[PATCH 37/50] KVM: Portability: split kvm_vcpu_ioctl

From: Avi Kivity
Date: Sun Dec 23 2007 - 10:01:51 EST


From: Carsten Otte <cotte@xxxxxxxxxx>

This patch splits kvm_vcpu_ioctl into archtecture independent parts, and
x86 specific parts which go to kvm_arch_vcpu_ioctl in x86.c.

Common ioctls for all architectures are:
KVM_RUN, KVM_GET/SET_(S-)REGS, KVM_TRANSLATE, KVM_INTERRUPT,
KVM_DEBUG_GUEST, KVM_SET_SIGNAL_MASK, KVM_GET/SET_FPU
Note that some PPC chips don't have an FPU, so we might need an #ifdef
around KVM_GET/SET_FPU one day.

x86 specific ioctls are:
KVM_GET/SET_LAPIC, KVM_SET_CPUID, KVM_GET/SET_MSRS

An interresting aspect is vcpu_load/vcpu_put. We now have a common
vcpu_load/put which does the preemption stuff, and an architecture
specific kvm_arch_vcpu_load/put. In the x86 case, this one calls the
vmx/svm function defined in kvm_x86_ops.

Signed-off-by: Carsten Otte <cotte@xxxxxxxxxx>
Reviewed-by: Christian Borntraeger <borntraeger@xxxxxxxxxx>
Reviewed-by: Christian Ehrhardt <ehrhardt@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Avi Kivity <avi@xxxxxxxxxxxx>
---
drivers/kvm/kvm.h | 9 ++
drivers/kvm/kvm_main.c | 200 ++------------------------------------------
drivers/kvm/x86.c | 219 ++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 234 insertions(+), 194 deletions(-)

diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index d56962d..1edf8a5 100644
--- a/drivers/kvm/kvm.h
+++ b/drivers/kvm/kvm.h
@@ -537,6 +537,10 @@ extern struct kvm_x86_ops *kvm_x86_ops;
int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id);
void kvm_vcpu_uninit(struct kvm_vcpu *vcpu);

+void vcpu_load(struct kvm_vcpu *vcpu);
+void vcpu_put(struct kvm_vcpu *vcpu);
+
+
int kvm_init_x86(struct kvm_x86_ops *ops, unsigned int vcpu_size,
struct module *module);
void kvm_exit_x86(void);
@@ -655,6 +659,11 @@ int kvm_fix_hypercall(struct kvm_vcpu *vcpu);

long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg);
+long kvm_arch_vcpu_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg);
+void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu);
+void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu);
+
__init void kvm_arch_init(void);

static inline void kvm_guest_enter(void)
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 9f7370f..03d6069 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -90,8 +90,6 @@ static struct kvm_stats_debugfs_item {

static struct dentry *debugfs_dir;

-#define MAX_IO_MSRS 256
-
#define CR0_RESERVED_BITS \
(~(unsigned long)(X86_CR0_PE | X86_CR0_MP | X86_CR0_EM | X86_CR0_TS \
| X86_CR0_ET | X86_CR0_NE | X86_CR0_WP | X86_CR0_AM \
@@ -179,21 +177,21 @@ EXPORT_SYMBOL_GPL(kvm_put_guest_fpu);
/*
* Switches to specified vcpu, until a matching vcpu_put()
*/
-static void vcpu_load(struct kvm_vcpu *vcpu)
+void vcpu_load(struct kvm_vcpu *vcpu)
{
int cpu;

mutex_lock(&vcpu->mutex);
cpu = get_cpu();
preempt_notifier_register(&vcpu->preempt_notifier);
- kvm_x86_ops->vcpu_load(vcpu, cpu);
+ kvm_arch_vcpu_load(vcpu, cpu);
put_cpu();
}

-static void vcpu_put(struct kvm_vcpu *vcpu)
+void vcpu_put(struct kvm_vcpu *vcpu)
{
preempt_disable();
- kvm_x86_ops->vcpu_put(vcpu);
+ kvm_arch_vcpu_put(vcpu);
preempt_notifier_unregister(&vcpu->preempt_notifier);
preempt_enable();
mutex_unlock(&vcpu->mutex);
@@ -2509,86 +2507,6 @@ void kvm_get_cs_db_l_bits(struct kvm_vcpu *vcpu, int *db, int *l)
EXPORT_SYMBOL_GPL(kvm_get_cs_db_l_bits);

