drivers/s390/virtio/virtio_ccw.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ccw based virtio transport
   4  *
   5  * Copyright IBM Corp. 2012, 2014
   6  *
   7  *    Author(s): Cornelia Huck <[email protected]>
   8  */
   9
  10 #include <linux/kernel_stat.h>
  11 #include <linux/init.h>
  12 #include <linux/memblock.h>
  13 #include <linux/err.h>
  14 #include <linux/virtio.h>
  15 #include <linux/virtio_config.h>
  16 #include <linux/slab.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/virtio_ring.h>
  19 #include <linux/pfn.h>
  20 #include <linux/async.h>
  21 #include <linux/wait.h>
  22 #include <linux/list.h>
  23 #include <linux/bitops.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/io.h>
  26 #include <linux/kvm_para.h>
  27 #include <linux/notifier.h>
  28 #include <asm/diag.h>
  29 #include <asm/setup.h>
  30 #include <asm/irq.h>
  31 #include <asm/cio.h>
  32 #include <asm/ccwdev.h>
  33 #include <asm/virtio-ccw.h>
  34 #include <asm/isc.h>
  35 #include <asm/airq.h>
  36 #include <asm/tpi.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 vcdev_dma_area {
  51         unsigned long indicators;
  52         unsigned long indicators2;
  53         struct vq_config_block config_block;
  54         __u8 status;
  55 };
  56
  57 struct virtio_ccw_device {
  58         struct virtio_device vdev;
  59         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  60         struct ccw_device *cdev;
  61         /* we make cdev->dev.dma_parms point to this */
  62         struct device_dma_parameters dma_parms;
  63         __u32 curr_io;
  64         int err;
  65         unsigned int revision; /* Transport revision */
  66         wait_queue_head_t wait_q;
  67         spinlock_t lock;
  68         rwlock_t irq_lock;
  69         struct mutex io_lock; /* Serializes I/O requests */
  70         struct list_head virtqueues;
  71         bool is_thinint;
  72         bool going_away;
  73         bool device_lost;
  74         unsigned int config_ready;
  75         void *airq_info;
  76         struct vcdev_dma_area *dma_area;
  77         dma32_t dma_area_addr;
  78 };
  79
  80 static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  81 {
  82         return &vcdev->dma_area->indicators;
  83 }
  84
  85 static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  86 {
  87         return &vcdev->dma_area->indicators2;
  88 }
  89
  90 /* Spec stipulates a 64 bit address */
  91 static inline dma64_t indicators_dma(struct virtio_ccw_device *vcdev)
  92 {
  93         u64 dma_area_addr = dma32_to_u32(vcdev->dma_area_addr);
  94
  95         return dma64_add(u64_to_dma64(dma_area_addr),
  96                          offsetof(struct vcdev_dma_area, indicators));
  97 }
  98
  99 /* Spec stipulates a 64 bit address */
 100 static inline dma64_t indicators2_dma(struct virtio_ccw_device *vcdev)
 101 {
 102         u64 dma_area_addr = dma32_to_u32(vcdev->dma_area_addr);
 103
 104         return dma64_add(u64_to_dma64(dma_area_addr),
 105                          offsetof(struct vcdev_dma_area, indicators2));
 106 }
 107
 108 static inline dma32_t config_block_dma(struct virtio_ccw_device *vcdev)
 109 {
 110         return dma32_add(vcdev->dma_area_addr,
 111                          offsetof(struct vcdev_dma_area, config_block));
 112 }
 113
 114 static inline dma32_t status_dma(struct virtio_ccw_device *vcdev)
 115 {
 116         return dma32_add(vcdev->dma_area_addr,
 117                          offsetof(struct vcdev_dma_area, status));
 118 }
 119
 120 struct vq_info_block_legacy {
 121         dma64_t queue;
 122         __u32 align;
 123         __u16 index;
 124         __u16 num;
 125 } __packed;
 126
 127 struct vq_info_block {
 128         dma64_t desc;
 129         __u32 res0;
 130         __u16 index;
 131         __u16 num;
 132         dma64_t avail;
 133         dma64_t used;
 134 } __packed;
 135
 136 struct virtio_feature_desc {
 137         __le32 features;
 138         __u8 index;
 139 } __packed;
 140
 141 struct virtio_thinint_area {
 142         dma64_t summary_indicator;
 143         dma64_t indicator;
 144         u64 bit_nr;
 145         u8 isc;
 146 } __packed;
 147
 148 struct virtio_rev_info {
 149         __u16 revision;
 150         __u16 length;
 151         __u8 data[];
 152 };
 153
 154 /* the highest virtio-ccw revision we support */
 155 #define VIRTIO_CCW_REV_MAX 2
 156
 157 struct virtio_ccw_vq_info {
 158         struct virtqueue *vq;
 159         dma32_t info_block_addr;
 160         int num;
 161         union {
 162                 struct vq_info_block s;
 163                 struct vq_info_block_legacy l;
 164         } *info_block;
 165         int bit_nr;
 166         struct list_head node;
 167         long cookie;
 168 };
 169
 170 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 171
 172 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 173 #define MAX_AIRQ_AREAS 20
 174
 175 static int virtio_ccw_use_airq = 1;
 176
 177 struct airq_info {
 178         rwlock_t lock;
 179         u8 summary_indicator_idx;
 180         struct airq_struct airq;
 181         struct airq_iv *aiv;
 182 };
 183 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 184 static DEFINE_MUTEX(airq_areas_lock);
 185
 186 static u8 *summary_indicators;
 187
 188 static inline u8 *get_summary_indicator(struct airq_info *info)
 189 {
 190         return summary_indicators + info->summary_indicator_idx;
 191 }
 192
 193 static inline dma64_t get_summary_indicator_dma(struct airq_info *info)
 194 {
 195         return virt_to_dma64(get_summary_indicator(info));
 196 }
 197
 198 #define CCW_CMD_SET_VQ 0x13
 199 #define CCW_CMD_VDEV_RESET 0x33
 200 #define CCW_CMD_SET_IND 0x43
 201 #define CCW_CMD_SET_CONF_IND 0x53
 202 #define CCW_CMD_READ_FEAT 0x12
 203 #define CCW_CMD_WRITE_FEAT 0x11
 204 #define CCW_CMD_READ_CONF 0x22
 205 #define CCW_CMD_WRITE_CONF 0x21
 206 #define CCW_CMD_WRITE_STATUS 0x31
 207 #define CCW_CMD_READ_VQ_CONF 0x32
 208 #define CCW_CMD_READ_STATUS 0x72
 209 #define CCW_CMD_SET_IND_ADAPTER 0x73
 210 #define CCW_CMD_SET_VIRTIO_REV 0x83
 211
 212 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 213 #define VIRTIO_CCW_DOING_RESET 0x00040000
 214 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 215 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 216 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 217 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 218 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 219 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 220 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 221 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 222 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 223 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 224 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 225 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 226
 227 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 228 {
 229         return container_of(vdev, struct virtio_ccw_device, vdev);
 230 }
 231
 232 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 233 {
 234         unsigned long i, flags;
 235
 236         write_lock_irqsave(&info->lock, flags);
 237         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 238                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 239                         airq_iv_free_bit(info->aiv, i);
