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 #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_device_realize(DeviceState *dev, Error **errp)
  47 {
  48     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
  49     V9fsState *s = VIRTIO_9P(dev);
  50     int i, len;
  51     struct stat stat;
  52     FsDriverEntry *fse;
  53     V9fsPath path;
  54
  55     virtio_init(vdev, "virtio-9p", VIRTIO_ID_9P,
  56                 sizeof(struct virtio_9p_config) + MAX_TAG_LEN);
  57
  58     /* initialize pdu allocator */
  59     QLIST_INIT(&s->free_list);
  60     QLIST_INIT(&s->active_list);
  61     for (i = 0; i < (MAX_REQ - 1); i++) {
  62         QLIST_INSERT_HEAD(&s->free_list, &s->pdus[i], next);
  63     }
  64
  65     s->vq = virtio_add_queue(vdev, MAX_REQ, handle_9p_output);
  66
  67     v9fs_path_init(&path);
  68
  69     fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
  70
  71     if (!fse) {
  72         /* We don't have a fsdev identified by fsdev_id */
  73         error_setg(errp, "Virtio-9p device couldn't find fsdev with the "
  74                    "id = %s",
  75                    s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL");
  76         goto out;
  77     }
  78
  79     if (!s->fsconf.tag) {
  80         /* we haven't specified a mount_tag */
  81         error_setg(errp, "fsdev with id %s needs mount_tag arguments",
  82                    s->fsconf.fsdev_id);
  83         goto out;
  84     }
  85
  86     s->ctx.export_flags = fse->export_flags;
  87     s->ctx.fs_root = g_strdup(fse->path);
  88     s->ctx.exops.get_st_gen = NULL;
  89     len = strlen(s->fsconf.tag);
  90     if (len > MAX_TAG_LEN - 1) {
  91         error_setg(errp, "mount tag '%s' (%d bytes) is longer than "
  92                    "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1);
  93         goto out;
  94     }
  95
  96     s->tag = g_strdup(s->fsconf.tag);
  97     s->ctx.uid = -1;
  98
  99     s->ops = fse->ops;
 100     s->config_size = sizeof(struct virtio_9p_config) + len;
 101     s->fid_list = NULL;
 102     qemu_co_rwlock_init(&s->rename_lock);
 103
 104     if (s->ops->init(&s->ctx) < 0) {
 105         error_setg(errp, "Virtio-9p Failed to initialize fs-driver with id:%s"
 106                    " and export path:%s", s->fsconf.fsdev_id, s->ctx.fs_root);
 107         goto out;
 108     }
 109     if (v9fs_init_worker_threads() < 0) {
 110         error_setg(errp, "worker thread initialization failed");
 111         goto out;
 112     }
 113
 114     /*
 115      * Check details of export path, We need to use fs driver
 116      * call back to do that. Since we are in the init path, we don't
 117      * use co-routines here.
 118      */
 119     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
 120         error_setg(errp,
 121                    "error in converting name to path %s", strerror(errno));
 122         goto out;
 123     }
 124     if (s->ops->lstat(&s->ctx, &path, &stat)) {
 125         error_setg(errp, "share path %s does not exist", fse->path);
 126         goto out;
 127     } else if (!S_ISDIR(stat.st_mode)) {
 128         error_setg(errp, "share path %s is not a directory", fse->path);
 129         goto out;
 130     }
 131     v9fs_path_free(&path);
 132
 133     return;
 134 out:
 135     g_free(s->ctx.fs_root);
 136     g_free(s->tag);
 137     virtio_cleanup(vdev);
 138     v9fs_path_free(&path);
 139 }
 140
 141 /* virtio-9p device */
 142
 143 static Property virtio_9p_properties[] = {
 144     DEFINE_PROP_STRING("mount_tag", V9fsState, fsconf.tag),
 145     DEFINE_PROP_STRING("fsdev", V9fsState, fsconf.fsdev_id),
 146     DEFINE_PROP_END_OF_LIST(),
 147 };
 148
 149 static void virtio_9p_class_init(ObjectClass *klass, void *data)
 150 {
 151     DeviceClass *dc = DEVICE_CLASS(klass);
 152     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 153
 154     dc->props = virtio_9p_properties;
 155     set_bit(DEVICE_CATEGORY_STORAGE, dc->categories);
 156     vdc->realize = virtio_9p_device_realize;
 157     vdc->get_features = virtio_9p_get_features;
 158     vdc->get_config = virtio_9p_get_config;
 159 }
 160
 161 static const TypeInfo virtio_device_info = {
 162     .name = TYPE_VIRTIO_9P,
 163     .parent = TYPE_VIRTIO_DEVICE,
 164     .instance_size = sizeof(V9fsState),
 165     .class_init = virtio_9p_class_init,
 166 };
 167
 168 static void virtio_9p_register_types(void)
 169 {
 170     type_register_static(&virtio_device_info);
 171 }
 172
 173 type_init(virtio_9p_register_types)