From 15f36ebd34b5b296c274ef67024f14c2d394a507 Mon Sep 17 00:00:00 2001 From: "Jason J. Herne" Date: Thu, 2 Aug 2012 10:10:17 -0400 Subject: [PATCH] KVM: s390: Add proper dirty bitmap support to S390 kvm. Replace the kvm_s390_sync_dirty_log() stub with code to construct the KVM dirty_bitmap from S390 memory change bits. Also add code to properly clear the dirty_bitmap size when clearing the bitmap. Signed-off-by: Jason J. Herne CC: Dominik Dingel [Dominik Dingel: use gmap_test_and_clear_dirty, locking fixes] Signed-off-by: Christian Borntraeger --- arch/s390/kvm/kvm-s390.c | 51 +++++++++++++++++++++++++++++++++++++++- virt/kvm/kvm_main.c | 2 -- 2 files changed, 50 insertions(+), 3 deletions(-) diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c index b767ec97368a..346a3478dd00 100644 --- a/arch/s390/kvm/kvm-s390.c +++ b/arch/s390/kvm/kvm-s390.c @@ -11,6 +11,7 @@ * Christian Borntraeger * Heiko Carstens * Christian Ehrhardt + * Jason J. Herne */ #include @@ -179,6 +180,25 @@ int kvm_dev_ioctl_check_extension(long ext) return r; } +static void kvm_s390_sync_dirty_log(struct kvm *kvm, + struct kvm_memory_slot *memslot) +{ + gfn_t cur_gfn, last_gfn; + unsigned long address; + struct gmap *gmap = kvm->arch.gmap; + + down_read(&gmap->mm->mmap_sem); + /* Loop over all guest pages */ + last_gfn = memslot->base_gfn + memslot->npages; + for (cur_gfn = memslot->base_gfn; cur_gfn <= last_gfn; cur_gfn++) { + address = gfn_to_hva_memslot(memslot, cur_gfn); + + if (gmap_test_and_clear_dirty(address, gmap)) + mark_page_dirty(kvm, cur_gfn); + } + up_read(&gmap->mm->mmap_sem); +} + /* Section: vm related */ /* * Get (and clear) the dirty memory log for a memory slot. @@ -186,7 +206,36 @@ int kvm_dev_ioctl_check_extension(long ext) int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) { - return 0; + int r; + unsigned long n; + struct kvm_memory_slot *memslot; + int is_dirty = 0; + + mutex_lock(&kvm->slots_lock); + + r = -EINVAL; + if (log->slot >= KVM_USER_MEM_SLOTS) + goto out; + + memslot = id_to_memslot(kvm->memslots, log->slot); + r = -ENOENT; + if (!memslot->dirty_bitmap) + goto out; + + kvm_s390_sync_dirty_log(kvm, memslot); + r = kvm_get_dirty_log(kvm, log, &is_dirty); + if (r) + goto out; + + /* Clear the dirty log */ + if (is_dirty) { + n = kvm_dirty_bitmap_bytes(memslot); + memset(memslot->dirty_bitmap, 0, n); + } + r = 0; +out: + mutex_unlock(&kvm->slots_lock); + return r; } static int kvm_vm_ioctl_enable_cap(struct kvm *kvm, struct kvm_enable_cap *cap) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 56baae8c2f56..7facdb1f1374 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -637,14 +637,12 @@ 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); memslot->dirty_bitmap = kvm_kvzalloc(dirty_bytes); if (!memslot->dirty_bitmap) return -ENOMEM; -#endif /* !CONFIG_S390 */ return 0; } -- 2.20.1