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 };
  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
 536         vq->num_max = info->num;
 537
 538         /* it may have been reduced */
 539         info->num = virtqueue_get_vring_size(vq);
 540
 541         /* Register it with the host. */
 542         queue = virtqueue_get_desc_addr(vq);
 543         if (vcdev->revision == 0) {
 544                 info->info_block->l.queue = queue;
 545                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 546                 info->info_block->l.index = i;
 547                 info->info_block->l.num = info->num;
 548                 ccw->count = sizeof(info->info_block->l);
 549         } else {
 550                 info->info_block->s.desc = queue;
 551                 info->info_block->s.index = i;
 552                 info->info_block->s.num = info->num;
 553                 info->info_block->s.avail = (__u64)virtqueue_get_avail_addr(vq);
 554                 info->info_block->s.used = (__u64)virtqueue_get_used_addr(vq);
 555                 ccw->count = sizeof(info->info_block->s);
 556         }
 557         ccw->cmd_code = CCW_CMD_SET_VQ;
 558         ccw->flags = 0;
 559         ccw->cda = (__u32)(unsigned long)(info->info_block);
 560         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 561         if (err) {
 562                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 563                 goto out_err;
 564         }
 565
 566         info->vq = vq;
 567         vq->priv = info;
 568
 569         /* Save it to our list. */
 570         spin_lock_irqsave(&vcdev->lock, flags);
 571         list_add(&info->node, &vcdev->virtqueues);
 572         spin_unlock_irqrestore(&vcdev->lock, flags);
 573
 574         return vq;
 575
 576 out_err:
 577         if (vq)
 578                 vring_del_virtqueue(vq);
 579         if (info) {
 580                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 581                                     sizeof(*info->info_block));
 582         }
 583         kfree(info);
 584         return ERR_PTR(err);
 585 }
 586
 587 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 588                                            struct virtqueue *vqs[], int nvqs,
 589                                            struct ccw1 *ccw)
 590 {
 591         int ret;
 592         struct virtio_thinint_area *thinint_area = NULL;
 593         struct airq_info *info;
 594
 595         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 596                                              sizeof(*thinint_area));
 597         if (!thinint_area) {
 598                 ret = -ENOMEM;
 599                 goto out;
 600         }
 601         /* Try to get an indicator. */
 602         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 603                                                      &thinint_area->bit_nr,
 604                                                      &vcdev->airq_info);
 605         if (!thinint_area->indicator) {
 606                 ret = -ENOSPC;
 607                 goto out;
 608         }
 609         info = vcdev->airq_info;
 610         thinint_area->summary_indicator =
 611                 (unsigned long) get_summary_indicator(info);
 612         thinint_area->isc = VIRTIO_AIRQ_ISC;
 613         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 614         ccw->flags = CCW_FLAG_SLI;
 615         ccw->count = sizeof(*thinint_area);
 616         ccw->cda = (__u32)(unsigned long)thinint_area;
 617         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 618         if (ret) {
 619                 if (ret == -EOPNOTSUPP) {
 620                         /*
 621                          * The host does not support adapter interrupts
 622                          * for virtio-ccw, stop trying.
 623                          */
 624                         virtio_ccw_use_airq = 0;
 625                         pr_info("Adapter interrupts unsupported on host\n");
 626                 } else
 627                         dev_warn(&vcdev->cdev->dev,
 628                                  "enabling adapter interrupts = %d\n", ret);
 629                 virtio_ccw_drop_indicators(vcdev);
 630         }
 631 out:
 632         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 633         return ret;
 634 }
 635
 636 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 637                                struct virtqueue *vqs[],
 638                                vq_callback_t *callbacks[],
 639                                const char * const names[],
 640                                const bool *ctx,
 641                                struct irq_affinity *desc)
 642 {
 643         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 644         unsigned long *indicatorp = NULL;
 645         int ret, i, queue_idx = 0;
 646         struct ccw1 *ccw;
 647
 648         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 649         if (!ccw)
 650                 return -ENOMEM;
 651
 652         for (i = 0; i < nvqs; ++i) {
 653                 if (!names[i]) {
 654                         vqs[i] = NULL;
 655                         continue;
 656                 }
 657
 658                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 659                                              names[i], ctx ? ctx[i] : false,
 660                                              ccw);
 661                 if (IS_ERR(vqs[i])) {
 662                         ret = PTR_ERR(vqs[i]);
 663                         vqs[i] = NULL;
 664                         goto out;
 665                 }
 666         }
 667         ret = -ENOMEM;
 668         /*
 669          * We need a data area under 2G to communicate. Our payload is
 670          * the address of the indicators.
