v4.19.13 snapshot.
diff --git a/arch/arm/xen/Makefile b/arch/arm/xen/Makefile
new file mode 100644
index 0000000..2279521
--- /dev/null
+++ b/arch/arm/xen/Makefile
@@ -0,0 +1,2 @@
+obj-y := enlighten.o hypercall.o grant-table.o p2m.o mm.o
+obj-$(CONFIG_XEN_EFI) += efi.o
diff --git a/arch/arm/xen/efi.c b/arch/arm/xen/efi.c
new file mode 100644
index 0000000..b4d7895
--- /dev/null
+++ b/arch/arm/xen/efi.c
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2015, Linaro Limited, Shannon Zhao
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/efi.h>
+#include <xen/xen-ops.h>
+#include <asm/xen/xen-ops.h>
+
+/* Set XEN EFI runtime services function pointers. Other fields of struct efi,
+ * e.g. efi.systab, will be set like normal EFI.
+ */
+void __init xen_efi_runtime_setup(void)
+{
+ efi.get_time = xen_efi_get_time;
+ efi.set_time = xen_efi_set_time;
+ efi.get_wakeup_time = xen_efi_get_wakeup_time;
+ efi.set_wakeup_time = xen_efi_set_wakeup_time;
+ efi.get_variable = xen_efi_get_variable;
+ efi.get_next_variable = xen_efi_get_next_variable;
+ efi.set_variable = xen_efi_set_variable;
+ efi.query_variable_info = xen_efi_query_variable_info;
+ efi.update_capsule = xen_efi_update_capsule;
+ efi.query_capsule_caps = xen_efi_query_capsule_caps;
+ efi.get_next_high_mono_count = xen_efi_get_next_high_mono_count;
+ efi.reset_system = xen_efi_reset_system;
+}
+EXPORT_SYMBOL_GPL(xen_efi_runtime_setup);
diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
new file mode 100644
index 0000000..07060e5
--- /dev/null
+++ b/arch/arm/xen/enlighten.c
@@ -0,0 +1,477 @@
+#include <xen/xen.h>
+#include <xen/events.h>
+#include <xen/grant_table.h>
+#include <xen/hvm.h>
+#include <xen/interface/vcpu.h>
+#include <xen/interface/xen.h>
+#include <xen/interface/memory.h>
+#include <xen/interface/hvm/params.h>
+#include <xen/features.h>
+#include <xen/platform_pci.h>
+#include <xen/xenbus.h>
+#include <xen/page.h>
+#include <xen/interface/sched.h>
+#include <xen/xen-ops.h>
+#include <asm/xen/hypervisor.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/xen-ops.h>
+#include <asm/system_misc.h>
+#include <asm/efi.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_fdt.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/cpuidle.h>
+#include <linux/cpufreq.h>
+#include <linux/cpu.h>
+#include <linux/console.h>
+#include <linux/pvclock_gtod.h>
+#include <linux/time64.h>
+#include <linux/timekeeping.h>
+#include <linux/timekeeper_internal.h>
+#include <linux/acpi.h>
+
+#include <linux/mm.h>
+
+struct start_info _xen_start_info;
+struct start_info *xen_start_info = &_xen_start_info;
+EXPORT_SYMBOL(xen_start_info);
+
+enum xen_domain_type xen_domain_type = XEN_NATIVE;
+EXPORT_SYMBOL(xen_domain_type);
+
+struct shared_info xen_dummy_shared_info;
+struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
+
+DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
+static struct vcpu_info __percpu *xen_vcpu_info;
+
+/* Linux <-> Xen vCPU id mapping */
+DEFINE_PER_CPU(uint32_t, xen_vcpu_id);
+EXPORT_PER_CPU_SYMBOL(xen_vcpu_id);
+
+/* These are unused until we support booting "pre-ballooned" */
+unsigned long xen_released_pages;
+struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
+
+static __read_mostly unsigned int xen_events_irq;
+
+uint32_t xen_start_flags;
+EXPORT_SYMBOL(xen_start_flags);
+
