drivers/s390/virtio/virtio_ccw.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ccw based virtio transport
   4  *
   5  * Copyright IBM Corp. 2012, 2014
   6  *
   7  *    Author(s): Cornelia Huck <[email protected]>
   8  */
   9
  10 #include <linux/kernel_stat.h>
  11 #include <linux/init.h>
  12 #include <linux/memblock.h>
  13 #include <linux/err.h>
  14 #include <linux/virtio.h>
  15 #include <linux/virtio_config.h>
  16 #include <linux/slab.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/virtio_ring.h>
  19 #include <linux/pfn.h>
  20 #include <linux/async.h>
  21 #include <linux/wait.h>
  22 #include <linux/list.h>
  23 #include <linux/bitops.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/io.h>
  26 #include <linux/kvm_para.h>
  27 #include <linux/notifier.h>
  28 #include <asm/diag.h>
  29 #include <asm/setup.h>
  30 #include <asm/irq.h>
  31 #include <asm/cio.h>
  32 #include <asm/ccwdev.h>
  33 #include <asm/virtio-ccw.h>
  34 #include <asm/isc.h>
  35 #include <asm/airq.h>
  36 #include <asm/tpi.h>
  37
  38 /*
  39  * virtio related functions
  40  */
  41
  42 struct vq_config_block {
  43         __u16 index;
  44         __u16 num;
  45 } __packed;
  46
  47 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  48 /* same as PCI config space size, should be enough for all drivers */
  49
  50 struct vcdev_dma_area {
  51         unsigned long indicators;
  52         unsigned long indicators2;
  53         struct vq_config_block config_block;
  54         __u8 status;
  55 };
  56
  57 struct virtio_ccw_device {
  58         struct virtio_device vdev;
  59         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  60         struct ccw_device *cdev;
  61         __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 };
  76
  77 static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  78 {
  79         return &vcdev->dma_area->indicators;
  80 }
  81
  82 static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  83 {
  84         return &vcdev->dma_area->indicators2;
  85 }
  86
  87 struct vq_info_block_legacy {
  88         __u64 queue;
  89         __u32 align;
  90         __u16 index;
  91         __u16 num;
  92 } __packed;
  93
  94 struct vq_info_block {
  95         __u64 desc;
  96         __u32 res0;
  97         __u16 index;
  98         __u16 num;
  99         __u64 avail;
 100         __u64 used;
 101 } __packed;
 102
 103 struct virtio_feature_desc {
 104         __le32 features;
 105         __u8 index;
 106 } __packed;
 107
 108 struct virtio_thinint_area {
 109         unsigned long summary_indicator;
 110         unsigned long indicator;
 111         u64 bit_nr;
 112         u8 isc;
 113 } __packed;
 114
 115 struct virtio_rev_info {
 116         __u16 revision;
 117         __u16 length;
 118         __u8 data[];
 119 };
 120
 121 /* the highest virtio-ccw revision we support */
 122 #define VIRTIO_CCW_REV_MAX 2
 123
 124 struct virtio_ccw_vq_info {
 125         struct virtqueue *vq;
 126         int num;
 127         union {
 128                 struct vq_info_block s;
 129                 struct vq_info_block_legacy l;
 130         } *info_block;
 131         int bit_nr;
 132         struct list_head node;
 133         long cookie;
 134 };
 135
 136 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 137
 138 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 139 #define MAX_AIRQ_AREAS 20
 140
 141 static int virtio_ccw_use_airq = 1;
 142
 143 struct airq_info {
 144         rwlock_t lock;
 145         u8 summary_indicator_idx;
 146         struct airq_struct airq;
 147         struct airq_iv *aiv;
 148 };
 149 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 150 static DEFINE_MUTEX(airq_areas_lock);
 151
 152 static u8 *summary_indicators;
 153
 154 static inline u8 *get_summary_indicator(struct airq_info *info)
 155 {
 156         return summary_indicators + info->summary_indicator_idx;
 157 }
 158
 159 #define CCW_CMD_SET_VQ 0x13
 160 #define CCW_CMD_VDEV_RESET 0x33
 161 #define CCW_CMD_SET_IND 0x43
 162 #define CCW_CMD_SET_CONF_IND 0x53
 163 #define CCW_CMD_READ_FEAT 0x12
 164 #define CCW_CMD_WRITE_FEAT 0x11
 165 #define CCW_CMD_READ_CONF 0x22
 166 #define CCW_CMD_WRITE_CONF 0x21
 167 #define CCW_CMD_WRITE_STATUS 0x31
 168 #define CCW_CMD_READ_VQ_CONF 0x32
 169 #define CCW_CMD_READ_STATUS 0x72
 170 #define CCW_CMD_SET_IND_ADAPTER 0x73
 171 #define CCW_CMD_SET_VIRTIO_REV 0x83
 172
 173 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 174 #define VIRTIO_CCW_DOING_RESET 0x00040000
 175 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 176 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 177 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 178 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 179 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 180 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 181 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 182 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 183 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 184 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 185 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 186 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 187
 188 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 189 {
 190         return container_of(vdev, struct virtio_ccw_device, vdev);
 191 }
 192
 193 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 194 {
 195         unsigned long i, flags;
 196
 197         write_lock_irqsave(&info->lock, flags);
 198         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 199                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 200                         airq_iv_free_bit(info->aiv, i);
 201                         airq_iv_set_ptr(info->aiv, i, 0);
 202                         break;
 203                 }
 204         }
 205         write_unlock_irqrestore(&info->lock, flags);
 206 }
 207
 208 static void virtio_airq_handler(struct airq_struct *airq,
 209                                 struct tpi_info *tpi_info)
 210 {
 211         struct airq_info *info = container_of(airq, struct airq_info, airq);
 212         unsigned long ai;
 213
 214         inc_irq_stat(IRQIO_VAI);
 215         read_lock(&info->lock);
 216         /* Walk through indicators field, summary indicator active. */
 217         for (ai = 0;;) {
 218                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 219                 if (ai == -1UL)
 220                         break;
 221                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 222         }
