19 files changed, 340 insertions, 41 deletions

diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild
index be648eb47cd9..bd425302c97a 100644
--- a/arch/arm/include/asm/Kbuild
+++ b/arch/arm/include/asm/Kbuild
@@ -14,6 +14,7 @@ generic-y += local.h
 generic-y += local64.h
 generic-y += mm-arch-hooks.h
 generic-y += msgbuf.h
+generic-y += msi.h
 generic-y += param.h
 generic-y += parport.h
 generic-y += poll.h
diff --git a/arch/arm/include/asm/arch_gicv3.h b/arch/arm/include/asm/arch_gicv3.h
new file mode 100644
index 000000000000..6607d976e07d
--- /dev/null
+++ b/arch/arm/include/asm/arch_gicv3.h
@@ -0,0 +1,188 @@
+/*
+ * arch/arm/include/asm/arch_gicv3.h
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ *
+ * 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_ARCH_GICV3_H
+#define __ASM_ARCH_GICV3_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/io.h>
+
+#define __ACCESS_CP15(CRn, Op1, CRm, Op2)	p15, Op1, %0, CRn, CRm, Op2
+#define __ACCESS_CP15_64(Op1, CRm)		p15, Op1, %Q0, %R0, CRm
+
+#define ICC_EOIR1			__ACCESS_CP15(c12, 0, c12, 1)
+#define ICC_DIR				__ACCESS_CP15(c12, 0, c11, 1)
+#define ICC_IAR1			__ACCESS_CP15(c12, 0, c12, 0)
+#define ICC_SGI1R			__ACCESS_CP15_64(0, c12)
+#define ICC_PMR				__ACCESS_CP15(c4, 0, c6, 0)
+#define ICC_CTLR			__ACCESS_CP15(c12, 0, c12, 4)
+#define ICC_SRE				__ACCESS_CP15(c12, 0, c12, 5)
+#define ICC_IGRPEN1			__ACCESS_CP15(c12, 0, c12, 7)
+
+#define ICC_HSRE			__ACCESS_CP15(c12, 4, c9, 5)
+
+#define ICH_VSEIR			__ACCESS_CP15(c12, 4, c9, 4)
+#define ICH_HCR				__ACCESS_CP15(c12, 4, c11, 0)
+#define ICH_VTR				__ACCESS_CP15(c12, 4, c11, 1)
+#define ICH_MISR			__ACCESS_CP15(c12, 4, c11, 2)
+#define ICH_EISR			__ACCESS_CP15(c12, 4, c11, 3)
+#define ICH_ELSR			__ACCESS_CP15(c12, 4, c11, 5)
+#define ICH_VMCR			__ACCESS_CP15(c12, 4, c11, 7)
+
+#define __LR0(x)			__ACCESS_CP15(c12, 4, c12, x)
+#define __LR8(x)			__ACCESS_CP15(c12, 4, c13, x)
+
+#define ICH_LR0				__LR0(0)
+#define ICH_LR1				__LR0(1)
+#define ICH_LR2				__LR0(2)
+#define ICH_LR3				__LR0(3)
+#define ICH_LR4				__LR0(4)
+#define ICH_LR5				__LR0(5)
+#define ICH_LR6				__LR0(6)
+#define ICH_LR7				__LR0(7)
+#define ICH_LR8				__LR8(0)
+#define ICH_LR9				__LR8(1)
+#define ICH_LR10			__LR8(2)
+#define ICH_LR11			__LR8(3)
+#define ICH_LR12			__LR8(4)
+#define ICH_LR13			__LR8(5)
+#define ICH_LR14			__LR8(6)
+#define ICH_LR15			__LR8(7)
+
+/* LR top half */
+#define __LRC0(x)			__ACCESS_CP15(c12, 4, c14, x)
+#define __LRC8(x)			__ACCESS_CP15(c12, 4, c15, x)
+
+#define ICH_LRC0			__LRC0(0)
+#define ICH_LRC1			__LRC0(1)
+#define ICH_LRC2			__LRC0(2)
+#define ICH_LRC3			__LRC0(3)
+#define ICH_LRC4			__LRC0(4)
+#define ICH_LRC5			__LRC0(5)
+#define ICH_LRC6			__LRC0(6)
+#define ICH_LRC7			__LRC0(7)
+#define ICH_LRC8			__LRC8(0)
+#define ICH_LRC9			__LRC8(1)
+#define ICH_LRC10			__LRC8(2)
+#define ICH_LRC11			__LRC8(3)
+#define ICH_LRC12			__LRC8(4)
+#define ICH_LRC13			__LRC8(5)
+#define ICH_LRC14			__LRC8(6)
+#define ICH_LRC15			__LRC8(7)
+
+#define __AP0Rx(x)			__ACCESS_CP15(c12, 4, c8, x)
+#define ICH_AP0R0			__AP0Rx(0)