+int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
+ unsigned long addr,
+ xen_pfn_t *gfn, int nr,
+ int *err_ptr, pgprot_t prot,
+ unsigned domid,
+ struct page **pages)
+{
+ return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
+ prot, domid, pages);
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
+
+/* Not used by XENFEAT_auto_translated guests. */
+int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
+ unsigned long addr,
+ xen_pfn_t gfn, int nr,
+ pgprot_t prot, unsigned domid,
+ struct page **pages)
+{
+ return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
+
+int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
+ int nr, struct page **pages)
+{
+ return xen_xlate_unmap_gfn_range(vma, nr, pages);
+}
+EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
+
+/* Not used by XENFEAT_auto_translated guests. */
+int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
+ unsigned long addr,
+ xen_pfn_t *mfn, int nr,
+ int *err_ptr, pgprot_t prot,
+ unsigned int domid, struct page **pages)
+{
+ return -ENOSYS;
+}
+EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
+
+static void xen_read_wallclock(struct timespec64 *ts)
+{
+ u32 version;
+ struct timespec64 now, ts_monotonic;
+ struct shared_info *s = HYPERVISOR_shared_info;
+ struct pvclock_wall_clock *wall_clock = &(s->wc);
+
+ /* get wallclock at system boot */
+ do {
+ version = wall_clock->version;
+ rmb(); /* fetch version before time */
+ now.tv_sec = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec;
+ now.tv_nsec = wall_clock->nsec;
+ rmb(); /* fetch time before checking version */
+ } while ((wall_clock->version & 1) || (version != wall_clock->version));
+
+ /* time since system boot */
+ ktime_get_ts64(&ts_monotonic);
+ *ts = timespec64_add(now, ts_monotonic);
+}
+
+static int xen_pvclock_gtod_notify(struct notifier_block *nb,
+ unsigned long was_set, void *priv)
+{
+ /* Protected by the calling core code serialization */
+ static struct timespec64 next_sync;
+
+ struct xen_platform_op op;
+ struct timespec64 now, system_time;
+ struct timekeeper *tk = priv;
+
+ now.tv_sec = tk->xtime_sec;
+ now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
+ system_time = timespec64_add(now, tk->wall_to_monotonic);
+
+ /*
+ * We only take the expensive HV call when the clock was set
+ * or when the 11 minutes RTC synchronization time elapsed.
+ */
+ if (!was_set && timespec64_compare(&now, &next_sync) < 0)
+ return NOTIFY_OK;
+
+ op.cmd = XENPF_settime64;
+ op.u.settime64.mbz = 0;
+ op.u.settime64.secs = now.tv_sec;
+ op.u.settime64.nsecs = now.tv_nsec;
+ op.u.settime64.system_time = timespec64_to_ns(&system_time);
+ (void)HYPERVISOR_platform_op(&op);
+
+ /*
+ * Move the next drift compensation time 11 minutes
+ * ahead. That's emulating the sync_cmos_clock() update for
+ * the hardware RTC.
+ */
+ next_sync = now;
+ next_sync.tv_sec += 11 * 60;
+
+ return NOTIFY_OK;
+}
+
+static struct notifier_block xen_pvclock_gtod_notifier = {
+ .notifier_call = xen_pvclock_gtod_notify,
+};
+
+static int xen_starting_cpu(unsigned int cpu)
+{
+ struct vcpu_register_vcpu_info info;
+ struct vcpu_info *vcpup;
+ int err;
+
+ /*
+ * VCPUOP_register_vcpu_info cannot be called twice for the same
+ * vcpu, so if vcpu_info is already registered, just get out. This
+ * can happen with cpu-hotplug.
+ */
+ if (per_cpu(xen_vcpu, cpu) != NULL)
+ goto after_register_vcpu_info;
+
+ pr_info("Xen: initializing cpu%d\n", cpu);
+ vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
+
+ info.mfn = virt_to_gfn(vcpup);
+ info.offset = xen_offset_in_page(vcpup);
+
+ err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu),
+ &info);
+ BUG_ON(err);
+ per_cpu(xen_vcpu, cpu) = vcpup;
+
+ xen_setup_runstate_info(cpu);
+
+after_register_vcpu_info:
+ enable_percpu_irq(xen_events_irq, 0);
+ return 0;
+}
+
+static int xen_dying_cpu(unsigned int cpu)
+{
+ disable_percpu_irq(xen_events_irq);
+ return 0;
+}
+
+void xen_reboot(int reason)
+{
+ struct sched_shutdown r = { .reason = reason };
+ int rc;
+
+ rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
+ BUG_ON(rc);
+}
+
+static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
+{
+ xen_reboot(SHUTDOWN_reboot);
+}
+
+
+static void xen_power_off(void)
+{
+ xen_reboot(SHUTDOWN_poweroff);
+}
+
+static irqreturn_t xen_arm_callback(int irq, void *arg)
+{
+ xen_hvm_evtchn_do_upcall();
+ return IRQ_HANDLED;
+}
+
+static __initdata struct {
+ const char *compat;
+ const char *prefix;
+ const char *version;
+ bool found;
+} hyper_node = {"xen,xen", "xen,xen-", NULL, false};
+
+static int __init fdt_find_hyper_node(unsigned long node, const char *uname,
+ int depth, void *data)
+{
+ const void *s = NULL;
+ int len;
+
+ if (depth != 1 || strcmp(uname, "hypervisor") != 0)
+ return 0;
+
+ if (of_flat_dt_is_compatible(node, hyper_node.compat))
+ hyper_node.found = true;
+
+ s = of_get_flat_dt_prop(node, "compatible", &len);
+ if (strlen(hyper_node.prefix) + 3 < len &&
+ !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix)))
+ hyper_node.version = s + strlen(hyper_node.prefix);
+
+ /*
+ * Check if Xen supports EFI by checking whether there is the
+ * "/hypervisor/uefi" node in DT. If so, runtime services are available
+ * through proxy functions (e.g. in case of Xen dom0 EFI implementation
+ * they call special hypercall which executes relevant EFI functions)
+ * and that is why they are always enabled.
+ */
+ if (IS_ENABLED(CONFIG_XEN_EFI)) {
+ if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) &&
+ !efi_runtime_disabled())
+ set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
+ }
+
+ return 0;
+}
+
+/*
+ * see Documentation/devicetree/bindings/arm/xen.txt for the
+ * documentation of the Xen Device Tree format.
+ */
+#define GRANT_TABLE_PHYSADDR 0
+void __init xen_early_init(void)
+{
+ of_scan_flat_dt(fdt_find_hyper_node, NULL);
+ if (!hyper_node.found) {
+ pr_debug("No Xen support\n");
+ return;
+ }
+
+ if (hyper_node.version == NULL) {
+ pr_debug("Xen version not found\n");
+ return;
+ }
+
+ pr_info("Xen %s support found\n", hyper_node.version);
+
+ xen_domain_type = XEN_HVM_DOMAIN;
+
+ xen_setup_features();
+
+ if (xen_feature(XENFEAT_dom0))
+ xen_start_flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
+
+ if (!console_set_on_cmdline && !xen_initial_domain())
+ add_preferred_console("hvc", 0, NULL);
+}
+
+static void __init xen_acpi_guest_init(void)
+{
+#ifdef CONFIG_ACPI
+ struct xen_hvm_param a;
+ int interrupt, trigger, polarity;
+
+ a.domid = DOMID_SELF;
+ a.index = HVM_PARAM_CALLBACK_IRQ;
+
+ if (HYPERVISOR_hvm_op(HVMOP_get_param, &a)
+ || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) {
+ xen_events_irq = 0;
+ return;
+ }
+
+ interrupt = a.value & 0xff;
+ trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE
+ : ACPI_LEVEL_SENSITIVE;
+ polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW
+ : ACPI_ACTIVE_HIGH;
+ xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity);
+#endif
+}
+
+static void __init xen_dt_guest_init(void)
+{
+ struct device_node *xen_node;
+
+ xen_node = of_find_compatible_node(NULL, NULL, "xen,xen");
+ if (!xen_node) {
+ pr_err("Xen support was detected before, but it has disappeared\n");
+ return;
+ }
+
+ xen_events_irq = irq_of_parse_and_map(xen_node, 0);
+}
+
+static int __init xen_guest_init(void)
+{
+ struct xen_add_to_physmap xatp;
+ struct shared_info *shared_info_page = NULL;
+ int cpu;
+
+ if (!xen_domain())
+ return 0;
+
+ if (!acpi_disabled)
+ xen_acpi_guest_init();
+ else
+ xen_dt_guest_init();
+
+ if (!xen_events_irq) {
+ pr_err("Xen event channel interrupt not found\n");
+ return -ENODEV;
+ }
+
+ /*
+ * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI
+ * parameters are found. Force enable runtime services.
