diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index b1fa8f11c95bac4b547d6b5d7ab2f159c28c8631..1c9c973a7dd9aef4d10abbed638147a539f5dd5b 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -412,6 +412,8 @@ struct kvm {
#endif
long tlbs_dirty;
struct list_head devices;
+ struct dentry *debugfs_dentry;
+ struct kvm_stat_data **debugfs_stat_data;
};
#define kvm_err(fmt, ...) \
@@ -991,6 +993,11 @@ enum kvm_stat_kind {
KVM_STAT_VCPU,
};
+struct kvm_stat_data {
+ int offset;
+ struct kvm *kvm;
+};
+
struct kvm_stats_debugfs_item {
const char *name;
int offset;
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index dd4ac9d9e8f5c71abd930e1ed079b4c52834cd51..37af23052470eff99b2c3a3fdcf05898c7312602 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -63,6 +63,9 @@
#define CREATE_TRACE_POINTS
#include <trace/events/kvm.h>
+/* Worst case buffer size needed for holding an integer. */
+#define ITOA_MAX_LEN 12
+
MODULE_AUTHOR("Qumranet");
MODULE_LICENSE("GPL");
@@ -100,6 +103,9 @@ static __read_mostly struct preempt_ops kvm_preempt_ops;
struct dentry *kvm_debugfs_dir;
EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
+static int kvm_debugfs_num_entries;
+static const struct file_operations *stat_fops_per_vm[];
+
static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
unsigned long arg);
#ifdef CONFIG_KVM_COMPAT
@@ -542,6 +548,58 @@ static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
kvfree(slots);
}
+static void kvm_destroy_vm_debugfs(struct kvm *kvm)
+{
+ int i;
+
+ if (!kvm->debugfs_dentry)
+ return;
+
+ debugfs_remove_recursive(kvm->debugfs_dentry);
+
+ for (i = 0; i < kvm_debugfs_num_entries; i++)
+ kfree(kvm->debugfs_stat_data[i]);
+ kfree(kvm->debugfs_stat_data);
+}
+
+static int kvm_create_vm_debugfs(struct kvm *kvm, int fd)
+{
+ char dir_name[ITOA_MAX_LEN * 2];
+ struct kvm_stat_data *stat_data;
+ struct kvm_stats_debugfs_item *p;
+
+ if (!debugfs_initialized())
+ return 0;
+
+ snprintf(dir_name, sizeof(dir_name), "%d-%d", task_pid_nr(current), fd);
+ kvm->debugfs_dentry = debugfs_create_dir(dir_name,
+ kvm_debugfs_dir);
+ if (!kvm->debugfs_dentry)
+ return -ENOMEM;
+
+ kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
+ sizeof(*kvm->debugfs_stat_data),
+ GFP_KERNEL);
+ if (!kvm->debugfs_stat_data)
+ return -ENOMEM;
+
+ for (p = debugfs_entries; p->name; p++) {
+ stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL);
+ if (!stat_data)
+ return -ENOMEM;
+
+ stat_data->kvm = kvm;
+ stat_data->offset = p->offset;
+ kvm->debugfs_stat_data[p - debugfs_entries] = stat_data;
+ if (!debugfs_create_file(p->name, 0444,
+ kvm->debugfs_dentry,
+ stat_data,
+ stat_fops_per_vm[p->kind]))
+ return -ENOMEM;
+ }
+ return 0;
+}
+
static struct kvm *kvm_create_vm(unsigned long type)
{
int r, i;
@@ -647,6 +705,7 @@ static void kvm_destroy_vm(struct kvm *kvm)
int i;
struct mm_struct *mm = kvm->mm;
+ kvm_destroy_vm_debugfs(kvm);
kvm_arch_sync_events(kvm);
spin_lock(&kvm_lock);
list_del(&kvm->vm_list);
@@ -2999,8 +3058,15 @@ static int kvm_dev_ioctl_create_vm(unsigned long type)
}
#endif
r = anon_inode_getfd("kvm-vm", &kvm_vm_fops, kvm, O_RDWR | O_CLOEXEC);
- if (r < 0)
+ if (r < 0) {
kvm_put_kvm(kvm);
+ return r;
+ }
+
+ if (kvm_create_vm_debugfs(kvm, r) < 0) {
+ kvm_put_kvm(kvm);
+ return -ENOMEM;
+ }
return r;
}
@@ -3425,15 +3491,114 @@ static struct notifier_block kvm_cpu_notifier = {
.notifier_call = kvm_cpu_hotplug,
};
+static int kvm_debugfs_open(struct inode *inode, struct file *file,
+ int (*get)(void *, u64 *), int (*set)(void *, u64),
+ const char *fmt)
+{
+ struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
+ inode->i_private;
+
+ /* The debugfs files are a reference to the kvm struct which
+ * is still valid when kvm_destroy_vm is called.
