[PATCH 0/4] deinline some DMA functions

[PATCH 0/4] deinline some DMA functions

[Denys Vlasenko]

Collectively, deinlining these four functions reduces
vmlinux by 215665 bytes on allyesconfig build:

   text	     data      bss       dec     hex filename
82662736 22255384 20627456 125545576 77bac68 vmlinux0
82447071 22255384 20627456 125329911 77861f7 vmlinux4

Denys Vlasenko (4):
  x86: deinline dma_alloc_attrs()
  x86: deinline dma_free_attrs()
  deinline dma_map_single_attrs()
  deinline dma_unmap_single_attrs()

 arch/x86/include/asm/dma-mapping.h       | 46 ++++---------------------------
 arch/x86/kernel/pci-dma.c                | 45 ++++++++++++++++++++++++++++++
 include/asm-generic/dma-mapping-common.h | 40 ++++++---------------------
 kernel/Makefile                          |  3 +-
 kernel/dma-mapping-common.c              | 47 ++++++++++++++++++++++++++++++++
 5 files changed, 108 insertions(+), 73 deletions(-)
 create mode 100644 kernel/dma-mapping-common.c

-- 
1.8.1.4

[PATCH 1/4] x86: deinline dma_alloc_attrs()

[Denys Vlasenko]

Reduces kernel size by 68739 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82662736 22255384 20627456 125545576 77bac68 vmlinux0
82594029 22255352 20627456 125476837 77a9fe5 vmlinux1

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
---
 arch/x86/include/asm/dma-mapping.h | 28 ++--------------------------
 arch/x86/kernel/pci-dma.c          | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 26 deletions(-)

diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 808dae6..6339320 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -127,33 +127,9 @@ static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 
 #define dma_alloc_coherent(d,s,h,f)	dma_alloc_attrs(d,s,h,f,NULL)
 
-static inline void *
+void *
 dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	void *memory;
-
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-
-	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
-		return memory;
-
-	if (!dev)
-		dev = &x86_dma_fallback_dev;
-
-	if (!is_device_dma_capable(dev))
-		return NULL;
-
-	if (!ops->alloc)
-		return NULL;
-
-	memory = ops->alloc(dev, size, dma_handle,
-			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
-	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
-
-	return memory;
-}
+		gfp_t gfp, struct dma_attrs *attrs);
 
 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index a25e202..f9f7656 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -140,6 +140,34 @@ void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
 		free_pages((unsigned long)vaddr, get_order(size));
 }
 
+void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		      gfp_t gfp, struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+	void *memory;
+
+	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+
+	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
+		return memory;
+
+	if (!dev)
+		dev = &x86_dma_fallback_dev;
+
+	if (!is_device_dma_capable(dev))
+		return NULL;
+
+	if (!ops->alloc)
+		return NULL;
+
+	memory = ops->alloc(dev, size, dma_handle,
+			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
+	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
+
+	return memory;
+}
+EXPORT_SYMBOL(dma_alloc_attrs);
+
 /*
  * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
  * parameter documentation.
-- 
1.8.1.4

[PATCH 2/4] x86: deinline dma_free_attrs()

[Denys Vlasenko]

Reduces kernel size by 76720 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82594029 22255352 20627456 125476837 77a9fe5 vmlinux1
82517277 22255384 20627456 125400117 7797435 vmlinux2

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: x86@kernel.org
Cc: linux-kernel@vger.kernel.org
---
 arch/x86/include/asm/dma-mapping.h | 18 +++---------------
 arch/x86/kernel/pci-dma.c          | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 6339320..1f5b728 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -133,20 +133,8 @@ dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 
 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 
-static inline void dma_free_attrs(struct device *dev, size_t size,
-				  void *vaddr, dma_addr_t bus,
-				  struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-
-	WARN_ON(irqs_disabled());       /* for portability */
-
-	if (dma_release_from_coherent(dev, get_order(size), vaddr))
-		return;
-
-	debug_dma_free_coherent(dev, size, vaddr, bus);
-	if (ops->free)
-		ops->free(dev, size, vaddr, bus, attrs);
-}
+void dma_free_attrs(struct device *dev, size_t size,
+		    void *vaddr, dma_addr_t bus,
+		    struct dma_attrs *attrs);
 
