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