drivers/s390/kvm/virtio_ccw.c

   1 /*
   2  * ccw based virtio transport
   3  *
   4  * Copyright IBM Corp. 2012, 2014
   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 only)
   8  * as published by the Free Software Foundation.
   9  *
  10  *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
  11  */
  12
  13 #include <linux/kernel_stat.h>
  14 #include <linux/init.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/err.h>
  17 #include <linux/virtio.h>
  18 #include <linux/virtio_config.h>
  19 #include <linux/slab.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/virtio_ring.h>
  22 #include <linux/pfn.h>
  23 #include <linux/async.h>
  24 #include <linux/wait.h>
  25 #include <linux/list.h>
  26 #include <linux/bitops.h>
  27 #include <linux/module.h>
  28 #include <linux/io.h>
  29 #include <linux/kvm_para.h>
  30 #include <asm/setup.h>
  31 #include <asm/irq.h>
  32 #include <asm/cio.h>
  33 #include <asm/ccwdev.h>
  34 #include <asm/virtio-ccw.h>
  35 #include <asm/isc.h>
  36 #include <asm/airq.h>
  37
  38 /*
  39  * virtio related functions
  40  */
  41
  42 struct vq_config_block {
  43         __u16 index;
  44         __u16 num;
  45 } __packed;
  46
  47 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  48 /* same as PCI config space size, should be enough for all drivers */
  49
  50 struct virtio_ccw_device {
  51         struct virtio_device vdev;
  52         __u8 *status;
  53         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  54         struct ccw_device *cdev;
  55         __u32 curr_io;
  56         int err;
  57         wait_queue_head_t wait_q;
  58         spinlock_t lock;
  59         struct list_head virtqueues;
  60         unsigned long indicators;
  61         unsigned long indicators2;
  62         struct vq_config_block *config_block;
  63         bool is_thinint;
  64         bool going_away;
  65         void *airq_info;
  66 };
  67
  68 struct vq_info_block {
  69         __u64 queue;
  70         __u32 align;
  71         __u16 index;
  72         __u16 num;
  73 } __packed;
  74
  75 struct virtio_feature_desc {
  76         __u32 features;
  77         __u8 index;
  78 } __packed;
  79
  80 struct virtio_thinint_area {
  81         unsigned long summary_indicator;
  82         unsigned long indicator;
  83         u64 bit_nr;
  84         u8 isc;
  85 } __packed;
  86
  87 struct virtio_ccw_vq_info {
  88         struct virtqueue *vq;
  89         int num;
  90         void *queue;
  91         struct vq_info_block *info_block;
  92         int bit_nr;
  93         struct list_head node;
  94         long cookie;
  95 };
  96
  97 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
  98
  99 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 100 #define MAX_AIRQ_AREAS 20
 101
 102 static int virtio_ccw_use_airq = 1;
 103
 104 struct airq_info {
 105         rwlock_t lock;
 106         u8 summary_indicator;
 107         struct airq_struct airq;
 108         struct airq_iv *aiv;
 109 };
 110 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 111
 112 #define CCW_CMD_SET_VQ 0x13
 113 #define CCW_CMD_VDEV_RESET 0x33
 114 #define CCW_CMD_SET_IND 0x43
 115 #define CCW_CMD_SET_CONF_IND 0x53
 116 #define CCW_CMD_READ_FEAT 0x12
 117 #define CCW_CMD_WRITE_FEAT 0x11
 118 #define CCW_CMD_READ_CONF 0x22
 119 #define CCW_CMD_WRITE_CONF 0x21
 120 #define CCW_CMD_WRITE_STATUS 0x31
 121 #define CCW_CMD_READ_VQ_CONF 0x32
 122 #define CCW_CMD_SET_IND_ADAPTER 0x73
 123
 124 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 125 #define VIRTIO_CCW_DOING_RESET 0x00040000
 126 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 127 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 128 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 129 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 130 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 131 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 132 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 133 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 134 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 135 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 136
 137 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 138 {
 139         return container_of(vdev, struct virtio_ccw_device, vdev);
 140 }
 141
 142 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 143 {
 144         unsigned long i, flags;
 145
 146         write_lock_irqsave(&info->lock, flags);
 147         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 148                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 149                         airq_iv_free_bit(info->aiv, i);
 150                         airq_iv_set_ptr(info->aiv, i, 0);
 151                         break;
 152                 }
 153         }
 154         write_unlock_irqrestore(&info->lock, flags);
 155 }
 156
 157 static void virtio_airq_handler(struct airq_struct *airq)
 158 {
 159         struct airq_info *info = container_of(airq, struct airq_info, airq);
 160         unsigned long ai;
 161
 162         inc_irq_stat(IRQIO_VAI);
 163         read_lock(&info->lock);
 164         /* Walk through indicators field, summary indicator active. */
 165         for (ai = 0;;) {
 166                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 167                 if (ai == -1UL)
 168                         break;
 169                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 170         }
 171         info->summary_indicator = 0;
 172         smp_wmb();
 173         /* Walk through indicators field, summary indicator not active. */
 174         for (ai = 0;;) {
 175                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 176                 if (ai == -1UL)
 177                         break;
 178                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 179         }