+ */
+ if (efi_enabled(EFI_RUNTIME_SERVICES))
+ xen_efi_runtime_setup();
+
+ shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
+
+ if (!shared_info_page) {
+ pr_err("not enough memory\n");
+ return -ENOMEM;
+ }
+ xatp.domid = DOMID_SELF;
+ xatp.idx = 0;
+ xatp.space = XENMAPSPACE_shared_info;
+ xatp.gpfn = virt_to_gfn(shared_info_page);
+ if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
+ BUG();
+
+ HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
+
+ /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
+ * page, we use it in the event channel upcall and in some pvclock
+ * related functions.
+ * The shared info contains exactly 1 CPU (the boot CPU). The guest
+ * is required to use VCPUOP_register_vcpu_info to place vcpu info
+ * for secondary CPUs as they are brought up.
+ * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
+ */
+ xen_vcpu_info = alloc_percpu(struct vcpu_info);
+ if (xen_vcpu_info == NULL)
+ return -ENOMEM;
+
+ /* Direct vCPU id mapping for ARM guests. */
+ for_each_possible_cpu(cpu)
+ per_cpu(xen_vcpu_id, cpu) = cpu;
+
+ xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames();
+ if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn,
+ &xen_auto_xlat_grant_frames.vaddr,
+ xen_auto_xlat_grant_frames.count)) {
+ free_percpu(xen_vcpu_info);
+ return -ENOMEM;
+ }
+ gnttab_init();
+ if (!xen_initial_domain())
+ xenbus_probe(NULL);
+
+ /*
+ * Making sure board specific code will not set up ops for
+ * cpu idle and cpu freq.
+ */
+ disable_cpuidle();
+ disable_cpufreq();
+
+ xen_init_IRQ();
+
+ if (request_percpu_irq(xen_events_irq, xen_arm_callback,
+ "events", &xen_vcpu)) {
+ pr_err("Error request IRQ %d\n", xen_events_irq);
+ return -EINVAL;
+ }
+
+ xen_time_setup_guest();
+
+ if (xen_initial_domain())
+ pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier);
+
+ return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING,
+ "arm/xen:starting", xen_starting_cpu,
+ xen_dying_cpu);
+}
+early_initcall(xen_guest_init);
+
+static int __init xen_pm_init(void)
+{
+ if (!xen_domain())
+ return -ENODEV;
+
+ pm_power_off = xen_power_off;
+ arm_pm_restart = xen_restart;
+ if (!xen_initial_domain()) {
+ struct timespec64 ts;
+ xen_read_wallclock(&ts);
+ do_settimeofday64(&ts);
+ }
+
+ return 0;
+}
+late_initcall(xen_pm_init);
+
+
+/* empty stubs */
+void xen_arch_pre_suspend(void) { }
+void xen_arch_post_suspend(int suspend_cancelled) { }
+void xen_timer_resume(void) { }
+void xen_arch_resume(void) { }
+void xen_arch_suspend(void) { }
+
+
+/* In the hypercall.S file. */
+EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
+EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
+EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op);
+EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
+EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist);
+EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op);
+EXPORT_SYMBOL_GPL(privcmd_call);
diff --git a/arch/arm/xen/grant-table.c b/arch/arm/xen/grant-table.c
new file mode 100644
index 0000000..91cf08b
--- /dev/null
+++ b/arch/arm/xen/grant-table.c
@@ -0,0 +1,58 @@
+/******************************************************************************
+ * grant_table.c
+ * ARM specific part
+ *
+ * Granting foreign access to our memory reservation.