 #endif
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index f9f7656..353972c 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -168,6 +168,23 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 }
 EXPORT_SYMBOL(dma_alloc_attrs);
 
+void dma_free_attrs(struct device *dev, size_t size,
+		    void *vaddr, dma_addr_t bus,
+		    struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+
+	WARN_ON(irqs_disabled());       /* for portability */
+
+	if (dma_release_from_coherent(dev, get_order(size), vaddr))
+		return;
+
+	debug_dma_free_coherent(dev, size, vaddr, bus);
+	if (ops->free)
+		ops->free(dev, size, vaddr, bus, attrs);
+}
+EXPORT_SYMBOL(dma_free_attrs);
+
 /*
  * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
  * parameter documentation.
-- 
1.8.1.4

[PATCH 3/4] deinline dma_map_single_attrs()

[Denys Vlasenko]

Reduces kernel size by 43259 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82517277 22255384 20627456 125400117 7797435 vmlinux2
82474018 22255384 20627456 125356858 778cb3a vmlinux3

I did not find a suitable .c file to move this function to,
so I added a new one, kernel/dma-mapping-common.c

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: linux-kernel@vger.kernel.org
---
 include/asm-generic/dma-mapping-common.h | 22 ++++-----------------
 kernel/Makefile                          |  3 ++-
 kernel/dma-mapping-common.c              | 33 ++++++++++++++++++++++++++++++++
 3 files changed, 39 insertions(+), 19 deletions(-)
 create mode 100644 kernel/dma-mapping-common.c

diff --git a/include/asm-generic/dma-mapping-common.h b/include/asm-generic/dma-mapping-common.h
index 3378dcf..688f86b 100644
--- a/include/asm-generic/dma-mapping-common.h
+++ b/include/asm-generic/dma-mapping-common.h
@@ -7,24 +7,10 @@
 #include <linux/dma-debug.h>
 #include <linux/dma-attrs.h>
 
-static inline dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
-					      size_t size,
-					      enum dma_data_direction dir,
-					      struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	dma_addr_t addr;
-
-	kmemcheck_mark_initialized(ptr, size);
-	BUG_ON(!valid_dma_direction(dir));
-	addr = ops->map_page(dev, virt_to_page(ptr),
-			     (unsigned long)ptr & ~PAGE_MASK, size,
-			     dir, attrs);
-	debug_dma_map_page(dev, virt_to_page(ptr),
-			   (unsigned long)ptr & ~PAGE_MASK, size,
-			   dir, addr, true);
-	return addr;
-}
+dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
+				size_t size,
+				enum dma_data_direction dir,
+				struct dma_attrs *attrs);
 
 static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
 					  size_t size,
diff --git a/kernel/Makefile b/kernel/Makefile
index 1408b33..8c8b683 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -9,7 +9,8 @@ obj-y     = fork.o exec_domain.o panic.o \
 	    extable.o params.o \
 	    kthread.o sys_ni.o nsproxy.o \
 	    notifier.o ksysfs.o cred.o reboot.o \
-	    async.o range.o groups.o smpboot.o
+	    async.o range.o groups.o smpboot.o \
+	    dma-mapping-common.o
 
 ifdef CONFIG_FUNCTION_TRACER
 # Do not trace debug files and internal ftrace files
diff --git a/kernel/dma-mapping-common.c b/kernel/dma-mapping-common.c
new file mode 100644
index 0000000..17457a4
--- /dev/null
+++ b/kernel/dma-mapping-common.c
@@ -0,0 +1,33 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; version 2
+ * of the License.
+ *
+ * This program is distributed in the hope that it would 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.
+ */
+#include <linux/dma-mapping.h>
+#include <asm-generic/dma-mapping-common.h>
+
+dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
+		size_t size,
+		enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+	dma_addr_t addr;
+
+	kmemcheck_mark_initialized(ptr, size);
+	BUG_ON(!valid_dma_direction(dir));
+	addr = ops->map_page(dev, virt_to_page(ptr),
+			     (unsigned long)ptr & ~PAGE_MASK, size,
+			     dir, attrs);
+	debug_dma_map_page(dev, virt_to_page(ptr),
+			   (unsigned long)ptr & ~PAGE_MASK, size,
+			   dir, addr, true);
+	return addr;
+}
+EXPORT_SYMBOL(dma_map_single_attrs);
-- 
1.8.1.4