+#define ICH_AP0R1			__AP0Rx(1)
+#define ICH_AP0R2			__AP0Rx(2)
+#define ICH_AP0R3			__AP0Rx(3)
+
+#define __AP1Rx(x)			__ACCESS_CP15(c12, 4, c9, x)
+#define ICH_AP1R0			__AP1Rx(0)
+#define ICH_AP1R1			__AP1Rx(1)
+#define ICH_AP1R2			__AP1Rx(2)
+#define ICH_AP1R3			__AP1Rx(3)
+
+/* Low-level accessors */
+
+static inline void gic_write_eoir(u32 irq)
+{
+	asm volatile("mcr " __stringify(ICC_EOIR1) : : "r" (irq));
+	isb();
+}
+
+static inline void gic_write_dir(u32 val)
+{
+	asm volatile("mcr " __stringify(ICC_DIR) : : "r" (val));
+	isb();
+}
+
+static inline u32 gic_read_iar(void)
+{
+	u32 irqstat;
+
+	asm volatile("mrc " __stringify(ICC_IAR1) : "=r" (irqstat));
+	return irqstat;
+}
+
+static inline void gic_write_pmr(u32 val)
+{
+	asm volatile("mcr " __stringify(ICC_PMR) : : "r" (val));
+}
+
+static inline void gic_write_ctlr(u32 val)
+{
+	asm volatile("mcr " __stringify(ICC_CTLR) : : "r" (val));
+	isb();
+}
+
+static inline void gic_write_grpen1(u32 val)
+{
+	asm volatile("mcr " __stringify(ICC_IGRPEN1) : : "r" (val));
+	isb();
+}
+
+static inline void gic_write_sgi1r(u64 val)
+{
+	asm volatile("mcrr " __stringify(ICC_SGI1R) : : "r" (val));
+}
+
+static inline u32 gic_read_sre(void)
+{
+	u32 val;
+
+	asm volatile("mrc " __stringify(ICC_SRE) : "=r" (val));
+	return val;
+}
+
+static inline void gic_write_sre(u32 val)
+{
+	asm volatile("mcr " __stringify(ICC_SRE) : : "r" (val));
+	isb();
+}
+
+/*
+ * Even in 32bit systems that use LPAE, there is no guarantee that the I/O
+ * interface provides true 64bit atomic accesses, so using strd/ldrd doesn't
+ * make much sense.
+ * Moreover, 64bit I/O emulation is extremely difficult to implement on
+ * AArch32, since the syndrome register doesn't provide any information for
+ * them.
+ * Consequently, the following IO helpers use 32bit accesses.
+ *
+ * There are only two registers that need 64bit accesses in this driver:
+ * - GICD_IROUTERn, contain the affinity values associated to each interrupt.
+ *   The upper-word (aff3) will always be 0, so there is no need for a lock.
+ * - GICR_TYPER is an ID register and doesn't need atomicity.
+ */
+static inline void gic_write_irouter(u64 val, volatile void __iomem *addr)
+{
+	writel_relaxed((u32)val, addr);
+	writel_relaxed((u32)(val >> 32), addr + 4);
+}
+
+static inline u64 gic_read_typer(const volatile void __iomem *addr)
+{
+	u64 val;
+
+	val = readl_relaxed(addr);
+	val |= (u64)readl_relaxed(addr + 4) << 32;
+	return val;
+}
+
+#endif /* !__ASSEMBLY__ */
+#endif /* !__ASM_ARCH_GICV3_H */
diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h
index fe3ef397f5a4..9e10c4567eb4 100644
--- a/arch/arm/include/asm/atomic.h
+++ b/arch/arm/include/asm/atomic.h
@@ -27,8 +27,8 @@
  * strex/ldrex monitor on some implementations. The reason we can use it for
  * atomic_set() is the clrex or dummy strex done on every exception return.
  */
-#define atomic_read(v)	ACCESS_ONCE((v)->counter)
-#define atomic_set(v,i)	(((v)->counter) = (i))
+#define atomic_read(v)	READ_ONCE((v)->counter)
+#define atomic_set(v,i)	WRITE_ONCE(((v)->counter), (i))
 
