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 <cornelia.huck@de.ibm.com>
   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, queue_idx, highest_queue_idx = -1;
 306         struct airq_info *info;
 307         unsigned long *indicator_addr = NULL;
 308         unsigned long bit, flags;
 309
 310         /* Array entries without an actual queue pointer must be ignored. */
 311         for (i = 0; i < nvqs; i++) {
 312                 if (vqs[i])
 313                         highest_queue_idx++;
 314         }
 315
 316         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 317                 mutex_lock(&airq_areas_lock);
 318                 if (!airq_areas[i])
 319                         airq_areas[i] = new_airq_info(i);
 320                 info = airq_areas[i];
 321                 mutex_unlock(&airq_areas_lock);
 322                 if (!info)
 323                         return NULL;
 324                 write_lock_irqsave(&info->lock, flags);
 325                 bit = airq_iv_alloc(info->aiv, highest_queue_idx + 1);
 326                 if (bit == -1UL) {
 327                         /* Not enough vacancies. */
 328                         write_unlock_irqrestore(&info->lock, flags);
 329                         continue;
 330                 }
 331                 *first = bit;
 332                 *airq_info = info;
 333                 indicator_addr = info->aiv->vector;
 334                 for (j = 0, queue_idx = 0; j < nvqs; j++) {
 335                         if (!vqs[j])
 336                                 continue;
 337                         airq_iv_set_ptr(info->aiv, bit + queue_idx++,
 338                                         (unsigned long)vqs[j]);
 339                 }
 340                 write_unlock_irqrestore(&info->lock, flags);
 341         }
 342         return indicator_addr;
 343 }
 344
 345 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 346 {
 347         struct virtio_ccw_vq_info *info;
 348
 349         if (!vcdev->airq_info)
 350                 return;
 351         list_for_each_entry(info, &vcdev->virtqueues, node)
 352                 drop_airq_indicator(info->vq, vcdev->airq_info);
 353 }
 354
 355 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 356 {
 357         unsigned long flags;
 358         __u32 ret;
 359
 360         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 361         if (vcdev->err)
 362                 ret = 0;
 363         else
 364                 ret = vcdev->curr_io & flag;
 365         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 366         return ret;
 367 }
 368
 369 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 370                          struct ccw1 *ccw, __u32 intparm)
 371 {
 372         int ret;
 373         unsigned long flags;
 374         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 375
 376         mutex_lock(&vcdev->io_lock);
 377         do {
 378                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 379                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 380                 if (!ret) {
 381                         if (!vcdev->curr_io)
 382                                 vcdev->err = 0;
 383                         vcdev->curr_io |= flag;
 384                 }
 385                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 386                 cpu_relax();
 387         } while (ret == -EBUSY);
 388         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 389         ret = ret ? ret : vcdev->err;
 390         mutex_unlock(&vcdev->io_lock);
 391         return ret;
 392 }
 393
 394 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 395                                       struct ccw1 *ccw)
 396 {
 397         int ret;
 398         struct virtio_thinint_area *thinint_area = NULL;
 399         struct airq_info *airq_info = vcdev->airq_info;
 400         dma64_t *indicatorp = NULL;
 401
 402         if (vcdev->is_thinint) {
 403                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 404                                                      sizeof(*thinint_area),
 405                                                      &ccw->cda);
 406                 if (!thinint_area)
 407                         return;
 408                 thinint_area->summary_indicator =
 409                         get_summary_indicator_dma(airq_info);
 410                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 411                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 412                 ccw->count = sizeof(*thinint_area);
 413         } else {
 414                 /* payload is the address of the indicators */
 415                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 416                                                    sizeof(*indicatorp),
 417                                                    &ccw->cda);
 418                 if (!indicatorp)
 419                         return;
 420                 *indicatorp = 0;
 421                 ccw->cmd_code = CCW_CMD_SET_IND;
 422                 ccw->count = sizeof(*indicatorp);
 423         }
 424         /* Deregister indicators from host. */
 425         *indicators(vcdev) = 0;
 426         ccw->flags = 0;
 427         ret = ccw_io_helper(vcdev, ccw,
 428                             vcdev->is_thinint ?
