[PATCH v2 7/9] virtio-mem: use a single dynamic memory group for a single virtio-mem device

From: David Hildenbrand <david@redhat.com>
To: linux-kernel@vger.kernel.org
Cc: linux-mm@kvack.org, David Hildenbrand <david@redhat.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Vitaly Kuznetsov <vkuznets@redhat.com>,
	"Michael S. Tsirkin" <mst@redhat.com>,
	Jason Wang <jasowang@redhat.com>,
	Marek Kedzierski <mkedzier@redhat.com>,
	Hui Zhu <teawater@gmail.com>,
	Pankaj Gupta <pankaj.gupta.linux@gmail.com>,
	Wei Yang <richard.weiyang@linux.alibaba.com>,
	Oscar Salvador <osalvador@suse.de>,
	Michal Hocko <mhocko@kernel.org>,
	Dan Williams <dan.j.williams@intel.com>,
	Anshuman Khandual <anshuman.khandual@arm.com>,
	Dave Hansen <dave.hansen@linux.intel.com>,
	Vlastimil Babka <vbabka@suse.cz>, Mike Rapoport <rppt@kernel.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Len Brown <lenb@kernel.org>,
	Pavel Tatashin <pasha.tatashin@soleen.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	virtualization@lists.linux-foundation.org,
	linux-acpi@vger.kernel.org
Subject: [PATCH v2 7/9] virtio-mem: use a single dynamic memory group for a single virtio-mem device
Date: Fri, 23 Jul 2021 14:52:08 +0200	[thread overview]
Message-ID: <20210723125210.29987-8-david@redhat.com> (raw)
In-Reply-To: <20210723125210.29987-1-david@redhat.com>

Let's use a single dynamic memory group.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 drivers/virtio/virtio_mem.c | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 774986695dc4..19036922f7ef 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -143,6 +143,8 @@ struct virtio_mem {
 	 * add_memory_driver_managed().
 	 */
 	const char *resource_name;
+	/* Memory group identification. */
+	int mgid;
 
 	/*
 	 * We don't want to add too much memory if it's not getting onlined,
@@ -626,8 +628,8 @@ static int virtio_mem_add_memory(struct virtio_mem *vm, uint64_t addr,
 		addr + size - 1);
 	/* Memory might get onlined immediately. */
 	atomic64_add(size, &vm->offline_size);
-	rc = add_memory_driver_managed(vm->nid, addr, size, vm->resource_name,
-				       MHP_MERGE_RESOURCE);
+	rc = add_memory_driver_managed(vm->mgid, addr, size, vm->resource_name,
+				       MHP_MERGE_RESOURCE | MHP_NID_IS_MGID);
 	if (rc) {
 		atomic64_sub(size, &vm->offline_size);
 		dev_warn(&vm->vdev->dev, "adding memory failed: %d\n", rc);
@@ -2562,6 +2564,7 @@ static bool virtio_mem_has_memory_added(struct virtio_mem *vm)
 static int virtio_mem_probe(struct virtio_device *vdev)
 {
 	struct virtio_mem *vm;
+	uint64_t unit_pages;
 	int rc;
 
 	BUILD_BUG_ON(sizeof(struct virtio_mem_req) != 24);
@@ -2596,6 +2599,16 @@ static int virtio_mem_probe(struct virtio_device *vdev)
 	if (rc)
 		goto out_del_vq;
 
+	/* use a single dynamic memory group to cover the whole memory device */
+	if (vm->in_sbm)
+		unit_pages = PHYS_PFN(memory_block_size_bytes());
+	else
+		unit_pages = PHYS_PFN(vm->bbm.bb_size);
+	rc = register_dynamic_memory_group(vm->nid, unit_pages);
+	if (rc < 0)
+		goto out_del_resource;
+	vm->mgid = rc;
+
 	/*
 	 * If we still have memory plugged, we have to unplug all memory first.
 	 * Registering our parent resource makes sure that this memory isn't
@@ -2610,7 +2623,7 @@ static int virtio_mem_probe(struct virtio_device *vdev)
 	vm->memory_notifier.notifier_call = virtio_mem_memory_notifier_cb;
 	rc = register_memory_notifier(&vm->memory_notifier);
 	if (rc)
-		goto out_del_resource;
+		goto out_unreg_group;
 	rc = register_virtio_mem_device(vm);
 	if (rc)
 		goto out_unreg_mem;
@@ -2624,6 +2637,8 @@ static int virtio_mem_probe(struct virtio_device *vdev)
 	return 0;
 out_unreg_mem:
 	unregister_memory_notifier(&vm->memory_notifier);
+out_unreg_group:
+	unregister_memory_group(vm->mgid);
 out_del_resource:
 	virtio_mem_delete_resource(vm);
 out_del_vq:
@@ -2688,6 +2703,7 @@ static void virtio_mem_remove(struct virtio_device *vdev)
 	} else {
 		virtio_mem_delete_resource(vm);
 		kfree_const(vm->resource_name);
+		unregister_memory_group(vm->mgid);
 	}
 
 	/* remove all tracking data - no locking needed */
-- 
2.31.1

