2007-10-23 20:47:31 +02:00
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/*
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* The Guest 9p transport driver
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*
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2008-02-07 02:25:58 +01:00
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* This is a block based transport driver based on the lguest block driver
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* code.
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2007-10-23 20:47:31 +02:00
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*
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*/
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/*
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* Copyright (C) 2007 Eric Van Hensbergen, IBM Corporation
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*
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* Based on virtio console driver
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* Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2
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* as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to:
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* Free Software Foundation
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* 51 Franklin Street, Fifth Floor
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* Boston, MA 02111-1301 USA
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*
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*/
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#include <linux/in.h>
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#include <linux/module.h>
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#include <linux/net.h>
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#include <linux/ipv6.h>
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#include <linux/errno.h>
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#include <linux/kernel.h>
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#include <linux/un.h>
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#include <linux/uaccess.h>
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#include <linux/inet.h>
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#include <linux/idr.h>
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#include <linux/file.h>
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#include <net/9p/9p.h>
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#include <linux/parser.h>
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#include <net/9p/transport.h>
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#include <linux/scatterlist.h>
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#include <linux/virtio.h>
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#include <linux/virtio_9p.h>
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2008-02-07 02:25:58 +01:00
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#define VIRTQUEUE_NUM 128
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2007-10-23 20:47:31 +02:00
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/* a single mutex to manage channel initialization and attachment */
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2008-03-07 18:39:13 +01:00
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static DEFINE_MUTEX(virtio_9p_lock);
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2007-10-23 20:47:31 +02:00
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/* global which tracks highest initialized channel */
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static int chan_index;
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2008-02-07 02:25:58 +01:00
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#define P9_INIT_MAXTAG 16
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2008-03-05 14:08:09 +01:00
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/**
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* enum p9_req_status_t - virtio request status
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* @REQ_STATUS_IDLE: request slot unused
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* @REQ_STATUS_SENT: request sent to server
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* @REQ_STATUS_RCVD: response received from server
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* @REQ_STATUS_FLSH: request has been flushed
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*
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* The @REQ_STATUS_IDLE state is used to mark a request slot as unused
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* but use is actually tracked by the idpool structure which handles tag
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* id allocation.
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*
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*/
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enum p9_req_status_t {
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REQ_STATUS_IDLE,
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REQ_STATUS_SENT,
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REQ_STATUS_RCVD,
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REQ_STATUS_FLSH,
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};
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/**
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* struct p9_req_t - virtio request slots
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* @status: status of this request slot
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* @wq: wait_queue for the client to block on for this request
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*
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* The virtio transport uses an array to track outstanding requests
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* instead of a list. While this may incurr overhead during initial
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* allocation or expansion, it makes request lookup much easier as the
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* tag id is a index into an array. (We use tag+1 so that we can accomodate
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* the -1 tag for the T_VERSION request).
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* This also has the nice effect of only having to allocate wait_queues
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* once, instead of constantly allocating and freeing them. Its possible
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* other resources could benefit from this scheme as well.
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*
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*/
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2008-02-07 02:25:58 +01:00
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struct p9_req_t {
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int status;
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wait_queue_head_t *wq;
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};
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2008-03-05 14:08:09 +01:00
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/**
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* struct virtio_chan - per-instance transport information
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* @initialized: whether the channel is initialized
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* @inuse: whether the channel is in use
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* @lock: protects multiple elements within this structure
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* @vdev: virtio dev associated with this channel
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* @vq: virtio queue associated with this channel
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* @tagpool: accounting for tag ids (and request slots)
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* @reqs: array of request slots
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* @max_tag: current number of request_slots allocated
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* @sg: scatter gather list which is used to pack a request (protected?)
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*
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* We keep all per-channel information in a structure.
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2007-10-23 20:47:31 +02:00
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* This structure is allocated within the devices dev->mem space.
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* A pointer to the structure will get put in the transport private.