 429                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 430                             VIRTIO_CCW_DOING_SET_IND);
 431         if (ret && (ret != -ENODEV))
 432                 dev_info(&vcdev->cdev->dev,
 433                          "Failed to deregister indicators (%d)\n", ret);
 434         else if (vcdev->is_thinint)
 435                 virtio_ccw_drop_indicators(vcdev);
 436         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(*indicatorp));
 437         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 438 }
 439
 440 static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data)
 441 {
 442         struct virtio_ccw_vq_info *info = vq->priv;
 443         struct virtio_ccw_device *vcdev;
 444         struct subchannel_id schid;
 445
 446         vcdev = to_vc_device(info->vq->vdev);
 447         ccw_device_get_schid(vcdev->cdev, &schid);
 448         BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
 449         info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
 450                                       *((unsigned int *)&schid),
 451                                       data, info->cookie);
 452         if (info->cookie < 0)
 453                 return false;
 454         return true;
 455 }
 456
 457 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 458 {
 459         return virtio_ccw_do_kvm_notify(vq, vq->index);
 460 }
 461
 462 static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq)
 463 {
 464         return virtio_ccw_do_kvm_notify(vq, vring_notification_data(vq));
 465 }
 466
 467 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 468                                    struct ccw1 *ccw, int index)
 469 {
 470         int ret;
 471
 472         vcdev->dma_area->config_block.index = index;
 473         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 474         ccw->flags = 0;
 475         ccw->count = sizeof(struct vq_config_block);
 476         ccw->cda = config_block_dma(vcdev);
 477         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 478         if (ret)
 479                 return ret;
 480         return vcdev->dma_area->config_block.num ?: -ENOENT;
 481 }
 482
 483 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 484 {
 485         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 486         struct virtio_ccw_vq_info *info = vq->priv;
 487         unsigned long flags;
 488         int ret;
 489         unsigned int index = vq->index;
 490
 491         /* Remove from our list. */
 492         spin_lock_irqsave(&vcdev->lock, flags);
 493         list_del(&info->node);
 494         spin_unlock_irqrestore(&vcdev->lock, flags);
 495
 496         /* Release from host. */
 497         if (vcdev->revision == 0) {
 498                 info->info_block->l.queue = 0;
 499                 info->info_block->l.align = 0;
 500                 info->info_block->l.index = index;
 501                 info->info_block->l.num = 0;
 502                 ccw->count = sizeof(info->info_block->l);
 503         } else {
 504                 info->info_block->s.desc = 0;
 505                 info->info_block->s.index = index;
 506                 info->info_block->s.num = 0;
 507                 info->info_block->s.avail = 0;
 508                 info->info_block->s.used = 0;
 509                 ccw->count = sizeof(info->info_block->s);
 510         }
 511         ccw->cmd_code = CCW_CMD_SET_VQ;
 512         ccw->flags = 0;
 513         ccw->cda = info->info_block_addr;
 514         ret = ccw_io_helper(vcdev, ccw,
 515                             VIRTIO_CCW_DOING_SET_VQ | index);
 516         /*
 517          * -ENODEV isn't considered an error: The device is gone anyway.
 518          * This may happen on device detach.
 519          */
 520         if (ret && (ret != -ENODEV))
 521                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 522                          ret, index);
 523
 524         vring_del_virtqueue(vq);
 525         ccw_device_dma_free(vcdev->cdev, info->info_block,
 526                             sizeof(*info->info_block));
 527         kfree(info);
 528 }
 529
 530 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 531 {
 532         struct virtqueue *vq, *n;
 533         struct ccw1 *ccw;
 534         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 535
 536         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 537         if (!ccw)
 538                 return;
 539
 540         virtio_ccw_drop_indicator(vcdev, ccw);
 541
 542         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 543                 virtio_ccw_del_vq(vq, ccw);
 544
 545         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 546 }
 547
 548 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 549                                              int i, vq_callback_t *callback,
 550                                              const char *name, bool ctx,
 551                                              struct ccw1 *ccw)
 552 {
 553         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 554         bool (*notify)(struct virtqueue *vq);
 555         int err;
 556         struct virtqueue *vq = NULL;
 557         struct virtio_ccw_vq_info *info;
 558         u64 queue;
 559         unsigned long flags;
 560         bool may_reduce;
 561
 562         if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
 563                 notify = virtio_ccw_kvm_notify_with_data;
 564         else
 565                 notify = virtio_ccw_kvm_notify;
 566
 567         /* Allocate queue. */
 568         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 569         if (!info) {
 570                 dev_warn(&vcdev->cdev->dev, "no info\n");
 571                 err = -ENOMEM;
 572                 goto out_err;
 573         }
 574         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 575                                                  sizeof(*info->info_block),
 576                                                  &info->info_block_addr);
 577         if (!info->info_block) {
 578                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 579                 err = -ENOMEM;
 580                 goto out_err;
 581         }
 582         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 583         if (info->num < 0) {