 671         */
 672         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 673                                            sizeof(indicators(vcdev)));
 674         if (!indicatorp)
 675                 goto out;
 676         *indicatorp = (unsigned long) indicators(vcdev);
 677         if (vcdev->is_thinint) {
 678                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 679                 if (ret)
 680                         /* no error, just fall back to legacy interrupts */
 681                         vcdev->is_thinint = false;
 682         }
 683         if (!vcdev->is_thinint) {
 684                 /* Register queue indicators with host. */
 685                 *indicators(vcdev) = 0;
 686                 ccw->cmd_code = CCW_CMD_SET_IND;
 687                 ccw->flags = 0;
 688                 ccw->count = sizeof(indicators(vcdev));
 689                 ccw->cda = (__u32)(unsigned long) indicatorp;
 690                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 691                 if (ret)
 692                         goto out;
 693         }
 694         /* Register indicators2 with host for config changes */
 695         *indicatorp = (unsigned long) indicators2(vcdev);
 696         *indicators2(vcdev) = 0;
 697         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 698         ccw->flags = 0;
 699         ccw->count = sizeof(indicators2(vcdev));
 700         ccw->cda = (__u32)(unsigned long) indicatorp;
 701         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 702         if (ret)
 703                 goto out;
 704
 705         if (indicatorp)
 706                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 707                                     sizeof(indicators(vcdev)));
 708         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 709         return 0;
 710 out:
 711         if (indicatorp)
 712                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 713                                     sizeof(indicators(vcdev)));
 714         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 715         virtio_ccw_del_vqs(vdev);
 716         return ret;
 717 }
 718
 719 static void virtio_ccw_reset(struct virtio_device *vdev)
 720 {
 721         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 722         struct ccw1 *ccw;
 723
 724         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 725         if (!ccw)
 726                 return;
 727
 728         /* Zero status bits. */
 729         vcdev->dma_area->status = 0;
 730
 731         /* Send a reset ccw on device. */
 732         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 733         ccw->flags = 0;
 734         ccw->count = 0;
 735         ccw->cda = 0;
 736         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 737         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 738 }
 739
 740 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 741 {
 742         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 743         struct virtio_feature_desc *features;
 744         int ret;
 745         u64 rc;
 746         struct ccw1 *ccw;
 747
 748         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 749         if (!ccw)
 750                 return 0;
 751
 752         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 753         if (!features) {
 754                 rc = 0;
 755                 goto out_free;
 756         }
 757         /* Read the feature bits from the host. */
 758         features->index = 0;
 759         ccw->cmd_code = CCW_CMD_READ_FEAT;
 760         ccw->flags = 0;
 761         ccw->count = sizeof(*features);
 762         ccw->cda = (__u32)(unsigned long)features;
 763         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 764         if (ret) {
 765                 rc = 0;
 766                 goto out_free;
 767         }
 768
 769         rc = le32_to_cpu(features->features);
 770
 771         if (vcdev->revision == 0)
 772                 goto out_free;
 773
 774         /* Read second half of the feature bits from the host. */
 775         features->index = 1;
 776         ccw->cmd_code = CCW_CMD_READ_FEAT;
 777         ccw->flags = 0;
 778         ccw->count = sizeof(*features);
 779         ccw->cda = (__u32)(unsigned long)features;
 780         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 781         if (ret == 0)
 782                 rc |= (u64)le32_to_cpu(features->features) << 32;
 783
 784 out_free:
 785         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 786         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 787         return rc;
 788 }
 789
 790 static void ccw_transport_features(struct virtio_device *vdev)
 791 {
 792         /*
 793          * Currently nothing to do here.
