1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * virtio_pmem.c: Virtio pmem Driver
4 *
5 * Discovers persistent memory range information
6 * from host and registers the virtual pmem device
7 * with libnvdimm core.
8 */
9 #include "virtio_pmem.h"
10 #include "nd.h"
11
12 static struct virtio_device_id id_table[] = {
13 { VIRTIO_ID_PMEM, VIRTIO_DEV_ANY_ID },
14 { 0 },
15 };
16
17 /* Initialize virt queue */
init_vq(struct virtio_pmem * vpmem)18 static int init_vq(struct virtio_pmem *vpmem)
19 {
20 /* single vq */
21 vpmem->req_vq = virtio_find_single_vq(vpmem->vdev,
22 virtio_pmem_host_ack, "flush_queue");
23 if (IS_ERR(vpmem->req_vq))
24 return PTR_ERR(vpmem->req_vq);
25
26 spin_lock_init(&vpmem->pmem_lock);
27 INIT_LIST_HEAD(&vpmem->req_list);
28
29 return 0;
30 };
31
virtio_pmem_probe(struct virtio_device * vdev)32 static int virtio_pmem_probe(struct virtio_device *vdev)
33 {
34 struct nd_region_desc ndr_desc = {};
35 int nid = dev_to_node(&vdev->dev);
36 struct nd_region *nd_region;
37 struct virtio_pmem *vpmem;
38 struct resource res;
39 int err = 0;
40
41 if (!vdev->config->get) {
42 dev_err(&vdev->dev, "%s failure: config access disabled\n",
43 __func__);
44 return -EINVAL;
45 }
46
47 vpmem = devm_kzalloc(&vdev->dev, sizeof(*vpmem), GFP_KERNEL);
48 if (!vpmem) {
49 err = -ENOMEM;
50 goto out_err;
51 }
52
53 vpmem->vdev = vdev;
54 vdev->priv = vpmem;
55 err = init_vq(vpmem);
56 if (err) {
57 dev_err(&vdev->dev, "failed to initialize virtio pmem vq's\n");
58 goto out_err;
59 }
60
61 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config,
62 start, &vpmem->start);
63 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config,
64 size, &vpmem->size);
65
66 res.start = vpmem->start;
67 res.end = vpmem->start + vpmem->size - 1;
68 vpmem->nd_desc.provider_name = "virtio-pmem";
69 vpmem->nd_desc.module = THIS_MODULE;
70
71 vpmem->nvdimm_bus = nvdimm_bus_register(&vdev->dev,
72 &vpmem->nd_desc);
73 if (!vpmem->nvdimm_bus) {
74 dev_err(&vdev->dev, "failed to register device with nvdimm_bus\n");
75 err = -ENXIO;
76 goto out_vq;
77 }
78
79 dev_set_drvdata(&vdev->dev, vpmem->nvdimm_bus);
80
81 ndr_desc.res = &res;
82 ndr_desc.numa_node = nid;
83 ndr_desc.flush = async_pmem_flush;
84 ndr_desc.provider_data = vdev;
85 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags);
86 set_bit(ND_REGION_ASYNC, &ndr_desc.flags);
87 /*
88 * The NVDIMM region could be available before the
89 * virtio_device_ready() that is called by
90 * virtio_dev_probe(), so we set device ready here.
91 */
92 virtio_device_ready(vdev);
93 nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc);
94 if (!nd_region) {
95 dev_err(&vdev->dev, "failed to create nvdimm region\n");
96 err = -ENXIO;
97 goto out_nd;
98 }
99 return 0;
100 out_nd:
101 virtio_reset_device(vdev);
102 nvdimm_bus_unregister(vpmem->nvdimm_bus);
103 out_vq:
104 vdev->config->del_vqs(vdev);
105 out_err:
106 return err;
107 }
108
virtio_pmem_remove(struct virtio_device * vdev)109 static void virtio_pmem_remove(struct virtio_device *vdev)
110 {
111 struct nvdimm_bus *nvdimm_bus = dev_get_drvdata(&vdev->dev);
112
113 nvdimm_bus_unregister(nvdimm_bus);
114 vdev->config->del_vqs(vdev);
115 virtio_reset_device(vdev);
116 }
117
118 static struct virtio_driver virtio_pmem_driver = {
119 .driver.name = KBUILD_MODNAME,
120 .driver.owner = THIS_MODULE,
121 .id_table = id_table,
122 .probe = virtio_pmem_probe,
123 .remove = virtio_pmem_remove,
124 };
125
126 module_virtio_driver(virtio_pmem_driver);
127 MODULE_DEVICE_TABLE(virtio, id_table);
128 MODULE_DESCRIPTION("Virtio pmem driver");
129 MODULE_LICENSE("GPL");
130
