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     fse = get_fsdev_fsentry(s->fsconf.fsdev_id);
  65
  66     if (!fse) {
  67         /* We don't have a fsdev identified by fsdev_id */
  68         fprintf(stderr, "Virtio-9p device couldn't find fsdev with the "
  69                 "id = %s\n",
  70                 s->fsconf.fsdev_id ? s->fsconf.fsdev_id : "NULL");
  71         return -1;
  72     }
  73
  74     if (!s->fsconf.tag) {
  75         /* we haven't specified a mount_tag */
  76         fprintf(stderr, "fsdev with id %s needs mount_tag arguments\n",
  77                 s->fsconf.fsdev_id);
  78         return -1;
  79     }
  80
  81     s->ctx.export_flags = fse->export_flags;
  82     s->ctx.fs_root = g_strdup(fse->path);
  83     s->ctx.exops.get_st_gen = NULL;
  84     len = strlen(s->fsconf.tag);
  85     if (len > MAX_TAG_LEN - 1) {
  86         fprintf(stderr, "mount tag '%s' (%d bytes) is longer than "
  87                 "maximum (%d bytes)", s->fsconf.tag, len, MAX_TAG_LEN - 1);
  88         return -1;
  89     }
  90
  91     s->tag = strdup(s->fsconf.tag);
  92     s->ctx.uid = -1;
  93
  94     s->ops = fse->ops;
  95     s->config_size = sizeof(struct virtio_9p_config) + len;
  96     s->fid_list = NULL;
  97     qemu_co_rwlock_init(&s->rename_lock);
  98
  99     if (s->ops->init(&s->ctx) < 0) {
 100         fprintf(stderr, "Virtio-9p Failed to initialize fs-driver with id:%s"
 101                 " and export path:%s\n", s->fsconf.fsdev_id, s->ctx.fs_root);
 102         return -1;
 103     }
 104     if (v9fs_init_worker_threads() < 0) {
 105         fprintf(stderr, "worker thread initialization failed\n");
 106         return -1;
 107     }
 108
 109     /*
 110      * Check details of export path, We need to use fs driver
 111      * call back to do that. Since we are in the init path, we don't
 112      * use co-routines here.
 113      */
 114     v9fs_path_init(&path);
 115     if (s->ops->name_to_path(&s->ctx, NULL, "/", &path) < 0) {
 116         fprintf(stderr,
 117                 "error in converting name to path %s", strerror(errno));
 118         return -1;
 119     }
 120     if (s->ops->lstat(&s->ctx, &path, &stat)) {
 121         fprintf(stderr, "share path %s does not exist\n", fse->path);
 122         return -1;
 123     } else if (!S_ISDIR(stat.st_mode)) {
 124         fprintf(stderr, "share path %s is not a directory\n", fse->path);
 125         return -1;
 126     }
 127     v9fs_path_free(&path);
 128
 129     return 0;
 130 }
 131
 132 /* virtio-9p device */
 133
 134 static Property virtio_9p_properties[] = {
 135     DEFINE_VIRTIO_9P_PROPERTIES(V9fsState, fsconf),
 136     DEFINE_PROP_END_OF_LIST(),
 137 };
 138
 139 static void virtio_9p_class_init(ObjectClass *klass, void *data)
 140 {
 141     DeviceClass *dc = DEVICE_CLASS(klass);
 142     VirtioDeviceClass *vdc = VIRTIO_DEVICE_CLASS(klass);
 143     dc->props = virtio_9p_properties;
 144     vdc->init = virtio_9p_device_init;
 145     vdc->get_features = virtio_9p_get_features;
 146     vdc->get_config = virtio_9p_get_config;
 147 }
 148
 149 static const TypeInfo virtio_device_info = {
 150     .name = TYPE_VIRTIO_9P,
 151     .parent = TYPE_VIRTIO_DEVICE,
 152     .instance_size = sizeof(V9fsState),
 153     .class_init = virtio_9p_class_init,
 154 };
 155
 156 static void virtio_9p_register_types(void)
 157 {
 158     type_register_static(&virtio_device_info);
 159 }
 160
 161 type_init(virtio_9p_register_types)