[PATCH v3 04/11] x86/xen: add system core suspend and resume callbacks
From: Anchal Agarwal <hidden>
Date: 2020-08-21 22:27:40
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
hibernation support. The callbacks suspend and resume
Xen primitives like shared_info, pvclock and grant table.
These syscore_ops are specifically for domU hibernation.
xen_suspend() calls syscore_suspend() during Xen suspend
operation however, during xen suspend lock_system_sleep()
lock is taken and thus system cannot trigger hibernation.
These system core callbacks will be called only from the
hibernation context.
[Anchal Agarwal: Changelog]:
v1->v2: Edit commit message
Fixed syscore_suspend() to call gnntab_suspend
Removed suspend mode check in syscore_suspend()/
syscore_resume()
v2->v3: Re-introduced check for xen suspend mode to avoid
syscore osp callbacks getting executed during xen
suspend/resume
Signed-off-by: Agarwal Anchal <redacted>
Signed-off-by: Munehisa Kamata <redacted>
---
arch/x86/xen/enlighten_hvm.c | 1 +
arch/x86/xen/suspend.c | 55 ++++++++++++++++++++++++++++++++++++++++++++
include/xen/xen-ops.h | 2 ++
3 files changed, 58 insertions(+)
diff --git a/arch/x86/xen/enlighten_hvm.c b/arch/x86/xen/enlighten_hvm.c
index ff7c69278f63..4b6ad30106dd 100644
--- a/arch/x86/xen/enlighten_hvm.c
+++ b/arch/x86/xen/enlighten_hvm.c@@ -216,6 +216,7 @@ 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..550aa0fc9465 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 +87,53 @@ 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 (is_xen_suspend()) + return 0; + + gnttab_suspend(); + + 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 (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 e8b08734fab1..bad334cd55d7 100644
--- a/include/xen/xen-ops.h
+++ b/include/xen/xen-ops.h@@ -41,6 +41,8 @@ u64 xen_steal_clock(int cpu); int xen_setup_shutdown_event(void); bool is_xen_suspend(void); +void xen_setup_syscore_ops(void); + extern unsigned long *xen_contiguous_bitmap; #if defined(CONFIG_XEN_PV) || defined(CONFIG_ARM) || defined(CONFIG_ARM64)
--
2.16.6