 240                         airq_iv_set_ptr(info->aiv, i, 0);
 241                         break;
 242                 }
 243         }
 244         write_unlock_irqrestore(&info->lock, flags);
 245 }
 246
 247 static void virtio_airq_handler(struct airq_struct *airq,
 248                                 struct tpi_info *tpi_info)
 249 {
 250         struct airq_info *info = container_of(airq, struct airq_info, airq);
 251         unsigned long ai;
 252
 253         inc_irq_stat(IRQIO_VAI);
 254         read_lock(&info->lock);
 255         /* Walk through indicators field, summary indicator active. */
 256         for (ai = 0;;) {
 257                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 258                 if (ai == -1UL)
 259                         break;
 260                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 261         }
 262         *(get_summary_indicator(info)) = 0;
 263         smp_wmb();
 264         /* Walk through indicators field, summary indicator not active. */
 265         for (ai = 0;;) {
 266                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 267                 if (ai == -1UL)
 268                         break;
 269                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 270         }
 271         read_unlock(&info->lock);
 272 }
 273
 274 static struct airq_info *new_airq_info(int index)
 275 {
 276         struct airq_info *info;
 277         int rc;
 278
 279         info = kzalloc(sizeof(*info), GFP_KERNEL);
 280         if (!info)
 281                 return NULL;
 282         rwlock_init(&info->lock);
 283         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 284                                    | AIRQ_IV_CACHELINE, NULL);
 285         if (!info->aiv) {
 286                 kfree(info);
 287                 return NULL;
 288         }
 289         info->airq.handler = virtio_airq_handler;
 290         info->summary_indicator_idx = index;
 291         info->airq.lsi_ptr = get_summary_indicator(info);
 292         info->airq.isc = VIRTIO_AIRQ_ISC;
 293         rc = register_adapter_interrupt(&info->airq);
 294         if (rc) {
 295                 airq_iv_release(info->aiv);
 296                 kfree(info);
 297                 return NULL;
 298         }
 299         return info;
 300 }
 301
 302 static unsigned long *get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 303                                          u64 *first, void **airq_info)
 304 {
 305         int i, j;
 306         struct airq_info *info;
 307         unsigned long *indicator_addr = NULL;
 308         unsigned long bit, flags;
 309
 310         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 311                 mutex_lock(&airq_areas_lock);
 312                 if (!airq_areas[i])
 313                         airq_areas[i] = new_airq_info(i);
 314                 info = airq_areas[i];
 315                 mutex_unlock(&airq_areas_lock);
 316                 if (!info)
 317                         return NULL;
 318                 write_lock_irqsave(&info->lock, flags);
 319                 bit = airq_iv_alloc(info->aiv, nvqs);
 320                 if (bit == -1UL) {
 321                         /* Not enough vacancies. */
 322                         write_unlock_irqrestore(&info->lock, flags);
 323                         continue;
 324                 }
 325                 *first = bit;
 326                 *airq_info = info;
 327                 indicator_addr = info->aiv->vector;
 328                 for (j = 0; j < nvqs; j++) {
 329                         airq_iv_set_ptr(info->aiv, bit + j,
 330                                         (unsigned long)vqs[j]);
 331                 }
 332                 write_unlock_irqrestore(&info->lock, flags);
 333         }
 334         return indicator_addr;
 335 }
 336
 337 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 338 {
 339         struct virtio_ccw_vq_info *info;
 340
 341         if (!vcdev->airq_info)
 342                 return;
 343         list_for_each_entry(info, &vcdev->virtqueues, node)
 344                 drop_airq_indicator(info->vq, vcdev->airq_info);
 345 }
 346
 347 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 348 {
 349         unsigned long flags;
 350         __u32 ret;
 351
 352         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 353         if (vcdev->err)
 354                 ret = 0;
 355         else
 356                 ret = vcdev->curr_io & flag;
 357         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 358         return ret;
 359 }
 360
 361 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 362                          struct ccw1 *ccw, __u32 intparm)
 363 {
 364         int ret;
 365         unsigned long flags;
 366         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 367
 368         mutex_lock(&vcdev->io_lock);
 369         do {
 370                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 371                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 372                 if (!ret) {
 373                         if (!vcdev->curr_io)
 374                                 vcdev->err = 0;
 375                         vcdev->curr_io |= flag;
 376                 }
 377                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 378                 cpu_relax();
 379         } while (ret == -EBUSY);
 380         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 381         ret = ret ? ret : vcdev->err;
 382         mutex_unlock(&vcdev->io_lock);
 383         return ret;
 384 }
 385
 386 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 387                                       struct ccw1 *ccw)
 388 {
 389         int ret;
 390         struct virtio_thinint_area *thinint_area = NULL;
 391         struct airq_info *airq_info = vcdev->airq_info;
 392         dma64_t *indicatorp = NULL;
 393
 394         if (vcdev->is_thinint) {
 395                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 396                                                      sizeof(*thinint_area),
 397                                                      &ccw->cda);
 398                 if (!thinint_area)
 399                         return;
 400                 thinint_area->summary_indicator =
 401                         get_summary_indicator_dma(airq_info);
 402                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 403                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 404                 ccw->count = sizeof(*thinint_area);
 405         } else {
 406                 /* payload is the address of the indicators */
 407                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 408                                                    sizeof(*indicatorp),
 409                                                    &ccw->cda);
 410                 if (!indicatorp)
 411                         return;
 412                 *indicatorp = 0;
 413                 ccw->cmd_code = CCW_CMD_SET_IND;
 414                 ccw->count = sizeof(*indicatorp);
 415         }
 416         /* Deregister indicators from host. */
 417         *indicators(vcdev) = 0;
 418         ccw->flags = 0;
 419         ret = ccw_io_helper(vcdev, ccw,
 420                             vcdev->is_thinint ?