 584                 err = info->num;
 585                 goto out_err;
 586         }
 587         may_reduce = vcdev->revision > 0;
 588         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 589                                     vdev, true, may_reduce, ctx,
 590                                     notify, callback, name);
 591
 592         if (!vq) {
 593                 /* For now, we fail if we can't get the requested size. */
 594                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 595                 err = -ENOMEM;
 596                 goto out_err;
 597         }
 598
 599         vq->num_max = info->num;
 600
 601         /* it may have been reduced */
 602         info->num = virtqueue_get_vring_size(vq);
 603
 604         /* Register it with the host. */
 605         queue = virtqueue_get_desc_addr(vq);
 606         if (vcdev->revision == 0) {
 607                 info->info_block->l.queue = u64_to_dma64(queue);
 608                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 609                 info->info_block->l.index = i;
 610                 info->info_block->l.num = info->num;
 611                 ccw->count = sizeof(info->info_block->l);
 612         } else {
 613                 info->info_block->s.desc = u64_to_dma64(queue);
 614                 info->info_block->s.index = i;
 615                 info->info_block->s.num = info->num;
 616                 info->info_block->s.avail = u64_to_dma64(virtqueue_get_avail_addr(vq));
 617                 info->info_block->s.used = u64_to_dma64(virtqueue_get_used_addr(vq));
 618                 ccw->count = sizeof(info->info_block->s);
 619         }
 620         ccw->cmd_code = CCW_CMD_SET_VQ;
 621         ccw->flags = 0;
 622         ccw->cda = info->info_block_addr;
 623         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 624         if (err) {
 625                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 626                 goto out_err;
 627         }
 628
 629         info->vq = vq;
 630         vq->priv = info;
 631
 632         /* Save it to our list. */
 633         spin_lock_irqsave(&vcdev->lock, flags);
 634         list_add(&info->node, &vcdev->virtqueues);
 635         spin_unlock_irqrestore(&vcdev->lock, flags);
 636
 637         return vq;
 638
 639 out_err:
 640         if (vq)
 641                 vring_del_virtqueue(vq);
 642         if (info) {
 643                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 644                                     sizeof(*info->info_block));
 645         }
 646         kfree(info);
 647         return ERR_PTR(err);
 648 }
 649
 650 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 651                                            struct virtqueue *vqs[], int nvqs,
 652                                            struct ccw1 *ccw)
 653 {
 654         int ret;
 655         struct virtio_thinint_area *thinint_area = NULL;
 656         unsigned long *indicator_addr;
 657         struct airq_info *info;
 658
 659         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 660                                              sizeof(*thinint_area),
 661                                              &ccw->cda);
 662         if (!thinint_area) {
 663                 ret = -ENOMEM;
 664                 goto out;
 665         }
 666         /* Try to get an indicator. */
 667         indicator_addr = get_airq_indicator(vqs, nvqs,
 668                                             &thinint_area->bit_nr,
 669                                             &vcdev->airq_info);
 670         if (!indicator_addr) {
 671                 ret = -ENOSPC;
 672                 goto out;
 673         }
 674         thinint_area->indicator = virt_to_dma64(indicator_addr);
 675         info = vcdev->airq_info;
 676         thinint_area->summary_indicator = get_summary_indicator_dma(info);
 677         thinint_area->isc = VIRTIO_AIRQ_ISC;
 678         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 679         ccw->flags = CCW_FLAG_SLI;
 680         ccw->count = sizeof(*thinint_area);
 681         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 682         if (ret) {
 683                 if (ret == -EOPNOTSUPP) {
 684                         /*
 685                          * The host does not support adapter interrupts
 686                          * for virtio-ccw, stop trying.
 687                          */
 688                         virtio_ccw_use_airq = 0;
 689                         pr_info("Adapter interrupts unsupported on host\n");
 690                 } else
 691                         dev_warn(&vcdev->cdev->dev,
 692                                  "enabling adapter interrupts = %d\n", ret);
 693                 virtio_ccw_drop_indicators(vcdev);
 694         }
 695 out:
 696         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 697         return ret;
 698 }
 699
 700 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 701                                struct virtqueue *vqs[],
 702                                struct virtqueue_info vqs_info[],
 703                                struct irq_affinity *desc)
 704 {
 705         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 706         dma64_t *indicatorp = NULL;
 707         int ret, i, queue_idx = 0;
 708         struct ccw1 *ccw;
 709         dma32_t indicatorp_dma = 0;
 710
 711         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 712         if (!ccw)
 713                 return -ENOMEM;
 714
 715         for (i = 0; i < nvqs; ++i) {
 716                 struct virtqueue_info *vqi = &vqs_info[i];
 717
 718                 if (!vqi->name) {
 719                         vqs[i] = NULL;
 720                         continue;
 721                 }
 722
 723                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, vqi->callback,
 724                                              vqi->name, vqi->ctx, ccw);
 725                 if (IS_ERR(vqs[i])) {
 726                         ret = PTR_ERR(vqs[i]);
 727                         vqs[i] = NULL;
 728                         goto out;
 729                 }
 730         }
 731         ret = -ENOMEM;
 732         /*
 733          * We need a data area under 2G to communicate. Our payload is
 734          * the address of the indicators.
