drivers/misc/mic/host/mic_virtio.c

   1 /*
   2  * Intel MIC Platform Software Stack (MPSS)
   3  *
   4  * Copyright(c) 2013 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License, version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  13  * General Public License for more details.
  14  *
  15  * The full GNU General Public License is included in this distribution in
  16  * the file called "COPYING".
  17  *
  18  * Intel MIC Host driver.
  19  *
  20  */
  21 #include <linux/pci.h>
  22 #include <linux/sched.h>
  23 #include <linux/uaccess.h>
  24 #include <linux/dmaengine.h>
  25 #include <linux/mic_common.h>
  26
  27 #include "../common/mic_dev.h"
  28 #include "mic_device.h"
  29 #include "mic_smpt.h"
  30 #include "mic_virtio.h"
  31
  32 /*
  33  * Size of the internal buffer used during DMA's as an intermediate buffer
  34  * for copy to/from user.
  35  */
  36 #define MIC_INT_DMA_BUF_SIZE PAGE_ALIGN(64 * 1024ULL)
  37
  38 static int mic_sync_dma(struct mic_device *mdev, dma_addr_t dst,
  39                         dma_addr_t src, size_t len)
  40 {
  41         int err = 0;
  42         struct dma_async_tx_descriptor *tx;
  43         struct dma_chan *mic_ch = mdev->dma_ch[0];
  44
  45         if (!mic_ch) {
  46                 err = -EBUSY;
  47                 goto error;
  48         }
  49
  50         tx = mic_ch->device->device_prep_dma_memcpy(mic_ch, dst, src, len,
  51                                                     DMA_PREP_FENCE);
  52         if (!tx) {
  53                 err = -ENOMEM;
  54                 goto error;
  55         } else {
  56                 dma_cookie_t cookie = tx->tx_submit(tx);
  57
  58                 err = dma_submit_error(cookie);
  59                 if (err)
  60                         goto error;
  61                 err = dma_sync_wait(mic_ch, cookie);
  62         }
  63 error:
  64         if (err)
  65                 dev_err(mdev->sdev->parent, "%s %d err %d\n",
  66                         __func__, __LINE__, err);
  67         return err;
  68 }
  69
  70 /*
  71  * Initiates the copies across the PCIe bus from card memory to a user
  72  * space buffer. When transfers are done using DMA, source/destination
  73  * addresses and transfer length must follow the alignment requirements of
  74  * the MIC DMA engine.
  75  */
  76 static int mic_virtio_copy_to_user(struct mic_vdev *mvdev, void __user *ubuf,
  77                                    size_t len, u64 daddr, size_t dlen,
  78                                    int vr_idx)
  79 {
  80         struct mic_device *mdev = mvdev->mdev;
  81         void __iomem *dbuf = mdev->aper.va + daddr;
  82         struct mic_vringh *mvr = &mvdev->mvr[vr_idx];
  83         size_t dma_alignment = 1 << mdev->dma_ch[0]->device->copy_align;
  84         size_t dma_offset;
  85         size_t partlen;
  86         int err;
  87
  88         dma_offset = daddr - round_down(daddr, dma_alignment);
  89         daddr -= dma_offset;
  90         len += dma_offset;
  91
  92         while (len) {
  93                 partlen = min_t(size_t, len, MIC_INT_DMA_BUF_SIZE);
  94
  95                 err = mic_sync_dma(mdev, mvr->buf_da, daddr,
  96                                    ALIGN(partlen, dma_alignment));
  97                 if (err)
  98                         goto err;
  99
 100                 if (copy_to_user(ubuf, mvr->buf + dma_offset,
 101                                  partlen - dma_offset)) {
 102                         err = -EFAULT;
 103                         goto err;
 104                 }
 105                 daddr += partlen;
 106                 ubuf += partlen;
 107                 dbuf += partlen;
 108                 mvdev->in_bytes_dma += partlen;
 109                 mvdev->in_bytes += partlen;
 110                 len -= partlen;
 111                 dma_offset = 0;
 112         }
 113         return 0;
 114 err:
 115         dev_err(mic_dev(mvdev), "%s %d err %d\n", __func__, __LINE__, err);
 116         return err;
 117 }
 118
 119 /*
 120  * Initiates copies across the PCIe bus from a user space buffer to card
 121  * memory. When transfers are done using DMA, source/destination addresses
 122  * and transfer length must follow the alignment requirements of the MIC
 123  * DMA engine.