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2008-03-05 14:08:09 +01:00
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*
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2007-10-23 20:47:31 +02:00
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*/
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2008-03-05 14:08:09 +01:00
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2007-10-23 20:47:31 +02:00
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static struct virtio_chan {
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2008-03-05 14:08:09 +01:00
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bool initialized;
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bool inuse;
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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spinlock_t lock;
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2007-10-23 20:47:31 +02:00
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struct virtio_device *vdev;
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2008-02-07 02:25:58 +01:00
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struct virtqueue *vq;
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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struct p9_idpool *tagpool;
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struct p9_req_t *reqs;
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int max_tag;
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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/* Scatterlist: can be too big for stack. */
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struct scatterlist sg[VIRTQUEUE_NUM];
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2007-10-23 20:47:31 +02:00
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} channels[MAX_9P_CHAN];
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2008-03-05 14:08:09 +01:00
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/**
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* p9_lookup_tag - Lookup requests by tag
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* @c: virtio channel to lookup tag within
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* @tag: numeric id for transaction
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*
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* this is a simple array lookup, but will grow the
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* request_slots as necessary to accomodate transaction
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* ids which did not previously have a slot.
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*
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* Bugs: there is currently no upper limit on request slots set
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* here, but that should be constrained by the id accounting.
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*/
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2008-02-07 02:25:58 +01:00
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static struct p9_req_t *p9_lookup_tag(struct virtio_chan *c, u16 tag)
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{
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/* This looks up the original request by tag so we know which
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* buffer to read the data into */
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tag++;
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while (tag >= c->max_tag) {
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int old_max = c->max_tag;
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int count;
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if (c->max_tag)
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c->max_tag *= 2;
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else
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c->max_tag = P9_INIT_MAXTAG;
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c->reqs = krealloc(c->reqs, sizeof(struct p9_req_t)*c->max_tag,
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GFP_ATOMIC);
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if (!c->reqs) {
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printk(KERN_ERR "Couldn't grow tag array\n");
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BUG();
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}
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for (count = old_max; count < c->max_tag; count++) {
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c->reqs[count].status = REQ_STATUS_IDLE;
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2008-02-20 01:25:30 +01:00
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c->reqs[count].wq = kmalloc(sizeof(wait_queue_head_t),
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2008-02-07 02:25:58 +01:00
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GFP_ATOMIC);
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if (!c->reqs[count].wq) {
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printk(KERN_ERR "Couldn't grow tag array\n");
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BUG();
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}
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init_waitqueue_head(c->reqs[count].wq);
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}
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}
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return &c->reqs[tag];
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}
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2007-10-23 20:47:31 +02:00
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/* How many bytes left in this page. */
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static unsigned int rest_of_page(void *data)
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{
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return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE);
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}
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2008-03-05 14:08:09 +01:00
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/**
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* p9_virtio_close - reclaim resources of a channel
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* @trans: transport state
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*
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* This reclaims a channel by freeing its resources and
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* reseting its inuse flag.
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*
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*/
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2008-02-07 02:25:58 +01:00
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static void p9_virtio_close(struct p9_trans *trans)
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{
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struct virtio_chan *chan = trans->priv;
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int count;
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2008-05-04 00:29:50 +02:00
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unsigned long flags;
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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spin_lock_irqsave(&chan->lock, flags);
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p9_idpool_destroy(chan->tagpool);
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for (count = 0; count < chan->max_tag; count++)
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kfree(chan->reqs[count].wq);
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kfree(chan->reqs);
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chan->max_tag = 0;
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spin_unlock_irqrestore(&chan->lock, flags);
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2007-10-23 20:47:31 +02:00
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2008-03-07 18:39:13 +01:00
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mutex_lock(&virtio_9p_lock);
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2008-02-07 02:25:58 +01:00
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chan->inuse = false;
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2008-03-07 18:39:13 +01:00
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mutex_unlock(&virtio_9p_lock);
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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kfree(trans);
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2007-10-23 20:47:31 +02:00
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}
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2008-03-05 14:08:09 +01:00
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/**
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* req_done - callback which signals activity from the server
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* @vq: virtio queue activity was received on
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*
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* This notifies us that the server has triggered some activity
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* on the virtio channel - most likely a response to request we
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* sent. Figure out which requests now have responses and wake up
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* those threads.
