[RFC PATCH V2 04/11] x86/xen: add system core suspend and resume callbacks
From: Anchal Agarwal <hidden>
Date: 2020-01-07 23:41:01
Also in:
linux-mm, linux-pm, lkml, xen-devel
Subsystem:
the rest, x86 architecture (32-bit and 64-bit), xen hypervisor interface, xen hypervisor x86 · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Juergen Gross, Stefano Stabellini
From: Munehisa Kamata <redacted> Add Xen PVHVM specific system core callbacks for PM suspend and hibernation support. The callbacks suspend and resume Xen primitives,like shared_info, pvclock and grant table. Note that Xen suspend can handle them in a different manner, but system core callbacks are called from the context. So if the callbacks are called from Xen suspend context, return immediately. Signed-off-by: Agarwal Anchal <redacted> Signed-off-by: Munehisa Kamata <redacted> --- arch/x86/xen/enlighten_hvm.c | 1 + arch/x86/xen/suspend.c | 53 ++++++++++++++++++++++++++++++++++++++++++++ include/xen/xen-ops.h | 3 +++ 3 files changed, 57 insertions(+)
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index 75b1ec7a0fcd..138e71786e03 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c@@ -204,6 +204,7 @@ static void __init xen_hvm_guest_init(void) if (xen_feature(XENFEAT_hvm_callback_vector)) xen_have_vector_callback = 1; + xen_setup_syscore_ops(); xen_hvm_smp_init(); WARN_ON(xen_cpuhp_setup(xen_cpu_up_prepare_hvm, xen_cpu_dead_hvm)); xen_unplug_emulated_devices();
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
index 1d83152c761b..784c4484100b 100644
--- a/arch/x86/xen/suspend.c
+++ b/arch/x86/xen/suspend.c@@ -2,17 +2,22 @@ #include <linux/types.h> #include <linux/tick.h> #include <linux/percpu-defs.h> +#include <linux/syscore_ops.h> +#include <linux/kernel_stat.h> #include <xen/xen.h> #include <xen/interface/xen.h> +#include <xen/interface/memory.h> #include <xen/grant_table.h> #include <xen/events.h> +#include <xen/xen-ops.h> #include <asm/cpufeatures.h> #include <asm/msr-index.h> #include <asm/xen/hypercall.h> #include <asm/xen/page.h> #include <asm/fixmap.h> +#include <asm/pvclock.h> #include "xen-ops.h" #include "mmu.h"
@@ -82,3 +87,51 @@ void xen_arch_suspend(void) on_each_cpu(xen_vcpu_notify_suspend, NULL, 1); } + +static int xen_syscore_suspend(void) +{ + struct xen_remove_from_physmap xrfp; + int ret; + + /* Xen suspend does similar stuffs in its own logic */ + if (xen_suspend_mode_is_xen_suspend()) + return 0; + + xrfp.domid = DOMID_SELF; + xrfp.gpfn = __pa(HYPERVISOR_shared_info) >> PAGE_SHIFT; + + ret = HYPERVISOR_memory_op(XENMEM_remove_from_physmap, &xrfp); + if (!ret) + HYPERVISOR_shared_info = &xen_dummy_shared_info; + + return ret; +} + +static void xen_syscore_resume(void) +{ + /* Xen suspend does similar stuffs in its own logic */ + if (xen_suspend_mode_is_xen_suspend()) + return; + + /* No need to setup vcpu_info as it's already moved off */ + xen_hvm_map_shared_info(); + + pvclock_resume(); + + gnttab_resume(); +} + +/* + * These callbacks will be called with interrupts disabled and when having only + * one CPU online. + */ +static struct syscore_ops xen_hvm_syscore_ops = { + .suspend = xen_syscore_suspend, + .resume = xen_syscore_resume +}; + +void __init xen_setup_syscore_ops(void) +{ + if (xen_hvm_domain()) + register_syscore_ops(&xen_hvm_syscore_ops); +}
diff --git a/include/xen/xen-ops.h b/include/xen/xen-ops.h
index 6c36e161dfd1..3b3992b5b0c2 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h@@ -43,6 +43,9 @@ int xen_setup_shutdown_event(void); bool xen_suspend_mode_is_xen_suspend(void); bool xen_suspend_mode_is_pm_suspend(void); bool xen_suspend_mode_is_pm_hibernation(void); + +void xen_setup_syscore_ops(void); + extern unsigned long *xen_contiguous_bitmap; #if defined(CONFIG_XEN_PV) || defined(CONFIG_ARM) || defined(CONFIG_ARM64)
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2.15.3.AMZN