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 int err; 21 22 /* single vq */ 23 vpmem->req_vq = virtio_find_single_vq(vpmem->vdev, 24 virtio_pmem_host_ack, "flush_queue"); 25 if (IS_ERR(vpmem->req_vq)) { 26 err = PTR_ERR(vpmem->req_vq); 27 vpmem->req_vq = NULL; 28 return err; 29 } 30 31 spin_lock_init(&vpmem->pmem_lock); 32 INIT_LIST_HEAD(&vpmem->req_list); 33 vpmem->req_inflight = NULL; 34 WRITE_ONCE(vpmem->broken, false); 35 36 return 0; 37 }; 38 39 static void virtio_pmem_del_vqs(struct virtio_pmem *vpmem) 40 { 41 if (!vpmem->req_vq) 42 return; 43 44 vpmem->vdev->config->del_vqs(vpmem->vdev); 45 vpmem->req_vq = NULL; 46 } 47 48 static int virtio_pmem_validate(struct virtio_device *vdev) 49 { 50 struct virtio_shm_region shm_reg; 51 52 if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION) && 53 !virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID) 54 ) { 55 dev_notice(&vdev->dev, "failed to get shared memory region %d\n", 56 VIRTIO_PMEM_SHMEM_REGION_ID); 57 __virtio_clear_bit(vdev, VIRTIO_PMEM_F_SHMEM_REGION); 58 } 59 return 0; 60 } 61 62 static int virtio_pmem_probe(struct virtio_device *vdev) 63 { 64 struct nd_region_desc ndr_desc = {}; 65 struct nd_region *nd_region; 66 struct virtio_pmem *vpmem; 67 struct resource res; 68 struct virtio_shm_region shm_reg; 69 int err = 0; 70 71 if (!vdev->config->get) { 72 dev_err(&vdev->dev, "%s failure: config access disabled\n", 73 __func__); 74 return -EINVAL; 75 } 76 77 vpmem = devm_kzalloc(&vdev->dev, sizeof(*vpmem), GFP_KERNEL); 78 if (!vpmem) { 79 err = -ENOMEM; 80 goto out_err; 81 } 82 83 mutex_init(&vpmem->flush_lock); 84 vpmem->vdev = vdev; 85 vdev->priv = vpmem; 86 vpmem->flush_wq = alloc_ordered_workqueue("virtio-pmem-flush", 87 WQ_MEM_RECLAIM); 88 if (!vpmem->flush_wq) { 89 err = -ENOMEM; 90 goto out_err; 91 } 92 93 err = init_vq(vpmem); 94 if (err) { 95 dev_err(&vdev->dev, "failed to initialize virtio pmem vq's\n"); 96 goto out_wq; 97 } 98 99 if (virtio_has_feature(vdev, VIRTIO_PMEM_F_SHMEM_REGION)) { 100 virtio_get_shm_region(vdev, &shm_reg, (u8)VIRTIO_PMEM_SHMEM_REGION_ID); 101 vpmem->start = shm_reg.addr; 102 vpmem->size = shm_reg.len; 103 } else { 104 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, 105 start, &vpmem->start); 106 virtio_cread_le(vpmem->vdev, struct virtio_pmem_config, 107 size, &vpmem->size); 108 } 109 110 res.start = vpmem->start; 111 res.end = vpmem->start + vpmem->size - 1; 112 vpmem->nd_desc.provider_name = "virtio-pmem"; 113 vpmem->nd_desc.module = THIS_MODULE; 114 115 vpmem->nvdimm_bus = nvdimm_bus_register(&vdev->dev, 116 &vpmem->nd_desc); 117 if (!vpmem->nvdimm_bus) { 118 dev_err(&vdev->dev, "failed to register device with nvdimm_bus\n"); 119 err = -ENXIO; 120 goto out_vq; 121 } 122 123 dev_set_drvdata(&vdev->dev, vpmem->nvdimm_bus); 124 125 ndr_desc.res = &res; 126 127 ndr_desc.numa_node = memory_add_physaddr_to_nid(res.start); 128 ndr_desc.target_node = phys_to_target_node(res.start); 129 if (ndr_desc.target_node == NUMA_NO_NODE) { 130 ndr_desc.target_node = ndr_desc.numa_node; 131 