Merge tag 'stable/for-linus-3.12-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip

Pull Xen updates from Konrad Rzeszutek Wilk:
 "A couple of features and a ton of bug-fixes.  There is also some
  maintership changes.  Jeremy is enjoying the full-time work at the
  startup and as much as he would love to help - he can't find the time.
  I have a bunch of other things that I promised to work on - paravirt
  diet, get SWIOTLB working everywhere, etc, but haven't been able to
  find the time.

  As such both David Vrabel and Boris Ostrovsky have graciously
  volunteered to help with the maintership role.  They will keep the lid
  on regressions, bug-fixes, etc.  I will be in the background to help -
  but eventually there will be less of me doing the Xen GIT pulls and
  more of them.  Stefano is still doing the ARM/ARM64 and will continue
  on doing so.

  Features:
   - Xen Trusted Platform Module (TPM) frontend driver - with the
     backend in MiniOS.
   - Scalability improvements in event channel.
   - Two extra Xen co-maintainers (David, Boris) and one going away (Jeremy)

  Bug-fixes:
   - Make the 1:1 mapping work during early bootup on selective regions.
   - Add scratch page to balloon driver to deal with unexpected code
     still holding on stale pages.
   - Allow NMIs on PV guests (64-bit only)
   - Remove unnecessary TLB flush in M2P code.
   - Fixes duplicate callbacks in Xen granttable code.
   - Fixes in PRIVCMD_MMAPBATCH ioctls to allow retries
   - Fix for events being lost due to rescheduling on different VCPUs.
   - More documentation"

* tag 'stable/for-linus-3.12-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/xen/tip: (23 commits)
  hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc
  drivers/xen-tpmfront: Fix compile issue with missing option.
  xen/balloon: don't set P2M entry for auto translated guest
  xen/evtchn: double free on error
  Xen: Fix retry calls into PRIVCMD_MMAPBATCH*.
  xen/pvhvm: Initialize xen panic handler for PVHVM guests
  xen/m2p: use GNTTABOP_unmap_and_replace to reinstate the original mapping
  xen: fix ARM build after 6efa20e4
  MAINTAINERS: Remove Jeremy from the Xen subsystem.
  xen/events: document behaviour when scanning the start word for events
  x86/xen: during early setup, only 1:1 map the ISA region
  x86/xen: disable premption when enabling local irqs
  swiotlb-xen: replace dma_length with sg_dma_len() macro
  swiotlb: replace dma_length with sg_dma_len() macro
  xen/balloon: set a mapping for ballooned out pages
  xen/evtchn: improve scalability by using per-user locks
  xen/p2m: avoid unneccesary TLB flush in m2p_remove_override()
  MAINTAINERS: Add in two extra co-maintainers of the Xen tree.
  MAINTAINERS: Update the Xen subsystem's with proper mailing list.
  xen: replace strict_strtoul() with kstrtoul()
  ...

CREDITS

@@ -1120,6 +1120,7 @@ D: author of userfs filesystem
 D: Improved mmap and munmap handling
 D: General mm minor tidyups
 D: autofs v4 maintainer
+D: Xen subsystem
 S: 987 Alabama St
 S: San Francisco
 S: CA, 94110

Documentation/tpm/xen-tpmfront.txt

+Virtual TPM interface for Xen
+
+Authors: Matthew Fioravante (JHUAPL), Daniel De Graaf (NSA)
+
+This document describes the virtual Trusted Platform Module (vTPM) subsystem for
+Xen. The reader is assumed to have familiarity with building and installing Xen,
+Linux, and a basic understanding of the TPM and vTPM concepts.
+
+INTRODUCTION
+
+The goal of this work is to provide a TPM functionality to a virtual guest
+operating system (in Xen terms, a DomU).  This allows programs to interact with
+a TPM in a virtual system the same way they interact with a TPM on the physical
+system.  Each guest gets its own unique, emulated, software TPM.  However, each
+of the vTPM's secrets (Keys, NVRAM, etc) are managed by a vTPM Manager domain,
+which seals the secrets to the Physical TPM.  If the process of creating each of
+these domains (manager, vTPM, and guest) is trusted, the vTPM subsystem extends
+the chain of trust rooted in the hardware TPM to virtual machines in Xen. Each
+major component of vTPM is implemented as a separate domain, providing secure
+separation guaranteed by the hypervisor. The vTPM domains are implemented in
+mini-os to reduce memory and processor overhead.
+
+This mini-os vTPM subsystem was built on top of the previous vTPM work done by
+IBM and Intel corporation.
+
+
+DESIGN OVERVIEW
+---------------
+
+The architecture of vTPM is described below:
+
++------------------+
+|    Linux DomU    | ...
+|       |  ^       |
+|       v  |       |
+|   xen-tpmfront   |
++------------------+
+        |  ^
+        v  |
++------------------+
+| mini-os/tpmback  |
+|       |  ^       |
+|       v  |       |
+|  vtpm-stubdom    | ...
+|       |  ^       |
+|       v  |       |
+| mini-os/tpmfront |
++------------------+
+        |  ^
+        v  |
++------------------+
+| mini-os/tpmback  |
+|       |  ^       |
+|       v  |       |
+| vtpmmgr-stubdom  |
+|       |  ^       |
+|       v  |       |
+| mini-os/tpm_tis  |
++------------------+
+        |  ^
+        v  |
++------------------+
+|   Hardware TPM   |
++------------------+
+
+ * Linux DomU: The Linux based guest that wants to use a vTPM. There may be
+	       more than one of these.
+
+ * xen-tpmfront.ko: Linux kernel virtual TPM frontend driver. This driver
+                    provides vTPM access to a Linux-based DomU.
+
+ * mini-os/tpmback: Mini-os TPM backend driver. The Linux frontend driver
+		    connects to this backend driver to facilitate communications
+		    between the Linux DomU and its vTPM. This driver is also
+		    used by vtpmmgr-stubdom to communicate with vtpm-stubdom.
+
+ * vtpm-stubdom: A mini-os stub domain that implements a vTPM. There is a
+		 one to one mapping between running vtpm-stubdom instances and
+                 logical vtpms on the system. The vTPM Platform Configuration
+                 Registers (PCRs) are normally all initialized to zero.
+
+ * mini-os/tpmfront: Mini-os TPM frontend driver. The vTPM mini-os domain
+		     vtpm-stubdom uses this driver to communicate with
+		     vtpmmgr-stubdom. This driver is also used in mini-os
+		     domains such as pv-grub that talk to the vTPM domain.
+
+ * vtpmmgr-stubdom: A mini-os domain that implements the vTPM manager. There is
+		    only one vTPM manager and it should be running during the
+		    entire lifetime of the machine.  This domain regulates
+		    access to the physical TPM on the system and secures the
+		    persistent state of each vTPM.
+
+ * mini-os/tpm_tis: Mini-os TPM version 1.2 TPM Interface Specification (TIS)
+                    driver. This driver used by vtpmmgr-stubdom to talk directly to
+                    the hardware TPM. Communication is facilitated by mapping
+                    hardware memory pages into vtpmmgr-stubdom.
+
+ * Hardware TPM: The physical TPM that is soldered onto the motherboard.
+
+
+INTEGRATION WITH XEN
+--------------------
+
+Support for the vTPM driver was added in Xen using the libxl toolstack in Xen
+4.3.  See the Xen documentation (docs/misc/vtpm.txt) for details on setting up
+the vTPM and vTPM Manager stub domains.  Once the stub domains are running, a
+vTPM device is set up in the same manner as a disk or network device in the
+domain's configuration file.
+
+In order to use features such as IMA that require a TPM to be loaded prior to
+the initrd, the xen-tpmfront driver must be compiled in to the kernel.  If not
+using such features, the driver can be compiled as a module and will be loaded
+as usual.

