From 61ca08c3220032dd88815b3465d56cb779258168 Mon Sep 17 00:00:00 2001 From: Alexander Duyck Date: Mon, 15 Oct 2012 10:19:44 -0700 Subject: [PATCH] swiotlb: Use physical addresses for swiotlb_tbl_unmap_single This change makes it so that the unmap functionality also uses physical addresses. This helps to further reduce the use of virt_to_phys and phys_to_virt functions. In order to clarify things since we now have 2 physical addresses in use inside of swiotlb_tbl_unmap_single I am renaming phys to orig_addr, and dma_addr to tlb_addr. This way is should be clear that orig_addr is contained within io_orig_addr and tlb_addr is an address within the io_tlb_addr buffer. Signed-off-by: Alexander Duyck Signed-off-by: Konrad Rzeszutek Wilk --- drivers/xen/swiotlb-xen.c | 4 ++-- include/linux/swiotlb.h | 3 ++- lib/swiotlb.c | 37 +++++++++++++++++++------------------ 3 files changed, 23 insertions(+), 21 deletions(-) diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c index 8a6035a..4cedc28 100644 --- a/drivers/xen/swiotlb-xen.c +++ b/drivers/xen/swiotlb-xen.c @@ -364,7 +364,7 @@ dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page, * Ensure that the address returned is DMA'ble */ if (!dma_capable(dev, dev_addr, size)) { - swiotlb_tbl_unmap_single(dev, phys_to_virt(map), size, dir); + swiotlb_tbl_unmap_single(dev, map, size, dir); dev_addr = 0; } return dev_addr; @@ -388,7 +388,7 @@ static void xen_unmap_single(struct device *hwdev, dma_addr_t dev_addr, /* NOTE: We use dev_addr here, not paddr! */ if (is_xen_swiotlb_buffer(dev_addr)) { - swiotlb_tbl_unmap_single(hwdev, phys_to_virt(paddr), size, dir); + swiotlb_tbl_unmap_single(hwdev, paddr, size, dir); return; } diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h index 1995f3e..291643c 100644 --- a/include/linux/swiotlb.h +++ b/include/linux/swiotlb.h @@ -43,7 +43,8 @@ extern phys_addr_t swiotlb_tbl_map_single(struct device *hwdev, phys_addr_t phys, size_t size, enum dma_data_direction dir); -extern void swiotlb_tbl_unmap_single(struct device *hwdev, char *dma_addr, +extern void swiotlb_tbl_unmap_single(struct device *hwdev, + phys_addr_t tlb_addr, size_t size, enum dma_data_direction dir); extern void swiotlb_tbl_sync_single(struct device *hwdev, char *dma_addr, diff --git a/lib/swiotlb.c b/lib/swiotlb.c index 3adc148..d7701dc 100644 --- a/lib/swiotlb.c +++ b/lib/swiotlb.c @@ -515,20 +515,20 @@ phys_addr_t map_single(struct device *hwdev, phys_addr_t phys, size_t size, /* * dma_addr is the kernel virtual address of the bounce buffer to unmap. */ -void -swiotlb_tbl_unmap_single(struct device *hwdev, char *dma_addr, size_t size, - enum dma_data_direction dir) +void swiotlb_tbl_unmap_single(struct device *hwdev, phys_addr_t tlb_addr, + size_t size, enum dma_data_direction dir) { unsigned long flags; int i, count, nslots = ALIGN(size, 1 << IO_TLB_SHIFT) >> IO_TLB_SHIFT; - int index = (dma_addr - (char *)phys_to_virt(io_tlb_start)) >> IO_TLB_SHIFT; - phys_addr_t phys = io_tlb_orig_addr[index]; + int index = (tlb_addr - io_tlb_start) >> IO_TLB_SHIFT; + phys_addr_t orig_addr = io_tlb_orig_addr[index]; /* * First, sync the memory before unmapping the entry */ if (phys && ((dir == DMA_FROM_DEVICE) || (dir == DMA_BIDIRECTIONAL))) - swiotlb_bounce(phys, dma_addr, size, DMA_FROM_DEVICE); + swiotlb_bounce(orig_addr, phys_to_virt(tlb_addr), + size, DMA_FROM_DEVICE); /* * Return the buffer to the free list by setting the corresponding @@ -621,17 +621,18 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size, ret = phys_to_virt(paddr); dev_addr = phys_to_dma(hwdev, paddr); - } - /* Confirm address can be DMA'd by device */ - if (dev_addr + size - 1 > dma_mask) { - printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", - (unsigned long long)dma_mask, - (unsigned long long)dev_addr); + /* Confirm address can be DMA'd by device */ + if (dev_addr + size - 1 > dma_mask) { + printk("hwdev DMA mask = 0x%016Lx, dev_addr = 0x%016Lx\n", + (unsigned long long)dma_mask, + (unsigned long long)dev_addr); - /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ - swiotlb_tbl_unmap_single(hwdev, ret, size, DMA_TO_DEVICE); - return NULL; + /* DMA_TO_DEVICE to avoid memcpy in unmap_single */ + swiotlb_tbl_unmap_single(hwdev, paddr, + size, DMA_TO_DEVICE); + return NULL; + } } *dma_handle = dev_addr; @@ -652,7 +653,7 @@ swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr, free_pages((unsigned long)vaddr, get_order(size)); else /* DMA_TO_DEVICE to avoid memcpy in swiotlb_tbl_unmap_single */ - swiotlb_tbl_unmap_single(hwdev, vaddr, size, DMA_TO_DEVICE); + swiotlb_tbl_unmap_single(hwdev, paddr, size, DMA_TO_DEVICE); } EXPORT_SYMBOL(swiotlb_free_coherent); @@ -716,7 +717,7 @@ dma_addr_t swiotlb_map_page(struct device *dev, struct page *page, /* Ensure that the address returned is DMA'ble */ if (!dma_capable(dev, dev_addr, size)) { - swiotlb_tbl_unmap_single(dev, phys_to_virt(map), size, dir); + swiotlb_tbl_unmap_single(dev, map, size, dir); return phys_to_dma(dev, io_tlb_overflow_buffer); } @@ -740,7 +741,7 @@ static void unmap_single(struct device *hwdev, dma_addr_t dev_addr, BUG_ON(dir == DMA_NONE); if (is_swiotlb_buffer(paddr)) { - swiotlb_tbl_unmap_single(hwdev, phys_to_virt(paddr), size, dir); + swiotlb_tbl_unmap_single(hwdev, paddr, size, dir); return; } -- 2.7.4