ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/virt/kvm/async_pf.c b/marvell/linux/virt/kvm/async_pf.c
new file mode 100644
index 0000000..9e65324
--- /dev/null
+++ b/marvell/linux/virt/kvm/async_pf.c
@@ -0,0 +1,249 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * kvm asynchronous fault support
+ *
+ * Copyright 2010 Red Hat, Inc.
+ *
+ * Author:
+ * Gleb Natapov <gleb@redhat.com>
+ */
+
+#include <linux/kvm_host.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/mmu_context.h>
+#include <linux/sched/mm.h>
+
+#include "async_pf.h"
+#include <trace/events/kvm.h>
+
+static inline void kvm_async_page_present_sync(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+#ifdef CONFIG_KVM_ASYNC_PF_SYNC
+ kvm_arch_async_page_present(vcpu, work);
+#endif
+}
+static inline void kvm_async_page_present_async(struct kvm_vcpu *vcpu,
+ struct kvm_async_pf *work)
+{
+#ifndef CONFIG_KVM_ASYNC_PF_SYNC
+ kvm_arch_async_page_present(vcpu, work);
+#endif
+}
+
+static struct kmem_cache *async_pf_cache;
+
+int kvm_async_pf_init(void)
+{
+ async_pf_cache = KMEM_CACHE(kvm_async_pf, 0);
+
+ if (!async_pf_cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void kvm_async_pf_deinit(void)
+{
+ kmem_cache_destroy(async_pf_cache);
+ async_pf_cache = NULL;
+}
+
+void kvm_async_pf_vcpu_init(struct kvm_vcpu *vcpu)
+{
+ INIT_LIST_HEAD(&vcpu->async_pf.done);
+ INIT_LIST_HEAD(&vcpu->async_pf.queue);
+ spin_lock_init(&vcpu->async_pf.lock);
+}
+
+static void async_pf_execute(struct work_struct *work)
+{
+ struct kvm_async_pf *apf =
+ container_of(work, struct kvm_async_pf, work);
+ struct mm_struct *mm = apf->mm;
+ struct kvm_vcpu *vcpu = apf->vcpu;
+ unsigned long addr = apf->addr;
+ gpa_t cr2_or_gpa = apf->cr2_or_gpa;
+ int locked = 1;
+
+ might_sleep();
+
+ /*
+ * This work is run asynchronously to the task which owns
+ * mm and might be done in another context, so we must
+ * access remotely.
+ */
+ down_read(&mm->mmap_sem);
+ get_user_pages_remote(NULL, mm, addr, 1, FOLL_WRITE, NULL, NULL,
+ &locked);
+ if (locked)
+ up_read(&mm->mmap_sem);
+
+ kvm_async_page_present_sync(vcpu, apf);
+
+ spin_lock(&vcpu->async_pf.lock);
+ list_add_tail(&apf->link, &vcpu->async_pf.done);
+ apf->vcpu = NULL;
+ spin_unlock(&vcpu->async_pf.lock);
+
+ /*
+ * apf may be freed by kvm_check_async_pf_completion() after
+ * this point
+ */
+
+ trace_kvm_async_pf_completed(addr, cr2_or_gpa);
+
+ if (swq_has_sleeper(&vcpu->wq))
+ swake_up_one(&vcpu->wq);
+
+ mmput(mm);
+}
+
+static void kvm_flush_and_free_async_pf_work(struct kvm_async_pf *work)
+{
+ /*
+ * The async #PF is "done", but KVM must wait for the work item itself,
+ * i.e. async_pf_execute(), to run to completion. If KVM is a module,
+ * KVM must ensure *no* code owned by the KVM (the module) can be run
+ * after the last call to module_put(). Note, flushing the work item
+ * is always required when the item is taken off the completion queue.
+ * E.g. even if the vCPU handles the item in the "normal" path, the VM
+ * could be terminated before async_pf_execute() completes.
+ *
+ * Wake all events skip the queue and go straight done, i.e. don't
+ * need to be flushed (but sanity check that the work wasn't queued).
