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* [PATCH 07/22] swiotlb: add common swiotlb_map_ops
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

Currently all architectures that want to use swiotlb have to implement
their own dma_map_ops instances.  Provide a generic one based on the
x86 implementation which first calls into dma_direct to try a full blown
direct mapping implementation (including e.g. CMA) before falling back
allocating from the swiotlb buffer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/swiotlb.h |  8 ++++++++
 lib/swiotlb.c           | 43 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 606375e35d87..5b1f2a00491c 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -66,6 +66,12 @@ extern void swiotlb_tbl_sync_single(struct device *hwdev,
 				    enum dma_sync_target target);
 
 /* Accessory functions. */
+
+void *swiotlb_alloc(struct device *hwdev, size_t size, dma_addr_t *dma_handle,
+		gfp_t flags, unsigned long attrs);
+void swiotlb_free(struct device *dev, size_t size, void *vaddr,
+		dma_addr_t dma_addr, unsigned long attrs);
+
 extern void
 *swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 			dma_addr_t *dma_handle, gfp_t flags);
@@ -126,4 +132,6 @@ extern void swiotlb_print_info(void);
 extern int is_swiotlb_buffer(phys_addr_t paddr);
 extern void swiotlb_set_max_segment(unsigned int);
 
+extern const struct dma_map_ops swiotlb_dma_ops;
+
 #endif /* __LINUX_SWIOTLB_H */
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index cf5311908fa9..0fae2f45c3c0 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -1087,3 +1087,46 @@ swiotlb_dma_supported(struct device *hwdev, u64 mask)
 	return swiotlb_phys_to_dma(hwdev, io_tlb_end - 1) <= mask;
 }
 EXPORT_SYMBOL(swiotlb_dma_supported);
+
+#ifdef CONFIG_DMA_DIRECT_OPS
+void *swiotlb_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		gfp_t gfp, unsigned long attrs)
+{
+	void *vaddr;
+
+	/*
+	 * Don't print a warning when the first allocation attempt fails.
+	 * swiotlb_alloc_coherent() will print a warning when the DMA memory
+	 * allocation ultimately failed.
+	 */
+	gfp |= __GFP_NOWARN;
+
+	vaddr = dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
+	if (!vaddr)
+		vaddr = swiotlb_alloc_coherent(dev, size, dma_handle, gfp);
+	return vaddr;
+}
+
+void swiotlb_free(struct device *dev, size_t size, void *vaddr,
+		dma_addr_t dma_addr, unsigned long attrs)
+{
+	if (is_swiotlb_buffer(dma_to_phys(dev, dma_addr)))
+		swiotlb_free_coherent(dev, size, vaddr, dma_addr);
+	else
+		dma_direct_free(dev, size, vaddr, dma_addr, attrs);
+}
+
+const struct dma_map_ops swiotlb_dma_ops = {
+	.mapping_error		= swiotlb_dma_mapping_error,
+	.alloc			= swiotlb_alloc,
+	.free			= swiotlb_free,
+	.sync_single_for_cpu	= swiotlb_sync_single_for_cpu,
+	.sync_single_for_device	= swiotlb_sync_single_for_device,
+	.sync_sg_for_cpu	= swiotlb_sync_sg_for_cpu,
+	.sync_sg_for_device	= swiotlb_sync_sg_for_device,
+	.map_sg			= swiotlb_map_sg_attrs,
+	.unmap_sg		= swiotlb_unmap_sg_attrs,
+	.map_page		= swiotlb_map_page,
+	.unmap_page		= swiotlb_unmap_page,
+};
+#endif /* CONFIG_DMA_DIRECT_OPS */
-- 
2.14.2

^ permalink raw reply related

* [PATCH 06/22] swiotlb: rename swiotlb_free to swiotlb_exit
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/powerpc/kernel/dma-swiotlb.c | 2 +-
 arch/x86/kernel/pci-swiotlb.c     | 2 +-
 include/linux/swiotlb.h           | 4 ++--
 lib/swiotlb.c                     | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c
index 506ac4fafac5..88f3963ca30f 100644
--- a/arch/powerpc/kernel/dma-swiotlb.c
+++ b/arch/powerpc/kernel/dma-swiotlb.c
@@ -121,7 +121,7 @@ static int __init check_swiotlb_enabled(void)
 	if (ppc_swiotlb_enable)
 		swiotlb_print_info();
 	else
-		swiotlb_free();
+		swiotlb_exit();
 
 	return 0;
 }
diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index 0d77603c2f50..0ee0f8f34251 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -120,7 +120,7 @@ void __init pci_swiotlb_late_init(void)
 {
 	/* An IOMMU turned us off. */
 	if (!swiotlb)
-		swiotlb_free();
+		swiotlb_exit();
 	else {
 		printk(KERN_INFO "PCI-DMA: "
 		       "Using software bounce buffering for IO (SWIOTLB)\n");
diff --git a/include/linux/swiotlb.h b/include/linux/swiotlb.h
index 24ed817082ee..606375e35d87 100644
--- a/include/linux/swiotlb.h
+++ b/include/linux/swiotlb.h
@@ -115,10 +115,10 @@ extern int
 swiotlb_dma_supported(struct device *hwdev, u64 mask);
 
 #ifdef CONFIG_SWIOTLB
-extern void __init swiotlb_free(void);
+extern void __init swiotlb_exit(void);
 unsigned int swiotlb_max_segment(void);
 #else
-static inline void swiotlb_free(void) { }
+static inline void swiotlb_exit(void) { }
 static inline unsigned int swiotlb_max_segment(void) { return 0; }
 #endif
 
diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 125c1062119f..cf5311908fa9 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -417,7 +417,7 @@ swiotlb_late_init_with_tbl(char *tlb, unsigned long nslabs)
 	return -ENOMEM;
 }
 
-void __init swiotlb_free(void)
+void __init swiotlb_exit(void)
 {
 	if (!io_tlb_orig_addr)
 		return;
-- 
2.14.2

^ permalink raw reply related

* [PATCH 05/22] x86: rename swiotlb_dma_ops
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

We'll need that name for a generic implementation soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/x86/kernel/pci-swiotlb.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/pci-swiotlb.c b/arch/x86/kernel/pci-swiotlb.c
index 9d3e35c33d94..0d77603c2f50 100644
--- a/arch/x86/kernel/pci-swiotlb.c
+++ b/arch/x86/kernel/pci-swiotlb.c
@@ -48,7 +48,7 @@ void x86_swiotlb_free_coherent(struct device *dev, size_t size,
 		dma_generic_free_coherent(dev, size, vaddr, dma_addr, attrs);
 }
 
-static const struct dma_map_ops swiotlb_dma_ops = {
+static const struct dma_map_ops x86_swiotlb_dma_ops = {
 	.mapping_error = swiotlb_dma_mapping_error,
 	.alloc = x86_swiotlb_alloc_coherent,
 	.free = x86_swiotlb_free_coherent,
@@ -112,7 +112,7 @@ void __init pci_swiotlb_init(void)
 {
 	if (swiotlb) {
 		swiotlb_init(0);
-		dma_ops = &swiotlb_dma_ops;
+		dma_ops = &x86_swiotlb_dma_ops;
 	}
 }
 
-- 
2.14.2

^ permalink raw reply related

* [PATCH 04/22] powerpc: rename swiotlb_dma_ops
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

We'll need that name for a generic implementation soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/powerpc/include/asm/swiotlb.h | 2 +-
 arch/powerpc/kernel/dma-swiotlb.c  | 4 ++--
 arch/powerpc/kernel/dma.c          | 2 +-
 arch/powerpc/sysdev/fsl_pci.c      | 2 +-
 4 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/include/asm/swiotlb.h b/arch/powerpc/include/asm/swiotlb.h
index 9341ee804d19..f65ecf57b66c 100644
--- a/arch/powerpc/include/asm/swiotlb.h
+++ b/arch/powerpc/include/asm/swiotlb.h
@@ -13,7 +13,7 @@
 
 #include <linux/swiotlb.h>
 
-extern const struct dma_map_ops swiotlb_dma_ops;
+extern const struct dma_map_ops powerpc_swiotlb_dma_ops;
 
 extern unsigned int ppc_swiotlb_enable;
 int __init swiotlb_setup_bus_notifier(void);
diff --git a/arch/powerpc/kernel/dma-swiotlb.c b/arch/powerpc/kernel/dma-swiotlb.c
index f1e99b9cee97..506ac4fafac5 100644
--- a/arch/powerpc/kernel/dma-swiotlb.c
+++ b/arch/powerpc/kernel/dma-swiotlb.c
@@ -46,7 +46,7 @@ static u64 swiotlb_powerpc_get_required(struct device *dev)
  * map_page, and unmap_page on highmem, use normal dma_ops
  * for everything else.
  */
-const struct dma_map_ops swiotlb_dma_ops = {
+const struct dma_map_ops powerpc_swiotlb_dma_ops = {
 	.alloc = __dma_nommu_alloc_coherent,
 	.free = __dma_nommu_free_coherent,
 	.mmap = dma_nommu_mmap_coherent,
@@ -89,7 +89,7 @@ static int ppc_swiotlb_bus_notify(struct notifier_block *nb,
 
 	/* May need to bounce if the device can't address all of DRAM */
 	if ((dma_get_mask(dev) + 1) < memblock_end_of_DRAM())
-		set_dma_ops(dev, &swiotlb_dma_ops);
+		set_dma_ops(dev, &powerpc_swiotlb_dma_ops);
 
 	return NOTIFY_DONE;
 }
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 76079841d3d0..da20569de9d4 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -33,7 +33,7 @@ static u64 __maybe_unused get_pfn_limit(struct device *dev)
 	struct dev_archdata __maybe_unused *sd = &dev->archdata;
 
