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