+ *
+ * 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; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include <xen/interface/xen.h>
+#include <xen/page.h>
+#include <xen/grant_table.h>
+
+int arch_gnttab_map_shared(xen_pfn_t *frames, unsigned long nr_gframes,
+ unsigned long max_nr_gframes,
+ void **__shared)
+{
+ return -ENOSYS;
+}
+
+void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
+{
+ return;
+}
+
+int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
+ unsigned long max_nr_gframes,
+ grant_status_t **__shared)
+{
+ return -ENOSYS;
+}
+
+int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
+{
+ return 0;
+}
diff --git a/arch/arm/xen/hypercall.S b/arch/arm/xen/hypercall.S
new file mode 100644
index 0000000..b0b80c0
--- /dev/null
+++ b/arch/arm/xen/hypercall.S
@@ -0,0 +1,123 @@
+/******************************************************************************
+ * hypercall.S
+ *
+ * Xen hypercall wrappers
+ *
+ * Stefano Stabellini <stefano.stabellini@eu.citrix.com>, Citrix, 2012
+ *
+ * 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; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+/*
+ * The Xen hypercall calling convention is very similar to the ARM
+ * procedure calling convention: the first paramter is passed in r0, the
+ * second in r1, the third in r2 and the fourth in r3. Considering that
+ * Xen hypercalls have 5 arguments at most, the fifth paramter is passed
+ * in r4, differently from the procedure calling convention of using the
+ * stack for that case.
+ *
+ * The hypercall number is passed in r12.
+ *
+ * The return value is in r0.
+ *
+ * The hvc ISS is required to be 0xEA1, that is the Xen specific ARM
+ * hypercall tag.
+ */
+
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/opcodes-virt.h>
+#include <xen/interface/xen.h>
+
+
+#define XEN_IMM 0xEA1
+
+#define HYPERCALL_SIMPLE(hypercall) \
+ENTRY(HYPERVISOR_##hypercall) \
+ mov r12, #__HYPERVISOR_##hypercall; \
+ __HVC(XEN_IMM); \
+ ret lr; \
+ENDPROC(HYPERVISOR_##hypercall)
+
+#define HYPERCALL0 HYPERCALL_SIMPLE
+#define HYPERCALL1 HYPERCALL_SIMPLE
+#define HYPERCALL2 HYPERCALL_SIMPLE
+#define HYPERCALL3 HYPERCALL_SIMPLE
+#define HYPERCALL4 HYPERCALL_SIMPLE
+
+#define HYPERCALL5(hypercall) \
+ENTRY(HYPERVISOR_##hypercall) \
+ stmdb sp!, {r4} \
+ ldr r4, [sp, #4] \
+ mov r12, #__HYPERVISOR_##hypercall; \
+ __HVC(XEN_IMM); \
+ ldm sp!, {r4} \
+ ret lr \
+ENDPROC(HYPERVISOR_##hypercall)
+
+ .text
+
+HYPERCALL2(xen_version);
+HYPERCALL3(console_io);
+HYPERCALL3(grant_table_op);
+HYPERCALL2(sched_op);
+HYPERCALL2(event_channel_op);
+HYPERCALL2(hvm_op);
+HYPERCALL2(memory_op);
+HYPERCALL2(physdev_op);
+HYPERCALL3(vcpu_op);
+HYPERCALL1(tmem_op);
+HYPERCALL1(platform_op_raw);
+HYPERCALL2(multicall);
+HYPERCALL2(vm_assist);
+HYPERCALL3(dm_op);
+
+ENTRY(privcmd_call)
+ stmdb sp!, {r4}
+ mov r12, r0
+ mov r0, r1
+ mov r1, r2
+ mov r2, r3
+ ldr r3, [sp, #8]
+ /*
+ * Privcmd calls are issued by the userspace. We need to allow the
+ * kernel to access the userspace memory before issuing the hypercall.
+ */
+ uaccess_enable r4
+
+ /* r4 is loaded now as we use it as scratch register before */
+ ldr r4, [sp, #4]
+ __HVC(XEN_IMM)
+
+ /*
+ * Disable userspace access from kernel. This is fine to do it
+ * unconditionally as no set_fs(KERNEL_DS)/set_fs(get_ds()) is
+ * called before.