 #ifdef CONFIG_SWIOTLB
-	if (sd->max_direct_dma_addr && dev->dma_ops == &swiotlb_dma_ops)
+	if (sd->max_direct_dma_addr && dev->dma_ops == &powerpc_swiotlb_dma_ops)
 		pfn = min_t(u64, pfn, sd->max_direct_dma_addr >> PAGE_SHIFT);
 #endif
 
diff --git a/arch/powerpc/sysdev/fsl_pci.c b/arch/powerpc/sysdev/fsl_pci.c
index e4d0133bbeeb..61e07c78d64f 100644
--- a/arch/powerpc/sysdev/fsl_pci.c
+++ b/arch/powerpc/sysdev/fsl_pci.c
@@ -118,7 +118,7 @@ static void setup_swiotlb_ops(struct pci_controller *hose)
 {
 	if (ppc_swiotlb_enable) {
 		hose->controller_ops.dma_dev_setup = pci_dma_dev_setup_swiotlb;
-		set_pci_dma_ops(&swiotlb_dma_ops);
+		set_pci_dma_ops(&powerpc_swiotlb_dma_ops);
 	}
 }
 #else
-- 
2.14.2

^ permalink raw reply related

* [PATCH 03/22] ia64: rename swiotlb_dma_ops
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

We'll need that name for a generic implementation soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/ia64/hp/common/hwsw_iommu.c | 4 ++--
 arch/ia64/hp/common/sba_iommu.c  | 6 +++---
 arch/ia64/kernel/pci-swiotlb.c   | 6 +++---
 3 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/ia64/hp/common/hwsw_iommu.c b/arch/ia64/hp/common/hwsw_iommu.c
index 63d8e1d2477f..41279f0442bd 100644
--- a/arch/ia64/hp/common/hwsw_iommu.c
+++ b/arch/ia64/hp/common/hwsw_iommu.c
@@ -19,7 +19,7 @@
 #include <linux/export.h>
 #include <asm/machvec.h>
 
-extern const struct dma_map_ops sba_dma_ops, swiotlb_dma_ops;
+extern const struct dma_map_ops sba_dma_ops, ia64_swiotlb_dma_ops;
 
 /* swiotlb declarations & definitions: */
 extern int swiotlb_late_init_with_default_size (size_t size);
@@ -38,7 +38,7 @@ static inline int use_swiotlb(struct device *dev)
 const struct dma_map_ops *hwsw_dma_get_ops(struct device *dev)
 {
 	if (use_swiotlb(dev))
-		return &swiotlb_dma_ops;
+		return &ia64_swiotlb_dma_ops;
 	return &sba_dma_ops;
 }
 EXPORT_SYMBOL(hwsw_dma_get_ops);
diff --git a/arch/ia64/hp/common/sba_iommu.c b/arch/ia64/hp/common/sba_iommu.c
index aec4a3354abe..8c0a9ae6afec 100644
--- a/arch/ia64/hp/common/sba_iommu.c
+++ b/arch/ia64/hp/common/sba_iommu.c
@@ -2096,7 +2096,7 @@ static int __init acpi_sba_ioc_init_acpi(void)
 /* This has to run before acpi_scan_init(). */
 arch_initcall(acpi_sba_ioc_init_acpi);
 
-extern const struct dma_map_ops swiotlb_dma_ops;
+extern const struct dma_map_ops ia64_swiotlb_dma_ops;
 
 static int __init
 sba_init(void)
@@ -2111,7 +2111,7 @@ sba_init(void)
 	 * a successful kdump kernel boot is to use the swiotlb.
 	 */
 	if (is_kdump_kernel()) {
-		dma_ops = &swiotlb_dma_ops;
+		dma_ops = &ia64_swiotlb_dma_ops;
 		if (swiotlb_late_init_with_default_size(64 * (1<<20)) != 0)
 			panic("Unable to initialize software I/O TLB:"
 				  " Try machvec=dig boot option");
@@ -2133,7 +2133,7 @@ sba_init(void)
 		 * If we didn't find something sba_iommu can claim, we
 		 * need to setup the swiotlb and switch to the dig machvec.
 		 */
-		dma_ops = &swiotlb_dma_ops;
+		dma_ops = &ia64_swiotlb_dma_ops;
 		if (swiotlb_late_init_with_default_size(64 * (1<<20)) != 0)
 			panic("Unable to find SBA IOMMU or initialize "
 			      "software I/O TLB: Try machvec=dig boot option");
diff --git a/arch/ia64/kernel/pci-swiotlb.c b/arch/ia64/kernel/pci-swiotlb.c
index 5e50939aa03e..f1ae873a8c35 100644
--- a/arch/ia64/kernel/pci-swiotlb.c
+++ b/arch/ia64/kernel/pci-swiotlb.c
@@ -31,7 +31,7 @@ static void ia64_swiotlb_free_coherent(struct device *dev, size_t size,
 	swiotlb_free_coherent(dev, size, vaddr, dma_addr);
 }
 
-const struct dma_map_ops swiotlb_dma_ops = {
+const struct dma_map_ops ia64_swiotlb_dma_ops = {
 	.alloc = ia64_swiotlb_alloc_coherent,
 	.free = ia64_swiotlb_free_coherent,
 	.map_page = swiotlb_map_page,
@@ -48,7 +48,7 @@ const struct dma_map_ops swiotlb_dma_ops = {
 
 void __init swiotlb_dma_init(void)
 {
-	dma_ops = &swiotlb_dma_ops;
+	dma_ops = &ia64_swiotlb_dma_ops;
 	swiotlb_init(1);
 }
 
@@ -60,7 +60,7 @@ void __init pci_swiotlb_init(void)
 		printk(KERN_INFO "PCI-DMA: Re-initialize machine vector.\n");
 		machvec_init("dig");
 		swiotlb_init(1);
-		dma_ops = &swiotlb_dma_ops;
+		dma_ops = &ia64_swiotlb_dma_ops;
 #else
 		panic("Unable to find Intel IOMMU");
 #endif
-- 
2.14.2

^ permalink raw reply related

* [PATCH 02/22] arm64: rename swiotlb_dma_ops
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

We'll need that name for a generic implementation soon.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/arm64/mm/dma-mapping.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/mm/dma-mapping.c b/arch/arm64/mm/dma-mapping.c
index f3a637b98487..6840426bbe77 100644
--- a/arch/arm64/mm/dma-mapping.c
+++ b/arch/arm64/mm/dma-mapping.c
@@ -368,7 +368,7 @@ static int __swiotlb_dma_mapping_error(struct device *hwdev, dma_addr_t addr)
 	return 0;
 }
 
-static const struct dma_map_ops swiotlb_dma_ops = {
+static const struct dma_map_ops arm64_swiotlb_dma_ops = {
 	.alloc = __dma_alloc,
 	.free = __dma_free,
 	.mmap = __swiotlb_mmap,
@@ -923,7 +923,7 @@ void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
 			const struct iommu_ops *iommu, bool coherent)
 {
 	if (!dev->dma_ops)
-		dev->dma_ops = &swiotlb_dma_ops;
+		dev->dma_ops = &arm64_swiotlb_dma_ops;
 
 	dev->archdata.dma_coherent = coherent;
 	__iommu_setup_dma_ops(dev, dma_base, size, iommu);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 01/22] swiotlb: suppress warning when __GFP_NOWARN is set
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel, Christian König,
	stable
In-Reply-To: <20180110080932.14157-1-hch@lst.de>

From: Christian König <ckoenig.leichtzumerken@gmail.com>

TTM tries to allocate coherent memory in chunks of 2MB first to improve
TLB efficiency and falls back to allocating 4K pages if that fails.

Suppress the warning when the 2MB allocations fails since there is a
valid fall back path.

Signed-off-by: Christian König <christian.koenig@amd.com>
Reported-by: Mike Galbraith <efault@gmx.de>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=104082
CC: stable@vger.kernel.org
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/swiotlb.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/lib/swiotlb.c b/lib/swiotlb.c
index 6583f3512386..125c1062119f 100644
--- a/lib/swiotlb.c
+++ b/lib/swiotlb.c
@@ -586,7 +586,7 @@ phys_addr_t swiotlb_tbl_map_single(struct device *hwdev,
 
 not_found:
 	spin_unlock_irqrestore(&io_tlb_lock, flags);
-	if (printk_ratelimit())
+	if (!(attrs & DMA_ATTR_NO_WARN) && printk_ratelimit())
 		dev_warn(hwdev, "swiotlb buffer is full (sz: %zd bytes)\n", size);
 	return SWIOTLB_MAP_ERROR;
 found:
@@ -713,6 +713,7 @@ void *
 swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 		       dma_addr_t *dma_handle, gfp_t flags)
 {
+	bool warn = !(flags & __GFP_NOWARN);
 	dma_addr_t dev_addr;
 	void *ret;
 	int order = get_order(size);
@@ -738,8 +739,8 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 		 * GFP_DMA memory; fall back on map_single(), which
 		 * will grab memory from the lowest available address range.
 		 */
-		phys_addr_t paddr = map_single(hwdev, 0, size,
-					       DMA_FROM_DEVICE, 0);
+		phys_addr_t paddr = map_single(hwdev, 0, size, DMA_FROM_DEVICE,
+					       warn ? 0 : DMA_ATTR_NO_WARN);
 		if (paddr == SWIOTLB_MAP_ERROR)
 			goto err_warn;
 
@@ -769,9 +770,11 @@ swiotlb_alloc_coherent(struct device *hwdev, size_t size,
 	return ret;
 
 err_warn:
-	pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n",
-		dev_name(hwdev), size);
-	dump_stack();
+	if (warn && printk_ratelimit()) {
+		pr_warn("swiotlb: coherent allocation failed for device %s size=%zu\n",
+			dev_name(hwdev), size);
+		dump_stack();
+	}
 
 	return NULL;
 }
-- 
2.14.2

^ permalink raw reply related

* consolidate swiotlb dma_map implementations
From: Christoph Hellwig @ 2018-01-10  8:09 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, Michal Simek, Guan Xuetao,
	Christian König, linux-arm-kernel, linux-ia64, linux-mips,
	linuxppc-dev, x86, linux-arch, linux-kernel

A lot of architectures have essentially identical dma_map_ops
implementations to use swiotlb.  This series adds new generic
swiotlb_alloc/free helpers that take the attrs argument exposed
in dma_map_ops, and which do an enhanced direct allocation
modelled after x86 and reused from the dma-direct code, and
then switches most architectures over to it.  The only exceptions
are mips, which requires additional cache flushing which will
need a new abstraction, and x86 itself which will be handled in
a later series with other x86 dma mapping changes.