+ * To avoid the race between open and the removal of the debugfs
+ * directory we test against the users count.
+ */
+ if (!atomic_add_unless(&stat_data->kvm->users_count, 1, 0))
+ return -ENOENT;
+
+ if (simple_attr_open(inode, file, get, set, fmt)) {
+ kvm_put_kvm(stat_data->kvm);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int kvm_debugfs_release(struct inode *inode, struct file *file)
+{
+ struct kvm_stat_data *stat_data = (struct kvm_stat_data *)
+ inode->i_private;
+
+ simple_attr_release(inode, file);
+ kvm_put_kvm(stat_data->kvm);
+
+ return 0;
+}
+
+static int vm_stat_get_per_vm(void *data, u64 *val)
+{
+ struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
+
+ *val = *(u32 *)((void *)stat_data->kvm + stat_data->offset);
+
+ return 0;
+}
+
+static int vm_stat_get_per_vm_open(struct inode *inode, struct file *file)
+{
+ __simple_attr_check_format("%llu\n", 0ull);
+ return kvm_debugfs_open(inode, file, vm_stat_get_per_vm,
+ NULL, "%llu\n");
+}
+
+static const struct file_operations vm_stat_get_per_vm_fops = {
+ .owner = THIS_MODULE,
+ .open = vm_stat_get_per_vm_open,
+ .release = kvm_debugfs_release,
+ .read = simple_attr_read,
+ .write = simple_attr_write,
+ .llseek = generic_file_llseek,
+};
+
+static int vcpu_stat_get_per_vm(void *data, u64 *val)
+{
+ int i;
+ struct kvm_stat_data *stat_data = (struct kvm_stat_data *)data;
+ struct kvm_vcpu *vcpu;
+
+ *val = 0;
+
+ kvm_for_each_vcpu(i, vcpu, stat_data->kvm)
+ *val += *(u32 *)((void *)vcpu + stat_data->offset);
+
+ return 0;
+}
+
+static int vcpu_stat_get_per_vm_open(struct inode *inode, struct file *file)
+{
+ __simple_attr_check_format("%llu\n", 0ull);
+ return kvm_debugfs_open(inode, file, vcpu_stat_get_per_vm,
+ NULL, "%llu\n");
+}
+
+static const struct file_operations vcpu_stat_get_per_vm_fops = {
+ .owner = THIS_MODULE,
+ .open = vcpu_stat_get_per_vm_open,
+ .release = kvm_debugfs_release,
+ .read = simple_attr_read,
+ .write = simple_attr_write,
+ .llseek = generic_file_llseek,
+};
+
+static const struct file_operations *stat_fops_per_vm[] = {
+ [KVM_STAT_VCPU] = &vcpu_stat_get_per_vm_fops,
+ [KVM_STAT_VM] = &vm_stat_get_per_vm_fops,
+};
+
static int vm_stat_get(void *_offset, u64 *val)
{
unsigned offset = (long)_offset;
struct kvm *kvm;
+ struct kvm_stat_data stat_tmp = {.offset = offset};
+ u64 tmp_val;
*val = 0;
spin_lock(&kvm_lock);
- list_for_each_entry(kvm, &vm_list, vm_list)
- *val += *(u32 *)((void *)kvm + offset);
+ list_for_each_entry(kvm, &vm_list, vm_list) {
+ stat_tmp.kvm = kvm;
+ vm_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
+ *val += tmp_val;
+ }
spin_unlock(&kvm_lock);
return 0;
}
@@ -3444,15 +3609,16 @@ static int vcpu_stat_get(void *_offset, u64 *val)
{
unsigned offset = (long)_offset;
struct kvm *kvm;
- struct kvm_vcpu *vcpu;
- int i;
+ struct kvm_stat_data stat_tmp = {.offset = offset};
+ u64 tmp_val;
*val = 0;
spin_lock(&kvm_lock);
- list_for_each_entry(kvm, &vm_list, vm_list)
- kvm_for_each_vcpu(i, vcpu, kvm)
- *val += *(u32 *)((void *)vcpu + offset);
-
+ list_for_each_entry(kvm, &vm_list, vm_list) {
+ stat_tmp.kvm = kvm;
+ vcpu_stat_get_per_vm((void *)&stat_tmp, &tmp_val);
+ *val += tmp_val;
+ }
spin_unlock(&kvm_lock);
return 0;
}
@@ -3473,7 +3639,8 @@ static int kvm_init_debug(void)
if (kvm_debugfs_dir == NULL)
goto out;
- for (p = debugfs_entries; p->name; ++p) {
+ kvm_debugfs_num_entries = 0;
+ for (p = debugfs_entries; p->name; ++p, kvm_debugfs_num_entries++) {
if (!debugfs_create_file(p->name, 0444, kvm_debugfs_dir,
(void *)(long)p->offset,
stat_fops[p->kind]))