dma-direct: exclude dma_direct_map_resource from the min_low_pfn check

The valid memory address check in dma_capable only makes sense when mapping
normal memory, not when using dma_map_resource to map a device resource.
Add a new boolean argument to dma_capable to exclude that check for the
dma_map_resource case.

Fixes: b12d66278dd6 ("dma-direct: check for overflows on 32 bit DMA addresses")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>

diff --git a/arch/x86/kernel/amd_gart_64.c b/arch/x86/kernel/amd_gart_64.c
index a6ac3712db8bcc4afbe1e61273121e289b9627a1..5cfab41e8509c6a77ae277f0be15432300c88f8f 100644 (file)
--- a/arch/x86/kernel/amd_gart_64.c
+++ b/arch/x86/kernel/amd_gart_64.c
@@ -185,13 +185,13 @@ static void iommu_full(struct device *dev, size_t size, int dir)
 static inline int
 need_iommu(struct device *dev, unsigned long addr, size_t size)
 {
-       return force_iommu || !dma_capable(dev, addr, size);
+       return force_iommu || !dma_capable(dev, addr, size, true);
 }
 
 static inline int
 nonforced_iommu(struct device *dev, unsigned long addr, size_t size)
 {
-       return !dma_capable(dev, addr, size);
+       return !dma_capable(dev, addr, size, true);
 }
 
 /* Map a single continuous physical area into the IOMMU.

diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 3f8b2cdb4acb030e8de2f31dc45b6b887b56a9e5..b6d27762c6f8cc35ff698ae96005100d55748206 100644 (file)
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -375,7 +375,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
         * we can safely return the device addr and not worry about bounce
         * buffering it.
         */
-       if (dma_capable(dev, dev_addr, size) &&
+       if (dma_capable(dev, dev_addr, size, true) &&
            !range_straddles_page_boundary(phys, size) &&
                !xen_arch_need_swiotlb(dev, phys, dev_addr) &&
                swiotlb_force != SWIOTLB_FORCE)
@@ -397,7 +397,7 @@ static dma_addr_t xen_swiotlb_map_page(struct device *dev, struct page *page,
        /*
         * Ensure that the address returned is DMA'ble
         */
-       if (unlikely(!dma_capable(dev, dev_addr, size))) {
+       if (unlikely(!dma_capable(dev, dev_addr, size, true))) {
                swiotlb_tbl_unmap_single(dev, map, size, size, dir,
                                attrs | DMA_ATTR_SKIP_CPU_SYNC);
                return DMA_MAPPING_ERROR;

diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index f8959f75e496e245c0855f24774859aebfcd63b1..99b77dd5f79b9f8de57e9ef40840cc01caf4fd03 100644 (file)
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -49,14 +49,15 @@ static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr)
        return __sme_clr(__dma_to_phys(dev, daddr));
 }
 
-static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
+               bool is_ram)
 {
        dma_addr_t end = addr + size - 1;
 
        if (!dev->dma_mask)
                return false;
 
-       if (!IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
+       if (is_ram && !IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
            min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))
                return false;
 

diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index a479bd2d1e8b1e0ad2512fb6ade62c361bd2b0e2..40f1f0aac4b1d0d096516b643fe8bfde480cbd81 100644 (file)
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -363,7 +363,7 @@ static inline bool dma_direct_possible(struct device *dev, dma_addr_t dma_addr,
                size_t size)
 {
        return swiotlb_force != SWIOTLB_FORCE &&
-               dma_capable(dev, dma_addr, size);
+               dma_capable(dev, dma_addr, size, true);
 }
 
 dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
@@ -412,7 +412,7 @@ dma_addr_t dma_direct_map_resource(struct device *dev, phys_addr_t paddr,
 {
        dma_addr_t dma_addr = paddr;
 
-       if (unlikely(!dma_capable(dev, dma_addr, size))) {
+       if (unlikely(!dma_capable(dev, dma_addr, size, false))) {
                report_addr(dev, dma_addr, size);
                return DMA_MAPPING_ERROR;
        }

diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c
index 673a2cdb2656b01ada63b12cd62d30a91b9aaa79..9280d6f8271ed4360bab41cfb2d8dc66d75ca203 100644 (file)
--- a/kernel/dma/swiotlb.c
+++ b/kernel/dma/swiotlb.c
@@ -678,7 +678,7 @@ bool swiotlb_map(struct device *dev, phys_addr_t *phys, dma_addr_t *dma_addr,
 
        /* Ensure that the address returned is DMA'ble */
        *dma_addr = __phys_to_dma(dev, *phys);
-       if (unlikely(!dma_capable(dev, *dma_addr, size))) {
+       if (unlikely(!dma_capable(dev, *dma_addr, size, true))) {
                swiotlb_tbl_unmap_single(dev, *phys, size, size, dir,
                        attrs | DMA_ATTR_SKIP_CPU_SYNC);
                return false;