 735         */
 736         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 737                                            sizeof(*indicatorp),
 738                                            &indicatorp_dma);
 739         if (!indicatorp)
 740                 goto out;
 741         *indicatorp = indicators_dma(vcdev);
 742         if (vcdev->is_thinint) {
 743                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 744                 if (ret)
 745                         /* no error, just fall back to legacy interrupts */
 746                         vcdev->is_thinint = false;
 747         }
 748         ccw->cda = indicatorp_dma;
 749         if (!vcdev->is_thinint) {
 750                 /* Register queue indicators with host. */
 751                 *indicators(vcdev) = 0;
 752                 ccw->cmd_code = CCW_CMD_SET_IND;
 753                 ccw->flags = 0;
 754                 ccw->count = sizeof(*indicatorp);
 755                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 756                 if (ret)
 757                         goto out;
 758         }
 759         /* Register indicators2 with host for config changes */
 760         *indicatorp = indicators2_dma(vcdev);
 761         *indicators2(vcdev) = 0;
 762         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 763         ccw->flags = 0;
 764         ccw->count = sizeof(*indicatorp);
 765         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 766         if (ret)
 767                 goto out;
 768
 769         if (indicatorp)
 770                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 771                                     sizeof(*indicatorp));
 772         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 773         return 0;
 774 out:
 775         if (indicatorp)
 776                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 777                                     sizeof(*indicatorp));
 778         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 779         virtio_ccw_del_vqs(vdev);
 780         return ret;
 781 }
 782
 783 static void virtio_ccw_reset(struct virtio_device *vdev)
 784 {
 785         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 786         struct ccw1 *ccw;
 787
 788         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 789         if (!ccw)
 790                 return;
 791
 792         /* Zero status bits. */
 793         vcdev->dma_area->status = 0;
 794
 795         /* Send a reset ccw on device. */
 796         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 797         ccw->flags = 0;
 798         ccw->count = 0;
 799         ccw->cda = 0;
 800         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 801         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 802 }
 803
 804 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 805 {
 806         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 807         struct virtio_feature_desc *features;
 808         int ret;
 809         u64 rc;
 810         struct ccw1 *ccw;
 811
 812         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 813         if (!ccw)
 814                 return 0;
 815
 816         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
 817                                          &ccw->cda);
 818         if (!features) {
 819                 rc = 0;
 820                 goto out_free;
 821         }
 822         /* Read the feature bits from the host. */
 823         features->index = 0;
 824         ccw->cmd_code = CCW_CMD_READ_FEAT;
 825         ccw->flags = 0;
 826         ccw->count = sizeof(*features);
 827         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 828         if (ret) {
 829                 rc = 0;
 830                 goto out_free;
 831         }
 832
 833         rc = le32_to_cpu(features->features);
 834
 835         if (vcdev->revision == 0)
 836                 goto out_free;
 837
 838         /* Read second half of the feature bits from the host. */
 839         features->index = 1;
 840         ccw->cmd_code = CCW_CMD_READ_FEAT;
 841         ccw->flags = 0;
 842         ccw->count = sizeof(*features);
 843         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 844         if (ret == 0)
 845                 rc |= (u64)le32_to_cpu(features->features) << 32;
 846
 847 out_free:
 848         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 849         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 850         return rc;
 851 }
 852
 853 static void ccw_transport_features(struct virtio_device *vdev)
 854 {
 855         /*
 856          * Currently nothing to do here.
 857          */
 858 }
 859
 860 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 861 {
 862         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 863         struct virtio_feature_desc *features;
 864         struct ccw1 *ccw;
 865         int ret;
 866
 867         if (vcdev->revision >= 1 &&
 868             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 869                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 870                         "but does not have VIRTIO_F_VERSION_1\n");
 871                 return -EINVAL;
 872         }
 873
 874         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 875         if (!ccw)
 876                 return -ENOMEM;
 877
 878         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features),
 879                                          &ccw->cda);
 880         if (!features) {
 881                 ret = -ENOMEM;
 882                 goto out_free;
 883         }
 884         /* Give virtio_ring a chance to accept features. */
 885         vring_transport_features(vdev);
 886
 887         /* Give virtio_ccw a chance to accept features. */
 888         ccw_transport_features(vdev);
 889
 890         features->index = 0;
 891         features->features = cpu_to_le32((u32)vdev->features);
 892         /* Write the first half of the feature bits to the host. */
 893         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 894         ccw->flags = 0;
 895         ccw->count = sizeof(*features);
 896         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 897         if (ret)
 898                 goto out_free;
 899
 900         if (vcdev->revision == 0)
 901                 goto out_free;
 902
 903         features->index = 1;
 904         features->features = cpu_to_le32(vdev->features >> 32);