dev_dbg(&vdev->dev, "changing target node from %d to %d", 132 NUMA_NO_NODE, ndr_desc.target_node); 133 } 134 135 ndr_desc.flush = async_pmem_flush; 136 ndr_desc.provider_data = vdev; 137 set_bit(ND_REGION_PAGEMAP, &ndr_desc.flags); 138 set_bit(ND_REGION_ASYNC, &ndr_desc.flags); 139 /* 140 * The NVDIMM region could be available before the 141 * virtio_device_ready() that is called by 142 * virtio_dev_probe(), so we set device ready here. 143 */ 144 virtio_device_ready(vdev); 145 nd_region = nvdimm_pmem_region_create(vpmem->nvdimm_bus, &ndr_desc); 146 if (!nd_region) { 147 dev_err(&vdev->dev, "failed to create nvdimm region\n"); 148 err = -ENXIO; 149 goto out_nd; 150 } 151 return 0; 152 out_nd: 153 virtio_reset_device(vdev); 154 nvdimm_bus_unregister(vpmem->nvdimm_bus); 155 out_vq: 156 virtio_pmem_del_vqs(vpmem); 157 out_wq: 158 destroy_workqueue(vpmem->flush_wq); 159 out_err: 160 return err; 161 } 162 163 static void virtio_pmem_remove(struct virtio_device *vdev) 164 { 165 struct nvdimm_bus *nvdimm_bus = dev_get_drvdata(&vdev->dev); 166 struct virtio_pmem *vpmem = vdev->priv; 167 unsigned long flags; 168 169 spin_lock_irqsave(&vpmem->pmem_lock, flags); 170 virtio_pmem_mark_broken(vpmem); 171 spin_unlock_irqrestore(&vpmem->pmem_lock, flags); 172 173 drain_workqueue(vpmem->flush_wq); 174 virtio_reset_device(vdev); 175 176 spin_lock_irqsave(&vpmem->pmem_lock, flags); 177 virtio_pmem_drain(vpmem); 178 spin_unlock_irqrestore(&vpmem->pmem_lock, flags); 179 180 nvdimm_bus_unregister(nvdimm_bus); 181 virtio_pmem_del_vqs(vpmem); 182 destroy_workqueue(vpmem->flush_wq); 183 } 184 185 static int virtio_pmem_freeze(struct virtio_device *vdev) 186 { 187 struct virtio_pmem *vpmem = vdev->priv; 188 unsigned long flags; 189 190 spin_lock_irqsave(&vpmem->pmem_lock, flags); 191 virtio_pmem_mark_broken(vpmem); 192 spin_unlock_irqrestore(&vpmem->pmem_lock, flags); 193 194 drain_workqueue(vpmem->flush_wq); 195 virtio_reset_device(vdev); 196 197 spin_lock_irqsave(&vpmem->pmem_lock, flags); 198 virtio_pmem_drain(vpmem); 199 spin_unlock_irqrestore(&vpmem->pmem_lock, flags); 200 201 virtio_pmem_del_vqs(vpmem); 202 203 return 0; 204 } 205 206 static int virtio_pmem_restore(struct virtio_device *vdev) 207 { 208 int ret; 209 210 ret = init_vq(vdev->priv); 211 if (ret) { 212 dev_err(&vdev->dev, "failed to initialize virtio pmem's vq\n"); 213 return ret; 214 } 215 virtio_device_ready(vdev); 216 217 return 0; 218 } 219 220 static unsigned int features[] = { 221 VIRTIO_PMEM_F_SHMEM_REGION, 222 }; 223 224 static struct virtio_driver virtio_pmem_driver = { 225 .feature_table = features, 226 .feature_table_size = ARRAY_SIZE(features), 227 .driver.name = KBUILD_MODNAME, 228 .id_table = id_table, 229 .validate = virtio_pmem_validate, 230 .probe = virtio_pmem_probe, 231 .remove = virtio_pmem_remove, 232 .freeze = virtio_pmem_freeze, 233 .restore = virtio_pmem_restore, 234 }; 235 236 module_virtio_driver(virtio_pmem_driver); 237 MODULE_DEVICE_TABLE(virtio, id_table); 238 MODULE_DESCRIPTION("Virtio pmem driver"); 239 MODULE_LICENSE("GPL"); 240