 180         read_unlock(&info->lock);
 181 }
 182
 183 static struct airq_info *new_airq_info(void)
 184 {
 185         struct airq_info *info;
 186         int rc;
 187
 188         info = kzalloc(sizeof(*info), GFP_KERNEL);
 189         if (!info)
 190                 return NULL;
 191         rwlock_init(&info->lock);
 192         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
 193         if (!info->aiv) {
 194                 kfree(info);
 195                 return NULL;
 196         }
 197         info->airq.handler = virtio_airq_handler;
 198         info->airq.lsi_ptr = &info->summary_indicator;
 199         info->airq.lsi_mask = 0xff;
 200         info->airq.isc = VIRTIO_AIRQ_ISC;
 201         rc = register_adapter_interrupt(&info->airq);
 202         if (rc) {
 203                 airq_iv_release(info->aiv);
 204                 kfree(info);
 205                 return NULL;
 206         }
 207         return info;
 208 }
 209
 210 static void destroy_airq_info(struct airq_info *info)
 211 {
 212         if (!info)
 213                 return;
 214
 215         unregister_adapter_interrupt(&info->airq);
 216         airq_iv_release(info->aiv);
 217         kfree(info);
 218 }
 219
 220 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 221                                         u64 *first, void **airq_info)
 222 {
 223         int i, j;
 224         struct airq_info *info;
 225         unsigned long indicator_addr = 0;
 226         unsigned long bit, flags;
 227
 228         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 229                 if (!airq_areas[i])
 230                         airq_areas[i] = new_airq_info();
 231                 info = airq_areas[i];
 232                 if (!info)
 233                         return 0;
 234                 write_lock_irqsave(&info->lock, flags);
 235                 bit = airq_iv_alloc(info->aiv, nvqs);
 236                 if (bit == -1UL) {
 237                         /* Not enough vacancies. */
 238                         write_unlock_irqrestore(&info->lock, flags);
 239                         continue;
 240                 }
 241                 *first = bit;
 242                 *airq_info = info;
 243                 indicator_addr = (unsigned long)info->aiv->vector;
 244                 for (j = 0; j < nvqs; j++) {
 245                         airq_iv_set_ptr(info->aiv, bit + j,
 246                                         (unsigned long)vqs[j]);
 247                 }
 248                 write_unlock_irqrestore(&info->lock, flags);
 249         }
 250         return indicator_addr;
 251 }
 252
 253 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 254 {
 255         struct virtio_ccw_vq_info *info;
 256
 257         list_for_each_entry(info, &vcdev->virtqueues, node)
 258                 drop_airq_indicator(info->vq, vcdev->airq_info);
 259 }
 260
 261 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 262 {
 263         unsigned long flags;
 264         __u32 ret;
 265
 266         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 267         if (vcdev->err)
 268                 ret = 0;
 269         else
 270                 ret = vcdev->curr_io & flag;
 271         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 272         return ret;
 273 }
 274
 275 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 276                          struct ccw1 *ccw, __u32 intparm)
 277 {
 278         int ret;
 279         unsigned long flags;
 280         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 281
 282         do {
 283                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 284                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 285                 if (!ret) {
 286                         if (!vcdev->curr_io)
 287                                 vcdev->err = 0;
 288                         vcdev->curr_io |= flag;
 289                 }
 290                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 291                 cpu_relax();
 292         } while (ret == -EBUSY);
 293         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 294         return ret ? ret : vcdev->err;
 295 }
 296
 297 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 298                                       struct ccw1 *ccw)
 299 {
 300         int ret;
 301         unsigned long *indicatorp = NULL;
 302         struct virtio_thinint_area *thinint_area = NULL;
 303         struct airq_info *airq_info = vcdev->airq_info;
 304
 305         if (vcdev->is_thinint) {
 306                 thinint_area = kzalloc(sizeof(*thinint_area),
 307                                        GFP_DMA | GFP_KERNEL);
 308                 if (!thinint_area)
 309                         return;
 310                 thinint_area->summary_indicator =
 311                         (unsigned long) &airq_info->summary_indicator;
 312                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 313                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 314                 ccw->count = sizeof(*thinint_area);
 315                 ccw->cda = (__u32)(unsigned long) thinint_area;
 316         } else {
 317                 indicatorp = kmalloc(sizeof(&vcdev->indicators),
 318                                      GFP_DMA | GFP_KERNEL);
 319                 if (!indicatorp)
 320                         return;
 321                 *indicatorp = 0;
 322                 ccw->cmd_code = CCW_CMD_SET_IND;
 323                 ccw->count = sizeof(vcdev->indicators);
 324                 ccw->cda = (__u32)(unsigned long) indicatorp;
 325         }
 326         /* Deregister indicators from host. */
 327         vcdev->indicators = 0;
 328         ccw->flags = 0;
 329         ret = ccw_io_helper(vcdev, ccw,
 330                             vcdev->is_thinint ?
