summaryrefslogtreecommitdiffstats
path: root/arch/x86/kvm/xen.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/x86/kvm/xen.c')
-rw-r--r--arch/x86/kvm/xen.c144
1 files changed, 75 insertions, 69 deletions
diff --git a/arch/x86/kvm/xen.c b/arch/x86/kvm/xen.c
index d7af40240248..2e29bdc2949c 100644
--- a/arch/x86/kvm/xen.c
+++ b/arch/x86/kvm/xen.c
@@ -41,7 +41,7 @@ static int kvm_xen_shared_info_init(struct kvm *kvm, gfn_t gfn)
int ret = 0;
int idx = srcu_read_lock(&kvm->srcu);
- if (gfn == GPA_INVALID) {
+ if (gfn == KVM_XEN_INVALID_GFN) {
kvm_gpc_deactivate(gpc);
goto out;
}
@@ -659,7 +659,7 @@ int kvm_xen_hvm_get_attr(struct kvm *kvm, struct kvm_xen_hvm_attr *data)
if (kvm->arch.xen.shinfo_cache.active)
data->u.shared_info.gfn = gpa_to_gfn(kvm->arch.xen.shinfo_cache.gpa);
else
- data->u.shared_info.gfn = GPA_INVALID;
+ data->u.shared_info.gfn = KVM_XEN_INVALID_GFN;
r = 0;
break;
@@ -705,7 +705,7 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
BUILD_BUG_ON(offsetof(struct vcpu_info, time) !=
offsetof(struct compat_vcpu_info, time));
- if (data->u.gpa == GPA_INVALID) {
+ if (data->u.gpa == KVM_XEN_INVALID_GPA) {
kvm_gpc_deactivate(&vcpu->arch.xen.vcpu_info_cache);
r = 0;
break;
@@ -719,7 +719,7 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
break;
case KVM_XEN_VCPU_ATTR_TYPE_VCPU_TIME_INFO:
- if (data->u.gpa == GPA_INVALID) {
+ if (data->u.gpa == KVM_XEN_INVALID_GPA) {
kvm_gpc_deactivate(&vcpu->arch.xen.vcpu_time_info_cache);
r = 0;
break;
@@ -739,7 +739,7 @@ int kvm_xen_vcpu_set_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
r = -EOPNOTSUPP;
break;
}
- if (data->u.gpa == GPA_INVALID) {
+ if (data->u.gpa == KVM_XEN_INVALID_GPA) {
r = 0;
deactivate_out:
kvm_gpc_deactivate(&vcpu->arch.xen.runstate_cache);
@@ -937,7 +937,7 @@ int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
if (vcpu->arch.xen.vcpu_info_cache.active)
data->u.gpa = vcpu->arch.xen.vcpu_info_cache.gpa;
else
- data->u.gpa = GPA_INVALID;
+ data->u.gpa = KVM_XEN_INVALID_GPA;
r = 0;
break;
@@ -945,7 +945,7 @@ int kvm_xen_vcpu_get_attr(struct kvm_vcpu *vcpu, struct kvm_xen_vcpu_attr *data)
if (vcpu->arch.xen.vcpu_time_info_cache.active)
data->u.gpa = vcpu->arch.xen.vcpu_time_info_cache.gpa;
else
- data->u.gpa = GPA_INVALID;
+ data->u.gpa = KVM_XEN_INVALID_GPA;
r = 0;
break;
@@ -1069,6 +1069,7 @@ int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data)
u8 blob_size = lm ? kvm->arch.xen_hvm_config.blob_size_64
: kvm->arch.xen_hvm_config.blob_size_32;
u8 *page;
+ int ret;
if (page_num >= blob_size)
return 1;
@@ -1079,10 +1080,10 @@ int kvm_xen_write_hypercall_page(struct kvm_vcpu *vcpu, u64 data)
if (IS_ERR(page))
return PTR_ERR(page);
- if (kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE)) {
- kfree(page);
+ ret = kvm_vcpu_write_guest(vcpu, page_addr, page, PAGE_SIZE);
+ kfree(page);
+ if (ret)
return 1;
- }
}
return 0;
}
@@ -1183,30 +1184,22 @@ static bool wait_pending_event(struct kvm_vcpu *vcpu, int nr_ports,
static bool kvm_xen_schedop_poll(struct kvm_vcpu *vcpu, bool longmode,
u64 param, u64 *r)
{
- int idx, i;
struct sched_poll sched_poll;
evtchn_port_t port, *ports;
- gpa_t gpa;
+ struct x86_exception e;
+ int i;
if (!lapic_in_kernel(vcpu) ||
!(vcpu->kvm->arch.xen_hvm_config.flags & KVM_XEN_HVM_CONFIG_EVTCHN_SEND))
return false;
- idx = srcu_read_lock(&vcpu->kvm->srcu);
- gpa = kvm_mmu_gva_to_gpa_system(vcpu, param, NULL);
