1b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen/* 2fea511a644fb0fb938309c6ab286725ac31b87e2Eric Van Hensbergen * The Virtio 9p transport driver 3b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 4e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen * This is a block based transport driver based on the lguest block driver 5e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen * code. 6b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 7fea511a644fb0fb938309c6ab286725ac31b87e2Eric Van Hensbergen * Copyright (C) 2007, 2008 Eric Van Hensbergen, IBM Corporation 8b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 9b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * Based on virtio console driver 10b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation 11b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 12b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * This program is free software; you can redistribute it and/or modify 13b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * it under the terms of the GNU General Public License version 2 14b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * as published by the Free Software Foundation. 15b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 16b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * This program is distributed in the hope that it will be useful, 17b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * but WITHOUT ANY WARRANTY; without even the implied warranty of 18b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 19b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * GNU General Public License for more details. 20b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 21b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * You should have received a copy of the GNU General Public License 22b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * along with this program; if not, write to: 23b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * Free Software Foundation 24b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 51 Franklin Street, Fifth Floor 25b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * Boston, MA 02111-1301 USA 26b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * 27b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen */ 28b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 295d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 305d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches 31b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/in.h> 32b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/module.h> 33b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/net.h> 34b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/ipv6.h> 35b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/errno.h> 36b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/kernel.h> 37b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/un.h> 38b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/uaccess.h> 39b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/inet.h> 40b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/idr.h> 41b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/file.h> 42b9cdc88df8e63e81c723b82c286fc97f5d0dc325Will Deacon#include <linux/highmem.h> 435a0e3ad6af8660be21ca98a971cd00f331318c05Tejun Heo#include <linux/slab.h> 44b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <net/9p/9p.h> 45b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/parser.h> 468b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen#include <net/9p/client.h> 47b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <net/9p/transport.h> 48b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/scatterlist.h> 4968da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV)#include <linux/swap.h> 50b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/virtio.h> 51b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen#include <linux/virtio_9p.h> 524038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV)#include "trans_common.h" 53b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 54e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen#define VIRTQUEUE_NUM 128 55e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen 56b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen/* a single mutex to manage channel initialization and attachment */ 57c1549497e903a1ffa1c5808337a987180e480e7aJosef 'Jeff' Sipekstatic DEFINE_MUTEX(virtio_9p_lock); 5868da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV)static DECLARE_WAIT_QUEUE_HEAD(vp_wq); 5968da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV)static atomic_t vp_pinned = ATOMIC_INIT(0); 60b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 61ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 62ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * struct virtio_chan - per-instance transport information 63ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @initialized: whether the channel is initialized 64ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @inuse: whether the channel is in use 65ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @lock: protects multiple elements within this structure 660e15597ebfe00e28857185f46aba00f400480ffeAbhishek Kulkarni * @client: client instance 67ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @vdev: virtio dev associated with this channel 68ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @vq: virtio queue associated with this channel 69ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @sg: scatter gather list which is used to pack a request (protected?) 70ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 71ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * We keep all per-channel information in a structure. 72b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * This structure is allocated within the devices dev->mem space. 73b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * A pointer to the structure will get put in the transport private. 74ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 75b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen */ 76ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 7737c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.Vstruct virtio_chan { 78ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen bool inuse; 79b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 80e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen spinlock_t lock; 81e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen 82fea511a644fb0fb938309c6ab286725ac31b87e2Eric Van Hensbergen struct p9_client *client; 83b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen struct virtio_device *vdev; 84e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen struct virtqueue *vq; 8552f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) int ring_bufs_avail; 8652f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) wait_queue_head_t *vc_wq; 8768da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) /* This is global limit. Since we don't have a global structure, 8868da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) * will be placing it in each channel. 