MAINTAINERS

@@ -9278,9 +9278,9 @@ F:	drivers/media/tuners/tuner-xc2028.*
 
 XEN HYPERVISOR INTERFACE
 M:	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-M:	Jeremy Fitzhardinge <jeremy@goop.org>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
-L:	virtualization@lists.linux-foundation.org
+M:	Boris Ostrovsky <boris.ostrovsky@oracle.com>
+M:	David Vrabel <david.vrabel@citrix.com>
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 S:	Supported
 F:	arch/x86/xen/
 F:	drivers/*/xen-*front.c
@@ -9291,35 +9291,35 @@ F:	include/uapi/xen/
 
 XEN HYPERVISOR ARM
 M:	Stefano Stabellini <stefano.stabellini@eu.citrix.com>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 S:	Supported
 F:	arch/arm/xen/
 F:	arch/arm/include/asm/xen/
 
 XEN HYPERVISOR ARM64
 M:	Stefano Stabellini <stefano.stabellini@eu.citrix.com>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 S:	Supported
 F:	arch/arm64/xen/
 F:	arch/arm64/include/asm/xen/
 
 XEN NETWORK BACKEND DRIVER
 M:	Ian Campbell <ian.campbell@citrix.com>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 L:	netdev@vger.kernel.org
 S:	Supported
 F:	drivers/net/xen-netback/*
 
 XEN PCI SUBSYSTEM
 M:	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 S:	Supported
 F:	arch/x86/pci/*xen*
 F:	drivers/pci/*xen*
 
 XEN SWIOTLB SUBSYSTEM
 M:	Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
-L:	xen-devel@lists.xensource.com (moderated for non-subscribers)
+L:	xen-devel@lists.xenproject.org (moderated for non-subscribers)
 S:	Supported
 F:	arch/x86/xen/*swiotlb*
 F:	drivers/xen/*swiotlb*

arch/x86/include/asm/xen/events.h

@@ -7,6 +7,7 @@ enum ipi_vector {
 	XEN_CALL_FUNCTION_SINGLE_VECTOR,
 	XEN_SPIN_UNLOCK_VECTOR,
 	XEN_IRQ_WORK_VECTOR,
+	XEN_NMI_VECTOR,
 
 	XEN_NR_IPIS,
 };

arch/x86/xen/enlighten.c

@@ -427,8 +427,7 @@ static void __init xen_init_cpuid_mask(void)
 
 	if (!xen_initial_domain())
 		cpuid_leaf1_edx_mask &=
-			~((1 << X86_FEATURE_APIC) |  /* disable local APIC */
-			  (1 << X86_FEATURE_ACPI));  /* disable ACPI */
+			~((1 << X86_FEATURE_ACPI));  /* disable ACPI */
 
 	cpuid_leaf1_ecx_mask &= ~(1 << (X86_FEATURE_X2APIC % 32));
 
@@ -735,8 +734,7 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val,
 		addr = (unsigned long)xen_int3;
 	else if (addr == (unsigned long)stack_segment)
 		addr = (unsigned long)xen_stack_segment;
-	else if (addr == (unsigned long)double_fault ||
-		 addr == (unsigned long)nmi) {
+	else if (addr == (unsigned long)double_fault) {
 		/* Don't need to handle these */
 		return 0;
 #ifdef CONFIG_X86_MCE
@@ -747,7 +745,12 @@ static int cvt_gate_to_trap(int vector, const gate_desc *val,
 		 */
 		;
 #endif
-	} else {
+	} else if (addr == (unsigned long)nmi)
+		/*
+		 * Use the native version as well.
+		 */
+		;
+	else {
 		/* Some other trap using IST? */
 		if (WARN_ON(val->ist != 0))
 			return 0;
@@ -1710,6 +1713,8 @@ static void __init xen_hvm_guest_init(void)
 
 	xen_hvm_init_shared_info();
 
+	xen_panic_handler_init();
+
 	if (xen_feature(XENFEAT_hvm_callback_vector))
 		xen_have_vector_callback = 1;
 	xen_hvm_smp_init();

arch/x86/xen/irq.c

@@ -47,23 +47,18 @@ static void xen_restore_fl(unsigned long flags)
 	/* convert from IF type flag */
 	flags = !(flags & X86_EFLAGS_IF);
 
-	/* There's a one instruction preempt window here.  We need to
-	   make sure we're don't switch CPUs between getting the vcpu
-	   pointer and updating the mask. */
+	/* See xen_irq_enable() for why preemption must be disabled. */
 	preempt_disable();
 	vcpu = this_cpu_read(xen_vcpu);
 	vcpu->evtchn_upcall_mask = flags;
-	preempt_enable_no_resched();
-
-	/* Doesn't matter if we get preempted here, because any
-	   pending event will get dealt with anyway. */
 
 	if (flags == 0) {
-		preempt_check_resched();
 		barrier(); /* unmask then check (avoid races) */
 		if (unlikely(vcpu->evtchn_upcall_pending))
 			xen_force_evtchn_callback();
-	}
+		preempt_enable();
+	} else
+		preempt_enable_no_resched();
 }
 PV_CALLEE_SAVE_REGS_THUNK(xen_restore_fl);
 
@@ -82,10 +77,12 @@ static void xen_irq_enable(void)
 {
 	struct vcpu_info *vcpu;
 