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*
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* Bugs: could do with some additional sanity checking, but appears to work.
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*
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*/
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2008-02-07 02:25:58 +01:00
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static void req_done(struct virtqueue *vq)
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2007-10-23 20:47:31 +02:00
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{
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2008-02-07 02:25:58 +01:00
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struct virtio_chan *chan = vq->vdev->priv;
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struct p9_fcall *rc;
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unsigned int len;
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unsigned long flags;
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struct p9_req_t *req;
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spin_lock_irqsave(&chan->lock, flags);
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while ((rc = chan->vq->vq_ops->get_buf(chan->vq, &len)) != NULL) {
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req = p9_lookup_tag(chan, rc->tag);
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req->status = REQ_STATUS_RCVD;
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wake_up(req->wq);
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}
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/* In case queue is stopped waiting for more buffers. */
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spin_unlock_irqrestore(&chan->lock, flags);
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}
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2007-10-23 20:47:31 +02:00
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2008-03-05 14:08:09 +01:00
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/**
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* pack_sg_list - pack a scatter gather list from a linear buffer
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* @sg: scatter/gather list to pack into
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* @start: which segment of the sg_list to start at
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* @limit: maximum segment to pack data to
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* @data: data to pack into scatter/gather list
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* @count: amount of data to pack into the scatter/gather list
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*
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* sg_lists have multiple segments of various sizes. This will pack
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* arbitrary data into an existing scatter gather list, segmenting the
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* data as necessary within constraints.
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*
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*/
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2008-02-07 02:25:58 +01:00
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static int
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pack_sg_list(struct scatterlist *sg, int start, int limit, char *data,
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int count)
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{
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int s;
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int index = start;
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while (count) {
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s = rest_of_page(data);
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if (s > count)
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s = count;
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sg_set_buf(&sg[index++], data, s);
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count -= s;
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data += s;
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2008-02-18 03:42:53 +01:00
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BUG_ON(index > limit);
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2008-02-07 02:25:58 +01:00
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}
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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return index-start;
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2007-10-23 20:47:31 +02:00
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}
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2008-03-05 14:08:09 +01:00
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/**
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* p9_virtio_rpc - issue a request and wait for a response
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* @t: transport state
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* @tc: &p9_fcall request to transmit
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* @rc: &p9_fcall to put reponse into
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*
