From cf14be0b41c659ede89abef3f7ec0e98e6cfea5b Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 6 Aug 2019 14:33:23 +0300 Subject: dma-direct: fix DMA_ATTR_NO_KERNEL_MAPPING The new DMA_ATTR_NO_KERNEL_MAPPING needs to actually assign a dma_addr to work. Also skip it if the architecture needs forced decryption handling, as that needs a kernel virtual address. Fixes: d98849aff879 (dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code) Signed-off-by: Christoph Hellwig Reviewed-by: Lucas Stach --- kernel/dma/direct.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 59bdceea3737..974e96a1de44 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -130,10 +130,12 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size, if (!page) return NULL; - if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { + if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && + !force_dma_unencrypted(dev)) { /* remove any dirty cache lines on the kernel alias */ if (!PageHighMem(page)) arch_dma_prep_coherent(page, size); + *dma_handle = phys_to_dma(dev, page_to_phys(page)); /* return the page pointer as the opaque cookie */ return page; } @@ -178,7 +180,8 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr, { unsigned int page_order = get_order(size); - if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) { + if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) && + !force_dma_unencrypted(dev)) { /* cpu_addr is a struct page cookie, not a kernel address */ __dma_direct_free_pages(dev, size, cpu_addr); return; -- cgit v1.2.3 From d8ad55538abe443919e20e0bb996561bca9cad84 Mon Sep 17 00:00:00 2001 From: Lucas Stach Date: Mon, 5 Aug 2019 17:51:53 +0200 Subject: dma-direct: don't truncate dma_required_mask to bus addressing capabilities The dma required_mask needs to reflect the actual addressing capabilities needed to handle the whole system RAM. When truncated down to the bus addressing capabilities dma_addressing_limited() will incorrectly signal no limitations for devices which are restricted by the bus_dma_mask. Fixes: b4ebe6063204 (dma-direct: implement complete bus_dma_mask handling) Signed-off-by: Lucas Stach Tested-by: Atish Patra Signed-off-by: Christoph Hellwig --- kernel/dma/direct.c | 3 --- 1 file changed, 3 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 974e96a1de44..795c9b095d75 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -47,9 +47,6 @@ u64 dma_direct_get_required_mask(struct device *dev) { u64 max_dma = phys_to_dma_direct(dev, (max_pfn - 1) << PAGE_SHIFT); - if (dev->bus_dma_mask && dev->bus_dma_mask < max_dma) - max_dma = dev->bus_dma_mask; - return (1ULL << (fls64(max_dma) - 1)) * 2 - 1; } -- cgit v1.2.3 From 33dcb37cef741294b481f4d889a465b8091f11bf Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Fri, 26 Jul 2019 09:26:40 +0200 Subject: dma-mapping: fix page attributes for dma_mmap_* All the way back to introducing dma_common_mmap we've defaulted to mark the pages as uncached. But this is wrong for DMA coherent devices. Later on DMA_ATTR_WRITE_COMBINE also got incorrect treatment as that flag is only treated special on the alloc side for non-coherent devices. Introduce a new dma_pgprot helper that deals with the check for coherent devices so that only the remapping cases ever reach arch_dma_mmap_pgprot and we thus ensure no aliasing of page attributes happens, which makes the powerpc version of arch_dma_mmap_pgprot obsolete and simplifies the remaining ones. Note that this means arch_dma_mmap_pgprot is a bit misnamed now, but we'll phase it out soon. Fixes: 64ccc9c033c6 ("common: dma-mapping: add support for generic dma_mmap_* calls") Reported-by: Shawn Anastasio Reported-by: Gavin Li Signed-off-by: Christoph Hellwig Acked-by: Catalin Marinas # arm64 --- kernel/dma/mapping.c | 19 ++++++++++++++++++- kernel/dma/remap.c | 2 +- 2 files changed, 19 insertions(+), 2 deletions(-) (limited to 'kernel') diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index b945239621d8..b0038ca3aa92 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -150,6 +150,23 @@ int dma_get_sgtable_attrs(struct device *dev, struct sg_table *sgt, } EXPORT_SYMBOL(dma_get_sgtable_attrs); +#ifdef CONFIG_MMU +/* + * Return the page attributes used for mapping dma_alloc_* memory, either in + * kernel space if remapping is needed, or to userspace through dma_mmap_*. + */ +pgprot_t dma_pgprot(struct device *dev, pgprot_t prot, unsigned long attrs) +{ + if (dev_is_dma_coherent(dev) || + (IS_ENABLED(CONFIG_DMA_NONCOHERENT_CACHE_SYNC) && + (attrs & DMA_ATTR_NON_CONSISTENT))) + return prot; + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_MMAP_PGPROT)) + return arch_dma_mmap_pgprot(dev, prot, attrs); + return pgprot_noncached(prot); +} +#endif /* CONFIG_MMU */ + /* * Create userspace mapping for the DMA-coherent memory. */ @@ -164,7 +181,7 @@ int dma_common_mmap(struct device *dev, struct vm_area_struct *vma, unsigned long pfn; int ret = -ENXIO; - vma->vm_page_prot = arch_dma_mmap_pgprot(dev, vma->vm_page_prot, attrs); + vma->vm_page_prot = dma_pgprot(dev, vma->vm_page_prot, attrs); if (dma_mmap_from_dev_coherent(dev, vma, cpu_addr, size, &ret)) return ret; diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c index a594aec07882..ffe78f0b2fe4 100644 --- a/kernel/dma/remap.c +++ b/kernel/dma/remap.c @@ -218,7 +218,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle, /* create a coherent mapping */ ret = dma_common_contiguous_remap(page, size, VM_USERMAP, - arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs), + dma_pgprot(dev, PAGE_KERNEL, attrs), __builtin_return_address(0)); if (!ret) { __dma_direct_free_pages(dev, size, page); -- cgit v1.2.3