 905         /* Write the second half of the feature bits to the host. */
 906         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 907         ccw->flags = 0;
 908         ccw->count = sizeof(*features);
 909         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 910
 911 out_free:
 912         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 913         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 914
 915         return ret;
 916 }
 917
 918 static void virtio_ccw_get_config(struct virtio_device *vdev,
 919                                   unsigned int offset, void *buf, unsigned len)
 920 {
 921         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 922         int ret;
 923         struct ccw1 *ccw;
 924         void *config_area;
 925         unsigned long flags;
 926
 927         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 928         if (!ccw)
 929                 return;
 930
 931         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 932                                             VIRTIO_CCW_CONFIG_SIZE,
 933                                             &ccw->cda);
 934         if (!config_area)
 935                 goto out_free;
 936
 937         /* Read the config area from the host. */
 938         ccw->cmd_code = CCW_CMD_READ_CONF;
 939         ccw->flags = 0;
 940         ccw->count = offset + len;
 941         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 942         if (ret)
 943                 goto out_free;
 944
 945         spin_lock_irqsave(&vcdev->lock, flags);
 946         memcpy(vcdev->config, config_area, offset + len);
 947         if (vcdev->config_ready < offset + len)
 948                 vcdev->config_ready = offset + len;
 949         spin_unlock_irqrestore(&vcdev->lock, flags);
 950         if (buf)
 951                 memcpy(buf, config_area + offset, len);
 952
 953 out_free:
 954         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 955         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 956 }
 957
 958 static void virtio_ccw_set_config(struct virtio_device *vdev,
 959                                   unsigned int offset, const void *buf,
 960                                   unsigned len)
 961 {
 962         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 963         struct ccw1 *ccw;
 964         void *config_area;
 965         unsigned long flags;
 966
 967         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
 968         if (!ccw)
 969                 return;
 970
 971         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 972                                             VIRTIO_CCW_CONFIG_SIZE,
 973                                             &ccw->cda);
 974         if (!config_area)
 975                 goto out_free;
 976
 977         /* Make sure we don't overwrite fields. */
 978         if (vcdev->config_ready < offset)
 979                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 980         spin_lock_irqsave(&vcdev->lock, flags);
 981         memcpy(&vcdev->config[offset], buf, len);
 982         /* Write the config area to the host. */
 983         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 984         spin_unlock_irqrestore(&vcdev->lock, flags);
 985         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 986         ccw->flags = 0;
 987         ccw->count = offset + len;
 988         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 989
 990 out_free:
 991         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 992         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 993 }
 994
 995 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 996 {
 997         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 998         u8 old_status = vcdev->dma_area->status;
 999         struct ccw1 *ccw;
1000
1001         if (vcdev->revision < 2)
1002                 return vcdev->dma_area->status;
1003
1004         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
1005         if (!ccw)
1006                 return old_status;
1007
1008         ccw->cmd_code = CCW_CMD_READ_STATUS;
1009         ccw->flags = 0;
1010         ccw->count = sizeof(vcdev->dma_area->status);
1011         ccw->cda = status_dma(vcdev);
1012         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
1013 /*
1014  * If the channel program failed (should only happen if the device
1015  * was hotunplugged, and then we clean up via the machine check
1016  * handler anyway), vcdev->dma_area->status was not overwritten and we just
1017  * return the old status, which is fine.
1018 */
1019         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1020
1021         return vcdev->dma_area->status;
1022 }
1023
1024 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
1025 {
1026         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1027         u8 old_status = vcdev->dma_area->status;
1028         struct ccw1 *ccw;
1029         int ret;
1030
1031         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
1032         if (!ccw)
1033                 return;
1034
1035         /* Write the status to the host. */
1036         vcdev->dma_area->status = status;
1037         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
1038         ccw->flags = 0;
1039         ccw->count = sizeof(status);
1040         /* We use ssch for setting the status which is a serializing
1041          * instruction that guarantees the memory writes have
1042          * completed before ssch.
1043          */
1044         ccw->cda = status_dma(vcdev);
1045         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
1046         /* Write failed? We assume status is unchanged. */
1047         if (ret)
1048                 vcdev->dma_area->status = old_status;
1049         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1050 }
1051
1052 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
1053 {
1054         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1055
1056         return dev_name(&vcdev->cdev->dev);
1057 }
1058
1059 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
1060 {
1061         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1062         struct airq_info *info = vcdev->airq_info;
1063
1064         if (info) {
1065                 /*
1066                  * This device uses adapter interrupts: synchronize with
1067                  * vring_interrupt() called by virtio_airq_handler()
1068                  * via the indicator area lock.