To support the generic code a few architectures that currently
use ZONE_DMA/GFP_DMA for <= 32-bit allocations are switched to
implement ZONE_DMA32 instead.

This series is based on the previously sent series to consolidate
the direct dma mapping implementation.  A git tree with this
series as well as the prerequisites is available here:

   git://git.infradead.org/users/hch/misc.git swiotlb

Gitweb:

   http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/swiotlb

^ permalink raw reply

* [PATCH 33/33] h8300: use dma-direct
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Replace the bare-bones h8300 direct dma mapping implementation with
the fully featured generic dma-direct one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/h8300/Kconfig                   |  1 +
 arch/h8300/include/asm/Kbuild        |  1 +
 arch/h8300/include/asm/dma-mapping.h | 12 -------
 arch/h8300/kernel/Makefile           |  2 +-
 arch/h8300/kernel/dma.c              | 66 ------------------------------------
 5 files changed, 3 insertions(+), 79 deletions(-)
 delete mode 100644 arch/h8300/include/asm/dma-mapping.h
 delete mode 100644 arch/h8300/kernel/dma.c

diff --git a/arch/h8300/Kconfig b/arch/h8300/Kconfig
index f8d3fde08190..091d6d04b5e5 100644
--- a/arch/h8300/Kconfig
+++ b/arch/h8300/Kconfig
@@ -23,6 +23,7 @@ config H8300
 	select HAVE_ARCH_KGDB
 	select HAVE_ARCH_HASH
 	select CPU_NO_EFFICIENT_FFS
+	select DMA_DIRECT_OPS
 
 config CPU_BIG_ENDIAN
 	def_bool y
diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild
index bc077491d299..642752c94306 100644
--- a/arch/h8300/include/asm/Kbuild
+++ b/arch/h8300/include/asm/Kbuild
@@ -9,6 +9,7 @@ generic-y += delay.h
 generic-y += device.h
 generic-y += div64.h
 generic-y += dma.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += exec.h
 generic-y += extable.h
diff --git a/arch/h8300/include/asm/dma-mapping.h b/arch/h8300/include/asm/dma-mapping.h
deleted file mode 100644
index 21bb1fc3a6f1..000000000000
--- a/arch/h8300/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,12 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _H8300_DMA_MAPPING_H
-#define _H8300_DMA_MAPPING_H
-
-extern const struct dma_map_ops h8300_dma_map_ops;
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &h8300_dma_map_ops;
-}
-
-#endif
diff --git a/arch/h8300/kernel/Makefile b/arch/h8300/kernel/Makefile
index b62e830525c6..307aa51576dd 100644
--- a/arch/h8300/kernel/Makefile
+++ b/arch/h8300/kernel/Makefile
@@ -7,7 +7,7 @@ extra-y := vmlinux.lds
 
 obj-y := process.o traps.o ptrace.o \
 	 signal.o setup.o syscalls.o \
-	 irq.o entry.o dma.o
+	 irq.o entry.o
 
 obj-$(CONFIG_ROMKERNEL) += head_rom.o
 obj-$(CONFIG_RAMKERNEL) += head_ram.o
diff --git a/arch/h8300/kernel/dma.c b/arch/h8300/kernel/dma.c
deleted file mode 100644
index d44ba5db4ac3..000000000000
--- a/arch/h8300/kernel/dma.c
+++ /dev/null
@@ -1,66 +0,0 @@
-/*
- * This file is subject to the terms and conditions of the GNU General Public
- * License.  See the file COPYING in the main directory of this archive
- * for more details.
- */
-
-#include <linux/dma-mapping.h>
-#include <linux/kernel.h>
-#include <linux/scatterlist.h>
-#include <linux/module.h>
-#include <asm/pgalloc.h>
-
-static void *dma_alloc(struct device *dev, size_t size,
-		       dma_addr_t *dma_handle, gfp_t gfp,
-		       unsigned long attrs)
-{
-	void *ret;
-
-	if (dev == NULL || (*dev->dma_mask < 0xffffffff))
-		gfp |= GFP_DMA;
-	ret = (void *)__get_free_pages(gfp, get_order(size));
-
-	if (ret != NULL) {
-		memset(ret, 0, size);
-		*dma_handle = virt_to_phys(ret);
-	}
-	return ret;
-}
-
-static void dma_free(struct device *dev, size_t size,
-		     void *vaddr, dma_addr_t dma_handle,
-		     unsigned long attrs)
-
-{
-	free_pages((unsigned long)vaddr, get_order(size));
-}
-
-static dma_addr_t map_page(struct device *dev, struct page *page,
-				  unsigned long offset, size_t size,
-				  enum dma_data_direction direction,
-				  unsigned long attrs)
-{
-	return page_to_phys(page) + offset;
-}
-
-static int map_sg(struct device *dev, struct scatterlist *sgl,
-		  int nents, enum dma_data_direction direction,
-		  unsigned long attrs)
-{
-	struct scatterlist *sg;
-	int i;
-
-	for_each_sg(sgl, sg, nents, i) {
-		sg->dma_address = sg_phys(sg);
-	}
-
-	return nents;
-}
-
-const struct dma_map_ops h8300_dma_map_ops = {
-	.alloc = dma_alloc,
-	.free = dma_free,
-	.map_page = map_page,
-	.map_sg = map_sg,
-};
-EXPORT_SYMBOL(h8300_dma_map_ops);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 32/33] cris: use dma-direct
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

cris currently has an incomplete direct mapping dma_map_ops implementation
is PCI support is enabled.  Replace it with the fully feature generic
dma-direct implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
---
 arch/cris/Kconfig                       |  4 ++
 arch/cris/arch-v32/drivers/pci/Makefile |  2 +-
 arch/cris/arch-v32/drivers/pci/dma.c    | 77 ---------------------------------
 arch/cris/include/asm/Kbuild            |  1 +
 arch/cris/include/asm/dma-mapping.h     | 20 ---------
 5 files changed, 6 insertions(+), 98 deletions(-)
 delete mode 100644 arch/cris/arch-v32/drivers/pci/dma.c
 delete mode 100644 arch/cris/include/asm/dma-mapping.h

diff --git a/arch/cris/Kconfig b/arch/cris/Kconfig
index 54d3f426763b..cd5a0865c97f 100644
--- a/arch/cris/Kconfig
+++ b/arch/cris/Kconfig
@@ -33,6 +33,9 @@ config GENERIC_CALIBRATE_DELAY
 config NO_IOPORT_MAP
 	def_bool y if !PCI
 
+config NO_DMA
+	def_bool y if !PCI
+
 config FORCE_MAX_ZONEORDER
 	int
 	default 6
@@ -72,6 +75,7 @@ config CRIS
 	select GENERIC_SCHED_CLOCK if ETRAX_ARCH_V32
 	select HAVE_DEBUG_BUGVERBOSE if ETRAX_ARCH_V32
 	select HAVE_NMI
+	select DMA_DIRECT_OPS if PCI
 
 config HZ
 	int
diff --git a/arch/cris/arch-v32/drivers/pci/Makefile b/arch/cris/arch-v32/drivers/pci/Makefile
index bff7482f2444..93c8be6170b1 100644
--- a/arch/cris/arch-v32/drivers/pci/Makefile
+++ b/arch/cris/arch-v32/drivers/pci/Makefile
@@ -2,4 +2,4 @@
 # Makefile for Etrax cardbus driver
 #
 
-obj-$(CONFIG_ETRAX_CARDBUS)        += bios.o dma.o
+obj-$(CONFIG_ETRAX_CARDBUS)        += bios.o
diff --git a/arch/cris/arch-v32/drivers/pci/dma.c b/arch/cris/arch-v32/drivers/pci/dma.c
deleted file mode 100644
index 8c3802244ef3..000000000000
--- a/arch/cris/arch-v32/drivers/pci/dma.c
+++ /dev/null
@@ -1,77 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Dynamic DMA mapping support.
- *
- * On cris there is no hardware dynamic DMA address translation,
- * so consistent alloc/free are merely page allocation/freeing.
- * The rest of the dynamic DMA mapping interface is implemented
- * in asm/pci.h.
- *
- * Borrowed from i386.
- */
-
-#include <linux/types.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/pci.h>
-#include <linux/gfp.h>
-#include <asm/io.h>
-
-static void *v32_dma_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
-{
-	void *ret;
-
-	if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
-		gfp |= GFP_DMA;
-
-	ret = (void *)__get_free_pages(gfp,  get_order(size));
-
-	if (ret != NULL) {
-		memset(ret, 0, size);
-		*dma_handle = virt_to_phys(ret);
-	}
-	return ret;
-}
-
-static void v32_dma_free(struct device *dev, size_t size, void *vaddr,
-		dma_addr_t dma_handle, unsigned long attrs)
-{
-	free_pages((unsigned long)vaddr, get_order(size));
-}
-
-static inline dma_addr_t v32_dma_map_page(struct device *dev,
-		struct page *page, unsigned long offset, size_t size,
-		enum dma_data_direction direction, unsigned long attrs)
-{
-	return page_to_phys(page) + offset;
-}
-
-static inline int v32_dma_map_sg(struct device *dev, struct scatterlist *sg,
-		int nents, enum dma_data_direction direction,
-		unsigned long attrs)
-{
-	printk("Map sg\n");
-	return nents;
-}
-
-static inline int v32_dma_supported(struct device *dev, u64 mask)
-{
-        /*
-         * we fall back to GFP_DMA when the mask isn't all 1s,
-         * so we can't guarantee allocations that must be
-         * within a tighter range than GFP_DMA..
-         */
-        if (mask < 0x00ffffff)
-                return 0;
-	return 1;
-}
-
-const struct dma_map_ops v32_dma_ops = {
-	.alloc			= v32_dma_alloc,
-	.free			= v32_dma_free,
-	.map_page		= v32_dma_map_page,
-	.map_sg                 = v32_dma_map_sg,
-	.dma_supported		= v32_dma_supported,
-};
-EXPORT_SYMBOL(v32_dma_ops);
diff --git a/arch/cris/include/asm/Kbuild b/arch/cris/include/asm/Kbuild
index 460349cb147f..8cf45ac30c1b 100644
--- a/arch/cris/include/asm/Kbuild
+++ b/arch/cris/include/asm/Kbuild
@@ -5,6 +5,7 @@ generic-y += cmpxchg.h
 generic-y += current.h
 generic-y += device.h
 generic-y += div64.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += exec.h
 generic-y += extable.h
diff --git a/arch/cris/include/asm/dma-mapping.h b/arch/cris/include/asm/dma-mapping.h
deleted file mode 100644
index 1553bdb30a0c..000000000000
--- a/arch/cris/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,20 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_CRIS_DMA_MAPPING_H
-#define _ASM_CRIS_DMA_MAPPING_H
-
-#ifdef CONFIG_PCI
-extern const struct dma_map_ops v32_dma_ops;
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &v32_dma_ops;
-}
-#else
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	BUG();
-	return NULL;
-}
-#endif
-
-#endif
-- 
2.14.2