 124  */
 125 static int mic_virtio_copy_from_user(struct mic_vdev *mvdev, void __user *ubuf,
 126                                      size_t len, u64 daddr, size_t dlen,
 127                                      int vr_idx)
 128 {
 129         struct mic_device *mdev = mvdev->mdev;
 130         void __iomem *dbuf = mdev->aper.va + daddr;
 131         struct mic_vringh *mvr = &mvdev->mvr[vr_idx];
 132         size_t dma_alignment = 1 << mdev->dma_ch[0]->device->copy_align;
 133         size_t partlen;
 134         int err;
 135
 136         if (daddr & (dma_alignment - 1)) {
 137                 mvdev->tx_dst_unaligned += len;
 138                 goto memcpy;
 139         } else if (ALIGN(len, dma_alignment) > dlen) {
 140                 mvdev->tx_len_unaligned += len;
 141                 goto memcpy;
 142         }
 143
 144         while (len) {
 145                 partlen = min_t(size_t, len, MIC_INT_DMA_BUF_SIZE);
 146
 147                 if (copy_from_user(mvr->buf, ubuf, partlen)) {
 148                         err = -EFAULT;
 149                         goto err;
 150                 }
 151                 err = mic_sync_dma(mdev, daddr, mvr->buf_da,
 152                                    ALIGN(partlen, dma_alignment));
 153                 if (err)
 154                         goto err;
 155                 daddr += partlen;
 156                 ubuf += partlen;
 157                 dbuf += partlen;
 158                 mvdev->out_bytes_dma += partlen;
 159                 mvdev->out_bytes += partlen;
 160                 len -= partlen;
 161         }
 162 memcpy:
 163         /*
 164          * We are copying to IO below and should ideally use something
 165          * like copy_from_user_toio(..) if it existed.
 166          */
 167         if (copy_from_user((void __force *)dbuf, ubuf, len)) {
 168                 err = -EFAULT;
 169                 goto err;
 170         }
 171         mvdev->out_bytes += len;
 172         return 0;
 173 err:
 174         dev_err(mic_dev(mvdev), "%s %d err %d\n", __func__, __LINE__, err);
 175         return err;
 176 }
 177
 178 #define MIC_VRINGH_READ true
 179
 180 /* The function to call to notify the card about added buffers */
 181 static void mic_notify(struct vringh *vrh)
 182 {
 183         struct mic_vringh *mvrh = container_of(vrh, struct mic_vringh, vrh);
 184         struct mic_vdev *mvdev = mvrh->mvdev;
 185         s8 db = mvdev->dc->h2c_vdev_db;
 186
 187         if (db != -1)
 188                 mvdev->mdev->ops->send_intr(mvdev->mdev, db);
 189 }
 190
 191 /* Determine the total number of bytes consumed in a VRINGH KIOV */
 192 static inline u32 mic_vringh_iov_consumed(struct vringh_kiov *iov)
 193 {
 194         int i;
 195         u32 total = iov->consumed;
 196
 197         for (i = 0; i < iov->i; i++)
 198                 total += iov->iov[i].iov_len;
 199         return total;
 200 }
 201
 202 /*
 203  * Traverse the VRINGH KIOV and issue the APIs to trigger the copies.
 204  * This API is heavily based on the vringh_iov_xfer(..) implementation
 205  * in vringh.c. The reason we cannot reuse vringh_iov_pull_kern(..)
 206  * and vringh_iov_push_kern(..) directly is because there is no
 207  * way to override the VRINGH xfer(..) routines as of v3.10.
