KVM: Simplify ifndef conditional usage in __kvm_set_memory_region()

Narrow down the controlled text inside the conditional so that it will
include lpage_info and rmap stuff only.

For this we change the way we check whether the slot is being created
from "if (npages && !new.rmap)" to "if (npages && !old.npages)".

We also stop checking if lpage_info is NULL when we create lpage_info
because we do it from inside the slot creation code block.

Signed-off-by: Takuya Yoshikawa <yoshikawa.takuya@oss.ntt.co.jp>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 7adaa2063415c4b9782b5bc3a53d647d53fa42ee..a30447c5eb4af94bb78b4debe390a4bc4936aa7b 100644 (file)
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -616,7 +616,6 @@ static int kvm_vm_release(struct inode *inode, struct file *filp)
        return 0;
 }
 
-#ifndef CONFIG_S390
 /*
  * Allocation size is twice as large as the actual dirty bitmap size.
  * This makes it possible to do double buffering: see x86's
@@ -624,6 +623,7 @@ static int kvm_vm_release(struct inode *inode, struct file *filp)
  */
 static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 {
+#ifndef CONFIG_S390
        unsigned long dirty_bytes = 2 * kvm_dirty_bitmap_bytes(memslot);
 
        if (dirty_bytes > PAGE_SIZE)
@@ -636,9 +636,9 @@ static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
 
        memslot->dirty_bitmap_head = memslot->dirty_bitmap;
        memslot->nr_dirty_pages = 0;
+#endif /* !CONFIG_S390 */
        return 0;
 }
-#endif /* !CONFIG_S390 */
 
 static int cmp_memslot(const void *slot1, const void *slot2)
 {
@@ -695,9 +695,6 @@ static int create_lpage_info(struct kvm_memory_slot *slot, unsigned long npages)
                int lpages;
                int level = i + 2;
 
-               if (slot->lpage_info[i])
-                       continue;
-
                lpages = gfn_to_index(slot->base_gfn + npages - 1,
                                      slot->base_gfn, level) + 1;
 
@@ -815,23 +812,18 @@ int __kvm_set_memory_region(struct kvm *kvm,
        r = -ENOMEM;
 
        /* Allocate if a slot is being created */
+       if (npages && !old.npages) {
+               new.user_alloc = user_alloc;
+               new.userspace_addr = mem->userspace_addr;
 #ifndef CONFIG_S390
-       if (npages && !new.rmap) {
                new.rmap = vzalloc(npages * sizeof(*new.rmap));
-
                if (!new.rmap)
                        goto out_free;
 
-               new.user_alloc = user_alloc;
-               new.userspace_addr = mem->userspace_addr;
+               if (create_lpage_info(&new, npages))
+                       goto out_free;
+#endif /* not defined CONFIG_S390 */
        }
-       if (!npages)
-               goto skip_lpage;
-
-       if (create_lpage_info(&new, npages))
-               goto out_free;
-
-skip_lpage:
 
        /* Allocate page dirty bitmap if needed */
        if ((new.flags & KVM_MEM_LOG_DIRTY_PAGES) && !new.dirty_bitmap) {
@@ -839,11 +831,6 @@ skip_lpage:
                        goto out_free;
                /* destroy any largepage mappings for dirty tracking */
        }
-#else  /* not defined CONFIG_S390 */
-       new.user_alloc = user_alloc;
-       if (user_alloc)
-               new.userspace_addr = mem->userspace_addr;
-#endif /* not defined CONFIG_S390 */
 
        if (!npages) {
                struct kvm_memory_slot *slot;