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author | Joerg Roedel <jroedel@suse.de> | 2016-07-06 17:20:54 +0200 |
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committer | Joerg Roedel <jroedel@suse.de> | 2016-07-14 10:21:07 +0200 |
commit | 80187fd39dcb30e3aa39e93a87b2d2f7fc8f4fd5 (patch) | |
tree | 8efcd199576a65d4152360fbfa0668f502253f25 /drivers/iommu | |
parent | iommu/amd: Introduce dir2prot() helper (diff) | |
download | linux-80187fd39dcb30e3aa39e93a87b2d2f7fc8f4fd5.tar.xz linux-80187fd39dcb30e3aa39e93a87b2d2f7fc8f4fd5.zip |
iommu/amd: Optimize map_sg and unmap_sg
Optimize these functions so that they need only one call
into the address alloctor. This also saves a couple of
io-tlb flushes in the unmap_sg path.
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Diffstat (limited to 'drivers/iommu')
-rw-r--r-- | drivers/iommu/amd_iommu.c | 111 |
1 files changed, 85 insertions, 26 deletions
diff --git a/drivers/iommu/amd_iommu.c b/drivers/iommu/amd_iommu.c index 281cacbd5816..acad37c3f0a1 100644 --- a/drivers/iommu/amd_iommu.c +++ b/drivers/iommu/amd_iommu.c @@ -2396,50 +2396,110 @@ static void unmap_page(struct device *dev, dma_addr_t dma_addr, size_t size, __unmap_single(domain->priv, dma_addr, size, dir); } +static int sg_num_pages(struct device *dev, + struct scatterlist *sglist, + int nelems) +{ + unsigned long mask, boundary_size; + struct scatterlist *s; + int i, npages = 0; + + mask = dma_get_seg_boundary(dev); + boundary_size = mask + 1 ? ALIGN(mask + 1, PAGE_SIZE) >> PAGE_SHIFT : + 1UL << (BITS_PER_LONG - PAGE_SHIFT); + + for_each_sg(sglist, s, nelems, i) { + int p, n; + + s->dma_address = npages << PAGE_SHIFT; + p = npages % boundary_size; + n = iommu_num_pages(sg_phys(s), s->length, PAGE_SIZE); + if (p + n > boundary_size) + npages += boundary_size - p; + npages += n; + } + + return npages; +} + /* * The exported map_sg function for dma_ops (handles scatter-gather * lists). */ static int map_sg(struct device *dev, struct scatterlist *sglist, - int nelems, enum dma_data_direction dir, + int nelems, enum dma_data_direction direction, struct dma_attrs *attrs) { + int mapped_pages = 0, npages = 0, prot = 0, i; struct protection_domain *domain; - int i; + struct dma_ops_domain *dma_dom; struct scatterlist *s; - phys_addr_t paddr; - int mapped_elems = 0; + unsigned long address; u64 dma_mask; domain = get_domain(dev); if (IS_ERR(domain)) return 0; + dma_dom = domain->priv; dma_mask = *dev->dma_mask; + npages = sg_num_pages(dev, sglist, nelems); + + address = dma_ops_alloc_iova(dev, dma_dom, npages, dma_mask); + if (address == DMA_ERROR_CODE) + goto out_err; + + prot = dir2prot(direction); + + /* Map all sg entries */ for_each_sg(sglist, s, nelems, i) { - paddr = sg_phys(s); + int j, pages = iommu_num_pages(sg_phys(s), s->length, PAGE_SIZE); + + for (j = 0; j < pages; ++j) { + unsigned long bus_addr, phys_addr; + int ret; - s->dma_address = __map_single(dev, domain->priv, - paddr, s->length, dir, dma_mask); + bus_addr = address + s->dma_address + (j << PAGE_SHIFT); + phys_addr = (sg_phys(s) & PAGE_MASK) + (j << PAGE_SHIFT); + ret = iommu_map_page(domain, bus_addr, phys_addr, PAGE_SIZE, prot, GFP_ATOMIC); + if (ret) + goto out_unmap; - if (s->dma_address) { - s->dma_length = s->length; - mapped_elems++; - } else - goto unmap; + mapped_pages += 1; + } } - return mapped_elems; + /* Everything is mapped - write the right values into s->dma_address */ + for_each_sg(sglist, s, nelems, i) { + s->dma_address += address + s->offset; + s->dma_length = s->length; + } + + return nelems; + +out_unmap: + pr_err("%s: IOMMU mapping error in map_sg (io-pages: %d)\n", + dev_name(dev), npages); + + for_each_sg(sglist, s, nelems, i) { + int j, pages = iommu_num_pages(sg_phys(s), s->length, PAGE_SIZE); + + for (j = 0; j < pages; ++j) { + unsigned long bus_addr; -unmap: - for_each_sg(sglist, s, mapped_elems, i) { - if (s->dma_address) - __unmap_single(domain->priv, s->dma_address, - s->dma_length, dir); - s->dma_address = s->dma_length = 0; + bus_addr = address + s->dma_address + (j << PAGE_SHIFT); + iommu_unmap_page(domain, bus_addr, PAGE_SIZE); + + if (--mapped_pages) + goto out_free_iova; + } } +out_free_iova: + free_iova_fast(&dma_dom->iovad, address, npages); + +out_err: return 0; } @@ -2452,18 +2512,17 @@ static void unmap_sg(struct device *dev, struct scatterlist *sglist, struct dma_attrs *attrs) { struct protection_domain *domain; - struct scatterlist *s; - int i; + unsigned long startaddr; + int npages = 2; domain = get_domain(dev); if (IS_ERR(domain)) return; - for_each_sg(sglist, s, nelems, i) { - __unmap_single(domain->priv, s->dma_address, - s->dma_length, dir); - s->dma_address = s->dma_length = 0; - } + startaddr = sg_dma_address(sglist) & PAGE_MASK; + npages = sg_num_pages(dev, sglist, nelems); + + __unmap_single(domain->priv, startaddr, npages << PAGE_SHIFT, dir); } /* |