hw/9pfs/virtio-9p-device.c

   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
  23 static uint32_t virtio_9p_get_features(VirtIODevice *vdev, uint32_t features)
  24 {
  25     features |= 1 << VIRTIO_9P_MOUNT_TAG;
  26     return features;
  27 }
  28
  29 static V9fsState *to_virtio_9p(VirtIODevice *vdev)
  30 {
  31     return (V9fsState *)vdev;
  32 }
  33
  34 static void virtio_9p_get_config(VirtIODevice *vdev, uint8_t *config)
  35 {
  36     int len;
  37     struct virtio_9p_config *cfg;
  38     V9fsState *s = to_virtio_9p(vdev);
  39
  40     len = strlen(s->tag);
  41     cfg = g_malloc0(sizeof(struct virtio_9p_config) + len);
  42     stw_raw(&cfg->tag_len, len);
  43     /* We don't copy the terminating null to config space */
  44     memcpy(cfg->tag, s->tag, len);
  45     memcpy(config, cfg, s->config_size);
  46     g_free(cfg);
  47 }
  48
  49 static VirtIODevice *virtio_9p_common_init(DeviceState *dev, V9fsConf *conf,
  50                                            V9fsState **ps)
  51 {
  52     V9fsState *s = *ps;
  53     int i, len;
  54     struct stat stat;
  55     FsDriverEntry *fse;
  56     V9fsPath path;
  57
  58     /*
  59      * We have two cases here: the old virtio-9p-pci device, and the
  60      * refactored virtio-9p.
  61      */
  62
  63     if (s == NULL) {
  64         s = (V9fsState *)virtio_common_init("virtio-9p",
  65                                         VIRTIO_ID_9P,
  66                                         sizeof(struct virtio_9p_config)+
  67                                         MAX_TAG_LEN,
  68                                         sizeof(V9fsState));
  69     } else {
  70         virtio_init(VIRTIO_DEVICE(s), "virtio-9p", VIRTIO_ID_9P,
  71                     sizeof(struct virtio_9p_config) + MAX_TAG_LEN);
  72     }
  73     /* initialize pdu allocator */
  74     QLIST_INIT(&s->free_list);
  75     QLIST_INIT(&s->active_list);
  76     for (i = 0; i < (MAX_REQ - 1); i++) {
  77         QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
  78     }
  79
  80     s->vq = virtio_add_queue(&s->vdev, MAX_REQ, handle_9p_output);
  81
  82     fse = get_fsdev_fsentry(conf->fsdev_id);
  83
  84     if (!fse) {
  85         /* We don't have a fsdev identified by fsdev_id */
  86         fprintf(stderr, "Virtio-9p device couldn't find fsdev with the "
  87                 "id = %s\n", conf->fsdev_id ? conf->fsdev_id : "NULL");
  88         exit(1);
  89     }
  90
  91     if (!conf->tag) {
  92         /* we haven't specified a mount_tag */
  93         fprintf(stderr, "fsdev with id %s needs mount_tag arguments\n",
  94                 conf->fsdev_id);
  95         exit(1);
  96     }
  97
  98     s->ctx.export_flags = fse->export_flags;
  99     s->ctx.fs_root = g_strdup(fse->path);
 100     s->ctx.exops.get_st_gen = NULL;
 101     len = strlen(conf->tag);
 102     if (len > MAX_TAG_LEN - 1) {
 103         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "
 104                 "maximum (%d bytes)", conf->tag, len, MAX_TAG_LEN - 1);
 105         exit(1);
 106     }
 107
 108     s->tag = g_strdup(conf->tag);
 109     s->ctx.uid = -1;
 110
 111     s->ops = fse->ops;
 112     s->vdev.get_features = virtio_9p_get_features;
 113     s->config_size = sizeof(struct virtio_9p_config) + len;
 114     s->vdev.get_config = virtio_9p_get_config;
 115     s->fid_list = NULL;
 116     qemu_co_rwlock_init(&s->rename_lock);
 117
 118     if (s->ops->init(&s->ctx) < 0) {
 119         fprintf(stderr, "Virtio-9p Failed to initialize fs-driver with id:%s"
 120                 " and export path:%s\n", conf->fsdev_id, s->ctx.fs_root);
 121         exit(1);
 122     }
 123     if (v9fs_init_worker_threads() < 0) {
 124         fprintf(stderr, "worker thread initialization failed\n");
 125         exit(1);
 126     }
 127
 128     /*
 129      * Check details of export path, We need to use fs driver
 130      * call back to do that. Since we are in the init path, we don't
 131      * use co-routines here.
 132      */
 133     v9fs_path_init(&path);
 134     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
 135         fprintf(stderr,
 136                 "error in converting name to path %s", strerror(errno));
 137         exit(1);
 138     }
 139     if (s->ops->lstat(&s->ctx, &path, &stat)) {
 140         fprintf(stderr, "share path %s does not exist\n", fse->path);
 141         exit(1);
 142     } else if (!S_ISDIR(stat.st_mode)) {
 143         fprintf(stderr, "share path %s is not a directory\n", fse->path);
 144         exit(1);
 145     }
 146     v9fs_path_free(&path);
 147
 148     return &s->vdev;
 149 }
 150
 151 VirtIODevice *virtio_9p_init(DeviceState *dev, V9fsConf *conf)
 152 {
 153     V9fsState *s = NULL;
 154     return virtio_9p_common_init(dev, conf, &s);
 155 }
 156
 157 /* virtio-9p device */
 158
 159 static int virtio_9p_device_init(VirtIODevice *vdev)
 160 {
 161     DeviceState *qdev = DEVICE(vdev);
 162     V9fsState *s = VIRTIO_9P(vdev);
 163     V9fsConf *fsconf = &(s->fsconf);
 164     if (virtio_9p_common_init(qdev, fsconf, &s) == NULL) {
 165         return -1;
 166     }
 167     return 0;
 168 }
 169
 170 static Property virtio_9p_properties[] = {
 171     DEFINE_VIRTIO_9P_PROPERTIES(V9fsState, fsconf),
 172     DEFINE_PROP_END_OF_LIST(),
 173 };
 174
 175 static void virtio_9p_class_init(ObjectClass *klass, void *data)
 176 {
 177     DeviceClass *dc = DEVICE_CLASS(klass);
 178     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 179     dc->props = virtio_9p_properties;
 180     vdc->init = virtio_9p_device_init;
 181     vdc->get_features = virtio_9p_get_features;
 182     vdc->get_config = virtio_9p_get_config;
 183 }
 184
 185 static const TypeInfo virtio_device_info = {
 186     .name = TYPE_VIRTIO_9P,
 187     .parent = TYPE_VIRTIO_DEVICE,
 188     .instance_size = sizeof(V9fsState),
 189     .class_init = virtio_9p_class_init,
 190 };
 191
 192 static void virtio_9p_register_types(void)
 193 {
 194     type_register_static(&virtio_device_info);
 195 }
 196
 197 type_init(virtio_9p_register_types)