+ */
+ uaccess_disable r4
+
+ ldm sp!, {r4}
+ ret lr
+ENDPROC(privcmd_call);
diff --git a/arch/arm/xen/mm.c b/arch/arm/xen/mm.c
new file mode 100644
index 0000000..785d2a5
--- /dev/null
+++ b/arch/arm/xen/mm.c
@@ -0,0 +1,204 @@
+#include <linux/cpu.h>
+#include <linux/dma-mapping.h>
+#include <linux/bootmem.h>
+#include <linux/gfp.h>
+#include <linux/highmem.h>
+#include <linux/export.h>
+#include <linux/memblock.h>
+#include <linux/of_address.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/dma-mapping.h>
+#include <linux/vmalloc.h>
+#include <linux/swiotlb.h>
+
+#include <xen/xen.h>
+#include <xen/interface/grant_table.h>
+#include <xen/interface/memory.h>
+#include <xen/page.h>
+#include <xen/swiotlb-xen.h>
+
+#include <asm/cacheflush.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/interface.h>
+
+unsigned long xen_get_swiotlb_free_pages(unsigned int order)
+{
+ struct memblock_region *reg;
+ gfp_t flags = __GFP_NOWARN|__GFP_KSWAPD_RECLAIM;
+
+ for_each_memblock(memory, reg) {
+ if (reg->base < (phys_addr_t)0xffffffff) {
+ flags |= __GFP_DMA;
+ break;
+ }
+ }
+ return __get_free_pages(flags, order);
+}
+
+enum dma_cache_op {
+ DMA_UNMAP,
+ DMA_MAP,
+};
+static bool hypercall_cflush = false;
+
+/* functions called by SWIOTLB */
+
+static void dma_cache_maint(dma_addr_t handle, unsigned long offset,
+ size_t size, enum dma_data_direction dir, enum dma_cache_op op)
+{
+ struct gnttab_cache_flush cflush;
+ unsigned long xen_pfn;
+ size_t left = size;
+
+ xen_pfn = (handle >> XEN_PAGE_SHIFT) + offset / XEN_PAGE_SIZE;
+ offset %= XEN_PAGE_SIZE;
+
+ do {
+ size_t len = left;
+
+ /* buffers in highmem or foreign pages cannot cross page
+ * boundaries */
+ if (len + offset > XEN_PAGE_SIZE)
+ len = XEN_PAGE_SIZE - offset;
+
+ cflush.op = 0;
+ cflush.a.dev_bus_addr = xen_pfn << XEN_PAGE_SHIFT;
+ cflush.offset = offset;
+ cflush.length = len;
+
+ if (op == DMA_UNMAP && dir != DMA_TO_DEVICE)
+ cflush.op = GNTTAB_CACHE_INVAL;
+ if (op == DMA_MAP) {
+ if (dir == DMA_FROM_DEVICE)
+ cflush.op = GNTTAB_CACHE_INVAL;
+ else
+ cflush.op = GNTTAB_CACHE_CLEAN;
+ }
+ if (cflush.op)
+ HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1);
+
+ offset = 0;
+ xen_pfn++;
+ left -= len;
+ } while (left);
+}
+
+static void __xen_dma_page_dev_to_cpu(struct device *hwdev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir)
+{
+ dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_UNMAP);
+}
+
+static void __xen_dma_page_cpu_to_dev(struct device *hwdev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir)
+{
+ dma_cache_maint(handle & PAGE_MASK, handle & ~PAGE_MASK, size, dir, DMA_MAP);
+}
+
+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, unsigned long attrs)
+{
+ if (is_device_dma_coherent(hwdev))
+ return;
+ if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+ return;
+
+ __xen_dma_page_cpu_to_dev(hwdev, dev_addr, size, dir);
+}
+
+void __xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+
+{
+ if (is_device_dma_coherent(hwdev))
+ return;
+ if (attrs & DMA_ATTR_SKIP_CPU_SYNC)
+ return;
+
+ __xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
+}
+
+void __xen_dma_sync_single_for_cpu(struct device *hwdev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ if (is_device_dma_coherent(hwdev))
+ return;
+ __xen_dma_page_dev_to_cpu(hwdev, handle, size, dir);
+}
+
+void __xen_dma_sync_single_for_device(struct device *hwdev,
+ dma_addr_t handle, size_t size, enum dma_data_direction dir)
+{
+ if (is_device_dma_coherent(hwdev))
+ return;
+ __xen_dma_page_cpu_to_dev(hwdev, handle, size, dir);
+}
+
+bool xen_arch_need_swiotlb(struct device *dev,
+ phys_addr_t phys,
+ dma_addr_t dev_addr)
+{
+ unsigned int xen_pfn = XEN_PFN_DOWN(phys);
+ unsigned int bfn = XEN_PFN_DOWN(dev_addr);
+
+ /*
+ * The swiotlb buffer should be used if
+ * - Xen doesn't have the cache flush hypercall
+ * - The Linux page refers to foreign memory
+ * - The device doesn't support coherent DMA request
+ *
+ * The Linux page may be spanned acrros multiple Xen page, although
+ * it's not possible to have a mix of local and foreign Xen page.
