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                                u32 sizes[],
 641                                const bool *ctx,
 642                                struct irq_affinity *desc)
 643 {
 644         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 645         unsigned long *indicatorp = NULL;
 646         int ret, i, queue_idx = 0;
 647         struct ccw1 *ccw;
 648
 649         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 650         if (!ccw)
 651                 return -ENOMEM;
 652
 653         for (i = 0; i < nvqs; ++i) {
 654                 if (!names[i]) {
 655                         vqs[i] = NULL;
 656                         continue;
 657                 }
 658
 659                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 660                                              names[i], ctx ? ctx[i] : false,
 661                                              ccw);
 662                 if (IS_ERR(vqs[i])) {
 663                         ret = PTR_ERR(vqs[i]);
 664                         vqs[i] = NULL;
 665                         goto out;
 666                 }
 667         }
 668         ret = -ENOMEM;
 669         /*
 670          * We need a data area under 2G to communicate. Our payload is
 671          * the address of the indicators.
 672         */
 673         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 674                                            sizeof(indicators(vcdev)));
 675         if (!indicatorp)
 676                 goto out;
 677         *indicatorp = (unsigned long) indicators(vcdev);
 678         if (vcdev->is_thinint) {
 679                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 680                 if (ret)
 681                         /* no error, just fall back to legacy interrupts */
 682                         vcdev->is_thinint = false;
 683         }
 684         if (!vcdev->is_thinint) {
 685                 /* Register queue indicators with host. */
 686                 *indicators(vcdev) = 0;
 687                 ccw->cmd_code = CCW_CMD_SET_IND;
 688                 ccw->flags = 0;
 689                 ccw->count = sizeof(indicators(vcdev));
 690                 ccw->cda = (__u32)(unsigned long) indicatorp;
 691                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 692                 if (ret)
 693                         goto out;
 694         }
 695         /* Register indicators2 with host for config changes */
 696         *indicatorp = (unsigned long) indicators2(vcdev);
 697         *indicators2(vcdev) = 0;
 698         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 699         ccw->flags = 0;
 700         ccw->count = sizeof(indicators2(vcdev));
 701         ccw->cda = (__u32)(unsigned long) indicatorp;
 702         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 703         if (ret)
 704                 goto out;
 705
 706         if (indicatorp)
 707                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 708                                     sizeof(indicators(vcdev)));
 709         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 710         return 0;
 711 out:
 712         if (indicatorp)
 713                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 714                                     sizeof(indicators(vcdev)));
 715         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 716         virtio_ccw_del_vqs(vdev);
 717         return ret;
 718 }
 719
 720 static void virtio_ccw_reset(struct virtio_device *vdev)
 721 {
 722         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 723         struct ccw1 *ccw;
 724
 725         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 726         if (!ccw)
 727                 return;
 728
 729         /* Zero status bits. */
 730         vcdev->dma_area->status = 0;
 731
 732         /* Send a reset ccw on device. */
 733         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 734         ccw->flags = 0;
 735         ccw->count = 0;
 736         ccw->cda = 0;
 737         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 738         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 739 }
 740
 741 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 742 {
 743         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 744         struct virtio_feature_desc *features;
 745         int ret;
 746         u64 rc;
 747         struct ccw1 *ccw;
 748
 749         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 750         if (!ccw)
 751                 return 0;
 752
 753         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 754         if (!features) {
 755                 rc = 0;
 756                 goto out_free;
 757         }
 758         /* Read the feature bits from the host. */
 759         features->index = 0;
 760         ccw->cmd_code = CCW_CMD_READ_FEAT;
 761         ccw->flags = 0;
 762         ccw->count = sizeof(*features);
 763         ccw->cda = (__u32)(unsigned long)features;
 764         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 765         if (ret) {
 766                 rc = 0;
 767                 goto out_free;
 768         }
 769
 770         rc = le32_to_cpu(features->features);
 771
 772         if (vcdev->revision == 0)
 773                 goto out_free;
 774
 775         /* Read second half of the feature bits from the host. */
 776         features->index = 1;
 777         ccw->cmd_code = CCW_CMD_READ_FEAT;
 778         ccw->flags = 0;
 779         ccw->count = sizeof(*features);
 780         ccw->cda = (__u32)(unsigned long)features;
 781         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 782         if (ret == 0)
 783                 rc |= (u64)le32_to_cpu(features->features) << 32;
 784
 785 out_free:
 786         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 787         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 788         return rc;
 789 }
 790
 791 static void ccw_transport_features(struct virtio_device *vdev)
 792 {
 793         /*
 794          * Currently nothing to do here.
 795          */
 796 }
 797
 798 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 799 {
 800         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 801         struct virtio_feature_desc *features;
 802         struct ccw1 *ccw;
 803         int ret;
 804
 805         if (vcdev->revision >= 1 &&
 806             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 807                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 808                         "but does not have VIRTIO_F_VERSION_1\n");
 809                 return -EINVAL;
 810         }
 811
 812         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 813         if (!ccw)
 814                 return -ENOMEM;
 815
 816         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 817         if (!features) {
 818                 ret = -ENOMEM;
 819                 goto out_free;
 820         }
 821         /* Give virtio_ring a chance to accept features. */
 822         vring_transport_features(vdev);
 823
 824         /* Give virtio_ccw a chance to accept features. */
 825         ccw_transport_features(vdev);
 826
 827         features->index = 0;
 828         features->features = cpu_to_le32((u32)vdev->features);
 829         /* Write the first half of the feature bits to the host. */
 830         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 831         ccw->flags = 0;
 832         ccw->count = sizeof(*features);
 833         ccw->cda = (__u32)(unsigned long)features;
 834         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 835         if (ret)
 836                 goto out_free;
 837
 838         if (vcdev->revision == 0)
 839                 goto out_free;
 840
 841         features->index = 1;
 842         features->features = cpu_to_le32(vdev->features >> 32);
 843         /* Write the second half of the feature bits to the host. */
 844         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 845         ccw->flags = 0;
 846         ccw->count = sizeof(*features);
 847         ccw->cda = (__u32)(unsigned long)features;
 848         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 849
 850 out_free:
 851         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 852         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 853
 854         return ret;
 855 }
 856
 857 static void virtio_ccw_get_config(struct virtio_device *vdev,
 858                                   unsigned int offset, void *buf, unsigned len)
 859 {
 860         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 861         int ret;
 862         struct ccw1 *ccw;
 863         void *config_area;
 864         unsigned long flags;
 865
 866         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 867         if (!ccw)
 868                 return;
 869
 870         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 871                                             VIRTIO_CCW_CONFIG_SIZE);
 872         if (!config_area)
 873                 goto out_free;
 874
 875         /* Read the config area from the host. */
 876         ccw->cmd_code = CCW_CMD_READ_CONF;
 877         ccw->flags = 0;
 878         ccw->count = offset + len;
 879         ccw->cda = (__u32)(unsigned long)config_area;
 880         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 881         if (ret)
 882                 goto out_free;
 883
 884         spin_lock_irqsave(&vcdev->lock, flags);
 885         memcpy(vcdev->config, config_area, offset + len);
 886         if (vcdev->config_ready < offset + len)
 887                 vcdev->config_ready = offset + len;
 888         spin_unlock_irqrestore(&vcdev->lock, flags);
 889         if (buf)
 890                 memcpy(buf, config_area + offset, len);
 891
 892 out_free:
 893         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 894         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 895 }
 896
 897 static void virtio_ccw_set_config(struct virtio_device *vdev,
 898                                   unsigned int offset, const void *buf,
 899                                   unsigned len)
 900 {
 901         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 902         struct ccw1 *ccw;
 903         void *config_area;
 904         unsigned long flags;
 905
 906         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 907         if (!ccw)
 908                 return;
 909
 910         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 911                                             VIRTIO_CCW_CONFIG_SIZE);
 912         if (!config_area)
 913                 goto out_free;
 914
 915         /* Make sure we don't overwrite fields. */
 916         if (vcdev->config_ready < offset)
 917                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 918         spin_lock_irqsave(&vcdev->lock, flags);
 919         memcpy(&vcdev->config[offset], buf, len);
 920         /* Write the config area to the host. */
 921         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 922         spin_unlock_irqrestore(&vcdev->lock, flags);
 923         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 924         ccw->flags = 0;
 925         ccw->count = offset + len;
 926         ccw->cda = (__u32)(unsigned long)config_area;
 927         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 928
 929 out_free:
 930         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 931         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 932 }
 933
 934 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 935 {
 936         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 937         u8 old_status = vcdev->dma_area->status;
 938         struct ccw1 *ccw;
 939
 940         if (vcdev->revision < 2)
 941                 return vcdev->dma_area->status;
 942
 943         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 944         if (!ccw)
 945                 return old_status;
 946
 947         ccw->cmd_code = CCW_CMD_READ_STATUS;
 948         ccw->flags = 0;
 949         ccw->count = sizeof(vcdev->dma_area->status);
 950         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 951         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 952 /*
 953  * If the channel program failed (should only happen if the device
 954  * was hotunplugged, and then we clean up via the machine check
 955  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 956  * return the old status, which is fine.
 957 */
 958         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 959
 960         return vcdev->dma_area->status;
 961 }
 962
 963 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 964 {
 965         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 966         u8 old_status = vcdev->dma_area->status;
 967         struct ccw1 *ccw;
 968         int ret;
 969
 970         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 971         if (!ccw)
 972                 return;
 973
 974         /* Write the status to the host. */
 975         vcdev->dma_area->status = status;
 976         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 977         ccw->flags = 0;
 978         ccw->count = sizeof(status);
 979         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 980         /* We use ssch for setting the status which is a serializing
 981          * instruction that guarantees the memory writes have
 982          * completed before ssch.
 983          */
 984         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 985         /* Write failed? We assume status is unchanged. */
 986         if (ret)
 987                 vcdev->dma_area->status = old_status;
 988         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 989 }
 990
 991 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 992 {
 993         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 994
 995         return dev_name(&vcdev->cdev->dev);
 996 }
 997
 998 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
 999 {
1000         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1001         struct airq_info *info = vcdev->airq_info;
1002
1003         if (info) {
1004                 /*
1005                  * This device uses adapter interrupts: synchronize with
1006                  * vring_interrupt() called by virtio_airq_handler()
1007                  * via the indicator area lock.
1008                  */
1009                 write_lock_irq(&info->lock);
1010                 write_unlock_irq(&info->lock);
1011         } else {
1012                 /* This device uses classic interrupts: synchronize
1013                  * with vring_interrupt() called by
1014                  * virtio_ccw_int_handler() via the per-device
1015                  * irq_lock
1016                  */
1017                 write_lock_irq(&vcdev->irq_lock);
1018                 write_unlock_irq(&vcdev->irq_lock);
1019         }
1020 }
1021
1022 static const struct virtio_config_ops virtio_ccw_config_ops = {
1023         .get_features = virtio_ccw_get_features,
1024         .finalize_features = virtio_ccw_finalize_features,
1025         .get = virtio_ccw_get_config,
1026         .set = virtio_ccw_set_config,
1027         .get_status = virtio_ccw_get_status,
1028         .set_status = virtio_ccw_set_status,
1029         .reset = virtio_ccw_reset,
1030         .find_vqs = virtio_ccw_find_vqs,
1031         .del_vqs = virtio_ccw_del_vqs,
1032         .bus_name = virtio_ccw_bus_name,
1033         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1034 };
1035
1036
1037 /*
1038  * ccw bus driver related functions
1039  */
1040
1041 static void virtio_ccw_release_dev(struct device *_d)
1042 {
1043         struct virtio_device *dev = dev_to_virtio(_d);
1044         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1045
1046         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1047                             sizeof(*vcdev->dma_area));
1048         kfree(vcdev);
1049 }
1050
1051 static int irb_is_error(struct irb *irb)
1052 {
1053         if (scsw_cstat(&irb->scsw) != 0)
1054                 return 1;
1055         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1056                 return 1;
1057         if (scsw_cc(&irb->scsw) != 0)
1058                 return 1;
1059         return 0;
1060 }
1061
1062 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1063                                               int index)
1064 {
1065         struct virtio_ccw_vq_info *info;
1066         unsigned long flags;
1067         struct virtqueue *vq;
1068
1069         vq = NULL;
1070         spin_lock_irqsave(&vcdev->lock, flags);
1071         list_for_each_entry(info, &vcdev->virtqueues, node) {
1072                 if (info->vq->index == index) {
1073                         vq = info->vq;
1074                         break;
1075                 }
1076         }
1077         spin_unlock_irqrestore(&vcdev->lock, flags);
1078         return vq;
1079 }
1080
1081 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1082                                       __u32 activity)
1083 {
1084         if (vcdev->curr_io & activity) {
1085                 switch (activity) {
1086                 case VIRTIO_CCW_DOING_READ_FEAT:
1087                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1088                 case VIRTIO_CCW_DOING_READ_CONFIG:
1089                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1090                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1091                 case VIRTIO_CCW_DOING_READ_STATUS:
1092                 case VIRTIO_CCW_DOING_SET_VQ:
1093                 case VIRTIO_CCW_DOING_SET_IND:
1094                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1095                 case VIRTIO_CCW_DOING_RESET:
1096                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1097                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1098                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1099                         vcdev->curr_io &= ~activity;
1100                         wake_up(&vcdev->wait_q);
1101                         break;
1102                 default:
1103                         /* don't know what to do... */
1104                         dev_warn(&vcdev->cdev->dev,
1105                                  "Suspicious activity '%08x'\n", activity);
1106                         WARN_ON(1);
1107                         break;
1108                 }
1109         }
1110 }
1111
1112 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1113                                    unsigned long intparm,
1114                                    struct irb *irb)
1115 {
1116         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1117         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1118         int i;
1119         struct virtqueue *vq;
1120
1121         if (!vcdev)
1122                 return;
1123         if (IS_ERR(irb)) {
1124                 vcdev->err = PTR_ERR(irb);
1125                 virtio_ccw_check_activity(vcdev, activity);
1126                 /* Don't poke around indicators, something's wrong. */
1127                 return;
1128         }
1129         /* Check if it's a notification from the host. */
1130         if ((intparm == 0) &&
1131             (scsw_stctl(&irb->scsw) ==
1132              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1133                 /* OK */
1134         }
1135         if (irb_is_error(irb)) {
1136                 /* Command reject? */
1137                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1138                     (irb->ecw[0] & SNS0_CMD_REJECT))
1139                         vcdev->err = -EOPNOTSUPP;
1140                 else
1141                         /* Map everything else to -EIO. */
1142                         vcdev->err = -EIO;
1143         }
1144         virtio_ccw_check_activity(vcdev, activity);
1145 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1146         /*
1147          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1148          * disabled here.
1149          */
1150         read_lock(&vcdev->irq_lock);
1151 #endif
1152         for_each_set_bit(i, indicators(vcdev),
1153                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1154                 /* The bit clear must happen before the vring kick. */
1155                 clear_bit(i, indicators(vcdev));
1156                 barrier();
1157                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1158                 vring_interrupt(0, vq);
1159         }
1160 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1161         read_unlock(&vcdev->irq_lock);
1162 #endif
1163         if (test_bit(0, indicators2(vcdev))) {
1164                 virtio_config_changed(&vcdev->vdev);
1165                 clear_bit(0, indicators2(vcdev));
1166         }
1167 }
1168
1169 /*
1170  * We usually want to autoonline all devices, but give the admin
1171  * a way to exempt devices from this.
1172  */
1173 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1174                      (8*sizeof(long)))
1175 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1176
1177 static char *no_auto = "";
1178
1179 module_param(no_auto, charp, 0444);
1180 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1181
1182 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1183 {
1184         struct ccw_dev_id id;
1185
1186         ccw_device_get_id(cdev, &id);
1187         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1188                 return 0;
1189         return 1;
1190 }
1191
1192 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1193 {
1194         struct ccw_device *cdev = data;
1195         int ret;
1196
1197         ret = ccw_device_set_online(cdev);
1198         if (ret)
1199                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1200 }
1201
1202 static int virtio_ccw_probe(struct ccw_device *cdev)
1203 {
1204         cdev->handler = virtio_ccw_int_handler;
1205
1206         if (virtio_ccw_check_autoonline(cdev))
1207                 async_schedule(virtio_ccw_auto_online, cdev);
1208         return 0;
1209 }
1210
1211 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1212 {
1213         unsigned long flags;
1214         struct virtio_ccw_device *vcdev;
1215
1216         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1217         vcdev = dev_get_drvdata(&cdev->dev);
1218         if (!vcdev || vcdev->going_away) {
1219                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1220                 return NULL;
1221         }
1222         vcdev->going_away = true;
1223         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1224         return vcdev;
1225 }
1226
1227 static void virtio_ccw_remove(struct ccw_device *cdev)
1228 {
1229         unsigned long flags;
1230         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1231
1232         if (vcdev && cdev->online) {
1233                 if (vcdev->device_lost)
1234                         virtio_break_device(&vcdev->vdev);
1235                 unregister_virtio_device(&vcdev->vdev);
1236                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1237                 dev_set_drvdata(&cdev->dev, NULL);
1238                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1239         }
1240         cdev->handler = NULL;
1241 }
1242
1243 static int virtio_ccw_offline(struct ccw_device *cdev)
1244 {
1245         unsigned long flags;
1246         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1247
1248         if (!vcdev)
1249                 return 0;
1250         if (vcdev->device_lost)
1251                 virtio_break_device(&vcdev->vdev);
1252         unregister_virtio_device(&vcdev->vdev);
1253         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1254         dev_set_drvdata(&cdev->dev, NULL);
1255         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1256         return 0;
1257 }
1258
1259 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1260 {
1261         struct virtio_rev_info *rev;
1262         struct ccw1 *ccw;
1263         int ret;
1264
1265         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1266         if (!ccw)
1267                 return -ENOMEM;
1268         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1269         if (!rev) {
1270                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1271                 return -ENOMEM;
1272         }
1273
1274         /* Set transport revision */
1275         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1276         ccw->flags = 0;
1277         ccw->count = sizeof(*rev);
1278         ccw->cda = (__u32)(unsigned long)rev;
1279
1280         vcdev->revision = VIRTIO_CCW_REV_MAX;
1281         do {
1282                 rev->revision = vcdev->revision;
1283                 /* none of our supported revisions carry payload */
1284                 rev->length = 0;
1285                 ret = ccw_io_helper(vcdev, ccw,
1286                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1287                 if (ret == -EOPNOTSUPP) {
1288                         if (vcdev->revision == 0)
1289                                 /*
1290                                  * The host device does not support setting
1291                                  * the revision: let's operate it in legacy
1292                                  * mode.
1293                                  */
1294                                 ret = 0;
1295                         else
1296                                 vcdev->revision--;
1297                 }
1298         } while (ret == -EOPNOTSUPP);
1299
1300         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1301         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1302         return ret;
1303 }
1304
1305 static int virtio_ccw_online(struct ccw_device *cdev)
1306 {
1307         int ret;
1308         struct virtio_ccw_device *vcdev;
1309         unsigned long flags;
1310
1311         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1312         if (!vcdev) {
1313                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1314                 ret = -ENOMEM;
1315                 goto out_free;
1316         }
1317         vcdev->vdev.dev.parent = &cdev->dev;
1318         vcdev->cdev = cdev;
1319         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1320                                                 sizeof(*vcdev->dma_area));
1321         if (!vcdev->dma_area) {
1322                 ret = -ENOMEM;
1323                 goto out_free;
1324         }
1325
1326         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1327
1328         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1329         vcdev->vdev.config = &virtio_ccw_config_ops;
1330         init_waitqueue_head(&vcdev->wait_q);
1331         INIT_LIST_HEAD(&vcdev->virtqueues);
1332         spin_lock_init(&vcdev->lock);
1333         rwlock_init(&vcdev->irq_lock);
1334         mutex_init(&vcdev->io_lock);
1335
1336         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1337         dev_set_drvdata(&cdev->dev, vcdev);
1338         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1339         vcdev->vdev.id.vendor = cdev->id.cu_type;
1340         vcdev->vdev.id.device = cdev->id.cu_model;
1341
1342         ret = virtio_ccw_set_transport_rev(vcdev);
1343         if (ret)
1344                 goto out_free;
1345
1346         ret = register_virtio_device(&vcdev->vdev);
1347         if (ret) {
1348                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1349                          ret);
1350                 goto out_put;
1351         }
1352         return 0;
1353 out_put:
1354         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1355         dev_set_drvdata(&cdev->dev, NULL);
1356         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1357         put_device(&vcdev->vdev.dev);
1358         return ret;
1359 out_free:
1360         if (vcdev) {
1361                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1362                                     sizeof(*vcdev->dma_area));
1363         }
1364         kfree(vcdev);
1365         return ret;
1366 }
1367
1368 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1369 {
1370         int rc;
1371         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1372
1373         /*
1374          * Make sure vcdev is set
1375          * i.e. set_offline/remove callback not already running
1376          */
1377         if (!vcdev)
1378                 return NOTIFY_DONE;
1379
1380         switch (event) {
1381         case CIO_GONE:
1382                 vcdev->device_lost = true;
1383                 rc = NOTIFY_DONE;
1384                 break;
1385         case CIO_OPER:
1386                 rc = NOTIFY_OK;
1387                 break;
1388         default:
1389                 rc = NOTIFY_DONE;
1390                 break;
1391         }
1392         return rc;
1393 }
1394
1395 static struct ccw_device_id virtio_ids[] = {
1396         { CCW_DEVICE(0x3832, 0) },
1397         {},
1398 };
1399
1400 static struct ccw_driver virtio_ccw_driver = {
1401         .driver = {
1402                 .owner = THIS_MODULE,
1403                 .name = "virtio_ccw",
1404         },
1405         .ids = virtio_ids,
1406         .probe = virtio_ccw_probe,
1407         .remove = virtio_ccw_remove,
1408         .set_offline = virtio_ccw_offline,
1409         .set_online = virtio_ccw_online,
1410         .notify = virtio_ccw_cio_notify,
1411         .int_class = IRQIO_VIR,
1412 };
1413
1414 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1415                            int max_digit, int max_val)
1416 {
1417         int diff;
1418
1419         diff = 0;
1420         *val = 0;
1421
1422         while (diff <= max_digit) {
1423                 int value = hex_to_bin(**cp);
1424
1425                 if (value < 0)
1426                         break;
1427                 *val = *val * 16 + value;
1428                 (*cp)++;
1429                 diff++;
1430         }
1431
1432         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1433                 return 1;
1434
1435         return 0;
1436 }
1437
1438 static int __init parse_busid(char *str, unsigned int *cssid,
1439                               unsigned int *ssid, unsigned int *devno)
1440 {
1441         char *str_work;
1442         int rc, ret;
1443
1444         rc = 1;
1445
1446         if (*str == '\0')
1447                 goto out;
1448
1449         str_work = str;
1450         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1451         if (ret || (str_work[0] != '.'))
1452                 goto out;
1453         str_work++;
1454         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1455         if (ret || (str_work[0] != '.'))
1456                 goto out;
1457         str_work++;
1458         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1459         if (ret || (str_work[0] != '\0'))
1460                 goto out;
1461
1462         rc = 0;
1463 out:
1464         return rc;
1465 }
1466
1467 static void __init no_auto_parse(void)
1468 {
1469         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1470         char *parm, *str;
1471         int rc;
1472
1473         str = no_auto;
1474         while ((parm = strsep(&str, ","))) {
1475                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1476                                  &from_ssid, &from);
1477                 if (rc)
1478                         continue;
1479                 if (parm != NULL) {
1480                         rc = parse_busid(parm, &to_cssid,
1481                                          &to_ssid, &to);
1482                         if ((from_ssid > to_ssid) ||
1483                             ((from_ssid == to_ssid) && (from > to)))
1484                                 rc = -EINVAL;
1485                 } else {
1486                         to_cssid = from_cssid;
1487                         to_ssid = from_ssid;
1488                         to = from;
1489                 }
1490                 if (rc)
1491                         continue;
1492                 while ((from_ssid < to_ssid) ||
1493                        ((from_ssid == to_ssid) && (from <= to))) {
1494                         set_bit(from, devs_no_auto[from_ssid]);
1495                         from++;
1496                         if (from > __MAX_SUBCHANNEL) {
1497                                 from_ssid++;
1498                                 from = 0;
1499                         }
1500                 }
1501         }
1502 }
1503
1504 static int __init virtio_ccw_init(void)
1505 {
1506         int rc;
1507
1508         /* parse no_auto string before we do anything further */
1509         no_auto_parse();
1510
1511         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1512         if (!summary_indicators)
1513                 return -ENOMEM;
1514         rc = ccw_driver_register(&virtio_ccw_driver);
1515         if (rc)
1516                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1517         return rc;
1518 }
1519 device_initcall(virtio_ccw_init);