-	/* We don't need to worry about being preempted here, since
-	   either a) interrupts are disabled, so no preemption, or b)
-	   the caller is confused and is trying to re-enable interrupts
-	   on an indeterminate processor. */
+	/*
+	 * We may be preempted as soon as vcpu->evtchn_upcall_mask is
+	 * cleared, so disable preemption to ensure we check for
+	 * events on the VCPU we are still running on.
+	 */
+	preempt_disable();
 
 	vcpu = this_cpu_read(xen_vcpu);
 	vcpu->evtchn_upcall_mask = 0;
@@ -96,6 +93,8 @@ static void xen_irq_enable(void)
 	barrier(); /* unmask then check (avoid races) */
 	if (unlikely(vcpu->evtchn_upcall_pending))
 		xen_force_evtchn_callback();
+
+	preempt_enable();
 }
 PV_CALLEE_SAVE_REGS_THUNK(xen_irq_enable);
 

arch/x86/xen/p2m.c

@@ -161,6 +161,7 @@
 #include <asm/xen/page.h>
 #include <asm/xen/hypercall.h>
 #include <asm/xen/hypervisor.h>
+#include <xen/balloon.h>
 #include <xen/grant_table.h>
 
 #include "multicalls.h"
@@ -967,7 +968,10 @@ int m2p_remove_override(struct page *page,
 	if (kmap_op != NULL) {
 		if (!PageHighMem(page)) {
 			struct multicall_space mcs;
-			struct gnttab_unmap_grant_ref *unmap_op;
+			struct gnttab_unmap_and_replace *unmap_op;
+			struct page *scratch_page = get_balloon_scratch_page();
+			unsigned long scratch_page_address = (unsigned long)
+				__va(page_to_pfn(scratch_page) << PAGE_SHIFT);
 
 			/*
 			 * It might be that we queued all the m2p grant table
@@ -990,21 +994,25 @@ int m2p_remove_override(struct page *page,
 			}
 
 			mcs = xen_mc_entry(
-					sizeof(struct gnttab_unmap_grant_ref));
+					sizeof(struct gnttab_unmap_and_replace));
 			unmap_op = mcs.args;
 			unmap_op->host_addr = kmap_op->host_addr;
+			unmap_op->new_addr = scratch_page_address;
 			unmap_op->handle = kmap_op->handle;
-			unmap_op->dev_bus_addr = 0;
 
 			MULTI_grant_table_op(mcs.mc,
-					GNTTABOP_unmap_grant_ref, unmap_op, 1);
+					GNTTABOP_unmap_and_replace, unmap_op, 1);
 
 			xen_mc_issue(PARAVIRT_LAZY_MMU);
 
-			set_pte_at(&init_mm, address, ptep,
-					pfn_pte(pfn, PAGE_KERNEL));
-			__flush_tlb_single(address);
+			mcs = __xen_mc_entry(0);
+			MULTI_update_va_mapping(mcs.mc, scratch_page_address,
+					pfn_pte(page_to_pfn(get_balloon_scratch_page()),
+					PAGE_KERNEL_RO), 0);
+			xen_mc_issue(PARAVIRT_LAZY_MMU);
+
 			kmap_op->host_addr = 0;
+			put_balloon_scratch_page();
 		}
 	}
 

arch/x86/xen/setup.c

@@ -33,6 +33,9 @@
 /* These are code, but not functions.  Defined in entry.S */
 extern const char xen_hypervisor_callback[];
 extern const char xen_failsafe_callback[];
+#ifdef CONFIG_X86_64
+extern const char nmi[];
+#endif
 extern void xen_sysenter_target(void);
 extern void xen_syscall_target(void);
 extern void xen_syscall32_target(void);
@@ -215,13 +218,19 @@ static void __init xen_set_identity_and_release_chunk(
 	unsigned long pfn;
 
 	/*
-	 * If the PFNs are currently mapped, the VA mapping also needs
-	 * to be updated to be 1:1.
+	 * If the PFNs are currently mapped, clear the mappings
+	 * (except for the ISA region which must be 1:1 mapped) to
+	 * release the refcounts (in Xen) on the original frames.
 	 */
-	for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++)
+	for (pfn = start_pfn; pfn <= max_pfn_mapped && pfn < end_pfn; pfn++) {
+		pte_t pte = __pte_ma(0);
+
+		if (pfn < PFN_UP(ISA_END_ADDRESS))
+			pte = mfn_pte(pfn, PAGE_KERNEL_IO);
+
 		(void)HYPERVISOR_update_va_mapping(
-			(unsigned long)__va(pfn << PAGE_SHIFT),
-			mfn_pte(pfn, PAGE_KERNEL_IO), 0);
+			(unsigned long)__va(pfn << PAGE_SHIFT), pte, 0);
+	}
 
 	if (start_pfn < nr_pages)
 		*released += xen_release_chunk(
@@ -547,7 +556,13 @@ void xen_enable_syscall(void)
 	}
 #endif /* CONFIG_X86_64 */
 }
-
+void __cpuinit xen_enable_nmi(void)
+{
+#ifdef CONFIG_X86_64
+	if (register_callback(CALLBACKTYPE_nmi, nmi))
+		BUG();
+#endif
+}
 void __init xen_arch_setup(void)
 {
 	xen_panic_handler_init();
@@ -565,7 +580,7 @@ void __init xen_arch_setup(void)
 
 	xen_enable_sysenter();
 	xen_enable_syscall();
-
+	xen_enable_nmi();
 #ifdef CONFIG_ACPI
 	if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
 		printk(KERN_INFO "ACPI in unprivileged domain disabled\n");

arch/x86/xen/smp.c

@@ -573,6 +573,12 @@ static inline int xen_map_vector(int vector)
 	case IRQ_WORK_VECTOR:
 		xen_vector = XEN_IRQ_WORK_VECTOR;
 		break;
+#ifdef CONFIG_X86_64
+	case NMI_VECTOR:
+	case APIC_DM_NMI: /* Some use that instead of NMI_VECTOR */
+		xen_vector = XEN_NMI_VECTOR;
+		break;
+#endif
 	default:
 		xen_vector = -1;
 		printk(KERN_ERR "xen: vector 0x%x is not implemented\n",

drivers/char/tpm/Kconfig

@@ -91,4 +91,16 @@ config TCG_ST33_I2C
         To compile this driver as a module, choose M here; the module will be
         called tpm_stm_st33_i2c.
 
