free the memory allocated from per-device coherent memory pool * @dev: device from which the memory was allocated * @order: the order of pages allocated * @vaddr: virtual address of allocated pages * * This checks whether the memory was allocated from the per-device * coherent memory pool and if so, releases that memory. * * Returns 1 if we correctly released the memory, or 0 if * dma_release_coherent() should proceed with releasing memory from * generic pools. */ int dma_release_from_coherent(struct device *dev, int order, void *vaddr) { struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; - --[[linux-4.4.1/dma_coherent_mem]] if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) { int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; unsigned long flags; - --[[linux-4.4.1/PAGE_SHIFT]] spin_lock_irqsave(&mem->spinlock, flags); bitmap_release_region(mem->bitmap, page, order); spin_unlock_irqrestore(&mem->spinlock, flags); - --[[linux-4.4.1/spin_lock_irqsave()]] --[[linux-4.4.1/bitmap_release_region()]] --[[linux-4.4.1/spin_unlock_irqrestore()]] return 1; } return 0; } EXPORT_SYMBOL(dma_release_from_coherent); - --[[linux-4.4.1/EXPORT_SYMBOL()]] **ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY 無効: include/asm-generic/dma-coherent.h [#j2e4ae49] #define dma_release_from_coherent(dev, order, vaddr) (0) -常に失敗する。 *コメント [#sd068db5]