 331                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 332                             VIRTIO_CCW_DOING_SET_IND);
 333         if (ret && (ret != -ENODEV))
 334                 dev_info(&vcdev->cdev->dev,
 335                          "Failed to deregister indicators (%d)\n", ret);
 336         else if (vcdev->is_thinint)
 337                 virtio_ccw_drop_indicators(vcdev);
 338         kfree(indicatorp);
 339         kfree(thinint_area);
 340 }
 341
 342 static inline long do_kvm_notify(struct subchannel_id schid,
 343                                  unsigned long queue_index,
 344                                  long cookie)
 345 {
 346         register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 347         register struct subchannel_id __schid asm("2") = schid;
 348         register unsigned long __index asm("3") = queue_index;
 349         register long __rc asm("2");
 350         register long __cookie asm("4") = cookie;
 351
 352         asm volatile ("diag 2,4,0x500\n"
 353                       : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 354                       "d"(__cookie)
 355                       : "memory", "cc");
 356         return __rc;
 357 }
 358
 359 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 360 {
 361         struct virtio_ccw_vq_info *info = vq->priv;
 362         struct virtio_ccw_device *vcdev;
 363         struct subchannel_id schid;
 364
 365         vcdev = to_vc_device(info->vq->vdev);
 366         ccw_device_get_schid(vcdev->cdev, &schid);
 367         info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 368         if (info->cookie < 0)
 369                 return false;
 370         return true;
 371 }
 372
 373 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 374                                    struct ccw1 *ccw, int index)
 375 {
 376         vcdev->config_block->index = index;
 377         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 378         ccw->flags = 0;
 379         ccw->count = sizeof(struct vq_config_block);
 380         ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
 381         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 382         return vcdev->config_block->num;
 383 }
 384
 385 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 386 {
 387         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 388         struct virtio_ccw_vq_info *info = vq->priv;
 389         unsigned long flags;
 390         unsigned long size;
 391         int ret;
 392         unsigned int index = vq->index;
 393
 394         /* Remove from our list. */
 395         spin_lock_irqsave(&vcdev->lock, flags);
 396         list_del(&info->node);
 397         spin_unlock_irqrestore(&vcdev->lock, flags);
 398
 399         /* Release from host. */
 400         info->info_block->queue = 0;
 401         info->info_block->align = 0;
 402         info->info_block->index = index;
 403         info->info_block->num = 0;
 404         ccw->cmd_code = CCW_CMD_SET_VQ;
 405         ccw->flags = 0;
 406         ccw->count = sizeof(*info->info_block);
 407         ccw->cda = (__u32)(unsigned long)(info->info_block);
 408         ret = ccw_io_helper(vcdev, ccw,
 409                             VIRTIO_CCW_DOING_SET_VQ | index);
 410         /*
 411          * -ENODEV isn't considered an error: The device is gone anyway.
 412          * This may happen on device detach.