- srcu_read_unlock(&vcpu->kvm->srcu, idx);
- if (!gpa) {
- *r = -EFAULT;
- return true;
- }
-
if (IS_ENABLED(CONFIG_64BIT) && !longmode) {
struct compat_sched_poll sp32;
/* Sanity check that the compat struct definition is correct */
BUILD_BUG_ON(sizeof(sp32) != 16);
- if (kvm_vcpu_read_guest(vcpu, gpa, &sp32, sizeof(sp32))) {
+ if (kvm_read_guest_virt(vcpu, param, &sp32, sizeof(sp32), &e)) {
*r = -EFAULT;
return true;
}
@@ -1220,8 +1213,8 @@ static bool kvm_xen_schedop_poll(struct kvm_vcpu *vcpu, bool longmode,
sched_poll.nr_ports = sp32.nr_ports;
sched_poll.timeout = sp32.timeout;
} else {
- if (kvm_vcpu_read_guest(vcpu, gpa, &sched_poll,
- sizeof(sched_poll))) {
+ if (kvm_read_guest_virt(vcpu, param, &sched_poll,
+ sizeof(sched_poll), &e)) {
*r = -EFAULT;
return true;
}
@@ -1243,18 +1236,13 @@ static bool kvm_xen_schedop_poll(struct kvm_vcpu *vcpu, bool longmode,
} else
ports = &port;
+ if (kvm_read_guest_virt(vcpu, (gva_t)sched_poll.ports, ports,
+ sched_poll.nr_ports * sizeof(*ports), &e)) {
+ *r = -EFAULT;
+ return true;
+ }
+
for (i = 0; i < sched_poll.nr_ports; i++) {
- idx = srcu_read_lock(&vcpu->kvm->srcu);
- gpa = kvm_mmu_gva_to_gpa_system(vcpu,
- (gva_t)(sched_poll.ports + i),
- NULL);
- srcu_read_unlock(&vcpu->kvm->srcu, idx);
-
- if (!gpa || kvm_vcpu_read_guest(vcpu, gpa,
- &ports[i], sizeof(port))) {
- *r = -EFAULT;
- goto out;
- }
if (ports[i] >= max_evtchn_port(vcpu->kvm)) {
*r = -EINVAL;
goto out;
@@ -1330,9 +1318,8 @@ static bool kvm_xen_hcall_vcpu_op(struct kvm_vcpu *vcpu, bool longmode, int cmd,
int vcpu_id, u64 param, u64 *r)
{
struct vcpu_set_singleshot_timer oneshot;
+ struct x86_exception e;
s64 delta;
- gpa_t gpa;
- int idx;
if (!kvm_xen_timer_enabled(vcpu))
return false;
@@ -1343,9 +1330,6 @@ static bool kvm_xen_hcall_vcpu_op(struct kvm_vcpu *vcpu, bool longmode, int cmd,
*r = -EINVAL;
return true;
}
- idx = srcu_read_lock(&vcpu->kvm->srcu);
- gpa = kvm_mmu_gva_to_gpa_system(vcpu, param, NULL);
- srcu_read_unlock(&vcpu->kvm->srcu, idx);
/*
* The only difference for 32-bit compat is the 4 bytes of
@@ -1363,9 +1347,8 @@ static bool kvm_xen_hcall_vcpu_op(struct kvm_vcpu *vcpu, bool longmode, int cmd,
BUILD_BUG_ON(sizeof_field(struct compat_vcpu_set_singleshot_timer, flags) !=
sizeof_field(struct vcpu_set_singleshot_timer, flags));
- if (!gpa ||
- kvm_vcpu_read_guest(vcpu, gpa, &oneshot, longmode ? sizeof(oneshot) :
- sizeof(struct compat_vcpu_set_singleshot_timer))) {
+ if (kvm_read_guest_virt(vcpu, param, &oneshot, longmode ? sizeof(oneshot) :
+ sizeof(struct compat_vcpu_set_singleshot_timer), &e)) {
*r = -EFAULT;
return true;
}
@@ -1825,20 +1808,20 @@ static int kvm_xen_eventfd_update(struct kvm *kvm,
{
u32 port = data->u.evtchn.send_port;
struct evtchnfd *evtchnfd;
+ int ret;
- if (!port || port >= max_evtchn_port(kvm))
- return -EINVAL;
-
+ /* Protect writes to evtchnfd as well as the idr lookup. */
mutex_lock(&kvm->lock);
evtchnfd = idr_find(&kvm->arch.xen.evtchn_ports, port);
- mutex_unlock(&kvm->lock);
+ ret = -ENOENT;
if (!evtchnfd)
- return -ENOENT;
+ goto out_unlock;
/* For an UPDATE, nothing may change except the priority/vcpu */
+ ret = -EINVAL;
if (evtchnfd->type != data->u.evtchn.type)
- return -EINVAL;
+ goto out_unlock;
/*
* Port cannot change, and if it's zero that was an eventfd
@@ -1846,20 +1829,21 @@ static int kvm_xen_eventfd_update(struct kvm *kvm,
*/
if (!evtchnfd->deliver.port.port ||
evtchnfd->deliver.port.port != data->u.evtchn.deliver.port.port)