 223         *(get_summary_indicator(info)) = 0;
 224         smp_wmb();
 225         /* Walk through indicators field, summary indicator not active. */
 226         for (ai = 0;;) {
 227                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 228                 if (ai == -1UL)
 229                         break;
 230                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 231         }
 232         read_unlock(&info->lock);
 233 }
 234
 235 static struct airq_info *new_airq_info(int index)
 236 {
 237         struct airq_info *info;
 238         int rc;
 239
 240         info = kzalloc(sizeof(*info), GFP_KERNEL);
 241         if (!info)
 242                 return NULL;
 243         rwlock_init(&info->lock);
 244         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 245                                    | AIRQ_IV_CACHELINE, NULL);
 246         if (!info->aiv) {
 247                 kfree(info);
 248                 return NULL;
 249         }
 250         info->airq.handler = virtio_airq_handler;
 251         info->summary_indicator_idx = index;
 252         info->airq.lsi_ptr = get_summary_indicator(info);
 253         info->airq.lsi_mask = 0xff;
 254         info->airq.isc = VIRTIO_AIRQ_ISC;
 255         rc = register_adapter_interrupt(&info->airq);
 256         if (rc) {
 257                 airq_iv_release(info->aiv);
 258                 kfree(info);
 259                 return NULL;
 260         }
 261         return info;
 262 }
 263
 264 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 265                                         u64 *first, void **airq_info)
 266 {
 267         int i, j;
 268         struct airq_info *info;
 269         unsigned long indicator_addr = 0;
 270         unsigned long bit, flags;
 271
 272         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 273                 mutex_lock(&airq_areas_lock);
 274                 if (!airq_areas[i])
 275                         airq_areas[i] = new_airq_info(i);
 276                 info = airq_areas[i];
 277                 mutex_unlock(&airq_areas_lock);
 278                 if (!info)
 279                         return 0;
 280                 write_lock_irqsave(&info->lock, flags);
 281                 bit = airq_iv_alloc(info->aiv, nvqs);
 282                 if (bit == -1UL) {
 283                         /* Not enough vacancies. */
 284                         write_unlock_irqrestore(&info->lock, flags);
 285                         continue;
 286                 }
 287                 *first = bit;
 288                 *airq_info = info;
 289                 indicator_addr = (unsigned long)info->aiv->vector;
 290                 for (j = 0; j < nvqs; j++) {
 291                         airq_iv_set_ptr(info->aiv, bit + j,
 292                                         (unsigned long)vqs[j]);
 293                 }
 294                 write_unlock_irqrestore(&info->lock, flags);
 295         }
 296         return indicator_addr;
 297 }
 298
 299 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 300 {
 301         struct virtio_ccw_vq_info *info;
 302
 303         if (!vcdev->airq_info)
 304                 return;
 305         list_for_each_entry(info, &vcdev->virtqueues, node)
 306                 drop_airq_indicator(info->vq, vcdev->airq_info);
 307 }
 308
 309 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 310 {
 311         unsigned long flags;
 312         __u32 ret;
 313
 314         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 315         if (vcdev->err)
 316                 ret = 0;
 317         else
 318                 ret = vcdev->curr_io & flag;
 319         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 320         return ret;
 321 }
 322
 323 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 324                          struct ccw1 *ccw, __u32 intparm)
 325 {
 326         int ret;
 327         unsigned long flags;
 328         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 329
 330         mutex_lock(&vcdev->io_lock);
 331         do {
 332                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 333                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 334                 if (!ret) {
 335                         if (!vcdev->curr_io)
 336                                 vcdev->err = 0;
 337                         vcdev->curr_io |= flag;
 338                 }
 339                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 340                 cpu_relax();
 341         } while (ret == -EBUSY);
 342         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 343         ret = ret ? ret : vcdev->err;
 344         mutex_unlock(&vcdev->io_lock);
 345         return ret;
 346 }
 347
 348 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 349                                       struct ccw1 *ccw)
 350 {
 351         int ret;
 352         unsigned long *indicatorp = NULL;
 353         struct virtio_thinint_area *thinint_area = NULL;
 354         struct airq_info *airq_info = vcdev->airq_info;
 355
 356         if (vcdev->is_thinint) {
 357                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 358                                                      sizeof(*thinint_area));
 359                 if (!thinint_area)
 360                         return;
 361                 thinint_area->summary_indicator =
 362                         (unsigned long) get_summary_indicator(airq_info);
 363                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 364                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 365                 ccw->count = sizeof(*thinint_area);
 366                 ccw->cda = (__u32)(unsigned long) thinint_area;
 367         } else {
 368                 /* payload is the address of the indicators */
 369                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 370                                                    sizeof(indicators(vcdev)));
 371                 if (!indicatorp)
 372                         return;
 373                 *indicatorp = 0;
 374                 ccw->cmd_code = CCW_CMD_SET_IND;
 375                 ccw->count = sizeof(indicators(vcdev));
 376                 ccw->cda = (__u32)(unsigned long) indicatorp;
 377         }
 378         /* Deregister indicators from host. */
 379         *indicators(vcdev) = 0;
 380         ccw->flags = 0;
 381         ret = ccw_io_helper(vcdev, ccw,
 382                             vcdev->is_thinint ?