[PATCH 4/4] deinline dma_unmap_single_attrs()

[Denys Vlasenko]

Reduces kernel size by 26947 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82474018 22255384 20627456 125356858 778cb3a vmlinux3
82447071 22255384 20627456 125329911 77861f7 vmlinux4

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: linux-kernel@vger.kernel.org
---
 include/asm-generic/dma-mapping-common.h | 16 ++++------------
 kernel/dma-mapping-common.c              | 14 ++++++++++++++
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/include/asm-generic/dma-mapping-common.h b/include/asm-generic/dma-mapping-common.h
index 688f86b..0684d9c 100644
--- a/include/asm-generic/dma-mapping-common.h
+++ b/include/asm-generic/dma-mapping-common.h
@@ -12,18 +12,10 @@ dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 				enum dma_data_direction dir,
 				struct dma_attrs *attrs);
 
-static inline void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
-					  size_t size,
-					  enum dma_data_direction dir,
-					  struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-
-	BUG_ON(!valid_dma_direction(dir));
-	if (ops->unmap_page)
-		ops->unmap_page(dev, addr, size, dir, attrs);
-	debug_dma_unmap_page(dev, addr, size, dir, true);
-}
+void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
+			    size_t size,
+			    enum dma_data_direction dir,
+			    struct dma_attrs *attrs);
 
 static inline int dma_map_sg_attrs(struct device *dev, struct scatterlist *sg,
 				   int nents, enum dma_data_direction dir,
diff --git a/kernel/dma-mapping-common.c b/kernel/dma-mapping-common.c
index 17457a4..75e514e 100644
--- a/kernel/dma-mapping-common.c
+++ b/kernel/dma-mapping-common.c
@@ -31,3 +31,17 @@ dma_addr_t dma_map_single_attrs(struct device *dev, void *ptr,
 	return addr;
 }
 EXPORT_SYMBOL(dma_map_single_attrs);
+
+void dma_unmap_single_attrs(struct device *dev, dma_addr_t addr,
+		size_t size,
+		enum dma_data_direction dir,
+		struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+
+	BUG_ON(!valid_dma_direction(dir));
+	if (ops->unmap_page)
+		ops->unmap_page(dev, addr, size, dir, attrs);
+	debug_dma_unmap_page(dev, addr, size, dir, true);
+}
+EXPORT_SYMBOL(dma_unmap_single_attrs);
-- 
1.8.1.4

[tip:x86/cleanups] x86: Deinline dma_alloc_attrs()

[tip-bot for Denys Vlasenko]

Commit-ID:  0c7965ff22472f60d5cf07308cb59f3a118feb8a
Gitweb:     http://git.kernel.org/tip/0c7965ff22472f60d5cf07308cb59f3a118feb8a
Author:     Denys Vlasenko <dvlasenk@redhat.com>
AuthorDate: Mon, 13 Apr 2015 13:54:32 +0200
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Tue, 5 May 2015 20:48:02 +0200

x86: Deinline dma_alloc_attrs()

Reduces kernel size by 68739 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82662736 22255384 20627456 125545576 77bac68 vmlinux0
82594029 22255352 20627456 125476837 77a9fe5 vmlinux1

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1428926075-28796-2-git-send-email-dvlasenk@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/include/asm/dma-mapping.h | 28 ++--------------------------
 arch/x86/kernel/pci-dma.c          | 28 ++++++++++++++++++++++++++++
 2 files changed, 30 insertions(+), 26 deletions(-)

diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 808dae6..6339320 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -127,33 +127,9 @@ static inline gfp_t dma_alloc_coherent_gfp_flags(struct device *dev, gfp_t gfp)
 
 #define dma_alloc_coherent(d,s,h,f)	dma_alloc_attrs(d,s,h,f,NULL)
 
-static inline void *
+void *
 dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
-		gfp_t gfp, struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-	void *memory;
-
-	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
-
-	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
-		return memory;
-
-	if (!dev)
-		dev = &x86_dma_fallback_dev;
-
-	if (!is_device_dma_capable(dev))
-		return NULL;
-
-	if (!ops->alloc)
-		return NULL;
-
-	memory = ops->alloc(dev, size, dma_handle,
-			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
-	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
-
-	return memory;
-}
+		gfp_t gfp, struct dma_attrs *attrs);
 