+ */
+ if (work->wakeup_all)
+ WARN_ON_ONCE(work->work.func);
+ else
+ flush_work(&work->work);
+ kmem_cache_free(async_pf_cache, work);
+}
+
+void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu)
+{
+ spin_lock(&vcpu->async_pf.lock);
+
+ /* cancel outstanding work queue item */
+ while (!list_empty(&vcpu->async_pf.queue)) {
+ struct kvm_async_pf *work =
+ list_first_entry(&vcpu->async_pf.queue,
+ typeof(*work), queue);
+ list_del(&work->queue);
+
+ /*
+ * We know it's present in vcpu->async_pf.done, do
+ * nothing here.
+ */
+ if (!work->vcpu)
+ continue;
+
+ spin_unlock(&vcpu->async_pf.lock);
+#ifdef CONFIG_KVM_ASYNC_PF_SYNC
+ flush_work(&work->work);
+#else
+ if (cancel_work_sync(&work->work)) {
+ mmput(work->mm);
+ kmem_cache_free(async_pf_cache, work);
+ }
+#endif
+ spin_lock(&vcpu->async_pf.lock);
+ }
+
+ while (!list_empty(&vcpu->async_pf.done)) {
+ struct kvm_async_pf *work =
+ list_first_entry(&vcpu->async_pf.done,
+ typeof(*work), link);
+ list_del(&work->link);
+
+ spin_unlock(&vcpu->async_pf.lock);
+ kvm_flush_and_free_async_pf_work(work);
+ spin_lock(&vcpu->async_pf.lock);
+ }
+ spin_unlock(&vcpu->async_pf.lock);
+
+ vcpu->async_pf.queued = 0;
+}
+
+void kvm_check_async_pf_completion(struct kvm_vcpu *vcpu)
+{
+ struct kvm_async_pf *work;
+
+ while (!list_empty_careful(&vcpu->async_pf.done) &&
+ kvm_arch_can_inject_async_page_present(vcpu)) {
+ spin_lock(&vcpu->async_pf.lock);
+ work = list_first_entry(&vcpu->async_pf.done, typeof(*work),
+ link);
+ list_del(&work->link);
+ spin_unlock(&vcpu->async_pf.lock);
+
+ kvm_arch_async_page_ready(vcpu, work);
+ kvm_async_page_present_async(vcpu, work);
+
+ list_del(&work->queue);
+ vcpu->async_pf.queued--;
+ kvm_flush_and_free_async_pf_work(work);
+ }
+}
+
+int kvm_setup_async_pf(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa,
+ unsigned long hva, struct kvm_arch_async_pf *arch)
+{
+ struct kvm_async_pf *work;
+
+ if (vcpu->async_pf.queued >= ASYNC_PF_PER_VCPU)
+ return 0;
+
+ /* Arch specific code should not do async PF in this case */
+ if (unlikely(kvm_is_error_hva(hva)))
+ return 0;
+
+ /*
+ * do alloc nowait since if we are going to sleep anyway we
+ * may as well sleep faulting in page
+ */
+ work = kmem_cache_zalloc(async_pf_cache, GFP_NOWAIT | __GFP_NOWARN);
+ if (!work)
+ return 0;
+
+ work->wakeup_all = false;
+ work->vcpu = vcpu;
+ work->cr2_or_gpa = cr2_or_gpa;
+ work->addr = hva;
+ work->arch = *arch;
+ work->mm = current->mm;
+ mmget(work->mm);
+
+ INIT_WORK(&work->work, async_pf_execute);
+
+ list_add_tail(&work->queue, &vcpu->async_pf.queue);
+ vcpu->async_pf.queued++;
+ kvm_arch_async_page_not_present(vcpu, work);
+
+ schedule_work(&work->work);
+
+ return 1;
+}
+
+int kvm_async_pf_wakeup_all(struct kvm_vcpu *vcpu)
+{
+ struct kvm_async_pf *work;
+
+ if (!list_empty_careful(&vcpu->async_pf.done))
+ return 0;
+
+ work = kmem_cache_zalloc(async_pf_cache, GFP_ATOMIC);
+ if (!work)
+ return -ENOMEM;
+
+ work->wakeup_all = true;
+ INIT_LIST_HEAD(&work->queue); /* for list_del to work */
+
+ spin_lock(&vcpu->async_pf.lock);
+ list_add_tail(&work->link, &vcpu->async_pf.done);
+ spin_unlock(&vcpu->async_pf.lock);
+
+ vcpu->async_pf.queued++;
+ return 0;
+}