| /* |
| * The Virtio 9p transport driver |
| * |
| * This is a block based transport driver based on the lguest block driver |
| * code. |
| * |
| * Copyright (C) 2007, 2008 Eric Van Hensbergen, IBM Corporation |
| * |
| * Based on virtio console driver |
| * Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 |
| * as published by the Free Software Foundation. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to: |
| * Free Software Foundation |
| * 51 Franklin Street, Fifth Floor |
| * Boston, MA 02111-1301 USA |
| * |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/in.h> |
| #include <linux/module.h> |
| #include <linux/net.h> |
| #include <linux/ipv6.h> |
| #include <linux/errno.h> |
| #include <linux/kernel.h> |
| #include <linux/un.h> |
| #include <linux/uaccess.h> |
| #include <linux/inet.h> |
| #include <linux/idr.h> |
| #include <linux/file.h> |
| #include <linux/highmem.h> |
| #include <linux/slab.h> |
| #include <net/9p/9p.h> |
| #include <linux/parser.h> |
| #include <net/9p/client.h> |
| #include <net/9p/transport.h> |
| #include <linux/scatterlist.h> |
| #include <linux/swap.h> |
| #include <linux/virtio.h> |
| #include <linux/virtio_9p.h> |
| #include "trans_common.h" |
| |
| #define VIRTQUEUE_NUM 128 |
| |
| /* a single mutex to manage channel initialization and attachment */ |
| static DEFINE_MUTEX(virtio_9p_lock); |
| static DECLARE_WAIT_QUEUE_HEAD(vp_wq); |
| static atomic_t vp_pinned = ATOMIC_INIT(0); |
| |
| /** |
| * struct virtio_chan - per-instance transport information |
| * @initialized: whether the channel is initialized |
| * @inuse: whether the channel is in use |
| * @lock: protects multiple elements within this structure |
| * @client: client instance |
| * @vdev: virtio dev associated with this channel |
| * @vq: virtio queue associated with this channel |
| * @sg: scatter gather list which is used to pack a request (protected?) |
| * |
| * We keep all per-channel information in a structure. |
| * This structure is allocated within the devices dev->mem space. |
| * A pointer to the structure will get put in the transport private. |
| * |
| */ |
| |
| struct virtio_chan { |
| bool inuse; |
| |
| spinlock_t lock; |
| |
| struct p9_client *client; |
| struct virtio_device *vdev; |
| struct virtqueue *vq; |
| int ring_bufs_avail; |
| wait_queue_head_t *vc_wq; |
| /* This is global limit. Since we don't have a global structure, |
| * will be placing it in each channel. |
| */ |
| unsigned long p9_max_pages; |
| /* 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; |
| }; |
| |
| static struct list_head virtio_chan_list; |
| |
| /* How many bytes left in this page. */ |
| static unsigned int rest_of_page(void *data) |
| { |
| return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE); |
| } |
| |
| /** |
| * p9_virtio_close - reclaim resources of a channel |
| * @client: client instance |
| * |
| * This reclaims a channel by freeing its resources and |
| * reseting its inuse flag. |
| * |
| */ |
| |
| static void p9_virtio_close(struct p9_client *client) |
| { |
| struct virtio_chan *chan = client->trans; |
| |
| mutex_lock(&virtio_9p_lock); |
| if (chan) |
| chan->inuse = false; |
| mutex_unlock(&virtio_9p_lock); |
| } |
| |
| /** |
| * req_done - callback which signals activity from the server |
| * @vq: virtio queue activity was received on |
| * |
| * This notifies us that the server has triggered some activity |
| * on the virtio channel - most likely a response to request we |
| * sent. Figure out which requests now have responses and wake up |
| * those threads. |
| * |
| * Bugs: could do with some additional sanity checking, but appears to work. |
| * |
| */ |
| |
| static void req_done(struct virtqueue *vq) |
| { |
| struct virtio_chan *chan = vq->vdev->priv; |
| struct p9_fcall *rc; |
| unsigned int len; |
| struct p9_req_t *req; |
| unsigned long flags; |
| |