 383                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 384                             VIRTIO_CCW_DOING_SET_IND);
 385         if (ret && (ret != -ENODEV))
 386                 dev_info(&vcdev->cdev->dev,
 387                          "Failed to deregister indicators (%d)\n", ret);
 388         else if (vcdev->is_thinint)
 389                 virtio_ccw_drop_indicators(vcdev);
 390         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
 391         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 392 }
 393
 394 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 395 {
 396         struct virtio_ccw_vq_info *info = vq->priv;
 397         struct virtio_ccw_device *vcdev;
 398         struct subchannel_id schid;
 399
 400         vcdev = to_vc_device(info->vq->vdev);
 401         ccw_device_get_schid(vcdev->cdev, &schid);
 402         BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
 403         info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
 404                                       *((unsigned int *)&schid),
 405                                       vq->index, info->cookie);
 406         if (info->cookie < 0)
 407                 return false;
 408         return true;
 409 }
 410
 411 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 412                                    struct ccw1 *ccw, int index)
 413 {
 414         int ret;
 415
 416         vcdev->dma_area->config_block.index = index;
 417         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 418         ccw->flags = 0;
 419         ccw->count = sizeof(struct vq_config_block);
 420         ccw->cda = (__u32)(unsigned long)(&vcdev->dma_area->config_block);
 421         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 422         if (ret)
 423                 return ret;
 424         return vcdev->dma_area->config_block.num ?: -ENOENT;
 425 }
 426
 427 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 428 {
 429         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 430         struct virtio_ccw_vq_info *info = vq->priv;
 431         unsigned long flags;
 432         int ret;
 433         unsigned int index = vq->index;
 434
 435         /* Remove from our list. */
 436         spin_lock_irqsave(&vcdev->lock, flags);
 437         list_del(&info->node);
 438         spin_unlock_irqrestore(&vcdev->lock, flags);
 439
 440         /* Release from host. */
 441         if (vcdev->revision == 0) {
 442                 info->info_block->l.queue = 0;
 443                 info->info_block->l.align = 0;
 444                 info->info_block->l.index = index;
 445                 info->info_block->l.num = 0;
 446                 ccw->count = sizeof(info->info_block->l);
 447         } else {
 448                 info->info_block->s.desc = 0;
 449                 info->info_block->s.index = index;
 450                 info->info_block->s.num = 0;
 451                 info->info_block->s.avail = 0;
 452                 info->info_block->s.used = 0;
 453                 ccw->count = sizeof(info->info_block->s);
 454         }
 455         ccw->cmd_code = CCW_CMD_SET_VQ;
 456         ccw->flags = 0;
 457         ccw->cda = (__u32)(unsigned long)(info->info_block);
 458         ret = ccw_io_helper(vcdev, ccw,
 459                             VIRTIO_CCW_DOING_SET_VQ | index);
 460         /*
 461          * -ENODEV isn't considered an error: The device is gone anyway.
 462          * This may happen on device detach.
 463          */
 464         if (ret && (ret != -ENODEV))
 465                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 466                          ret, index);
 467
 468         vring_del_virtqueue(vq);
 469         ccw_device_dma_free(vcdev->cdev, info->info_block,
 470                             sizeof(*info->info_block));
 471         kfree(info);
 472 }
 473
 474 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 475 {
 476         struct virtqueue *vq, *n;
 477         struct ccw1 *ccw;
 478         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 479
 480         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 481         if (!ccw)
 482                 return;
 483
 484         virtio_ccw_drop_indicator(vcdev, ccw);
 485
 486         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 487                 virtio_ccw_del_vq(vq, ccw);
 488
 489         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 490 }
 491
 492 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 493                                              int i, vq_callback_t *callback,
 494                                              const char *name, bool ctx,
 495                                              struct ccw1 *ccw)
 496 {
 497         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 498         int err;
 499         struct virtqueue *vq = NULL;
 500         struct virtio_ccw_vq_info *info;
 501         u64 queue;
 502         unsigned long flags;
 503         bool may_reduce;
 504
 505         /* Allocate queue. */
 506         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 507         if (!info) {
 508                 dev_warn(&vcdev->cdev->dev, "no info\n");
 509                 err = -ENOMEM;
 510                 goto out_err;
 511         }
 512         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 513                                                  sizeof(*info->info_block));
 514         if (!info->info_block) {
 515                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 516                 err = -ENOMEM;
 517                 goto out_err;
 518         }
 519         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 520         if (info->num < 0) {
 521                 err = info->num;
 522                 goto out_err;
 523         }
 524         may_reduce = vcdev->revision > 0;
 525         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 526                                     vdev, true, may_reduce, ctx,
 527                                     virtio_ccw_kvm_notify, callback, name);
 528
 529         if (!vq) {
 530                 /* For now, we fail if we can't get the requested size. */
 531                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 532                 err = -ENOMEM;
 533                 goto out_err;
 534         }
 535         /* it may have been reduced */
 536         info->num = virtqueue_get_vring_size(vq);
 537
 538         /* Register it with the host. */
 539         queue = virtqueue_get_desc_addr(vq);
 540         if (vcdev->revision == 0) {
 541                 info->info_block->l.queue = queue;
 542                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 543                 info->info_block->l.index = i;
 544                 info->info_block->l.num = info->num;
 545                 ccw->count = sizeof(info->info_block->l);
 546         } else {
 547                 info->info_block->s.desc = queue;
 548                 info->info_block->s.index = i;
 549                 info->info_block->s.num = info->num;
 550                 info->info_block->s.avail = (__u64)virtqueue_get_avail_addr(vq);
 551                 info->info_block->s.used = (__u64)virtqueue_get_used_addr(vq);
 552                 ccw->count = sizeof(info->info_block->s);
 553         }
 554         ccw->cmd_code = CCW_CMD_SET_VQ;
 555         ccw->flags = 0;
 556         ccw->cda = (__u32)(unsigned long)(info->info_block);
 557         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 558         if (err) {
 559                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 560                 goto out_err;
 561         }
 562
 563         info->vq = vq;
 564         vq->priv = info;
 565