 #if __LINUX_ARM_ARCH__ >= 6
 
@@ -210,8 +210,8 @@ ATOMIC_OP(xor, ^=, eor)
 
 #define atomic_inc_and_test(v)	(atomic_add_return(1, v) == 0)
 #define atomic_dec_and_test(v)	(atomic_sub_return(1, v) == 0)
-#define atomic_inc_return(v)    (atomic_add_return(1, v))
-#define atomic_dec_return(v)    (atomic_sub_return(1, v))
+#define atomic_inc_return_relaxed(v)    (atomic_add_return_relaxed(1, v))
+#define atomic_dec_return_relaxed(v)    (atomic_sub_return_relaxed(1, v))
 #define atomic_sub_and_test(i, v) (atomic_sub_return(i, v) == 0)
 
 #define atomic_add_negative(i,v) (atomic_add_return(i, v) < 0)
@@ -442,11 +442,11 @@ static inline int atomic64_add_unless(atomic64_t *v, long long a, long long u)
 
 #define atomic64_add_negative(a, v)	(atomic64_add_return((a), (v)) < 0)
 #define atomic64_inc(v)			atomic64_add(1LL, (v))
-#define atomic64_inc_return(v)		atomic64_add_return(1LL, (v))
+#define atomic64_inc_return_relaxed(v)	atomic64_add_return_relaxed(1LL, (v))
 #define atomic64_inc_and_test(v)	(atomic64_inc_return(v) == 0)
 #define atomic64_sub_and_test(a, v)	(atomic64_sub_return((a), (v)) == 0)
 #define atomic64_dec(v)			atomic64_sub(1LL, (v))
-#define atomic64_dec_return(v)		atomic64_sub_return(1LL, (v))
+#define atomic64_dec_return_relaxed(v)	atomic64_sub_return_relaxed(1LL, (v))
 #define atomic64_dec_and_test(v)	(atomic64_dec_return((v)) == 0)
 #define atomic64_inc_not_zero(v)	atomic64_add_unless((v), 1LL, 0LL)
 