^ permalink raw reply related

* [PATCH 31/33] dma-direct: reject too small dma masks
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/dma-direct.h |  1 +
 lib/dma-direct.c           | 19 +++++++++++++++++++
 2 files changed, 20 insertions(+)

diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index 4788bf0bf683..bcdb1a3e4b1f 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -42,5 +42,6 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
 		gfp_t gfp, unsigned long attrs);
 void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
 		dma_addr_t dma_addr, unsigned long attrs);
+int dma_direct_supported(struct device *dev, u64 mask);
 
 #endif /* _LINUX_DMA_DIRECT_H */
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 784a68dfdbe3..40b1f92f2214 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -122,6 +122,24 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
 	return nents;
 }
 
+int dma_direct_supported(struct device *dev, u64 mask)
+{
+#ifdef CONFIG_ZONE_DMA
+	if (mask < DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
+		return 0;
+#else
+	/*
+	 * Because 32-bit DMA masks are so common we expect every architecture
+	 * to be able to satisfy them - either by not supporting more physical
+	 * memory, or by providing a ZONE_DMA32.  If neither is the case, the
+	 * architecture needs to use an IOMMU instead of the direct mapping.
+	 */
+	if (mask < DMA_BIT_MASK(32))
+		return 0;
+#endif
+	return 1;
+}
+
 static int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
 {
 	return dma_addr == DIRECT_MAPPING_ERROR;
@@ -132,6 +150,7 @@ const struct dma_map_ops dma_direct_ops = {
 	.free			= dma_direct_free,
 	.map_page		= dma_direct_map_page,
 	.map_sg			= dma_direct_map_sg,
+	.dma_supported		= dma_direct_supported,
 	.mapping_error		= dma_direct_mapping_error,
 };
 EXPORT_SYMBOL(dma_direct_ops);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 30/33] dma-direct: make dma_direct_{alloc, free} available to other implementations
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

So that they don't need to indirect through the operation vector.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 arch/arm/mm/dma-mapping-nommu.c | 9 +++------
 include/linux/dma-direct.h      | 5 +++++
 lib/dma-direct.c                | 6 +++---
 3 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
index 4d8042521e89..619f24a42d09 100644
--- a/arch/arm/mm/dma-mapping-nommu.c
+++ b/arch/arm/mm/dma-mapping-nommu.c
@@ -11,7 +11,7 @@
 
 #include <linux/export.h>
 #include <linux/mm.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/scatterlist.h>
 
 #include <asm/cachetype.h>
@@ -39,7 +39,6 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
 				 unsigned long attrs)
 
 {
-	const struct dma_map_ops *ops = &dma_direct_ops;
 	void *ret;
 
 	/*
@@ -48,7 +47,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
 	 */
 
 	if (attrs & DMA_ATTR_NON_CONSISTENT)
-		return ops->alloc(dev, size, dma_handle, gfp, attrs);
+		return dma_direct_alloc(dev, size, dma_handle, gfp, attrs);
 
 	ret = dma_alloc_from_global_coherent(size, dma_handle);
 
@@ -70,10 +69,8 @@ static void arm_nommu_dma_free(struct device *dev, size_t size,
 			       void *cpu_addr, dma_addr_t dma_addr,
 			       unsigned long attrs)
 {
-	const struct dma_map_ops *ops = &dma_direct_ops;
-
 	if (attrs & DMA_ATTR_NON_CONSISTENT) {
-		ops->free(dev, size, cpu_addr, dma_addr, attrs);
+		dma_direct_free(dev, size, cpu_addr, dma_addr, attrs);
 	} else {
 		int ret = dma_release_from_global_coherent(get_order(size),
 							   cpu_addr);
diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index 10e924b7cba7..4788bf0bf683 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -38,4 +38,9 @@ static inline void dma_mark_clean(void *addr, size_t size)
 }
 #endif /* CONFIG_ARCH_HAS_DMA_MARK_CLEAN */
 
+void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		gfp_t gfp, unsigned long attrs);
+void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+		dma_addr_t dma_addr, unsigned long attrs);
+
 #endif /* _LINUX_DMA_DIRECT_H */
diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 4e43c2bb7f5f..784a68dfdbe3 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -40,8 +40,8 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
 	return phys_to_dma(dev, phys) + size - 1 <= dev->coherent_dma_mask;
 }
 
-static void *dma_direct_alloc(struct device *dev, size_t size,
-		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
+void *dma_direct_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		gfp_t gfp, unsigned long attrs)
 {
 	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
 	int page_order = get_order(size);
@@ -84,7 +84,7 @@ static void *dma_direct_alloc(struct device *dev, size_t size,
 	return page_address(page);
 }
 
-static void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
 		dma_addr_t dma_addr, unsigned long attrs)
 {
 	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-- 
2.14.2

^ permalink raw reply related

* [PATCH 29/33] dma-direct: retry allocations using GFP_DMA for small masks
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

If an attempt to allocate memory succeeded, but isn't inside the
supported DMA mask, retry the allocation with GFP_DMA set as a
last resort.

Based on the x86 code, but an off by one error in what is now
dma_coherent_ok has been fixed vs the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/dma-direct.c | 25 ++++++++++++++++++++++++-
 1 file changed, 24 insertions(+), 1 deletion(-)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 8f76032ebc3c..4e43c2bb7f5f 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -35,6 +35,11 @@ check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
 	return true;
 }
 
+static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
+{
+	return phys_to_dma(dev, phys) + size - 1 <= dev->coherent_dma_mask;
+}
+
 static void *dma_direct_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
@@ -48,11 +53,29 @@ static void *dma_direct_alloc(struct device *dev, size_t size,
 	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
 		gfp |= GFP_DMA32;
 
+again:
 	/* CMA can be used only in the context which permits sleeping */
-	if (gfpflags_allow_blocking(gfp))
+	if (gfpflags_allow_blocking(gfp)) {
 		page = dma_alloc_from_contiguous(dev, count, page_order, gfp);
+		if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+			dma_release_from_contiguous(dev, page, count);
+			page = NULL;
+		}
+	}
 	if (!page)
 		page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
+
+	if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
+		__free_pages(page, page_order);
+		page = NULL;
+
+		if (dev->coherent_dma_mask < DMA_BIT_MASK(32) &&
+		    !(gfp & GFP_DMA)) {
+			gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
+			goto again;
+		}
+	}
+
 	if (!page)
 		return NULL;
 
-- 
2.14.2

^ permalink raw reply related

* [PATCH 28/33] dma-direct: add support for allocation from ZONE_DMA and ZONE_DMA32
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

This allows to dip into zones for lower memory if they are available.
If one of the zones is not available the corresponding GFP_* flag
will evaluate to 0 so they won't change anything.  We provide an
arch tunable for those architectures that do not use GFP_DMA for
the lowest 24-bits, given that there are a few.

