Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 1 | /* |
| 2 | * The Guest 9p transport driver |
| 3 | * |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 4 | * This is a block based transport driver based on the lguest block driver |
| 5 | * code. |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 6 | * |
| 7 | */ |
| 8 | /* |
| 9 | * Copyright (C) 2007 Eric Van Hensbergen, IBM Corporation |
| 10 | * |
| 11 | * Based on virtio console driver |
| 12 | * Copyright (C) 2006, 2007 Rusty Russell, IBM Corporation |
| 13 | * |
| 14 | * This program is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU General Public License version 2 |
| 16 | * as published by the Free Software Foundation. |
| 17 | * |
| 18 | * This program is distributed in the hope that it will be useful, |
| 19 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 20 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 21 | * GNU General Public License for more details. |
| 22 | * |
| 23 | * You should have received a copy of the GNU General Public License |
| 24 | * along with this program; if not, write to: |
| 25 | * Free Software Foundation |
| 26 | * 51 Franklin Street, Fifth Floor |
| 27 | * Boston, MA 02111-1301 USA |
| 28 | * |
| 29 | */ |
| 30 | |
| 31 | #include <linux/in.h> |
| 32 | #include <linux/module.h> |
| 33 | #include <linux/net.h> |
| 34 | #include <linux/ipv6.h> |
| 35 | #include <linux/errno.h> |
| 36 | #include <linux/kernel.h> |
| 37 | #include <linux/un.h> |
| 38 | #include <linux/uaccess.h> |
| 39 | #include <linux/inet.h> |
| 40 | #include <linux/idr.h> |
| 41 | #include <linux/file.h> |
| 42 | #include <net/9p/9p.h> |
| 43 | #include <linux/parser.h> |
| 44 | #include <net/9p/transport.h> |
| 45 | #include <linux/scatterlist.h> |
| 46 | #include <linux/virtio.h> |
| 47 | #include <linux/virtio_9p.h> |
| 48 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 49 | #define VIRTQUEUE_NUM 128 |
| 50 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 51 | /* a single mutex to manage channel initialization and attachment */ |
| 52 | static DECLARE_MUTEX(virtio_9p_lock); |
| 53 | /* global which tracks highest initialized channel */ |
| 54 | static int chan_index; |
| 55 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 56 | #define P9_INIT_MAXTAG 16 |
| 57 | |
| 58 | #define REQ_STATUS_IDLE 0 |
| 59 | #define REQ_STATUS_SENT 1 |
| 60 | #define REQ_STATUS_RCVD 2 |
| 61 | #define REQ_STATUS_FLSH 3 |
| 62 | |
| 63 | struct p9_req_t { |
| 64 | int status; |
| 65 | wait_queue_head_t *wq; |
| 66 | }; |
| 67 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 68 | /* We keep all per-channel information in a structure. |
| 69 | * This structure is allocated within the devices dev->mem space. |
| 70 | * A pointer to the structure will get put in the transport private. |
| 71 | */ |
| 72 | static struct virtio_chan { |
| 73 | bool initialized; /* channel is initialized */ |
| 74 | bool inuse; /* channel is in use */ |
| 75 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 76 | spinlock_t lock; |
| 77 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 78 | struct virtio_device *vdev; |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 79 | struct virtqueue *vq; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 80 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 81 | struct p9_idpool *tagpool; |
| 82 | struct p9_req_t *reqs; |
| 83 | int max_tag; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 84 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 85 | /* Scatterlist: can be too big for stack. */ |
| 86 | struct scatterlist sg[VIRTQUEUE_NUM]; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 87 | } channels[MAX_9P_CHAN]; |
| 88 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 89 | /* Lookup requests by tag */ |
| 90 | static struct p9_req_t *p9_lookup_tag(struct virtio_chan *c, u16 tag) |
| 91 | { |
| 92 | /* This looks up the original request by tag so we know which |
| 93 | * buffer to read the data into */ |
| 94 | tag++; |
| 95 | |
| 96 | while (tag >= c->max_tag) { |
| 97 | int old_max = c->max_tag; |
| 98 | int count; |
| 99 | |