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*/
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2008-02-07 02:25:58 +01:00
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static int
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2008-02-07 02:25:03 +01:00
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p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc)
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2007-10-23 20:47:31 +02:00
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{
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2008-02-07 02:25:58 +01:00
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int in, out;
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int n, err, size;
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struct virtio_chan *chan = t->priv;
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char *rdata;
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struct p9_req_t *req;
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unsigned long flags;
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if (*rc == NULL) {
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2008-02-07 02:25:03 +01:00
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*rc = kmalloc(sizeof(struct p9_fcall) + t->msize, GFP_KERNEL);
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2008-02-07 02:25:58 +01:00
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if (!*rc)
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return -ENOMEM;
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}
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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rdata = (char *)*rc+sizeof(struct p9_fcall);
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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n = P9_NOTAG;
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if (tc->id != P9_TVERSION) {
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n = p9_idpool_get(chan->tagpool);
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if (n < 0)
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return -ENOMEM;
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2007-10-23 20:47:31 +02:00
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}
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2008-02-07 02:25:07 +01:00
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spin_lock_irqsave(&chan->lock, flags);
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2008-02-07 02:25:58 +01:00
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req = p9_lookup_tag(chan, n);
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spin_unlock_irqrestore(&chan->lock, flags);
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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p9_set_tag(tc, n);
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio rpc tag %d\n", n);
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2007-10-23 20:47:31 +02:00
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2008-02-07 02:25:58 +01:00
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out = pack_sg_list(chan->sg, 0, VIRTQUEUE_NUM, tc->sdata, tc->size);
|
2008-02-07 02:25:03 +01:00
|
|
|
in = pack_sg_list(chan->sg, out, VIRTQUEUE_NUM-out, rdata, t->msize);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
req->status = REQ_STATUS_SENT;
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
if (chan->vq->vq_ops->add_buf(chan->vq, chan->sg, out, in, tc)) {
|
|
|
|
P9_DPRINTK(P9_DEBUG_TRANS,
|
|
|
|
"9p debug: virtio rpc add_buf returned failure");
|
|
|
|
return -EIO;
|
|
|
|
}
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
chan->vq->vq_ops->kick(chan->vq);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
wait_event(*req->wq, req->status == REQ_STATUS_RCVD);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
size = le32_to_cpu(*(__le32 *) rdata);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:03 +01:00
|
|
|
err = p9_deserialize_fcall(rdata, size, *rc, t->extended);
|
2008-02-07 02:25:58 +01:00
|
|
|
if (err < 0) {
|
|
|
|
P9_DPRINTK(P9_DEBUG_TRANS,
|
|
|
|
"9p debug: virtio rpc deserialize returned %d\n", err);
|
|
|
|
return err;
|
|
|
|
}
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
#ifdef CONFIG_NET_9P_DEBUG
|
|
|
|
if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) {
|
|
|
|
char buf[150];
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:03 +01:00
|
|
|
p9_printfcall(buf, sizeof(buf), *rc, t->extended);
|
2008-02-07 02:25:58 +01:00
|
|
|
printk(KERN_NOTICE ">>> %p %s\n", t, buf);
|
|
|
|
}
|
|
|
|
#endif
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
if (n != P9_NOTAG && p9_idpool_check(n, chan->tagpool))
|
|
|
|
p9_idpool_put(n, chan->tagpool);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
req->status = REQ_STATUS_IDLE;
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
return 0;
|
2007-10-23 20:47:31 +02:00
|
|
|
}
|
|
|
|
|
2008-03-05 14:08:09 +01:00
|
|
|
/**
|
|
|
|
* p9_virtio_probe - probe for existence of 9P virtio channels
|
|
|
|
* @vdev: virtio device to probe
|
|
|
|
*
|
|
|
|
* This probes for existing virtio channels. At present only
|
|
|
|
* a single channel is in use, so in the future more work may need
|
|
|
|
* to be done here.
