1 files changed, 49 insertions, 121 deletions

diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index c06c89d370a7..d29f575fb372 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -2,7 +2,7 @@
 /*
  * handling kvm guest interrupts
  *
- * Copyright IBM Corp. 2008, 2015
+ * Copyright IBM Corp. 2008, 2020
  *
  *    Author(s): Carsten Otte <cotte@de.ibm.com>
  */
@@ -2327,9 +2327,6 @@ static int register_io_adapter(struct kvm_device *dev,
 	if (!adapter)
 		return -ENOMEM;
 
-	INIT_LIST_HEAD(&adapter->maps);
-	init_rwsem(&adapter->maps_lock);
-	atomic_set(&adapter->nr_maps, 0);
 	adapter->id = adapter_info.id;
 	adapter->isc = adapter_info.isc;
 	adapter->maskable = adapter_info.maskable;
@@ -2354,87 +2351,12 @@ int kvm_s390_mask_adapter(struct kvm *kvm, unsigned int id, bool masked)
 	return ret;
 }
 
-static int kvm_s390_adapter_map(struct kvm *kvm, unsigned int id, __u64 addr)
-{
-	struct s390_io_adapter *adapter = get_io_adapter(kvm, id);
-	struct s390_map_info *map;
-	int ret;
-
-	if (!adapter || !addr)
-		return -EINVAL;
-
-	map = kzalloc(sizeof(*map), GFP_KERNEL);
-	if (!map) {
-		ret = -ENOMEM;
-		goto out;
-	}
-	INIT_LIST_HEAD(&map->list);
-	map->guest_addr = addr;
-	map->addr = gmap_translate(kvm->arch.gmap, addr);
-	if (map->addr == -EFAULT) {
-		ret = -EFAULT;
-		goto out;
-	}
-	ret = get_user_pages_fast(map->addr, 1, FOLL_WRITE, &map->page);
-	if (ret < 0)
-		goto out;
-	BUG_ON(ret != 1);
-	down_write(&adapter->maps_lock);
-	if (atomic_inc_return(&adapter->nr_maps) < MAX_S390_ADAPTER_MAPS) {
-		list_add_tail(&map->list, &adapter->maps);
-		ret = 0;
-	} else {
-		put_page(map->page);
-		ret = -EINVAL;
-	}
-	up_write(&adapter->maps_lock);
-out:
-	if (ret)
-		kfree(map);
-	return ret;
-}
-
-static int kvm_s390_adapter_unmap(struct kvm *kvm, unsigned int id, __u64 addr)
-{
-	struct s390_io_adapter *adapter = get_io_adapter(kvm, id);
-	struct s390_map_info *map, *tmp;
-	int found = 0;
-
-	if (!adapter || !addr)
-		return -EINVAL;
-
-	down_write(&adapter->maps_lock);
-	list_for_each_entry_safe(map, tmp, &adapter->maps, list) {
-		if (map->guest_addr == addr) {
-			found = 1;
-			atomic_dec(&adapter->nr_maps);
-			list_del(&map->list);
-			put_page(map->page);
-			kfree(map);
-			break;
-		}
-	}
-	up_write(&adapter->maps_lock);
-
-	return found ? 0 : -EINVAL;
-}
-
 void kvm_s390_destroy_adapters(struct kvm *kvm)
 {
 	int i;
-	struct s390_map_info *map, *tmp;
 
-	for (i = 0; i < MAX_S390_IO_ADAPTERS; i++) {
-		if (!kvm->arch.adapters[i])
-			continue;
-		list_for_each_entry_safe(map, tmp,
-					 &kvm->arch.adapters[i]->maps, list) {
-			list_del(&map->list);
-			put_page(map->page);
-			kfree(map);
-		}
+	for (i = 0; i < MAX_S390_IO_ADAPTERS; i++)
 		kfree(kvm->arch.adapters[i]);
-	}
 }
 
 static int modify_io_adapter(struct kvm_device *dev,
@@ -2456,11 +2378,14 @@ static int modify_io_adapter(struct kvm_device *dev,
 		if (ret > 0)
 			ret = 0;
 		break;
+	/*
+	 * The following operations are no longer needed and therefore no-ops.
+	 * The gpa to hva translation is done when an IRQ route is set up. The
+	 * set_irq code uses get_user_pages_remote() to do the actual write.
+	 */
 	case KVM_S390_IO_ADAPTER_MAP:
-		ret = kvm_s390_adapter_map(dev->kvm, req.id, req.addr);
-		break;
 	case KVM_S390_IO_ADAPTER_UNMAP:
-		ret = kvm_s390_adapter_unmap(dev->kvm, req.id, req.addr);
+		ret = 0;
 		break;
 	default:
 		ret = -EINVAL;
@@ -2699,19 +2624,15 @@ static unsigned long get_ind_bit(__u64 addr, unsigned long bit_nr, bool swap)
 	return swap ? (bit ^ (BITS_PER_LONG - 1)) : bit;
 }
 