Roughly based on the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/dma-direct.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index f04a424f91fa..8f76032ebc3c 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -12,6 +12,14 @@
 
 #define DIRECT_MAPPING_ERROR		0
 
+/*
+ * Most architectures use ZONE_DMA for the first 16 Megabytes, but
+ * some use it for entirely different regions:
+ */
+#ifndef ARCH_ZONE_DMA_BITS
+#define ARCH_ZONE_DMA_BITS 24
+#endif
+
 static bool
 check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
 		const char *caller)
@@ -34,6 +42,12 @@ static void *dma_direct_alloc(struct device *dev, size_t size,
 	int page_order = get_order(size);
 	struct page *page = NULL;
 
+	/* GFP_DMA32 and GFP_DMA are no ops without the corresponding zones: */
+	if (dev->coherent_dma_mask <= DMA_BIT_MASK(ARCH_ZONE_DMA_BITS))
+		gfp |= GFP_DMA;
+	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32) && !(gfp & GFP_DMA))
+		gfp |= GFP_DMA32;
+
 	/* CMA can be used only in the context which permits sleeping */
 	if (gfpflags_allow_blocking(gfp))
 		page = dma_alloc_from_contiguous(dev, count, page_order, gfp);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 27/33] dma-direct: use node local allocations for coherent memory
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

To preserve the x86 behavior.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/dma-direct.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index a9ae98be7af3..f04a424f91fa 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -38,7 +38,7 @@ static void *dma_direct_alloc(struct device *dev, size_t size,
 	if (gfpflags_allow_blocking(gfp))
 		page = dma_alloc_from_contiguous(dev, count, page_order, gfp);
 	if (!page)
-		page = alloc_pages(gfp, page_order);
+		page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
 	if (!page)
 		return NULL;
 
-- 
2.14.2

^ permalink raw reply related

* [PATCH 25/33] dma-direct: add dma address sanity checks
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Roughly based on the x86 pci-nommu implementation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/dma-direct.c | 31 ++++++++++++++++++++++++++++++-
 1 file changed, 30 insertions(+), 1 deletion(-)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 12ea9653781b..32fd4d9e4c47 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -9,6 +9,23 @@
 #include <linux/scatterlist.h>
 #include <linux/pfn.h>
 
+#define DIRECT_MAPPING_ERROR		0
+
+static bool
+check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
+		const char *caller)
+{
+	if (unlikely(dev && !dma_capable(dev, dma_addr, size))) {
+		if (*dev->dma_mask >= DMA_BIT_MASK(32)) {
+			dev_err(dev,
+				"%s: overflow %pad+%zu of device mask %llx\n",
+				caller, &dma_addr, size, *dev->dma_mask);
+		}
+		return false;
+	}
+	return true;
+}
+
 static void *dma_direct_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
@@ -31,7 +48,11 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
 		unsigned long offset, size_t size, enum dma_data_direction dir,
 		unsigned long attrs)
 {
-	return phys_to_dma(dev, page_to_phys(page)) + offset;
+	dma_addr_t dma_addr = phys_to_dma(dev, page_to_phys(page)) + offset;
+
+	if (!check_addr(dev, dma_addr, size, __func__))
+		return DIRECT_MAPPING_ERROR;
+	return dma_addr;
 }
 
 static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
@@ -44,16 +65,24 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
 		BUG_ON(!sg_page(sg));
 
 		sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg));
+		if (!check_addr(dev, sg_dma_address(sg), sg->length, __func__))
+			return 0;
 		sg_dma_len(sg) = sg->length;
 	}
 
 	return nents;
 }
 
+static int dma_direct_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+	return dma_addr == DIRECT_MAPPING_ERROR;
+}
+
 const struct dma_map_ops dma_direct_ops = {
 	.alloc			= dma_direct_alloc,
 	.free			= dma_direct_free,
 	.map_page		= dma_direct_map_page,
 	.map_sg			= dma_direct_map_sg,
+	.mapping_error		= dma_direct_mapping_error,
 };
 EXPORT_SYMBOL(dma_direct_ops);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 26/33] dma-direct: add support for CMA allocation
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Try the CMA allocator for coherent allocations if supported.

Roughly modelled after the x86 code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 lib/dma-direct.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 32fd4d9e4c47..a9ae98be7af3 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -7,6 +7,7 @@
 #include <linux/mm.h>
 #include <linux/dma-direct.h>
 #include <linux/scatterlist.h>
+#include <linux/dma-contiguous.h>
 #include <linux/pfn.h>
 
 #define DIRECT_MAPPING_ERROR		0
@@ -29,19 +30,30 @@ check_addr(struct device *dev, dma_addr_t dma_addr, size_t size,
 static void *dma_direct_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
-	void *ret;
+	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+	int page_order = get_order(size);
+	struct page *page = NULL;
 
-	ret = (void *)__get_free_pages(gfp, get_order(size));
-	if (ret)
-		*dma_handle = phys_to_dma(dev, virt_to_phys(ret));
+	/* CMA can be used only in the context which permits sleeping */
+	if (gfpflags_allow_blocking(gfp))
+		page = dma_alloc_from_contiguous(dev, count, page_order, gfp);
+	if (!page)
+		page = alloc_pages(gfp, page_order);
+	if (!page)
+		return NULL;
 
-	return ret;
+	*dma_handle = phys_to_dma(dev, page_to_phys(page));
+	memset(page_address(page), 0, size);
+	return page_address(page);
 }
 
 static void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
 		dma_addr_t dma_addr, unsigned long attrs)
 {
-	free_pages((unsigned long)cpu_addr, get_order(size));
+	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+	if (!dma_release_from_contiguous(dev, virt_to_page(cpu_addr), count))
+		free_pages((unsigned long)cpu_addr, get_order(size));
 }
 
 static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
-- 
2.14.2

^ permalink raw reply related

* [PATCH 24/33] dma-direct: use phys_to_dma
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

This means it uses whatever linear remapping scheme that the architecture
provides is used in the generic dma_direct ops.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 lib/dma-direct.c | 18 +++++++-----------
 1 file changed, 7 insertions(+), 11 deletions(-)

diff --git a/lib/dma-direct.c b/lib/dma-direct.c
index 0ec3262a3148..12ea9653781b 100644
--- a/lib/dma-direct.c
+++ b/lib/dma-direct.c
@@ -1,12 +1,11 @@
 // SPDX-License-Identifier: GPL-2.0
 /*
- *	lib/dma-noop.c
- *
- * DMA operations that map to physical addresses without flushing memory.
+ * DMA operations that map physical memory directly without using an IOMMU or
+ * flushing caches.
  */
 #include <linux/export.h>
 #include <linux/mm.h>
-#include <linux/dma-mapping.h>
+#include <linux/dma-direct.h>
 #include <linux/scatterlist.h>
 #include <linux/pfn.h>
 
@@ -17,7 +16,7 @@ static void *dma_direct_alloc(struct device *dev, size_t size,
 
 	ret = (void *)__get_free_pages(gfp, get_order(size));
 	if (ret)
-		*dma_handle = virt_to_phys(ret) - PFN_PHYS(dev->dma_pfn_offset);
+		*dma_handle = phys_to_dma(dev, virt_to_phys(ret));
 
 	return ret;
 }
@@ -32,7 +31,7 @@ static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
 		unsigned long offset, size_t size, enum dma_data_direction dir,
 		unsigned long attrs)
 {
-	return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);
+	return phys_to_dma(dev, page_to_phys(page)) + offset;
 }
 
 static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
@@ -42,12 +41,9 @@ static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
 	struct scatterlist *sg;
 
 	for_each_sg(sgl, sg, nents, i) {
-		dma_addr_t offset = PFN_PHYS(dev->dma_pfn_offset);
-		void *va;
-
 		BUG_ON(!sg_page(sg));
-		va = sg_virt(sg);
-		sg_dma_address(sg) = (dma_addr_t)virt_to_phys(va) - offset;
+
+		sg_dma_address(sg) = phys_to_dma(dev, sg_phys(sg));
 		sg_dma_len(sg) = sg->length;
 	}
 
-- 
2.14.2

^ permalink raw reply related

* [PATCH 23/33] dma-direct: rename dma_noop to dma_direct
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

The trivial direct mapping implementation already does a virtual to
physical translation which isn't strictly a noop, and will soon learn
to do non-direct but linear physical to dma translations through the
device offset and a few small tricks.  Rename it to a better fitting
name.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Vladimir Murzin <vladimir.murzin@arm.com>
---
 MAINTAINERS                        |  2 +-
 arch/arm/Kconfig                   |  2 +-
 arch/arm/include/asm/dma-mapping.h |  2 +-
 arch/arm/mm/dma-mapping-nommu.c    |  8 ++++----
 arch/m32r/Kconfig                  |  2 +-
 arch/riscv/Kconfig                 |  2 +-
 arch/s390/Kconfig                  |  2 +-
 include/asm-generic/dma-mapping.h  |  2 +-
 include/linux/dma-mapping.h        |  2 +-
 lib/Kconfig                        |  2 +-
 lib/Makefile                       |  2 +-
 lib/{dma-noop.c => dma-direct.c}   | 35 +++++++++++++++--------------------
 12 files changed, 29 insertions(+), 34 deletions(-)
 rename lib/{dma-noop.c => dma-direct.c} (52%)

diff --git a/MAINTAINERS b/MAINTAINERS
index 234e642e7149..2d54e636d625 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4334,7 +4334,7 @@ T:	git git://git.infradead.org/users/hch/dma-mapping.git
 W:	http://git.infradead.org/users/hch/dma-mapping.git
 S:	Supported
 F:	lib/dma-debug.c
-F:	lib/dma-noop.c
+F:	lib/dma-direct.c
 F:	lib/dma-virt.c
 F:	drivers/base/dma-mapping.c
 F:	drivers/base/dma-coherent.c
diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 00d889a37965..430a0aa710d6 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -25,7 +25,7 @@ config ARM
 	select CLONE_BACKWARDS
 	select CPU_PM if (SUSPEND || CPU_IDLE)
 	select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
-	select DMA_NOOP_OPS if !MMU
+	select DMA_DIRECT_OPS if !MMU
 	select EDAC_SUPPORT
 	select EDAC_ATOMIC_SCRUB
 	select GENERIC_ALLOCATOR
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index e5d9020c9ee1..8436f6ade57d 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -18,7 +18,7 @@ extern const struct dma_map_ops arm_coherent_dma_ops;
 
 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 {
-	return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_noop_ops;
+	return IS_ENABLED(CONFIG_MMU) ? &arm_dma_ops : &dma_direct_ops;
 }
 
 #ifdef __arch_page_to_dma
diff --git a/arch/arm/mm/dma-mapping-nommu.c b/arch/arm/mm/dma-mapping-nommu.c
index 6db5fc26d154..4d8042521e89 100644
--- a/arch/arm/mm/dma-mapping-nommu.c
+++ b/arch/arm/mm/dma-mapping-nommu.c
@@ -22,7 +22,7 @@
 #include "dma.h"
 
 /*
- *  dma_noop_ops is used if
+ *  dma_direct_ops is used if
  *   - MMU/MPU is off
  *   - cpu is v7m w/o cache support
  *   - device is coherent
@@ -39,7 +39,7 @@ static void *arm_nommu_dma_alloc(struct device *dev, size_t size,
 				 unsigned long attrs)
 