+ * Furthermore, range_straddles_page_boundary is already checking
+ * if buffer is physically contiguous in the host RAM.
+ *
+ * Therefore we only need to check the first Xen page to know if we
+ * require a bounce buffer because the device doesn't support coherent
+ * memory and we are not able to flush the cache.
+ */
+ return (!hypercall_cflush && (xen_pfn != bfn) &&
+ !is_device_dma_coherent(dev));
+}
+
+int xen_create_contiguous_region(phys_addr_t pstart, unsigned int order,
+ unsigned int address_bits,
+ dma_addr_t *dma_handle)
+{
+ if (!xen_initial_domain())
+ return -EINVAL;
+
+ /* we assume that dom0 is mapped 1:1 for now */
+ *dma_handle = pstart;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(xen_create_contiguous_region);
+
+void xen_destroy_contiguous_region(phys_addr_t pstart, unsigned int order)
+{
+ return;
+}
+EXPORT_SYMBOL_GPL(xen_destroy_contiguous_region);
+
+const struct dma_map_ops *xen_dma_ops;
+EXPORT_SYMBOL(xen_dma_ops);
+
+int __init xen_mm_init(void)
+{
+ struct gnttab_cache_flush cflush;
+ if (!xen_initial_domain())
+ return 0;
+ xen_swiotlb_init(1, false);
+ xen_dma_ops = &xen_swiotlb_dma_ops;
+
+ cflush.op = 0;
+ cflush.a.dev_bus_addr = 0;
+ cflush.offset = 0;
+ cflush.length = 0;
+ if (HYPERVISOR_grant_table_op(GNTTABOP_cache_flush, &cflush, 1) != -ENOSYS)
+ hypercall_cflush = true;
+ return 0;
+}
+arch_initcall(xen_mm_init);
diff --git a/arch/arm/xen/p2m.c b/arch/arm/xen/p2m.c
new file mode 100644
index 0000000..0641ba5
--- /dev/null
+++ b/arch/arm/xen/p2m.c
@@ -0,0 +1,177 @@
+#include <linux/bootmem.h>
+#include <linux/gfp.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/dma-mapping.h>
+#include <linux/vmalloc.h>
+#include <linux/swiotlb.h>
+
+#include <xen/xen.h>
+#include <xen/interface/memory.h>
+#include <xen/page.h>
+#include <xen/swiotlb-xen.h>
+
+#include <asm/cacheflush.h>
+#include <asm/xen/hypercall.h>
+#include <asm/xen/interface.h>
+
+struct xen_p2m_entry {
+ unsigned long pfn;
+ unsigned long mfn;
+ unsigned long nr_pages;
+ struct rb_node rbnode_phys;
+};
+
+static rwlock_t p2m_lock;
+struct rb_root phys_to_mach = RB_ROOT;
+EXPORT_SYMBOL_GPL(phys_to_mach);
+
+static int xen_add_phys_to_mach_entry(struct xen_p2m_entry *new)
+{
+ struct rb_node **link = &phys_to_mach.rb_node;
+ struct rb_node *parent = NULL;
+ struct xen_p2m_entry *entry;
+ int rc = 0;
+
+ while (*link) {
+ parent = *link;
+ entry = rb_entry(parent, struct xen_p2m_entry, rbnode_phys);
+
+ if (new->pfn == entry->pfn)
+ goto err_out;
+
+ if (new->pfn < entry->pfn)
+ link = &(*link)->rb_left;
+ else
+ link = &(*link)->rb_right;
+ }
+ rb_link_node(&new->rbnode_phys, parent, link);
+ rb_insert_color(&new->rbnode_phys, &phys_to_mach);
+ goto out;
+
+err_out:
+ rc = -EINVAL;
+ pr_warn("%s: cannot add pfn=%pa -> mfn=%pa: pfn=%pa -> mfn=%pa already exists\n",
+ __func__, &new->pfn, &new->mfn, &entry->pfn, &entry->mfn);
+out:
+ return rc;
+}
+
+unsigned long __pfn_to_mfn(unsigned long pfn)
+{
+ struct rb_node *n = phys_to_mach.rb_node;
+ struct xen_p2m_entry *entry;
+ unsigned long irqflags;
+
+ read_lock_irqsave(&p2m_lock, irqflags);
+ while (n) {
+ entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
+ if (entry->pfn <= pfn &&
+ entry->pfn + entry->nr_pages > pfn) {
+ read_unlock_irqrestore(&p2m_lock, irqflags);
+ return entry->mfn + (pfn - entry->pfn);
+ }
+ if (pfn < entry->pfn)
+ n = n->rb_left;
+ else
+ n = n->rb_right;
+ }
+ read_unlock_irqrestore(&p2m_lock, irqflags);
+
+ return INVALID_P2M_ENTRY;
+}
+EXPORT_SYMBOL_GPL(__pfn_to_mfn);
+
+int set_foreign_p2m_mapping(struct gnttab_map_grant_ref *map_ops,
+ struct gnttab_map_grant_ref *kmap_ops,
+ struct page **pages, unsigned int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ if (map_ops[i].status)
+ continue;
+ set_phys_to_machine(map_ops[i].host_addr >> XEN_PAGE_SHIFT,
+ map_ops[i].dev_bus_addr >> XEN_PAGE_SHIFT);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(set_foreign_p2m_mapping);
+
+int clear_foreign_p2m_mapping(struct gnttab_unmap_grant_ref *unmap_ops,
+ struct gnttab_unmap_grant_ref *kunmap_ops,
+ struct page **pages, unsigned int count)
+{
+ int i;
+
+ for (i = 0; i < count; i++) {
+ set_phys_to_machine(unmap_ops[i].host_addr >> XEN_PAGE_SHIFT,
+ INVALID_P2M_ENTRY);
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(clear_foreign_p2m_mapping);
+
+bool __set_phys_to_machine_multi(unsigned long pfn,
+ unsigned long mfn, unsigned long nr_pages)
+{
+ int rc;
+ unsigned long irqflags;
+ struct xen_p2m_entry *p2m_entry;
+ struct rb_node *n = phys_to_mach.rb_node;
+
+ if (mfn == INVALID_P2M_ENTRY) {
+ write_lock_irqsave(&p2m_lock, irqflags);
+ while (n) {
+ p2m_entry = rb_entry(n, struct xen_p2m_entry, rbnode_phys);
+ if (p2m_entry->pfn <= pfn &&
+ p2m_entry->pfn + p2m_entry->nr_pages > pfn) {
+ rb_erase(&p2m_entry->rbnode_phys, &phys_to_mach);
+ write_unlock_irqrestore(&p2m_lock, irqflags);
+ kfree(p2m_entry);
+ return true;
+ }
+ if (pfn < p2m_entry->pfn)
+ n = n->rb_left;
+ else
+ n = n->rb_right;
+ }
+ write_unlock_irqrestore(&p2m_lock, irqflags);
+ return true;
+ }
+
+ p2m_entry = kzalloc(sizeof(*p2m_entry), GFP_NOWAIT);
+ if (!p2m_entry)
+ return false;
+
+ p2m_entry->pfn = pfn;
+ p2m_entry->nr_pages = nr_pages;
+ p2m_entry->mfn = mfn;
+
+ write_lock_irqsave(&p2m_lock, irqflags);
+ rc = xen_add_phys_to_mach_entry(p2m_entry);
+ if (rc < 0) {
+ write_unlock_irqrestore(&p2m_lock, irqflags);
+ return false;
+ }
+ write_unlock_irqrestore(&p2m_lock, irqflags);
+ return true;
+}
+EXPORT_SYMBOL_GPL(__set_phys_to_machine_multi);
+
+bool __set_phys_to_machine(unsigned long pfn, unsigned long mfn)
+{
+ return __set_phys_to_machine_multi(pfn, mfn, 1);
+}
+EXPORT_SYMBOL_GPL(__set_phys_to_machine);
+
+static int p2m_init(void)
+{
+ rwlock_init(&p2m_lock);
+ return 0;
+}
+arch_initcall(p2m_init);