Control: tag -1 patch For future reference, these are the patches reported to fix this, although they don't actually apply to the current jessie branch. Ben. -- Ben Hutchings The generation of random numbers is too important to be left to chance. - Robert Coveyou
From 7648f3da0d79feb1e9932c309f5e87ff7f100fc5 Mon Sep 17 00:00:00 2001
From: David Vrabel <david.vrabel@citrix.com>
Date: Fri, 9 May 2014 11:30:31 +0100
Subject: [PATCH 1/2] dma: add dma_get_required_mask_from_max_pfn()
ia64 provides a duplicate of the generic dma_get_required_mask()
because it has ARCH_HAS_GET_REQUIRED_MASK. Provide a common
dma_get_require_mask_max_pfn() instead.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: linux-ia64@vger.kernel.org
diff --git a/arch/ia64/include/asm/machvec.h b/arch/ia64/include/asm/machvec.h
index 2d1ad4b1..989e77f 100644
--- a/arch/ia64/include/asm/machvec.h
+++ b/arch/ia64/include/asm/machvec.h
@@ -289,7 +289,7 @@ extern struct dma_map_ops *dma_get_ops(struct device *);
# define platform_dma_get_ops dma_get_ops
#endif
#ifndef platform_dma_get_required_mask
-# define platform_dma_get_required_mask ia64_dma_get_required_mask
+# define platform_dma_get_required_mask dma_get_required_mask_from_max_pfn
#endif
#ifndef platform_irq_to_vector
# define platform_irq_to_vector __ia64_irq_to_vector
diff --git a/arch/ia64/include/asm/machvec_init.h b/arch/ia64/include/asm/machvec_init.h
index 37a4698..ef964b2 100644
--- a/arch/ia64/include/asm/machvec_init.h
+++ b/arch/ia64/include/asm/machvec_init.h
@@ -3,7 +3,6 @@
extern ia64_mv_send_ipi_t ia64_send_ipi;
extern ia64_mv_global_tlb_purge_t ia64_global_tlb_purge;
-extern ia64_mv_dma_get_required_mask ia64_dma_get_required_mask;
extern ia64_mv_irq_to_vector __ia64_irq_to_vector;
extern ia64_mv_local_vector_to_irq __ia64_local_vector_to_irq;
extern ia64_mv_pci_get_legacy_mem_t ia64_pci_get_legacy_mem;
diff --git a/arch/ia64/pci/pci.c b/arch/ia64/pci/pci.c
index de1474f..e01f2c4 100644
--- a/arch/ia64/pci/pci.c
+++ b/arch/ia64/pci/pci.c
@@ -706,26 +706,6 @@ static void __init set_pci_dfl_cacheline_size(void)
pci_dfl_cache_line_size = (1 << cci.pcci_line_size) / 4;
}
-u64 ia64_dma_get_required_mask(struct device *dev)
-{
- u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
- u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
- u64 mask;
-
- if (!high_totalram) {
- /* convert to mask just covering totalram */
- low_totalram = (1 << (fls(low_totalram) - 1));
- low_totalram += low_totalram - 1;
- mask = low_totalram;
- } else {
- high_totalram = (1 << (fls(high_totalram) - 1));
- high_totalram += high_totalram - 1;
- mask = (((u64)high_totalram) << 32) + 0xffffffff;
- }
- return mask;
-}
-EXPORT_SYMBOL_GPL(ia64_dma_get_required_mask);
-
u64 dma_get_required_mask(struct device *dev)
{
return platform_dma_get_required_mask(dev);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 9eda842..c978ee1 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -916,8 +916,7 @@ int __init platform_bus_init(void)
return error;
}
-#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
-u64 dma_get_required_mask(struct device *dev)
+u64 dma_get_required_mask_from_max_pfn(struct device *dev)
{
u32 low_totalram = ((max_pfn - 1) << PAGE_SHIFT);
u32 high_totalram = ((max_pfn - 1) >> (32 - PAGE_SHIFT));
@@ -935,6 +934,13 @@ u64 dma_get_required_mask(struct device *dev)
}
return mask;
}
+EXPORT_SYMBOL_GPL(dma_get_required_mask_from_max_pfn);
+
+#ifndef ARCH_HAS_DMA_GET_REQUIRED_MASK
+u64 dma_get_required_mask(struct device *dev)
+{
+ return dma_get_required_mask_from_max_pfn(dev);
+}
EXPORT_SYMBOL_GPL(dma_get_required_mask);
#endif
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 94af418..b0bf514 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -97,6 +97,7 @@ static inline int dma_set_coherent_mask(struct device *dev, u64 mask)
}
#endif
+extern u64 dma_get_required_mask_from_max_pfn(struct device *dev);
extern u64 dma_get_required_mask(struct device *dev);
static inline unsigned int dma_get_max_seg_size(struct device *dev)
From be2602ba7152b3e2557d192c2f2a5a91d4d29e3d Mon Sep 17 00:00:00 2001
From: David Vrabel <david.vrabel@citrix.com>
Date: Fri, 9 May 2014 11:40:46 +0100
Subject: [PATCH 2/2] x86,xen: correct dma_get_required_mask() for Xen PV guests
On systems where DMA addresses and physical addresses are not 1:1
(such as Xen PV guests), the generic dma_get_required_mask() will not
return the correct mask (since it uses max_pfn).
