virtio-mem: use a single dynamic memory group for a single virtio-mem device

Let's use a single dynamic memory group.

Link: https://lkml.kernel.org/r/20210806124715.17090-8-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Hui Zhu <teawater@gmail.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Len Brown <lenb@kernel.org>
Cc: Marek Kedzierski <mkedzier@redhat.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index 7e83ed3..bef8ad6 100644 (file)
--- 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);
@@ -2569,6 +2571,7 @@ 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);
@@ -2603,6 +2606,16 @@ 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 = memory_group_register_dynamic(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
@@ -2617,7 +2630,7 @@ 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;
@@ -2631,6 +2644,8 @@ static int virtio_mem_probe(struct virtio_device *vdev)
        return 0;
 out_unreg_mem:
        unregister_memory_notifier(&vm->memory_notifier);
+out_unreg_group:
+       memory_group_unregister(vm->mgid);
 out_del_resource:
        virtio_mem_delete_resource(vm);
 out_del_vq:
@@ -2695,6 +2710,7 @@ static void virtio_mem_remove(struct virtio_device *vdev)
        } else {
                virtio_mem_delete_resource(vm);
                kfree_const(vm->resource_name);
+               memory_group_unregister(vm->mgid);
        }
 
        /* remove all tracking data - no locking needed */