diff --git a/arch/arm/include/asm/cmpxchg.h b/arch/arm/include/asm/cmpxchg.h
index 916a2744d5c6..97882f9bad12 100644
--- a/arch/arm/include/asm/cmpxchg.h
+++ b/arch/arm/include/asm/cmpxchg.h
@@ -39,6 +39,7 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 
 	switch (size) {
 #if __LINUX_ARM_ARCH__ >= 6
+#ifndef CONFIG_CPU_V6 /* MIN ARCH >= V6K */
 	case 1:
 		asm volatile("@	__xchg1\n"
 		"1:	ldrexb	%0, [%3]\n"
@@ -49,6 +50,17 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size
 			: "r" (x), "r" (ptr)
 			: "memory", "cc");
 		break;
+	case 2:
+		asm volatile("@	__xchg2\n"
+		"1:	ldrexh	%0, [%3]\n"
+		"	strexh	%1, %2, [%3]\n"
+		"	teq	%1, #0\n"
+		"	bne	1b"
+			: "=&r" (ret), "=&r" (tmp)
+			: "r" (x), "r" (ptr)
+			: "memory", "cc");
+		break;
+#endif
 	case 4:
 		asm volatile("@	__xchg4\n"
 		"1:	ldrex	%0, [%3]\n"
diff --git a/arch/arm/include/asm/hardware/cache-uniphier.h b/arch/arm/include/asm/hardware/cache-uniphier.h
new file mode 100644
index 000000000000..102e3fbe1e10
--- /dev/null
+++ b/arch/arm/include/asm/hardware/cache-uniphier.h
@@ -0,0 +1,46 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ */
+
+#ifndef __CACHE_UNIPHIER_H
+#define __CACHE_UNIPHIER_H
+
+#include <linux/types.h>
+
+#ifdef CONFIG_CACHE_UNIPHIER
+int uniphier_cache_init(void);
+int uniphier_cache_l2_is_enabled(void);
+void uniphier_cache_l2_touch_range(unsigned long start, unsigned long end);
+void uniphier_cache_l2_set_locked_ways(u32 way_mask);
+#else
+static inline int uniphier_cache_init(void)
+{
+	return -ENODEV;
+}
+
+static inline int uniphier_cache_l2_is_enabled(void)
+{
+	return 0;
+}
+
+static inline void uniphier_cache_l2_touch_range(unsigned long start,
+						 unsigned long end)
+{
+}
+
+static inline void uniphier_cache_l2_set_locked_ways(u32 way_mask)
+{
+}
+#endif
+
+#endif /* __CACHE_UNIPHIER_H */
diff --git a/arch/arm/include/asm/highmem.h b/arch/arm/include/asm/highmem.h
index 535579511ed0..0a0e2d1784c0 100644
--- a/arch/arm/include/asm/highmem.h
+++ b/arch/arm/include/asm/highmem.h
@@ -68,7 +68,6 @@ extern void kunmap(struct page *page);
 extern void *kmap_atomic(struct page *page);
 extern void __kunmap_atomic(void *kvaddr);
 extern void *kmap_atomic_pfn(unsigned long pfn);
-extern struct page *kmap_atomic_to_page(const void *ptr);
 #endif
 
 #endif
diff --git a/arch/arm/include/asm/irq.h b/arch/arm/include/asm/irq.h
index be1d07d59ee9..1bd9510de1b9 100644
--- a/arch/arm/include/asm/irq.h
+++ b/arch/arm/include/asm/irq.h
@@ -40,6 +40,11 @@ extern void arch_trigger_all_cpu_backtrace(bool);
 #define arch_trigger_all_cpu_backtrace(x) arch_trigger_all_cpu_backtrace(x)
 #endif
 
+static inline int nr_legacy_irqs(void)
+{
+	return NR_IRQS_LEGACY;
+}
+
 #endif
 
 #endif
diff --git a/arch/arm/include/asm/irqflags.h b/arch/arm/include/asm/irqflags.h
index 43908146a5cf..e6b70d9d084e 100644
--- a/arch/arm/include/asm/irqflags.h
+++ b/arch/arm/include/asm/irqflags.h
@@ -54,6 +54,14 @@ static inline void arch_local_irq_disable(void)
 
 #define local_fiq_enable()  __asm__("cpsie f	@ __stf" : : : "memory", "cc")
 #define local_fiq_disable() __asm__("cpsid f	@ __clf" : : : "memory", "cc")
+
+#ifndef CONFIG_CPU_V7M
+#define local_abt_enable()  __asm__("cpsie a	@ __sta" : : : "memory", "cc")
+#define local_abt_disable() __asm__("cpsid a	@ __cla" : : : "memory", "cc")
+#else
+#define local_abt_enable()	do { } while (0)
+#define local_abt_disable()	do { } while (0)
+#endif
 #else
 
 /*
@@ -136,6 +144,8 @@ static inline void arch_local_irq_disable(void)
 	: "memory", "cc");					\
 	})
 
+#define local_abt_enable()	do { } while (0)
+#define local_abt_disable()	do { } while (0)
 #endif
 
