1 files changed, 149 insertions, 114 deletions

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 6fb36c80e3e8..a593d092d85b 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -96,6 +96,9 @@ struct segment_descriptor_64 {
 
 #endif
 
+static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
+			   unsigned long arg);
+
 static struct inode *kvmfs_inode(struct file_operations *fops)
 {
 	int error = -ENOMEM;
@@ -246,24 +249,30 @@ int kvm_write_guest(struct kvm_vcpu *vcpu, gva_t addr, unsigned long size,
 }
 EXPORT_SYMBOL_GPL(kvm_write_guest);
 
-static int vcpu_slot(struct kvm_vcpu *vcpu)
+/*
+ * Switches to specified vcpu, until a matching vcpu_put()
+ */
+static void vcpu_load(struct kvm_vcpu *vcpu)
 {
-	return vcpu - vcpu->kvm->vcpus;
+	mutex_lock(&vcpu->mutex);
+	kvm_arch_ops->vcpu_load(vcpu);
 }
 
 /*
- * Switches to specified vcpu, until a matching vcpu_put()
+ * Switches to specified vcpu, until a matching vcpu_put(). Will return NULL
+ * if the slot is not populated.
  */
-static struct kvm_vcpu *vcpu_load(struct kvm *kvm, int vcpu_slot)
+static struct kvm_vcpu *vcpu_load_slot(struct kvm *kvm, int slot)
 {
-	struct kvm_vcpu *vcpu = &kvm->vcpus[vcpu_slot];
+	struct kvm_vcpu *vcpu = &kvm->vcpus[slot];
 
 	mutex_lock(&vcpu->mutex);
-	if (unlikely(!vcpu->vmcs)) {
+	if (!vcpu->vmcs) {
 		mutex_unlock(&vcpu->mutex);
 		return NULL;
 	}
-	return kvm_arch_ops->vcpu_load(vcpu);
+	kvm_arch_ops->vcpu_load(vcpu);
+	return vcpu;
 }
 
 static void vcpu_put(struct kvm_vcpu *vcpu)
@@ -336,9 +345,10 @@ static void kvm_free_physmem(struct kvm *kvm)
 
 static void kvm_free_vcpu(struct kvm_vcpu *vcpu)
 {
-	if (!vcpu_load(vcpu->kvm, vcpu_slot(vcpu)))
+	if (!vcpu->vmcs)
 		return;
 
+	vcpu_load(vcpu);
 	kvm_mmu_destroy(vcpu);
 	vcpu_put(vcpu);
 	kvm_arch_ops->vcpu_free(vcpu);
@@ -725,7 +735,7 @@ raced:
 	for (i = 0; i < KVM_MAX_VCPUS; ++i) {
 		struct kvm_vcpu *vcpu;
 
-		vcpu = vcpu_load(kvm, i);
+		vcpu = vcpu_load_slot(kvm, i);
 		if (!vcpu)
 			continue;
 		kvm_mmu_reset_context(vcpu);
@@ -791,8 +801,9 @@ static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
 	if (any) {
 		cleared = 0;
 		for (i = 0; i < KVM_MAX_VCPUS; ++i) {
-			struct kvm_vcpu *vcpu = vcpu_load(kvm, i);
+			struct kvm_vcpu *vcpu;
 
+			vcpu = vcpu_load_slot(kvm, i);
 			if (!vcpu)
 				continue;
 			if (!cleared) {
@@ -1461,8 +1472,7 @@ void kvm_resched(struct kvm_vcpu *vcpu)
 {
 	vcpu_put(vcpu);
 	cond_resched();
-	/* Cannot fail -  no vcpu unplug yet. */
-	vcpu_load(vcpu->kvm, vcpu_slot(vcpu));
+	vcpu_load(vcpu);
 }
 EXPORT_SYMBOL_GPL(kvm_resched);
 
@@ -1484,17 +1494,11 @@ void save_msrs(struct vmx_msr_entry *e, int n)
 }
 EXPORT_SYMBOL_GPL(save_msrs);
 
-static int kvm_vm_ioctl_run(struct kvm *kvm, struct kvm_run *kvm_run)
+static int kvm_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 {
-	struct kvm_vcpu *vcpu;
 	int r;
 
-	if (!valid_vcpu(kvm_run->vcpu))
-		return -EINVAL;
-
-	vcpu = vcpu_load(kvm, kvm_run->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	/* re-sync apic's tpr */
 	vcpu->cr8 = kvm_run->cr8;
@@ -1517,16 +1521,10 @@ static int kvm_vm_ioctl_run(struct kvm *kvm, struct kvm_run *kvm_run)
 	return r;
 }
 
