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-rw-r--r--virt/kvm/arm/arm.c48
-rw-r--r--virt/kvm/kvm_main.c91
2 files changed, 75 insertions, 64 deletions
diff --git a/virt/kvm/arm/arm.c b/virt/kvm/arm/arm.c
index d65a0faa46d8..bfdba1caf59d 100644
--- a/virt/kvm/arm/arm.c
+++ b/virt/kvm/arm/arm.c
@@ -1183,55 +1183,15 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
return r;
}
-/**
- * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
- * @kvm: kvm instance
- * @log: slot id and address to which we copy the log
- *
- * Steps 1-4 below provide general overview of dirty page logging. See
- * kvm_get_dirty_log_protect() function description for additional details.
- *
- * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
- * always flush the TLB (step 4) even if previous step failed and the dirty
- * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
- * does not preclude user space subsequent dirty log read. Flushing TLB ensures
- * writes will be marked dirty for next log read.
- *
- * 1. Take a snapshot of the bit and clear it if needed.
- * 2. Write protect the corresponding page.
- * 3. Copy the snapshot to the userspace.
- * 4. Flush TLB's if needed.
- */
-int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log)
+void kvm_arch_sync_dirty_log(struct kvm *kvm, struct kvm_memory_slot *memslot)
{
- bool flush = false;
- int r;
-
- mutex_lock(&kvm->slots_lock);
-
- r = kvm_get_dirty_log_protect(kvm, log, &flush);
- if (flush)
- kvm_flush_remote_tlbs(kvm);
-
- mutex_unlock(&kvm->slots_lock);
- return r;
}
-int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm, struct kvm_clear_dirty_log *log)
+void kvm_arch_flush_remote_tlbs_memslot(struct kvm *kvm,
+ struct kvm_memory_slot *memslot)
{
- bool flush = false;
- int r;
-
- mutex_lock(&kvm->slots_lock);
-
- r = kvm_clear_dirty_log_protect(kvm, log, &flush);
-
- if (flush)
- kvm_flush_remote_tlbs(kvm);
-
- mutex_unlock(&kvm->slots_lock);
- return r;
+ kvm_flush_remote_tlbs(kvm);
}
static int kvm_vm_ioctl_set_device_addr(struct kvm *kvm,
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 1632e466ad6f..7420aa468b75 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -856,7 +856,7 @@ static int kvm_vm_release(struct inode *inode, struct file *filp)
/*
* Allocation size is twice as large as the actual dirty bitmap size.
- * See x86's kvm_vm_ioctl_get_dirty_log() why this is needed.
+ * See kvm_vm_ioctl_get_dirty_log() why this is needed.
*/
static int kvm_create_dirty_bitmap(struct kvm_memory_slot *memslot)
{
@@ -1104,12 +1104,9 @@ int __kvm_set_memory_region(struct kvm *kvm,
* Make a full copy of the old memslot, the pointer will become stale
* when the memslots are re-sorted by update_memslots(), and the old
* memslot needs to be referenced after calling update_memslots(), e.g.
- * to free its resources and for arch specific behavior. Kill @tmp
- * after making a copy to deter potentially dangerous usage.
+ * to free its resources and for arch specific behavior.
*/
- tmp = id_to_memslot(__kvm_memslots(kvm, as_id), id);
- old = *tmp;
- tmp = NULL;
+ old = *id_to_memslot(__kvm_memslots(kvm, as_id), id);
if (!mem->memory_size)
return kvm_delete_memslot(kvm, mem, &old, as_id);
@@ -1201,6 +1198,7 @@ static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
return kvm_set_memory_region(kvm, mem);
}
+#ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
int kvm_get_dirty_log(struct kvm *kvm,
struct kvm_dirty_log *log, int *is_dirty)
{
@@ -1234,13 +1232,12 @@ int kvm_get_dirty_log(struct kvm *kvm,
}
EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
-#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
+#else /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
/**
* kvm_get_dirty_log_protect - get a snapshot of dirty pages
* and reenable dirty page tracking for the corresponding pages.
* @kvm: pointer to kvm instance
* @log: slot id and address to which we copy the log
- * @flush: true if TLB flush is needed by caller
*
* We need to keep it in mind that VCPU threads can write to the bitmap
* concurrently. So, to avoid losing track of dirty pages we keep the
@@ -1257,8 +1254,7 @@ EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
* exiting to userspace will be logged for the next call.
