lkml.org 
[lkml]   [2022]   [Sep]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v5 17/30] KVM: Move out KVM arch PM hooks and hardware enable/disable logic
Date
From: Isaku Yamahata <isaku.yamahata@intel.com>

To make clear that those files are default implementation and that KVM/x86
(and other KVM arch in future) will override them, split out those into a
dedicated file. Once conversions for all kvm archs are done, the file will
be deleted.

Signed-off-by: Isaku Yamahata <isaku.yamahata@intel.com>
---
virt/kvm/Makefile.kvm | 2 +-
virt/kvm/kvm_arch.c | 164 ++++++++++++++++++++++++++++++++++++++++++
virt/kvm/kvm_main.c | 160 -----------------------------------------
3 files changed, 165 insertions(+), 161 deletions(-)
create mode 100644 virt/kvm/kvm_arch.c

diff --git a/virt/kvm/Makefile.kvm b/virt/kvm/Makefile.kvm
index 2c27d5d0c367..428b09b3f80a 100644
--- a/virt/kvm/Makefile.kvm
+++ b/virt/kvm/Makefile.kvm
@@ -5,7 +5,7 @@

KVM ?= ../../../virt/kvm

-kvm-y := $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/binary_stats.o
+kvm-y := $(KVM)/kvm_main.o $(KVM)/eventfd.o $(KVM)/binary_stats.o $(KVM)/kvm_arch.o
kvm-$(CONFIG_KVM_VFIO) += $(KVM)/vfio.o
kvm-$(CONFIG_KVM_MMIO) += $(KVM)/coalesced_mmio.o
kvm-$(CONFIG_KVM_ASYNC_PF) += $(KVM)/async_pf.o
diff --git a/virt/kvm/kvm_arch.c b/virt/kvm/kvm_arch.c
new file mode 100644
index 000000000000..bcf8b74144e3
--- /dev/null
+++ b/virt/kvm/kvm_arch.c
@@ -0,0 +1,164 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kvm_arch.c: kvm default arch hooks for hardware enabling/disabling
+ * Copyright (c) 2022 Intel Corporation.
+ *
+ * Author:
+ * Isaku Yamahata <isaku.yamahata@intel.com>
+ * <isaku.yamahata@gmail.com>
+ *
+ * TODO: Delete this file once the conversion of all KVM arch is done.
+ */
+
+#include <linux/kvm_host.h>
+
+static cpumask_t cpus_hardware_enabled = CPU_MASK_NONE;
+static atomic_t hardware_enable_failed;
+
+/*
+ * Called after the VM is otherwise initialized, but just before adding it to
+ * the vm_list.
+ */
+int __weak kvm_arch_post_init_vm(struct kvm *kvm)
+{
+ return 0;
+}
+
+static void hardware_enable_nolock(void *junk)
+{
+ int cpu = raw_smp_processor_id();
+ int r;
+
+ WARN_ON_ONCE(preemptible());
+
+ if (cpumask_test_cpu(cpu, &cpus_hardware_enabled))
+ return;
+
+ cpumask_set_cpu(cpu, &cpus_hardware_enabled);
+
+ r = kvm_arch_hardware_enable();
+
+ if (r) {
+ cpumask_clear_cpu(cpu, &cpus_hardware_enabled);
+ atomic_inc(&hardware_enable_failed);
+ pr_warn("kvm: enabling virtualization on CPU%d failed during %pSb\n",
+ cpu, __builtin_return_address(0));
+ }
+}
+
+static void hardware_disable_nolock(void *junk)
+{
+ int cpu = raw_smp_processor_id();
+
