KVM: Portability: split kvm_vcpu_ioctl

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@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Ehrhardt <ehrhardt@linux.vnet.ibm.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>

3 files changed, 234 insertions, 194 deletions

diff --git a/drivers/kvm/kvm.h b/drivers/kvm/kvm.h
index d56962d49aa..1edf8a5e365 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 ec696887b22..5fd2864b781 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 437902cf178..1fe209dd4ca 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];