| Message ID | 20190422175942.18788-21-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/26] arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable | expand |
On 22/04/2019 18:59, Christoph Hellwig wrote: > From: Robin Murphy <robin.murphy@arm.com> Honestly I don't think anything left of my patch here... > Apart from the iommu_dma_alloc_remap() case which remains sufficiently > different that it's better off being self-contained, the rest of the > logic can now be consolidated into a single flow which separates the > logcially-distinct steps of allocating pages, getting the CPU address, > and finally getting the IOMMU address. ...and it certainly doesn't do that any more. It's clear that we have fundamentally different ways of reading code, so I don't think it's productive to keep arguing personal preference - I still find the end result here a fair bit more tolerable than before, so if you update the commit message to reflect the actual change (at which point there's really nothing left of my authorship) I can live with it. Robin. > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > [hch: split the page allocation into a new helper to simplify the flow] > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/iommu/dma-iommu.c | 65 +++++++++++++++++++++------------------ > 1 file changed, 35 insertions(+), 30 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index 9b269f0792f3..acdfe866cb29 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -955,35 +955,14 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, > __iommu_dma_free(dev, size, cpu_addr); > } > > -static void *iommu_dma_alloc(struct device *dev, size_t size, > - dma_addr_t *handle, gfp_t gfp, unsigned long attrs) > +static void *iommu_dma_alloc_pages(struct device *dev, size_t size, > + struct page **pagep, gfp_t gfp, unsigned long attrs) > { > bool coherent = dev_is_dma_coherent(dev); > - int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); > size_t alloc_size = PAGE_ALIGN(size); > struct page *page = NULL; > void *cpu_addr; > > - gfp |= __GFP_ZERO; > - > - if (gfpflags_allow_blocking(gfp) && > - !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) > - return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); > - > - if (!gfpflags_allow_blocking(gfp) && !coherent) { > - cpu_addr = dma_alloc_from_pool(alloc_size, &page, gfp); > - if (!cpu_addr) > - return NULL; > - > - *handle = __iommu_dma_map(dev, page_to_phys(page), size, > - ioprot); > - if (*handle == DMA_MAPPING_ERROR) { > - dma_free_from_pool(cpu_addr, alloc_size); > - return NULL; > - } > - return cpu_addr; > - } > - > if (gfpflags_allow_blocking(gfp)) > page = dma_alloc_from_contiguous(dev, alloc_size >> PAGE_SHIFT, > get_order(alloc_size), > @@ -993,33 +972,59 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, > if (!page) > return NULL; > > - *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); > - if (*handle == DMA_MAPPING_ERROR) > - goto out_free_pages; > - > if (!coherent || PageHighMem(page)) { > pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); > > cpu_addr = dma_common_contiguous_remap(page, alloc_size, > VM_USERMAP, prot, __builtin_return_address(0)); > if (!cpu_addr) > - goto out_unmap; > + goto out_free_pages; > > if (!coherent) > arch_dma_prep_coherent(page, size); > } else { > cpu_addr = page_address(page); > } > + > + *pagep = page; > memset(cpu_addr, 0, alloc_size); > return cpu_addr; > -out_unmap: > - __iommu_dma_unmap(dev, *handle, size); > out_free_pages: > if (!dma_release_from_contiguous(dev, page, alloc_size >> PAGE_SHIFT)) > __free_pages(page, get_order(alloc_size)); > return NULL; > } > > +static void *iommu_dma_alloc(struct device *dev, size_t size, > + dma_addr_t *handle, gfp_t gfp, unsigned long attrs) > +{ > + bool coherent = dev_is_dma_coherent(dev); > + int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); > + struct page *page = NULL; > + void *cpu_addr; > + > + gfp |= __GFP_ZERO; > + > + if (gfpflags_allow_blocking(gfp) && > + !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) > + return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); > + > + if (!gfpflags_allow_blocking(gfp) && !coherent) > + cpu_addr = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp); > + else > + cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs); > + if (!cpu_addr) > + return NULL; > + > + *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); > + if (*handle == DMA_MAPPING_ERROR) { > + __iommu_dma_free(dev, size, cpu_addr); > + return NULL; > + } > + > + return cpu_addr; > +} > + > static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, > unsigned long pfn, size_t size) > { >
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index 9b269f0792f3..acdfe866cb29 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -955,35 +955,14 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, __iommu_dma_free(dev, size, cpu_addr); } -static void *iommu_dma_alloc(struct device *dev, size_t size, - dma_addr_t *handle, gfp_t gfp, unsigned long attrs) +static void *iommu_dma_alloc_pages(struct device *dev, size_t size, + struct page **pagep, gfp_t gfp, unsigned long attrs) { bool coherent = dev_is_dma_coherent(dev); - int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); size_t alloc_size = PAGE_ALIGN(size); struct page *page = NULL; void *cpu_addr; - gfp |= __GFP_ZERO; - - if (gfpflags_allow_blocking(gfp) && - !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) - return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); - - if (!gfpflags_allow_blocking(gfp) && !coherent) { - cpu_addr = dma_alloc_from_pool(alloc_size, &page, gfp); - if (!cpu_addr) - return NULL; - - *handle = __iommu_dma_map(dev, page_to_phys(page), size, - ioprot); - if (*handle == DMA_MAPPING_ERROR) { - dma_free_from_pool(cpu_addr, alloc_size); - return NULL; - } - return cpu_addr; - } - if (gfpflags_allow_blocking(gfp)) page = dma_alloc_from_contiguous(dev, alloc_size >> PAGE_SHIFT, get_order(alloc_size), @@ -993,33 +972,59 @@ static void *iommu_dma_alloc(struct device *dev, size_t size, if (!page) return NULL; - *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); - if (*handle == DMA_MAPPING_ERROR) - goto out_free_pages; - if (!coherent || PageHighMem(page)) { pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs); cpu_addr = dma_common_contiguous_remap(page, alloc_size, VM_USERMAP, prot, __builtin_return_address(0)); if (!cpu_addr) - goto out_unmap; + goto out_free_pages; if (!coherent) arch_dma_prep_coherent(page, size); } else { cpu_addr = page_address(page); } + + *pagep = page; memset(cpu_addr, 0, alloc_size); return cpu_addr; -out_unmap: - __iommu_dma_unmap(dev, *handle, size); out_free_pages: if (!dma_release_from_contiguous(dev, page, alloc_size >> PAGE_SHIFT)) __free_pages(page, get_order(alloc_size)); return NULL; } +static void *iommu_dma_alloc(struct device *dev, size_t size, + dma_addr_t *handle, gfp_t gfp, unsigned long attrs) +{ + bool coherent = dev_is_dma_coherent(dev); + int ioprot = dma_info_to_prot(DMA_BIDIRECTIONAL, coherent, attrs); + struct page *page = NULL; + void *cpu_addr; + + gfp |= __GFP_ZERO; + + if (gfpflags_allow_blocking(gfp) && + !(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) + return iommu_dma_alloc_remap(dev, size, handle, gfp, attrs); + + if (!gfpflags_allow_blocking(gfp) && !coherent) + cpu_addr = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp); + else + cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs); + if (!cpu_addr) + return NULL; + + *handle = __iommu_dma_map(dev, page_to_phys(page), size, ioprot); + if (*handle == DMA_MAPPING_ERROR) { + __iommu_dma_free(dev, size, cpu_addr); + return NULL; + } + + return cpu_addr; +} + static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, unsigned long pfn, size_t size) {