 566         /* Save it to our list. */
 567         spin_lock_irqsave(&vcdev->lock, flags);
 568         list_add(&info->node, &vcdev->virtqueues);
 569         spin_unlock_irqrestore(&vcdev->lock, flags);
 570
 571         return vq;
 572
 573 out_err:
 574         if (vq)
 575                 vring_del_virtqueue(vq);
 576         if (info) {
 577                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 578                                     sizeof(*info->info_block));
 579         }
 580         kfree(info);
 581         return ERR_PTR(err);
 582 }
 583
 584 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 585                                            struct virtqueue *vqs[], int nvqs,
 586                                            struct ccw1 *ccw)
 587 {
 588         int ret;
 589         struct virtio_thinint_area *thinint_area = NULL;
 590         struct airq_info *info;
 591
 592         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 593                                              sizeof(*thinint_area));
 594         if (!thinint_area) {
 595                 ret = -ENOMEM;
 596                 goto out;
 597         }
 598         /* Try to get an indicator. */
 599         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 600                                                      &thinint_area->bit_nr,
 601                                                      &vcdev->airq_info);
 602         if (!thinint_area->indicator) {
 603                 ret = -ENOSPC;
 604                 goto out;
 605         }
 606         info = vcdev->airq_info;
 607         thinint_area->summary_indicator =
 608                 (unsigned long) get_summary_indicator(info);
 609         thinint_area->isc = VIRTIO_AIRQ_ISC;
 610         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 611         ccw->flags = CCW_FLAG_SLI;
 612         ccw->count = sizeof(*thinint_area);
 613         ccw->cda = (__u32)(unsigned long)thinint_area;
 614         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 615         if (ret) {
 616                 if (ret == -EOPNOTSUPP) {
 617                         /*
 618                          * The host does not support adapter interrupts
 619                          * for virtio-ccw, stop trying.
 620                          */
 621                         virtio_ccw_use_airq = 0;
 622                         pr_info("Adapter interrupts unsupported on host\n");
 623                 } else
 624                         dev_warn(&vcdev->cdev->dev,
 625                                  "enabling adapter interrupts = %d\n", ret);
 626                 virtio_ccw_drop_indicators(vcdev);
 627         }
 628 out:
 629         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 630         return ret;
 631 }
 632
 633 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 634                                struct virtqueue *vqs[],
 635                                vq_callback_t *callbacks[],
 636                                const char * const names[],
 637                                const bool *ctx,
 638                                struct irq_affinity *desc)
 639 {
 640         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 641         unsigned long *indicatorp = NULL;
 642         int ret, i, queue_idx = 0;
 643         struct ccw1 *ccw;
 644
 645         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 646         if (!ccw)
 647                 return -ENOMEM;
 648
 649         for (i = 0; i < nvqs; ++i) {
 650                 if (!names[i]) {
 651                         vqs[i] = NULL;
 652                         continue;
 653                 }
 654
 655                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 656                                              names[i], ctx ? ctx[i] : false,
 657                                              ccw);
 658                 if (IS_ERR(vqs[i])) {
 659                         ret = PTR_ERR(vqs[i]);
 660                         vqs[i] = NULL;
 661                         goto out;
 662                 }
 663         }
 664         ret = -ENOMEM;
 665         /*
 666          * We need a data area under 2G to communicate. Our payload is
 667          * the address of the indicators.
 668         */
 669         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 670                                            sizeof(indicators(vcdev)));
 671         if (!indicatorp)
 672                 goto out;
 673         *indicatorp = (unsigned long) indicators(vcdev);
 674         if (vcdev->is_thinint) {
 675                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 676                 if (ret)
 677                         /* no error, just fall back to legacy interrupts */
 678                         vcdev->is_thinint = false;
 679         }
 680         if (!vcdev->is_thinint) {
 681                 /* Register queue indicators with host. */
 682                 *indicators(vcdev) = 0;
 683                 ccw->cmd_code = CCW_CMD_SET_IND;
 684                 ccw->flags = 0;
 685                 ccw->count = sizeof(indicators(vcdev));
 686                 ccw->cda = (__u32)(unsigned long) indicatorp;
 687                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 688                 if (ret)
 689                         goto out;
 690         }
 691         /* Register indicators2 with host for config changes */
 692         *indicatorp = (unsigned long) indicators2(vcdev);
 693         *indicators2(vcdev) = 0;
 694         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 695         ccw->flags = 0;
 696         ccw->count = sizeof(indicators2(vcdev));
 697         ccw->cda = (__u32)(unsigned long) indicatorp;
 698         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 699         if (ret)
 700                 goto out;
 701
 702         if (indicatorp)
 703                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 704                                     sizeof(indicators(vcdev)));
 705         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 706         return 0;
 707 out:
 708         if (indicatorp)
 709                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 710                                     sizeof(indicators(vcdev)));
 711         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 712         virtio_ccw_del_vqs(vdev);
 713         return ret;
 714 }
 715
 716 static void virtio_ccw_reset(struct virtio_device *vdev)
 717 {
 718         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 719         struct ccw1 *ccw;
 720
 721         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 722         if (!ccw)
 723                 return;
 724
 725         /* Zero status bits. */
 726         vcdev->dma_area->status = 0;
 727
 728         /* Send a reset ccw on device. */
 729         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 730         ccw->flags = 0;
 731         ccw->count = 0;
 732         ccw->cda = 0;
 733         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 734         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 735 }
 736
 737 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 738 {
 739         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 740         struct virtio_feature_desc *features;
 741         int ret;
 742         u64 rc;
 743         struct ccw1 *ccw;
 744
 745         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 746         if (!ccw)
 747                 return 0;
 748
 749         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 750         if (!features) {
 751                 rc = 0;
 752                 goto out_free;
 753         }
 754         /* Read the feature bits from the host. */