 413          */
 414         if (ret && (ret != -ENODEV))
 415                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d",
 416                          ret, index);
 417
 418         vring_del_virtqueue(vq);
 419         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 420         free_pages_exact(info->queue, size);
 421         kfree(info->info_block);
 422         kfree(info);
 423 }
 424
 425 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 426 {
 427         struct virtqueue *vq, *n;
 428         struct ccw1 *ccw;
 429         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 430
 431         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 432         if (!ccw)
 433                 return;
 434
 435         virtio_ccw_drop_indicator(vcdev, ccw);
 436
 437         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 438                 virtio_ccw_del_vq(vq, ccw);
 439
 440         kfree(ccw);
 441 }
 442
 443 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 444                                              int i, vq_callback_t *callback,
 445                                              const char *name,
 446                                              struct ccw1 *ccw)
 447 {
 448         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 449         int err;
 450         struct virtqueue *vq = NULL;
 451         struct virtio_ccw_vq_info *info;
 452         unsigned long size = 0; /* silence the compiler */
 453         unsigned long flags;
 454
 455         /* Allocate queue. */
 456         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 457         if (!info) {
 458                 dev_warn(&vcdev->cdev->dev, "no info\n");
 459                 err = -ENOMEM;
 460                 goto out_err;
 461         }
 462         info->info_block = kzalloc(sizeof(*info->info_block),
 463                                    GFP_DMA | GFP_KERNEL);
 464         if (!info->info_block) {
 465                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 466                 err = -ENOMEM;
 467                 goto out_err;
 468         }
 469         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 470         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 471         info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
 472         if (info->queue == NULL) {
 473                 dev_warn(&vcdev->cdev->dev, "no queue\n");
 474                 err = -ENOMEM;
 475                 goto out_err;
 476         }
 477
 478         vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
 479                                  true, info->queue, virtio_ccw_kvm_notify,
 480                                  callback, name);
 481         if (!vq) {
 482                 /* For now, we fail if we can't get the requested size. */
 483                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 484                 err = -ENOMEM;
 485                 goto out_err;
 486         }
 487
 488         /* Register it with the host. */
 489         info->info_block->queue = (__u64)info->queue;
 490         info->info_block->align = KVM_VIRTIO_CCW_RING_ALIGN;
 491         info->info_block->index = i;
 492         info->info_block->num = info->num;
 493         ccw->cmd_code = CCW_CMD_SET_VQ;
 494         ccw->flags = 0;
 495         ccw->count = sizeof(*info->info_block);
 496         ccw->cda = (__u32)(unsigned long)(info->info_block);
 497         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 498         if (err) {
 499                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 500                 goto out_err;
 501         }
 502
 503         info->vq = vq;
 504         vq->priv = info;
 505
 506         /* Save it to our list. */
 507         spin_lock_irqsave(&vcdev->lock, flags);
 508         list_add(&info->node, &vcdev->virtqueues);
 509         spin_unlock_irqrestore(&vcdev->lock, flags);
 510
 511         return vq;
 512
 513 out_err:
 514         if (vq)
 515                 vring_del_virtqueue(vq);
 516         if (info) {
 517                 if (info->queue)
 518                         free_pages_exact(info->queue, size);
 519                 kfree(info->info_block);
 520         }
 521         kfree(info);
 522         return ERR_PTR(err);
 523 }
 524
 525 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 526                                            struct virtqueue *vqs[], int nvqs,
 527                                            struct ccw1 *ccw)
 528 {
 529         int ret;
 530         struct virtio_thinint_area *thinint_area = NULL;
 531         struct airq_info *info;
 532
 533         thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
 534         if (!thinint_area) {
 535                 ret = -ENOMEM;
 536                 goto out;
 537         }
 538         /* Try to get an indicator. */
 539         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 540                                                      &thinint_area->bit_nr,
 541                                                      &vcdev->airq_info);
 542         if (!thinint_area->indicator) {
 543                 ret = -ENOSPC;
 544                 goto out;
 545         }
 546         info = vcdev->airq_info;
 547         thinint_area->summary_indicator =
 548                 (unsigned long) &info->summary_indicator;
 549         thinint_area->isc = VIRTIO_AIRQ_ISC;
 550         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 551         ccw->flags = CCW_FLAG_SLI;
 552         ccw->count = sizeof(*thinint_area);
 553         ccw->cda = (__u32)(unsigned long)thinint_area;
 554         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 555         if (ret) {
 556                 if (ret == -EOPNOTSUPP) {
 557                         /*
 558                          * The host does not support adapter interrupts
 559                          * for virtio-ccw, stop trying.