+config TCG_XEN
+	tristate "XEN TPM Interface"
+	depends on TCG_TPM && XEN
+	select XEN_XENBUS_FRONTEND
+	---help---
+	  If you want to make TPM support available to a Xen user domain,
+	  say Yes and it will be accessible from within Linux. See
+	  the manpages for xl, xl.conf, and docs/misc/vtpm.txt in
+	  the Xen source repository for more details.
+	  To compile this driver as a module, choose M here; the module
+	  will be called xen-tpmfront.
+
 endif # TCG_TPM

drivers/char/tpm/Makefile

@@ -18,3 +18,4 @@ obj-$(CONFIG_TCG_ATMEL) += tpm_atmel.o
 obj-$(CONFIG_TCG_INFINEON) += tpm_infineon.o
 obj-$(CONFIG_TCG_IBMVTPM) += tpm_ibmvtpm.o
 obj-$(CONFIG_TCG_ST33_I2C) += tpm_i2c_stm_st33.o
+obj-$(CONFIG_TCG_XEN) += xen-tpmfront.o

drivers/xen/balloon.c

@@ -38,6 +38,7 @@
 
 #define pr_fmt(fmt) "xen:" KBUILD_MODNAME ": " fmt
 
+#include <linux/cpu.h>
 #include <linux/kernel.h>
 #include <linux/sched.h>
 #include <linux/errno.h>
@@ -52,6 +53,7 @@
 #include <linux/notifier.h>
 #include <linux/memory.h>
 #include <linux/memory_hotplug.h>
+#include <linux/percpu-defs.h>
 
 #include <asm/page.h>
 #include <asm/pgalloc.h>
@@ -90,6 +92,8 @@ EXPORT_SYMBOL_GPL(balloon_stats);
 
 /* We increase/decrease in batches which fit in a page */
 static xen_pfn_t frame_list[PAGE_SIZE / sizeof(unsigned long)];
+static DEFINE_PER_CPU(struct page *, balloon_scratch_page);
+
 
 /* List of ballooned pages, threaded through the mem_map array. */
 static LIST_HEAD(ballooned_pages);
@@ -412,7 +416,8 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 		if (xen_pv_domain() && !PageHighMem(page)) {
 			ret = HYPERVISOR_update_va_mapping(
 				(unsigned long)__va(pfn << PAGE_SHIFT),
-				__pte_ma(0), 0);
+				pfn_pte(page_to_pfn(__get_cpu_var(balloon_scratch_page)),
+					PAGE_KERNEL_RO), 0);
 			BUG_ON(ret);
 		}
 #endif
@@ -425,7 +430,13 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp)
 	/* No more mappings: invalidate P2M and add to balloon. */
 	for (i = 0; i < nr_pages; i++) {
 		pfn = mfn_to_pfn(frame_list[i]);
-		__set_phys_to_machine(pfn, INVALID_P2M_ENTRY);
+		if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+			unsigned long p;
+			struct page *pg;
+			pg = __get_cpu_var(balloon_scratch_page);
+			p = page_to_pfn(pg);
+			__set_phys_to_machine(pfn, pfn_to_mfn(p));
+		}
 		balloon_append(pfn_to_page(pfn));
 	}
 
@@ -480,6 +491,18 @@ static void balloon_process(struct work_struct *work)
 	mutex_unlock(&balloon_mutex);
 }
 
+struct page *get_balloon_scratch_page(void)
+{
+	struct page *ret = get_cpu_var(balloon_scratch_page);
+	BUG_ON(ret == NULL);
+	return ret;
+}
+
+void put_balloon_scratch_page(void)
+{
+	put_cpu_var(balloon_scratch_page);
+}
+
 /* Resets the Xen limit, sets new target, and kicks off processing. */
 void balloon_set_new_target(unsigned long target)
 {
@@ -573,13 +596,47 @@ static void __init balloon_add_region(unsigned long start_pfn,
 	}
 }
 
+static int __cpuinit balloon_cpu_notify(struct notifier_block *self,
+				    unsigned long action, void *hcpu)
+{
+	int cpu = (long)hcpu;
+	switch (action) {
+	case CPU_UP_PREPARE:
+		if (per_cpu(balloon_scratch_page, cpu) != NULL)
+			break;
+		per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL);
+		if (per_cpu(balloon_scratch_page, cpu) == NULL) {
+			pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu);
+			return NOTIFY_BAD;
+		}
+		break;
+	default:
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block balloon_cpu_notifier __cpuinitdata = {
+	.notifier_call	= balloon_cpu_notify,
+};
+
 static int __init balloon_init(void)
 {
-	int i;
+	int i, cpu;
 
 	if (!xen_domain())
 		return -ENODEV;
 
+	for_each_online_cpu(cpu)
+	{
+		per_cpu(balloon_scratch_page, cpu) = alloc_page(GFP_KERNEL);
+		if (per_cpu(balloon_scratch_page, cpu) == NULL) {
+			pr_warn("Failed to allocate balloon_scratch_page for cpu %d\n", cpu);
+			return -ENOMEM;
+		}
+	}
+	register_cpu_notifier(&balloon_cpu_notifier);
+
 	pr_info("Initialising balloon driver\n");
 
 	balloon_stats.current_pages = xen_pv_domain()
@@ -616,4 +673,15 @@ static int __init balloon_init(void)
 
 subsys_initcall(balloon_init);
 
+static int __init balloon_clear(void)
+{
+	int cpu;
+
+	for_each_possible_cpu(cpu)
+		per_cpu(balloon_scratch_page, cpu) = NULL;
+
+	return 0;
+}
+early_initcall(balloon_clear);
+
 MODULE_LICENSE("GPL");

drivers/xen/events.c

@@ -56,6 +56,7 @@
 #include <xen/interface/hvm/params.h>
 #include <xen/interface/physdev.h>
 #include <xen/interface/sched.h>
+#include <xen/interface/vcpu.h>
 #include <asm/hw_irq.h>
 
 /*
@@ -1212,7 +1213,17 @@ EXPORT_SYMBOL_GPL(evtchn_put);
 
 void xen_send_IPI_one(unsigned int cpu, enum ipi_vector vector)
 {
-	int irq = per_cpu(ipi_to_irq, cpu)[vector];
+	int irq;
+
+#ifdef CONFIG_X86
+	if (unlikely(vector == XEN_NMI_VECTOR)) {
+		int rc =  HYPERVISOR_vcpu_op(VCPUOP_send_nmi, cpu, NULL);
+		if (rc < 0)
+			printk(KERN_WARNING "Sending nmi to CPU%d failed (rc:%d)\n", cpu, rc);
+		return;
+	}
+#endif
+	irq = per_cpu(ipi_to_irq, cpu)[vector];
 	BUG_ON(irq < 0);
 	notify_remote_via_irq(irq);
 }
@@ -1379,14 +1390,21 @@ static void __xen_evtchn_do_upcall(void)
 
 			pending_bits = active_evtchns(cpu, s, word_idx);
 			bit_idx = 0; /* usually scan entire word from start */
+			/*
+			 * We scan the starting word in two parts.
+			 *
+			 * 1st time: start in the middle, scanning the
+			 * upper bits.
+			 *
+			 * 2nd time: scan the whole word (not just the
+			 * parts skipped in the first pass) -- if an
+			 * event in the previously scanned bits is
+			 * pending again it would just be scanned on
+			 * the next loop anyway.
+			 */
 			if (word_idx == start_word_idx) {
-				/* We scan the starting word in two parts */
 				if (i == 0)
-					/* 1st time: start in the middle */
 					bit_idx = start_bit_idx;
-				else
-					/* 2nd time: mask bits done already */
-					bit_idx &= (1UL << start_bit_idx) - 1;
 			}
 
 			do {

drivers/xen/evtchn.c

@@ -57,6 +57,7 @@
 
 struct per_user_data {
 	struct mutex bind_mutex; /* serialize bind/unbind operations */
+	struct rb_root evtchns;
 
