1 /* 2 * Virtio 9p backend 3 * 4 * Copyright IBM, Corp. 2010 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #include "hw/virtio/virtio.h" 15 #include "hw/virtio/virtio-9p.h" 16 #include "hw/i386/pc.h" 17 #include "qemu/sockets.h" 18 #include "virtio-9p.h" 19 #include "fsdev/qemu-fsdev.h" 20 #include "virtio-9p-xattr.h" 21 #include "virtio-9p-coth.h" 22 #include "hw/virtio/virtio-access.h" 23 24 static uint64_t virtio_9p_get_features(VirtIODevice *vdev, uint64_t features, 25 Error **errp) 26 { 27 virtio_add_feature(&features, VIRTIO_9P_MOUNT_TAG); 28 return features; 29 } 30 31 static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config) 32 { 33 int len; 34 struct virtio_9p_config *cfg; 35 V9fsState *s = VIRTIO_9P(vdev); 36 37 len = strlen(s->tag); 38 cfg = g_malloc0(sizeof(struct virtio_9p_config) + len); 39 virtio_stw_p(vdev, &cfg->tag_len, len); 40 /* We don't copy the terminating null to config space */ 41 memcpy(cfg->tag, s->tag, len); 42 memcpy(config, cfg, s->config_size); 43 g_free(cfg); 44 } 45 46 static void virtio_9p_save(QEMUFile *f, void *opaque) 47 { 48 virtio_save(VIRTIO_DEVICE(opaque), f); 49 } 50 51 static int virtio_9p_load(QEMUFile *f, void *opaque, int version_id) 52 { 53 return virtio_load(VIRTIO_DEVICE(opaque), f, version_id); 54 } 55 56 static void virtio_9p_device_realize(DeviceState *dev, Error **errp) 57 { 58 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 59 V9fsState *s = VIRTIO_9P(dev); 60 int i, len; 61 struct stat stat; 62 FsDriverEntry *fse; 63 V9fsPath path; 64 65 virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P, 66 sizeof(struct virtio_9p_config) + MAX_TAG_LEN); 67 68 /* initialize pdu allocator */ 69 QLIST_INIT(&s->free_list); 70 QLIST_INIT(&s->active_list); 71 for (i = 0; i < (MAX_REQ - 1); i++) { 72 QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next); 73 } 74 75 s->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output); 76 77 v9fs_path_init(&path); 78 79 fse = get_fsdev_fsentry(s->fsconf.fsdev_id); 80 81 if (!fse) { 82 /* We don't have a fsdev identified by fsdev_id */ 83 error_setg(errp, "Virtio-9p device couldn't find fsdev with the " 84 "id = %s", 85 s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL"); 86 goto out; 87 } 88 89 if (!s->fsconf.tag) { 90 /* we haven't specified a mount_tag */ 91 error_setg(errp, "fsdev with id %s needs mount_tag arguments", 92 s->fsconf.fsdev_id); 93 goto out; 94 } 95 96 s->ctx.export_flags = fse->export_flags; 97 s->ctx.fs_root = g_strdup(fse->path); 98 s->ctx.exops.get_st_gen = NULL; 99 len = strlen(s->fsconf.tag); 100 if (len > MAX_TAG_LEN - 1) { 101 error_setg(errp, "mount tag '%s' (%d bytes) is longer than " 102 "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1); 103 goto out; 104 } 105 106 s->tag = g_strdup(s->fsconf.tag); 107 s->ctx.uid = -1; 108 109 s->ops = fse->ops; 110 s->config_size = sizeof(struct virtio_9p_config) + len; 111 s->fid_list = NULL; 112 qemu_co_rwlock_init(&s->rename_lock); 113 114 if (s->ops->init(&s->ctx) < 0) { 115 error_setg(errp, "Virtio-9p Failed to initialize fs-driver with id:%s" 116 " and export path:%s", s->fsconf.fsdev_id, s->ctx.fs_root); 117 goto out; 118 } 119 120 /* 121 * Check details of export path, We need to use fs driver 122 * call back to do that. Since we are in the init path, we don't 123 * use co-routines here. 124 */ 125 if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) { 126 error_setg(errp, 127 "error in converting name to path %s", strerror(errno)); 128 goto out; 129 } 130 if (s->ops->lstat(&s->ctx, &path, &stat)) { 131 error_setg(errp, "share path %s does not exist", fse->path); 132 goto out; 133 } else if (!S_ISDIR(stat.st_mode)) { 134 error_setg(errp, "share path %s is not a directory", fse->path); 135 goto out; 136 } 137 v9fs_path_free(&path); 138 139 register_savevm(dev, "virtio-9p", -1, 1, virtio_9p_save, virtio_9p_load, s); 140 return; 141 out: 142 g_free(s->ctx.fs_root); 143 g_free(s->tag); 144 virtio_cleanup(vdev); 145 v9fs_path_free(&path); 146 } 147 148 static void virtio_9p_device_unrealize(DeviceState *dev, Error **errp) 149 { 150 VirtIODevice *vdev = VIRTIO_DEVICE(dev); 151 V9fsState *s = VIRTIO_9P(dev); 152 153 virtio_cleanup(vdev); 154 unregister_savevm(dev, "virtio-9p", s); 155 g_free(s->ctx.fs_root); 156 g_free(s->tag); 157 } 158 159 /* virtio-9p device */ 160 161 static Property virtio_9p_properties[] = { 162 DEFINE_PROP_STRING("mount_tag", V9fsState, fsconf.tag), 163 DEFINE_PROP_STRING("fsdev", V9fsState, fsconf.fsdev_id), 164 DEFINE_PROP_END_OF_LIST(), 165 }; 166 167 static void virtio_9p_class_init(ObjectClass *klass, void *data) 168 { 169 DeviceClass *dc = DEVICE_CLASS(klass); 170 VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass); 171 172 dc->props = virtio_9p_properties; 173 set_bit(DEVICE_CATEGORY_STORAGE, dc->categories); 174 vdc->realize = virtio_9p_device_realize; 175 vdc->unrealize = virtio_9p_device_unrealize; 176 vdc->get_features = virtio_9p_get_features; 177 vdc->get_config = virtio_9p_get_config; 178 } 179 180 static const TypeInfo virtio_device_info = { 181 .name = TYPE_VIRTIO_9P, 182 .parent = TYPE_VIRTIO_DEVICE, 183 .instance_size = sizeof(V9fsState), 184 .class_init = virtio_9p_class_init, 185 }; 186 187 static void virtio_9p_register_types(void) 188 { 189 type_register_static(&virtio_device_info); 190 } 191 192 type_init(virtio_9p_register_types) 193