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
static int p9_virtio_probe(struct virtio_device *vdev)
|
2007-10-23 20:47:31 +02:00
|
|
|
{
|
|
|
|
int err;
|
|
|
|
struct virtio_chan *chan;
|
|
|
|
int index;
|
|
|
|
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_lock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
index = chan_index++;
|
|
|
|
chan = &channels[index];
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_unlock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
|
|
|
if (chan_index > MAX_9P_CHAN) {
|
|
|
|
printk(KERN_ERR "9p: virtio: Maximum channels exceeded\n");
|
|
|
|
BUG();
|
|
|
|
err = -ENOMEM;
|
|
|
|
goto fail;
|
|
|
|
}
|
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
chan->vdev = vdev;
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
/* We expect one virtqueue, for requests. */
|
|
|
|
chan->vq = vdev->config->find_vq(vdev, 0, req_done);
|
|
|
|
if (IS_ERR(chan->vq)) {
|
|
|
|
err = PTR_ERR(chan->vq);
|
|
|
|
goto out_free_vq;
|
2007-10-23 20:47:31 +02:00
|
|
|
}
|
2008-02-07 02:25:58 +01:00
|
|
|
chan->vq->vdev->priv = chan;
|
|
|
|
spin_lock_init(&chan->lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
sg_init_table(chan->sg, VIRTQUEUE_NUM);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
|
|
|
chan->inuse = false;
|
|
|
|
chan->initialized = true;
|
|
|
|
return 0;
|
|
|
|
|
2008-02-07 02:25:58 +01:00
|
|
|
out_free_vq:
|
|
|
|
vdev->config->del_vq(chan->vq);
|
2007-10-23 20:47:31 +02:00
|
|
|
fail:
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_lock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
chan_index--;
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_unlock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
2008-03-05 14:08:09 +01:00
|
|
|
|
|
|
|
/**
|
|
|
|
* p9_virtio_create - allocate a new virtio channel
|
|
|
|
* @devname: string identifying the channel to connect to (unused)
|
|
|
|
* @args: args passed from sys_mount() for per-transport options (unused)
|
|
|
|
* @msize: requested maximum packet size
|
|
|
|
* @extended: 9p2000.u enabled flag
|
|
|
|
*
|
|
|
|
* This sets up a transport channel for 9p communication. Right now
|
2007-10-23 20:47:31 +02:00
|
|
|
* 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
|
2008-03-05 14:08:09 +01:00
|
|
|
* mount has a channel open at a time.
|
|
|
|
*
|
|
|
|
* Bugs: doesn't allow identification of a specific channel
|
|
|
|
* to allocate, channels are allocated sequentially. This was
|
|
|
|
* a pragmatic decision to get things rolling, but ideally some
|
|
|
|
* way of identifying the channel to attach to would be nice
|
|
|
|
* if we are going to support multiple channels.
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
2008-02-07 02:25:03 +01:00
|
|
|
static struct p9_trans *
|
|
|
|
p9_virtio_create(const char *devname, char *args, int msize,
|
|
|
|
unsigned char extended)
|
2007-10-23 20:47:31 +02:00
|
|
|
{
|
|
|
|
struct p9_trans *trans;
|
|
|
|
struct virtio_chan *chan = channels;
|
2008-02-07 02:25:58 +01:00
|
|
|
int index = 0;
|
2007-10-23 20:47:31 +02:00
|
|
|
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_lock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
while (index < MAX_9P_CHAN) {
|
|
|
|
if (chan->initialized && !chan->inuse) {
|
|
|
|
chan->inuse = true;
|
|
|
|
break;
|
|
|
|
} else {
|
|
|
|
index++;
|
|
|
|
chan = &channels[index];
|
|
|
|
}
|
|
|
|
}
|
2008-03-07 18:39:13 +01:00
|