| 100 | if (c->max_tag) |
| 101 | c->max_tag *= 2; |
| 102 | else |
| 103 | c->max_tag = P9_INIT_MAXTAG; |
| 104 | |
| 105 | c->reqs = krealloc(c->reqs, sizeof(struct p9_req_t)*c->max_tag, |
| 106 | GFP_ATOMIC); |
| 107 | if (!c->reqs) { |
| 108 | printk(KERN_ERR "Couldn't grow tag array\n"); |
| 109 | BUG(); |
| 110 | } |
| 111 | for (count = old_max; count < c->max_tag; count++) { |
| 112 | c->reqs[count].status = REQ_STATUS_IDLE; |
| 113 | c->reqs[count].wq = kmalloc(sizeof(wait_queue_t), |
| 114 | GFP_ATOMIC); |
| 115 | if (!c->reqs[count].wq) { |
| 116 | printk(KERN_ERR "Couldn't grow tag array\n"); |
| 117 | BUG(); |
| 118 | } |
| 119 | init_waitqueue_head(c->reqs[count].wq); |
| 120 | } |
| 121 | } |
| 122 | |
| 123 | return &c->reqs[tag]; |
| 124 | } |
| 125 | |
| 126 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 127 | /* How many bytes left in this page. */ |
| 128 | static unsigned int rest_of_page(void *data) |
| 129 | { |
| 130 | return PAGE_SIZE - ((unsigned long)data % PAGE_SIZE); |
| 131 | } |
| 132 | |
| 133 | static int p9_virtio_write(struct p9_trans *trans, void *buf, int count) |
| 134 | { |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 135 | /* Only use the rpc mechanism for now */ |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 136 | return count; |
| 137 | } |
| 138 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 139 | static int p9_virtio_read(struct p9_trans *trans, void *buf, int count) |
| 140 | { |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 141 | /* Only use the rpc mechanism for now */ |
| 142 | return 0; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 143 | } |
| 144 | |
| 145 | /* The poll function is used by 9p transports to determine if there |
| 146 | * is there is activity available on a particular channel. In our case |
| 147 | * we use it to wait for a callback from the input routines. |
| 148 | */ |
| 149 | static unsigned int |
| 150 | p9_virtio_poll(struct p9_trans *trans, struct poll_table_struct *pt) |
| 151 | { |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 152 | /* Only use the rpc mechanism for now */ |
| 153 | return 0; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 154 | } |
| 155 | |
| 156 | static void p9_virtio_close(struct p9_trans *trans) |
| 157 | { |
| 158 | struct virtio_chan *chan = trans->priv; |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 159 | int count; |
| 160 | unsigned int flags; |
| 161 | |
| 162 | spin_lock_irqsave(&chan->lock, flags); |
| 163 | p9_idpool_destroy(chan->tagpool); |
| 164 | for (count = 0; count < chan->max_tag; count++) |
| 165 | kfree(chan->reqs[count].wq); |
| 166 | kfree(chan->reqs); |
| 167 | chan->max_tag = 0; |
| 168 | spin_unlock_irqrestore(&chan->lock, flags); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 169 | |
| 170 | down(&virtio_9p_lock); |
| 171 | chan->inuse = false; |
| 172 | up(&virtio_9p_lock); |
| 173 | |
| 174 | kfree(trans); |
| 175 | } |
| 176 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 177 | static void req_done(struct virtqueue *vq) |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 178 | { |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 179 | struct virtio_chan *chan = vq->vdev->priv; |
| 180 | struct p9_fcall *rc; |
| 181 | unsigned int len; |
| 182 | unsigned long flags; |
| 183 | struct p9_req_t *req; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 184 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 185 | spin_lock_irqsave(&chan->lock, flags); |
| 186 | while ((rc = chan->vq->vq_ops->get_buf(chan->vq, &len)) != NULL) { |
| 187 | req = p9_lookup_tag(chan, rc->tag); |
| 188 | req->status = REQ_STATUS_RCVD; |
| 189 | wake_up(req->wq); |
| 190 | } |
| 191 | /* In case queue is stopped waiting for more buffers. */ |
| 192 | spin_unlock_irqrestore(&chan->lock, flags); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 193 | } |
| 194 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 195 | static int |
| 196 | pack_sg_list(struct scatterlist *sg, int start, int limit, char *data, |
| 197 | int count) |
| 198 | { |
| 199 | int s; |
| 200 | int index = start; |