 794          */
 795 }
 796
 797 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 798 {
 799         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 800         struct virtio_feature_desc *features;
 801         struct ccw1 *ccw;
 802         int ret;
 803
 804         if (vcdev->revision >= 1 &&
 805             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 806                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 807                         "but does not have VIRTIO_F_VERSION_1\n");
 808                 return -EINVAL;
 809         }
 810
 811         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 812         if (!ccw)
 813                 return -ENOMEM;
 814
 815         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 816         if (!features) {
 817                 ret = -ENOMEM;
 818                 goto out_free;
 819         }
 820         /* Give virtio_ring a chance to accept features. */
 821         vring_transport_features(vdev);
 822
 823         /* Give virtio_ccw a chance to accept features. */
 824         ccw_transport_features(vdev);
 825
 826         features->index = 0;
 827         features->features = cpu_to_le32((u32)vdev->features);
 828         /* Write the first half of the feature bits to the host. */
 829         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 830         ccw->flags = 0;
 831         ccw->count = sizeof(*features);
 832         ccw->cda = (__u32)(unsigned long)features;
 833         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 834         if (ret)
 835                 goto out_free;
 836
 837         if (vcdev->revision == 0)
 838                 goto out_free;
 839
 840         features->index = 1;
 841         features->features = cpu_to_le32(vdev->features >> 32);
 842         /* Write the second half of the feature bits to the host. */
 843         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 844         ccw->flags = 0;
 845         ccw->count = sizeof(*features);
 846         ccw->cda = (__u32)(unsigned long)features;
 847         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 848
 849 out_free:
 850         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 851         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 852
 853         return ret;
 854 }
 855
 856 static void virtio_ccw_get_config(struct virtio_device *vdev,
 857                                   unsigned int offset, void *buf, unsigned len)
 858 {
 859         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 860         int ret;
 861         struct ccw1 *ccw;
 862         void *config_area;
 863         unsigned long flags;
 864
 865         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 866         if (!ccw)
 867                 return;
 868
 869         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 870                                             VIRTIO_CCW_CONFIG_SIZE);
 871         if (!config_area)
 872                 goto out_free;
 873
 874         /* Read the config area from the host. */
 875         ccw->cmd_code = CCW_CMD_READ_CONF;
 876         ccw->flags = 0;
 877         ccw->count = offset + len;
 878         ccw->cda = (__u32)(unsigned long)config_area;
 879         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 880         if (ret)
 881                 goto out_free;
 882
 883         spin_lock_irqsave(&vcdev->lock, flags);
 884         memcpy(vcdev->config, config_area, offset + len);
 885         if (vcdev->config_ready < offset + len)
 886                 vcdev->config_ready = offset + len;
 887         spin_unlock_irqrestore(&vcdev->lock, flags);
 888         if (buf)
 889                 memcpy(buf, config_area + offset, len);
 890
 891 out_free:
 892         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 893         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 894 }
 895
 896 static void virtio_ccw_set_config(struct virtio_device *vdev,
 897                                   unsigned int offset, const void *buf,
 898                                   unsigned len)
 899 {
 900         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 901         struct ccw1 *ccw;
 902         void *config_area;
 903         unsigned long flags;
 904
 905         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 906         if (!ccw)
 907                 return;
 908
 909         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 910                                             VIRTIO_CCW_CONFIG_SIZE);
 911         if (!config_area)
 912                 goto out_free;
 913
 914         /* Make sure we don't overwrite fields. */
 915         if (vcdev->config_ready < offset)
 916                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 917         spin_lock_irqsave(&vcdev->lock, flags);
 918         memcpy(&vcdev->config[offset], buf, len);
 919         /* Write the config area to the host. */
 920         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 921         spin_unlock_irqrestore(&vcdev->lock, flags);
 922         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 923         ccw->flags = 0;
 924         ccw->count = offset + len;
 925         ccw->cda = (__u32)(unsigned long)config_area;
 926         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 927
 928 out_free:
 929         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 930         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 931 }
 932
 933 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 934 {
 935         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 936         u8 old_status = vcdev->dma_area->status;
 937         struct ccw1 *ccw;
 938
 939         if (vcdev->revision < 2)
 940                 return vcdev->dma_area->status;
 941
 942         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 943         if (!ccw)
 944                 return old_status;
 945
 946         ccw->cmd_code = CCW_CMD_READ_STATUS;
 947         ccw->flags = 0;
 948         ccw->count = sizeof(vcdev->dma_area->status);
 949         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 950         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 951 /*
 952  * If the channel program failed (should only happen if the device
 953  * was hotunplugged, and then we clean up via the machine check
 954  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 955  * return the old status, which is fine.