| p9_debug(P9_DEBUG_TRANS, ": request done\n"); |
| |
| while (1) { |
| spin_lock_irqsave(&chan->lock, flags); |
| rc = virtqueue_get_buf(chan->vq, &len); |
| if (rc == NULL) { |
| spin_unlock_irqrestore(&chan->lock, flags); |
| break; |
| } |
| chan->ring_bufs_avail = 1; |
| spin_unlock_irqrestore(&chan->lock, flags); |
| /* Wakeup if anyone waiting for VirtIO ring space. */ |
| wake_up(chan->vc_wq); |
| p9_debug(P9_DEBUG_TRANS, ": rc %p\n", rc); |
| p9_debug(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag); |
| req = p9_tag_lookup(chan->client, rc->tag); |
| req->status = REQ_STATUS_RCVD; |
| p9_client_cb(chan->client, req); |
| } |
| } |
| |
| /** |
| * pack_sg_list - pack a scatter gather list from a linear buffer |
| * @sg: scatter/gather list to pack into |
| * @start: which segment of the sg_list to start at |
| * @limit: maximum segment to pack data to |
| * @data: data to pack into scatter/gather list |
| * @count: amount of data to pack into the scatter/gather list |
| * |
| * sg_lists have multiple segments of various sizes. This will pack |
| * arbitrary data into an existing scatter gather list, segmenting the |
| * data as necessary within constraints. |
| * |
| */ |
| |
| static int pack_sg_list(struct scatterlist *sg, int start, |
| int limit, char *data, int count) |
| { |
| int s; |
| int index = start; |
| |
| while (count) { |
| s = rest_of_page(data); |
| if (s > count) |
| s = count; |
| BUG_ON(index > limit); |
| /* Make sure we don't terminate early. */ |
| sg_unmark_end(&sg[index]); |
| sg_set_buf(&sg[index++], data, s); |
| count -= s; |
| data += s; |
| } |
| if (index-start) |
| sg_mark_end(&sg[index - 1]); |
| return index-start; |
| } |
| |
| /* We don't currently allow canceling of virtio requests */ |
| static int p9_virtio_cancel(struct p9_client *client, struct p9_req_t *req) |
| { |
| return 1; |
| } |
| |
| /** |
| * pack_sg_list_p - Just like pack_sg_list. Instead of taking a buffer, |
| * this takes a list of pages. |
| * @sg: scatter/gather list to pack into |
| * @start: which segment of the sg_list to start at |
| * @pdata: a list of pages to add into sg. |
| * @nr_pages: number of pages to pack into the scatter/gather list |
| * @data: data to pack into scatter/gather list |
| * @count: amount of data to pack into the scatter/gather list |
| */ |
| static int |
| pack_sg_list_p(struct scatterlist *sg, int start, int limit, |
| struct page **pdata, int nr_pages, char *data, int count) |
| { |
| int i = 0, s; |
| int data_off; |
| int index = start; |
| |
| BUG_ON(nr_pages > (limit - start)); |
| /* |
| * if the first page doesn't start at |
| * page boundary find the offset |
| */ |
| data_off = offset_in_page(data); |
| while (nr_pages) { |
| s = rest_of_page(data); |
| if (s > count) |
| s = count; |
| /* Make sure we don't terminate early. */ |
| sg_unmark_end(&sg[index]); |
| sg_set_page(&sg[index++], pdata[i++], s, data_off); |
| data_off = 0; |
| data += s; |
| count -= s; |
| nr_pages--; |
| } |
| |
| if (index-start) |
| sg_mark_end(&sg[index - 1]); |
| return index - start; |
| } |
| |
| /** |
| * p9_virtio_request - issue a request |
| * @client: client instance issuing the request |
| * @req: request to be issued |
| * |
| */ |
| |
| static int |
| p9_virtio_request(struct p9_client *client, struct p9_req_t *req) |
| { |
| int err; |
| int in, out, out_sgs, in_sgs; |
| unsigned long flags; |
| struct virtio_chan *chan = client->trans; |
| struct scatterlist *sgs[2]; |
| |
| p9_debug(P9_DEBUG_TRANS, "9p debug: virtio request\n"); |
| |
| req->status = REQ_STATUS_SENT; |
| req_retry: |
| spin_lock_irqsave(&chan->lock, flags); |
| |
| out_sgs = in_sgs = 0; |
| /* Handle out VirtIO ring buffers */ |
| out = pack_sg_list(chan->sg, 0, |
| VIRTQUEUE_NUM, req->tc->sdata, req->tc->size); |
| if (out) |
| sgs[out_sgs++] = chan->sg; |
| |
| in = pack_sg_list(chan->sg, out, |