 {
-	const struct dma_map_ops *ops = &dma_noop_ops;
+	const struct dma_map_ops *ops = &dma_direct_ops;
 	void *ret;
 
 	/*
@@ -70,7 +70,7 @@ static void arm_nommu_dma_free(struct device *dev, size_t size,
 			       void *cpu_addr, dma_addr_t dma_addr,
 			       unsigned long attrs)
 {
-	const struct dma_map_ops *ops = &dma_noop_ops;
+	const struct dma_map_ops *ops = &dma_direct_ops;
 
 	if (attrs & DMA_ATTR_NON_CONSISTENT) {
 		ops->free(dev, size, cpu_addr, dma_addr, attrs);
@@ -213,7 +213,7 @@ EXPORT_SYMBOL(arm_nommu_dma_ops);
 
 static const struct dma_map_ops *arm_nommu_get_dma_map_ops(bool coherent)
 {
-	return coherent ? &dma_noop_ops : &arm_nommu_dma_ops;
+	return coherent ? &dma_direct_ops : &arm_nommu_dma_ops;
 }
 
 void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
diff --git a/arch/m32r/Kconfig b/arch/m32r/Kconfig
index 498398d915c1..dd84ee194579 100644
--- a/arch/m32r/Kconfig
+++ b/arch/m32r/Kconfig
@@ -19,7 +19,7 @@ config M32R
 	select MODULES_USE_ELF_RELA
 	select HAVE_DEBUG_STACKOVERFLOW
 	select CPU_NO_EFFICIENT_FFS
-	select DMA_NOOP_OPS
+	select DMA_DIRECT_OPS
 	select ARCH_NO_COHERENT_DMA_MMAP if !MMU
 
 config SBUS
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 2c6adf12713a..865e14f50c14 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -83,7 +83,7 @@ config PGTABLE_LEVELS
 config HAVE_KPROBES
 	def_bool n
 
-config DMA_NOOP_OPS
+config DMA_DIRECT_OPS
 	def_bool y
 
 menu "Platform type"
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 829c67986db7..9376637229c9 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -140,7 +140,7 @@ config S390
 	select HAVE_DEBUG_KMEMLEAK
 	select HAVE_DMA_API_DEBUG
 	select HAVE_DMA_CONTIGUOUS
-	select DMA_NOOP_OPS
+	select DMA_DIRECT_OPS
 	select HAVE_DYNAMIC_FTRACE
 	select HAVE_DYNAMIC_FTRACE_WITH_REGS
 	select HAVE_EFFICIENT_UNALIGNED_ACCESS
diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h
index 164031531d85..880a292d792f 100644
--- a/include/asm-generic/dma-mapping.h
+++ b/include/asm-generic/dma-mapping.h
@@ -4,7 +4,7 @@
 
 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 {
-	return &dma_noop_ops;
+	return &dma_direct_ops;
 }
 
 #endif /* _ASM_GENERIC_DMA_MAPPING_H */
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index d67742dad904..b626028a3e47 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -136,7 +136,7 @@ struct dma_map_ops {
 	int is_phys;
 };
 
-extern const struct dma_map_ops dma_noop_ops;
+extern const struct dma_map_ops dma_direct_ops;
 extern const struct dma_map_ops dma_virt_ops;
 
 #define DMA_BIT_MASK(n)	(((n) == 64) ? ~0ULL : ((1ULL<<(n))-1))
diff --git a/lib/Kconfig b/lib/Kconfig
index c5e84fbcb30b..9d3d649c9dc9 100644
--- a/lib/Kconfig
+++ b/lib/Kconfig
@@ -409,7 +409,7 @@ config HAS_DMA
 	depends on !NO_DMA
 	default y
 
-config DMA_NOOP_OPS
+config DMA_DIRECT_OPS
 	bool
 	depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
 	default n
diff --git a/lib/Makefile b/lib/Makefile
index d11c48ec8ffd..749851abe85a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -28,7 +28,7 @@ lib-y := ctype.o string.o vsprintf.o cmdline.o \
 
 lib-$(CONFIG_MMU) += ioremap.o
 lib-$(CONFIG_SMP) += cpumask.o
-lib-$(CONFIG_DMA_NOOP_OPS) += dma-noop.o
+lib-$(CONFIG_DMA_DIRECT_OPS) += dma-direct.o
 lib-$(CONFIG_DMA_VIRT_OPS) += dma-virt.o
 
 lib-y	+= kobject.o klist.o
diff --git a/lib/dma-noop.c b/lib/dma-direct.c
similarity index 52%
rename from lib/dma-noop.c
rename to lib/dma-direct.c
index a10185b0c2d4..0ec3262a3148 100644
--- a/lib/dma-noop.c
+++ b/lib/dma-direct.c
@@ -10,9 +10,8 @@
 #include <linux/scatterlist.h>
 #include <linux/pfn.h>
 
-static void *dma_noop_alloc(struct device *dev, size_t size,
-			    dma_addr_t *dma_handle, gfp_t gfp,
-			    unsigned long attrs)
+static void *dma_direct_alloc(struct device *dev, size_t size,
+		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	void *ret;
 
@@ -23,24 +22,21 @@ static void *dma_noop_alloc(struct device *dev, size_t size,
 	return ret;
 }
 
-static void dma_noop_free(struct device *dev, size_t size,
-			  void *cpu_addr, dma_addr_t dma_addr,
-			  unsigned long attrs)
+static void dma_direct_free(struct device *dev, size_t size, void *cpu_addr,
+		dma_addr_t dma_addr, unsigned long attrs)
 {
 	free_pages((unsigned long)cpu_addr, get_order(size));
 }
 
-static dma_addr_t dma_noop_map_page(struct device *dev, struct page *page,
-				      unsigned long offset, size_t size,
-				      enum dma_data_direction dir,
-				      unsigned long attrs)
+static dma_addr_t dma_direct_map_page(struct device *dev, struct page *page,
+		unsigned long offset, size_t size, enum dma_data_direction dir,
+		unsigned long attrs)
 {
 	return page_to_phys(page) + offset - PFN_PHYS(dev->dma_pfn_offset);
 }
 
-static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nents,
-			     enum dma_data_direction dir,
-			     unsigned long attrs)
+static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl,
+		int nents, enum dma_data_direction dir, unsigned long attrs)
 {
 	int i;
 	struct scatterlist *sg;
@@ -58,11 +54,10 @@ static int dma_noop_map_sg(struct device *dev, struct scatterlist *sgl, int nent
 	return nents;
 }
 
-const struct dma_map_ops dma_noop_ops = {
-	.alloc			= dma_noop_alloc,
-	.free			= dma_noop_free,
-	.map_page		= dma_noop_map_page,
-	.map_sg			= dma_noop_map_sg,
+const struct dma_map_ops dma_direct_ops = {
+	.alloc			= dma_direct_alloc,
+	.free			= dma_direct_free,
+	.map_page		= dma_direct_map_page,
+	.map_sg			= dma_direct_map_sg,
 };
-
-EXPORT_SYMBOL(dma_noop_ops);
+EXPORT_SYMBOL(dma_direct_ops);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 22/33] dma-mapping: provide a generic asm/dma-mapping.h
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

For architectures that just use the generic dma_noop_ops we can provide
a generic version of dma-mapping.h.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 MAINTAINERS                          |  1 +
 arch/m32r/include/asm/Kbuild         |  1 +
 arch/m32r/include/asm/dma-mapping.h  | 17 -----------------
 arch/riscv/include/asm/Kbuild        |  1 +
 arch/riscv/include/asm/dma-mapping.h | 30 ------------------------------
 arch/s390/include/asm/Kbuild         |  1 +
 arch/s390/include/asm/dma-mapping.h  | 17 -----------------
 include/asm-generic/dma-mapping.h    | 10 ++++++++++
 8 files changed, 14 insertions(+), 64 deletions(-)
 delete mode 100644 arch/m32r/include/asm/dma-mapping.h
 delete mode 100644 arch/riscv/include/asm/dma-mapping.h
 delete mode 100644 arch/s390/include/asm/dma-mapping.h
 create mode 100644 include/asm-generic/dma-mapping.h

diff --git a/MAINTAINERS b/MAINTAINERS
index d2cfdcce1db5..234e642e7149 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4338,6 +4338,7 @@ F:	lib/dma-noop.c
 F:	lib/dma-virt.c
 F:	drivers/base/dma-mapping.c
 F:	drivers/base/dma-coherent.c
+F:	include/asm-generic/dma-mapping.h
 F:	include/linux/dma-direct.h
 F:	include/linux/dma-mapping.h
 