 421                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 422                             VIRTIO_CCW_DOING_SET_IND);
 423         if (ret && (ret != -ENODEV))
 424                 dev_info(&vcdev->cdev->dev,
 425                          "Failed to deregister indicators (%d)\n", ret);
 426         else if (vcdev->is_thinint)
 427                 virtio_ccw_drop_indicators(vcdev);
 428         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(*indicatorp));
 429         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 430 }
 431
 432 static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data)
 433 {
 434         struct virtio_ccw_vq_info *info = vq->priv;
 435         struct virtio_ccw_device *vcdev;
 436         struct subchannel_id schid;
 437
 438         vcdev = to_vc_device(info->vq->vdev);
 439         ccw_device_get_schid(vcdev->cdev, &schid);
 440         BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
 441         info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
 442                                       *((unsigned int *)&schid),
 443                                       data, info->cookie);
 444         if (info->cookie < 0)
 445                 return false;
 446         return true;
 447 }
 448
 449 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 450 {
 451         return virtio_ccw_do_kvm_notify(vq, vq->index);
 452 }
 453
 454 static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq)
 455 {
 456         return virtio_ccw_do_kvm_notify(vq, vring_notification_data(vq));
 457 }
 458
 459 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 460                                    struct ccw1 *ccw, int index)
 461 {
 462         int ret;
 463
 464         vcdev->dma_area->config_block.index = index;
 465         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 466         ccw->flags = 0;
 467         ccw->count = sizeof(struct vq_config_block);
 468         ccw->cda = config_block_dma(vcdev);
 469         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 470         if (ret)
 471                 return ret;
 472         return vcdev->dma_area->config_block.num ?: -ENOENT;
 473 }
 474
 475 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 476 {
 477         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 478         struct virtio_ccw_vq_info *info = vq->priv;
 479         unsigned long flags;
 480         int ret;
 481         unsigned int index = vq->index;
 482
 483         /* Remove from our list. */
 484         spin_lock_irqsave(&vcdev->lock, flags);
 485         list_del(&info->node);
 486         spin_unlock_irqrestore(&vcdev->lock, flags);
 487
 488         /* Release from host. */
 489         if (vcdev->revision == 0) {
 490                 info->info_block->l.queue = 0;
 491                 info->info_block->l.align = 0;
 492                 info->info_block->l.index = index;
 493                 info->info_block->l.num = 0;
 494                 ccw->count = sizeof(info->info_block->l);
 495         } else {
 496                 info->info_block->s.desc = 0;
 497                 info->info_block->s.index = index;
 498                 info->info_block->s.num = 0;
 499                 info->info_block->s.avail = 0;
 500                 info->info_block->s.used = 0;
 501                 ccw->count = sizeof(info->info_block->s);
 502         }
 503         ccw->cmd_code = CCW_CMD_SET_VQ;
 504         ccw->flags = 0;
 505         ccw->cda = info->info_block_addr;
 506         ret = ccw_io_helper(vcdev, ccw,
 507                             VIRTIO_CCW_DOING_SET_VQ | index);
 508         /*
 509          * -ENODEV isn't considered an error: The device is gone anyway.
 510          * This may happen on device detach.