 755         features->index = 0;
 756         ccw->cmd_code = CCW_CMD_READ_FEAT;
 757         ccw->flags = 0;
 758         ccw->count = sizeof(*features);
 759         ccw->cda = (__u32)(unsigned long)features;
 760         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 761         if (ret) {
 762                 rc = 0;
 763                 goto out_free;
 764         }
 765
 766         rc = le32_to_cpu(features->features);
 767
 768         if (vcdev->revision == 0)
 769                 goto out_free;
 770
 771         /* Read second half of the feature bits from the host. */
 772         features->index = 1;
 773         ccw->cmd_code = CCW_CMD_READ_FEAT;
 774         ccw->flags = 0;
 775         ccw->count = sizeof(*features);
 776         ccw->cda = (__u32)(unsigned long)features;
 777         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 778         if (ret == 0)
 779                 rc |= (u64)le32_to_cpu(features->features) << 32;
 780
 781 out_free:
 782         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 783         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 784         return rc;
 785 }
 786
 787 static void ccw_transport_features(struct virtio_device *vdev)
 788 {
 789         /*
 790          * Currently nothing to do here.
 791          */
 792 }
 793
 794 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 795 {
 796         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 797         struct virtio_feature_desc *features;
 798         struct ccw1 *ccw;
 799         int ret;
 800
 801         if (vcdev->revision >= 1 &&
 802             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 803                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 804                         "but does not have VIRTIO_F_VERSION_1\n");
 805                 return -EINVAL;
 806         }
 807
 808         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 809         if (!ccw)
 810                 return -ENOMEM;
 811
 812         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 813         if (!features) {
 814                 ret = -ENOMEM;
 815                 goto out_free;
 816         }
 817         /* Give virtio_ring a chance to accept features. */
 818         vring_transport_features(vdev);
 819
 820         /* Give virtio_ccw a chance to accept features. */
 821         ccw_transport_features(vdev);
 822
 823         features->index = 0;
 824         features->features = cpu_to_le32((u32)vdev->features);
 825         /* Write the first half of the feature bits to the host. */
 826         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 827         ccw->flags = 0;
 828         ccw->count = sizeof(*features);
 829         ccw->cda = (__u32)(unsigned long)features;
 830         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 831         if (ret)
 832                 goto out_free;
 833
 834         if (vcdev->revision == 0)
 835                 goto out_free;
 836
 837         features->index = 1;
 838         features->features = cpu_to_le32(vdev->features >> 32);
 839         /* Write the second half of the feature bits to the host. */
 840         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 841         ccw->flags = 0;
 842         ccw->count = sizeof(*features);
 843         ccw->cda = (__u32)(unsigned long)features;
 844         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 845
 846 out_free:
 847         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 848         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 849
 850         return ret;
 851 }
 852
 853 static void virtio_ccw_get_config(struct virtio_device *vdev,
 854                                   unsigned int offset, void *buf, unsigned len)
 855 {
 856         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 857         int ret;
 858         struct ccw1 *ccw;
 859         void *config_area;
 860         unsigned long flags;
 861
 862         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 863         if (!ccw)
 864                 return;
 865
 866         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 867                                             VIRTIO_CCW_CONFIG_SIZE);
 868         if (!config_area)
 869                 goto out_free;
 870
 871         /* Read the config area from the host. */
 872         ccw->cmd_code = CCW_CMD_READ_CONF;
 873         ccw->flags = 0;
 874         ccw->count = offset + len;
 875         ccw->cda = (__u32)(unsigned long)config_area;
 876         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 877         if (ret)
 878                 goto out_free;
 879
 880         spin_lock_irqsave(&vcdev->lock, flags);
 881         memcpy(vcdev->config, config_area, offset + len);
 882         if (vcdev->config_ready < offset + len)
 883                 vcdev->config_ready = offset + len;
 884         spin_unlock_irqrestore(&vcdev->lock, flags);
 885         if (buf)
 886                 memcpy(buf, config_area + offset, len);
 887
 888 out_free:
 889         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 890         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 891 }
 892
 893 static void virtio_ccw_set_config(struct virtio_device *vdev,
 894                                   unsigned int offset, const void *buf,
 895                                   unsigned len)
 896 {
 897         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 898         struct ccw1 *ccw;
 899         void *config_area;
 900         unsigned long flags;
 901
 902         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 903         if (!ccw)
 904                 return;
 905
 906         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 907                                             VIRTIO_CCW_CONFIG_SIZE);
 908         if (!config_area)
 909                 goto out_free;
 910
 911         /* Make sure we don't overwrite fields. */
 912         if (vcdev->config_ready < offset)
 913                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 914         spin_lock_irqsave(&vcdev->lock, flags);
 915         memcpy(&vcdev->config[offset], buf, len);
 916         /* Write the config area to the host. */
 917         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 918         spin_unlock_irqrestore(&vcdev->lock, flags);
 919         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 920         ccw->flags = 0;
 921         ccw->count = offset + len;
 922         ccw->cda = (__u32)(unsigned long)config_area;
 923         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 924
 925 out_free:
 926         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 927         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 928 }
 929
 930 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 931 {
 932         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 933         u8 old_status = vcdev->dma_area->status;
 934         struct ccw1 *ccw;
 935
 936         if (vcdev->revision < 2)
 937                 return vcdev->dma_area->status;
 938
 939         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 940         if (!ccw)
 941                 return old_status;
 942
 943         ccw->cmd_code = CCW_CMD_READ_STATUS;
 944         ccw->flags = 0;
 945         ccw->count = sizeof(vcdev->dma_area->status);
 946         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 947         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 948 /*
 949  * If the channel program failed (should only happen if the device
 950  * was hotunplugged, and then we clean up via the machine check
 951  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 952  * return the old status, which is fine.