8968da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) */ 907293bfba03e8283e29558c20aee279642f619c43Zhang Yanfei unsigned long p9_max_pages; 91e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen /* Scatterlist: can be too big for stack. */ 92e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen struct scatterlist sg[VIRTQUEUE_NUM]; 9337c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V 9497ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V int tag_len; 9597ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V /* 9697ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V * tag name to identify a mount Non-null terminated 9797ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V */ 9897ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V char *tag; 9997ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V 10037c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V struct list_head chan_list; 10137c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V}; 10237c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V 10337c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.Vstatic struct list_head virtio_chan_list; 104b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 105b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen/* How many bytes left in this page. */ 106b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenstatic unsigned int rest_of_page(void *data) 107b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 108b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE); 109b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 110b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 111ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 112ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * p9_virtio_close - reclaim resources of a channel 1130e15597ebfe00e28857185f46aba00f400480ffeAbhishek Kulkarni * @client: client instance 114ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 115ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * This reclaims a channel by freeing its resources and 116ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * reseting its inuse flag. 117ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 118ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 119ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 1208b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergenstatic void p9_virtio_close(struct p9_client *client) 121e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen{ 1228b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen struct virtio_chan *chan = client->trans; 123b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 124c1549497e903a1ffa1c5808337a987180e480e7aJosef 'Jeff' Sipek mutex_lock(&virtio_9p_lock); 125fb786100f7c75e154e63d0f5a2982e6d46dfb602Aneesh Kumar K.V if (chan) 126fb786100f7c75e154e63d0f5a2982e6d46dfb602Aneesh Kumar K.V chan->inuse = false; 127c1549497e903a1ffa1c5808337a987180e480e7aJosef 'Jeff' Sipek mutex_unlock(&virtio_9p_lock); 128b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 129b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 130ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 131ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * req_done - callback which signals activity from the server 132ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @vq: virtio queue activity was received on 133ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 134ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * This notifies us that the server has triggered some activity 135ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * on the virtio channel - most likely a response to request we 136ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * sent. Figure out which requests now have responses and wake up 137ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * those threads. 138ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 139ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * Bugs: could do with some additional sanity checking, but appears to work. 140ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 141ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 142ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 143e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergenstatic void req_done(struct virtqueue *vq) 144b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 145e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen struct virtio_chan *chan = vq->vdev->priv; 146e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen struct p9_fcall *rc; 147e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen unsigned int len; 148e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen struct p9_req_t *req; 149419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) unsigned long flags; 150e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen 1515d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, ": request done\n"); 15291b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen 153a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) while (1) { 154419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) spin_lock_irqsave(&chan->lock, flags); 155419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) rc = virtqueue_get_buf(chan->vq, &len); 156a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) if (rc == NULL) { 15752f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) spin_unlock_irqrestore(&chan->lock, flags); 158a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) break; 159a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) } 160a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) chan->ring_bufs_avail = 1; 161a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) spin_unlock_irqrestore(&chan->lock, flags); 162a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) /* Wakeup if anyone waiting for VirtIO ring space. */ 163a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) wake_up(chan->vc_wq); 1645d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, ": rc %p\n", rc); 1655d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, ": lookup tag %d\n", rc->tag); 166a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) req = p9_tag_lookup(chan->client, rc->tag); 1672b6e72ed747f68a038df616efd86744b3644d694Dominique Martinet p9_client_cb(chan->client, req, REQ_STATUS_RCVD); 168a01a984035ea799b14aa5e874dcaeb122f09c4b4Venkateswararao Jujjuri (JV) } 169e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen} 170b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 171ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 172ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * pack_sg_list - pack a scatter gather list from a linear buffer 173ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @sg: scatter/gather list to pack into 174ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @start: which segment of the sg_list to start at 175ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @limit: maximum segment to pack data to 176ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @data: data to pack into scatter/gather list 177ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @count: amount of data to pack into the scatter/gather list 178ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 179ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * sg_lists have multiple segments of various sizes. This will pack 180ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * arbitrary data into an existing scatter gather list, segmenting the 181ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * data as necessary within constraints. 182ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 183ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 184ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 185abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vstatic int pack_sg_list(struct scatterlist *sg, int start, 186abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int limit, char *data, int count) 187e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen{ 188e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen int s; 189e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen int index = start; 190e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen 191e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen while (count) { 192e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen s = rest_of_page(data); 193e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen if (s > count) 194e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen s = count; 1955fcb08befaf57faa1b00e514915c1660252b8c26Sasha Levin BUG_ON(index > limit); 1960b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell /* Make sure we don't terminate early. */ 1970b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sg_unmark_end(&sg[index]); 198e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen sg_set_buf(&sg[index++], data, s); 199e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen count -= s; 200e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen data += s; 201e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen } 2020b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (index-start) 2030b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sg_mark_end(&sg[index - 1]); 204e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen return index-start; 205b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 206b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 20791b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen/* We don't currently allow canceling of virtio requests */ 20891b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergenstatic int p9_virtio_cancel(struct p9_client *client, struct p9_req_t *req) 20991b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen{ 21091b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen return 1; 21191b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen} 21291b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen 213ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 2144038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) * pack_sg_list_p - Just like pack_sg_list. Instead of taking a buffer, 2154038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) * this takes a list of pages. 2164038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) * @sg: scatter/gather list to pack into 2174038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) * @start: which segment of the sg_list to start at 2182c53040f018b6c36a46eec75b9b937aaa5f78e6dBen Hutchings * @pdata: a list of pages to add into sg. 219abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @nr_pages: number of pages to pack into the scatter/gather list 220abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @data: data to pack into scatter/gather list 2214038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) * @count: amount of data to pack into the scatter/gather list 2224038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) */ 2234038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV)static int 224abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vpack_sg_list_p(struct scatterlist *sg, int start, int limit, 225abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V struct page **pdata, int nr_pages, char *data, int count) 2264038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV){ 227abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int i = 0, s; 228abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int data_off; 2294038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) int index = start; 2304038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 231abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V BUG_ON(nr_pages > (limit - start)); 232abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* 233abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * if the first page doesn't start at 234abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * page boundary find the offset 235abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V */ 236abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V data_off = offset_in_page(data); 237abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V while (nr_pages) { 238abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V s = rest_of_page(data); 239abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (s > count) 240abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V s = count; 2410b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell /* Make sure we don't terminate early. */ 2420b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sg_unmark_end(&sg[index]); 243abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V sg_set_page(&sg[index++], pdata[i++], s, data_off); 244abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V data_off = 0; 245abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V data += s; 2464038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) count -= s; 247abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V nr_pages--; 2484038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 2490b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 2500b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (index-start) 2510b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sg_mark_end(&sg[index - 1]); 252abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return index - start; 2534038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV)} 2544038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 2554038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV)/** 25691b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen * p9_virtio_request - issue a request 2570e15597ebfe00e28857185f46aba00f400480ffeAbhishek Kulkarni * @client: client instance issuing the request 2580e15597ebfe00e28857185f46aba00f400480ffeAbhishek Kulkarni * @req: request to be issued 259ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 260ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 261ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 262e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergenstatic int 26391b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergenp9_virtio_request(struct p9_client *client, struct p9_req_t *req) 264b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 265abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int err; 2660b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell int in, out, out_sgs, in_sgs; 267419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) unsigned long flags; 268abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V struct virtio_chan *chan = client->trans; 2690b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell struct scatterlist *sgs[2]; 270b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 2715d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "9p debug: virtio request\n"); 272b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 273419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) req->status = REQ_STATUS_SENT; 274abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vreq_retry: 275abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V spin_lock_irqsave(&chan->lock, flags); 276abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V 2770b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell out_sgs = in_sgs = 0; 278abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* Handle out VirtIO ring buffers */ 279abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out = pack_sg_list(chan->sg, 0, 280abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V VIRTQUEUE_NUM, req->tc->sdata, req->tc->size); 2810b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (out) 2820b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs++] = chan->sg; 283419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) 284abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in = pack_sg_list(chan->sg, out, 285abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V VIRTQUEUE_NUM, req->rc->sdata, req->rc->capacity); 2860b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (in) 2870b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs + in_sgs++] = chan->sg + out; 2884038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 2890b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc, 290f96fde41f7f9af6cf20f6a1919f5d9670f84d574Rusty Russell GFP_ATOMIC); 291abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (err < 0) { 292abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (err == -ENOSPC) { 293abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V chan->ring_bufs_avail = 0; 294abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V spin_unlock_irqrestore(&chan->lock, flags); 295abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = wait_event_interruptible(*chan->vc_wq, 296abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V chan->ring_bufs_avail); 29768da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) if (err == -ERESTARTSYS) 29868da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) return err; 29968da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) 3005d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n"); 301abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto req_retry; 3024038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } else { 303abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V spin_unlock_irqrestore(&chan->lock, flags); 3045d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, 3050b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell "virtio rpc add_sgs returned failure\n"); 306abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return -EIO; 3074038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 308abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 309abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V virtqueue_kick(chan->vq); 310abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V spin_unlock_irqrestore(&chan->lock, flags); 3114038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 3125d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n"); 313abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return 0; 314abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V} 315abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V 316abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vstatic int p9_get_mapped_pages(struct virtio_chan *chan, 317abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V struct page **pages, char *data, 318abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int nr_pages, int write, int kern_buf) 319abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V{ 320abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int err; 321abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (!kern_buf) { 322abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* 323abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * We allow only p9_max_pages pinned. We wait for the 324abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * Other zc request to finish here 325abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V */ 326abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (atomic_read(&vp_pinned) >= chan->p9_max_pages) { 327abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = wait_event_interruptible(vp_wq, 328abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V (atomic_read(&vp_pinned) < chan->p9_max_pages)); 329abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (err == -ERESTARTSYS) 330abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return err; 331abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 332abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = p9_payload_gup(data, &nr_pages, pages, write); 333abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (err < 0) 3344038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) return err; 335abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V atomic_add(nr_pages, &vp_pinned); 336abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } else { 337abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* kernel buffer, no need to pin pages */ 338abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int s, index = 0; 339abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int count = nr_pages; 340abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V while (nr_pages) { 341abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V s = rest_of_page(data); 342b6f52ae2f0d32387bde2b89883e3b64d88b9bfe8Richard Yao if (is_vmalloc_addr(data)) 343b6f52ae2f0d32387bde2b89883e3b64d88b9bfe8Richard Yao pages[index++] = vmalloc_to_page(data); 344b6f52ae2f0d32387bde2b89883e3b64d88b9bfe8Richard Yao else 345b6f52ae2f0d32387bde2b89883e3b64d88b9bfe8Richard Yao pages[index++] = kmap_to_page(data); 346abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V data += s; 347abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V nr_pages--; 3484038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 349abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V nr_pages = count; 3504038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 351abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return nr_pages; 352abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V} 3534038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 354abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V/** 355abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * p9_virtio_zc_request - issue a zero copy request 356abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @client: client instance issuing the request 357abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @req: request to be issued 358abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @uidata: user bffer that should be ued for zero copy read 359abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @uodata: user buffer that shoud be user for zero copy write 360abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @inlen: read buffer size 361abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @olen: write buffer size 362abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * @hdrlen: reader header size, This is the size of response protocol data 363abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * 364abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V */ 365abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vstatic int 366abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vp9_virtio_zc_request(struct p9_client *client, struct p9_req_t *req, 367abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V