 208  */
 209 static int mic_vringh_copy(struct mic_vdev *mvdev, struct vringh_kiov *iov,
 210                         void __user *ubuf, size_t len, bool read, int vr_idx,
 211                         size_t *out_len)
 212 {
 213         int ret = 0;
 214         size_t partlen, tot_len = 0;
 215
 216         while (len && iov->i < iov->used) {
 217                 partlen = min(iov->iov[iov->i].iov_len, len);
 218                 if (read)
 219                         ret = mic_virtio_copy_to_user(mvdev, ubuf, partlen,
 220                                                 (u64)iov->iov[iov->i].iov_base,
 221                                                 iov->iov[iov->i].iov_len,
 222                                                 vr_idx);
 223                 else
 224                         ret = mic_virtio_copy_from_user(mvdev, ubuf, partlen,
 225                                                 (u64)iov->iov[iov->i].iov_base,
 226                                                 iov->iov[iov->i].iov_len,
 227                                                 vr_idx);
 228                 if (ret) {
 229                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 230                                 __func__, __LINE__, ret);
 231                         break;
 232                 }
 233                 len -= partlen;
 234                 ubuf += partlen;
 235                 tot_len += partlen;
 236                 iov->consumed += partlen;
 237                 iov->iov[iov->i].iov_len -= partlen;
 238                 iov->iov[iov->i].iov_base += partlen;
 239                 if (!iov->iov[iov->i].iov_len) {
 240                         /* Fix up old iov element then increment. */
 241                         iov->iov[iov->i].iov_len = iov->consumed;
 242                         iov->iov[iov->i].iov_base -= iov->consumed;
 243
 244                         iov->consumed = 0;
 245                         iov->i++;
 246                 }
 247         }
 248         *out_len = tot_len;
 249         return ret;
 250 }
 251
 252 /*
 253  * Use the standard VRINGH infrastructure in the kernel to fetch new
 254  * descriptors, initiate the copies and update the used ring.
 255  */
 256 static int _mic_virtio_copy(struct mic_vdev *mvdev,
 257         struct mic_copy_desc *copy)
 258 {
 259         int ret = 0;
 260         u32 iovcnt = copy->iovcnt;
 261         struct iovec iov;
 262         struct iovec __user *u_iov = copy->iov;
 263         void __user *ubuf = NULL;
 264         struct mic_vringh *mvr = &mvdev->mvr[copy->vr_idx];
 265         struct vringh_kiov *riov = &mvr->riov;
 266         struct vringh_kiov *wiov = &mvr->wiov;
 267         struct vringh *vrh = &mvr->vrh;
 268         u16 *head = &mvr->head;
 269         struct mic_vring *vr = &mvr->vring;
 270         size_t len = 0, out_len;
 271
 272         copy->out_len = 0;
 273         /* Fetch a new IOVEC if all previous elements have been processed */
 274         if (riov->i == riov->used && wiov->i == wiov->used) {
 275                 ret = vringh_getdesc_kern(vrh, riov, wiov,
 276                                 head, GFP_KERNEL);
 277                 /* Check if there are available descriptors */
 278                 if (ret <= 0)
 279                         return ret;
 280         }
 281         while (iovcnt) {
 282                 if (!len) {
 283                         /* Copy over a new iovec from user space. */
 284                         ret = copy_from_user(&iov, u_iov, sizeof(*u_iov));
 285                         if (ret) {
 286                                 ret = -EINVAL;
 287                                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 288                                         __func__, __LINE__, ret);
 289                                 break;
 290                         }
 291                         len = iov.iov_len;
 292                         ubuf = iov.iov_base;
 293                 }
 294                 /* Issue all the read descriptors first */
 295                 ret = mic_vringh_copy(mvdev, riov, ubuf, len, MIC_VRINGH_READ,
 296                                       copy->vr_idx, &out_len);
 297                 if (ret) {
 298                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 299                                 __func__, __LINE__, ret);
 300                         break;
 301                 }
 302                 len -= out_len;
 303                 ubuf += out_len;
 304                 copy->out_len += out_len;
 305                 /* Issue the write descriptors next */
 306                 ret = mic_vringh_copy(mvdev, wiov, ubuf, len, !MIC_VRINGH_READ,
 307                                       copy->vr_idx, &out_len);
 308                 if (ret) {
 309                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 310                                 __func__, __LINE__, ret);
 311                         break;
 312                 }
 313                 len -= out_len;
 314                 ubuf += out_len;
 315                 copy->out_len += out_len;
 316                 if (!len) {
 317                         /* One user space iovec is now completed */
 318                         iovcnt--;
 319                         u_iov++;
 320                 }
 321                 /* Exit loop if all elements in KIOVs have been processed. */
 322                 if (riov->i == riov->used && wiov->i == wiov->used)
 323                         break;
 324         }
 325         /*
 326          * Update the used ring if a descriptor was available and some data was
 327          * copied in/out and the user asked for a used ring update.