diff --git a/arch/m32r/include/asm/Kbuild b/arch/m32r/include/asm/Kbuild
index 7e11b125c35e..ca83fda8177b 100644
--- a/arch/m32r/include/asm/Kbuild
+++ b/arch/m32r/include/asm/Kbuild
@@ -1,5 +1,6 @@
 generic-y += clkdev.h
 generic-y += current.h
+generic-y += dma-mapping.h
 generic-y += exec.h
 generic-y += extable.h
 generic-y += irq_work.h
diff --git a/arch/m32r/include/asm/dma-mapping.h b/arch/m32r/include/asm/dma-mapping.h
deleted file mode 100644
index 8967fb659691..000000000000
--- a/arch/m32r/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_M32R_DMA_MAPPING_H
-#define _ASM_M32R_DMA_MAPPING_H
-
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/mm.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-debug.h>
-#include <linux/io.h>
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &dma_noop_ops;
-}
-
-#endif /* _ASM_M32R_DMA_MAPPING_H */
diff --git a/arch/riscv/include/asm/Kbuild b/arch/riscv/include/asm/Kbuild
index 970460a0b492..197460ccbf21 100644
--- a/arch/riscv/include/asm/Kbuild
+++ b/arch/riscv/include/asm/Kbuild
@@ -7,6 +7,7 @@ generic-y += device.h
 generic-y += div64.h
 generic-y += dma.h
 generic-y += dma-contiguous.h
+generic-y += dma-mapping.h
 generic-y += emergency-restart.h
 generic-y += errno.h
 generic-y += exec.h
diff --git a/arch/riscv/include/asm/dma-mapping.h b/arch/riscv/include/asm/dma-mapping.h
deleted file mode 100644
index 73849e2cc761..000000000000
--- a/arch/riscv/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Copyright (C) 2003-2004 Hewlett-Packard Co
- *	David Mosberger-Tang <davidm@hpl.hp.com>
- * Copyright (C) 2012 ARM Ltd.
- * Copyright (C) 2016 SiFive, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- */
-#ifndef __ASM_RISCV_DMA_MAPPING_H
-#define __ASM_RISCV_DMA_MAPPING_H
-
-/* Use ops->dma_mapping_error (if it exists) or assume success */
-// #undef DMA_ERROR_CODE
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &dma_noop_ops;
-}
-
-#endif	/* __ASM_RISCV_DMA_MAPPING_H */
diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild
index 048450869328..dade72be127b 100644
--- a/arch/s390/include/asm/Kbuild
+++ b/arch/s390/include/asm/Kbuild
@@ -4,6 +4,7 @@ generic-y += cacheflush.h
 generic-y += clkdev.h
 generic-y += device.h
 generic-y += dma-contiguous.h
+generic-y += dma-mapping.h
 generic-y += div64.h
 generic-y += emergency-restart.h
 generic-y += export.h
diff --git a/arch/s390/include/asm/dma-mapping.h b/arch/s390/include/asm/dma-mapping.h
deleted file mode 100644
index bdc2455483f6..000000000000
--- a/arch/s390/include/asm/dma-mapping.h
+++ /dev/null
@@ -1,17 +0,0 @@
-/* SPDX-License-Identifier: GPL-2.0 */
-#ifndef _ASM_S390_DMA_MAPPING_H
-#define _ASM_S390_DMA_MAPPING_H
-
-#include <linux/kernel.h>
-#include <linux/types.h>
-#include <linux/mm.h>
-#include <linux/scatterlist.h>
-#include <linux/dma-debug.h>
-#include <linux/io.h>
-
-static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
-{
-	return &dma_noop_ops;
-}
-
-#endif /* _ASM_S390_DMA_MAPPING_H */
diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h
new file mode 100644
index 000000000000..164031531d85
--- /dev/null
+++ b/include/asm-generic/dma-mapping.h
@@ -0,0 +1,10 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_GENERIC_DMA_MAPPING_H
+#define _ASM_GENERIC_DMA_MAPPING_H
+
+static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
+{
+	return &dma_noop_ops;
+}
+
+#endif /* _ASM_GENERIC_DMA_MAPPING_H */
-- 
2.14.2

^ permalink raw reply related

* [PATCH 21/33] dma-mapping: add an arch_dma_supported hook
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

To implement the x86 forbid_dac and iommu_sac_force we want an arch hook
so that it can apply the global options across all dma_map_ops
implementations.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/x86/include/asm/dma-mapping.h |  3 +++
 arch/x86/kernel/pci-dma.c          | 19 ++++++++++++-------
 include/linux/dma-mapping.h        | 11 +++++++++++
 3 files changed, 26 insertions(+), 7 deletions(-)

diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index dfdc9357a349..6277c83c0eb1 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -30,6 +30,9 @@ static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 	return dma_ops;
 }
 
+int arch_dma_supported(struct device *dev, u64 mask);
+#define arch_dma_supported arch_dma_supported
+
 bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp);
 #define arch_dma_alloc_attrs arch_dma_alloc_attrs
 
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 61a8f1cb3829..df7ab02f959f 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -215,7 +215,7 @@ static __init int iommu_setup(char *p)
 }
 early_param("iommu", iommu_setup);
 
-int x86_dma_supported(struct device *dev, u64 mask)
+int arch_dma_supported(struct device *dev, u64 mask)
 {
 #ifdef CONFIG_PCI
 	if (mask > 0xffffffff && forbid_dac > 0) {
@@ -224,12 +224,6 @@ int x86_dma_supported(struct device *dev, u64 mask)
 	}
 #endif
 
-	/* Copied from i386. Doesn't make much sense, because it will
-	   only work for pci_alloc_coherent.
-	   The caller just has to use GFP_DMA in this case. */
-	if (mask < DMA_BIT_MASK(24))
-		return 0;
-
 	/* Tell the device to use SAC when IOMMU force is on.  This
 	   allows the driver to use cheaper accesses in some cases.
 
@@ -249,6 +243,17 @@ int x86_dma_supported(struct device *dev, u64 mask)
 
 	return 1;
 }
+EXPORT_SYMBOL(arch_dma_supported);
+
+int x86_dma_supported(struct device *dev, u64 mask)
+{
+	/* Copied from i386. Doesn't make much sense, because it will
+	   only work for pci_alloc_coherent.
+	   The caller just has to use GFP_DMA in this case. */
+	if (mask < DMA_BIT_MASK(24))
+		return 0;
+	return 1;
+}
 
 static int __init pci_iommu_init(void)
 {
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 88bcb1a8211d..d67742dad904 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -576,6 +576,14 @@ static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
 	return 0;
 }
 
+/*
+ * This is a hack for the legacy x86 forbid_dac and iommu_sac_force. Please
+ * don't use this is new code.
+ */
+#ifndef arch_dma_supported
+#define arch_dma_supported(dev, mask)	(1)
+#endif
+
 static inline void dma_check_mask(struct device *dev, u64 mask)
 {
 	if (sme_active() && (mask < (((u64)sme_get_me_mask() << 1) - 1)))
@@ -588,6 +596,9 @@ static inline int dma_supported(struct device *dev, u64 mask)
 
 	if (!ops)
 		return 0;
+	if (!arch_dma_supported(dev, mask))
+		return 0;
+
 	if (!ops->dma_supported)
 		return 1;
 	return ops->dma_supported(dev, mask);
-- 
2.14.2

^ permalink raw reply related

* [PATCH 20/33] dma-mapping: clear harmful GFP_* flags in common code
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Lift the code from x86 so that we behave consistently.  In the future we
should probably warn if any of these is set.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jesper Nilsson <jesper.nilsson@axis.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> [m68k]
---
 arch/cris/arch-v32/drivers/pci/dma.c      | 3 ---
 arch/h8300/kernel/dma.c                   | 3 ---
 arch/m68k/kernel/dma.c                    | 2 --
 arch/mips/cavium-octeon/dma-octeon.c      | 3 ---
 arch/mips/loongson64/common/dma-swiotlb.c | 3 ---
 arch/mips/mm/dma-default.c                | 3 ---
 arch/mips/netlogic/common/nlm-dma.c       | 3 ---
 arch/mn10300/mm/dma-alloc.c               | 3 ---
 arch/nios2/mm/dma-mapping.c               | 3 ---
 arch/powerpc/kernel/dma.c                 | 3 ---
 arch/x86/kernel/pci-dma.c                 | 2 --
 include/linux/dma-mapping.h               | 7 +++++++
 12 files changed, 7 insertions(+), 31 deletions(-)

diff --git a/arch/cris/arch-v32/drivers/pci/dma.c b/arch/cris/arch-v32/drivers/pci/dma.c
index dbbd3816cc0b..8c3802244ef3 100644
--- a/arch/cris/arch-v32/drivers/pci/dma.c
+++ b/arch/cris/arch-v32/drivers/pci/dma.c
@@ -22,9 +22,6 @@ static void *v32_dma_alloc(struct device *dev, size_t size,
 {
 	void *ret;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
 	if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
 		gfp |= GFP_DMA;
 
diff --git a/arch/h8300/kernel/dma.c b/arch/h8300/kernel/dma.c
index 225dd0a188dc..d44ba5db4ac3 100644
--- a/arch/h8300/kernel/dma.c
+++ b/arch/h8300/kernel/dma.c
@@ -16,9 +16,6 @@ static void *dma_alloc(struct device *dev, size_t size,
 {
 	void *ret;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
 	if (dev == NULL || (*dev->dma_mask < 0xffffffff))
 		gfp |= GFP_DMA;
 	ret = (void *)__get_free_pages(gfp, get_order(size));
diff --git a/arch/m68k/kernel/dma.c b/arch/m68k/kernel/dma.c
index 87ef73a93856..c01b9b8f97bf 100644
--- a/arch/m68k/kernel/dma.c
+++ b/arch/m68k/kernel/dma.c
@@ -76,8 +76,6 @@ static void *m68k_dma_alloc(struct device *dev, size_t size,
 		dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
 	void *ret;
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
 