 560                          */
 561                         virtio_ccw_use_airq = 0;
 562                         pr_info("Adapter interrupts unsupported on host\n");
 563                 } else
 564                         dev_warn(&vcdev->cdev->dev,
 565                                  "enabling adapter interrupts = %d\n", ret);
 566                 virtio_ccw_drop_indicators(vcdev);
 567         }
 568 out:
 569         kfree(thinint_area);
 570         return ret;
 571 }
 572
 573 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 574                                struct virtqueue *vqs[],
 575                                vq_callback_t *callbacks[],
 576                                const char *names[])
 577 {
 578         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 579         unsigned long *indicatorp = NULL;
 580         int ret, i;
 581         struct ccw1 *ccw;
 582
 583         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 584         if (!ccw)
 585                 return -ENOMEM;
 586
 587         for (i = 0; i < nvqs; ++i) {
 588                 vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
 589                                              ccw);
 590                 if (IS_ERR(vqs[i])) {
 591                         ret = PTR_ERR(vqs[i]);
 592                         vqs[i] = NULL;
 593                         goto out;
 594                 }
 595         }
 596         ret = -ENOMEM;
 597         /* We need a data area under 2G to communicate. */
 598         indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
 599         if (!indicatorp)
 600                 goto out;
 601         *indicatorp = (unsigned long) &vcdev->indicators;
 602         if (vcdev->is_thinint) {
 603                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 604                 if (ret)
 605                         /* no error, just fall back to legacy interrupts */
 606                         vcdev->is_thinint = 0;
 607         }
 608         if (!vcdev->is_thinint) {
 609                 /* Register queue indicators with host. */
 610                 vcdev->indicators = 0;
 611                 ccw->cmd_code = CCW_CMD_SET_IND;
 612                 ccw->flags = 0;
 613                 ccw->count = sizeof(vcdev->indicators);
 614                 ccw->cda = (__u32)(unsigned long) indicatorp;
 615                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 616                 if (ret)
 617                         goto out;
 618         }
 619         /* Register indicators2 with host for config changes */
 620         *indicatorp = (unsigned long) &vcdev->indicators2;
 621         vcdev->indicators2 = 0;
 622         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 623         ccw->flags = 0;
 624         ccw->count = sizeof(vcdev->indicators2);
 625         ccw->cda = (__u32)(unsigned long) indicatorp;
 626         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 627         if (ret)
 628                 goto out;
 629
 630         kfree(indicatorp);
 631         kfree(ccw);
 632         return 0;
 633 out:
 634         kfree(indicatorp);
 635         kfree(ccw);
 636         virtio_ccw_del_vqs(vdev);
 637         return ret;
 638 }
 639
 640 static void virtio_ccw_reset(struct virtio_device *vdev)
 641 {
 642         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 643         struct ccw1 *ccw;
 644
 645         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 646         if (!ccw)
 647                 return;
 648
 649         /* Zero status bits. */
 650         *vcdev->status = 0;
 651
 652         /* Send a reset ccw on device. */
 653         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 654         ccw->flags = 0;
 655         ccw->count = 0;
 656         ccw->cda = 0;
 657         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 658         kfree(ccw);
 659 }
 660
 661 static u32 virtio_ccw_get_features(struct virtio_device *vdev)
 662 {
 663         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 664         struct virtio_feature_desc *features;
 665         int ret, rc;
 666         struct ccw1 *ccw;
 667
 668         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 669         if (!ccw)
 670                 return 0;
 671
 672         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 673         if (!features) {
 674                 rc = 0;
 675                 goto out_free;
 676         }
 677         /* Read the feature bits from the host. */
 678         /* TODO: Features > 32 bits */
 679         features->index = 0;
 680         ccw->cmd_code = CCW_CMD_READ_FEAT;
 681         ccw->flags = 0;
 682         ccw->count = sizeof(*features);
 683         ccw->cda = (__u32)(unsigned long)features;
 684         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 685         if (ret) {
 686                 rc = 0;
 687                 goto out_free;
 688         }
 689
 690         rc = le32_to_cpu(features->features);
 691
 692 out_free:
 693         kfree(features);
 694         kfree(ccw);
 695         return rc;
 696 }
 697
 698 static void virtio_ccw_finalize_features(struct virtio_device *vdev)
 699 {
 700         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 701         struct virtio_feature_desc *features;
 702         int i;
 703         struct ccw1 *ccw;
 704
 705         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 706         if (!ccw)
 707                 return;
 708
 709         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 710         if (!features)
 711                 goto out_free;
 712
 713         /* Give virtio_ring a chance to accept features. */
 714         vring_transport_features(vdev);
 715
 716         for (i = 0; i < sizeof(*vdev->features) / sizeof(features->features);
 717              i++) {
 718                 int highbits = i % 2 ? 32 : 0;
 719                 features->index = i;
 720                 features->features = cpu_to_le32(vdev->features[i / 2]
 721                                                  >> highbits);