 328          */
 329         if (*head != USHRT_MAX && copy->out_len && copy->update_used) {
 330                 u32 total = 0;
 331
 332                 /* Determine the total data consumed */
 333                 total += mic_vringh_iov_consumed(riov);
 334                 total += mic_vringh_iov_consumed(wiov);
 335                 vringh_complete_kern(vrh, *head, total);
 336                 *head = USHRT_MAX;
 337                 if (vringh_need_notify_kern(vrh) > 0)
 338                         vringh_notify(vrh);
 339                 vringh_kiov_cleanup(riov);
 340                 vringh_kiov_cleanup(wiov);
 341                 /* Update avail idx for user space */
 342                 vr->info->avail_idx = vrh->last_avail_idx;
 343         }
 344         return ret;
 345 }
 346
 347 static inline int mic_verify_copy_args(struct mic_vdev *mvdev,
 348                 struct mic_copy_desc *copy)
 349 {
 350         if (copy->vr_idx >= mvdev->dd->num_vq) {
 351                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 352                         __func__, __LINE__, -EINVAL);
 353                 return -EINVAL;
 354         }
 355         return 0;
 356 }
 357
 358 /* Copy a specified number of virtio descriptors in a chain */
 359 int mic_virtio_copy_desc(struct mic_vdev *mvdev,
 360                 struct mic_copy_desc *copy)
 361 {
 362         int err;
 363         struct mic_vringh *mvr = &mvdev->mvr[copy->vr_idx];
 364
 365         err = mic_verify_copy_args(mvdev, copy);
 366         if (err)
 367                 return err;
 368
 369         mutex_lock(&mvr->vr_mutex);
 370         if (!mic_vdevup(mvdev)) {
 371                 err = -ENODEV;
 372                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 373                         __func__, __LINE__, err);
 374                 goto err;
 375         }
 376         err = _mic_virtio_copy(mvdev, copy);
 377         if (err) {
 378                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 379                         __func__, __LINE__, err);
 380         }
 381 err:
 382         mutex_unlock(&mvr->vr_mutex);
 383         return err;
 384 }
 385
 386 static void mic_virtio_init_post(struct mic_vdev *mvdev)
 387 {
 388         struct mic_vqconfig *vqconfig = mic_vq_config(mvdev->dd);
 389         int i;
 390
 391         for (i = 0; i < mvdev->dd->num_vq; i++) {
 392                 if (!le64_to_cpu(vqconfig[i].used_address)) {
 393                         dev_warn(mic_dev(mvdev), "used_address zero??\n");
 394                         continue;
 395                 }
 396                 mvdev->mvr[i].vrh.vring.used =
 397                         (void __force *)mvdev->mdev->aper.va +
 398                         le64_to_cpu(vqconfig[i].used_address);
 399         }
 400
 401         mvdev->dc->used_address_updated = 0;
 402
 403         dev_dbg(mic_dev(mvdev), "%s: device type %d LINKUP\n",
 404                 __func__, mvdev->virtio_id);
 405 }
 406
 407 static inline void mic_virtio_device_reset(struct mic_vdev *mvdev)
 408 {
 409         int i;
 410
 411         dev_dbg(mic_dev(mvdev), "%s: status %d device type %d RESET\n",
 412                 __func__, mvdev->dd->status, mvdev->virtio_id);
 413
 414         for (i = 0; i < mvdev->dd->num_vq; i++)
 415                 /*
 416                  * Avoid lockdep false positive. The + 1 is for the mic
 417                  * mutex which is held in the reset devices code path.