char *uidata, char *uodata, int inlen, 368abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int outlen, int in_hdr_len, int kern_buf) 369abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V{ 3700b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell int in, out, err, out_sgs, in_sgs; 371abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V unsigned long flags; 372abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V int in_nr_pages = 0, out_nr_pages = 0; 373abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V struct page **in_pages = NULL, **out_pages = NULL; 374abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V struct virtio_chan *chan = client->trans; 3750b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell struct scatterlist *sgs[4]; 3764038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) 3775d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "virtio request\n"); 378abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V 379abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (uodata) { 380abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_nr_pages = p9_nr_pages(uodata, outlen); 381abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_pages = kmalloc(sizeof(struct page *) * out_nr_pages, 382abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V GFP_NOFS); 383abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (!out_pages) { 384abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = -ENOMEM; 385abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 386abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 387abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_nr_pages = p9_get_mapped_pages(chan, out_pages, uodata, 388abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_nr_pages, 0, kern_buf); 389abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (out_nr_pages < 0) { 390abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = out_nr_pages; 391abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V kfree(out_pages); 392abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_pages = NULL; 393abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 3944038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 3954038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 396abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (uidata) { 397abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_nr_pages = p9_nr_pages(uidata, inlen); 398abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_pages = kmalloc(sizeof(struct page *) * in_nr_pages, 399abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V GFP_NOFS); 400abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (!in_pages) { 401abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = -ENOMEM; 402abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 403abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 404abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_nr_pages = p9_get_mapped_pages(chan, in_pages, uidata, 405abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_nr_pages, 1, kern_buf); 406abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (in_nr_pages < 0) { 407abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = in_nr_pages; 408abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V kfree(in_pages); 409abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_pages = NULL; 410abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 4114038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 4124038866dab4e461e0ef144458bad9d70ce0c98c1Venkateswararao Jujjuri (JV) } 413abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V req->status = REQ_STATUS_SENT; 414abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Vreq_retry_pinned: 415abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V spin_lock_irqsave(&chan->lock, flags); 4160b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 4170b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell out_sgs = in_sgs = 0; 4180b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 419abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* out data */ 420abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out = pack_sg_list(chan->sg, 0, 421abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V VIRTQUEUE_NUM, req->tc->sdata, req->tc->size); 422abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V 4230b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (out) 4240b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs++] = chan->sg; 4250b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 4260b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (out_pages) { 4270b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs++] = chan->sg + out; 428abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out += pack_sg_list_p(chan->sg, out, VIRTQUEUE_NUM, 429abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V out_pages, out_nr_pages, uodata, outlen); 4300b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell } 4310b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 432abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* 433abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * Take care of in data 434abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * For example TREAD have 11. 435abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * 11 is the read/write header = PDU Header(7) + IO Size (4). 436abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * Arrange in such a way that server places header in the 437abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * alloced memory and payload onto the user buffer. 438abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V */ 439abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in = pack_sg_list(chan->sg, out, 440abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V VIRTQUEUE_NUM, req->rc->sdata, in_hdr_len); 4410b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (in) 4420b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs + in_sgs++] = chan->sg + out; 4430b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell 4440b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell if (in_pages) { 4450b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell sgs[out_sgs + in_sgs++] = chan->sg + out + in; 446abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in += pack_sg_list_p(chan->sg, out + in, VIRTQUEUE_NUM, 447abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V in_pages, in_nr_pages, uidata, inlen); 4480b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell } 449b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 4500b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell BUG_ON(out_sgs + in_sgs > ARRAY_SIZE(sgs)); 4510b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell err = virtqueue_add_sgs(chan->vq, sgs, out_sgs, in_sgs, req->tc, 452f96fde41f7f9af6cf20f6a1919f5d9670f84d574Rusty Russell GFP_ATOMIC); 453419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) if (err < 0) { 45452f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) if (err == -ENOSPC) { 45552f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) chan->ring_bufs_avail = 0; 45652f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) spin_unlock_irqrestore(&chan->lock, flags); 45752f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) err = wait_event_interruptible(*chan->vc_wq, 458abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V