 722                 /* Write the feature bits to the host. */
 723                 ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 724                 ccw->flags = 0;
 725                 ccw->count = sizeof(*features);
 726                 ccw->cda = (__u32)(unsigned long)features;
 727                 ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 728         }
 729 out_free:
 730         kfree(features);
 731         kfree(ccw);
 732 }
 733
 734 static void virtio_ccw_get_config(struct virtio_device *vdev,
 735                                   unsigned int offset, void *buf, unsigned len)
 736 {
 737         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 738         int ret;
 739         struct ccw1 *ccw;
 740         void *config_area;
 741
 742         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 743         if (!ccw)
 744                 return;
 745
 746         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 747         if (!config_area)
 748                 goto out_free;
 749
 750         /* Read the config area from the host. */
 751         ccw->cmd_code = CCW_CMD_READ_CONF;
 752         ccw->flags = 0;
 753         ccw->count = offset + len;
 754         ccw->cda = (__u32)(unsigned long)config_area;
 755         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 756         if (ret)
 757                 goto out_free;
 758
 759         memcpy(vcdev->config, config_area, sizeof(vcdev->config));
 760         memcpy(buf, &vcdev->config[offset], len);
 761
 762 out_free:
 763         kfree(config_area);
 764         kfree(ccw);
 765 }
 766
 767 static void virtio_ccw_set_config(struct virtio_device *vdev,
 768                                   unsigned int offset, const void *buf,
 769                                   unsigned len)
 770 {
 771         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 772         struct ccw1 *ccw;
 773         void *config_area;
 774
 775         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 776         if (!ccw)
 777                 return;
 778
 779         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 780         if (!config_area)
 781                 goto out_free;
 782
 783         memcpy(&vcdev->config[offset], buf, len);
 784         /* Write the config area to the host. */
 785         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 786         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 787         ccw->flags = 0;
 788         ccw->count = offset + len;
 789         ccw->cda = (__u32)(unsigned long)config_area;
 790         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 791
 792 out_free:
 793         kfree(config_area);
 794         kfree(ccw);
 795 }
 796
 797 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 798 {
 799         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 800
 801         return *vcdev->status;
 802 }
 803
 804 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 805 {
 806         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 807         struct ccw1 *ccw;
 808
 809         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 810         if (!ccw)
 811                 return;
 812
 813         /* Write the status to the host. */
 814         *vcdev->status = status;
 815         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 816         ccw->flags = 0;
 817         ccw->count = sizeof(status);
 818         ccw->cda = (__u32)(unsigned long)vcdev->status;
 819         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 820         kfree(ccw);
 821 }
 822
 823 static struct virtio_config_ops virtio_ccw_config_ops = {
 824         .get_features = virtio_ccw_get_features,
 825         .finalize_features = virtio_ccw_finalize_features,
 826         .get = virtio_ccw_get_config,
 827         .set = virtio_ccw_set_config,
 828         .get_status = virtio_ccw_get_status,
 829         .set_status = virtio_ccw_set_status,
 830         .reset = virtio_ccw_reset,
 831         .find_vqs = virtio_ccw_find_vqs,
 832         .del_vqs = virtio_ccw_del_vqs,
 833 };
 834
 835
 836 /*
 837  * ccw bus driver related functions
 838  */
 839
 840 static void virtio_ccw_release_dev(struct device *_d)
 841 {
 842         struct virtio_device *dev = container_of(_d, struct virtio_device,
 843                                                  dev);
 844         struct virtio_ccw_device *vcdev = to_vc_device(dev);
 845
 846         kfree(vcdev->status);
 847         kfree(vcdev->config_block);
 848         kfree(vcdev);
 849 }
 850
 851 static int irb_is_error(struct irb *irb)
 852 {
 853         if (scsw_cstat(&irb->scsw) != 0)
 854                 return 1;
 855         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
 856                 return 1;
 857         if (scsw_cc(&irb->scsw) != 0)
 858                 return 1;
 859         return 0;
 860 }
 861
 862 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
 863                                               int index)
 864 {
 865         struct virtio_ccw_vq_info *info;
 866         unsigned long flags;
 867         struct virtqueue *vq;
 868
 869         vq = NULL;
 870         spin_lock_irqsave(&vcdev->lock, flags);
 871         list_for_each_entry(info, &vcdev->virtqueues, node) {
 872                 if (info->vq->index == index) {
 873                         vq = info->vq;
 874                         break;
 875                 }
 876         }
 877         spin_unlock_irqrestore(&vcdev->lock, flags);
 878         return vq;
 879 }
 880
 881 static void virtio_ccw_int_handler(struct ccw_device *cdev,
 882                                    unsigned long intparm,
 883                                    struct irb *irb)
 884 {
 885         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
 886         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
 887         int i;
 888         struct virtqueue *vq;
 889         struct virtio_driver *drv;
 890
 891         if (!vcdev)
 892                 return;
 893         /* Check if it's a notification from the host. */
 894         if ((intparm == 0) &&