| VIRTQUEUE_NUM, req->rc->sdata, req->rc->capacity); |
| if (in) |
| sgs[out_sgs + in_sgs++] = chan->sg + out; |
| |
| err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc, |
| GFP_ATOMIC); |
| if (err < 0) { |
| if (err == -ENOSPC) { |
| chan->ring_bufs_avail = 0; |
| spin_unlock_irqrestore(&chan->lock, flags); |
| err = wait_event_interruptible(*chan->vc_wq, |
| chan->ring_bufs_avail); |
| if (err == -ERESTARTSYS) |
| return err; |
| |
| p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n"); |
| goto req_retry; |
| } else { |
| spin_unlock_irqrestore(&chan->lock, flags); |
| p9_debug(P9_DEBUG_TRANS, |
| "virtio rpc add_sgs returned failure\n"); |
| return -EIO; |
| } |
| } |
| virtqueue_kick(chan->vq); |
| spin_unlock_irqrestore(&chan->lock, flags); |
| |
| p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n"); |
| return 0; |
| } |
| |
| static int p9_get_mapped_pages(struct virtio_chan *chan, |
| struct page **pages, char *data, |
| int nr_pages, int write, int kern_buf) |
| { |
| int err; |
| if (!kern_buf) { |
| /* |
| * We allow only p9_max_pages pinned. We wait for the |
| * Other zc request to finish here |
| */ |
| if (atomic_read(&vp_pinned) >= chan->p9_max_pages) { |
| err = wait_event_interruptible(vp_wq, |
| (atomic_read(&vp_pinned) < chan->p9_max_pages)); |
| if (err == -ERESTARTSYS) |
| return err; |
| } |
| err = p9_payload_gup(data, &nr_pages, pages, write); |
| if (err < 0) |
| return err; |
| atomic_add(nr_pages, &vp_pinned); |
| } else { |
| /* kernel buffer, no need to pin pages */ |
| int s, index = 0; |
| int count = nr_pages; |
| while (nr_pages) { |
| s = rest_of_page(data); |
| if (is_vmalloc_addr(data)) |
| pages[index++] = vmalloc_to_page(data); |
| else |
| pages[index++] = kmap_to_page(data); |
| data += s; |
| nr_pages--; |
| } |
| nr_pages = count; |
| } |
| return nr_pages; |
| } |
| |
| /** |
| * p9_virtio_zc_request - issue a zero copy request |
| * @client: client instance issuing the request |
| * @req: request to be issued |
| * @uidata: user bffer that should be ued for zero copy read |
| * @uodata: user buffer that shoud be user for zero copy write |
| * @inlen: read buffer size |
| * @olen: write buffer size |
| * @hdrlen: reader header size, This is the size of response protocol data |
| * |
| */ |
| static int |
| p9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req, |
| char *uidata, char *uodata, int inlen, |
| int outlen, int in_hdr_len, int kern_buf) |
| { |
| int in, out, err, out_sgs, in_sgs; |
| unsigned long flags; |
| int in_nr_pages = 0, out_nr_pages = 0; |
| struct page **in_pages = NULL, **out_pages = NULL; |
| struct virtio_chan *chan = client->trans; |
| struct scatterlist *sgs[4]; |
| |
| p9_debug(P9_DEBUG_TRANS, "virtio request\n"); |
| |
| if (uodata) { |
| out_nr_pages = p9_nr_pages(uodata, outlen); |
| out_pages = kmalloc(sizeof(struct page *) * out_nr_pages, |
| GFP_NOFS); |
| if (!out_pages) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| out_nr_pages = p9_get_mapped_pages(chan, out_pages, uodata, |
| out_nr_pages, 0, kern_buf); |
| if (out_nr_pages < 0) { |
| err = out_nr_pages; |
| kfree(out_pages); |
| out_pages = NULL; |
| goto err_out; |
| } |
| } |
| if (uidata) { |
| in_nr_pages = p9_nr_pages(uidata, inlen); |
| in_pages = kmalloc(sizeof(struct page *) * in_nr_pages, |
| GFP_NOFS); |
| if (!in_pages) { |
| err = -ENOMEM; |
| goto err_out; |
| } |
| in_nr_pages = p9_get_mapped_pages(chan, in_pages, uidata, |
| in_nr_pages, 1, kern_buf); |
| if (in_nr_pages < 0) { |
| err = in_nr_pages; |
| kfree(in_pages); |
| in_pages = NULL; |
| goto err_out; |
| } |
| } |
| req->status = REQ_STATUS_SENT; |
| req_retry_pinned: |
| spin_lock_irqsave(&chan->lock, flags); |
| |
| out_sgs = in_sgs = 0; |
| |
| /* out data */ |
| out = pack_sg_list(chan->sg, 0, |
| VIRTQUEUE_NUM, req->tc->sdata, req->tc->size); |
| |
| if (out) |