+ WARN_ON_ONCE(preemptible());
+
+ if (!cpumask_test_cpu(cpu, &cpus_hardware_enabled))
+ return;
+ cpumask_clear_cpu(cpu, &cpus_hardware_enabled);
+ kvm_arch_hardware_disable();
+}
+
+/*
+ * Called after the VM is otherwise initialized, but just before adding it to
+ * the vm_list.
+ */
+int __weak kvm_arch_add_vm(struct kvm *kvm, int usage_count)
+{
+ int r = 0;
+
+ if (usage_count != 1)
+ return 0;
+
+ atomic_set(&hardware_enable_failed, 0);
+ on_each_cpu(hardware_enable_nolock, NULL, 1);
+
+ if (atomic_read(&hardware_enable_failed)) {
+ r = -EBUSY;
+ goto err;
+ }
+
+ r = kvm_arch_post_init_vm(kvm);
+err:
+ if (r)
+ on_each_cpu(hardware_disable_nolock, NULL, 1);
+ return r;
+}
+
+int __weak kvm_arch_del_vm(int usage_count)
+{
+ if (usage_count)
+ return 0;
+
+ on_each_cpu(hardware_disable_nolock, NULL, 1);
+ return 0;
+}
+
+int __weak kvm_arch_online_cpu(unsigned int cpu, int usage_count)
+{
+ int ret = 0;
+
+ ret = kvm_arch_check_processor_compat();
+ if (ret)
+ return ret;
+
+ /*
+ * Abort the CPU online process if hardware virtualization cannot
+ * be enabled. Otherwise running VMs would encounter unrecoverable
+ * errors when scheduled to this CPU.
+ */
+ if (usage_count) {
+ WARN_ON_ONCE(atomic_read(&hardware_enable_failed));
+
+ /*
+ * arch callback kvm_arch_hardware_eanble() assumes that
+ * preemption is disabled for historical reason. Disable
+ * preemption until all arch callbacks are fixed.
+ */
+ preempt_disable();
+ hardware_enable_nolock(NULL);
+ preempt_enable();
+ if (atomic_read(&hardware_enable_failed)) {
+ atomic_set(&hardware_enable_failed, 0);
+ ret = -EIO;
+ }
+ }
+ return ret;
+}
+
+int __weak kvm_arch_offline_cpu(unsigned int cpu, int usage_count)
+{
+ if (usage_count) {
+ /*
+ * arch callback kvm_arch_hardware_disable() assumes that
+ * preemption is disabled for historical reason. Disable
+ * preemption until all arch callbacks are fixed.
+ */
+ preempt_disable();
+ hardware_disable_nolock(NULL);
+ preempt_enable();
+ }
+ return 0;
+}
+
+int __weak kvm_arch_reboot(int val)
+{
+ on_each_cpu(hardware_disable_nolock, NULL, 1);
+ return NOTIFY_OK;
+}
+
+int __weak kvm_arch_suspend(int usage_count)
+{
+ if (usage_count)
+ /*
+ * Because kvm_suspend() is called with interrupt disabled, no
+ * need to disable preemption.
+ */
+ hardware_disable_nolock(NULL);
+ return 0;
+}
+
+void __weak kvm_arch_resume(int usage_count)
+{
+ if (usage_count)
+ hardware_enable_nolock(NULL);
+}
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index d7c3bc14691f..b1a09d2d5982 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -102,9 +102,7 @@ EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
DEFINE_MUTEX(kvm_lock);
LIST_HEAD(vm_list);

-static cpumask_var_t cpus_hardware_enabled;
static int kvm_usage_count;
-static atomic_t hardware_enable_failed;

static struct kmem_cache *kvm_vcpu_cache;

@@ -142,8 +140,6 @@ static int kvm_no_compat_open(struct inode *inode, struct file *file)
#define KVM_COMPAT(c) .compat_ioctl = kvm_no_compat_ioctl, \
.open = kvm_no_compat_open
#endif
-static void hardware_enable_nolock(void *junk);
-static void hardware_disable_nolock(void *junk);
static void kvm_del_vm(void);

static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
@@ -1098,120 +1094,6 @@ static int kvm_create_vm_debugfs(struct kvm *kvm, const char *fdname)
return ret;
}

-/*
- * Called after the VM is otherwise initialized, but just before adding it to
- * the vm_list.
- */
-int __weak kvm_arch_post_init_vm(struct kvm *kvm)
-{
- return 0;
-}
-
-/*
- * Called after the VM is otherwise initialized, but just before adding it to
- * the vm_list.
- */
-int __weak kvm_arch_add_vm(struct kvm *kvm, int usage_count)
-{
- int r = 0;
-
- if (usage_count != 1)
- return 0;
-
- atomic_set(&hardware_enable_failed, 0);
- on_each_cpu(hardware_enable_nolock, NULL, 1);
-
- if (atomic_read(&hardware_enable_failed)) {
- r = -EBUSY;
- goto err;
- }
-
- r = kvm_arch_post_init_vm(kvm);
-err:
- if (r)
- on_each_cpu(hardware_disable_nolock, NULL, 1);
- return r;
-}
-
-int __weak kvm_arch_del_vm(int usage_count)
-{
- if (usage_count)
- return 0;
-
- on_each_cpu(hardware_disable_nolock, NULL, 1);
- return 0;
-}
-
-int __weak kvm_arch_online_cpu(unsigned int cpu, int usage_count)
-{
- int ret = 0;
-
- ret = kvm_arch_check_processor_compat();
- if (ret)
- return ret;
-
- /*
- * Abort the CPU online process if hardware virtualization cannot
- * be enabled. Otherwise running VMs would encounter unrecoverable
- * errors when scheduled to this CPU.
- */
- if (usage_count) {
- WARN_ON_ONCE(atomic_read(&hardware_enable_failed));
-
- /*
- * arch callback kvm_arch_hardware_eanble() assumes that
- * preemption is disabled for historical reason. Disable
- * preemption until all arch callbacks are fixed.
- */
- preempt_disable();
- hardware_enable_nolock(NULL);
- preempt_enable();
- if (atomic_read(&hardware_enable_failed)) {
- atomic_set(&hardware_enable_failed, 0);
- ret = -EIO;
- }
- }
- return ret;
-}
-
-int __weak kvm_arch_offline_cpu(unsigned int cpu, int usage_count)
-{
- if (usage_count) {
- /*
- * arch callback kvm_arch_hardware_disable() assumes that
- * preemption is disabled for historical reason. Disable
- * preemption until all arch callbacks are fixed.
- */
- preempt_disable();
- hardware_disable_nolock(NULL);
- preempt_enable();
- }
- return 0;
-}
-
-int __weak kvm_arch_reboot(int val)
-{
- on_each_cpu(hardware_disable_nolock, NULL, 1);
- return NOTIFY_OK;
-}
-
-int __weak kvm_arch_suspend(int usage_count)
-{
- if (usage_count)
- /*
- * Because kvm_suspend() is called with interrupt disabled, no
- * need to disable preemption.
- */
- hardware_disable_nolock(NULL);
- return 0;
-}
-
-void __weak kvm_arch_resume(int usage_count)
-{
- if (usage_count)
- hardware_enable_nolock(NULL);
-}
-
/*
* Called just after removing the VM from the vm_list, but before doing any
* other destruction.
@@ -5106,28 +4988,6 @@ static struct miscdevice kvm_dev = {
&kvm_chardev_ops,
};

-static void hardware_enable_nolock(void *junk)
-{
- int cpu = raw_smp_processor_id();
- int r;
-
- WARN_ON_ONCE(preemptible());
-
- if (cpumask_test_cpu(cpu, cpus_hardware_enabled))
- return;
-
- cpumask_set_cpu(cpu, cpus_hardware_enabled);
-
- r = kvm_arch_hardware_enable();
-
- if (r) {
- cpumask_clear_cpu(cpu, cpus_hardware_enabled);
- atomic_inc(&hardware_enable_failed);
- pr_warn("kvm: enabling virtualization on CPU%d failed during %pSb\n",
- cpu, __builtin_return_address(0));
- }
-}
-
static int kvm_online_cpu(unsigned int cpu)
{
int ret;
@@ -5138,18 +4998,6 @@ static int kvm_online_cpu(unsigned int cpu)
return ret;
}

-static void hardware_disable_nolock(void *junk)
-{
- int cpu = raw_smp_processor_id();
-
- WARN_ON_ONCE(preemptible());
-
- if (!cpumask_test_cpu(cpu, cpus_hardware_enabled))
- return;
- cpumask_clear_cpu(cpu, cpus_hardware_enabled);
- kvm_arch_hardware_disable();
-}
-
static int kvm_offline_cpu(unsigned int cpu)
{
int ret;
@@ -5930,11 +5778,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
if (r)
goto out_irqfd;

- if (!zalloc_cpumask_var(&cpus_hardware_enabled, GFP_KERNEL)) {
- r = -ENOMEM;
- goto out_free_0;
- }
-
r = kvm_arch_hardware_setup(opaque);
if (r < 0)
goto out_free_1;
@@ -6011,8 +5854,6 @@ int kvm_init(void *opaque, unsigned vcpu_size, unsigned vcpu_align,
out_free_2:
kvm_arch_hardware_unsetup();
out_free_1:
- free_cpumask_var(cpus_hardware_enabled);
-out_free_0:
kvm_irqfd_exit();
out_irqfd:
kvm_arch_exit();
@@ -6037,7 +5878,6 @@ void kvm_exit(void)
kvm_arch_hardware_unsetup();
kvm_arch_exit();
kvm_irqfd_exit();
- free_cpumask_var(cpus_hardware_enabled);
kvm_vfio_ops_exit();
}
EXPORT_SYMBOL_GPL(kvm_exit);
--
2.25.1
\
 
 \ /
  Last update: 2022-09-22 20:26    [W:0.272 / U:0.384 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site