1069                  */
1070                 write_lock_irq(&info->lock);
1071                 write_unlock_irq(&info->lock);
1072         } else {
1073                 /* This device uses classic interrupts: synchronize
1074                  * with vring_interrupt() called by
1075                  * virtio_ccw_int_handler() via the per-device
1076                  * irq_lock
1077                  */
1078                 write_lock_irq(&vcdev->irq_lock);
1079                 write_unlock_irq(&vcdev->irq_lock);
1080         }
1081 }
1082
1083 static const struct virtio_config_ops virtio_ccw_config_ops = {
1084         .get_features = virtio_ccw_get_features,
1085         .finalize_features = virtio_ccw_finalize_features,
1086         .get = virtio_ccw_get_config,
1087         .set = virtio_ccw_set_config,
1088         .get_status = virtio_ccw_get_status,
1089         .set_status = virtio_ccw_set_status,
1090         .reset = virtio_ccw_reset,
1091         .find_vqs = virtio_ccw_find_vqs,
1092         .del_vqs = virtio_ccw_del_vqs,
1093         .bus_name = virtio_ccw_bus_name,
1094         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1095 };
1096
1097
1098 /*
1099  * ccw bus driver related functions
1100  */
1101
1102 static void virtio_ccw_release_dev(struct device *_d)
1103 {
1104         struct virtio_device *dev = dev_to_virtio(_d);
1105         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1106
1107         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1108                             sizeof(*vcdev->dma_area));
1109         kfree(vcdev);
1110 }
1111
1112 static int irb_is_error(struct irb *irb)
1113 {
1114         if (scsw_cstat(&irb->scsw) != 0)
1115                 return 1;
1116         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1117                 return 1;
1118         if (scsw_cc(&irb->scsw) != 0)
1119                 return 1;
1120         return 0;
1121 }
1122
1123 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1124                                               int index)
1125 {
1126         struct virtio_ccw_vq_info *info;
1127         unsigned long flags;
1128         struct virtqueue *vq;
1129
1130         vq = NULL;
1131         spin_lock_irqsave(&vcdev->lock, flags);
1132         list_for_each_entry(info, &vcdev->virtqueues, node) {
1133                 if (info->vq->index == index) {
1134                         vq = info->vq;
1135                         break;
1136                 }
1137         }
1138         spin_unlock_irqrestore(&vcdev->lock, flags);
1139         return vq;
1140 }
1141
1142 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1143                                       __u32 activity)
1144 {
1145         if (vcdev->curr_io & activity) {
1146                 switch (activity) {
1147                 case VIRTIO_CCW_DOING_READ_FEAT:
1148                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1149                 case VIRTIO_CCW_DOING_READ_CONFIG:
1150                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1151                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1152                 case VIRTIO_CCW_DOING_READ_STATUS:
1153                 case VIRTIO_CCW_DOING_SET_VQ:
1154                 case VIRTIO_CCW_DOING_SET_IND:
1155                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1156                 case VIRTIO_CCW_DOING_RESET:
1157                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1158                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1159                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1160                         vcdev->curr_io &= ~activity;
1161                         wake_up(&vcdev->wait_q);
1162                         break;
1163                 default:
1164                         /* don't know what to do... */
1165                         dev_warn(&vcdev->cdev->dev,
1166                                  "Suspicious activity '%08x'\n", activity);
1167                         WARN_ON(1);
1168                         break;
1169                 }
1170         }
1171 }
1172
1173 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1174                                    unsigned long intparm,
1175                                    struct irb *irb)
1176 {
1177         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1178         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1179         int i;
1180         struct virtqueue *vq;
1181
1182         if (!vcdev)
1183                 return;
1184         if (IS_ERR(irb)) {
1185                 vcdev->err = PTR_ERR(irb);
1186                 virtio_ccw_check_activity(vcdev, activity);
1187                 /* Don't poke around indicators, something's wrong. */
1188                 return;
1189         }
1190         /* Check if it's a notification from the host. */
1191         if ((intparm == 0) &&
1192             (scsw_stctl(&irb->scsw) ==
1193              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1194                 /* OK */
1195         }
1196         if (irb_is_error(irb)) {
1197                 /* Command reject? */
1198                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1199                     (irb->ecw[0] & SNS0_CMD_REJECT))
1200                         vcdev->err = -EOPNOTSUPP;
1201                 else
1202                         /* Map everything else to -EIO. */
1203                         vcdev->err = -EIO;
1204         }
1205         virtio_ccw_check_activity(vcdev, activity);
1206 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1207         /*
1208          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1209          * disabled here.
1210          */
1211         read_lock(&vcdev->irq_lock);
1212 #endif
1213         for_each_set_bit(i, indicators(vcdev),
1214                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1215                 /* The bit clear must happen before the vring kick. */
1216                 clear_bit(i, indicators(vcdev));
1217                 barrier();
1218                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1219                 vring_interrupt(0, vq);
1220         }
1221 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1222         read_unlock(&vcdev->irq_lock);
1223 #endif
1224         if (test_bit(0, indicators2(vcdev))) {
1225                 virtio_config_changed(&vcdev->vdev);
1226                 clear_bit(0, indicators2(vcdev));
1227         }
1228 }
1229
1230 /*
1231  * We usually want to autoonline all devices, but give the admin
1232  * a way to exempt devices from this.