 511          */
 512         if (ret && (ret != -ENODEV))
 513                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 514                          ret, index);
 515
 516         vring_del_virtqueue(vq);
 517         ccw_device_dma_free(vcdev->cdev, info->info_block,
 518                             sizeof(*info->info_block));
 519         kfree(info);
 520 }
 521
 522 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 523 {
 524         struct virtqueue *vq, *n;
 525         struct ccw1 *ccw;
 526         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 527
 528         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 529         if (!ccw)
 530                 return;
 531
 532         virtio_ccw_drop_indicator(vcdev, ccw);
 533
 534         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 535                 virtio_ccw_del_vq(vq, ccw);
 536
 537         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 538 }
 539
 540 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 541                                              int i, vq_callback_t *callback,
 542                                              const char *name, bool ctx,
 543                                              struct ccw1 *ccw)
 544 {
 545         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 546         bool (*notify)(struct virtqueue *vq);
 547         int err;
 548         struct virtqueue *vq = NULL;
 549         struct virtio_ccw_vq_info *info;
 550         u64 queue;
 551         unsigned long flags;
 552         bool may_reduce;
 553
 554         if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
 555                 notify = virtio_ccw_kvm_notify_with_data;
 556         else
 557                 notify = virtio_ccw_kvm_notify;
 558
 559         /* Allocate queue. */
 560         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 561         if (!info) {
 562                 dev_warn(&vcdev->cdev->dev, "no info\n");
 563                 err = -ENOMEM;
 564                 goto out_err;
 565         }
 566         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 567                                                  sizeof(*info->info_block),
 568                                                  &info->info_block_addr);
 569         if (!info->info_block) {
 570                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 571                 err = -ENOMEM;
 572                 goto out_err;
 573         }
 574         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 575         if (info->num < 0) {
 576                 err = info->num;
 577                 goto out_err;
 578         }
 579         may_reduce = vcdev->revision > 0;
 580         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 581                                     vdev, true, may_reduce, ctx,
 582                                     notify, callback, name);
 583
 584         if (!vq) {
 585                 /* For now, we fail if we can't get the requested size. */
 586                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 587                 err = -ENOMEM;
 588                 goto out_err;
 589         }
 590
 591         vq->num_max = info->num;
 592
 593         /* it may have been reduced */
 594         info->num = virtqueue_get_vring_size(vq);
 595
 596         /* Register it with the host. */
 597         queue = virtqueue_get_desc_addr(vq);
 598         if (vcdev->revision == 0) {
 599                 info->info_block->l.queue = u64_to_dma64(queue);
 600                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 601                 info->info_block->l.index = i;
 602                 info->info_block->l.num = info->num;
 603                 ccw->count = sizeof(info->info_block->l);
 604         } else {
 605                 info->info_block->s.desc = u64_to_dma64(queue);
 606                 info->info_block->s.index = i;
 607                 info->info_block->s.num = info->num;
 608                 info->info_block->s.avail = u64_to_dma64(virtqueue_get_avail_addr(vq));
 609                 info->info_block->s.used = u64_to_dma64(virtqueue_get_used_addr(vq));
 610                 ccw->count = sizeof(info->info_block->s);
 611         }
 612         ccw->cmd_code = CCW_CMD_SET_VQ;
 613         ccw->flags = 0;
 614         ccw->cda = info->info_block_addr;
 615         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 616         if (err) {
 617                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 618                 goto out_err;
 619         }
 620
 621         info->vq = vq;
 622         vq->priv = info;
 623
 624         /* Save it to our list. */
 625         spin_lock_irqsave(&vcdev->lock, flags);
 626         list_add(&info->node, &vcdev->virtqueues);
 627         spin_unlock_irqrestore(&vcdev->lock, flags);
 628
 629         return vq;
 630
 631 out_err:
 632         if (vq)
 633                 vring_del_virtqueue(vq);
 634         if (info) {
 635                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 636                                     sizeof(*info->info_block));
 637         }
 638         kfree(info);
 639         return ERR_PTR(err);
 640 }
 641
 642 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 643                                            struct virtqueue *vqs[], int nvqs,
 644                                            struct ccw1 *ccw)
 645 {
 646         int ret;
 647         struct virtio_thinint_area *thinint_area = NULL;
 648         unsigned long *indicator_addr;
 649         struct airq_info *info;
 650
 651         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 652                                              sizeof(*thinint_area),
 653                                              &ccw->cda);
 654         if (!thinint_area) {
 655                 ret = -ENOMEM;
 656                 goto out;
 657         }
 658         /* Try to get an indicator. */
 659         indicator_addr = get_airq_indicator(vqs, nvqs,
 660                                             &thinint_area->bit_nr,
 661                                             &vcdev->airq_info);
 662         if (!indicator_addr) {
 663                 ret = -ENOSPC;
 664                 goto out;
 665         }
 666         thinint_area->indicator = virt_to_dma64(indicator_addr);
 667         info = vcdev->airq_info;
 668         thinint_area->summary_indicator = get_summary_indicator_dma(info);
 669         thinint_area->isc = VIRTIO_AIRQ_ISC;
 670         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 671         ccw->flags = CCW_FLAG_SLI;
 672         ccw->count = sizeof(*thinint_area);
 673         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 674         if (ret) {
 675                 if (ret == -EOPNOTSUPP) {
 676                         /*
 677                          * The host does not support adapter interrupts
 678                          * for virtio-ccw, stop trying.
 679                          */
 680                         virtio_ccw_use_airq = 0;
 681                         pr_info("Adapter interrupts unsupported on host\n");
 682                 } else
 683                         dev_warn(&vcdev->cdev->dev,
 684                                  "enabling adapter interrupts = %d\n", ret);
 685                 virtio_ccw_drop_indicators(vcdev);
 686         }
 687 out:
 688         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 689         return ret;
 690 }
 691
 692 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 693                                struct virtqueue *vqs[],
 694                                struct virtqueue_info vqs_info[],
 695                                struct irq_affinity *desc)
 696 {
 697         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 698         dma64_t *indicatorp = NULL;
 699         int ret, i, queue_idx = 0;
 700         struct ccw1 *ccw;
 701         dma32_t indicatorp_dma = 0;
 702
 703         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 704         if (!ccw)
 705                 return -ENOMEM;
 706
 707         for (i = 0; i < nvqs; ++i) {
 708                 struct virtqueue_info *vqi = &vqs_info[i];
 709
 710                 if (!vqi->name) {
 711                         vqs[i] = NULL;
 712                         continue;
 713                 }
 714
 715                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, vqi->callback,
 716                                              vqi->name, vqi->ctx, ccw);
 717                 if (IS_ERR(vqs[i])) {
 718                         ret = PTR_ERR(vqs[i]);
 719                         vqs[i] = NULL;
 720                         goto out;
 721                 }
 722         }
 723         ret = -ENOMEM;
 724         /*
 725          * We need a data area under 2G to communicate. Our payload is
 726          * the address of the indicators.
