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 */ 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 32 static int virtio_pmem_probe(struct virtio_device *vdev) 33 { 34 struct nd_region_desc ndr_desc = {}; 35 struct nd_region *nd_region; 36 struct virtio_pmem *vpmem; 37 struct resource res; 38 int err = 0; 39 40 if (!vdev->config->get) { 41 dev_err(&vdev->dev, "%s failure: config access disabled\n", 42 __func__); 43 return -EINVAL; 44 } 45 46 vpmem = devm_kzalloc(&vdev->dev, sizeof(*vpmem), GFP_KERNEL); 47 if (!vpmem) { 48 err = -ENOMEM; 49 goto out_err; 50 } 51 52 vpmem->vdev = vdev; 53 vdev->priv = vpmem; 54 err = init_vq(vpmem); 55 if (err) { 56 dev_err(&vdev->dev, "failed to initialize virtio pmem vq's\n"); 57 goto out_err; 58 } 59 60 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, 61 start, &vpmem->start); 62 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, 63 size, &vpmem->size); 64 65 res.start = vpmem->start; 66 res.end = vpmem->start + vpmem->size - 1; 67 vpmem->nd_desc.provider_name = "virtio-pmem"; 68 vpmem->nd_desc.module = THIS_MODULE; 69 70 vpmem->nvdimm_bus = nvdimm_bus_register(&vdev->dev, 71 &vpmem->nd_desc); 72 if (!vpmem->nvdimm_bus) { 73 dev_err(&vdev->dev, "failed to register device with nvdimm_bus\n"); 74 err = -ENXIO; 75 goto out_vq; 76 } 77 78 dev_set_drvdata(&vdev->dev, vpmem->nvdimm_bus); 79 80 ndr_desc.res = &res; 81 82 ndr_desc.numa_node = memory_add_physaddr_to_nid(res.start); 83 ndr_desc.target_node = phys_to_target_node(res.start); 84 if (ndr_desc.target_node == NUMA_NO_NODE) { 85 ndr_desc.target_node = ndr_desc.numa_node; 86 dev_dbg(&vdev->dev, "changing target node from %d to %d", 87 NUMA_NO_NODE, ndr_desc.target_node); 88 } 89 90 ndr_desc.flush = async_pmem_flush; 91 ndr_desc.provider_data = vdev; 92 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); 93 set_bit(ND_REGION_ASYNC, &ndr_desc.flags); 94 /* 95 * The NVDIMM region could be available before the 96 * virtio_device_ready() that is called by 97 * virtio_dev_probe(), so we set device ready here. 98 */ 99 virtio_device_ready(vdev); 100 nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc); 101 if (!nd_region) { 102 dev_err(&vdev->dev, "failed to create nvdimm region\n"); 103 err = -ENXIO; 104 goto out_nd; 105 } 106 return 0; 107 out_nd: 108 virtio_reset_device(vdev); 109 nvdimm_bus_unregister(vpmem->nvdimm_bus); 110 out_vq: 111 vdev->config->del_vqs(vdev); 112 out_err: 113 return err; 114 } 115 116 static void virtio_pmem_remove(struct virtio_device *vdev) 117 { 118 struct nvdimm_bus *nvdimm_bus = dev_get_drvdata(&vdev->dev); 119 120 nvdimm_bus_unregister(nvdimm_bus); 121 vdev->config->del_vqs(vdev); 122 virtio_reset_device(vdev); 123 } 124 125 static struct virtio_driver virtio_pmem_driver = { 126 .driver.name = KBUILD_MODNAME, 127 .driver.owner = THIS_MODULE, 128 .id_table = id_table, 129 .probe = virtio_pmem_probe, 130 .remove = virtio_pmem_remove, 131 }; 132 133 module_virtio_driver(virtio_pmem_driver); 134 MODULE_DEVICE_TABLE(virtio, id_table); 135 MODULE_DESCRIPTION("Virtio pmem driver"); 136 MODULE_LICENSE("GPL"); 137