 418                  */
 419                 mutex_lock_nested(&mvdev->mvr[i].vr_mutex, i + 1);
 420
 421         /* 0 status means "reset" */
 422         mvdev->dd->status = 0;
 423         mvdev->dc->vdev_reset = 0;
 424         mvdev->dc->host_ack = 1;
 425
 426         for (i = 0; i < mvdev->dd->num_vq; i++) {
 427                 struct vringh *vrh = &mvdev->mvr[i].vrh;
 428                 mvdev->mvr[i].vring.info->avail_idx = 0;
 429                 vrh->completed = 0;
 430                 vrh->last_avail_idx = 0;
 431                 vrh->last_used_idx = 0;
 432         }
 433
 434         for (i = 0; i < mvdev->dd->num_vq; i++)
 435                 mutex_unlock(&mvdev->mvr[i].vr_mutex);
 436 }
 437
 438 void mic_virtio_reset_devices(struct mic_device *mdev)
 439 {
 440         struct list_head *pos, *tmp;
 441         struct mic_vdev *mvdev;
 442
 443         dev_dbg(mdev->sdev->parent, "%s\n",  __func__);
 444
 445         list_for_each_safe(pos, tmp, &mdev->vdev_list) {
 446                 mvdev = list_entry(pos, struct mic_vdev, list);
 447                 mic_virtio_device_reset(mvdev);
 448                 mvdev->poll_wake = 1;
 449                 wake_up(&mvdev->waitq);
 450         }
 451 }
 452
 453 void mic_bh_handler(struct work_struct *work)
 454 {
 455         struct mic_vdev *mvdev = container_of(work, struct mic_vdev,
 456                         virtio_bh_work);
 457
 458         if (mvdev->dc->used_address_updated)
 459                 mic_virtio_init_post(mvdev);
 460
 461         if (mvdev->dc->vdev_reset)
 462                 mic_virtio_device_reset(mvdev);
 463
 464         mvdev->poll_wake = 1;
 465         wake_up(&mvdev->waitq);
 466 }
 467
 468 static irqreturn_t mic_virtio_intr_handler(int irq, void *data)
 469 {
 470         struct mic_vdev *mvdev = data;
 471         struct mic_device *mdev = mvdev->mdev;
 472
 473         mdev->ops->intr_workarounds(mdev);
 474         schedule_work(&mvdev->virtio_bh_work);
 475         return IRQ_HANDLED;
 476 }
 477
 478 int mic_virtio_config_change(struct mic_vdev *mvdev,
 479                         void __user *argp)
 480 {
 481         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
 482         int ret = 0, retry, i;
 483         struct mic_bootparam *bootparam = mvdev->mdev->dp;
 484         s8 db = bootparam->h2c_config_db;
 485
 486         mutex_lock(&mvdev->mdev->mic_mutex);
 487         for (i = 0; i < mvdev->dd->num_vq; i++)
 488                 mutex_lock_nested(&mvdev->mvr[i].vr_mutex, i + 1);
 489
 490         if (db == -1 || mvdev->dd->type == -1) {
 491                 ret = -EIO;
 492                 goto exit;
 493         }
 494
 495         if (copy_from_user(mic_vq_configspace(mvdev->dd),
 496                            argp, mvdev->dd->config_len)) {
 497                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 498                         __func__, __LINE__, -EFAULT);
 499                 ret = -EFAULT;
 500                 goto exit;
 501         }
 502         mvdev->dc->config_change = MIC_VIRTIO_PARAM_CONFIG_CHANGED;
 503         mvdev->mdev->ops->send_intr(mvdev->mdev, db);
 504
 505         for (retry = 100; retry--;) {
 506                 ret = wait_event_timeout(wake,
 507                         mvdev->dc->guest_ack, msecs_to_jiffies(100));
 508                 if (ret)
 509                         break;
 510         }
 511
 512         dev_dbg(mic_dev(mvdev),
 513                 "%s %d retry: %d\n", __func__, __LINE__, retry);
 514         mvdev->dc->config_change = 0;
 515         mvdev->dc->guest_ack = 0;
 516 exit:
 517         for (i = 0; i < mvdev->dd->num_vq; i++)
 518                 mutex_unlock(&mvdev->mvr[i].vr_mutex);
 519         mutex_unlock(&mvdev->mdev->mic_mutex);
 520         return ret;
 521 }
 522
 523 static int mic_copy_dp_entry(struct mic_vdev *mvdev,
 524                                         void __user *argp,
 525                                         __u8 *type,
 526                                         struct mic_device_desc **devpage)
 527 {
 528         struct mic_device *mdev = mvdev->mdev;
 529         struct mic_device_desc dd, *dd_config, *devp;