 /*
diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index d995821f1698..dc641ddf0784 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -218,4 +218,24 @@
 #define HSR_DABT_CM		(1U << 8)
 #define HSR_DABT_EA		(1U << 9)
 
+#define kvm_arm_exception_type	\
+	{0, "RESET" }, 		\
+	{1, "UNDEFINED" },	\
+	{2, "SOFTWARE" },	\
+	{3, "PREF_ABORT" },	\
+	{4, "DATA_ABORT" },	\
+	{5, "IRQ" },		\
+	{6, "FIQ" },		\
+	{7, "HVC" }
+
+#define HSRECN(x) { HSR_EC_##x, #x }
+
+#define kvm_arm_exception_class \
+	HSRECN(UNKNOWN), HSRECN(WFI), HSRECN(CP15_32), HSRECN(CP15_64), \
+	HSRECN(CP14_MR), HSRECN(CP14_LS), HSRECN(CP_0_13), HSRECN(CP10_ID), \
+	HSRECN(JAZELLE), HSRECN(BXJ), HSRECN(CP14_64), HSRECN(SVC_HYP), \
+	HSRECN(HVC), HSRECN(SMC), HSRECN(IABT), HSRECN(IABT_HYP), \
+	HSRECN(DABT), HSRECN(DABT_HYP)
+
+
 #endif /* __ARM_KVM_ARM_H__ */
diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index c4072d9f32c7..6692982c9b57 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -126,7 +126,10 @@ struct kvm_vcpu_arch {
 	 * here.
 	 */
 
-	/* Don't run the guest on this vcpu */
+	/* vcpu power-off state */
+	bool power_off;
+
+	 /* Don't run the guest (internal implementation need) */
 	bool pause;
 
 	/* IO related fields */
diff --git a/arch/arm/include/asm/mach/arch.h b/arch/arm/include/asm/mach/arch.h
index cb3a40717edd..5c1ad11aa392 100644
--- a/arch/arm/include/asm/mach/arch.h
+++ b/arch/arm/include/asm/mach/arch.h
@@ -47,7 +47,7 @@ struct machine_desc {
 	unsigned		l2c_aux_val;	/* L2 cache aux value	*/
 	unsigned		l2c_aux_mask;	/* L2 cache aux mask	*/
 	void			(*l2c_write_sec)(unsigned long, unsigned);
-	struct smp_operations	*smp;		/* SMP operations	*/
+	const struct smp_operations	*smp;	/* SMP operations	*/
 	bool			(*smp_init)(void);
 	void			(*fixup)(struct tag *, char **);
 	void			(*dt_fixup)(void);
diff --git a/arch/arm/include/asm/mach/pci.h b/arch/arm/include/asm/mach/pci.h
index 8857d2869a5f..0070e8520cd4 100644
--- a/arch/arm/include/asm/mach/pci.h
+++ b/arch/arm/include/asm/mach/pci.h
@@ -52,12 +52,6 @@ struct pci_sys_data {
 	u8		(*swizzle)(struct pci_dev *, u8 *);
 					/* IRQ mapping				*/
 	int		(*map_irq)(const struct pci_dev *, u8, u8);
-					/* Resource alignement requirements	*/
-	resource_size_t (*align_resource)(struct pci_dev *dev,
-					  const struct resource *res,
-					  resource_size_t start,
-					  resource_size_t size,
-					  resource_size_t align);
 	void		*private_data;	/* platform controller private data	*/
 };
 
diff --git a/arch/arm/include/asm/memory.h b/arch/arm/include/asm/memory.h
index 98d58bb04ac5..c79b57bf71c4 100644
--- a/arch/arm/include/asm/memory.h
+++ b/arch/arm/include/asm/memory.h
@@ -76,10 +76,12 @@
  */
 #define XIP_VIRT_ADDR(physaddr)  (MODULES_VADDR + ((physaddr) & 0x000fffff))
 
+#if !defined(CONFIG_SMP) && !defined(CONFIG_ARM_LPAE)
 /*
  * Allow 16MB-aligned ioremap pages
  */
 #define IOREMAP_MAX_ORDER	24
+#endif
 
