| Message ID | 20190327080448.5500-9-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/21] arm64/iommu: handle non-remapped addresses in ->mmap and ->get_sgtable | expand |
On 27/03/2019 08:04, Christoph Hellwig wrote: > Move the vm_area handling into __iommu_dma_mmap, which is renamed > to iommu_dma_mmap_remap. > > Inline __iommu_dma_mmap_pfn into the main function to simplify the code > flow a bit. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/iommu/dma-iommu.c | 50 ++++++++++++++------------------------- > 1 file changed, 18 insertions(+), 32 deletions(-) > > diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c > index d14fe9f8c692..43bd3c7e0f6b 100644 > --- a/drivers/iommu/dma-iommu.c > +++ b/drivers/iommu/dma-iommu.c > @@ -597,23 +597,27 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, > } > > /** > - * __iommu_dma_mmap - Map a buffer into provided user VMA > - * @pages: Array representing buffer from __iommu_dma_alloc() > + * iommu_dma_mmap_remap - Map a remapped page array into provided user VMA > + * @cpu_addr: virtual address of the memory to be remapped > * @size: Size of buffer in bytes > * @vma: VMA describing requested userspace mapping > * > - * Maps the pages of the buffer in @pages into @vma. The caller is responsible > + * Maps the pages pointed to by @cpu_addr into @vma. The caller is responsible > * for verifying the correct size and protection of @vma beforehand. > */ > -static int __iommu_dma_mmap(struct page **pages, size_t size, > +static int iommu_dma_mmap_remap(void *cpu_addr, size_t size, > struct vm_area_struct *vma) > { > + struct vm_struct *area = find_vm_area(cpu_addr); > unsigned long uaddr = vma->vm_start; > unsigned int i, count = PAGE_ALIGN(size) >> PAGE_SHIFT; > int ret = -ENXIO; > > + if (WARN_ON(!area || !area->pages)) > + return -ENXIO; > + > for (i = vma->vm_pgoff; i < count && uaddr < vma->vm_end; i++) { > - ret = vm_insert_page(vma, uaddr, pages[i]); > + ret = vm_insert_page(vma, uaddr, area->pages[i]); > if (ret) > break; > uaddr += PAGE_SIZE; > @@ -1052,21 +1056,13 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, > } > } > > -static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, > - unsigned long pfn, size_t size) > -{ > - return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, > - vma->vm_end - vma->vm_start, > - vma->vm_page_prot); > -} > - > static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, > void *cpu_addr, dma_addr_t dma_addr, size_t size, > unsigned long attrs) > { > unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; > unsigned long off = vma->vm_pgoff; > - struct vm_struct *area; > + unsigned long pfn; > int ret; > > vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs); > @@ -1077,25 +1073,15 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, > if (off >= nr_pages || vma_pages(vma) > nr_pages - off) > return -ENXIO; > > - if (!is_vmalloc_addr(cpu_addr)) { > - unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); > - return __iommu_dma_mmap_pfn(vma, pfn, size); > - } > + if (is_vmalloc_addr(cpu_addr)) { > + if (!(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) > + return iommu_dma_mmap_remap(cpu_addr, size, vma); > + pfn = vmalloc_to_pfn(cpu_addr); > + } else > + pfn = page_to_pfn(virt_to_page(cpu_addr)); Nit: braces around the else clause for correct style. Otherwise, this seems to make sense; Reviewed-by: Robin Murphy <robin.murphy@arm.com> > > - if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) { > - /* > - * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped, > - * hence in the vmalloc space. > - */ > - unsigned long pfn = vmalloc_to_pfn(cpu_addr); > - return __iommu_dma_mmap_pfn(vma, pfn, size); > - } > - > - area = find_vm_area(cpu_addr); > - if (WARN_ON(!area || !area->pages)) > - return -ENXIO; > - > - return __iommu_dma_mmap(area->pages, size, vma); > + return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, > + vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot); > } > > static int __iommu_dma_get_sgtable_page(struct sg_table *sgt, struct page *page, >