 895             (scsw_stctl(&irb->scsw) ==
 896              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
 897                 /* OK */
 898         }
 899         if (irb_is_error(irb)) {
 900                 /* Command reject? */
 901                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
 902                     (irb->ecw[0] & SNS0_CMD_REJECT))
 903                         vcdev->err = -EOPNOTSUPP;
 904                 else
 905                         /* Map everything else to -EIO. */
 906                         vcdev->err = -EIO;
 907         }
 908         if (vcdev->curr_io & activity) {
 909                 switch (activity) {
 910                 case VIRTIO_CCW_DOING_READ_FEAT:
 911                 case VIRTIO_CCW_DOING_WRITE_FEAT:
 912                 case VIRTIO_CCW_DOING_READ_CONFIG:
 913                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
 914                 case VIRTIO_CCW_DOING_WRITE_STATUS:
 915                 case VIRTIO_CCW_DOING_SET_VQ:
 916                 case VIRTIO_CCW_DOING_SET_IND:
 917                 case VIRTIO_CCW_DOING_SET_CONF_IND:
 918                 case VIRTIO_CCW_DOING_RESET:
 919                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
 920                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
 921                         vcdev->curr_io &= ~activity;
 922                         wake_up(&vcdev->wait_q);
 923                         break;
 924                 default:
 925                         /* don't know what to do... */
 926                         dev_warn(&cdev->dev, "Suspicious activity '%08x'\n",
 927                                  activity);
 928                         WARN_ON(1);
 929                         break;
 930                 }
 931         }
 932         for_each_set_bit(i, &vcdev->indicators,
 933                          sizeof(vcdev->indicators) * BITS_PER_BYTE) {
 934                 /* The bit clear must happen before the vring kick. */
 935                 clear_bit(i, &vcdev->indicators);
 936                 barrier();
 937                 vq = virtio_ccw_vq_by_ind(vcdev, i);
 938                 vring_interrupt(0, vq);
 939         }
 940         if (test_bit(0, &vcdev->indicators2)) {
 941                 drv = container_of(vcdev->vdev.dev.driver,
 942                                    struct virtio_driver, driver);
 943
 944                 if (drv && drv->config_changed)
 945                         drv->config_changed(&vcdev->vdev);
 946                 clear_bit(0, &vcdev->indicators2);
 947         }
 948 }
 949
 950 /*
 951  * We usually want to autoonline all devices, but give the admin
 952  * a way to exempt devices from this.
 953  */
 954 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
 955                      (8*sizeof(long)))
 956 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
 957
 958 static char *no_auto = "";
 959
 960 module_param(no_auto, charp, 0444);
 961 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
 962
 963 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
 964 {
 965         struct ccw_dev_id id;
 966
 967         ccw_device_get_id(cdev, &id);
 968         if (test_bit(id.devno, devs_no_auto[id.ssid]))
 969                 return 0;
 970         return 1;
 971 }
 972
 973 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
 974 {
 975         struct ccw_device *cdev = data;
 976         int ret;
 977
 978         ret = ccw_device_set_online(cdev);
 979         if (ret)
 980                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
 981 }
 982
 983 static int virtio_ccw_probe(struct ccw_device *cdev)
 984 {
 985         cdev->handler = virtio_ccw_int_handler;
 986
 987         if (virtio_ccw_check_autoonline(cdev))
 988                 async_schedule(virtio_ccw_auto_online, cdev);
 989         return 0;
 990 }
 991
 992 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
 993 {
 994         unsigned long flags;
 995         struct virtio_ccw_device *vcdev;
 996
 997         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
 998         vcdev = dev_get_drvdata(&cdev->dev);
 999         if (!vcdev || vcdev->going_away) {
1000                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1001                 return NULL;
1002         }
1003         vcdev->going_away = true;
1004         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1005         return vcdev;
1006 }
1007
1008 static void virtio_ccw_remove(struct ccw_device *cdev)
1009 {
1010         unsigned long flags;
1011         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1012
1013         if (vcdev && cdev->online)
1014                 unregister_virtio_device(&vcdev->vdev);
1015         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1016         dev_set_drvdata(&cdev->dev, NULL);
1017         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1018         cdev->handler = NULL;
1019 }
1020
1021 static int virtio_ccw_offline(struct ccw_device *cdev)
1022 {
1023         unsigned long flags;
1024         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1025
1026         if (vcdev) {
1027                 unregister_virtio_device(&vcdev->vdev);
1028                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1029                 dev_set_drvdata(&cdev->dev, NULL);
1030                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1031         }
1032         return 0;
1033 }
1034
1035
1036 static int virtio_ccw_online(struct ccw_device *cdev)
1037 {
1038         int ret;
1039         struct virtio_ccw_device *vcdev;
1040         unsigned long flags;
1041
1042         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1043         if (!vcdev) {
1044                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1045                 ret = -ENOMEM;
1046                 goto out_free;
1047         }
1048         vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1049                                    GFP_DMA | GFP_KERNEL);
1050         if (!vcdev->config_block) {
1051                 ret = -ENOMEM;
