[PATCH v2 6/9] virtio-mem: factor out hotplug specifics from virtio_mem_init() into virtio_mem_init_hotplug()

[David Hildenbrand <david@xxxxxxxxxx>]

Let's prepare for a new virtio-mem kdump mode in which we don't actually
hot(un)plug any memory but only observe the state of device blocks.

Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
---
 drivers/virtio/virtio_mem.c | 81 ++++++++++++++++++++-----------------
 1 file changed, 44 insertions(+), 37 deletions(-)

diff --git a/drivers/virtio/virtio_mem.c b/drivers/virtio/virtio_mem.c
index bef8ad6bf466..2ba7e8d6ba8d 100644
--- a/drivers/virtio/virtio_mem.c
+++ b/drivers/virtio/virtio_mem.c
@@ -2392,41 +2392,10 @@ static int virtio_mem_init_vq(struct virtio_mem *vm)
        return 0;
 }
 
-static int virtio_mem_init(struct virtio_mem *vm)
+static int virtio_mem_init_hotplug(struct virtio_mem *vm)
 {
        const struct range pluggable_range = mhp_get_pluggable_range(true);
        uint64_t sb_size, addr;
-       uint16_t node_id;
-
-       if (!vm->vdev->config->get) {
-               dev_err(&vm->vdev->dev, "config access disabled\n");
-               return -EINVAL;
-       }
-
-       /*
-        * We don't want to (un)plug or reuse any memory when in kdump. The
-        * memory is still accessible (but not mapped).
-        */
-       if (is_kdump_kernel()) {
-               dev_warn(&vm->vdev->dev, "disabled in kdump kernel\n");
-               return -EBUSY;
-       }
-
-       /* Fetch all properties that can't change. */
-       virtio_cread_le(vm->vdev, struct virtio_mem_config, plugged_size,
-                       &vm->plugged_size);
-       virtio_cread_le(vm->vdev, struct virtio_mem_config, block_size,
-                       &vm->device_block_size);
-       virtio_cread_le(vm->vdev, struct virtio_mem_config, node_id,
-                       &node_id);
-       vm->nid = virtio_mem_translate_node_id(vm, node_id);
-       virtio_cread_le(vm->vdev, struct virtio_mem_config, addr, &vm->addr);
-       virtio_cread_le(vm->vdev, struct virtio_mem_config, region_size,
-                       &vm->region_size);
-
-       /* Determine the nid for the device based on the lowest address. */
-       if (vm->nid == NUMA_NO_NODE)
-               vm->nid = memory_add_physaddr_to_nid(vm->addr);
 
        /* bad device setup - warn only */
        if (!IS_ALIGNED(vm->addr, memory_block_size_bytes()))
@@ -2496,10 +2465,6 @@ static int virtio_mem_init(struct virtio_mem *vm)
                                              vm->offline_threshold);
        }
 
-       dev_info(&vm->vdev->dev, "start address: 0x%llx", vm->addr);
-       dev_info(&vm->vdev->dev, "region size: 0x%llx", vm->region_size);
-       dev_info(&vm->vdev->dev, "device block size: 0x%llx",
-                (unsigned long long)vm->device_block_size);
        dev_info(&vm->vdev->dev, "memory block size: 0x%lx",
                 memory_block_size_bytes());
        if (vm->in_sbm)
@@ -2508,10 +2473,52 @@ static int virtio_mem_init(struct virtio_mem *vm)
        else
                dev_info(&vm->vdev->dev, "big block size: 0x%llx",
                         (unsigned long long)vm->bbm.bb_size);
+
+       return 0;
+}
+
+static int virtio_mem_init(struct virtio_mem *vm)
+{
+       uint16_t node_id;
+
+       if (!vm->vdev->config->get) {
+               dev_err(&vm->vdev->dev, "config access disabled\n");
+               return -EINVAL;
+       }
+
+       /*
+        * We don't want to (un)plug or reuse any memory when in kdump. The
+        * memory is still accessible (but not mapped).
+        */
+       if (is_kdump_kernel()) {
+               dev_warn(&vm->vdev->dev, "disabled in kdump kernel\n");
+               return -EBUSY;
+       }
+
+       /* Fetch all properties that can't change. */
+       virtio_cread_le(vm->vdev, struct virtio_mem_config, plugged_size,
+                       &vm->plugged_size);
+       virtio_cread_le(vm->vdev, struct virtio_mem_config, block_size,
+                       &vm->device_block_size);
+       virtio_cread_le(vm->vdev, struct virtio_mem_config, node_id,
+                       &node_id);
+       vm->nid = virtio_mem_translate_node_id(vm, node_id);
+       virtio_cread_le(vm->vdev, struct virtio_mem_config, addr, &vm->addr);
+       virtio_cread_le(vm->vdev, struct virtio_mem_config, region_size,
+                       &vm->region_size);
+
+       /* Determine the nid for the device based on the lowest address. */
+       if (vm->nid == NUMA_NO_NODE)
+               vm->nid = memory_add_physaddr_to_nid(vm->addr);
+
+       dev_info(&vm->vdev->dev, "start address: 0x%llx", vm->addr);
+       dev_info(&vm->vdev->dev, "region size: 0x%llx", vm->region_size);
+       dev_info(&vm->vdev->dev, "device block size: 0x%llx",
+                (unsigned long long)vm->device_block_size);
        if (vm->nid != NUMA_NO_NODE && IS_ENABLED(CONFIG_NUMA))
                dev_info(&vm->vdev->dev, "nid: %d", vm->nid);
 
-       return 0;
+       return virtio_mem_init_hotplug(vm);
 }
 
 static int virtio_mem_create_resource(struct virtio_mem *vm)
-- 
2.31.1