[PATCH v1 5/8] virtio-mem: factor out hotplug specifics from virtio_mem_init() into virtio_mem_init_hotplug()

From: David Hildenbrand
Date: Tue Sep 28 2021 - 14:24:34 EST


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