-static int kvm_vm_ioctl_get_regs(struct kvm *kvm, struct kvm_regs *regs)
+static int kvm_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu,
+				   struct kvm_regs *regs)
 {
-	struct kvm_vcpu *vcpu;
-
-	if (!valid_vcpu(regs->vcpu))
-		return -EINVAL;
-
-	vcpu = vcpu_load(kvm, regs->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	kvm_arch_ops->cache_regs(vcpu);
 
@@ -1563,16 +1561,10 @@ static int kvm_vm_ioctl_get_regs(struct kvm *kvm, struct kvm_regs *regs)
 	return 0;
 }
 
-static int kvm_vm_ioctl_set_regs(struct kvm *kvm, struct kvm_regs *regs)
+static int kvm_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu,
+				   struct kvm_regs *regs)
 {
-	struct kvm_vcpu *vcpu;
-
-	if (!valid_vcpu(regs->vcpu))
-		return -EINVAL;
-
-	vcpu = vcpu_load(kvm, regs->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	vcpu->regs[VCPU_REGS_RAX] = regs->rax;
 	vcpu->regs[VCPU_REGS_RBX] = regs->rbx;
@@ -1609,16 +1601,12 @@ static void get_segment(struct kvm_vcpu *vcpu,
 	return kvm_arch_ops->get_segment(vcpu, var, seg);
 }
 
-static int kvm_vm_ioctl_get_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
+static int kvm_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu,
+				    struct kvm_sregs *sregs)
 {
-	struct kvm_vcpu *vcpu;
 	struct descriptor_table dt;
 
-	if (!valid_vcpu(sregs->vcpu))
-		return -EINVAL;
-	vcpu = vcpu_load(kvm, sregs->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	get_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
 	get_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
@@ -1660,18 +1648,14 @@ static void set_segment(struct kvm_vcpu *vcpu,
 	return kvm_arch_ops->set_segment(vcpu, var, seg);
 }
 
-static int kvm_vm_ioctl_set_sregs(struct kvm *kvm, struct kvm_sregs *sregs)
+static int kvm_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu,
+				    struct kvm_sregs *sregs)
 {
-	struct kvm_vcpu *vcpu;
 	int mmu_reset_needed = 0;
 	int i;
 	struct descriptor_table dt;
 
-	if (!valid_vcpu(sregs->vcpu))
-		return -EINVAL;
-	vcpu = vcpu_load(kvm, sregs->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	set_segment(vcpu, &sregs->cs, VCPU_SREG_CS);
 	set_segment(vcpu, &sregs->ds, VCPU_SREG_DS);
@@ -1777,20 +1761,14 @@ static int do_set_msr(struct kvm_vcpu *vcpu, unsigned index, u64 *data)
  *
  * @return number of msrs set successfully.
  */
-static int __msr_io(struct kvm *kvm, struct kvm_msrs *msrs,
+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))
 {
-	struct kvm_vcpu *vcpu;
 	int i;
 
-	if (!valid_vcpu(msrs->vcpu))
-		return -EINVAL;
-
-	vcpu = vcpu_load(kvm, msrs->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	for (i = 0; i < msrs->nmsrs; ++i)
 		if (do_msr(vcpu, entries[i].index, &entries[i].data))
@@ -1806,7 +1784,7 @@ static int __msr_io(struct kvm *kvm, struct kvm_msrs *msrs,
  *
  * @return number of msrs set successfully.
  */
-static int msr_io(struct kvm *kvm, struct kvm_msrs __user *user_msrs,
+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)
@@ -1834,7 +1812,7 @@ static int msr_io(struct kvm *kvm, struct kvm_msrs __user *user_msrs,
 	if (copy_from_user(entries, user_msrs->entries, size))
 		goto out_free;
 
-	r = n = __msr_io(kvm, &msrs, entries, do_msr);
+	r = n = __msr_io(vcpu, &msrs, entries, do_msr);
 	if (r < 0)
 		goto out_free;
 
@@ -1853,38 +1831,31 @@ out:
 /*
  * Translate a guest virtual address to a guest physical address.
  */
-static int kvm_vm_ioctl_translate(struct kvm *kvm, struct kvm_translation *tr)
+static int kvm_vcpu_ioctl_translate(struct kvm_vcpu *vcpu,
+				    struct kvm_translation *tr)
 {
 	unsigned long vaddr = tr->linear_address;
-	struct kvm_vcpu *vcpu;
 	gpa_t gpa;
 