chan->ring_bufs_avail); 45952f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) if (err == -ERESTARTSYS) 460abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 46152f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) 4625d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "Retry virtio request\n"); 463316ad5501c2098cb2a2a25ed77a0421f1671411cVenkateswararao Jujjuri (JV) goto req_retry_pinned; 46452f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) } else { 46552f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) spin_unlock_irqrestore(&chan->lock, flags); 4665d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, 4670b36f1adcb5adace6d45ca4d9a0f00860e60d012Rusty Russell "virtio rpc add_sgs returned failure\n"); 468abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = -EIO; 469abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V goto err_out; 47052f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) } 471e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen } 472dc3f5e68f846eec38fb31d78f0b6e83633ad375eMichael S. Tsirkin virtqueue_kick(chan->vq); 473419b39561e698d73a42f8010655d22e0134486daVenkateswararao Jujjuri (JV) spin_unlock_irqrestore(&chan->lock, flags); 4745d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches p9_debug(P9_DEBUG_TRANS, "virtio request kicked\n"); 475abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V err = wait_event_interruptible(*req->wq, 476abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V req->status >= REQ_STATUS_RCVD); 477abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* 478abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V * Non kernel buffers are pinned, unpin them 479abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V */ 480abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.Verr_out: 481abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (!kern_buf) { 482abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (in_pages) { 483abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V p9_release_pages(in_pages, in_nr_pages); 484abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V atomic_sub(in_nr_pages, &vp_pinned); 485abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 486abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V if (out_pages) { 487abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V p9_release_pages(out_pages, out_nr_pages); 488abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V atomic_sub(out_nr_pages, &vp_pinned); 489abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 490abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V /* wakeup anybody waiting for slots to pin pages */ 491abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V wake_up(&vp_wq); 492abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V } 493abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V kfree(in_pages); 494abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V kfree(out_pages); 495abfa034e4b8ed0046fa589769e9840af645bc4baAneesh Kumar K.V return err; 496b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 497b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 49886c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.Vstatic ssize_t p9_mount_tag_show(struct device *dev, 49986c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V struct device_attribute *attr, char *buf) 50086c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V{ 50186c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V struct virtio_chan *chan; 50286c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V struct virtio_device *vdev; 50386c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V 50486c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V vdev = dev_to_virtio(dev); 50586c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V chan = vdev->priv; 50686c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V 50786c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V return snprintf(buf, chan->tag_len + 1, "%s", chan->tag); 50886c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V} 50986c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V 51086c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.Vstatic DEVICE_ATTR(mount_tag, 0444, p9_mount_tag_show, NULL); 51186c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V 512ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 513ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * p9_virtio_probe - probe for existence of 9P virtio channels 514ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @vdev: virtio device to probe 515ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 51637c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V * This probes for existing virtio channels. 517ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 518ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 519ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 520e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergenstatic int p9_virtio_probe(struct virtio_device *vdev) 521b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 52297ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V __u16 tag_len; 52397ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V char *tag; 524b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen int err; 525b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen struct virtio_chan *chan; 526b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 52737c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V chan = kmalloc(sizeof(struct virtio_chan), GFP_KERNEL); 52837c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V if (!chan) { 5295d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches pr_err("Failed to allocate virtio 9P channel\n"); 530b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen err = -ENOMEM; 531b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen goto fail; 532b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen } 533b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 534e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen chan->vdev = vdev; 535b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 536e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen /* We expect one virtqueue, for requests. */ 537d2a7ddda9ffb1c8961abff6714b0f1eb925c120fMichael S. Tsirkin chan->vq = virtio_find_single_vq(vdev, req_done, "requests"); 538e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen if (IS_ERR(chan->vq)) { 539e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen err = PTR_ERR(chan->vq); 540e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen goto out_free_vq; 541b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen } 542e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen chan->vq->vdev->priv = chan; 543e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen spin_lock_init(&chan->lock); 544b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 545e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen sg_init_table(chan->sg, VIRTQUEUE_NUM); 546b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 547b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen chan->inuse = false; 54897ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V if (virtio_has_feature(vdev, VIRTIO_9P_MOUNT_TAG)) { 549855e0c5288177bcb193f6f6316952d2490478e1cRusty Russell virtio_cread(vdev, struct virtio_9p_config, tag_len, &tag_len); 55097ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V } else { 