On Tue, Apr 09, 2019 at 04:29:07PM +0100, Robin Murphy wrote: > On 27/03/2019 08:04, Christoph Hellwig wrote: >> Move the vm_area handling into __iommu_dma_mmap, which is renamed >> to iommu_dma_mmap_remap. >> >> Inline __iommu_dma_mmap_pfn into the main function to simplify the code >> flow a bit. >> >> Signed-off-by: Christoph Hellwig <hch@lst.de> >> --- >> drivers/iommu/dma-iommu.c | 50 ++++++++++++++------------------------- >> 1 file changed, 18 insertions(+), 32 deletions(-) >> >> diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c >> index d14fe9f8c692..43bd3c7e0f6b 100644 >> --- a/drivers/iommu/dma-iommu.c >> +++ b/drivers/iommu/dma-iommu.c >> @@ -597,23 +597,27 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, >> } >> /** >> - * __iommu_dma_mmap - Map a buffer into provided user VMA >> - * @pages: Array representing buffer from __iommu_dma_alloc() >> + * iommu_dma_mmap_remap - Map a remapped page array into provided user VMA >> + * @cpu_addr: virtual address of the memory to be remapped >> * @size: Size of buffer in bytes >> * @vma: VMA describing requested userspace mapping >> * >> - * Maps the pages of the buffer in @pages into @vma. The caller is responsible >> + * Maps the pages pointed to by @cpu_addr into @vma. The caller is responsible >> * for verifying the correct size and protection of @vma beforehand. >> */ >> -static int __iommu_dma_mmap(struct page **pages, size_t size, >> +static int iommu_dma_mmap_remap(void *cpu_addr, size_t size, >> struct vm_area_struct *vma) >> { >> + struct vm_struct *area = find_vm_area(cpu_addr); >> unsigned long uaddr = vma->vm_start; >> unsigned int i, count = PAGE_ALIGN(size) >> PAGE_SHIFT; >> int ret = -ENXIO; >> + if (WARN_ON(!area || !area->pages)) >> + return -ENXIO; >> + >> for (i = vma->vm_pgoff; i < count && uaddr < vma->vm_end; i++) { >> - ret = vm_insert_page(vma, uaddr, pages[i]); >> + ret = vm_insert_page(vma, uaddr, area->pages[i]); >> if (ret) >> break; >> uaddr += PAGE_SIZE; >> @@ -1052,21 +1056,13 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, >> } >> } >> -static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, >> - unsigned long pfn, size_t size) >> -{ >> - return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, >> - vma->vm_end - vma->vm_start, >> - vma->vm_page_prot); >> -} >> - >> static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, >> void *cpu_addr, dma_addr_t dma_addr, size_t size, >> unsigned long attrs) >> { >> unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; >> unsigned long off = vma->vm_pgoff; >> - struct vm_struct *area; >> + unsigned long pfn; >> int ret; >> vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, >> attrs); >> @@ -1077,25 +1073,15 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, >> if (off >= nr_pages || vma_pages(vma) > nr_pages - off) >> return -ENXIO; >> - if (!is_vmalloc_addr(cpu_addr)) { >> - unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); >> - return __iommu_dma_mmap_pfn(vma, pfn, size); >> - } >> + if (is_vmalloc_addr(cpu_addr)) { >> + if (!(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) >> + return iommu_dma_mmap_remap(cpu_addr, size, vma); >> + pfn = vmalloc_to_pfn(cpu_addr); >> + } else >> + pfn = page_to_pfn(virt_to_page(cpu_addr)); > > Nit: braces around the else clause for correct style. So I generally prefer that style too. But in this case one of the later patches will add an ifdef around the if { ... } else, and adding braces would make that a lot more awkware. There is another occurance or two of this patter in this series elsewhere as well.