 956 */
 957         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 958
 959         return vcdev->dma_area->status;
 960 }
 961
 962 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 963 {
 964         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 965         u8 old_status = vcdev->dma_area->status;
 966         struct ccw1 *ccw;
 967         int ret;
 968
 969         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 970         if (!ccw)
 971                 return;
 972
 973         /* Write the status to the host. */
 974         vcdev->dma_area->status = status;
 975         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 976         ccw->flags = 0;
 977         ccw->count = sizeof(status);
 978         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 979         /* We use ssch for setting the status which is a serializing
 980          * instruction that guarantees the memory writes have
 981          * completed before ssch.
 982          */
 983         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 984         /* Write failed? We assume status is unchanged. */
 985         if (ret)
 986                 vcdev->dma_area->status = old_status;
 987         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 988 }
 989
 990 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 991 {
 992         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 993
 994         return dev_name(&vcdev->cdev->dev);
 995 }
 996
 997 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
 998 {
 999         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1000         struct airq_info *info = vcdev->airq_info;
1001
1002         if (info) {
1003                 /*
1004                  * This device uses adapter interrupts: synchronize with
1005                  * vring_interrupt() called by virtio_airq_handler()
1006                  * via the indicator area lock.
1007                  */
1008                 write_lock_irq(&info->lock);
1009                 write_unlock_irq(&info->lock);
1010         } else {
1011                 /* This device uses classic interrupts: synchronize
1012                  * with vring_interrupt() called by
1013                  * virtio_ccw_int_handler() via the per-device
1014                  * irq_lock
1015                  */
1016                 write_lock_irq(&vcdev->irq_lock);
1017                 write_unlock_irq(&vcdev->irq_lock);
1018         }
1019 }
1020
1021 static const struct virtio_config_ops virtio_ccw_config_ops = {
1022         .get_features = virtio_ccw_get_features,
1023         .finalize_features = virtio_ccw_finalize_features,
1024         .get = virtio_ccw_get_config,
1025         .set = virtio_ccw_set_config,
1026         .get_status = virtio_ccw_get_status,
1027         .set_status = virtio_ccw_set_status,
1028         .reset = virtio_ccw_reset,
1029         .find_vqs = virtio_ccw_find_vqs,
1030         .del_vqs = virtio_ccw_del_vqs,
1031         .bus_name = virtio_ccw_bus_name,
1032         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1033 };
1034
1035
1036 /*
1037  * ccw bus driver related functions
1038  */
1039
1040 static void virtio_ccw_release_dev(struct device *_d)
1041 {
1042         struct virtio_device *dev = dev_to_virtio(_d);
1043         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1044
1045         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1046                             sizeof(*vcdev->dma_area));
1047         kfree(vcdev);
1048 }
1049
1050 static int irb_is_error(struct irb *irb)
1051 {
1052         if (scsw_cstat(&irb->scsw) != 0)
1053                 return 1;
1054         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1055                 return 1;
1056         if (scsw_cc(&irb->scsw) != 0)
1057                 return 1;
1058         return 0;
1059 }
1060
1061 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1062                                               int index)
1063 {
1064         struct virtio_ccw_vq_info *info;
1065         unsigned long flags;
1066         struct virtqueue *vq;
1067
1068         vq = NULL;
1069         spin_lock_irqsave(&vcdev->lock, flags);
1070         list_for_each_entry(info, &vcdev->virtqueues, node) {
1071                 if (info->vq->index == index) {
1072                         vq = info->vq;
1073                         break;
1074                 }
1075         }
1076         spin_unlock_irqrestore(&vcdev->lock, flags);
1077         return vq;
1078 }
1079
1080 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1081                                       __u32 activity)
1082 {
1083         if (vcdev->curr_io & activity) {
1084                 switch (activity) {
1085                 case VIRTIO_CCW_DOING_READ_FEAT:
1086                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1087                 case VIRTIO_CCW_DOING_READ_CONFIG:
1088                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1089                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1090                 case VIRTIO_CCW_DOING_READ_STATUS:
1091                 case VIRTIO_CCW_DOING_SET_VQ:
1092                 case VIRTIO_CCW_DOING_SET_IND:
1093                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1094                 case VIRTIO_CCW_DOING_RESET:
1095                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1096                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1097                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1098                         vcdev->curr_io &= ~activity;
1099                         wake_up(&vcdev->wait_q);
1100                         break;
1101                 default:
1102                         /* don't know what to do... */
1103                         dev_warn(&vcdev->cdev->dev,
1104                                  "Suspicious activity '%08x'\n", activity);
1105                         WARN_ON(1);
1106                         break;
1107                 }
1108         }
1109 }
1110
1111 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1112                                    unsigned long intparm,
1113                                    struct irb *irb)
1114 {
1115         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1116         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1117         int i;
1118         struct virtqueue *vq;
1119
1120         if (!vcdev)
1121                 return;
1122         if (IS_ERR(irb)) {
1123                 vcdev->err = PTR_ERR(irb);
1124                 virtio_ccw_check_activity(vcdev, activity);
1125                 /* Don't poke around indicators, something's wrong. */
1126                 return;
1127         }
1128         /* Check if it's a notification from the host. */
1129         if ((intparm == 0) &&
1130             (scsw_stctl(&irb->scsw) ==
1131              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1132                 /* OK */
1133         }
1134         if (irb_is_error(irb)) {
1135                 /* Command reject? */
1136                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1137                     (irb->ecw[0] & SNS0_CMD_REJECT))
1138                         vcdev->err = -EOPNOTSUPP;
1139                 else
1140                         /* Map everything else to -EIO. */
1141                         vcdev->err = -EIO;
1142         }
1143         virtio_ccw_check_activity(vcdev, activity);
1144 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1145         /*
1146          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1147          * disabled here.
1148          */
1149         read_lock(&vcdev->irq_lock);
1150 #endif
1151         for_each_set_bit(i, indicators(vcdev),
1152                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1153                 /* The bit clear must happen before the vring kick. */
1154                 clear_bit(i, indicators(vcdev));
1155                 barrier();
1156                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1157                 vring_interrupt(0, vq);
1158         }
1159 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1160         read_unlock(&vcdev->irq_lock);
1161 #endif
1162         if (test_bit(0, indicators2(vcdev))) {
1163                 virtio_config_changed(&vcdev->vdev);
1164                 clear_bit(0, indicators2(vcdev));
1165         }
1166 }
1167
1168 /*
1169  * We usually want to autoonline all devices, but give the admin
1170  * a way to exempt devices from this.
1171  */
1172 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1173                      (8*sizeof(long)))
1174 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1175
1176 static char *no_auto = "";
1177
1178 module_param(no_auto, charp, 0444);
1179 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1180
1181 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1182 {
1183         struct ccw_dev_id id;
1184
1185         ccw_device_get_id(cdev, &id);
1186         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1187                 return 0;
1188         return 1;
1189 }
1190
1191 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1192 {
1193         struct ccw_device *cdev = data;
1194         int ret;
1195
1196         ret = ccw_device_set_online(cdev);
1197         if (ret)
1198                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1199 }
1200
1201 static int virtio_ccw_probe(struct ccw_device *cdev)
1202 {
1203         cdev->handler = virtio_ccw_int_handler;
1204
1205         if (virtio_ccw_check_autoonline(cdev))
1206                 async_schedule(virtio_ccw_auto_online, cdev);
1207         return 0;
1208 }
1209
1210 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1211 {
1212         unsigned long flags;
1213         struct virtio_ccw_device *vcdev;
1214
1215         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1216         vcdev = dev_get_drvdata(&cdev->dev);
1217         if (!vcdev || vcdev->going_away) {
1218                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1219                 return NULL;
1220         }
1221         vcdev->going_away = true;
1222         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1223         return vcdev;
1224 }
1225
1226 static void virtio_ccw_remove(struct ccw_device *cdev)
1227 {
1228         unsigned long flags;
1229         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1230
1231         if (vcdev && cdev->online) {
1232                 if (vcdev->device_lost)
1233                         virtio_break_device(&vcdev->vdev);
1234                 unregister_virtio_device(&vcdev->vdev);
1235                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1236                 dev_set_drvdata(&cdev->dev, NULL);
1237                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1238         }
1239         cdev->handler = NULL;
1240 }
1241
1242 static int virtio_ccw_offline(struct ccw_device *cdev)
1243 {
1244         unsigned long flags;
1245         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1246
1247         if (!vcdev)
1248                 return 0;
1249         if (vcdev->device_lost)
1250                 virtio_break_device(&vcdev->vdev);
1251         unregister_virtio_device(&vcdev->vdev);
1252         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1253         dev_set_drvdata(&cdev->dev, NULL);
1254         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1255         return 0;
1256 }
1257
1258 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1259 {
1260         struct virtio_rev_info *rev;
1261         struct ccw1 *ccw;
1262         int ret;
1263
1264         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1265         if (!ccw)
1266                 return -ENOMEM;
1267         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1268         if (!rev) {
1269                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1270                 return -ENOMEM;
1271         }
1272
1273         /* Set transport revision */
1274         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1275         ccw->flags = 0;
1276         ccw->count = sizeof(*rev);
1277         ccw->cda = (__u32)(unsigned long)rev;
1278
1279         vcdev->revision = VIRTIO_CCW_REV_MAX;
1280         do {
1281                 rev->revision = vcdev->revision;
1282                 /* none of our supported revisions carry payload */
1283                 rev->length = 0;
1284                 ret = ccw_io_helper(vcdev, ccw,
1285                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1286                 if (ret == -EOPNOTSUPP) {
1287                         if (vcdev->revision == 0)
1288                                 /*
1289                                  * The host device does not support setting
1290                                  * the revision: let's operate it in legacy
1291                                  * mode.
1292                                  */
1293                                 ret = 0;
1294                         else
1295                                 vcdev->revision--;
1296                 }
1297         } while (ret == -EOPNOTSUPP);
1298
1299         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1300         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1301         return ret;
1302 }
1303
1304 static int virtio_ccw_online(struct ccw_device *cdev)
1305 {
1306         int ret;
1307         struct virtio_ccw_device *vcdev;
1308         unsigned long flags;
1309
1310         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1311         if (!vcdev) {
1312                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1313                 ret = -ENOMEM;
1314                 goto out_free;
1315         }
1316         vcdev->vdev.dev.parent = &cdev->dev;
1317         vcdev->cdev = cdev;
1318         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1319                                                 sizeof(*vcdev->dma_area));
1320         if (!vcdev->dma_area) {
1321                 ret = -ENOMEM;
1322                 goto out_free;
1323         }
1324
1325         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1326
1327         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1328         vcdev->vdev.config = &virtio_ccw_config_ops;
1329         init_waitqueue_head(&vcdev->wait_q);
1330         INIT_LIST_HEAD(&vcdev->virtqueues);
1331         spin_lock_init(&vcdev->lock);
1332         rwlock_init(&vcdev->irq_lock);
1333         mutex_init(&vcdev->io_lock);
1334
1335         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1336         dev_set_drvdata(&cdev->dev, vcdev);
1337         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1338         vcdev->vdev.id.vendor = cdev->id.cu_type;
1339         vcdev->vdev.id.device = cdev->id.cu_model;
1340
1341         ret = virtio_ccw_set_transport_rev(vcdev);
1342         if (ret)
1343                 goto out_free;
1344
1345         ret = register_virtio_device(&vcdev->vdev);
1346         if (ret) {
1347                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1348                          ret);
1349                 goto out_put;
1350         }
1351         return 0;
1352 out_put:
1353         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1354         dev_set_drvdata(&cdev->dev, NULL);
1355         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1356         put_device(&vcdev->vdev.dev);
1357         return ret;
1358 out_free:
1359         if (vcdev) {
1360                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1361                                     sizeof(*vcdev->dma_area));
1362         }
1363         kfree(vcdev);
1364         return ret;
1365 }
1366
1367 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1368 {
1369         int rc;
1370         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1371
1372         /*
1373          * Make sure vcdev is set
1374          * i.e. set_offline/remove callback not already running
1375          */
1376         if (!vcdev)
1377                 return NOTIFY_DONE;
1378
1379         switch (event) {
1380         case CIO_GONE:
1381                 vcdev->device_lost = true;
1382                 rc = NOTIFY_DONE;
1383                 break;
1384         case CIO_OPER:
1385                 rc = NOTIFY_OK;
1386                 break;
1387         default:
1388                 rc = NOTIFY_DONE;
1389                 break;
1390         }
1391         return rc;
1392 }
1393
1394 static struct ccw_device_id virtio_ids[] = {
1395         { CCW_DEVICE(0x3832, 0) },
1396         {},
1397 };
1398
1399 static struct ccw_driver virtio_ccw_driver = {
1400         .driver = {
1401                 .owner = THIS_MODULE,
1402                 .name = "virtio_ccw",
1403         },
1404         .ids = virtio_ids,
1405         .probe = virtio_ccw_probe,
1406         .remove = virtio_ccw_remove,
1407         .set_offline = virtio_ccw_offline,
1408         .set_online = virtio_ccw_online,
1409         .notify = virtio_ccw_cio_notify,
1410         .int_class = IRQIO_VIR,
1411 };
1412
1413 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1414                            int max_digit, int max_val)
1415 {
1416         int diff;
1417
1418         diff = 0;
1419         *val = 0;
1420
1421         while (diff <= max_digit) {
1422                 int value = hex_to_bin(**cp);
1423
1424                 if (value < 0)
1425                         break;
1426                 *val = *val * 16 + value;
1427                 (*cp)++;
1428                 diff++;
1429         }
1430
1431         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1432                 return 1;
1433
1434         return 0;
1435 }
1436
1437 static int __init parse_busid(char *str, unsigned int *cssid,
1438                               unsigned int *ssid, unsigned int *devno)
1439 {
1440         char *str_work;
1441         int rc, ret;
1442
1443         rc = 1;
1444
1445         if (*str == '\0')
1446                 goto out;
1447
1448         str_work = str;
1449         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1450         if (ret || (str_work[0] != '.'))
1451                 goto out;
1452         str_work++;
1453         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1454         if (ret || (str_work[0] != '.'))
1455                 goto out;
1456         str_work++;
1457         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1458         if (ret || (str_work[0] != '\0'))
1459                 goto out;
1460
1461         rc = 0;
1462 out:
1463         return rc;
1464 }
1465
1466 static void __init no_auto_parse(void)
1467 {
1468         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1469         char *parm, *str;
1470         int rc;
1471
1472         str = no_auto;
1473         while ((parm = strsep(&str, ","))) {
1474                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1475                                  &from_ssid, &from);
1476                 if (rc)
1477                         continue;
1478                 if (parm != NULL) {
1479                         rc = parse_busid(parm, &to_cssid,
1480                                          &to_ssid, &to);
1481                         if ((from_ssid > to_ssid) ||
1482                             ((from_ssid == to_ssid) && (from > to)))
1483                                 rc = -EINVAL;
1484                 } else {
1485                         to_cssid = from_cssid;
1486                         to_ssid = from_ssid;
1487                         to = from;
1488                 }
1489                 if (rc)
1490                         continue;
1491                 while ((from_ssid < to_ssid) ||
1492                        ((from_ssid == to_ssid) && (from <= to))) {
1493                         set_bit(from, devs_no_auto[from_ssid]);
1494                         from++;
1495                         if (from > __MAX_SUBCHANNEL) {
1496                                 from_ssid++;
1497                                 from = 0;
1498                         }
1499                 }
1500         }
1501 }
1502
1503 static int __init virtio_ccw_init(void)
1504 {
1505         int rc;
1506
1507         /* parse no_auto string before we do anything further */
1508         no_auto_parse();
1509
1510         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1511         if (!summary_indicators)
1512                 return -ENOMEM;
1513         rc = ccw_driver_register(&virtio_ccw_driver);
1514         if (rc)
1515                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1516         return rc;
1517 }
1518 device_initcall(virtio_ccw_init);