| sgs[out_sgs++] = chan->sg; |
| |
| if (out_pages) { |
| sgs[out_sgs++] = chan->sg + out; |
| out += pack_sg_list_p(chan->sg, out, VIRTQUEUE_NUM, |
| out_pages, out_nr_pages, uodata, outlen); |
| } |
| |
| /* |
| * Take care of in data |
| * For example TREAD have 11. |
| * 11 is the read/write header = PDU Header(7) + IO Size (4). |
| * Arrange in such a way that server places header in the |
| * alloced memory and payload onto the user buffer. |
| */ |
| in = pack_sg_list(chan->sg, out, |
| VIRTQUEUE_NUM, req->rc->sdata, in_hdr_len); |
| if (in) |
| sgs[out_sgs + in_sgs++] = chan->sg + out; |
| |
| if (in_pages) { |
| sgs[out_sgs + in_sgs++] = chan->sg + out + in; |
| in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM, |
| in_pages, in_nr_pages, uidata, inlen); |
| } |
| |
| BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs)); |
| err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc, |
| GFP_ATOMIC); |
| if (err < 0) { |
| if (err == -ENOSPC) { |
| chan->ring_bufs_avail = 0; |
| spin_unlock_irqrestore(&chan->lock, flags); |
| err = wait_event_interruptible(*chan->vc_wq, |
| chan->ring_bufs_avail); |
| if (err == -ERESTARTSYS) |
| goto err_out; |
| |
| p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n"); |
| goto req_retry_pinned; |
| } else { |
| spin_unlock_irqrestore(&chan->lock, flags); |
| p9_debug(P9_DEBUG_TRANS, |
| "virtio rpc add_sgs returned failure\n"); |
| err = -EIO; |
| goto err_out; |
| } |
| } |
| virtqueue_kick(chan->vq); |
| spin_unlock_irqrestore(&chan->lock, flags); |
| p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n"); |
| err = wait_event_interruptible(*req->wq, |
| req->status >= REQ_STATUS_RCVD); |
| /* |
| * Non kernel buffers are pinned, unpin them |
| */ |
| err_out: |
| if (!kern_buf) { |
| if (in_pages) { |
| p9_release_pages(in_pages, in_nr_pages); |
| atomic_sub(in_nr_pages, &vp_pinned); |
| } |
| if (out_pages) { |
| p9_release_pages(out_pages, out_nr_pages); |
| atomic_sub(out_nr_pages, &vp_pinned); |
| } |
| /* wakeup anybody waiting for slots to pin pages */ |
| wake_up(&vp_wq); |
| } |
| kfree(in_pages); |
| kfree(out_pages); |
| return err; |
| } |
| |
| static ssize_t p9_mount_tag_show(struct device *dev, |
| struct device_attribute *attr, char *buf) |
| { |
| struct virtio_chan *chan; |
| struct virtio_device *vdev; |
| |
| vdev = dev_to_virtio(dev); |
| chan = vdev->priv; |
| |
| return snprintf(buf, chan->tag_len + 1, "%s", chan->tag); |
| } |
| |
| static DEVICE_ATTR(mount_tag, 0444, p9_mount_tag_show, NULL); |
| |
| /** |
| * p9_virtio_probe - probe for existence of 9P virtio channels |
| * @vdev: virtio device to probe |
| * |
| * This probes for existing virtio channels. |
| * |
| */ |
| |
| static int p9_virtio_probe(struct virtio_device *vdev) |
| { |
| __u16 tag_len; |
| char *tag; |
| int err; |
| struct virtio_chan *chan; |
| |
| chan = kmalloc(sizeof(struct virtio_chan), GFP_KERNEL); |
| if (!chan) { |
| pr_err("Failed to allocate virtio 9P channel\n"); |
| err = -ENOMEM; |
| goto fail; |
| } |
| |
| chan->vdev = vdev; |
| |
| /* We expect one virtqueue, for requests. */ |
| chan->vq = virtio_find_single_vq(vdev, req_done, "requests"); |
| if (IS_ERR(chan->vq)) { |
| err = PTR_ERR(chan->vq); |
| goto out_free_vq; |
| } |
| chan->vq->vdev->priv = chan; |
| spin_lock_init(&chan->lock); |
| |
| 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; |
| err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr); |
| if (err) { |
| goto out_free_tag; |
| } |
| chan->vc_wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL); |
| if (!chan->vc_wq) { |
| err = -ENOMEM; |
| goto out_free_tag; |
| } |
| init_waitqueue_head(chan->vc_wq); |
| chan->ring_bufs_avail = 1; |
| /* Ceiling limit to avoid denial of service attacks */ |
| chan->p9_max_pages = nr_free_buffer_pages()/4; |
| |
| mutex_lock(&virtio_9p_lock); |