 953 */
 954         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 955
 956         return vcdev->dma_area->status;
 957 }
 958
 959 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 960 {
 961         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 962         u8 old_status = vcdev->dma_area->status;
 963         struct ccw1 *ccw;
 964         int ret;
 965
 966         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 967         if (!ccw)
 968                 return;
 969
 970         /* Write the status to the host. */
 971         vcdev->dma_area->status = status;
 972         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 973         ccw->flags = 0;
 974         ccw->count = sizeof(status);
 975         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 976         /* We use ssch for setting the status which is a serializing
 977          * instruction that guarantees the memory writes have
 978          * completed before ssch.
 979          */
 980         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 981         /* Write failed? We assume status is unchanged. */
 982         if (ret)
 983                 vcdev->dma_area->status = old_status;
 984         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 985 }
 986
 987 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 988 {
 989         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 990
 991         return dev_name(&vcdev->cdev->dev);
 992 }
 993
 994 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
 995 {
 996         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 997         struct airq_info *info = vcdev->airq_info;
 998
 999         if (info) {
1000                 /*
1001                  * This device uses adapter interrupts: synchronize with
1002                  * vring_interrupt() called by virtio_airq_handler()
1003                  * via the indicator area lock.
1004                  */
1005                 write_lock_irq(&info->lock);
1006                 write_unlock_irq(&info->lock);
1007         } else {
1008                 /* This device uses classic interrupts: synchronize
1009                  * with vring_interrupt() called by
1010                  * virtio_ccw_int_handler() via the per-device
1011                  * irq_lock
1012                  */
1013                 write_lock_irq(&vcdev->irq_lock);
1014                 write_unlock_irq(&vcdev->irq_lock);
1015         }
1016 }
1017
1018 static const struct virtio_config_ops virtio_ccw_config_ops = {
1019         .get_features = virtio_ccw_get_features,
1020         .finalize_features = virtio_ccw_finalize_features,
1021         .get = virtio_ccw_get_config,
1022         .set = virtio_ccw_set_config,
1023         .get_status = virtio_ccw_get_status,
1024         .set_status = virtio_ccw_set_status,
1025         .reset = virtio_ccw_reset,
1026         .find_vqs = virtio_ccw_find_vqs,
1027         .del_vqs = virtio_ccw_del_vqs,
1028         .bus_name = virtio_ccw_bus_name,
1029         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1030 };
1031
1032
1033 /*
1034  * ccw bus driver related functions
1035  */
1036
1037 static void virtio_ccw_release_dev(struct device *_d)
1038 {
1039         struct virtio_device *dev = dev_to_virtio(_d);
1040         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1041
1042         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1043                             sizeof(*vcdev->dma_area));
1044         kfree(vcdev);
1045 }
1046
1047 static int irb_is_error(struct irb *irb)
1048 {
1049         if (scsw_cstat(&irb->scsw) != 0)
1050                 return 1;
1051         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1052                 return 1;
1053         if (scsw_cc(&irb->scsw) != 0)
1054                 return 1;
1055         return 0;
1056 }
1057
1058 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1059                                               int index)
1060 {
1061         struct virtio_ccw_vq_info *info;
1062         unsigned long flags;
1063         struct virtqueue *vq;
1064
1065         vq = NULL;
1066         spin_lock_irqsave(&vcdev->lock, flags);
1067         list_for_each_entry(info, &vcdev->virtqueues, node) {
1068                 if (info->vq->index == index) {
1069                         vq = info->vq;
1070                         break;
1071                 }
1072         }
1073         spin_unlock_irqrestore(&vcdev->lock, flags);
1074         return vq;
1075 }
1076
1077 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1078                                       __u32 activity)
1079 {
1080         if (vcdev->curr_io & activity) {
1081                 switch (activity) {
1082                 case VIRTIO_CCW_DOING_READ_FEAT:
1083                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1084                 case VIRTIO_CCW_DOING_READ_CONFIG:
1085                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1086                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1087                 case VIRTIO_CCW_DOING_READ_STATUS:
1088                 case VIRTIO_CCW_DOING_SET_VQ:
1089                 case VIRTIO_CCW_DOING_SET_IND:
1090                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1091                 case VIRTIO_CCW_DOING_RESET:
1092                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1093                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1094                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1095                         vcdev->curr_io &= ~activity;
1096                         wake_up(&vcdev->wait_q);
1097                         break;
1098                 default:
1099                         /* don't know what to do... */
1100                         dev_warn(&vcdev->cdev->dev,
1101                                  "Suspicious activity '%08x'\n", activity);
1102                         WARN_ON(1);
1103                         break;
1104                 }
1105         }
1106 }
1107
1108 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1109                                    unsigned long intparm,
1110                                    struct irb *irb)
1111 {
1112         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1113         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1114         int i;
1115         struct virtqueue *vq;
1116
1117         if (!vcdev)
1118                 return;
1119         if (IS_ERR(irb)) {
1120                 vcdev->err = PTR_ERR(irb);
1121                 virtio_ccw_check_activity(vcdev, activity);
1122                 /* Don't poke around indicators, something's wrong. */
1123                 return;
1124         }
1125         /* Check if it's a notification from the host. */
1126         if ((intparm == 0) &&
1127             (scsw_stctl(&irb->scsw) ==
1128              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1129                 /* OK */
1130         }
1131         if (irb_is_error(irb)) {
1132                 /* Command reject? */
1133                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1134                     (irb->ecw[0] & SNS0_CMD_REJECT))
1135                         vcdev->err = -EOPNOTSUPP;
1136                 else
1137                         /* Map everything else to -EIO. */
1138                         vcdev->err = -EIO;
1139         }
1140         virtio_ccw_check_activity(vcdev, activity);
1141 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1142         /*
1143          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1144          * disabled here.
