3 files changed, 80 insertions, 7 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 56f7307c21d2..5feaba6a77de 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -1584,6 +1584,8 @@ static int kfd_ioctl_smi_events(struct file *filep,
 	return kfd_smi_event_open(pdd->dev, &args->anon_fd);
 }
 
+#if IS_ENABLED(CONFIG_HSA_AMD_SVM)
+
 static int kfd_ioctl_set_xnack_mode(struct file *filep,
 				    struct kfd_process *p, void *data)
 {
@@ -1594,22 +1596,29 @@ static int kfd_ioctl_set_xnack_mode(struct file *filep,
 	if (args->xnack_enabled >= 0) {
 		if (!list_empty(&p->pqm.queues)) {
 			pr_debug("Process has user queues running\n");
-			mutex_unlock(&p->mutex);
-			return -EBUSY;
+			r = -EBUSY;
+			goto out_unlock;
 		}
-		if (args->xnack_enabled && !kfd_process_xnack_mode(p, true))
+
+		if (p->xnack_enabled == args->xnack_enabled)
+			goto out_unlock;
+
+		if (args->xnack_enabled && !kfd_process_xnack_mode(p, true)) {
 			r = -EPERM;
-		else
-			p->xnack_enabled = args->xnack_enabled;
+			goto out_unlock;
+		}
+
+		r = svm_range_switch_xnack_reserve_mem(p, args->xnack_enabled);
 	} else {
 		args->xnack_enabled = p->xnack_enabled;
 	}
+
+out_unlock:
 	mutex_unlock(&p->mutex);
 
 	return r;
 }
 
-#if IS_ENABLED(CONFIG_HSA_AMD_SVM)
 static int kfd_ioctl_svm(struct file *filep, struct kfd_process *p, void *data)
 {
 	struct kfd_ioctl_svm_args *args = data;
@@ -1629,6 +1638,11 @@ static int kfd_ioctl_svm(struct file *filep, struct kfd_process *p, void *data)
 	return r;
 }
 #else
+static int kfd_ioctl_set_xnack_mode(struct file *filep,
+				    struct kfd_process *p, void *data)
+{
+	return -EPERM;
+}
 static int kfd_ioctl_svm(struct file *filep, struct kfd_process *p, void *data)
 {
 	return -EPERM;
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
index cf5b4005534c..f5913ba22174 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.c
@@ -278,7 +278,7 @@ static void svm_range_free(struct svm_range *prange, bool update_mem_usage)
 	svm_range_free_dma_mappings(prange);
 
 	if (update_mem_usage && !p->xnack_enabled) {
-		pr_debug("unreserve mem limit: %lld\n", size);
+		pr_debug("unreserve prange 0x%p size: 0x%llx\n", prange, size);
 		amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
 					KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
 	}
@@ -2956,6 +2956,64 @@ out:
 	return r;
 }
 
+int
+svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled)
+{
+	struct svm_range *prange, *pchild;
+	uint64_t reserved_size = 0;
+	uint64_t size;
+	int r = 0;
+
+	pr_debug("switching xnack from %d to %d\n", p->xnack_enabled, xnack_enabled);
+
+	mutex_lock(&p->svms.lock);
+
+	list_for_each_entry(prange, &p->svms.list, list) {
+		svm_range_lock(prange);
+		list_for_each_entry(pchild, &prange->child_list, child_list) {
+			size = (pchild->last - pchild->start + 1) << PAGE_SHIFT;
+			if (xnack_enabled) {
+				amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
+						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
+			} else {
+				r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
+						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
+				if (r)
+					goto out_unlock;
+				reserved_size += size;
+			}
+		}
+
+		size = (prange->last - prange->start + 1) << PAGE_SHIFT;
+		if (xnack_enabled) {
+			amdgpu_amdkfd_unreserve_mem_limit(NULL, size,
+						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
+		} else {
+			r = amdgpu_amdkfd_reserve_mem_limit(NULL, size,
+						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
+			if (r)
+				goto out_unlock;
+			reserved_size += size;
+		}
+out_unlock:
+		svm_range_unlock(prange);
+		if (r)
+			break;
+	}
+
+	if (r)
+		amdgpu_amdkfd_unreserve_mem_limit(NULL, reserved_size,
+						KFD_IOC_ALLOC_MEM_FLAGS_USERPTR);
+	else
+		/* Change xnack mode must be inside svms lock, to avoid race with
+		 * svm_range_deferred_list_work unreserve memory in parallel.
+		 */
+		p->xnack_enabled = xnack_enabled;
+
+	mutex_unlock(&p->svms.lock);
+	return r;
+}
+
 void svm_range_list_fini(struct kfd_process *p)
 {
 	struct svm_range *prange;
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
index 012c53729516..7a33b93f9df6 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_svm.h
@@ -203,6 +203,7 @@ void svm_range_list_lock_and_flush_work(struct svm_range_list *svms, struct mm_s
 void svm_range_bo_unref_async(struct svm_range_bo *svm_bo);
 
 void svm_range_set_max_pages(struct amdgpu_device *adev);
+int svm_range_switch_xnack_reserve_mem(struct kfd_process *p, bool xnack_enabled);
 
 #else