diff --git a/include/linux/virtio_9p.h b/include/linux/virtio_9p.h index 332275080083..5cf11765146b 100644 --- a/include/linux/virtio_9p.h +++ b/include/linux/virtio_9p.h @@ -5,4 +5,16 @@ #include #include +/* The feature bitmap for virtio 9P */ + +/* The mount point is specified in a config variable */ +#define VIRTIO_9P_MOUNT_TAG 0 + +struct virtio_9p_config { + /* length of the tag name */ + __u16 tag_len; + /* non-NULL terminated tag name */ + __u8 tag[0]; +} __attribute__((packed)); + #endif /* _LINUX_VIRTIO_9P_H */ diff --git a/net/9p/trans_virtio.c b/net/9p/trans_virtio.c index 0aaed4819379..026775ad391a 100644 --- a/net/9p/trans_virtio.c +++ b/net/9p/trans_virtio.c @@ -78,6 +78,12 @@ struct virtio_chan { /* Scatterlist: can be too big for stack. */ struct scatterlist sg[VIRTQUEUE_NUM]; + int tag_len; + /* + * tag name to identify a mount Non-null terminated + */ + char *tag; + struct list_head chan_list; }; @@ -224,6 +230,8 @@ p9_virtio_request(struct p9_client *client, struct p9_req_t *req) static int p9_virtio_probe(struct virtio_device *vdev) { + __u16 tag_len; + char *tag; int err; struct virtio_chan *chan; @@ -248,6 +256,23 @@ static int p9_virtio_probe(struct virtio_device *vdev) sg_init_table(chan->sg, VIRTQUEUE_NUM); chan->inuse = false; + if (virtio_has_feature(vdev, VIRTIO_9P_MOUNT_TAG)) { + vdev->config->get(vdev, + offsetof(struct virtio_9p_config, tag_len), + &tag_len, sizeof(tag_len)); + } else { + err = -EINVAL; + goto out_free_vq; + } + tag = kmalloc(tag_len, GFP_KERNEL); + if (!tag) { + err = -ENOMEM; + goto out_free_vq; + } + vdev->config->get(vdev, offsetof(struct virtio_9p_config, tag), + tag, tag_len); + chan->tag = tag; + chan->tag_len = tag_len; mutex_lock(&virtio_9p_lock); list_add_tail(&chan->chan_list, &virtio_chan_list); mutex_unlock(&virtio_9p_lock); @@ -284,7 +309,7 @@ p9_virtio_create(struct p9_client *client, const char *devname, char *args) mutex_lock(&virtio_9p_lock); list_for_each_entry(chan, &virtio_chan_list, chan_list) { - if (!strcmp(devname, dev_name(&chan->vdev->dev))) { + if (!strncmp(devname, chan->tag, chan->tag_len)) { if (!chan->inuse) { chan->inuse = true; found = 1; @@ -323,6 +348,7 @@ static void p9_virtio_remove(struct virtio_device *vdev) mutex_lock(&virtio_9p_lock); list_del(&chan->chan_list); mutex_unlock(&virtio_9p_lock); + kfree(chan->tag); kfree(chan); } @@ -332,13 +358,19 @@ static struct virtio_device_id id_table[] = { { 0 }, }; +static unsigned int features[] = { + VIRTIO_9P_MOUNT_TAG, +}; + /* The standard "struct lguest_driver": */ static struct virtio_driver p9_virtio_drv = { - .driver.name = KBUILD_MODNAME, - .driver.owner = THIS_MODULE, - .id_table = id_table, - .probe = p9_virtio_probe, - .remove = p9_virtio_remove, + .feature_table = features, + .feature_table_size = ARRAY_SIZE(features), + .driver.name = KBUILD_MODNAME, + .driver.owner = THIS_MODULE, + .id_table = id_table, + .probe = p9_virtio_probe, + .remove = p9_virtio_remove, }; static struct p9_trans_module p9_virtio_trans = {