1145          */
1146         read_lock(&vcdev->irq_lock);
1147 #endif
1148         for_each_set_bit(i, indicators(vcdev),
1149                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1150                 /* The bit clear must happen before the vring kick. */
1151                 clear_bit(i, indicators(vcdev));
1152                 barrier();
1153                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1154                 vring_interrupt(0, vq);
1155         }
1156 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1157         read_unlock(&vcdev->irq_lock);
1158 #endif
1159         if (test_bit(0, indicators2(vcdev))) {
1160                 virtio_config_changed(&vcdev->vdev);
1161                 clear_bit(0, indicators2(vcdev));
1162         }
1163 }
1164
1165 /*
1166  * We usually want to autoonline all devices, but give the admin
1167  * a way to exempt devices from this.
1168  */
1169 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1170                      (8*sizeof(long)))
1171 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1172
1173 static char *no_auto = "";
1174
1175 module_param(no_auto, charp, 0444);
1176 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1177
1178 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1179 {
1180         struct ccw_dev_id id;
1181
1182         ccw_device_get_id(cdev, &id);
1183         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1184                 return 0;
1185         return 1;
1186 }
1187
1188 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1189 {
1190         struct ccw_device *cdev = data;
1191         int ret;
1192
1193         ret = ccw_device_set_online(cdev);
1194         if (ret)
1195                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1196 }
1197
1198 static int virtio_ccw_probe(struct ccw_device *cdev)
1199 {
1200         cdev->handler = virtio_ccw_int_handler;
1201
1202         if (virtio_ccw_check_autoonline(cdev))
1203                 async_schedule(virtio_ccw_auto_online, cdev);
1204         return 0;
1205 }
1206
1207 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1208 {
1209         unsigned long flags;
1210         struct virtio_ccw_device *vcdev;
1211
1212         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1213         vcdev = dev_get_drvdata(&cdev->dev);
1214         if (!vcdev || vcdev->going_away) {
1215                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1216                 return NULL;
1217         }
1218         vcdev->going_away = true;
1219         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1220         return vcdev;
1221 }
1222
1223 static void virtio_ccw_remove(struct ccw_device *cdev)
1224 {
1225         unsigned long flags;
1226         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1227
1228         if (vcdev && cdev->online) {
1229                 if (vcdev->device_lost)
1230                         virtio_break_device(&vcdev->vdev);
1231                 unregister_virtio_device(&vcdev->vdev);
1232                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1233                 dev_set_drvdata(&cdev->dev, NULL);
1234                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1235         }
1236         cdev->handler = NULL;
1237 }
1238
1239 static int virtio_ccw_offline(struct ccw_device *cdev)
1240 {
1241         unsigned long flags;
1242         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1243
1244         if (!vcdev)
1245                 return 0;
1246         if (vcdev->device_lost)
1247                 virtio_break_device(&vcdev->vdev);
1248         unregister_virtio_device(&vcdev->vdev);
1249         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1250         dev_set_drvdata(&cdev->dev, NULL);
1251         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1252         return 0;
1253 }
1254
1255 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1256 {
1257         struct virtio_rev_info *rev;
1258         struct ccw1 *ccw;
1259         int ret;
1260
1261         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1262         if (!ccw)
1263                 return -ENOMEM;
1264         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1265         if (!rev) {
1266                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1267                 return -ENOMEM;
1268         }
1269
1270         /* Set transport revision */
1271         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1272         ccw->flags = 0;
1273         ccw->count = sizeof(*rev);
1274         ccw->cda = (__u32)(unsigned long)rev;
1275
1276         vcdev->revision = VIRTIO_CCW_REV_MAX;
1277         do {
1278                 rev->revision = vcdev->revision;
1279                 /* none of our supported revisions carry payload */
1280                 rev->length = 0;
1281                 ret = ccw_io_helper(vcdev, ccw,
1282                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1283                 if (ret == -EOPNOTSUPP) {
1284                         if (vcdev->revision == 0)
1285                                 /*
1286                                  * The host device does not support setting
1287                                  * the revision: let's operate it in legacy
1288                                  * mode.