 727         */
 728         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 729                                            sizeof(*indicatorp),
 730                                            &indicatorp_dma);
 731         if (!indicatorp)
 732                 goto out;
 733         *indicatorp = indicators_dma(vcdev);
 734         if (vcdev->is_thinint) {
 735                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 736                 if (ret)
 737                         /* no error, just fall back to legacy interrupts */
 738                         vcdev->is_thinint = false;
 739         }
 740         ccw->cda = indicatorp_dma;
 741         if (!vcdev->is_thinint) {
 742                 /* Register queue indicators with host. */
 743                 *indicators(vcdev) = 0;
 744                 ccw->cmd_code = CCW_CMD_SET_IND;
 745                 ccw->flags = 0;
 746                 ccw->count = sizeof(*indicatorp);
 747                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 748                 if (ret)
 749                         goto out;
 750         }
 751         /* Register indicators2 with host for config changes */
 752         *indicatorp = indicators2_dma(vcdev);
 753         *indicators2(vcdev) = 0;
 754         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 755         ccw->flags = 0;
 756         ccw->count = sizeof(*indicatorp);
 757         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 758         if (ret)
 759                 goto out;
 760
 761         if (indicatorp)
 762                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 763                                     sizeof(*indicatorp));
 764         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 765         return 0;
 766 out:
 767         if (indicatorp)
 768                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 769                                     sizeof(*indicatorp));
 770         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 771         virtio_ccw_del_vqs(vdev);
 772         return ret;
 773 }
 774
 775 static void virtio_ccw_reset(struct virtio_device *vdev)
 776 {
 777         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 778         struct ccw1 *ccw;
 779
 780         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 781         if (!ccw)
 782                 return;
 783
 784         /* Zero status bits. */
 785         vcdev->dma_area->status = 0;
 786
 787         /* Send a reset ccw on device. */
 788         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 789         ccw->flags = 0;
 790         ccw->count = 0;
 791         ccw->cda = 0;
 792         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 793         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 794 }
 795
 796 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 797 {
 798         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 799         struct virtio_feature_desc *features;
 800         int ret;
 801         u64 rc;
 802         struct ccw1 *ccw;
 803
 804         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 805         if (!ccw)
 806                 return 0;
 807
 808         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
 809                                          &ccw->cda);
 810         if (!features) {
 811                 rc = 0;
 812                 goto out_free;
 813         }
 814         /* Read the feature bits from the host. */
 815         features->index = 0;
 816         ccw->cmd_code = CCW_CMD_READ_FEAT;
 817         ccw->flags = 0;
 818         ccw->count = sizeof(*features);
 819         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 820         if (ret) {
 821                 rc = 0;
 822                 goto out_free;
 823         }
 824
 825         rc = le32_to_cpu(features->features);
 826
 827         if (vcdev->revision == 0)
 828                 goto out_free;
 829
 830         /* Read second half of the feature bits from the host. */
 831         features->index = 1;
 832         ccw->cmd_code = CCW_CMD_READ_FEAT;
 833         ccw->flags = 0;
 834         ccw->count = sizeof(*features);
 835         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 836         if (ret == 0)
 837                 rc |= (u64)le32_to_cpu(features->features) << 32;
 838
 839 out_free:
 840         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 841         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 842         return rc;
 843 }
 844
 845 static void ccw_transport_features(struct virtio_device *vdev)
 846 {
 847         /*
 848          * Currently nothing to do here.
 849          */
 850 }
 851
 852 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 853 {
 854         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 855         struct virtio_feature_desc *features;
 856         struct ccw1 *ccw;
 857         int ret;
 858
 859         if (vcdev->revision >= 1 &&
 860             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 861                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 862                         "but does not have VIRTIO_F_VERSION_1\n");
 863                 return -EINVAL;
 864         }
 865
 866         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 867         if (!ccw)
 868                 return -ENOMEM;
 869
 870         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
 871                                          &ccw->cda);
 872         if (!features) {
 873                 ret = -ENOMEM;
 874                 goto out_free;
 875         }
 876         /* Give virtio_ring a chance to accept features. */
 877         vring_transport_features(vdev);
 878
 879         /* Give virtio_ccw a chance to accept features. */
 880         ccw_transport_features(vdev);
 881
 882         features->index = 0;
 883         features->features = cpu_to_le32((u32)vdev->features);
 884         /* Write the first half of the feature bits to the host. */
 885         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 886         ccw->flags = 0;
 887         ccw->count = sizeof(*features);
 888         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 889         if (ret)
 890                 goto out_free;
 891
 892         if (vcdev->revision == 0)
 893                 goto out_free;
 894
 895         features->index = 1;
 896         features->features = cpu_to_le32(vdev->features >> 32);
 897         /* Write the second half of the feature bits to the host. */
 898         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 899         ccw->flags = 0;
 900         ccw->count = sizeof(*features);
 901         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 902
 903 out_free:
 904         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 905         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 906
 907         return ret;
 908 }
 909
 910 static void virtio_ccw_get_config(struct virtio_device *vdev,
 911                                   unsigned int offset, void *buf, unsigned len)
 912 {
 913         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 914         int ret;
 915         struct ccw1 *ccw;
 916         void *config_area;
 917         unsigned long flags;
 918
 919         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 920         if (!ccw)
 921                 return;
 922
 923         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 924                                             VIRTIO_CCW_CONFIG_SIZE,
 925                                             &ccw->cda);
 926         if (!config_area)
 927                 goto out_free;
 928
 929         /* Read the config area from the host. */
 930         ccw->cmd_code = CCW_CMD_READ_CONF;
 931         ccw->flags = 0;
 932         ccw->count = offset + len;
 933         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 934         if (ret)
 935                 goto out_free;
 936
 937         spin_lock_irqsave(&vcdev->lock, flags);
 938         memcpy(vcdev->config, config_area, offset + len);
 939         if (vcdev->config_ready < offset + len)
 940                 vcdev->config_ready = offset + len;
 941         spin_unlock_irqrestore(&vcdev->lock, flags);
 942         if (buf)
 943                 memcpy(buf, config_area + offset, len);
 944
 945 out_free:
 946         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 947         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 948 }
 949
 950 static void virtio_ccw_set_config(struct virtio_device *vdev,
 951                                   unsigned int offset, const void *buf,
 952                                   unsigned len)
 953 {
 954         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 955         struct ccw1 *ccw;
 956         void *config_area;
 957         unsigned long flags;
 958
 959         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 960         if (!ccw)
 961                 return;
 962
 963         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 964                                             VIRTIO_CCW_CONFIG_SIZE,
 965                                             &ccw->cda);
 966         if (!config_area)
 967                 goto out_free;
 968
 969         /* Make sure we don't overwrite fields. */
 970         if (vcdev->config_ready < offset)
 971                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 972         spin_lock_irqsave(&vcdev->lock, flags);
 973         memcpy(&vcdev->config[offset], buf, len);
 974         /* Write the config area to the host. */
 975         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 976         spin_unlock_irqrestore(&vcdev->lock, flags);
 977         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 978         ccw->flags = 0;
 979         ccw->count = offset + len;
 980         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 981
 982 out_free:
 983         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 984         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 985 }
 986
 987 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 988 {
 989         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 990         u8 old_status = vcdev->dma_area->status;
 991         struct ccw1 *ccw;
 992
 993         if (vcdev->revision < 2)
 994                 return vcdev->dma_area->status;
 995
 996         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 997         if (!ccw)
 998                 return old_status;
 999
1000         ccw->cmd_code = CCW_CMD_READ_STATUS;
1001         ccw->flags = 0;
1002         ccw->count = sizeof(vcdev->dma_area->status);
1003         ccw->cda = status_dma(vcdev);
1004         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
1005 /*
1006  * If the channel program failed (should only happen if the device
1007  * was hotunplugged, and then we clean up via the machine check
1008  * handler anyway), vcdev->dma_area->status was not overwritten and we just
1009  * return the old status, which is fine.
