KVM: Split lpage_info creation out from __kvm_set_memory_region()

This makes it easy to make lpage_info architecture specific.

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>

1 files changed, 52 insertions, 31 deletions

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 415fe816fc15..7adaa2063415 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -685,6 +685,56 @@ void update_memslots(struct kvm_memslots *slots, struct kvm_memory_slot *new)
         slots->generation++;
 }
 
+#ifndef CONFIG_S390
+static int create_lpage_info(struct kvm_memory_slot *slot, unsigned long npages)
+{
+        int i;
+
+        for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
+                unsigned long ugfn;
+                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;
+
+                slot->lpage_info[i] = vzalloc(lpages * sizeof(*slot->lpage_info[i]));
+                if (!slot->lpage_info[i])
+                        goto out_free;
+
+                if (slot->base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
+                        slot->lpage_info[i][0].write_count = 1;
+                if ((slot->base_gfn + npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
+                        slot->lpage_info[i][lpages - 1].write_count = 1;
+                ugfn = slot->userspace_addr >> PAGE_SHIFT;
+                /*
+                 * If the gfn and userspace address are not aligned wrt each
+                 * other, or if explicitly asked to, disable large page
+                 * support for this slot
+                 */
+                if ((slot->base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
+                    !largepages_enabled) {
+                        unsigned long j;
+
+                        for (j = 0; j < lpages; ++j)
+                                slot->lpage_info[i][j].write_count = 1;
+                }
+        }
+
+        return 0;
+
+out_free:
+        for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
+                vfree(slot->lpage_info[i]);
+                slot->lpage_info[i] = NULL;
+        }
+        return -ENOMEM;
+}
+#endif /* not defined CONFIG_S390 */
+
 /*
  * Allocate some memory and give it an address in the guest physical address
  * space.
@@ -778,37 +828,8 @@ int __kvm_set_memory_region(struct kvm *kvm,
         if (!npages)
                 goto skip_lpage;
 
-        for (i = 0; i < KVM_NR_PAGE_SIZES - 1; ++i) {
-                unsigned long ugfn;
-                unsigned long j;
-                int lpages;
-                int level = i + 2;
-
-                if (new.lpage_info[i])
-                        continue;
-
-                lpages = gfn_to_index(base_gfn + npages - 1, base_gfn, level) + 1;
-
-                new.lpage_info[i] = vzalloc(lpages * sizeof(*new.lpage_info[i]));
-
-                if (!new.lpage_info[i])
-                        goto out_free;
-
-                if (base_gfn & (KVM_PAGES_PER_HPAGE(level) - 1))
-                        new.lpage_info[i][0].write_count = 1;
-                if ((base_gfn+npages) & (KVM_PAGES_PER_HPAGE(level) - 1))
-                        new.lpage_info[i][lpages - 1].write_count = 1;
-                ugfn = new.userspace_addr >> PAGE_SHIFT;
-                /*
-                 * If the gfn and userspace address are not aligned wrt each
-                 * other, or if explicitly asked to, disable large page
-                 * support for this slot
-                 */
-                if ((base_gfn ^ ugfn) & (KVM_PAGES_PER_HPAGE(level) - 1) ||
-                    !largepages_enabled)
-                        for (j = 0; j < lpages; ++j)
-                                new.lpage_info[i][j].write_count = 1;
-        }
+        if (create_lpage_info(&new, npages))
+                goto out_free;
 
 skip_lpage: