diff options
Diffstat (limited to 'hw/virtio/virtio-pmem.c')
| -rw-r--r-- | hw/virtio/virtio-pmem.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/hw/virtio/virtio-pmem.c b/hw/virtio/virtio-pmem.c new file mode 100644 index 0000000000..adbfb603ab --- /dev/null +++ b/hw/virtio/virtio-pmem.c @@ -0,0 +1,189 @@ +/* + * Virtio PMEM device + * + * Copyright (C) 2018-2019 Red Hat, Inc. + * + * Authors: + * Pankaj Gupta <pagupta@redhat.com> + * David Hildenbrand <david@redhat.com> + * + * This work is licensed under the terms of the GNU GPL, version 2. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include "qapi/error.h" +#include "qemu-common.h" +#include "qemu/error-report.h" +#include "hw/virtio/virtio-pmem.h" +#include "hw/virtio/virtio-access.h" +#include "standard-headers/linux/virtio_ids.h" +#include "standard-headers/linux/virtio_pmem.h" +#include "block/aio.h" +#include "block/thread-pool.h" + +typedef struct VirtIODeviceRequest { + VirtQueueElement elem; + int fd; + VirtIOPMEM *pmem; + VirtIODevice *vdev; + struct virtio_pmem_req req; + struct virtio_pmem_resp resp; +} VirtIODeviceRequest; + +static int worker_cb(void *opaque) +{ + VirtIODeviceRequest *req_data = opaque; + int err = 0; + + /* flush raw backing image */ + err = fsync(req_data->fd); + if (err != 0) { + err = 1; + } + + virtio_stw_p(req_data->vdev, &req_data->resp.ret, err); + + return 0; +} + +static void done_cb(void *opaque, int ret) +{ + VirtIODeviceRequest *req_data = opaque; + int len = iov_from_buf(req_data->elem.in_sg, req_data->elem.in_num, 0, + &req_data->resp, sizeof(struct virtio_pmem_resp)); + + /* Callbacks are serialized, so no need to use atomic ops. */ + virtqueue_push(req_data->pmem->rq_vq, &req_data->elem, len); + virtio_notify((VirtIODevice *)req_data->pmem, req_data->pmem->rq_vq); + g_free(req_data); +} + +static void virtio_pmem_flush(VirtIODevice *vdev, VirtQueue *vq) +{ + VirtIODeviceRequest *req_data; + VirtIOPMEM *pmem = VIRTIO_PMEM(vdev); + HostMemoryBackend *backend = MEMORY_BACKEND(pmem->memdev); + ThreadPool *pool = aio_get_thread_pool(qemu_get_aio_context()); + + req_data = virtqueue_pop(vq, sizeof(VirtIODeviceRequest)); + if (!req_data) { + virtio_error(vdev, "virtio-pmem missing request data"); + return; + } + + if (req_data->elem.out_num < 1 || req_data->elem.in_num < 1) { + virtio_error(vdev, "virtio-pmem request not proper"); + g_free(req_data); + return; + } + req_data->fd = memory_region_get_fd(&backend->mr); + req_data->pmem = pmem; + req_data->vdev = vdev; + thread_pool_submit_aio(pool, worker_cb, req_data, done_cb, req_data); +} + +static void virtio_pmem_get_config(VirtIODevice *vdev, uint8_t *config) +{ + VirtIOPMEM *pmem = VIRTIO_PMEM(vdev); + struct virtio_pmem_config *pmemcfg = (struct virtio_pmem_config *) config; + + virtio_stq_p(vdev, &pmemcfg->start, pmem->start); + virtio_stq_p(vdev, &pmemcfg->size, memory_region_size(&pmem->memdev->mr)); +} + +static uint64_t virtio_pmem_get_features(VirtIODevice *vdev, uint64_t features, + Error **errp) +{ + return features; +} + +static void virtio_pmem_realize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIOPMEM *pmem = VIRTIO_PMEM(dev); + + if (!pmem->memdev) { + error_setg(errp, "virtio-pmem memdev not set"); + return; + } + + if (host_memory_backend_is_mapped(pmem->memdev)) { + char *path = object_get_canonical_path_component(OBJECT(pmem->memdev)); + error_setg(errp, "can't use already busy memdev: %s", path); + g_free(path); + return; + } + + host_memory_backend_set_mapped(pmem->memdev, true); + virtio_init(vdev, TYPE_VIRTIO_PMEM, VIRTIO_ID_PMEM, + sizeof(struct virtio_pmem_config)); + pmem->rq_vq = virtio_add_queue(vdev, 128, virtio_pmem_flush); +} + +static void virtio_pmem_unrealize(DeviceState *dev, Error **errp) +{ + VirtIODevice *vdev = VIRTIO_DEVICE(dev); + VirtIOPMEM *pmem = VIRTIO_PMEM(dev); + + host_memory_backend_set_mapped(pmem->memdev, false); + virtio_cleanup(vdev); +} + +static void virtio_pmem_fill_device_info(const VirtIOPMEM *pmem, + VirtioPMEMDeviceInfo *vi) +{ + vi->memaddr = pmem->start; + vi->size = pmem->memdev ? memory_region_size(&pmem->memdev->mr) : 0; + vi->memdev = object_get_canonical_path(OBJECT(pmem->memdev)); +} + +static MemoryRegion *virtio_pmem_get_memory_region(VirtIOPMEM *pmem, + Error **errp) +{ + if (!pmem->memdev) { + error_setg(errp, "'%s' property must be set", VIRTIO_PMEM_MEMDEV_PROP); + return NULL; + } + + return &pmem->memdev->mr; +} + +static Property virtio_pmem_properties[] = { + DEFINE_PROP_UINT64(VIRTIO_PMEM_ADDR_PROP, VirtIOPMEM, start, 0), + DEFINE_PROP_LINK(VIRTIO_PMEM_MEMDEV_PROP, VirtIOPMEM, memdev, + TYPE_MEMORY_BACKEND, HostMemoryBackend *), + DEFINE_PROP_END_OF_LIST(), +}; + +static void virtio_pmem_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); + VirtIOPMEMClass *vpc = VIRTIO_PMEM_CLASS(klass); + + dc->props = virtio_pmem_properties; + + vdc->realize = virtio_pmem_realize; + vdc->unrealize = virtio_pmem_unrealize; + vdc->get_config = virtio_pmem_get_config; + vdc->get_features = virtio_pmem_get_features; + + vpc->fill_device_info = virtio_pmem_fill_device_info; + vpc->get_memory_region = virtio_pmem_get_memory_region; +} + +static TypeInfo virtio_pmem_info = { + .name = TYPE_VIRTIO_PMEM, + .parent = TYPE_VIRTIO_DEVICE, + .class_size = sizeof(VirtIOPMEMClass), + .class_init = virtio_pmem_class_init, + .instance_size = sizeof(VirtIOPMEM), +}; + +static void virtio_register_types(void) +{ + type_register_static(&virtio_pmem_info); +} + +type_init(virtio_register_types) |