55197ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V err = -EINVAL; 55297ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V goto out_free_vq; 55397ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V } 55497ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V tag = kmalloc(tag_len, GFP_KERNEL); 55597ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V if (!tag) { 55697ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V err = -ENOMEM; 55797ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V goto out_free_vq; 55897ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V } 559855e0c5288177bcb193f6f6316952d2490478e1cRusty Russell 560855e0c5288177bcb193f6f6316952d2490478e1cRusty Russell virtio_cread_bytes(vdev, offsetof(struct virtio_9p_config, tag), 561855e0c5288177bcb193f6f6316952d2490478e1cRusty Russell tag, tag_len); 56297ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V chan->tag = tag; 56397ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V chan->tag_len = tag_len; 56486c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V err = sysfs_create_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr); 56586c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V if (err) { 56652f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) goto out_free_tag; 56786c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V } 56852f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) chan->vc_wq = kmalloc(sizeof(wait_queue_head_t), GFP_KERNEL); 56952f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) if (!chan->vc_wq) { 57052f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) err = -ENOMEM; 57152f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) goto out_free_tag; 57252f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) } 57352f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) init_waitqueue_head(chan->vc_wq); 57452f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) chan->ring_bufs_avail = 1; 57568da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) /* Ceiling limit to avoid denial of service attacks */ 57668da9ba4eeadae86ad42e52b80822fbd56971267Venkateswararao Jujjuri (JV) chan->p9_max_pages = nr_free_buffer_pages()/4; 57752f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) 57864b4cc3911fe8284dfb3cfdb8065c100b818bab8Michael S. Tsirkin virtio_device_ready(vdev); 57964b4cc3911fe8284dfb3cfdb8065c100b818bab8Michael S. Tsirkin 58037c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V mutex_lock(&virtio_9p_lock); 58137c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V list_add_tail(&chan->chan_list, &virtio_chan_list); 58237c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V mutex_unlock(&virtio_9p_lock); 583e0d6cb9cd3a3ac8a3b8e5b22b83c4f8619786f22Michael Marineau 584e0d6cb9cd3a3ac8a3b8e5b22b83c4f8619786f22Michael Marineau /* Let udev rules use the new mount_tag attribute. */ 585e0d6cb9cd3a3ac8a3b8e5b22b83c4f8619786f22Michael Marineau kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE); 586e0d6cb9cd3a3ac8a3b8e5b22b83c4f8619786f22Michael Marineau 587b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen return 0; 588b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 58952f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV)out_free_tag: 59052f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) kfree(tag); 591e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergenout_free_vq: 592d2a7ddda9ffb1c8961abff6714b0f1eb925c120fMichael S. Tsirkin vdev->config->del_vqs(vdev); 59337c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V kfree(chan); 594b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenfail: 595b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen return err; 596b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 597b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 598ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 599ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 600ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * p9_virtio_create - allocate a new virtio channel 6018b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen * @client: client instance invoking this transport 602ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @devname: string identifying the channel to connect to (unused) 603ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @args: args passed from sys_mount() for per-transport options (unused) 604ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 605ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * This sets up a transport channel for 9p communication. Right now 606b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * we only match the first available channel, but eventually we couldlook up 607b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * alternate channels by matching devname versus a virtio_config entry. 608b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen * We use a simple reference count mechanism to ensure that only a single 609ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * mount has a channel open at a time. 610ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 611ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 612ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 6138b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergenstatic int 6148b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergenp9_virtio_create(struct p9_client *client, const char *devname, char *args) 615b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 61637c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V struct virtio_chan *chan; 617c1a7c2262035e83a8f70ebe1328b3451702cf51bAneesh Kumar K.V int ret = -ENOENT; 61837c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V int found = 0; 619b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 620c1549497e903a1ffa1c5808337a987180e480e7aJosef 'Jeff' Sipek mutex_lock(&virtio_9p_lock); 62137c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V list_for_each_entry(chan, &virtio_chan_list, chan_list) { 6220b20406cda621c2495d10baab1e87127ceb43337Sven Eckelmann if (!strncmp(devname, chan->tag, chan->tag_len) && 6230b20406cda621c2495d10baab1e87127ceb43337Sven Eckelmann strlen(devname) == chan->tag_len) { 624f75580c4afb72c156746b3fc1ec977b1a85d3deeAneesh Kumar K.V if (!chan->inuse) { 625f75580c4afb72c156746b3fc1ec977b1a85d3deeAneesh Kumar K.V chan->inuse = true; 62637c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V found = 1; 627f75580c4afb72c156746b3fc1ec977b1a85d3deeAneesh Kumar K.V break; 628f75580c4afb72c156746b3fc1ec977b1a85d3deeAneesh Kumar K.V } 629c1a7c2262035e83a8f70ebe1328b3451702cf51bAneesh Kumar K.V ret = -EBUSY; 630b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen } 631b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen } 632c1549497e903a1ffa1c5808337a987180e480e7aJosef 'Jeff' Sipek mutex_unlock(&virtio_9p_lock); 633b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 63437c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V if (!found) { 6355d3851530d6d68564e4e0ce04d0547d4d106fc72Joe Perches pr_err("no channels available\n"); 636c1a7c2262035e83a8f70ebe1328b3451702cf51bAneesh Kumar K.V return ret; 637e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen } 638e2735b7720320b68590ca2b32b78ca91213931b2Eric Van Hensbergen 6398b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen client->trans = (void *)chan; 640562ada612058133a5483c68a73605f3c5f42fffeEric Van Hensbergen client->status = Connected; 