-	vcpu = vcpu_load(kvm, tr->vcpu);
-	if (!vcpu)
-		return -ENOENT;
-	spin_lock(&kvm->lock);
+	vcpu_load(vcpu);
+	spin_lock(&vcpu->kvm->lock);
 	gpa = vcpu->mmu.gva_to_gpa(vcpu, vaddr);
 	tr->physical_address = gpa;
 	tr->valid = gpa != UNMAPPED_GVA;
 	tr->writeable = 1;
 	tr->usermode = 0;
-	spin_unlock(&kvm->lock);
+	spin_unlock(&vcpu->kvm->lock);
 	vcpu_put(vcpu);
 
 	return 0;
 }
 
-static int kvm_vm_ioctl_interrupt(struct kvm *kvm, struct kvm_interrupt *irq)
+static int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
+				    struct kvm_interrupt *irq)
 {
-	struct kvm_vcpu *vcpu;
-
-	if (!valid_vcpu(irq->vcpu))
-		return -EINVAL;
 	if (irq->irq < 0 || irq->irq >= 256)
 		return -EINVAL;
-	vcpu = vcpu_load(kvm, irq->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	set_bit(irq->irq, vcpu->irq_pending);
 	set_bit(irq->irq / BITS_PER_LONG, &vcpu->irq_summary);
@@ -1894,17 +1865,12 @@ static int kvm_vm_ioctl_interrupt(struct kvm *kvm, struct kvm_interrupt *irq)
 	return 0;
 }
 
-static int kvm_vm_ioctl_debug_guest(struct kvm *kvm,
-				     struct kvm_debug_guest *dbg)
+static int kvm_vcpu_ioctl_debug_guest(struct kvm_vcpu *vcpu,
+				      struct kvm_debug_guest *dbg)
 {
-	struct kvm_vcpu *vcpu;
 	int r;
 
-	if (!valid_vcpu(dbg->vcpu))
-		return -EINVAL;
-	vcpu = vcpu_load(kvm, dbg->vcpu);
-	if (!vcpu)
-		return -ENOENT;
+	vcpu_load(vcpu);
 
 	r = kvm_arch_ops->set_guest_debug(vcpu, dbg);
 
@@ -1913,6 +1879,59 @@ static int kvm_vm_ioctl_debug_guest(struct kvm *kvm,
 	return r;
 }
 
+static int kvm_vcpu_release(struct inode *inode, struct file *filp)
+{
+	struct kvm_vcpu *vcpu = filp->private_data;
+
+	fput(vcpu->kvm->filp);
+	return 0;
+}
+
+static struct file_operations kvm_vcpu_fops = {
+	.release        = kvm_vcpu_release,
+	.unlocked_ioctl = kvm_vcpu_ioctl,
+	.compat_ioctl   = kvm_vcpu_ioctl,
+};
+
+/*
+ * Allocates an inode for the vcpu.
+ */
+static int create_vcpu_fd(struct kvm_vcpu *vcpu)
+{
+	int fd, r;
+	struct inode *inode;
+	struct file *file;
+
+	atomic_inc(&vcpu->kvm->filp->f_count);
+	inode = kvmfs_inode(&kvm_vcpu_fops);
+	if (IS_ERR(inode)) {
+		r = PTR_ERR(inode);
+		goto out1;
+	}
+
+	file = kvmfs_file(inode, vcpu);
+	if (IS_ERR(file)) {
+		r = PTR_ERR(file);
+		goto out2;
+	}
+
+	r = get_unused_fd();
+	if (r < 0)
+		goto out3;
+	fd = r;
+	fd_install(fd, file);
+
+	return fd;
+
+out3:
+	fput(file);
+out2:
+	iput(inode);
+out1:
+	fput(vcpu->kvm->filp);
+	return r;
+}
+
 /*
  * Creates some virtual cpus.  Good luck creating more than one.
  */
@@ -1955,7 +1974,11 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, int n)
 	if (r < 0)
 		goto out_free_vcpus;
 
-	return 0;
+	r = create_vcpu_fd(vcpu);
+	if (r < 0)
+		goto out_free_vcpus;
+
+	return r;
 
 out_free_vcpus:
 	kvm_free_vcpu(vcpu);
@@ -1964,26 +1987,21 @@ out:
 	return r;
 }
 
-static long kvm_vm_ioctl(struct file *filp,
-			 unsigned int ioctl, unsigned long arg)
+static long kvm_vcpu_ioctl(struct file *filp,
+			   unsigned int ioctl, unsigned long arg)
 {
-	struct kvm *kvm = filp->private_data;
+	struct kvm_vcpu *vcpu = filp->private_data;
 	void __user *argp = (void __user *)arg;
 	int r = -EINVAL;
 
 	switch (ioctl) {
-	case KVM_CREATE_VCPU:
-		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
-		if (r)
-			goto out;
-		break;
 	case KVM_RUN: {
 		struct kvm_run kvm_run;
 
 		r = -EFAULT;
 		if (copy_from_user(&kvm_run, argp, sizeof kvm_run))
 			goto out;
-		r = kvm_vm_ioctl_run(kvm, &kvm_run);
+		r = kvm_vcpu_ioctl_run(vcpu, &kvm_run);
 		if (r < 0 &&  r != -EINTR)
 			goto out;
 		if (copy_to_user(argp, &kvm_run, sizeof kvm_run)) {
@@ -1995,10 +2013,8 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_GET_REGS: {
 		struct kvm_regs kvm_regs;
 