 #else /* CONFIG_MMU */
 
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
index f40354198bad..348caabb7625 100644
--- a/arch/arm/include/asm/pgtable.h
+++ b/arch/arm/include/asm/pgtable.h
@@ -43,7 +43,7 @@
  */
 #define VMALLOC_OFFSET		(8*1024*1024)
 #define VMALLOC_START		(((unsigned long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))
-#define VMALLOC_END		0xff000000UL
+#define VMALLOC_END		0xff800000UL
 
 #define LIBRARY_TEXT_START	0x0c000000
 
diff --git a/arch/arm/include/asm/smp.h b/arch/arm/include/asm/smp.h
index ef356659b4f4..3d6dc8b460e4 100644
--- a/arch/arm/include/asm/smp.h
+++ b/arch/arm/include/asm/smp.h
@@ -112,7 +112,7 @@ struct smp_operations {
 
 struct of_cpu_method {
 	const char *method;
-	struct smp_operations *ops;
+	const struct smp_operations *ops;
 };
 
 #define CPU_METHOD_OF_DECLARE(name, _method, _ops)			\
@@ -122,6 +122,6 @@ struct of_cpu_method {
 /*
  * set platform specific SMP operations
  */
-extern void smp_set_ops(struct smp_operations *);
+extern void smp_set_ops(const struct smp_operations *);
 
 #endif /* ifndef __ASM_ARM_SMP_H */
diff --git a/arch/arm/include/asm/unistd.h b/arch/arm/include/asm/unistd.h
index 7cba573c2cc9..7b84657fba35 100644
--- a/arch/arm/include/asm/unistd.h
+++ b/arch/arm/include/asm/unistd.h
@@ -21,13 +21,6 @@
  */
 #define __NR_syscalls  (392)
 
-/*
- * *NOTE*: This is a ghost syscall private to the kernel.  Only the
- * __kuser_cmpxchg code in entry-armv.S should be aware of its
- * existence.  Don't ever use this from user code.
- */
-#define __ARM_NR_cmpxchg		(__ARM_NR_BASE+0x00fff0)
-
 #define __ARCH_WANT_STAT64
 #define __ARCH_WANT_SYS_GETHOSTNAME
 #define __ARCH_WANT_SYS_PAUSE
diff --git a/arch/arm/include/asm/xen/hypervisor.h b/arch/arm/include/asm/xen/hypervisor.h
index 04ff8e7b37df..95251512e2c4 100644
--- a/arch/arm/include/asm/xen/hypervisor.h
+++ b/arch/arm/include/asm/xen/hypervisor.h
@@ -26,4 +26,14 @@ void __init xen_early_init(void);
 static inline void xen_early_init(void) { return; }
 #endif
 