 	if (dev == NULL || (*dev->dma_mask < 0xffffffff))
 		gfp |= GFP_DMA;
diff --git a/arch/mips/cavium-octeon/dma-octeon.c b/arch/mips/cavium-octeon/dma-octeon.c
index c64bd87f0b6e..5baf79fce643 100644
--- a/arch/mips/cavium-octeon/dma-octeon.c
+++ b/arch/mips/cavium-octeon/dma-octeon.c
@@ -161,9 +161,6 @@ static void *octeon_dma_alloc_coherent(struct device *dev, size_t size,
 {
 	void *ret;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
 	if (IS_ENABLED(CONFIG_ZONE_DMA) && dev == NULL)
 		gfp |= __GFP_DMA;
 	else if (IS_ENABLED(CONFIG_ZONE_DMA) &&
diff --git a/arch/mips/loongson64/common/dma-swiotlb.c b/arch/mips/loongson64/common/dma-swiotlb.c
index ef07740cee61..15388c24a504 100644
--- a/arch/mips/loongson64/common/dma-swiotlb.c
+++ b/arch/mips/loongson64/common/dma-swiotlb.c
@@ -15,9 +15,6 @@ static void *loongson_dma_alloc_coherent(struct device *dev, size_t size,
 {
 	void *ret;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
 	if ((IS_ENABLED(CONFIG_ISA) && dev == NULL) ||
 	    (IS_ENABLED(CONFIG_ZONE_DMA) &&
 	     dev->coherent_dma_mask < DMA_BIT_MASK(32)))
diff --git a/arch/mips/mm/dma-default.c b/arch/mips/mm/dma-default.c
index e3e94d05f0fd..237532e89919 100644
--- a/arch/mips/mm/dma-default.c
+++ b/arch/mips/mm/dma-default.c
@@ -93,9 +93,6 @@ static gfp_t massage_gfp_flags(const struct device *dev, gfp_t gfp)
 {
 	gfp_t dma_flag;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
 #ifdef CONFIG_ISA
 	if (dev == NULL)
 		dma_flag = __GFP_DMA;
diff --git a/arch/mips/netlogic/common/nlm-dma.c b/arch/mips/netlogic/common/nlm-dma.c
index 0ec9d9da6d51..49c975b6aa28 100644
--- a/arch/mips/netlogic/common/nlm-dma.c
+++ b/arch/mips/netlogic/common/nlm-dma.c
@@ -47,9 +47,6 @@ static char *nlm_swiotlb;
 static void *nlm_dma_alloc_coherent(struct device *dev, size_t size,
 	dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
 {
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM);
-
 #ifdef CONFIG_ZONE_DMA32
 	if (dev->coherent_dma_mask <= DMA_BIT_MASK(32))
 		gfp |= __GFP_DMA32;
diff --git a/arch/mn10300/mm/dma-alloc.c b/arch/mn10300/mm/dma-alloc.c
index 86108d2496b3..e3910d4db102 100644
--- a/arch/mn10300/mm/dma-alloc.c
+++ b/arch/mn10300/mm/dma-alloc.c
@@ -37,9 +37,6 @@ static void *mn10300_dma_alloc(struct device *dev, size_t size,
 		goto done;
 	}
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
 	if (dev == NULL || dev->coherent_dma_mask < 0xffffffff)
 		gfp |= GFP_DMA;
 
diff --git a/arch/nios2/mm/dma-mapping.c b/arch/nios2/mm/dma-mapping.c
index 7040c1adbb5e..4be815519dd4 100644
--- a/arch/nios2/mm/dma-mapping.c
+++ b/arch/nios2/mm/dma-mapping.c
@@ -63,9 +63,6 @@ static void *nios2_dma_alloc(struct device *dev, size_t size,
 {
 	void *ret;
 
-	/* ignore region specifiers */
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
-
 	/* optimized page clearing */
 	gfp |= __GFP_ZERO;
 
diff --git a/arch/powerpc/kernel/dma.c b/arch/powerpc/kernel/dma.c
index 6d5d04ccf3b4..76079841d3d0 100644
--- a/arch/powerpc/kernel/dma.c
+++ b/arch/powerpc/kernel/dma.c
@@ -105,9 +105,6 @@ void *__dma_nommu_alloc_coherent(struct device *dev, size_t size,
 	};
 #endif /* CONFIG_FSL_SOC */
 
-	/* ignore region specifiers */
-	flag  &= ~(__GFP_HIGHMEM);
-
 	page = alloc_pages_node(node, flag, get_order(size));
 	if (page == NULL)
 		return NULL;
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 8439e6de6156..61a8f1cb3829 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -87,7 +87,6 @@ void *dma_generic_alloc_coherent(struct device *dev, size_t size,
 
 	dma_mask = dma_alloc_coherent_mask(dev, flag);
 
-	flag &= ~__GFP_ZERO;
 again:
 	page = NULL;
 	/* CMA can be used only in the context which permits sleeping */
@@ -139,7 +138,6 @@ bool arch_dma_alloc_attrs(struct device **dev, gfp_t *gfp)
 	if (!*dev)
 		*dev = &x86_dma_fallback_dev;
 
-	*gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
 	*gfp = dma_alloc_coherent_gfp_flags(*dev, *gfp);
 
 	if (!is_device_dma_capable(*dev))
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 9f28b2fa329e..88bcb1a8211d 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -518,6 +518,13 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 	if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
 		return cpu_addr;
 
+	/*
+	 * Let the implementation decide on the zone to allocate from, and
+	 * decide on the way of zeroing the memory given that the memory
+	 * returned should always be zeroed.
+	 */
+	flag &= ~(__GFP_DMA | __GFP_DMA32 | __GFP_HIGHMEM | __GFP_ZERO);
+
 	if (!arch_dma_alloc_attrs(&dev, &flag))
 		return NULL;
 	if (!ops->alloc)
-- 
2.14.2

^ permalink raw reply related

* [PATCH 19/33] dma-mapping: warn when there is no coherent_dma_mask
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

These days all devices should have a DMA coherent mask, and most dma_ops
implementations rely on that fact.  But just to be sure add an assert to
ring the warning bell if that is not the case.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 include/linux/dma-mapping.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index d84951865be7..9f28b2fa329e 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -513,6 +513,7 @@ static inline void *dma_alloc_attrs(struct device *dev, size_t size,
 	void *cpu_addr;
 
 	BUG_ON(!ops);
+	WARN_ON_ONCE(!dev->coherent_dma_mask);
 
 	if (dma_alloc_from_dev_coherent(dev, size, dma_handle, &cpu_addr))
 		return cpu_addr;
-- 
2.14.2

^ permalink raw reply related

* [PATCH 18/33] s390: move s390_pci_dma_ops to asm/pci_dma.h
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

This is not needed in drivers, so move it to a private header.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/s390/include/asm/dma-mapping.h | 2 --
 arch/s390/include/asm/pci_dma.h     | 3 +++
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/s390/include/asm/dma-mapping.h b/arch/s390/include/asm/dma-mapping.h
index 2ec7240c1ada..bdc2455483f6 100644
--- a/arch/s390/include/asm/dma-mapping.h
+++ b/arch/s390/include/asm/dma-mapping.h
@@ -9,8 +9,6 @@
 #include <linux/dma-debug.h>
 #include <linux/io.h>
 
-extern const struct dma_map_ops s390_pci_dma_ops;
-
 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
 {
 	return &dma_noop_ops;
diff --git a/arch/s390/include/asm/pci_dma.h b/arch/s390/include/asm/pci_dma.h
index e8d9161fa17a..419fac7a62c0 100644
--- a/arch/s390/include/asm/pci_dma.h
+++ b/arch/s390/include/asm/pci_dma.h
@@ -201,4 +201,7 @@ void dma_cleanup_tables(unsigned long *);
 unsigned long *dma_walk_cpu_trans(unsigned long *rto, dma_addr_t dma_addr);
 void dma_update_cpu_trans(unsigned long *entry, void *page_addr, int flags);
 
+extern const struct dma_map_ops s390_pci_dma_ops;
+
+
 #endif
-- 
2.14.2

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* [PATCH 17/33] microblaze: remove the dead !NOT_COHERENT_CACHE dma code
From: Christoph Hellwig @ 2018-01-10  8:00 UTC (permalink / raw)
  To: iommu
  Cc: Konrad Rzeszutek Wilk, linux-alpha, linux-snps-arc,
	linux-arm-kernel, linux-c6x-dev, linux-cris-kernel, linux-hexagon,
	linux-ia64, linux-m68k, linux-metag, Michal Simek, linux-mips,
	linux-parisc, linuxppc-dev, patches, linux-s390, linux-sh,
	sparclinux, Guan Xuetao, x86, linux-arch, linux-kernel
In-Reply-To: <20180110080027.13879-1-hch@lst.de>

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 arch/microblaze/kernel/dma.c | 28 ----------------------------
 1 file changed, 28 deletions(-)

diff --git a/arch/microblaze/kernel/dma.c b/arch/microblaze/kernel/dma.c
index b45d8f8967af..c91e8cef98dd 100644
--- a/arch/microblaze/kernel/dma.c
+++ b/arch/microblaze/kernel/dma.c
@@ -15,42 +15,18 @@
 #include <linux/bug.h>
 #include <asm/cacheflush.h>
 
-#define NOT_COHERENT_CACHE
-
 static void *dma_nommu_alloc_coherent(struct device *dev, size_t size,
 				       dma_addr_t *dma_handle, gfp_t flag,
 				       unsigned long attrs)
 {
-#ifdef NOT_COHERENT_CACHE
 	return consistent_alloc(flag, size, dma_handle);
-#else
-	void *ret;
-	struct page *page;
-	int node = dev_to_node(dev);
-
-	/* ignore region specifiers */
-	flag  &= ~(__GFP_HIGHMEM);
-
-	page = alloc_pages_node(node, flag, get_order(size));
-	if (page == NULL)
-		return NULL;
-	ret = page_address(page);
-	memset(ret, 0, size);
-	*dma_handle = virt_to_phys(ret);
-
-	return ret;
-#endif
 }
 
 static void dma_nommu_free_coherent(struct device *dev, size_t size,
 				     void *vaddr, dma_addr_t dma_handle,
 				     unsigned long attrs)
 {
-#ifdef NOT_COHERENT_CACHE
 	consistent_free(size, vaddr);
-#else
-	free_pages((unsigned long)vaddr, get_order(size));
-#endif
 }
 
 static inline void __dma_sync(unsigned long paddr,
@@ -186,12 +162,8 @@ int dma_nommu_mmap_coherent(struct device *dev, struct vm_area_struct *vma,
 	if (off >= count || user_count > (count - off))
 		return -ENXIO;
 
-#ifdef NOT_COHERENT_CACHE
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
 	pfn = consistent_virt_to_pfn(cpu_addr);
-#else
-	pfn = virt_to_pfn(cpu_addr);
-#endif
 	return remap_pfn_range(vma, vma->vm_start, pfn + off,
 			       vma->vm_end - vma->vm_start, vma->vm_page_prot);
 #else
-- 
2.14.2

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