1010 */
1011         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1012
1013         return vcdev->dma_area->status;
1014 }
1015
1016 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
1017 {
1018         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1019         u8 old_status = vcdev->dma_area->status;
1020         struct ccw1 *ccw;
1021         int ret;
1022
1023         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
1024         if (!ccw)
1025                 return;
1026
1027         /* Write the status to the host. */
1028         vcdev->dma_area->status = status;
1029         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
1030         ccw->flags = 0;
1031         ccw->count = sizeof(status);
1032         /* We use ssch for setting the status which is a serializing
1033          * instruction that guarantees the memory writes have
1034          * completed before ssch.
1035          */
1036         ccw->cda = status_dma(vcdev);
1037         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
1038         /* Write failed? We assume status is unchanged. */
1039         if (ret)
1040                 vcdev->dma_area->status = old_status;
1041         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1042 }
1043
1044 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
1045 {
1046         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1047
1048         return dev_name(&vcdev->cdev->dev);
1049 }
1050
1051 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
1052 {
1053         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1054         struct airq_info *info = vcdev->airq_info;
1055
1056         if (info) {
1057                 /*
1058                  * This device uses adapter interrupts: synchronize with
1059                  * vring_interrupt() called by virtio_airq_handler()
1060                  * via the indicator area lock.
1061                  */
1062                 write_lock_irq(&info->lock);
1063                 write_unlock_irq(&info->lock);
1064         } else {
1065                 /* This device uses classic interrupts: synchronize
1066                  * with vring_interrupt() called by
1067                  * virtio_ccw_int_handler() via the per-device
1068                  * irq_lock
1069                  */
1070                 write_lock_irq(&vcdev->irq_lock);
1071                 write_unlock_irq(&vcdev->irq_lock);
1072         }
1073 }
1074
1075 static const struct virtio_config_ops virtio_ccw_config_ops = {
1076         .get_features = virtio_ccw_get_features,
1077         .finalize_features = virtio_ccw_finalize_features,
1078         .get = virtio_ccw_get_config,
1079         .set = virtio_ccw_set_config,
1080         .get_status = virtio_ccw_get_status,
1081         .set_status = virtio_ccw_set_status,
1082         .reset = virtio_ccw_reset,
1083         .find_vqs = virtio_ccw_find_vqs,
1084         .del_vqs = virtio_ccw_del_vqs,
1085         .bus_name = virtio_ccw_bus_name,
1086         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1087 };
1088
1089
1090 /*
1091  * ccw bus driver related functions
1092  */
1093
1094 static void virtio_ccw_release_dev(struct device *_d)
1095 {
1096         struct virtio_device *dev = dev_to_virtio(_d);
1097         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1098
1099         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1100                             sizeof(*vcdev->dma_area));
1101         kfree(vcdev);
1102 }
1103
1104 static int irb_is_error(struct irb *irb)
1105 {
1106         if (scsw_cstat(&irb->scsw) != 0)
1107                 return 1;
1108         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1109                 return 1;
1110         if (scsw_cc(&irb->scsw) != 0)
1111                 return 1;
1112         return 0;
1113 }
1114
1115 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1116                                               int index)
1117 {
1118         struct virtio_ccw_vq_info *info;
1119         unsigned long flags;
1120         struct virtqueue *vq;
1121
1122         vq = NULL;
1123         spin_lock_irqsave(&vcdev->lock, flags);
1124         list_for_each_entry(info, &vcdev->virtqueues, node) {
1125                 if (info->vq->index == index) {
1126                         vq = info->vq;
1127                         break;
1128                 }
1129         }
1130         spin_unlock_irqrestore(&vcdev->lock, flags);
1131         return vq;
1132 }
1133
1134 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1135                                       __u32 activity)
1136 {
1137         if (vcdev->curr_io & activity) {
1138                 switch (activity) {
1139                 case VIRTIO_CCW_DOING_READ_FEAT:
1140                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1141                 case VIRTIO_CCW_DOING_READ_CONFIG:
1142                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1143                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1144                 case VIRTIO_CCW_DOING_READ_STATUS:
1145                 case VIRTIO_CCW_DOING_SET_VQ:
1146                 case VIRTIO_CCW_DOING_SET_IND:
1147                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1148                 case VIRTIO_CCW_DOING_RESET:
1149                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1150                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1151                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1152                         vcdev->curr_io &= ~activity;
1153                         wake_up(&vcdev->wait_q);
1154                         break;
1155                 default:
1156                         /* don't know what to do... */
1157                         dev_warn(&vcdev->cdev->dev,
1158                                  "Suspicious activity '%08x'\n", activity);
1159                         WARN_ON(1);
1160                         break;
1161                 }
1162         }
1163 }
1164
1165 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1166                                    unsigned long intparm,
1167                                    struct irb *irb)
1168 {
1169         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1170         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1171         int i;
1172         struct virtqueue *vq;
1173
1174         if (!vcdev)
1175                 return;
1176         if (IS_ERR(irb)) {
1177                 vcdev->err = PTR_ERR(irb);
1178                 virtio_ccw_check_activity(vcdev, activity);
1179                 /* Don't poke around indicators, something's wrong. */
1180                 return;
1181         }
1182         /* Check if it's a notification from the host. */
1183         if ((intparm == 0) &&
1184             (scsw_stctl(&irb->scsw) ==
1185              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1186                 /* OK */
1187         }
1188         if (irb_is_error(irb)) {
1189                 /* Command reject? */
1190                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1191                     (irb->ecw[0] & SNS0_CMD_REJECT))
1192                         vcdev->err = -EOPNOTSUPP;
1193                 else
1194                         /* Map everything else to -EIO. */
1195                         vcdev->err = -EIO;
1196         }
1197         virtio_ccw_check_activity(vcdev, activity);
1198 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1199         /*
1200          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1201          * disabled here.