Some device drivers (such as mptsas, mpt2sas) use
dma_get_required_mask() to set device DMA masks to allow them to use
only 32-bit DMA addresses in hardware structures. This results in
unnecessary use of the SWIOTLB if DMA addresses are more than 32-bits,
impacting performance significantly.
Provide an arch-specific dma_get_required_mask() that defaults to the
generic dma_get_required_mask_from_pfn().
Under Xen, the required DMA mask can then be set to always 64-bits.
Signed-off-by: David Vrabel <david.vrabel@citrix.com>
diff --git a/arch/x86/include/asm/device.h b/arch/x86/include/asm/device.h
index 03dd729..10bc628 100644
--- a/arch/x86/include/asm/device.h
+++ b/arch/x86/include/asm/device.h
@@ -13,4 +13,6 @@ struct dev_archdata {
struct pdev_archdata {
};
+#define ARCH_HAS_DMA_GET_REQUIRED_MASK
+
#endif /* _ASM_X86_DEVICE_H */
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index f7d0672..3423da9 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -135,6 +135,14 @@ void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
free_pages((unsigned long)vaddr, get_order(size));
}
+u64 dma_get_required_mask(struct device *dev)
+{
+ if (dma_ops->get_required_mask)
+ return dma_ops->get_required_mask(dev);
+ return dma_get_required_mask_from_max_pfn(dev);
+}
+EXPORT_SYMBOL_GPL(dma_get_required_mask);
+
/*
* See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
* parameter documentation.
diff --git a/arch/x86/xen/pci-swiotlb-xen.c b/arch/x86/xen/pci-swiotlb-xen.c
index 9695704..98eef08 100644
--- a/arch/x86/xen/pci-swiotlb-xen.c
+++ b/arch/x86/xen/pci-swiotlb-xen.c
@@ -31,6 +31,7 @@ static struct dma_map_ops xen_swiotlb_dma_ops = {
.map_page = xen_swiotlb_map_page,
.unmap_page = xen_swiotlb_unmap_page,
.dma_supported = xen_swiotlb_dma_supported,
+ .get_required_mask = xen_swiotlb_get_required_mask,
};
/*
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index 07a9b9e..92cc199 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -596,3 +596,10 @@ xen_swiotlb_dma_supported(struct device *hwdev, u64 mask)
return xen_virt_to_bus(xen_io_tlb_end - 1) <= mask;
}
EXPORT_SYMBOL_GPL(xen_swiotlb_dma_supported);
+
+u64
+xen_swiotlb_get_required_mask(struct device *dev)
+{
+ return DMA_BIT_MASK(64);
+}
+EXPORT_SYMBOL_GPL(xen_swiotlb_get_required_mask);
diff --git a/include/xen/swiotlb-xen.h b/include/xen/swiotlb-xen.h
index de8bcc6..e08d8bd 100644
--- a/include/xen/swiotlb-xen.h
+++ b/include/xen/swiotlb-xen.h
@@ -55,4 +55,7 @@ xen_swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t dma_addr);
extern int
xen_swiotlb_dma_supported(struct device *hwdev, u64 mask);
+extern u64
+xen_swiotlb_get_required_mask(struct device *dev);
+
#endif /* __LINUX_SWIOTLB_XEN_H */
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