/*
- * Adapt set_msr() to msr_io()'s calling convention
- */
-static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
-{
- return kvm_set_msr(vcpu, index, *data);
-}
-
-/*
- * Read or write a bunch of msrs. All parameters are kernel addresses.
- *
- * @return number of msrs set successfully.
- */
-static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs,
- struct kvm_msr_entry *entries,
- int (*do_msr)(struct kvm_vcpu *vcpu,
- unsigned index, u64 *data))
-{
- int i;
-
- vcpu_load(vcpu);
-
- for (i = 0; i < msrs->nmsrs; ++i)
- if (do_msr(vcpu, entries[i].index, &entries[i].data))
- break;
-
- vcpu_put(vcpu);
-
- return i;
-}
-
-/*
- * Read or write a bunch of msrs. Parameters are user addresses.
- *
- * @return number of msrs set successfully.
- */
-static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs,
- int (*do_msr)(struct kvm_vcpu *vcpu,
- unsigned index, u64 *data),
- int writeback)
-{
- struct kvm_msrs msrs;
- struct kvm_msr_entry *entries;
- int r, n;
- unsigned size;
-
- r = -EFAULT;
- if (copy_from_user(&msrs, user_msrs, sizeof msrs))
- goto out;
-
- r = -E2BIG;
- if (msrs.nmsrs >= MAX_IO_MSRS)
- goto out;
-
- r = -ENOMEM;
- size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
- entries = vmalloc(size);
- if (!entries)
- goto out;
-
- r = -EFAULT;
- if (copy_from_user(entries, user_msrs->entries, size))
- goto out_free;
-
- r = n = __msr_io(vcpu, &msrs, entries, do_msr);
- if (r < 0)
- goto out_free;
-
- r = -EFAULT;
- if (writeback && copy_to_user(user_msrs->entries, entries, size))
- goto out_free;
-
- r = n;
-
-out_free:
- vfree(entries);
-out:
- return r;
-}
-
-/*
* Translate a guest virtual address to a guest physical address.
*/
static int kvm_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
@@ -2761,48 +2679,6 @@ free_vcpu:
return r;
}

-static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
-{
- u64 efer;
- int i;
- struct kvm_cpuid_entry *e, *entry;
-
- rdmsrl(MSR_EFER, efer);
- entry = NULL;
- for (i = 0; i < vcpu->cpuid_nent; ++i) {
- e = &vcpu->cpuid_entries[i];
- if (e->function == 0x80000001) {
- entry = e;
- break;
- }
- }
- if (entry && (entry->edx & (1 << 20)) && !(efer & EFER_NX)) {
- entry->edx &= ~(1 << 20);
- printk(KERN_INFO "kvm: guest NX capability removed\n");
- }
-}
-
-static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
- struct kvm_cpuid *cpuid,
- struct kvm_cpuid_entry __user *entries)
-{
- int r;
-
- r = -E2BIG;
- if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
- goto out;
- r = -EFAULT;
- if (copy_from_user(&vcpu->cpuid_entries, entries,
- cpuid->nent * sizeof(struct kvm_cpuid_entry)))
- goto out;
- vcpu->cpuid_nent = cpuid->nent;
- cpuid_fix_nx_cap(vcpu);
- return 0;
-
-out:
- return r;
-}
-
static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
{
if (sigset) {
@@ -2875,33 +2751,12 @@ static int kvm_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu)
return 0;
}

-static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
- struct kvm_lapic_state *s)
-{
- vcpu_load(vcpu);
- memcpy(s->regs, vcpu->apic->regs, sizeof *s);
- vcpu_put(vcpu);
-
- return 0;
-}
-
-static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu,
- struct kvm_lapic_state *s)
-{
- vcpu_load(vcpu);
- memcpy(vcpu->apic->regs, s->regs, sizeof *s);
- kvm_apic_post_state_restore(vcpu);
- vcpu_put(vcpu);
-
- return 0;
-}
-
static long kvm_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
struct kvm_vcpu *vcpu = filp->private_data;
void __user *argp = (void __user *)arg;
- int r = -EINVAL;
+ int r;