 	/* Notification ring, accessed via /dev/xen/evtchn. */
 #define EVTCHN_RING_SIZE     (PAGE_SIZE / sizeof(evtchn_port_t))
@@ -64,6 +65,7 @@ struct per_user_data {
 	evtchn_port_t *ring;
 	unsigned int ring_cons, ring_prod, ring_overflow;
 	struct mutex ring_cons_mutex; /* protect against concurrent readers */
+	spinlock_t ring_prod_lock; /* product against concurrent interrupts */
 
 	/* Processes wait on this queue when ring is empty. */
 	wait_queue_head_t evtchn_wait;
@@ -71,54 +73,79 @@ struct per_user_data {
 	const char *name;
 };
 
-/*
- * Who's bound to each port?  This is logically an array of struct
- * per_user_data *, but we encode the current enabled-state in bit 0.
- */
-static unsigned long *port_user;
-static DEFINE_SPINLOCK(port_user_lock); /* protects port_user[] and ring_prod */
+struct user_evtchn {
+	struct rb_node node;
+	struct per_user_data *user;
+	unsigned port;
+	bool enabled;
+};
 
-static inline struct per_user_data *get_port_user(unsigned port)
+static int add_evtchn(struct per_user_data *u, struct user_evtchn *evtchn)
 {
-	return (struct per_user_data *)(port_user[port] & ~1);
-}
+	struct rb_node **new = &(u->evtchns.rb_node), *parent = NULL;
 
-static inline void set_port_user(unsigned port, struct per_user_data *u)
-{
-	port_user[port] = (unsigned long)u;
+	while (*new) {
+		struct user_evtchn *this;
+
+		this = container_of(*new, struct user_evtchn, node);
+
+		parent = *new;
+		if (this->port < evtchn->port)
+			new = &((*new)->rb_left);
+		else if (this->port > evtchn->port)
+			new = &((*new)->rb_right);
+		else
+			return -EEXIST;
+	}
+
+	/* Add new node and rebalance tree. */
+	rb_link_node(&evtchn->node, parent, new);
+	rb_insert_color(&evtchn->node, &u->evtchns);
+
+	return 0;
 }
 
-static inline bool get_port_enabled(unsigned port)
+static void del_evtchn(struct per_user_data *u, struct user_evtchn *evtchn)
 {
-	return port_user[port] & 1;
+	rb_erase(&evtchn->node, &u->evtchns);
+	kfree(evtchn);
 }
 
-static inline void set_port_enabled(unsigned port, bool enabled)
+static struct user_evtchn *find_evtchn(struct per_user_data *u, unsigned port)
 {
-	if (enabled)
-		port_user[port] |= 1;
+	struct rb_node *node = u->evtchns.rb_node;
+
+	while (node) {
+		struct user_evtchn *evtchn;
+
+		evtchn = container_of(node, struct user_evtchn, node);
+
+		if (evtchn->port < port)
+			node = node->rb_left;
+		else if (evtchn->port > port)
+			node = node->rb_right;
 		else
-		port_user[port] &= ~1;
+			return evtchn;
+	}
+	return NULL;
 }
 
 static irqreturn_t evtchn_interrupt(int irq, void *data)
 {
-	unsigned int port = (unsigned long)data;
-	struct per_user_data *u;
-
-	spin_lock(&port_user_lock);
-
-	u = get_port_user(port);
+	struct user_evtchn *evtchn = data;
+	struct per_user_data *u = evtchn->user;
 
-	WARN(!get_port_enabled(port),
+	WARN(!evtchn->enabled,
 	     "Interrupt for port %d, but apparently not enabled; per-user %p\n",
-	     port, u);
+	     evtchn->port, u);
 
 	disable_irq_nosync(irq);
-	set_port_enabled(port, false);
+	evtchn->enabled = false;
+
+	spin_lock(&u->ring_prod_lock);
 
 	if ((u->ring_prod - u->ring_cons) < EVTCHN_RING_SIZE) {
-		u->ring[EVTCHN_RING_MASK(u->ring_prod)] = port;
+		u->ring[EVTCHN_RING_MASK(u->ring_prod)] = evtchn->port;
 		wmb(); /* Ensure ring contents visible */
 		if (u->ring_cons == u->ring_prod++) {
 			wake_up_interruptible(&u->evtchn_wait);
@@ -128,7 +155,7 @@ static irqreturn_t evtchn_interrupt(int irq, void *data)
 	} else
 		u->ring_overflow = 1;
 
-	spin_unlock(&port_user_lock);
+	spin_unlock(&u->ring_prod_lock);
 
 	return IRQ_HANDLED;
 }
@@ -229,20 +256,20 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf,
 	if (copy_from_user(kbuf, buf, count) != 0)
 		goto out;
 
-	spin_lock_irq(&port_user_lock);
+	mutex_lock(&u->bind_mutex);
 
 	for (i = 0; i < (count/sizeof(evtchn_port_t)); i++) {
 		unsigned port = kbuf[i];
+		struct user_evtchn *evtchn;
 
-		if (port < NR_EVENT_CHANNELS &&
-		    get_port_user(port) == u &&
-		    !get_port_enabled(port)) {
-			set_port_enabled(port, true);
+		evtchn = find_evtchn(u, port);
+		if (evtchn && !evtchn->enabled) {
+			evtchn->enabled = true;
 			enable_irq(irq_from_evtchn(port));
 		}
 	}
 
-	spin_unlock_irq(&port_user_lock);
+	mutex_unlock(&u->bind_mutex);
 
 	rc = count;
 
@@ -253,6 +280,8 @@ static ssize_t evtchn_write(struct file *file, const char __user *buf,
 
 static int evtchn_bind_to_user(struct per_user_data *u, int port)
 {
+	struct user_evtchn *evtchn;
+	struct evtchn_close close;
 	int rc = 0;
 