 530         struct mic_vqconfig *vqconfig;
 531         int ret = 0, i;
 532         bool slot_found = false;
 533
 534         if (copy_from_user(&dd, argp, sizeof(dd))) {
 535                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 536                         __func__, __LINE__, -EFAULT);
 537                 return -EFAULT;
 538         }
 539
 540         if (mic_aligned_desc_size(&dd) > MIC_MAX_DESC_BLK_SIZE ||
 541             dd.num_vq > MIC_MAX_VRINGS) {
 542                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 543                         __func__, __LINE__, -EINVAL);
 544                 return -EINVAL;
 545         }
 546
 547         dd_config = kmalloc(mic_desc_size(&dd), GFP_KERNEL);
 548         if (dd_config == NULL) {
 549                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 550                         __func__, __LINE__, -ENOMEM);
 551                 return -ENOMEM;
 552         }
 553         if (copy_from_user(dd_config, argp, mic_desc_size(&dd))) {
 554                 ret = -EFAULT;
 555                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 556                         __func__, __LINE__, ret);
 557                 goto exit;
 558         }
 559
 560         vqconfig = mic_vq_config(dd_config);
 561         for (i = 0; i < dd.num_vq; i++) {
 562                 if (le16_to_cpu(vqconfig[i].num) > MIC_MAX_VRING_ENTRIES) {
 563                         ret =  -EINVAL;
 564                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 565                                 __func__, __LINE__, ret);
 566                         goto exit;
 567                 }
 568         }
 569
 570         /* Find the first free device page entry */
 571         for (i = sizeof(struct mic_bootparam);
 572                 i < MIC_DP_SIZE - mic_total_desc_size(dd_config);
 573                 i += mic_total_desc_size(devp)) {
 574                 devp = mdev->dp + i;
 575                 if (devp->type == 0 || devp->type == -1) {
 576                         slot_found = true;
 577                         break;
 578                 }
 579         }
 580         if (!slot_found) {
 581                 ret =  -EINVAL;
 582                 dev_err(mic_dev(mvdev), "%s %d err %d\n",
 583                         __func__, __LINE__, ret);
 584                 goto exit;
 585         }
 586         /*
 587          * Save off the type before doing the memcpy. Type will be set in the
 588          * end after completing all initialization for the new device.
 589          */
 590         *type = dd_config->type;
 591         dd_config->type = 0;
 592         memcpy(devp, dd_config, mic_desc_size(dd_config));
 593
 594         *devpage = devp;
 595 exit:
 596         kfree(dd_config);
 597         return ret;
 598 }
 599
 600 static void mic_init_device_ctrl(struct mic_vdev *mvdev,
 601                                 struct mic_device_desc *devpage)
 602 {
 603         struct mic_device_ctrl *dc;
 604
 605         dc = (void *)devpage + mic_aligned_desc_size(devpage);
 606
 607         dc->config_change = 0;
 608         dc->guest_ack = 0;
 609         dc->vdev_reset = 0;
 610         dc->host_ack = 0;
 611         dc->used_address_updated = 0;
 612         dc->c2h_vdev_db = -1;
 613         dc->h2c_vdev_db = -1;
 614         mvdev->dc = dc;
 615 }
 616
 617 int mic_virtio_add_device(struct mic_vdev *mvdev,
 618                         void __user *argp)
 619 {
 620         struct mic_device *mdev = mvdev->mdev;
 621         struct mic_device_desc *dd = NULL;
 622         struct mic_vqconfig *vqconfig;
 623         int vr_size, i, j, ret;
 624         u8 type = 0;
 625         s8 db;
 626         char irqname[10];
 627         struct mic_bootparam *bootparam = mdev->dp;
 628         u16 num;
 629         dma_addr_t vr_addr;
 630
 631         mutex_lock(&mdev->mic_mutex);
 632
 633         ret = mic_copy_dp_entry(mvdev, argp, &type, &dd);
 634         if (ret) {
 635                 mutex_unlock(&mdev->mic_mutex);
 636                 return ret;
 637         }
 638
 639         mic_init_device_ctrl(mvdev, dd);
 640