| list_add_tail(&chan->chan_list, &virtio_chan_list); |
| mutex_unlock(&virtio_9p_lock); |
| |
| /* Let udev rules use the new mount_tag attribute. */ |
| kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE); |
| |
| return 0; |
| |
| out_free_tag: |
| kfree(tag); |
| out_free_vq: |
| vdev->config->del_vqs(vdev); |
| kfree(chan); |
| fail: |
| return err; |
| } |
| |
| |
| /** |
| * p9_virtio_create - allocate a new virtio channel |
| * @client: client instance invoking this transport |
| * @devname: string identifying the channel to connect to (unused) |
| * @args: args passed from sys_mount() for per-transport options (unused) |
| * |
| * This sets up a transport channel for 9p communication. Right now |
| * we only match the first available channel, but eventually we couldlook up |
| * alternate channels by matching devname versus a virtio_config entry. |
| * We use a simple reference count mechanism to ensure that only a single |
| * mount has a channel open at a time. |
| * |
| */ |
| |
| static int |
| p9_virtio_create(struct p9_client *client, const char *devname, char *args) |
| { |
| struct virtio_chan *chan; |
| int ret = -ENOENT; |
| int found = 0; |
| |
| mutex_lock(&virtio_9p_lock); |
| list_for_each_entry(chan, &virtio_chan_list, chan_list) { |
| if (!strncmp(devname, chan->tag, chan->tag_len) && |
| strlen(devname) == chan->tag_len) { |
| if (!chan->inuse) { |
| chan->inuse = true; |
| found = 1; |
| break; |
| } |
| ret = -EBUSY; |
| } |
| } |
| mutex_unlock(&virtio_9p_lock); |
| |
| if (!found) { |
| pr_err("no channels available\n"); |
| return ret; |
| } |
| |
| client->trans = (void *)chan; |
| client->status = Connected; |
| chan->client = client; |
| |
| return 0; |
| } |
| |
| /** |
| * p9_virtio_remove - clean up resources associated with a virtio device |
| * @vdev: virtio device to remove |
| * |
| */ |
| |
| static void p9_virtio_remove(struct virtio_device *vdev) |
| { |
| struct virtio_chan *chan = vdev->priv; |
| |
| if (chan->inuse) |
| p9_virtio_close(chan->client); |
| vdev->config->del_vqs(vdev); |
| |
| mutex_lock(&virtio_9p_lock); |
| list_del(&chan->chan_list); |
| mutex_unlock(&virtio_9p_lock); |
| sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr); |
| kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE); |
| kfree(chan->tag); |
| kfree(chan->vc_wq); |
| kfree(chan); |
| |
| } |
| |
| static struct virtio_device_id id_table[] = { |
| { VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID }, |
| { 0 }, |
| }; |
| |
| static unsigned int features[] = { |
| VIRTIO_9P_MOUNT_TAG, |
| }; |
| |
| /* The standard "struct lguest_driver": */ |
| static struct virtio_driver p9_virtio_drv = { |
| .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 = { |
| .name = "virtio", |
| .create = p9_virtio_create, |
| .close = p9_virtio_close, |
| .request = p9_virtio_request, |
| .zc_request = p9_virtio_zc_request, |
| .cancel = p9_virtio_cancel, |
| /* |
| * We leave one entry for input and one entry for response |
| * headers. We also skip one more entry to accomodate, address |
| * that are not at page boundary, that can result in an extra |
| * page in zero copy. |
| */ |
| .maxsize = PAGE_SIZE * (VIRTQUEUE_NUM - 3), |
| .def = 0, |
| .owner = THIS_MODULE, |
| }; |
| |
| /* The standard init function */ |
| static int __init p9_virtio_init(void) |
| { |
| INIT_LIST_HEAD(&virtio_chan_list); |
| |
| v9fs_register_trans(&p9_virtio_trans); |
| return register_virtio_driver(&p9_virtio_drv); |
| } |
| |
| static void __exit p9_virtio_cleanup(void) |
| { |
| unregister_virtio_driver(&p9_virtio_drv); |
| v9fs_unregister_trans(&p9_virtio_trans); |
| } |
| |
| module_init(p9_virtio_init); |
| module_exit(p9_virtio_cleanup); |
| |
| MODULE_DEVICE_TABLE(virtio, id_table); |
| MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); |
| MODULE_DESCRIPTION("Virtio 9p Transport"); |
| MODULE_LICENSE("GPL"); |