1233  */
1234 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1235                      (8*sizeof(long)))
1236 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1237
1238 static char *no_auto = "";
1239
1240 module_param(no_auto, charp, 0444);
1241 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1242
1243 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1244 {
1245         struct ccw_dev_id id;
1246
1247         ccw_device_get_id(cdev, &id);
1248         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1249                 return 0;
1250         return 1;
1251 }
1252
1253 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1254 {
1255         struct ccw_device *cdev = data;
1256         int ret;
1257
1258         ret = ccw_device_set_online(cdev);
1259         if (ret)
1260                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1261 }
1262
1263 static int virtio_ccw_probe(struct ccw_device *cdev)
1264 {
1265         cdev->handler = virtio_ccw_int_handler;
1266
1267         if (virtio_ccw_check_autoonline(cdev))
1268                 async_schedule(virtio_ccw_auto_online, cdev);
1269         return 0;
1270 }
1271
1272 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1273 {
1274         unsigned long flags;
1275         struct virtio_ccw_device *vcdev;
1276
1277         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1278         vcdev = dev_get_drvdata(&cdev->dev);
1279         if (!vcdev || vcdev->going_away) {
1280                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1281                 return NULL;
1282         }
1283         vcdev->going_away = true;
1284         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1285         return vcdev;
1286 }
1287
1288 static void virtio_ccw_remove(struct ccw_device *cdev)
1289 {
1290         unsigned long flags;
1291         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1292
1293         if (vcdev && cdev->online) {
1294                 if (vcdev->device_lost)
1295                         virtio_break_device(&vcdev->vdev);
1296                 unregister_virtio_device(&vcdev->vdev);
1297                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1298                 dev_set_drvdata(&cdev->dev, NULL);
1299                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1300         }
1301         cdev->handler = NULL;
1302 }
1303
1304 static int virtio_ccw_offline(struct ccw_device *cdev)
1305 {
1306         unsigned long flags;
1307         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1308
1309         if (!vcdev)
1310                 return 0;
1311         if (vcdev->device_lost)
1312                 virtio_break_device(&vcdev->vdev);
1313         unregister_virtio_device(&vcdev->vdev);
1314         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1315         dev_set_drvdata(&cdev->dev, NULL);
1316         cdev->dev.dma_parms = NULL;
1317         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1318         return 0;
1319 }
1320
1321 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1322 {
1323         struct virtio_rev_info *rev;
1324         struct ccw1 *ccw;
1325         int ret;
1326
1327         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw), NULL);
1328         if (!ccw)
1329                 return -ENOMEM;
1330         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev), &ccw->cda);
1331         if (!rev) {
1332                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1333                 return -ENOMEM;
1334         }
1335
1336         /* Set transport revision */
1337         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1338         ccw->flags = 0;
1339         ccw->count = sizeof(*rev);
1340
1341         vcdev->revision = VIRTIO_CCW_REV_MAX;
1342         do {
1343                 rev->revision = vcdev->revision;
1344                 /* none of our supported revisions carry payload */
1345                 rev->length = 0;
1346                 ret = ccw_io_helper(vcdev, ccw,
1347                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1348                 if (ret == -EOPNOTSUPP) {
1349                         if (vcdev->revision == 0)
1350                                 /*
1351                                  * The host device does not support setting
1352                                  * the revision: let's operate it in legacy
1353                                  * mode.
1354                                  */
1355                                 ret = 0;
1356                         else
1357                                 vcdev->revision--;
1358                 }
1359         } while (ret == -EOPNOTSUPP);
1360
1361         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1362         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1363         return ret;
1364 }
1365
1366 static int virtio_ccw_online(struct ccw_device *cdev)
1367 {
1368         int ret;
1369         struct virtio_ccw_device *vcdev;
1370         unsigned long flags;
1371
1372         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1373         if (!vcdev) {
1374                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1375                 ret = -ENOMEM;
1376                 goto out_free;
1377         }
1378         vcdev->vdev.dev.parent = &cdev->dev;
1379         vcdev->cdev = cdev;
1380         cdev->dev.dma_parms = &vcdev->dma_parms;
1381         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1382                                                 sizeof(*vcdev->dma_area),
1383                                                 &vcdev->dma_area_addr);
1384         if (!vcdev->dma_area) {
1385                 ret = -ENOMEM;
1386                 goto out_free;
1387         }
1388
1389         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1390
1391         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1392         vcdev->vdev.config = &virtio_ccw_config_ops;
1393         init_waitqueue_head(&vcdev->wait_q);
1394         INIT_LIST_HEAD(&vcdev->virtqueues);
1395         spin_lock_init(&vcdev->lock);
1396         rwlock_init(&vcdev->irq_lock);
1397         mutex_init(&vcdev->io_lock);