1289                                  */
1290                                 ret = 0;
1291                         else
1292                                 vcdev->revision--;
1293                 }
1294         } while (ret == -EOPNOTSUPP);
1295
1296         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1297         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1298         return ret;
1299 }
1300
1301 static int virtio_ccw_online(struct ccw_device *cdev)
1302 {
1303         int ret;
1304         struct virtio_ccw_device *vcdev;
1305         unsigned long flags;
1306
1307         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1308         if (!vcdev) {
1309                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1310                 ret = -ENOMEM;
1311                 goto out_free;
1312         }
1313         vcdev->vdev.dev.parent = &cdev->dev;
1314         vcdev->cdev = cdev;
1315         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1316                                                 sizeof(*vcdev->dma_area));
1317         if (!vcdev->dma_area) {
1318                 ret = -ENOMEM;
1319                 goto out_free;
1320         }
1321
1322         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1323
1324         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1325         vcdev->vdev.config = &virtio_ccw_config_ops;
1326         init_waitqueue_head(&vcdev->wait_q);
1327         INIT_LIST_HEAD(&vcdev->virtqueues);
1328         spin_lock_init(&vcdev->lock);
1329         rwlock_init(&vcdev->irq_lock);
1330         mutex_init(&vcdev->io_lock);
1331
1332         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1333         dev_set_drvdata(&cdev->dev, vcdev);
1334         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1335         vcdev->vdev.id.vendor = cdev->id.cu_type;
1336         vcdev->vdev.id.device = cdev->id.cu_model;
1337
1338         ret = virtio_ccw_set_transport_rev(vcdev);
1339         if (ret)
1340                 goto out_free;
1341
1342         ret = register_virtio_device(&vcdev->vdev);
1343         if (ret) {
1344                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1345                          ret);
1346                 goto out_put;
1347         }
1348         return 0;
1349 out_put:
1350         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1351         dev_set_drvdata(&cdev->dev, NULL);
1352         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1353         put_device(&vcdev->vdev.dev);
1354         return ret;
1355 out_free:
1356         if (vcdev) {
1357                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1358                                     sizeof(*vcdev->dma_area));
1359         }
1360         kfree(vcdev);
1361         return ret;
1362 }
1363
1364 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1365 {
1366         int rc;
1367         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1368
1369         /*
1370          * Make sure vcdev is set
1371          * i.e. set_offline/remove callback not already running
1372          */
1373         if (!vcdev)
1374                 return NOTIFY_DONE;
1375
1376         switch (event) {
1377         case CIO_GONE:
1378                 vcdev->device_lost = true;
1379                 rc = NOTIFY_DONE;
1380                 break;
1381         case CIO_OPER:
1382                 rc = NOTIFY_OK;
1383                 break;
1384         default:
1385                 rc = NOTIFY_DONE;
1386                 break;
1387         }
1388         return rc;
1389 }
1390
1391 static struct ccw_device_id virtio_ids[] = {
1392         { CCW_DEVICE(0x3832, 0) },
1393         {},
1394 };
1395
1396 static struct ccw_driver virtio_ccw_driver = {
1397         .driver = {
1398                 .owner = THIS_MODULE,
1399                 .name = "virtio_ccw",
1400         },
1401         .ids = virtio_ids,
1402         .probe = virtio_ccw_probe,
1403         .remove = virtio_ccw_remove,
1404         .set_offline = virtio_ccw_offline,
1405         .set_online = virtio_ccw_online,
1406         .notify = virtio_ccw_cio_notify,
1407         .int_class = IRQIO_VIR,
1408 };
1409
1410 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1411                            int max_digit, int max_val)
1412 {
1413         int diff;
1414
1415         diff = 0;
1416         *val = 0;
1417
1418         while (diff <= max_digit) {
1419                 int value = hex_to_bin(**cp);
1420
1421                 if (value < 0)
1422                         break;
1423                 *val = *val * 16 + value;
1424                 (*cp)++;
1425                 diff++;
1426         }
1427
1428         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1429                 return 1;
1430
1431         return 0;
1432 }
1433
1434 static int __init parse_busid(char *str, unsigned int *cssid,
1435                               unsigned int *ssid, unsigned int *devno)
1436 {
1437         char *str_work;
1438         int rc, ret;
1439
1440         rc = 1;
1441
1442         if (*str == '\0')
1443                 goto out;
1444
1445         str_work = str;
1446         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1447         if (ret || (str_work[0] != '.'))
1448                 goto out;
1449         str_work++;
1450         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1451         if (ret || (str_work[0] != '.'))
1452                 goto out;
1453         str_work++;
1454         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1455         if (ret || (str_work[0] != '\0'))
1456                 goto out;
1457
1458         rc = 0;
1459 out:
1460         return rc;
1461 }
1462
1463 static void __init no_auto_parse(void)
1464 {
1465         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1466         char *parm, *str;
1467         int rc;
1468
1469         str = no_auto;
1470         while ((parm = strsep(&str, ","))) {
1471                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1472                                  &from_ssid, &from);
1473                 if (rc)
1474                         continue;
1475                 if (parm != NULL) {
1476                         rc = parse_busid(parm, &to_cssid,
1477                                          &to_ssid, &to);
1478                         if ((from_ssid > to_ssid) ||
1479                             ((from_ssid == to_ssid) && (from > to)))
1480                                 rc = -EINVAL;
1481                 } else {
1482                         to_cssid = from_cssid;
1483                         to_ssid = from_ssid;
1484                         to = from;
1485                 }
1486                 if (rc)
1487                         continue;
1488                 while ((from_ssid < to_ssid) ||
1489                        ((from_ssid == to_ssid) && (from <= to))) {
1490                         set_bit(from, devs_no_auto[from_ssid]);
1491                         from++;
1492                         if (from > __MAX_SUBCHANNEL) {
1493                                 from_ssid++;
1494                                 from = 0;
1495                         }
1496                 }
1497         }
1498 }
1499
1500 static int __init virtio_ccw_init(void)
1501 {
1502         int rc;
1503
1504         /* parse no_auto string before we do anything further */
1505         no_auto_parse();
1506
1507         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1508         if (!summary_indicators)
1509                 return -ENOMEM;
1510         rc = ccw_driver_register(&virtio_ccw_driver);
1511         if (rc)
1512                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1513         return rc;
1514 }
1515 device_initcall(virtio_ccw_init);