switch (ioctl) {
case KVM_RUN:
@@ -2999,24 +2854,6 @@ static long kvm_vcpu_ioctl(struct file *filp,
r = 0;
break;
}
- case KVM_GET_MSRS:
- r = msr_io(vcpu, argp, kvm_get_msr, 1);
- break;
- case KVM_SET_MSRS:
- r = msr_io(vcpu, argp, do_set_msr, 0);
- break;
- case KVM_SET_CPUID: {
- struct kvm_cpuid __user *cpuid_arg = argp;
- struct kvm_cpuid cpuid;
-
- r = -EFAULT;
- if (copy_from_user(&cpuid, cpuid_arg, sizeof cpuid))
- goto out;
- r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries);
- if (r)
- goto out;
- break;
- }
case KVM_SET_SIGNAL_MASK: {
struct kvm_signal_mask __user *sigmask_arg = argp;
struct kvm_signal_mask kvm_sigmask;
@@ -3065,33 +2902,8 @@ static long kvm_vcpu_ioctl(struct file *filp,
r = 0;
break;
}
- case KVM_GET_LAPIC: {
- struct kvm_lapic_state lapic;
-
- memset(&lapic, 0, sizeof lapic);
- r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic);
- if (r)
- goto out;
- r = -EFAULT;
- if (copy_to_user(argp, &lapic, sizeof lapic))
- goto out;
- r = 0;
- break;
- }
- case KVM_SET_LAPIC: {
- struct kvm_lapic_state lapic;
-
- r = -EFAULT;
- if (copy_from_user(&lapic, argp, sizeof lapic))
- goto out;
- r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);;
- if (r)
- goto out;
- r = 0;
- break;
- }
default:
- ;
+ r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
}
out:
return r;
diff --git a/drivers/kvm/x86.c b/drivers/kvm/x86.c
index 437902c..1fe209d 100644
--- a/drivers/kvm/x86.c
+++ b/drivers/kvm/x86.c
@@ -14,10 +14,18 @@
*
*/

+#include "kvm.h"
#include "x86.h"
+#include "irq.h"
+
+#include <linux/kvm.h>
+#include <linux/fs.h>
+#include <linux/vmalloc.h>

#include <asm/uaccess.h>

+#define MAX_IO_MSRS 256
+
/*
* List of msr numbers which we expose to userspace through KVM_GET_MSRS
* and KVM_SET_MSRS, and KVM_GET_MSR_INDEX_LIST.
@@ -40,6 +48,86 @@ static u32 emulated_msrs[] = {
MSR_IA32_MISC_ENABLE,
};

+/*
+ * Adapt set_msr() to msr_io()'s calling convention
+ */
+static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
+{
+ return kvm_set_msr(vcpu, index, *data);
+}
+
+/*
+ * Read or write a bunch of msrs. All parameters are kernel addresses.
+ *
+ * @return number of msrs set successfully.
+ */
+static int __msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs *msrs,
+ struct kvm_msr_entry *entries,
+ int (*do_msr)(struct kvm_vcpu *vcpu,
+ unsigned index, u64 *data))
+{
+ int i;
+
+ vcpu_load(vcpu);
+
+ for (i = 0; i < msrs->nmsrs; ++i)
+ if (do_msr(vcpu, entries[i].index, &entries[i].data))
+ break;
+
+ vcpu_put(vcpu);
+
+ return i;
+}
+
+/*
+ * Read or write a bunch of msrs. Parameters are user addresses.
+ *
+ * @return number of msrs set successfully.
+ */
+static int msr_io(struct kvm_vcpu *vcpu, struct kvm_msrs __user *user_msrs,
+ int (*do_msr)(struct kvm_vcpu *vcpu,
+ unsigned index, u64 *data),
+ int writeback)
+{
+ struct kvm_msrs msrs;
+ struct kvm_msr_entry *entries;
+ int r, n;
+ unsigned size;
+
+ r = -EFAULT;
+ if (copy_from_user(&msrs, user_msrs, sizeof msrs))
+ goto out;
+
+ r = -E2BIG;
+ if (msrs.nmsrs >= MAX_IO_MSRS)
+ goto out;
+
+ r = -ENOMEM;
+ size = sizeof(struct kvm_msr_entry) * msrs.nmsrs;
+ entries = vmalloc(size);
+ if (!entries)
+ goto out;
+
+ r = -EFAULT;
+ if (copy_from_user(entries, user_msrs->entries, size))
+ goto out_free;
+
+ r = n = __msr_io(vcpu, &msrs, entries, do_msr);
+ if (r < 0)
+ goto out_free;
+
+ r = -EFAULT;
+ if (writeback && copy_to_user(user_msrs->entries, entries, size))
+ goto out_free;
+
+ r = n;
+
+out_free:
+ vfree(entries);
+out:
+ return r;
+}
+
long kvm_arch_dev_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -81,6 +169,137 @@ out:
return r;
}