1202          */
1203         read_lock(&vcdev->irq_lock);
1204 #endif
1205         for_each_set_bit(i, indicators(vcdev),
1206                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1207                 /* The bit clear must happen before the vring kick. */
1208                 clear_bit(i, indicators(vcdev));
1209                 barrier();
1210                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1211                 vring_interrupt(0, vq);
1212         }
1213 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1214         read_unlock(&vcdev->irq_lock);
1215 #endif
1216         if (test_bit(0, indicators2(vcdev))) {
1217                 virtio_config_changed(&vcdev->vdev);
1218                 clear_bit(0, indicators2(vcdev));
1219         }
1220 }
1221
1222 /*
1223  * We usually want to autoonline all devices, but give the admin
1224  * a way to exempt devices from this.
1225  */
1226 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1227                      (8*sizeof(long)))
1228 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1229
1230 static char *no_auto = "";
1231
1232 module_param(no_auto, charp, 0444);
1233 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1234
1235 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1236 {
1237         struct ccw_dev_id id;
1238
1239         ccw_device_get_id(cdev, &id);
1240         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1241                 return 0;
1242         return 1;
1243 }
1244
1245 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1246 {
1247         struct ccw_device *cdev = data;
1248         int ret;
1249
1250         ret = ccw_device_set_online(cdev);
1251         if (ret)
1252                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1253 }
1254
1255 static int virtio_ccw_probe(struct ccw_device *cdev)
1256 {
1257         cdev->handler = virtio_ccw_int_handler;
1258
1259         if (virtio_ccw_check_autoonline(cdev))
1260                 async_schedule(virtio_ccw_auto_online, cdev);
1261         return 0;
1262 }
1263
1264 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1265 {
1266         unsigned long flags;
1267         struct virtio_ccw_device *vcdev;
1268
1269         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1270         vcdev = dev_get_drvdata(&cdev->dev);
1271         if (!vcdev || vcdev->going_away) {
1272                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1273                 return NULL;
1274         }
1275         vcdev->going_away = true;
1276         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1277         return vcdev;
1278 }
1279
1280 static void virtio_ccw_remove(struct ccw_device *cdev)
1281 {
1282         unsigned long flags;
1283         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1284
1285         if (vcdev && cdev->online) {
1286                 if (vcdev->device_lost)
1287                         virtio_break_device(&vcdev->vdev);
1288                 unregister_virtio_device(&vcdev->vdev);
1289                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1290                 dev_set_drvdata(&cdev->dev, NULL);
1291                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1292         }
1293         cdev->handler = NULL;
1294 }
1295
1296 static int virtio_ccw_offline(struct ccw_device *cdev)
1297 {
1298         unsigned long flags;
1299         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1300
1301         if (!vcdev)
1302                 return 0;
1303         if (vcdev->device_lost)
1304                 virtio_break_device(&vcdev->vdev);
1305         unregister_virtio_device(&vcdev->vdev);
1306         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1307         dev_set_drvdata(&cdev->dev, NULL);
1308         cdev->dev.dma_parms = NULL;
1309         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1310         return 0;
1311 }
1312
1313 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1314 {
1315         struct virtio_rev_info *rev;
1316         struct ccw1 *ccw;
1317         int ret;
1318
1319         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
1320         if (!ccw)
1321                 return -ENOMEM;
1322         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev), &ccw->cda);
1323         if (!rev) {
1324                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1325                 return -ENOMEM;
1326         }
1327
1328         /* Set transport revision */
1329         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1330         ccw->flags = 0;
1331         ccw->count = sizeof(*rev);
1332
1333         vcdev->revision = VIRTIO_CCW_REV_MAX;
1334         do {
1335                 rev->revision = vcdev->revision;
1336                 /* none of our supported revisions carry payload */
1337                 rev->length = 0;
1338                 ret = ccw_io_helper(vcdev, ccw,
1339                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1340                 if (ret == -EOPNOTSUPP) {
1341                         if (vcdev->revision == 0)
1342                                 /*
1343                                  * The host device does not support setting
1344                                  * the revision: let's operate it in legacy
1345                                  * mode.