 641         mvdev->dd = dd;
 642         mvdev->virtio_id = type;
 643         vqconfig = mic_vq_config(dd);
 644         INIT_WORK(&mvdev->virtio_bh_work, mic_bh_handler);
 645
 646         for (i = 0; i < dd->num_vq; i++) {
 647                 struct mic_vringh *mvr = &mvdev->mvr[i];
 648                 struct mic_vring *vr = &mvdev->mvr[i].vring;
 649                 num = le16_to_cpu(vqconfig[i].num);
 650                 mutex_init(&mvr->vr_mutex);
 651                 vr_size = PAGE_ALIGN(vring_size(num, MIC_VIRTIO_RING_ALIGN) +
 652                         sizeof(struct _mic_vring_info));
 653                 vr->va = (void *)
 654                         __get_free_pages(GFP_KERNEL | __GFP_ZERO,
 655                                          get_order(vr_size));
 656                 if (!vr->va) {
 657                         ret = -ENOMEM;
 658                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 659                                 __func__, __LINE__, ret);
 660                         goto err;
 661                 }
 662                 vr->len = vr_size;
 663                 vr->info = vr->va + vring_size(num, MIC_VIRTIO_RING_ALIGN);
 664                 vr->info->magic = cpu_to_le32(MIC_MAGIC + mvdev->virtio_id + i);
 665                 vr_addr = mic_map_single(mdev, vr->va, vr_size);
 666                 if (mic_map_error(vr_addr)) {
 667                         free_pages((unsigned long)vr->va, get_order(vr_size));
 668                         ret = -ENOMEM;
 669                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 670                                 __func__, __LINE__, ret);
 671                         goto err;
 672                 }
 673                 vqconfig[i].address = cpu_to_le64(vr_addr);
 674
 675                 vring_init(&vr->vr, num, vr->va, MIC_VIRTIO_RING_ALIGN);
 676                 ret = vringh_init_kern(&mvr->vrh,
 677                         *(u32 *)mic_vq_features(mvdev->dd), num, false,
 678                         vr->vr.desc, vr->vr.avail, vr->vr.used);
 679                 if (ret) {
 680                         dev_err(mic_dev(mvdev), "%s %d err %d\n",
 681                                 __func__, __LINE__, ret);
 682                         goto err;
 683                 }
 684                 vringh_kiov_init(&mvr->riov, NULL, 0);
 685                 vringh_kiov_init(&mvr->wiov, NULL, 0);
 686                 mvr->head = USHRT_MAX;
 687                 mvr->mvdev = mvdev;
 688                 mvr->vrh.notify = mic_notify;
 689                 dev_dbg(mdev->sdev->parent,
 690                         "%s %d index %d va %p info %p vr_size 0x%x\n",
 691                         __func__, __LINE__, i, vr->va, vr->info, vr_size);
 692                 mvr->buf = (void *)__get_free_pages(GFP_KERNEL,
 693                                         get_order(MIC_INT_DMA_BUF_SIZE));
 694                 mvr->buf_da = mic_map_single(mvdev->mdev, mvr->buf,
 695                                           MIC_INT_DMA_BUF_SIZE);
 696         }
 697
 698         snprintf(irqname, sizeof(irqname), "mic%dvirtio%d", mdev->id,
 699                  mvdev->virtio_id);
 700         mvdev->virtio_db = mic_next_db(mdev);
 701         mvdev->virtio_cookie = mic_request_threaded_irq(mdev,
 702                                                mic_virtio_intr_handler,
 703                                                NULL, irqname, mvdev,
 704                                                mvdev->virtio_db, MIC_INTR_DB);
 705         if (IS_ERR(mvdev->virtio_cookie)) {
 706                 ret = PTR_ERR(mvdev->virtio_cookie);
 707                 dev_dbg(mdev->sdev->parent, "request irq failed\n");
 708                 goto err;
 709         }
 710
 711         mvdev->dc->c2h_vdev_db = mvdev->virtio_db;
 712
 713         list_add_tail(&mvdev->list, &mdev->vdev_list);
 714         /*
 715          * Order the type update with previous stores. This write barrier
 716          * is paired with the corresponding read barrier before the uncached
 717          * system memory read of the type, on the card while scanning the
 718          * device page.