-		r = -EFAULT;
-		if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
-			goto out;
-		r = kvm_vm_ioctl_get_regs(kvm, &kvm_regs);
+		memset(&kvm_regs, 0, sizeof kvm_regs);
+		r = kvm_vcpu_ioctl_get_regs(vcpu, &kvm_regs);
 		if (r)
 			goto out;
 		r = -EFAULT;
@@ -2013,7 +2029,7 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = -EFAULT;
 		if (copy_from_user(&kvm_regs, argp, sizeof kvm_regs))
 			goto out;
-		r = kvm_vm_ioctl_set_regs(kvm, &kvm_regs);
+		r = kvm_vcpu_ioctl_set_regs(vcpu, &kvm_regs);
 		if (r)
 			goto out;
 		r = 0;
@@ -2022,10 +2038,8 @@ static long kvm_vm_ioctl(struct file *filp,
 	case KVM_GET_SREGS: {
 		struct kvm_sregs kvm_sregs;
 
-		r = -EFAULT;
-		if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
-			goto out;
-		r = kvm_vm_ioctl_get_sregs(kvm, &kvm_sregs);
+		memset(&kvm_sregs, 0, sizeof kvm_sregs);
+		r = kvm_vcpu_ioctl_get_sregs(vcpu, &kvm_sregs);
 		if (r)
 			goto out;
 		r = -EFAULT;
@@ -2040,7 +2054,7 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = -EFAULT;
 		if (copy_from_user(&kvm_sregs, argp, sizeof kvm_sregs))
 			goto out;
-		r = kvm_vm_ioctl_set_sregs(kvm, &kvm_sregs);
+		r = kvm_vcpu_ioctl_set_sregs(vcpu, &kvm_sregs);
 		if (r)
 			goto out;
 		r = 0;
@@ -2052,7 +2066,7 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = -EFAULT;
 		if (copy_from_user(&tr, argp, sizeof tr))
 			goto out;
-		r = kvm_vm_ioctl_translate(kvm, &tr);
+		r = kvm_vcpu_ioctl_translate(vcpu, &tr);
 		if (r)
 			goto out;
 		r = -EFAULT;
@@ -2067,7 +2081,7 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = -EFAULT;
 		if (copy_from_user(&irq, argp, sizeof irq))
 			goto out;
-		r = kvm_vm_ioctl_interrupt(kvm, &irq);
+		r = kvm_vcpu_ioctl_interrupt(vcpu, &irq);
 		if (r)
 			goto out;
 		r = 0;
@@ -2079,12 +2093,38 @@ static long kvm_vm_ioctl(struct file *filp,
 		r = -EFAULT;
 		if (copy_from_user(&dbg, argp, sizeof dbg))
 			goto out;
-		r = kvm_vm_ioctl_debug_guest(kvm, &dbg);
+		r = kvm_vcpu_ioctl_debug_guest(vcpu, &dbg);
 		if (r)
 			goto out;
 		r = 0;
 		break;
 	}
+	case KVM_GET_MSRS:
+		r = msr_io(vcpu, argp, get_msr, 1);
+		break;
+	case KVM_SET_MSRS:
+		r = msr_io(vcpu, argp, do_set_msr, 0);
+		break;
+	default:
+		;
+	}
+out:
+	return r;
+}
+
+static long kvm_vm_ioctl(struct file *filp,
+			   unsigned int ioctl, unsigned long arg)
+{
+	struct kvm *kvm = filp->private_data;
+	void __user *argp = (void __user *)arg;
+	int r = -EINVAL;
+
+	switch (ioctl) {
+	case KVM_CREATE_VCPU:
+		r = kvm_vm_ioctl_create_vcpu(kvm, arg);
+		if (r < 0)
+			goto out;
+		break;
 	case KVM_SET_MEMORY_REGION: {
 		struct kvm_memory_region kvm_mem;
 
@@ -2107,12 +2147,6 @@ static long kvm_vm_ioctl(struct file *filp,
 			goto out;
 		break;
 	}
-	case KVM_GET_MSRS:
-		r = msr_io(kvm, argp, get_msr, 1);
-		break;
-	case KVM_SET_MSRS:
-		r = msr_io(kvm, argp, do_set_msr, 0);
-		break;
 	default:
 		;
 	}
@@ -2182,6 +2216,7 @@ static int kvm_dev_ioctl_create_vm(void)
 		r = PTR_ERR(file);
 		goto out3;
 	}
+	kvm->filp = file;
 
 	r = get_unused_fd();
 	if (r < 0)