1346                                  */
1347                                 ret = 0;
1348                         else
1349                                 vcdev->revision--;
1350                 }
1351         } while (ret == -EOPNOTSUPP);
1352
1353         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1354         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1355         return ret;
1356 }
1357
1358 static int virtio_ccw_online(struct ccw_device *cdev)
1359 {
1360         int ret;
1361         struct virtio_ccw_device *vcdev;
1362         unsigned long flags;
1363
1364         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1365         if (!vcdev) {
1366                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1367                 ret = -ENOMEM;
1368                 goto out_free;
1369         }
1370         vcdev->vdev.dev.parent = &cdev->dev;
1371         vcdev->cdev = cdev;
1372         cdev->dev.dma_parms = &vcdev->dma_parms;
1373         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1374                                                 sizeof(*vcdev->dma_area),
1375                                                 &vcdev->dma_area_addr);
1376         if (!vcdev->dma_area) {
1377                 ret = -ENOMEM;
1378                 goto out_free;
1379         }
1380
1381         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1382
1383         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1384         vcdev->vdev.config = &virtio_ccw_config_ops;
1385         init_waitqueue_head(&vcdev->wait_q);
1386         INIT_LIST_HEAD(&vcdev->virtqueues);
1387         spin_lock_init(&vcdev->lock);
1388         rwlock_init(&vcdev->irq_lock);
1389         mutex_init(&vcdev->io_lock);
1390
1391         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1392         dev_set_drvdata(&cdev->dev, vcdev);
1393         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1394         vcdev->vdev.id.vendor = cdev->id.cu_type;
1395         vcdev->vdev.id.device = cdev->id.cu_model;
1396
1397         ret = virtio_ccw_set_transport_rev(vcdev);
1398         if (ret)
1399                 goto out_free;
1400
1401         ret = register_virtio_device(&vcdev->vdev);
1402         if (ret) {
1403                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1404                          ret);
1405                 goto out_put;
1406         }
1407         return 0;
1408 out_put:
1409         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1410         dev_set_drvdata(&cdev->dev, NULL);
1411         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1412         put_device(&vcdev->vdev.dev);
1413         return ret;
1414 out_free:
1415         if (vcdev) {
1416                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1417                                     sizeof(*vcdev->dma_area));
1418         }
1419         kfree(vcdev);
1420         return ret;
1421 }
1422
1423 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1424 {
1425         int rc;
1426         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1427
1428         /*
1429          * Make sure vcdev is set
1430          * i.e. set_offline/remove callback not already running
1431          */
1432         if (!vcdev)
1433                 return NOTIFY_DONE;
1434
1435         switch (event) {
1436         case CIO_GONE:
1437                 vcdev->device_lost = true;
1438                 rc = NOTIFY_DONE;
1439                 break;
1440         case CIO_OPER:
1441                 rc = NOTIFY_OK;
1442                 break;
1443         default:
1444                 rc = NOTIFY_DONE;
1445                 break;
1446         }
1447         return rc;
1448 }
1449
1450 static struct ccw_device_id virtio_ids[] = {
1451         { CCW_DEVICE(0x3832, 0) },
1452         {},
1453 };
1454
1455 static struct ccw_driver virtio_ccw_driver = {
1456         .driver = {
1457                 .owner = THIS_MODULE,
1458                 .name = "virtio_ccw",
1459         },
1460         .ids = virtio_ids,
1461         .probe = virtio_ccw_probe,
1462         .remove = virtio_ccw_remove,
1463         .set_offline = virtio_ccw_offline,
1464         .set_online = virtio_ccw_online,
1465         .notify = virtio_ccw_cio_notify,
1466         .int_class = IRQIO_VIR,
1467 };
1468
1469 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1470                            int max_digit, int max_val)
1471 {
1472         int diff;
1473
1474         diff = 0;
1475         *val = 0;
1476
1477         while (diff <= max_digit) {
1478                 int value = hex_to_bin(**cp);
1479
1480                 if (value < 0)
1481                         break;
1482                 *val = *val * 16 + value;
1483                 (*cp)++;
1484                 diff++;
1485         }
1486
1487         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1488                 return 1;
1489
1490         return 0;
1491 }
1492
1493 static int __init parse_busid(char *str, unsigned int *cssid,
1494                               unsigned int *ssid, unsigned int *devno)
1495 {
1496         char *str_work;
1497         int rc, ret;
1498
1499         rc = 1;
1500
1501         if (*str == '\0')
1502                 goto out;
1503
1504         str_work = str;
1505         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1506         if (ret || (str_work[0] != '.'))
1507                 goto out;
1508         str_work++;
1509         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1510         if (ret || (str_work[0] != '.'))
1511                 goto out;
1512         str_work++;
1513         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1514         if (ret || (str_work[0] != '\0'))
1515                 goto out;
1516
1517         rc = 0;
1518 out:
1519         return rc;
1520 }
1521
1522 static void __init no_auto_parse(void)
1523 {
1524         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1525         char *parm, *str;
1526         int rc;
1527
1528         str = no_auto;
1529         while ((parm = strsep(&str, ","))) {
1530                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1531                                  &from_ssid, &from);
1532                 if (rc)
1533                         continue;
1534                 if (parm != NULL) {
1535                         rc = parse_busid(parm, &to_cssid,
1536                                          &to_ssid, &to);
1537                         if ((from_ssid > to_ssid) ||
1538                             ((from_ssid == to_ssid) && (from > to)))
1539                                 rc = -EINVAL;
1540                 } else {
1541                         to_cssid = from_cssid;
1542                         to_ssid = from_ssid;
1543                         to = from;
1544                 }
1545                 if (rc)
1546                         continue;
1547                 while ((from_ssid < to_ssid) ||
1548                        ((from_ssid == to_ssid) && (from <= to))) {
1549                         set_bit(from, devs_no_auto[from_ssid]);
1550                         from++;
1551                         if (from > __MAX_SUBCHANNEL) {
1552                                 from_ssid++;
1553                                 from = 0;
1554                         }
1555                 }
1556         }
1557 }
1558
1559 static int __init virtio_ccw_init(void)
1560 {
1561         int rc;
1562
1563         /* parse no_auto string before we do anything further */
1564         no_auto_parse();
1565
1566         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1567         if (!summary_indicators)
1568                 return -ENOMEM;
1569         rc = ccw_driver_register(&virtio_ccw_driver);
1570         if (rc)
1571                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1572         return rc;
1573 }
1574 device_initcall(virtio_ccw_init);