- return -EINVAL;
+ goto out_unlock;
/* We only support 2 level event channels for now */
if (data->u.evtchn.deliver.port.priority != KVM_IRQ_ROUTING_XEN_EVTCHN_PRIO_2LEVEL)
- return -EINVAL;
+ goto out_unlock;
- mutex_lock(&kvm->lock);
evtchnfd->deliver.port.priority = data->u.evtchn.deliver.port.priority;
if (evtchnfd->deliver.port.vcpu_id != data->u.evtchn.deliver.port.vcpu) {
evtchnfd->deliver.port.vcpu_id = data->u.evtchn.deliver.port.vcpu;
evtchnfd->deliver.port.vcpu_idx = -1;
}
+ ret = 0;
+out_unlock:
mutex_unlock(&kvm->lock);
- return 0;
+ return ret;
}
/*
@@ -1871,12 +1855,9 @@ static int kvm_xen_eventfd_assign(struct kvm *kvm,
{
u32 port = data->u.evtchn.send_port;
struct eventfd_ctx *eventfd = NULL;
- struct evtchnfd *evtchnfd = NULL;
+ struct evtchnfd *evtchnfd;
int ret = -EINVAL;
- if (!port || port >= max_evtchn_port(kvm))
- return -EINVAL;
-
evtchnfd = kzalloc(sizeof(struct evtchnfd), GFP_KERNEL);
if (!evtchnfd)
return -ENOMEM;
@@ -1952,8 +1933,7 @@ static int kvm_xen_eventfd_deassign(struct kvm *kvm, u32 port)
if (!evtchnfd)
return -ENOENT;
- if (kvm)
- synchronize_srcu(&kvm->srcu);
+ synchronize_srcu(&kvm->srcu);
if (!evtchnfd->deliver.port.port)
eventfd_ctx_put(evtchnfd->deliver.eventfd.ctx);
kfree(evtchnfd);
@@ -1962,18 +1942,42 @@ static int kvm_xen_eventfd_deassign(struct kvm *kvm, u32 port)
static int kvm_xen_eventfd_reset(struct kvm *kvm)
{
- struct evtchnfd *evtchnfd;
+ struct evtchnfd *evtchnfd, **all_evtchnfds;
int i;
+ int n = 0;
mutex_lock(&kvm->lock);
+
+ /*
+ * Because synchronize_srcu() cannot be called inside the
+ * critical section, first collect all the evtchnfd objects
+ * in an array as they are removed from evtchn_ports.
+ */
+ idr_for_each_entry(&kvm->arch.xen.evtchn_ports, evtchnfd, i)
+ n++;
+
+ all_evtchnfds = kmalloc_array(n, sizeof(struct evtchnfd *), GFP_KERNEL);
+ if (!all_evtchnfds) {
+ mutex_unlock(&kvm->lock);
+ return -ENOMEM;
+ }
+
+ n = 0;
idr_for_each_entry(&kvm->arch.xen.evtchn_ports, evtchnfd, i) {
+ all_evtchnfds[n++] = evtchnfd;
idr_remove(&kvm->arch.xen.evtchn_ports, evtchnfd->send_port);
- synchronize_srcu(&kvm->srcu);
+ }
+ mutex_unlock(&kvm->lock);
+
+ synchronize_srcu(&kvm->srcu);
+
+ while (n--) {
+ evtchnfd = all_evtchnfds[n];
if (!evtchnfd->deliver.port.port)
eventfd_ctx_put(evtchnfd->deliver.eventfd.ctx);
kfree(evtchnfd);
}
- mutex_unlock(&kvm->lock);
+ kfree(all_evtchnfds);
return 0;
}
@@ -2002,20 +2006,22 @@ static bool kvm_xen_hcall_evtchn_send(struct kvm_vcpu *vcpu, u64 param, u64 *r)
{
struct evtchnfd *evtchnfd;
struct evtchn_send send;
- gpa_t gpa;
- int idx;
-
- idx = srcu_read_lock(&vcpu->kvm->srcu);
- gpa = kvm_mmu_gva_to_gpa_system(vcpu, param, NULL);
- srcu_read_unlock(&vcpu->kvm->srcu, idx);
+ struct x86_exception e;
- if (!gpa || kvm_vcpu_read_guest(vcpu, gpa, &send, sizeof(send))) {
+ /* Sanity check: this structure is the same for 32-bit and 64-bit */
+ BUILD_BUG_ON(sizeof(send) != 4);
+ if (kvm_read_guest_virt(vcpu, param, &send, sizeof(send), &e)) {
*r = -EFAULT;
return true;
}
- /* The evtchn_ports idr is protected by vcpu->kvm->srcu */
+ /*
+ * evtchnfd is protected by kvm->srcu; the idr lookup instead
+ * is protected by RCU.
+ */
+ rcu_read_lock();
evtchnfd = idr_find(&vcpu->kvm->arch.xen.evtchn_ports, send.port);
+ rcu_read_unlock();
if (!evtchnfd)
return false;
generated by cgit v1.2.3 (git 2.39.1) at 2025-01-24 08:49:13 +0100