|
|
mutex_unlock(&virtio_9p_lock);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
|
|
|
if (index >= MAX_9P_CHAN) {
|
2008-02-07 02:25:58 +01:00
|
|
|
printk(KERN_ERR "9p: no channels available\n");
|
|
|
|
return ERR_PTR(-ENODEV);
|
|
|
|
}
|
|
|
|
|
|
|
|
chan->tagpool = p9_idpool_create();
|
|
|
|
if (IS_ERR(chan->tagpool)) {
|
|
|
|
printk(KERN_ERR "9p: couldn't allocate tagpool\n");
|
|
|
|
return ERR_PTR(-ENOMEM);
|
2007-10-23 20:47:31 +02:00
|
|
|
}
|
2008-02-07 02:25:58 +01:00
|
|
|
p9_idpool_get(chan->tagpool); /* reserve tag 0 */
|
|
|
|
chan->max_tag = 0;
|
|
|
|
chan->reqs = NULL;
|
2007-10-23 20:47:31 +02:00
|
|
|
|
|
|
|
trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL);
|
|
|
|
if (!trans) {
|
|
|
|
printk(KERN_ERR "9p: couldn't allocate transport\n");
|
|
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
}
|
2008-02-07 02:25:03 +01:00
|
|
|
trans->extended = extended;
|
|
|
|
trans->msize = msize;
|
2007-10-23 20:47:31 +02:00
|
|
|
trans->close = p9_virtio_close;
|
2008-02-07 02:25:58 +01:00
|
|
|
trans->rpc = p9_virtio_rpc;
|
2007-10-23 20:47:31 +02:00
|
|
|
trans->priv = chan;
|
|
|
|
|
|
|
|
return trans;
|
|
|
|
}
|
|
|
|
|
2008-03-05 14:08:09 +01:00
|
|
|
/**
|
|
|
|
* p9_virtio_remove - clean up resources associated with a virtio device
|
|
|
|
* @vdev: virtio device to remove
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
|
2008-02-07 02:25:04 +01:00
|
|
|
static void p9_virtio_remove(struct virtio_device *vdev)
|
|
|
|
{
|
|
|
|
struct virtio_chan *chan = vdev->priv;
|
|
|
|
|
|
|
|
BUG_ON(chan->inuse);
|
|
|
|
|
|
|
|
if (chan->initialized) {
|
|
|
|
vdev->config->del_vq(chan->vq);
|
|
|
|
chan->initialized = false;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2007-10-23 20:47:31 +02:00
|
|
|
#define VIRTIO_ID_9P 9
|
|
|
|
|
|
|
|
static struct virtio_device_id id_table[] = {
|
|
|
|
{ VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID },
|
|
|
|
{ 0 },
|
|
|
|
};
|
|
|
|
|
|
|
|
/* 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,
|
2008-02-07 02:25:04 +01:00
|
|
|
.remove = p9_virtio_remove,
|
2007-10-23 20:47:31 +02:00
|
|
|
};
|
|
|
|
|
|
|
|
static struct p9_trans_module p9_virtio_trans = {
|
|
|
|
.name = "virtio",
|
|
|
|
.create = p9_virtio_create,
|
2008-02-07 02:25:58 +01:00
|
|
|
.maxsize = PAGE_SIZE*16,
|
2007-10-23 20:47:31 +02:00
|
|
|
.def = 0,
|
2008-09-24 23:22:23 +02:00
|
|
|
.owner = THIS_MODULE,
|
2007-10-23 20:47:31 +02:00
|
|
|
};
|
|
|
|
|
|
|
|
/* The standard init function */
|
|
|
|
static int __init p9_virtio_init(void)
|
|
|
|
{
|
|
|
|
int count;
|
|
|
|
|
|
|
|
for (count = 0; count < MAX_9P_CHAN; count++)
|
|
|
|
channels[count].initialized = false;
|
|
|
|
|
|
|
|
v9fs_register_trans(&p9_virtio_trans);
|
|
|
|
return register_virtio_driver(&p9_virtio_drv);
|
|
|
|
}
|
|
|
|
|
2008-02-07 02:25:04 +01:00
|
|
|
static void __exit p9_virtio_cleanup(void)
|
|
|
|
{
|
|
|
|
unregister_virtio_driver(&p9_virtio_drv);
|
2008-09-24 23:22:23 +02:00
|
|
|
v9fs_unregister_trans(&p9_virtio_trans);
|
2008-02-07 02:25:04 +01:00
|
|
|
}
|
|
|
|
|
2007-10-23 20:47:31 +02:00
|
|
|
module_init(p9_virtio_init);
|
2008-02-07 02:25:04 +01:00
|
|
|
module_exit(p9_virtio_cleanup);
|
2007-10-23 20:47:31 +02:00
|
|
|
|
|
|
|
MODULE_DEVICE_TABLE(virtio, id_table);
|
|
|
|
MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>");
|
|
|
|
MODULE_DESCRIPTION("Virtio 9p Transport");
|
|
|
|
MODULE_LICENSE("GPL");
|