From 2a29e9f6b9b499f1fc5f4a48220dc3f4428499f9 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Wed, 3 Apr 2019 21:34:34 +0200 Subject: [PATCH] sparc64/pci_sun4v: fix ATU checks for large DMA masks Now that we allow drivers to always need to set larger than required DMA masks we need to be a little more careful in the sun4v PCI iommu driver to chose when to select the ATU support - a larger DMA mask can be set even when the platform does not support ATU, so we always have to check if it is avaiable before using it. Add a little helper for that and use it in all the places where we make ATU usage decisions based on the DMA mask. Fixes: 24132a419c68 ("sparc64/pci_sun4v: allow large DMA masks") Reported-by: Meelis Roos Signed-off-by: Christoph Hellwig Tested-by: Meelis Roos Acked-by: David S. Miller --- arch/sparc/kernel/pci_sun4v.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/arch/sparc/kernel/pci_sun4v.c b/arch/sparc/kernel/pci_sun4v.c index a8af6023c126..14b93c5564e3 100644 --- a/arch/sparc/kernel/pci_sun4v.c +++ b/arch/sparc/kernel/pci_sun4v.c @@ -73,6 +73,11 @@ static inline void iommu_batch_start(struct device *dev, unsigned long prot, uns p->npages = 0; } +static inline bool iommu_use_atu(struct iommu *iommu, u64 mask) +{ + return iommu->atu && mask > DMA_BIT_MASK(32); +} + /* Interrupts must be disabled. */ static long iommu_batch_flush(struct iommu_batch *p, u64 mask) { @@ -92,7 +97,7 @@ static long iommu_batch_flush(struct iommu_batch *p, u64 mask) prot &= (HV_PCI_MAP_ATTR_READ | HV_PCI_MAP_ATTR_WRITE); while (npages != 0) { - if (mask <= DMA_BIT_MASK(32) || !pbm->iommu->atu) { + if (!iommu_use_atu(pbm->iommu, mask)) { num = pci_sun4v_iommu_map(devhandle, HV_PCI_TSBID(0, entry), npages, @@ -179,7 +184,6 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, unsigned long flags, order, first_page, npages, n; unsigned long prot = 0; struct iommu *iommu; - struct atu *atu; struct iommu_map_table *tbl; struct page *page; void *ret; @@ -205,13 +209,11 @@ static void *dma_4v_alloc_coherent(struct device *dev, size_t size, memset((char *)first_page, 0, PAGE_SIZE << order); iommu = dev->archdata.iommu; - atu = iommu->atu; - mask = dev->coherent_dma_mask; - if (mask <= DMA_BIT_MASK(32) || !atu) + if (!iommu_use_atu(iommu, mask)) tbl = &iommu->tbl; else - tbl = &atu->tbl; + tbl = &iommu->atu->tbl; entry = iommu_tbl_range_alloc(dev, tbl, npages, NULL, (unsigned long)(-1), 0); @@ -333,7 +335,7 @@ static void dma_4v_free_coherent(struct device *dev, size_t size, void *cpu, atu = iommu->atu; devhandle = pbm->devhandle; - if (dvma <= DMA_BIT_MASK(32)) { + if (!iommu_use_atu(iommu, dvma)) { tbl = &iommu->tbl; iotsb_num = 0; /* we don't care for legacy iommu */ } else { @@ -374,7 +376,7 @@ static dma_addr_t dma_4v_map_page(struct device *dev, struct page *page, npages >>= IO_PAGE_SHIFT; mask = *dev->dma_mask; - if (mask <= DMA_BIT_MASK(32)) + if (!iommu_use_atu(iommu, mask)) tbl = &iommu->tbl; else tbl = &atu->tbl; @@ -510,7 +512,7 @@ static int dma_4v_map_sg(struct device *dev, struct scatterlist *sglist, IO_PAGE_SIZE) >> IO_PAGE_SHIFT; mask = *dev->dma_mask; - if (mask <= DMA_BIT_MASK(32)) + if (!iommu_use_atu(iommu, mask)) tbl = &iommu->tbl; else tbl = &atu->tbl; -- 2.11.0