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c index d14fe9f8c692..43bd3c7e0f6b 100644 --- a/drivers/iommu/dma-iommu.c +++ b/drivers/iommu/dma-iommu.c @@ -597,23 +597,27 @@ static struct page **__iommu_dma_alloc(struct device *dev, size_t size, } /** - * __iommu_dma_mmap - Map a buffer into provided user VMA - * @pages: Array representing buffer from __iommu_dma_alloc() + * iommu_dma_mmap_remap - Map a remapped page array into provided user VMA + * @cpu_addr: virtual address of the memory to be remapped * @size: Size of buffer in bytes * @vma: VMA describing requested userspace mapping * - * Maps the pages of the buffer in @pages into @vma. The caller is responsible + * Maps the pages pointed to by @cpu_addr into @vma. The caller is responsible * for verifying the correct size and protection of @vma beforehand. */ -static int __iommu_dma_mmap(struct page **pages, size_t size, +static int iommu_dma_mmap_remap(void *cpu_addr, size_t size, struct vm_area_struct *vma) { + struct vm_struct *area = find_vm_area(cpu_addr); unsigned long uaddr = vma->vm_start; unsigned int i, count = PAGE_ALIGN(size) >> PAGE_SHIFT; int ret = -ENXIO; + if (WARN_ON(!area || !area->pages)) + return -ENXIO; + for (i = vma->vm_pgoff; i < count && uaddr < vma->vm_end; i++) { - ret = vm_insert_page(vma, uaddr, pages[i]); + ret = vm_insert_page(vma, uaddr, area->pages[i]); if (ret) break; uaddr += PAGE_SIZE; @@ -1052,21 +1056,13 @@ static void iommu_dma_free(struct device *dev, size_t size, void *cpu_addr, } } -static int __iommu_dma_mmap_pfn(struct vm_area_struct *vma, - unsigned long pfn, size_t size) -{ - return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, - vma->vm_end - vma->vm_start, - vma->vm_page_prot); -} - static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs) { unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long off = vma->vm_pgoff; - struct vm_struct *area; + unsigned long pfn; int ret; vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs); @@ -1077,25 +1073,15 @@ static int iommu_dma_mmap(struct device *dev, struct vm_area_struct *vma, if (off >= nr_pages || vma_pages(vma) > nr_pages - off) return -ENXIO; - if (!is_vmalloc_addr(cpu_addr)) { - unsigned long pfn = page_to_pfn(virt_to_page(cpu_addr)); - return __iommu_dma_mmap_pfn(vma, pfn, size); - } + if (is_vmalloc_addr(cpu_addr)) { + if (!(attrs & DMA_ATTR_FORCE_CONTIGUOUS)) + return iommu_dma_mmap_remap(cpu_addr, size, vma); + pfn = vmalloc_to_pfn(cpu_addr); + } else + pfn = page_to_pfn(virt_to_page(cpu_addr)); - if (attrs & DMA_ATTR_FORCE_CONTIGUOUS) { - /* - * DMA_ATTR_FORCE_CONTIGUOUS allocations are always remapped, - * hence in the vmalloc space. - */ - unsigned long pfn = vmalloc_to_pfn(cpu_addr); - return __iommu_dma_mmap_pfn(vma, pfn, size); - } - - area = find_vm_area(cpu_addr); - if (WARN_ON(!area || !area->pages)) - return -ENXIO; - - return __iommu_dma_mmap(area->pages, size, vma); + return remap_pfn_range(vma, vma->vm_start, pfn + vma->vm_pgoff, + vma_pages(vma) << PAGE_SHIFT, vma->vm_page_prot); } static int __iommu_dma_get_sgtable_page(struct sg_table *sgt, struct page *page,
Move the vm_area handling into __iommu_dma_mmap, which is renamed to iommu_dma_mmap_remap. Inline __iommu_dma_mmap_pfn into the main function to simplify the code flow a bit. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/iommu/dma-iommu.c | 50 ++++++++++++++------------------------- 1 file changed, 18 insertions(+), 32 deletions(-)