641fea511a644fb0fb938309c6ab286725ac31b87e2Eric Van Hensbergen chan->client = client; 642b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 6438b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen return 0; 644b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 645b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 646ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen/** 647ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * p9_virtio_remove - clean up resources associated with a virtio device 648ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * @vdev: virtio device to remove 649ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen * 650ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen */ 651ee443996a35c1e04f210cafd43d5a98d41e46085Eric Van Hensbergen 652f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergenstatic void p9_virtio_remove(struct virtio_device *vdev) 653f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen{ 654f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen struct virtio_chan *chan = vdev->priv; 655f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen 656991ad9ec39bd3ecaf08cfb7ea3ef7ae9148e5068Sasha Levin if (chan->inuse) 657991ad9ec39bd3ecaf08cfb7ea3ef7ae9148e5068Sasha Levin p9_virtio_close(chan->client); 65837c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V vdev->config->del_vqs(vdev); 65937c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V 66037c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V mutex_lock(&virtio_9p_lock); 66137c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V list_del(&chan->chan_list); 66237c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V mutex_unlock(&virtio_9p_lock); 66386c8437383acd85c05ec7c9a004f59fe7ac9821aAneesh Kumar K.V sysfs_remove_file(&(vdev->dev.kobj), &dev_attr_mount_tag.attr); 664e0d6cb9cd3a3ac8a3b8e5b22b83c4f8619786f22Michael Marineau kobject_uevent(&(vdev->dev.kobj), KOBJ_CHANGE); 66597ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V kfree(chan->tag); 66652f44e0d08ff1a065bf06615483c608163575cb1Venkateswararao Jujjuri (JV) kfree(chan->vc_wq); 66737c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V kfree(chan); 668f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen 669f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen} 670f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen 671b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenstatic struct virtio_device_id id_table[] = { 672b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen { VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID }, 673b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen { 0 }, 674b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen}; 675b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 67697ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.Vstatic unsigned int features[] = { 67797ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V VIRTIO_9P_MOUNT_TAG, 67897ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V}; 67997ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V 680b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen/* The standard "struct lguest_driver": */ 681b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenstatic struct virtio_driver p9_virtio_drv = { 68297ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .feature_table = features, 68397ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .feature_table_size = ARRAY_SIZE(features), 68497ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .driver.name = KBUILD_MODNAME, 68597ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .driver.owner = THIS_MODULE, 68697ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .id_table = id_table, 68797ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .probe = p9_virtio_probe, 68897ee9b0257402f4731b55dfea42f24d26d793ddfAneesh Kumar K.V .remove = p9_virtio_remove, 689b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen}; 690b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 691b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenstatic struct p9_trans_module p9_virtio_trans = { 692b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen .name = "virtio", 693b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen .create = p9_virtio_create, 6948b81ef589ad1483dd977ef47fe00d4ce4d91a0abEric Van Hensbergen .close = p9_virtio_close, 69591b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen .request = p9_virtio_request, 696dc893e19b5800d7743fb58235877bfa9091805ffArnd Bergmann .zc_request = p9_virtio_zc_request, 69791b8534fa8f5e01f249b1bf8df0a2540053549adEric Van Hensbergen .cancel = p9_virtio_cancel, 698b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V /* 699b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V * We leave one entry for input and one entry for response 700b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V * headers. We also skip one more entry to accomodate, address 701b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V * that are not at page boundary, that can result in an extra 702b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V * page in zero copy. 703b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V */ 704b49d8b5d7007a673796f3f99688b46931293873eAneesh Kumar K.V .maxsize = PAGE_SIZE * (VIRTQUEUE_NUM - 3), 705f94741fd2832e7abc30fbf6dc13ed627c1fcc01aEric Van Hensbergen .def = 1, 70672029fe85d8d060b3f966f2dbc36b3c75b5a6532Tejun Heo .owner = THIS_MODULE, 707b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen}; 708b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 709b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen/* The standard init function */ 710b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenstatic int __init p9_virtio_init(void) 711b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen{ 71237c1209d413242d9560e343c040777049a8dd869Aneesh Kumar K.V INIT_LIST_HEAD(&virtio_chan_list); 713b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 714b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen v9fs_register_trans(&p9_virtio_trans); 715b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen return register_virtio_driver(&p9_virtio_drv); 716b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen} 717b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 718f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergenstatic void __exit p9_virtio_cleanup(void) 719f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen{ 720f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen unregister_virtio_driver(&p9_virtio_drv); 72172029fe85d8d060b3f966f2dbc36b3c75b5a6532Tejun Heo v9fs_unregister_trans(&p9_virtio_trans); 722f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen} 723f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergen 724b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergenmodule_init(p9_virtio_init); 725f39335453fe79f4e12e263e7c6387dc9fb86bfffEric Van Hensbergenmodule_exit(p9_virtio_cleanup); 726b530cc794024be227876a089e66fb17b7b512763Eric Van Hensbergen 727b530cc794024be227876a089e66fb17b7b512763Eric Van HensbergenMODULE_DEVICE_TABLE(virtio, id_table); 728b530cc794024be227876a089e66fb17b7b512763Eric Van HensbergenMODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); 729b530cc794024be227876a089e66fb17b7b512763Eric Van HensbergenMODULE_DESCRIPTION("Virtio 9p Transport"); 730b530cc794024be227876a089e66fb17b7b512763Eric Van HensbergenMODULE_LICENSE("GPL"); 731