| 201 | |
| 202 | while (count) { |
| 203 | s = rest_of_page(data); |
| 204 | if (s > count) |
| 205 | s = count; |
| 206 | sg_set_buf(&sg[index++], data, s); |
| 207 | count -= s; |
| 208 | data += s; |
| 209 | if (index > limit) |
| 210 | BUG(); |
| 211 | } |
| 212 | |
| 213 | return index-start; |
| 214 | } |
| 215 | |
| 216 | static int |
| 217 | p9_virtio_rpc(struct p9_trans *t, struct p9_fcall *tc, struct p9_fcall **rc, |
| 218 | int msize, int dotu) |
| 219 | { |
| 220 | int in, out; |
| 221 | int n, err, size; |
| 222 | struct virtio_chan *chan = t->priv; |
| 223 | char *rdata; |
| 224 | struct p9_req_t *req; |
| 225 | unsigned long flags; |
| 226 | |
| 227 | if (*rc == NULL) { |
| 228 | *rc = kmalloc(sizeof(struct p9_fcall) + msize, GFP_KERNEL); |
| 229 | if (!*rc) |
| 230 | return -ENOMEM; |
| 231 | } |
| 232 | |
| 233 | rdata = (char *)*rc+sizeof(struct p9_fcall); |
| 234 | |
| 235 | spin_lock_irqsave(&chan->lock, flags); |
| 236 | n = P9_NOTAG; |
| 237 | if (tc->id != P9_TVERSION) { |
| 238 | n = p9_idpool_get(chan->tagpool); |
| 239 | if (n < 0) |
| 240 | return -ENOMEM; |
| 241 | } |
| 242 | |
| 243 | req = p9_lookup_tag(chan, n); |
| 244 | spin_unlock_irqrestore(&chan->lock, flags); |
| 245 | |
| 246 | p9_set_tag(tc, n); |
| 247 | |
| 248 | P9_DPRINTK(P9_DEBUG_TRANS, "9p debug: virtio rpc tag %d\n", n); |
| 249 | |
| 250 | out = pack_sg_list(chan->sg, 0, VIRTQUEUE_NUM, tc->sdata, tc->size); |
| 251 | in = pack_sg_list(chan->sg, out, VIRTQUEUE_NUM-out, rdata, msize); |
| 252 | |
| 253 | req->status = REQ_STATUS_SENT; |
| 254 | |
| 255 | if (chan->vq->vq_ops->add_buf(chan->vq, chan->sg, out, in, tc)) { |
| 256 | P9_DPRINTK(P9_DEBUG_TRANS, |
| 257 | "9p debug: virtio rpc add_buf returned failure"); |
| 258 | return -EIO; |
| 259 | } |
| 260 | |
| 261 | chan->vq->vq_ops->kick(chan->vq); |
| 262 | |
| 263 | wait_event(*req->wq, req->status == REQ_STATUS_RCVD); |
| 264 | |
| 265 | size = le32_to_cpu(*(__le32 *) rdata); |
| 266 | |
| 267 | err = p9_deserialize_fcall(rdata, size, *rc, dotu); |
| 268 | if (err < 0) { |
| 269 | P9_DPRINTK(P9_DEBUG_TRANS, |
| 270 | "9p debug: virtio rpc deserialize returned %d\n", err); |
| 271 | return err; |
| 272 | } |
| 273 | |
| 274 | #ifdef CONFIG_NET_9P_DEBUG |
| 275 | if ((p9_debug_level&P9_DEBUG_FCALL) == P9_DEBUG_FCALL) { |
| 276 | char buf[150]; |
| 277 | |
| 278 | p9_printfcall(buf, sizeof(buf), *rc, dotu); |
| 279 | printk(KERN_NOTICE ">>> %p %s\n", t, buf); |
| 280 | } |
| 281 | #endif |
| 282 | |
| 283 | if (n != P9_NOTAG && p9_idpool_check(n, chan->tagpool)) |
| 284 | p9_idpool_put(n, chan->tagpool); |
| 285 | |
| 286 | req->status = REQ_STATUS_IDLE; |
| 287 | |
| 288 | return 0; |
| 289 | } |
| 290 | |
| 291 | static int p9_virtio_probe(struct virtio_device *vdev) |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 292 | { |
| 293 | int err; |
| 294 | struct virtio_chan *chan; |
| 295 | int index; |
| 296 | |
| 297 | down(&virtio_9p_lock); |
| 298 | index = chan_index++; |
| 299 | chan = &channels[index]; |
| 300 | up(&virtio_9p_lock); |
| 301 | |
| 302 | if (chan_index > MAX_9P_CHAN) { |
| 303 | printk(KERN_ERR "9p: virtio: Maximum channels exceeded\n"); |
| 304 | BUG(); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 305 | err = -ENOMEM; |
| 306 | goto fail; |
| 307 | } |
| 308 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 309 | chan->vdev = vdev; |
| 310 | |
| 311 | /* We expect one virtqueue, for requests. */ |
| 312 | chan->vq = vdev->config->find_vq(vdev, 0, req_done); |
| 313 | if (IS_ERR(chan->vq)) { |
| 314 | err = PTR_ERR(chan->vq); |
| 315 | goto out_free_vq; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 316 | } |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 317 | chan->vq->vdev->priv = chan; |
| 318 | spin_lock_init(&chan->lock); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 319 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 320 | sg_init_table(chan->sg, VIRTQUEUE_NUM); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 321 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 322 | chan->inuse = false; |
| 323 | chan->initialized = true; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 324 | return 0; |