1052                 goto out_free;
1053         }
1054         vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1055         if (!vcdev->status) {
1056                 ret = -ENOMEM;
1057                 goto out_free;
1058         }
1059
1060         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1061
1062         vcdev->vdev.dev.parent = &cdev->dev;
1063         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1064         vcdev->vdev.config = &virtio_ccw_config_ops;
1065         vcdev->cdev = cdev;
1066         init_waitqueue_head(&vcdev->wait_q);
1067         INIT_LIST_HEAD(&vcdev->virtqueues);
1068         spin_lock_init(&vcdev->lock);
1069
1070         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1071         dev_set_drvdata(&cdev->dev, vcdev);
1072         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1073         vcdev->vdev.id.vendor = cdev->id.cu_type;
1074         vcdev->vdev.id.device = cdev->id.cu_model;
1075         ret = register_virtio_device(&vcdev->vdev);
1076         if (ret) {
1077                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1078                          ret);
1079                 goto out_put;
1080         }
1081         return 0;
1082 out_put:
1083         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1084         dev_set_drvdata(&cdev->dev, NULL);
1085         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1086         put_device(&vcdev->vdev.dev);
1087         return ret;
1088 out_free:
1089         if (vcdev) {
1090                 kfree(vcdev->status);
1091                 kfree(vcdev->config_block);
1092         }
1093         kfree(vcdev);
1094         return ret;
1095 }
1096
1097 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1098 {
1099         /* TODO: Check whether we need special handling here. */
1100         return 0;
1101 }
1102
1103 static struct ccw_device_id virtio_ids[] = {
1104         { CCW_DEVICE(0x3832, 0) },
1105         {},
1106 };
1107 MODULE_DEVICE_TABLE(ccw, virtio_ids);
1108
1109 static struct ccw_driver virtio_ccw_driver = {
1110         .driver = {
1111                 .owner = THIS_MODULE,
1112                 .name = "virtio_ccw",
1113         },
1114         .ids = virtio_ids,
1115         .probe = virtio_ccw_probe,
1116         .remove = virtio_ccw_remove,
1117         .set_offline = virtio_ccw_offline,
1118         .set_online = virtio_ccw_online,
1119         .notify = virtio_ccw_cio_notify,
1120         .int_class = IRQIO_VIR,
1121 };
1122
1123 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1124                            int max_digit, int max_val)
1125 {
1126         int diff;
1127
1128         diff = 0;
1129         *val = 0;
1130
1131         while (diff <= max_digit) {
1132                 int value = hex_to_bin(**cp);
1133
1134                 if (value < 0)
1135                         break;
1136                 *val = *val * 16 + value;
1137                 (*cp)++;
1138                 diff++;
1139         }
1140
1141         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1142                 return 1;
1143
1144         return 0;
1145 }
1146
1147 static int __init parse_busid(char *str, unsigned int *cssid,
1148                               unsigned int *ssid, unsigned int *devno)
1149 {
1150         char *str_work;
1151         int rc, ret;
1152
1153         rc = 1;
1154
1155         if (*str == '\0')
1156                 goto out;
1157
1158         str_work = str;
1159         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1160         if (ret || (str_work[0] != '.'))
1161                 goto out;
1162         str_work++;
1163         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1164         if (ret || (str_work[0] != '.'))
1165                 goto out;
1166         str_work++;
1167         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1168         if (ret || (str_work[0] != '\0'))
1169                 goto out;
1170
1171         rc = 0;
1172 out:
1173         return rc;
1174 }
1175
1176 static void __init no_auto_parse(void)
1177 {
1178         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1179         char *parm, *str;
1180         int rc;
1181
1182         str = no_auto;
1183         while ((parm = strsep(&str, ","))) {
1184                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1185                                  &from_ssid, &from);
1186                 if (rc)
1187                         continue;
1188                 if (parm != NULL) {
1189                         rc = parse_busid(parm, &to_cssid,
1190                                          &to_ssid, &to);
1191                         if ((from_ssid > to_ssid) ||
1192                             ((from_ssid == to_ssid) && (from > to)))
1193                                 rc = -EINVAL;
1194                 } else {
1195                         to_cssid = from_cssid;
1196                         to_ssid = from_ssid;
1197                         to = from;
1198                 }
1199                 if (rc)
1200                         continue;
1201                 while ((from_ssid < to_ssid) ||
1202                        ((from_ssid == to_ssid) && (from <= to))) {
1203                         set_bit(from, devs_no_auto[from_ssid]);
1204                         from++;
1205                         if (from > __MAX_SUBCHANNEL) {
1206                                 from_ssid++;
1207                                 from = 0;
1208                         }
1209                 }
1210         }
1211 }
1212
1213 static int __init virtio_ccw_init(void)
1214 {
1215         /* parse no_auto string before we do anything further */
1216         no_auto_parse();
1217         return ccw_driver_register(&virtio_ccw_driver);
1218 }
1219 module_init(virtio_ccw_init);
1220
1221 static void __exit virtio_ccw_exit(void)
1222 {
1223         int i;
1224
1225         ccw_driver_unregister(&virtio_ccw_driver);
1226         for (i = 0; i < MAX_AIRQ_AREAS; i++)
1227                 destroy_airq_info(airq_areas[i]);
1228 }
1229 module_exit(virtio_ccw_exit);