+void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
+{
+ kvm_x86_ops->vcpu_load(vcpu, cpu);
+}
+
+void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
+{
+ kvm_x86_ops->vcpu_put(vcpu);
+}
+
+static void cpuid_fix_nx_cap(struct kvm_vcpu *vcpu)
+{
+ u64 efer;
+ int i;
+ struct kvm_cpuid_entry *e, *entry;
+
+ rdmsrl(MSR_EFER, efer);
+ entry = NULL;
+ for (i = 0; i < vcpu->cpuid_nent; ++i) {
+ e = &vcpu->cpuid_entries[i];
+ if (e->function == 0x80000001) {
+ entry = e;
+ break;
+ }
+ }
+ if (entry && (entry->edx & (1 << 20)) && !(efer & EFER_NX)) {
+ entry->edx &= ~(1 << 20);
+ printk(KERN_INFO "kvm: guest NX capability removed\n");
+ }
+}
+
+static int kvm_vcpu_ioctl_set_cpuid(struct kvm_vcpu *vcpu,
+ struct kvm_cpuid *cpuid,
+ struct kvm_cpuid_entry __user *entries)
+{
+ int r;
+
+ r = -E2BIG;
+ if (cpuid->nent > KVM_MAX_CPUID_ENTRIES)
+ goto out;
+ r = -EFAULT;
+ if (copy_from_user(&vcpu->cpuid_entries, entries,
+ cpuid->nent * sizeof(struct kvm_cpuid_entry)))
+ goto out;
+ vcpu->cpuid_nent = cpuid->nent;
+ cpuid_fix_nx_cap(vcpu);
+ return 0;
+
+out:
+ return r;
+}
+
+static int kvm_vcpu_ioctl_get_lapic(struct kvm_vcpu *vcpu,
+ struct kvm_lapic_state *s)
+{
+ vcpu_load(vcpu);
+ memcpy(s->regs, vcpu->apic->regs, sizeof *s);
+ vcpu_put(vcpu);
+
+ return 0;
+}
+
+static int kvm_vcpu_ioctl_set_lapic(struct kvm_vcpu *vcpu,
+ struct kvm_lapic_state *s)
+{
+ vcpu_load(vcpu);
+ memcpy(vcpu->apic->regs, s->regs, sizeof *s);
+ kvm_apic_post_state_restore(vcpu);
+ vcpu_put(vcpu);
+
+ return 0;
+}
+
+long kvm_arch_vcpu_ioctl(struct file *filp,
+ unsigned int ioctl, unsigned long arg)
+{
+ struct kvm_vcpu *vcpu = filp->private_data;
+ void __user *argp = (void __user *)arg;
+ int r;
+
+ switch (ioctl) {
+ case KVM_GET_LAPIC: {
+ struct kvm_lapic_state lapic;
+
+ memset(&lapic, 0, sizeof lapic);
+ r = kvm_vcpu_ioctl_get_lapic(vcpu, &lapic);
+ if (r)
+ goto out;
+ r = -EFAULT;
+ if (copy_to_user(argp, &lapic, sizeof lapic))
+ goto out;
+ r = 0;
+ break;
+ }
+ case KVM_SET_LAPIC: {
+ struct kvm_lapic_state lapic;
+
+ r = -EFAULT;
+ if (copy_from_user(&lapic, argp, sizeof lapic))
+ goto out;
+ r = kvm_vcpu_ioctl_set_lapic(vcpu, &lapic);;
+ if (r)
+ goto out;
+ r = 0;
+ break;
+ }
+ case KVM_SET_CPUID: {
+ struct kvm_cpuid __user *cpuid_arg = argp;
+ struct kvm_cpuid cpuid;
+
+ r = -EFAULT;
+ if (copy_from_user(&cpuid, cpuid_arg, sizeof cpuid))
+ goto out;
+ r = kvm_vcpu_ioctl_set_cpuid(vcpu, &cpuid, cpuid_arg->entries);
+ if (r)
+ goto out;
+ break;
+ }
+ case KVM_GET_MSRS:
+ r = msr_io(vcpu, argp, kvm_get_msr, 1);
+ break;
+ case KVM_SET_MSRS:
+ r = msr_io(vcpu, argp, do_set_msr, 0);
+ break;
+ default:
+ r = -EINVAL;
+ }
+out:
+ return r;
+}
+
static __init void kvm_init_msr_list(void)
{
u32 dummy[2];
--
1.5.3.7

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