 719          */
 720         smp_wmb();
 721         dd->type = type;
 722
 723         dev_dbg(mdev->sdev->parent, "Added virtio device id %d\n", dd->type);
 724
 725         db = bootparam->h2c_config_db;
 726         if (db != -1)
 727                 mdev->ops->send_intr(mdev, db);
 728         mutex_unlock(&mdev->mic_mutex);
 729         return 0;
 730 err:
 731         vqconfig = mic_vq_config(dd);
 732         for (j = 0; j < i; j++) {
 733                 struct mic_vringh *mvr = &mvdev->mvr[j];
 734                 mic_unmap_single(mdev, le64_to_cpu(vqconfig[j].address),
 735                                  mvr->vring.len);
 736                 free_pages((unsigned long)mvr->vring.va,
 737                            get_order(mvr->vring.len));
 738         }
 739         mutex_unlock(&mdev->mic_mutex);
 740         return ret;
 741 }
 742
 743 void mic_virtio_del_device(struct mic_vdev *mvdev)
 744 {
 745         struct list_head *pos, *tmp;
 746         struct mic_vdev *tmp_mvdev;
 747         struct mic_device *mdev = mvdev->mdev;
 748         DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wake);
 749         int i, ret, retry;
 750         struct mic_vqconfig *vqconfig;
 751         struct mic_bootparam *bootparam = mdev->dp;
 752         s8 db;
 753
 754         mutex_lock(&mdev->mic_mutex);
 755         db = bootparam->h2c_config_db;
 756         if (db == -1)
 757                 goto skip_hot_remove;
 758         dev_dbg(mdev->sdev->parent,
 759                 "Requesting hot remove id %d\n", mvdev->virtio_id);
 760         mvdev->dc->config_change = MIC_VIRTIO_PARAM_DEV_REMOVE;
 761         mdev->ops->send_intr(mdev, db);
 762         for (retry = 100; retry--;) {
 763                 ret = wait_event_timeout(wake,
 764                         mvdev->dc->guest_ack, msecs_to_jiffies(100));
 765                 if (ret)
 766                         break;
 767         }
 768         dev_dbg(mdev->sdev->parent,
 769                 "Device id %d config_change %d guest_ack %d retry %d\n",
 770                 mvdev->virtio_id, mvdev->dc->config_change,
 771                 mvdev->dc->guest_ack, retry);
 772         mvdev->dc->config_change = 0;
 773         mvdev->dc->guest_ack = 0;
 774 skip_hot_remove:
 775         mic_free_irq(mdev, mvdev->virtio_cookie, mvdev);
 776         flush_work(&mvdev->virtio_bh_work);
 777         vqconfig = mic_vq_config(mvdev->dd);
 778         for (i = 0; i < mvdev->dd->num_vq; i++) {
 779                 struct mic_vringh *mvr = &mvdev->mvr[i];
 780
 781                 mic_unmap_single(mvdev->mdev, mvr->buf_da,
 782                                  MIC_INT_DMA_BUF_SIZE);
 783                 free_pages((unsigned long)mvr->buf,
 784                            get_order(MIC_INT_DMA_BUF_SIZE));
 785                 vringh_kiov_cleanup(&mvr->riov);
 786                 vringh_kiov_cleanup(&mvr->wiov);
 787                 mic_unmap_single(mdev, le64_to_cpu(vqconfig[i].address),
 788                                  mvr->vring.len);
 789                 free_pages((unsigned long)mvr->vring.va,
 790                            get_order(mvr->vring.len));
 791         }
 792
 793         list_for_each_safe(pos, tmp, &mdev->vdev_list) {
 794                 tmp_mvdev = list_entry(pos, struct mic_vdev, list);
 795                 if (tmp_mvdev == mvdev) {
 796                         list_del(pos);
 797                         dev_dbg(mdev->sdev->parent,
 798                                 "Removing virtio device id %d\n",
 799                                 mvdev->virtio_id);
 800                         break;
 801                 }
 802         }
 803         /*
 804          * Order the type update with previous stores. This write barrier
 805          * is paired with the corresponding read barrier before the uncached
 806          * system memory read of the type, on the card while scanning the
 807          * device page.
 808          */
 809         smp_wmb();
 810         mvdev->dd->type = -1;
 811         mutex_unlock(&mdev->mic_mutex);
 812 }