1398
1399         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1400         dev_set_drvdata(&cdev->dev, vcdev);
1401         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1402         vcdev->vdev.id.vendor = cdev->id.cu_type;
1403         vcdev->vdev.id.device = cdev->id.cu_model;
1404
1405         ret = virtio_ccw_set_transport_rev(vcdev);
1406         if (ret)
1407                 goto out_free;
1408
1409         ret = register_virtio_device(&vcdev->vdev);
1410         if (ret) {
1411                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1412                          ret);
1413                 goto out_put;
1414         }
1415         return 0;
1416 out_put:
1417         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1418         dev_set_drvdata(&cdev->dev, NULL);
1419         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1420         put_device(&vcdev->vdev.dev);
1421         return ret;
1422 out_free:
1423         if (vcdev) {
1424                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1425                                     sizeof(*vcdev->dma_area));
1426         }
1427         kfree(vcdev);
1428         return ret;
1429 }
1430
1431 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1432 {
1433         int rc;
1434         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1435
1436         /*
1437          * Make sure vcdev is set
1438          * i.e. set_offline/remove callback not already running
1439          */
1440         if (!vcdev)
1441                 return NOTIFY_DONE;
1442
1443         switch (event) {
1444         case CIO_GONE:
1445                 vcdev->device_lost = true;
1446                 rc = NOTIFY_DONE;
1447                 break;
1448         case CIO_OPER:
1449                 rc = NOTIFY_OK;
1450                 break;
1451         default:
1452                 rc = NOTIFY_DONE;
1453                 break;
1454         }
1455         return rc;
1456 }
1457
1458 static struct ccw_device_id virtio_ids[] = {
1459         { CCW_DEVICE(0x3832, 0) },
1460         {},
1461 };
1462
1463 static struct ccw_driver virtio_ccw_driver = {
1464         .driver = {
1465                 .owner = THIS_MODULE,
1466                 .name = "virtio_ccw",
1467         },
1468         .ids = virtio_ids,
1469         .probe = virtio_ccw_probe,
1470         .remove = virtio_ccw_remove,
1471         .set_offline = virtio_ccw_offline,
1472         .set_online = virtio_ccw_online,
1473         .notify = virtio_ccw_cio_notify,
1474         .int_class = IRQIO_VIR,
1475 };
1476
1477 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1478                            int max_digit, int max_val)
1479 {
1480         int diff;
1481
1482         diff = 0;
1483         *val = 0;
1484
1485         while (diff <= max_digit) {
1486                 int value = hex_to_bin(**cp);
1487
1488                 if (value < 0)
1489                         break;
1490                 *val = *val * 16 + value;
1491                 (*cp)++;
1492                 diff++;
1493         }
1494
1495         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1496                 return 1;
1497
1498         return 0;
1499 }
1500
1501 static int __init parse_busid(char *str, unsigned int *cssid,
1502                               unsigned int *ssid, unsigned int *devno)
1503 {
1504         char *str_work;
1505         int rc, ret;
1506
1507         rc = 1;
1508
1509         if (*str == '\0')
1510                 goto out;
1511
1512         str_work = str;
1513         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1514         if (ret || (str_work[0] != '.'))
1515                 goto out;
1516         str_work++;
1517         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1518         if (ret || (str_work[0] != '.'))
1519                 goto out;
1520         str_work++;
1521         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1522         if (ret || (str_work[0] != '\0'))
1523                 goto out;
1524
1525         rc = 0;
1526 out:
1527         return rc;
1528 }
1529
1530 static void __init no_auto_parse(void)
1531 {
1532         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1533         char *parm, *str;
1534         int rc;
1535
1536         str = no_auto;
1537         while ((parm = strsep(&str, ","))) {
1538                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1539                                  &from_ssid, &from);
1540                 if (rc)
1541                         continue;
1542                 if (parm != NULL) {
1543                         rc = parse_busid(parm, &to_cssid,
1544                                          &to_ssid, &to);
1545                         if ((from_ssid > to_ssid) ||
1546                             ((from_ssid == to_ssid) && (from > to)))
1547                                 rc = -EINVAL;
1548                 } else {
1549                         to_cssid = from_cssid;
1550                         to_ssid = from_ssid;
1551                         to = from;
1552                 }
1553                 if (rc)
1554                         continue;
1555                 while ((from_ssid < to_ssid) ||
1556                        ((from_ssid == to_ssid) && (from <= to))) {
1557                         set_bit(from, devs_no_auto[from_ssid]);
1558                         from++;
1559                         if (from > __MAX_SUBCHANNEL) {
1560                                 from_ssid++;
1561                                 from = 0;
1562                         }
1563                 }
1564         }
1565 }
1566
1567 static int __init virtio_ccw_init(void)
1568 {
1569         int rc;
1570
1571         /* parse no_auto string before we do anything further */
1572         no_auto_parse();
1573
1574         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1575         if (!summary_indicators)
1576                 return -ENOMEM;
1577         rc = ccw_driver_register(&virtio_ccw_driver);
1578         if (rc)
1579                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1580         return rc;
1581 }
1582 device_initcall(virtio_ccw_init);