 	/*
@@ -263,35 +292,46 @@ static int evtchn_bind_to_user(struct per_user_data *u, int port)
 	 * interrupt handler yet, and our caller has already
 	 * serialized bind operations.)
 	 */
-	BUG_ON(get_port_user(port) != NULL);
-	set_port_user(port, u);
-	set_port_enabled(port, true); /* start enabled */
+
+	evtchn = kzalloc(sizeof(*evtchn), GFP_KERNEL);
+	if (!evtchn)
+		return -ENOMEM;
+
+	evtchn->user = u;
+	evtchn->port = port;
+	evtchn->enabled = true; /* start enabled */
+
+	rc = add_evtchn(u, evtchn);
+	if (rc < 0)
+		goto err;
 
 	rc = bind_evtchn_to_irqhandler(port, evtchn_interrupt, IRQF_DISABLED,
-				       u->name, (void *)(unsigned long)port);
-	if (rc >= 0)
+				       u->name, evtchn);
+	if (rc < 0)
+		goto err;
+
 	rc = evtchn_make_refcounted(port);
-	else {
+	return rc;
+
+err:
 	/* bind failed, should close the port now */
-		struct evtchn_close close;
 	close.port = port;
 	if (HYPERVISOR_event_channel_op(EVTCHNOP_close, &close) != 0)
 		BUG();
-		set_port_user(port, NULL);
-	}
-
+	del_evtchn(u, evtchn);
 	return rc;
 }
 
-static void evtchn_unbind_from_user(struct per_user_data *u, int port)
+static void evtchn_unbind_from_user(struct per_user_data *u,
+				    struct user_evtchn *evtchn)
 {
-	int irq = irq_from_evtchn(port);
+	int irq = irq_from_evtchn(evtchn->port);
 
 	BUG_ON(irq < 0);
 
-	unbind_from_irqhandler(irq, (void *)(unsigned long)port);
+	unbind_from_irqhandler(irq, evtchn);
 
-	set_port_user(port, NULL);
+	del_evtchn(u, evtchn);
 }
 
 static long evtchn_ioctl(struct file *file,
@@ -370,6 +410,7 @@ static long evtchn_ioctl(struct file *file,
 
 	case IOCTL_EVTCHN_UNBIND: {
 		struct ioctl_evtchn_unbind unbind;
+		struct user_evtchn *evtchn;
 
 		rc = -EFAULT;
 		if (copy_from_user(&unbind, uarg, sizeof(unbind)))
@@ -380,29 +421,27 @@ static long evtchn_ioctl(struct file *file,
 			break;
 
 		rc = -ENOTCONN;
-		if (get_port_user(unbind.port) != u)
+		evtchn = find_evtchn(u, unbind.port);
+		if (!evtchn)
 			break;
 
 		disable_irq(irq_from_evtchn(unbind.port));
-
-		evtchn_unbind_from_user(u, unbind.port);
-
+		evtchn_unbind_from_user(u, evtchn);
 		rc = 0;
 		break;
 	}
 
 	case IOCTL_EVTCHN_NOTIFY: {
 		struct ioctl_evtchn_notify notify;
+		struct user_evtchn *evtchn;
 
 		rc = -EFAULT;
 		if (copy_from_user(&notify, uarg, sizeof(notify)))
 			break;
 
-		if (notify.port >= NR_EVENT_CHANNELS) {
-			rc = -EINVAL;
-		} else if (get_port_user(notify.port) != u) {
 		rc = -ENOTCONN;
-		} else {
+		evtchn = find_evtchn(u, notify.port);
+		if (evtchn) {
 			notify_remote_via_evtchn(notify.port);
 			rc = 0;
 		}
@@ -412,9 +451,9 @@ static long evtchn_ioctl(struct file *file,
 	case IOCTL_EVTCHN_RESET: {
 		/* Initialise the ring to empty. Clear errors. */
 		mutex_lock(&u->ring_cons_mutex);
-		spin_lock_irq(&port_user_lock);
+		spin_lock_irq(&u->ring_prod_lock);
 		u->ring_cons = u->ring_prod = u->ring_overflow = 0;
-		spin_unlock_irq(&port_user_lock);
+		spin_unlock_irq(&u->ring_prod_lock);
 		mutex_unlock(&u->ring_cons_mutex);
 		rc = 0;
 		break;
@@ -473,6 +512,7 @@ static int evtchn_open(struct inode *inode, struct file *filp)
 
 	mutex_init(&u->bind_mutex);
 	mutex_init(&u->ring_cons_mutex);
+	spin_lock_init(&u->ring_prod_lock);
 
 	filp->private_data = u;
 
@@ -481,15 +521,15 @@ static int evtchn_open(struct inode *inode, struct file *filp)
 
 static int evtchn_release(struct inode *inode, struct file *filp)
 {
-	int i;
 	struct per_user_data *u = filp->private_data;
+	struct rb_node *node;
 
-	for (i = 0; i < NR_EVENT_CHANNELS; i++) {
-		if (get_port_user(i) != u)
-			continue;
+	while ((node = u->evtchns.rb_node)) {
+		struct user_evtchn *evtchn;
 
-		disable_irq(irq_from_evtchn(i));
-		evtchn_unbind_from_user(get_port_user(i), i);
+		evtchn = rb_entry(node, struct user_evtchn, node);
+		disable_irq(irq_from_evtchn(evtchn->port));
+		evtchn_unbind_from_user(u, evtchn);
 	}
 
 	free_page((unsigned long)u->ring);
@@ -523,12 +563,6 @@ static int __init evtchn_init(void)
 	if (!xen_domain())
 		return -ENODEV;
 
-	port_user = kcalloc(NR_EVENT_CHANNELS, sizeof(*port_user), GFP_KERNEL);
-	if (port_user == NULL)
-		return -ENOMEM;
-
-	spin_lock_init(&port_user_lock);
-
 	/* Create '/dev/xen/evtchn'. */
 	err = misc_register(&evtchn_miscdev);
 	if (err != 0) {
@@ -543,9 +577,6 @@ static int __init evtchn_init(void)
 
 static void __exit evtchn_cleanup(void)
 {
-	kfree(port_user);
-	port_user = NULL;
-
 	misc_deregister(&evtchn_miscdev);
 }
 

drivers/xen/gntdev.c

@@ -272,19 +272,12 @@ static int map_grant_pages(struct grant_map *map)
 		 * with find_grant_ptes.
 		 */
 		for (i = 0; i < map->count; i++) {
-			unsigned level;
 			unsigned long address = (unsigned long)
 				pfn_to_kaddr(page_to_pfn(map->pages[i]));
-			pte_t *ptep;
-			u64 pte_maddr = 0;
 			BUG_ON(PageHighMem(map->pages[i]));
 