 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index a25e202..f9f7656 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -140,6 +140,34 @@ void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
 		free_pages((unsigned long)vaddr, get_order(size));
 }
 
+void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		      gfp_t gfp, struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+	void *memory;
+
+	gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+
+	if (dma_alloc_from_coherent(dev, size, dma_handle, &memory))
+		return memory;
+
+	if (!dev)
+		dev = &x86_dma_fallback_dev;
+
+	if (!is_device_dma_capable(dev))
+		return NULL;
+
+	if (!ops->alloc)
+		return NULL;
+
+	memory = ops->alloc(dev, size, dma_handle,
+			    dma_alloc_coherent_gfp_flags(dev, gfp), attrs);
+	debug_dma_alloc_coherent(dev, size, *dma_handle, memory);
+
+	return memory;
+}
+EXPORT_SYMBOL(dma_alloc_attrs);
+
 /*
  * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
  * parameter documentation.

[tip:x86/cleanups] x86: Deinline dma_free_attrs()

[tip-bot for Denys Vlasenko]

Commit-ID:  f1dc154f82595386cddcc7b980d8760474c3dd2d
Gitweb:     http://git.kernel.org/tip/f1dc154f82595386cddcc7b980d8760474c3dd2d
Author:     Denys Vlasenko <dvlasenk@redhat.com>
AuthorDate: Mon, 13 Apr 2015 13:54:33 +0200
Committer:  Thomas Gleixner <tglx@linutronix.de>
CommitDate: Tue, 5 May 2015 20:48:02 +0200

x86: Deinline dma_free_attrs()

Reduces kernel size by 76720 bytes on allyesconfig build:

    text     data      bss       dec     hex filename
82594029 22255352 20627456 125476837 77a9fe5 vmlinux1
82517277 22255384 20627456 125400117 7797435 vmlinux2

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Don Dutile <ddutile@redhat.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1428926075-28796-3-git-send-email-dvlasenk@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 arch/x86/include/asm/dma-mapping.h | 18 +++---------------
 arch/x86/kernel/pci-dma.c          | 17 +++++++++++++++++
 2 files changed, 20 insertions(+), 15 deletions(-)

diff --git a/arch/x86/include/asm/dma-mapping.h b/arch/x86/include/asm/dma-mapping.h
index 6339320..1f5b728 100644
--- a/arch/x86/include/asm/dma-mapping.h
+++ b/arch/x86/include/asm/dma-mapping.h
@@ -133,20 +133,8 @@ dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 
 #define dma_free_coherent(d,s,c,h) dma_free_attrs(d,s,c,h,NULL)
 
-static inline void dma_free_attrs(struct device *dev, size_t size,
-				  void *vaddr, dma_addr_t bus,
-				  struct dma_attrs *attrs)
-{
-	struct dma_map_ops *ops = get_dma_ops(dev);
-
-	WARN_ON(irqs_disabled());       /* for portability */
-
-	if (dma_release_from_coherent(dev, get_order(size), vaddr))
-		return;
-
-	debug_dma_free_coherent(dev, size, vaddr, bus);
-	if (ops->free)
-		ops->free(dev, size, vaddr, bus, attrs);
-}
+void dma_free_attrs(struct device *dev, size_t size,
+		    void *vaddr, dma_addr_t bus,
+		    struct dma_attrs *attrs);
 
 #endif
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index f9f7656..353972c 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -168,6 +168,23 @@ void *dma_alloc_attrs(struct device *dev, size_t size, dma_addr_t *dma_handle,
 }
 EXPORT_SYMBOL(dma_alloc_attrs);
 
+void dma_free_attrs(struct device *dev, size_t size,
+		    void *vaddr, dma_addr_t bus,
+		    struct dma_attrs *attrs)
+{
+	struct dma_map_ops *ops = get_dma_ops(dev);
+
+	WARN_ON(irqs_disabled());       /* for portability */
+
+	if (dma_release_from_coherent(dev, get_order(size), vaddr))
+		return;
+
+	debug_dma_free_coherent(dev, size, vaddr, bus);
+	if (ops->free)
+		ops->free(dev, size, vaddr, bus, attrs);
+}
+EXPORT_SYMBOL(dma_free_attrs);
+
 /*
  * See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
  * parameter documentation.