-static struct s390_map_info *get_map_info(struct s390_io_adapter *adapter,
-					  u64 addr)
+static struct page *get_map_page(struct kvm *kvm, u64 uaddr)
 {
-	struct s390_map_info *map;
+	struct page *page = NULL;
 
-	if (!adapter)
-		return NULL;
-
-	list_for_each_entry(map, &adapter->maps, list) {
-		if (map->guest_addr == addr)
-			return map;
-	}
-	return NULL;
+	down_read(&kvm->mm->mmap_sem);
+	get_user_pages_remote(NULL, kvm->mm, uaddr, 1, FOLL_WRITE,
+			      &page, NULL, NULL);
+	up_read(&kvm->mm->mmap_sem);
+	return page;
 }
 
 static int adapter_indicators_set(struct kvm *kvm,
@@ -2720,30 +2641,35 @@ static int adapter_indicators_set(struct kvm *kvm,
 {
 	unsigned long bit;
 	int summary_set, idx;
-	struct s390_map_info *info;
+	struct page *ind_page, *summary_page;
 	void *map;
 
-	info = get_map_info(adapter, adapter_int->ind_addr);
-	if (!info)
+	ind_page = get_map_page(kvm, adapter_int->ind_addr);
+	if (!ind_page)
 		return -1;
-	map = page_address(info->page);
-	bit = get_ind_bit(info->addr, adapter_int->ind_offset, adapter->swap);
-	set_bit(bit, map);
-	idx = srcu_read_lock(&kvm->srcu);
-	mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT);
-	set_page_dirty_lock(info->page);
-	info = get_map_info(adapter, adapter_int->summary_addr);
-	if (!info) {
-		srcu_read_unlock(&kvm->srcu, idx);
+	summary_page = get_map_page(kvm, adapter_int->summary_addr);
+	if (!summary_page) {
+		put_page(ind_page);
 		return -1;
 	}
-	map = page_address(info->page);
-	bit = get_ind_bit(info->addr, adapter_int->summary_offset,
-			  adapter->swap);
+
+	idx = srcu_read_lock(&kvm->srcu);
+	map = page_address(ind_page);
+	bit = get_ind_bit(adapter_int->ind_addr,
+			  adapter_int->ind_offset, adapter->swap);
+	set_bit(bit, map);
+	mark_page_dirty(kvm, adapter_int->ind_addr >> PAGE_SHIFT);
+	set_page_dirty_lock(ind_page);
+	map = page_address(summary_page);
+	bit = get_ind_bit(adapter_int->summary_addr,
+			  adapter_int->summary_offset, adapter->swap);
 	summary_set = test_and_set_bit(bit, map);
-	mark_page_dirty(kvm, info->guest_addr >> PAGE_SHIFT);
-	set_page_dirty_lock(info->page);
+	mark_page_dirty(kvm, adapter_int->summary_addr >> PAGE_SHIFT);
+	set_page_dirty_lock(summary_page);
 	srcu_read_unlock(&kvm->srcu, idx);
+
+	put_page(ind_page);
+	put_page(summary_page);
 	return summary_set ? 0 : 1;
 }
 
@@ -2765,9 +2691,7 @@ static int set_adapter_int(struct kvm_kernel_irq_routing_entry *e,
 	adapter = get_io_adapter(kvm, e->adapter.adapter_id);
 	if (!adapter)
 		return -1;
-	down_read(&adapter->maps_lock);
 	ret = adapter_indicators_set(kvm, adapter, &e->adapter);
-	up_read(&adapter->maps_lock);
 	if ((ret > 0) && !adapter->masked) {
 		ret = kvm_s390_inject_airq(kvm, adapter);
 		if (ret == 0)
@@ -2818,23 +2742,27 @@ int kvm_set_routing_entry(struct kvm *kvm,
 			  struct kvm_kernel_irq_routing_entry *e,
 			  const struct kvm_irq_routing_entry *ue)
 {
-	int ret;
+	u64 uaddr;
 
 	switch (ue->type) {
+	/* we store the userspace addresses instead of the guest addresses */
 	case KVM_IRQ_ROUTING_S390_ADAPTER:
 		e->set = set_adapter_int;
-		e->adapter.summary_addr = ue->u.adapter.summary_addr;
-		e->adapter.ind_addr = ue->u.adapter.ind_addr;
+		uaddr =  gmap_translate(kvm->arch.gmap, ue->u.adapter.summary_addr);
+		if (uaddr == -EFAULT)
+			return -EFAULT;
+		e->adapter.summary_addr = uaddr;
+		uaddr =  gmap_translate(kvm->arch.gmap, ue->u.adapter.ind_addr);
+		if (uaddr == -EFAULT)
+			return -EFAULT;
+		e->adapter.ind_addr = uaddr;
 		e->adapter.summary_offset = ue->u.adapter.summary_offset;
 		e->adapter.ind_offset = ue->u.adapter.ind_offset;
 		e->adapter.adapter_id = ue->u.adapter.adapter_id;
-		ret = 0;
-		break;
+		return 0;
 	default:
-		ret = -EINVAL;
+		return -EINVAL;
 	}
-
-	return ret;
 }
 
 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *e, struct kvm *kvm,