+#ifdef CONFIG_HOTPLUG_CPU
+static inline void xen_arch_register_cpu(int num)
+{
+}
+
+static inline void xen_arch_unregister_cpu(int num)
+{
+}
+#endif
+
 #endif /* _ASM_ARM_XEN_HYPERVISOR_H */
diff --git a/arch/arm/include/asm/xen/page-coherent.h b/arch/arm/include/asm/xen/page-coherent.h
index efd562412850..0375c8caa061 100644
--- a/arch/arm/include/asm/xen/page-coherent.h
+++ b/arch/arm/include/asm/xen/page-coherent.h
@@ -35,11 +35,15 @@ static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
 	     dma_addr_t dev_addr, unsigned long offset, size_t size,
 	     enum dma_data_direction dir, struct dma_attrs *attrs)
 {
-	bool local = PFN_DOWN(dev_addr) == page_to_pfn(page);
-	/* Dom0 is mapped 1:1, so if pfn == mfn the page is local otherwise
-	 * is a foreign page grant-mapped in dom0. If the page is local we
-	 * can safely call the native dma_ops function, otherwise we call
-	 * the xen specific function. */
+	bool local = XEN_PFN_DOWN(dev_addr) == page_to_xen_pfn(page);
+	/*
+	 * Dom0 is mapped 1:1, while the Linux page can be spanned accross
+	 * multiple Xen page, it's not possible to have a mix of local and
+	 * foreign Xen page. So if the first xen_pfn == mfn the page is local
+	 * otherwise it's a foreign page grant-mapped in dom0. If the page is
+	 * local we can safely call the native dma_ops function, otherwise we
+	 * call the xen specific function.
+	 */
 	if (local)
 		__generic_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
 	else
@@ -51,10 +55,14 @@ static inline void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
 		struct dma_attrs *attrs)
 {
 	unsigned long pfn = PFN_DOWN(handle);
-	/* Dom0 is mapped 1:1, so calling pfn_valid on a foreign mfn will
-	 * always return false. If the page is local we can safely call the
-	 * native dma_ops function, otherwise we call the xen specific
-	 * function. */
+	/*
+	 * Dom0 is mapped 1:1, while the Linux page can be spanned accross
+	 * multiple Xen page, it's not possible to have a mix of local and
+	 * foreign Xen page. Dom0 is mapped 1:1, so calling pfn_valid on a
+	 * foreign mfn will always return false. If the page is local we can
+	 * safely call the native dma_ops function, otherwise we call the xen
+	 * specific function.
+	 */
 	if (pfn_valid(pfn)) {
 		if (__generic_dma_ops(hwdev)->unmap_page)
 			__generic_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
diff --git a/arch/arm/include/asm/xen/page.h b/arch/arm/include/asm/xen/page.h
index 127956353b00..415dbc6e43fd 100644
--- a/arch/arm/include/asm/xen/page.h
+++ b/arch/arm/include/asm/xen/page.h
@@ -13,9 +13,6 @@
 
 #define phys_to_machine_mapping_valid(pfn) (1)
 
-#define pte_mfn	    pte_pfn
-#define mfn_pte	    pfn_pte
-
 /* Xen machine address */
 typedef struct xmaddr {
 	phys_addr_t maddr;
@@ -31,6 +28,17 @@ typedef struct xpaddr {
 
 #define INVALID_P2M_ENTRY      (~0UL)
 
+/*
+ * The pseudo-physical frame (pfn) used in all the helpers is always based
+ * on Xen page granularity (i.e 4KB).
+ *
+ * A Linux page may be split across multiple non-contiguous Xen page so we
+ * have to keep track with frame based on 4KB page granularity.
+ *
+ * PV drivers should never make a direct usage of those helpers (particularly
+ * pfn_to_gfn and gfn_to_pfn).
+ */
+
 unsigned long __pfn_to_mfn(unsigned long pfn);
 extern struct rb_root phys_to_mach;
 
@@ -67,8 +75,8 @@ static inline unsigned long bfn_to_pfn(unsigned long bfn)
 #define bfn_to_local_pfn(bfn)	bfn_to_pfn(bfn)
 
 /* VIRT <-> GUEST conversion */
-#define virt_to_gfn(v)		(pfn_to_gfn(virt_to_pfn(v)))
-#define gfn_to_virt(m)		(__va(gfn_to_pfn(m) << PAGE_SHIFT))
+#define virt_to_gfn(v)		(pfn_to_gfn(virt_to_phys(v) >> XEN_PAGE_SHIFT))
+#define gfn_to_virt(m)		(__va(gfn_to_pfn(m) << XEN_PAGE_SHIFT))
 
 /* Only used in PV code. But ARM guests are always HVM. */
 static inline xmaddr_t arbitrary_virt_to_machine(void *vaddr)
@@ -107,8 +115,8 @@ static inline bool set_phys_to_machine(unsigned long pfn, unsigned long mfn)
 #define xen_unmap(cookie) iounmap((cookie))
 
 bool xen_arch_need_swiotlb(struct device *dev,
-			   unsigned long pfn,
-			   unsigned long bfn);
+			   phys_addr_t phys,
+			   dma_addr_t dev_addr);
 unsigned long xen_get_swiotlb_free_pages(unsigned int order);
 
 #endif /* _ASM_ARM_XEN_PAGE_H */