*
*/
-int kvm_get_dirty_log_protect(struct kvm *kvm,
- struct kvm_dirty_log *log, bool *flush)
+static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
{
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;
@@ -1266,6 +1262,7 @@ int kvm_get_dirty_log_protect(struct kvm *kvm,
unsigned long n;
unsigned long *dirty_bitmap;
unsigned long *dirty_bitmap_buffer;
+ bool flush;
as_id = log->slot >> 16;
id = (u16)log->slot;
@@ -1279,8 +1276,10 @@ int kvm_get_dirty_log_protect(struct kvm *kvm,
if (!dirty_bitmap)
return -ENOENT;
+ kvm_arch_sync_dirty_log(kvm, memslot);
+
n = kvm_dirty_bitmap_bytes(memslot);
- *flush = false;
+ flush = false;
if (kvm->manual_dirty_log_protect) {
/*
* Unlike kvm_get_dirty_log, we always return false in *flush,
@@ -1303,7 +1302,7 @@ int kvm_get_dirty_log_protect(struct kvm *kvm,
if (!dirty_bitmap[i])
continue;
- *flush = true;
+ flush = true;
mask = xchg(&dirty_bitmap[i], 0);
dirty_bitmap_buffer[i] = mask;
@@ -1314,21 +1313,55 @@ int kvm_get_dirty_log_protect(struct kvm *kvm,
spin_unlock(&kvm->mmu_lock);
}
+ if (flush)
+ kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+
if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
return -EFAULT;
return 0;
}
-EXPORT_SYMBOL_GPL(kvm_get_dirty_log_protect);
+
+
+/**
+ * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
+ * @kvm: kvm instance
+ * @log: slot id and address to which we copy the log
+ *
+ * Steps 1-4 below provide general overview of dirty page logging. See
+ * kvm_get_dirty_log_protect() function description for additional details.
+ *
+ * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
+ * always flush the TLB (step 4) even if previous step failed and the dirty
+ * bitmap may be corrupt. Regardless of previous outcome the KVM logging API
+ * does not preclude user space subsequent dirty log read. Flushing TLB ensures
+ * writes will be marked dirty for next log read.
+ *
+ * 1. Take a snapshot of the bit and clear it if needed.
+ * 2. Write protect the corresponding page.
+ * 3. Copy the snapshot to the userspace.
+ * 4. Flush TLB's if needed.
+ */
+static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
+ struct kvm_dirty_log *log)
+{
+ int r;
+
+ mutex_lock(&kvm->slots_lock);
+
+ r = kvm_get_dirty_log_protect(kvm, log);
+
+ mutex_unlock(&kvm->slots_lock);
+ return r;
+}
/**
* kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
* and reenable dirty page tracking for the corresponding pages.
* @kvm: pointer to kvm instance
* @log: slot id and address from which to fetch the bitmap of dirty pages
- * @flush: true if TLB flush is needed by caller
*/
-int kvm_clear_dirty_log_protect(struct kvm *kvm,
- struct kvm_clear_dirty_log *log, bool *flush)
+static int kvm_clear_dirty_log_protect(struct kvm *kvm,
+ struct kvm_clear_dirty_log *log)
{
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;
@@ -1337,6 +1370,7 @@ int kvm_clear_dirty_log_protect(struct kvm *kvm,
unsigned long i, n;
unsigned long *dirty_bitmap;
unsigned long *dirty_bitmap_buffer;
+ bool flush;
as_id = log->slot >> 16;
id = (u16)log->slot;
@@ -1360,7 +1394,9 @@ int kvm_clear_dirty_log_protect(struct kvm *kvm,
(log->num_pages < memslot->npages - log->first_page && (log->num_pages & 63)))
return -EINVAL;
- *flush = false;
+ kvm_arch_sync_dirty_log(kvm, memslot);
+
+ flush = false;
dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
return -EFAULT;
@@ -1383,17 +1419,32 @@ int kvm_clear_dirty_log_protect(struct kvm *kvm,
* a problem if userspace sets them in log->dirty_bitmap.
*/
if (mask) {
- *flush = true;
+ flush = true;
kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
offset, mask);
}
}
spin_unlock(&kvm->mmu_lock);
+ if (flush)
+ kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
+
return 0;
}
-EXPORT_SYMBOL_GPL(kvm_clear_dirty_log_protect);
-#endif
+
+static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm,
+ struct kvm_clear_dirty_log *log)
+{
+ int r;
+
+ mutex_lock(&kvm->slots_lock);
+
+ r = kvm_clear_dirty_log_protect(kvm, log);
+
+ mutex_unlock(&kvm->slots_lock);
+ return r;
+}
+#endif /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
bool kvm_largepages_enabled(void)
{