-			ptep = lookup_address(address, &level);
-			pte_maddr = arbitrary_virt_to_machine(ptep).maddr;
-			gnttab_set_map_op(&map->kmap_ops[i], pte_maddr,
-				map->flags |
-				GNTMAP_host_map |
-				GNTMAP_contains_pte,
+			gnttab_set_map_op(&map->kmap_ops[i], address,
+				map->flags | GNTMAP_host_map,
 				map->grants[i].ref,
 				map->grants[i].domid);
 		}

drivers/xen/grant-table.c

@@ -730,9 +730,18 @@ void gnttab_request_free_callback(struct gnttab_free_callback *callback,
 				  void (*fn)(void *), void *arg, u16 count)
 {
 	unsigned long flags;
+	struct gnttab_free_callback *cb;
+
 	spin_lock_irqsave(&gnttab_list_lock, flags);
-	if (callback->next)
+
+	/* Check if the callback is already on the list */
+	cb = gnttab_free_callback_list;
+	while (cb) {
+		if (cb == callback)
 			goto out;
+		cb = cb->next;
+	}
+
 	callback->fn = fn;
 	callback->arg = arg;
 	callback->count = count;

drivers/xen/privcmd.c

@@ -43,9 +43,10 @@ MODULE_LICENSE("GPL");
 
 #define PRIV_VMA_LOCKED ((void *)1)
 
-#ifndef HAVE_ARCH_PRIVCMD_MMAP
-static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma);
-#endif
+static int privcmd_vma_range_is_mapped(
+               struct vm_area_struct *vma,
+               unsigned long addr,
+               unsigned long nr_pages);
 
 static long privcmd_ioctl_hypercall(void __user *udata)
 {
@@ -225,9 +226,9 @@ static long privcmd_ioctl_mmap(void __user *udata)
 		vma = find_vma(mm, msg->va);
 		rc = -EINVAL;
 
-		if (!vma || (msg->va != vma->vm_start) ||
-		    !privcmd_enforce_singleshot_mapping(vma))
+		if (!vma || (msg->va != vma->vm_start) || vma->vm_private_data)
 			goto out_up;
+		vma->vm_private_data = PRIV_VMA_LOCKED;
 	}
 
 	state.va = vma->vm_start;
@@ -358,7 +359,7 @@ static int alloc_empty_pages(struct vm_area_struct *vma, int numpgs)
 		kfree(pages);
 		return -ENOMEM;
 	}
-	BUG_ON(vma->vm_private_data != PRIV_VMA_LOCKED);
+	BUG_ON(vma->vm_private_data != NULL);
 	vma->vm_private_data = pages;
 
 	return 0;
@@ -421,19 +422,43 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 
 	vma = find_vma(mm, m.addr);
 	if (!vma ||
-	    vma->vm_ops != &privcmd_vm_ops ||
-	    (m.addr != vma->vm_start) ||
-	    ((m.addr + (nr_pages << PAGE_SHIFT)) != vma->vm_end) ||
-	    !privcmd_enforce_singleshot_mapping(vma)) {
-		up_write(&mm->mmap_sem);
+	    vma->vm_ops != &privcmd_vm_ops) {
 		ret = -EINVAL;
-		goto out;
+		goto out_unlock;
+	}
+
+	/*
+	 * Caller must either:
+	 *
+	 * Map the whole VMA range, which will also allocate all the
+	 * pages required for the auto_translated_physmap case.
+	 *
+	 * Or
+	 *
+	 * Map unmapped holes left from a previous map attempt (e.g.,
+	 * because those foreign frames were previously paged out).
+	 */
+	if (vma->vm_private_data == NULL) {
+		if (m.addr != vma->vm_start ||
+		    m.addr + (nr_pages << PAGE_SHIFT) != vma->vm_end) {
+			ret = -EINVAL;
+			goto out_unlock;
 		}
 		if (xen_feature(XENFEAT_auto_translated_physmap)) {
 			ret = alloc_empty_pages(vma, m.num);
-		if (ret < 0) {
-			up_write(&mm->mmap_sem);
-			goto out;
+			if (ret < 0)
+				goto out_unlock;
+		} else
+			vma->vm_private_data = PRIV_VMA_LOCKED;
+	} else {
+		if (m.addr < vma->vm_start ||
+		    m.addr + (nr_pages << PAGE_SHIFT) > vma->vm_end) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (privcmd_vma_range_is_mapped(vma, m.addr, nr_pages)) {
+			ret = -EINVAL;
+			goto out_unlock;
 		}
 	}
 
@@ -466,8 +491,11 @@ static long privcmd_ioctl_mmap_batch(void __user *udata, int version)
 
 out:
 	free_page_list(&pagelist);
-
 	return ret;
+
+out_unlock:
+	up_write(&mm->mmap_sem);
+	goto out;
 }
 
 static long privcmd_ioctl(struct file *file,
@@ -540,9 +568,24 @@ static int privcmd_mmap(struct file *file, struct vm_area_struct *vma)
 	return 0;
 }
 
-static int privcmd_enforce_singleshot_mapping(struct vm_area_struct *vma)
+/*
+ * For MMAPBATCH*. This allows asserting the singleshot mapping
+ * on a per pfn/pte basis. Mapping calls that fail with ENOENT
+ * can be then retried until success.
+ */
+static int is_mapped_fn(pte_t *pte, struct page *pmd_page,
+	                unsigned long addr, void *data)
+{
+	return pte_none(*pte) ? 0 : -EBUSY;
+}
+
+static int privcmd_vma_range_is_mapped(
+	           struct vm_area_struct *vma,
+	           unsigned long addr,
+	           unsigned long nr_pages)
 {
-	return !cmpxchg(&vma->vm_private_data, NULL, PRIV_VMA_LOCKED);
+	return apply_to_page_range(vma->vm_mm, addr, nr_pages << PAGE_SHIFT,
+				   is_mapped_fn, NULL) != 0;
 }
 
 const struct file_operations xen_privcmd_fops = {

drivers/xen/swiotlb-xen.c

@@ -506,13 +506,13 @@ xen_swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
 				   to do proper error handling. */
 				xen_swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
 							   attrs);
-				sgl[0].dma_length = 0;
+				sg_dma_len(sgl) = 0;
 				return DMA_ERROR_CODE;
 			}
 			sg->dma_address = xen_phys_to_bus(map);
 		} else
 			sg->dma_address = dev_addr;
-		sg->dma_length = sg->length;
+		sg_dma_len(sg) = sg->length;
 	}
 	return nelems;
 }
@@ -533,7 +533,7 @@ xen_swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
 	BUG_ON(dir == DMA_NONE);
 
 	for_each_sg(sgl, sg, nelems, i)
-		xen_unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
+		xen_unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir);
 
 }
 EXPORT_SYMBOL_GPL(xen_swiotlb_unmap_sg_attrs);
@@ -555,7 +555,7 @@ xen_swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
 
 	for_each_sg(sgl, sg, nelems, i)
 		xen_swiotlb_sync_single(hwdev, sg->dma_address,
-					sg->dma_length, dir, target);
+					sg_dma_len(sg), dir, target);
 }
 
 void

drivers/xen/xen-selfballoon.c

@@ -265,8 +265,10 @@ static ssize_t store_selfballooning(struct device *dev,
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
-	err = strict_strtoul(buf, 10, &tmp);
-	if (err || ((tmp != 0) && (tmp != 1)))
+	err = kstrtoul(buf, 10, &tmp);
+	if (err)
+		return err;
+	if ((tmp != 0) && (tmp != 1))
 		return -EINVAL;
 
 	xen_selfballooning_enabled = !!tmp;
@@ -292,8 +294,10 @@ static ssize_t store_selfballoon_interval(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	selfballoon_interval = val;
 	return count;
@@ -314,8 +318,10 @@ static ssize_t store_selfballoon_downhys(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	selfballoon_downhysteresis = val;
 	return count;
@@ -337,8 +343,10 @@ static ssize_t store_selfballoon_uphys(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	selfballoon_uphysteresis = val;
 	return count;
@@ -360,8 +368,10 @@ static ssize_t store_selfballoon_min_usable_mb(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	selfballoon_min_usable_mb = val;
 	return count;
@@ -384,8 +394,10 @@ static ssize_t store_selfballoon_reserved_mb(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	selfballoon_reserved_mb = val;
 	return count;
@@ -410,8 +422,10 @@ static ssize_t store_frontswap_selfshrinking(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &tmp);
-	if (err || ((tmp != 0) && (tmp != 1)))
+	err = kstrtoul(buf, 10, &tmp);
+	if (err)
+		return err;
+	if ((tmp != 0) && (tmp != 1))
 		return -EINVAL;
 	frontswap_selfshrinking = !!tmp;
 	if (!was_enabled && !xen_selfballooning_enabled &&
@@ -437,8 +451,10 @@ static ssize_t store_frontswap_inertia(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	frontswap_inertia = val;
 	frontswap_inertia_counter = val;
@@ -460,8 +476,10 @@ static ssize_t store_frontswap_hysteresis(struct device *dev,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
-	err = strict_strtoul(buf, 10, &val);
-	if (err || val == 0)
+	err = kstrtoul(buf, 10, &val);
+	if (err)
+		return err;
+	if (val == 0)
 		return -EINVAL;
 	frontswap_hysteresis = val;
 	return count;

include/xen/balloon.h

@@ -29,6 +29,9 @@ int alloc_xenballooned_pages(int nr_pages, struct page **pages,
 		bool highmem);
 void free_xenballooned_pages(int nr_pages, struct page **pages);
 
+struct page *get_balloon_scratch_page(void);
+void put_balloon_scratch_page(void);
+
 struct device;
 #ifdef CONFIG_XEN_SELFBALLOONING
 extern int register_xen_selfballooning(struct device *dev);

include/xen/interface/io/tpmif.h

+/******************************************************************************
+ * tpmif.h
+ *
+ * TPM I/O interface for Xen guest OSes, v2
+ *
+ * This file is in the public domain.
+ *
+ */
+
+#ifndef __XEN_PUBLIC_IO_TPMIF_H__
+#define __XEN_PUBLIC_IO_TPMIF_H__
+
+/*
+ * Xenbus state machine
+ *
+ * Device open:
+ *   1. Both ends start in XenbusStateInitialising
+ *   2. Backend transitions to InitWait (frontend does not wait on this step)
+ *   3. Frontend populates ring-ref, event-channel, feature-protocol-v2
+ *   4. Frontend transitions to Initialised
+ *   5. Backend maps grant and event channel, verifies feature-protocol-v2
+ *   6. Backend transitions to Connected
+ *   7. Frontend verifies feature-protocol-v2, transitions to Connected
+ *
+ * Device close:
+ *   1. State is changed to XenbusStateClosing
+ *   2. Frontend transitions to Closed
+ *   3. Backend unmaps grant and event, changes state to InitWait
+ */
+
+enum vtpm_shared_page_state {
+	VTPM_STATE_IDLE,         /* no contents / vTPM idle / cancel complete */
+	VTPM_STATE_SUBMIT,       /* request ready / vTPM working */
+	VTPM_STATE_FINISH,       /* response ready / vTPM idle */
+	VTPM_STATE_CANCEL,       /* cancel requested / vTPM working */
+};
+/* The backend should only change state to IDLE or FINISH, while the
+ * frontend should only change to SUBMIT or CANCEL. */
+
+
+struct vtpm_shared_page {
+	uint32_t length;         /* request/response length in bytes */
+
+	uint8_t state;           /* enum vtpm_shared_page_state */
+	uint8_t locality;        /* for the current request */
+	uint8_t pad;
+
+	uint8_t nr_extra_pages;  /* extra pages for long packets; may be zero */
+	uint32_t extra_pages[0]; /* grant IDs; length in nr_extra_pages */
+};
+
+#endif

include/xen/interface/vcpu.h

@@ -170,4 +170,6 @@ struct vcpu_register_vcpu_info {
 };
 DEFINE_GUEST_HANDLE_STRUCT(vcpu_register_vcpu_info);
 
+/* Send an NMI to the specified VCPU. @extra_arg == NULL. */
+#define VCPUOP_send_nmi             11
 #endif /* __XEN_PUBLIC_VCPU_H__ */

lib/swiotlb.c

@@ -870,13 +870,13 @@ swiotlb_map_sg_attrs(struct device *hwdev, struct scatterlist *sgl, int nelems,
 				swiotlb_full(hwdev, sg->length, dir, 0);
 				swiotlb_unmap_sg_attrs(hwdev, sgl, i, dir,
 						       attrs);
-				sgl[0].dma_length = 0;
+				sg_dma_len(sgl) = 0;
 				return 0;
 			}
 			sg->dma_address = phys_to_dma(hwdev, map);
 		} else
 			sg->dma_address = dev_addr;
-		sg->dma_length = sg->length;
+		sg_dma_len(sg) = sg->length;
 	}
 	return nelems;
 }
@@ -904,7 +904,7 @@ swiotlb_unmap_sg_attrs(struct device *hwdev, struct scatterlist *sgl,
 	BUG_ON(dir == DMA_NONE);
 
 	for_each_sg(sgl, sg, nelems, i)
-		unmap_single(hwdev, sg->dma_address, sg->dma_length, dir);
+		unmap_single(hwdev, sg->dma_address, sg_dma_len(sg), dir);
 
 }
 EXPORT_SYMBOL(swiotlb_unmap_sg_attrs);
@@ -934,7 +934,7 @@ swiotlb_sync_sg(struct device *hwdev, struct scatterlist *sgl,
 
 	for_each_sg(sgl, sg, nelems, i)
 		swiotlb_sync_single(hwdev, sg->dma_address,
-				    sg->dma_length, dir, target);
+				    sg_dma_len(sg), dir, target);
 }
 
 void