| 325 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 326 | out_free_vq: |
| 327 | vdev->config->del_vq(chan->vq); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 328 | fail: |
| 329 | down(&virtio_9p_lock); |
| 330 | chan_index--; |
| 331 | up(&virtio_9p_lock); |
| 332 | return err; |
| 333 | } |
| 334 | |
| 335 | /* This sets up a transport channel for 9p communication. Right now |
| 336 | * we only match the first available channel, but eventually we couldlook up |
| 337 | * alternate channels by matching devname versus a virtio_config entry. |
| 338 | * We use a simple reference count mechanism to ensure that only a single |
| 339 | * mount has a channel open at a time. */ |
| 340 | static struct p9_trans *p9_virtio_create(const char *devname, char *args) |
| 341 | { |
| 342 | struct p9_trans *trans; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 343 | struct virtio_chan *chan = channels; |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 344 | int index = 0; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 345 | |
| 346 | down(&virtio_9p_lock); |
| 347 | while (index < MAX_9P_CHAN) { |
| 348 | if (chan->initialized && !chan->inuse) { |
| 349 | chan->inuse = true; |
| 350 | break; |
| 351 | } else { |
| 352 | index++; |
| 353 | chan = &channels[index]; |
| 354 | } |
| 355 | } |
| 356 | up(&virtio_9p_lock); |
| 357 | |
| 358 | if (index >= MAX_9P_CHAN) { |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 359 | printk(KERN_ERR "9p: no channels available\n"); |
| 360 | return ERR_PTR(-ENODEV); |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 361 | } |
| 362 | |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 363 | chan->tagpool = p9_idpool_create(); |
| 364 | if (IS_ERR(chan->tagpool)) { |
| 365 | printk(KERN_ERR "9p: couldn't allocate tagpool\n"); |
| 366 | return ERR_PTR(-ENOMEM); |
| 367 | } |
| 368 | p9_idpool_get(chan->tagpool); /* reserve tag 0 */ |
| 369 | chan->max_tag = 0; |
| 370 | chan->reqs = NULL; |
| 371 | |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 372 | trans = kmalloc(sizeof(struct p9_trans), GFP_KERNEL); |
| 373 | if (!trans) { |
| 374 | printk(KERN_ERR "9p: couldn't allocate transport\n"); |
| 375 | return ERR_PTR(-ENOMEM); |
| 376 | } |
| 377 | |
| 378 | trans->write = p9_virtio_write; |
| 379 | trans->read = p9_virtio_read; |
| 380 | trans->close = p9_virtio_close; |
| 381 | trans->poll = p9_virtio_poll; |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 382 | trans->rpc = p9_virtio_rpc; |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 383 | trans->priv = chan; |
| 384 | |
| 385 | return trans; |
| 386 | } |
| 387 | |
| 388 | #define VIRTIO_ID_9P 9 |
| 389 | |
| 390 | static struct virtio_device_id id_table[] = { |
| 391 | { VIRTIO_ID_9P, VIRTIO_DEV_ANY_ID }, |
| 392 | { 0 }, |
| 393 | }; |
| 394 | |
| 395 | /* The standard "struct lguest_driver": */ |
| 396 | static struct virtio_driver p9_virtio_drv = { |
| 397 | .driver.name = KBUILD_MODNAME, |
| 398 | .driver.owner = THIS_MODULE, |
| 399 | .id_table = id_table, |
| 400 | .probe = p9_virtio_probe, |
| 401 | }; |
| 402 | |
| 403 | static struct p9_trans_module p9_virtio_trans = { |
| 404 | .name = "virtio", |
| 405 | .create = p9_virtio_create, |
Eric Van Hensbergen | e2735b7 | 2008-02-06 19:25:58 -0600 | [diff] [blame^] | 406 | .maxsize = PAGE_SIZE*16, |
Eric Van Hensbergen | b530cc7 | 2007-10-23 13:47:31 -0500 | [diff] [blame] | 407 | .def = 0, |
| 408 | }; |
| 409 | |
| 410 | /* The standard init function */ |
| 411 | static int __init p9_virtio_init(void) |
| 412 | { |
| 413 | int count; |
| 414 | |
| 415 | for (count = 0; count < MAX_9P_CHAN; count++) |
| 416 | channels[count].initialized = false; |
| 417 | |
| 418 | v9fs_register_trans(&p9_virtio_trans); |
| 419 | return register_virtio_driver(&p9_virtio_drv); |
| 420 | } |
| 421 | |
| 422 | module_init(p9_virtio_init); |
| 423 | |
| 424 | MODULE_DEVICE_TABLE(virtio, id_table); |
| 425 | MODULE_AUTHOR("Eric Van Hensbergen <ericvh@gmail.com>"); |
| 426 | MODULE_DESCRIPTION("Virtio 9p Transport"); |
| 427 | MODULE_LICENSE("GPL"); |