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
  37 /*
  38  * virtio related functions
  39  */
  40
  41 struct vq_config_block {
  42         __u16 index;
  43         __u16 num;
  44 } __packed;
  45
  46 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  47 /* same as PCI config space size, should be enough for all drivers */
  48
  49 struct virtio_ccw_device {
  50         struct virtio_device vdev;
  51         __u8 *status;
  52         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  53         struct ccw_device *cdev;
  54         __u32 curr_io;
  55         int err;
  56         unsigned int revision; /* Transport revision */
  57         wait_queue_head_t wait_q;
  58         spinlock_t lock;
  59         struct mutex io_lock; /* Serializes I/O requests */
  60         struct list_head virtqueues;
  61         unsigned long indicators;
  62         unsigned long indicators2;
  63         struct vq_config_block *config_block;
  64         bool is_thinint;
  65         bool going_away;
  66         bool device_lost;
  67         unsigned int config_ready;
  68         void *airq_info;
  69 };
  70
  71 struct vq_info_block_legacy {
  72         __u64 queue;
  73         __u32 align;
  74         __u16 index;
  75         __u16 num;
  76 } __packed;
  77
  78 struct vq_info_block {
  79         __u64 desc;
  80         __u32 res0;
  81         __u16 index;
  82         __u16 num;
  83         __u64 avail;
  84         __u64 used;
  85 } __packed;
  86
  87 struct virtio_feature_desc {
  88         __le32 features;
  89         __u8 index;
  90 } __packed;
  91
  92 struct virtio_thinint_area {
  93         unsigned long summary_indicator;
  94         unsigned long indicator;
  95         u64 bit_nr;
  96         u8 isc;
  97 } __packed;
  98
  99 struct virtio_rev_info {
 100         __u16 revision;
 101         __u16 length;
 102         __u8 data[];
 103 };
 104
 105 /* the highest virtio-ccw revision we support */
 106 #define VIRTIO_CCW_REV_MAX 1
 107
 108 struct virtio_ccw_vq_info {
 109         struct virtqueue *vq;
 110         int num;
 111         void *queue;
 112         union {
 113                 struct vq_info_block s;
 114                 struct vq_info_block_legacy l;
 115         } *info_block;
 116         int bit_nr;
 117         struct list_head node;
 118         long cookie;
 119 };
 120
 121 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 122
 123 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 124 #define MAX_AIRQ_AREAS 20
 125
 126 static int virtio_ccw_use_airq = 1;
 127
 128 struct airq_info {
 129         rwlock_t lock;
 130         u8 summary_indicator;
 131         struct airq_struct airq;
 132         struct airq_iv *aiv;
 133 };
 134 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 135
 136 #define CCW_CMD_SET_VQ 0x13
 137 #define CCW_CMD_VDEV_RESET 0x33
 138 #define CCW_CMD_SET_IND 0x43
 139 #define CCW_CMD_SET_CONF_IND 0x53
 140 #define CCW_CMD_READ_FEAT 0x12
 141 #define CCW_CMD_WRITE_FEAT 0x11
 142 #define CCW_CMD_READ_CONF 0x22
 143 #define CCW_CMD_WRITE_CONF 0x21
 144 #define CCW_CMD_WRITE_STATUS 0x31
 145 #define CCW_CMD_READ_VQ_CONF 0x32
 146 #define CCW_CMD_READ_STATUS 0x72
 147 #define CCW_CMD_SET_IND_ADAPTER 0x73
 148 #define CCW_CMD_SET_VIRTIO_REV 0x83
 149
 150 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 151 #define VIRTIO_CCW_DOING_RESET 0x00040000
 152 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 153 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 154 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 155 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 156 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 157 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 158 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 159 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 160 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 161 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 162 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 163 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 164
 165 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 166 {
 167         return container_of(vdev, struct virtio_ccw_device, vdev);
 168 }
 169
 170 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 171 {
 172         unsigned long i, flags;
 173
 174         write_lock_irqsave(&info->lock, flags);
 175         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 176                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 177                         airq_iv_free_bit(info->aiv, i);
 178                         airq_iv_set_ptr(info->aiv, i, 0);
 179                         break;
 180                 }
 181         }
 182         write_unlock_irqrestore(&info->lock, flags);
 183 }
 184
 185 static void virtio_airq_handler(struct airq_struct *airq)
 186 {
 187         struct airq_info *info = container_of(airq, struct airq_info, airq);
 188         unsigned long ai;
 189
 190         inc_irq_stat(IRQIO_VAI);
 191         read_lock(&info->lock);
 192         /* Walk through indicators field, summary indicator active. */
 193         for (ai = 0;;) {
 194                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 195                 if (ai == -1UL)
 196                         break;
 197                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 198         }
 199         info->summary_indicator = 0;
 200         smp_wmb();
 201         /* Walk through indicators field, summary indicator not active. */
 202         for (ai = 0;;) {
 203                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 204                 if (ai == -1UL)
 205                         break;
 206                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 207         }
 208         read_unlock(&info->lock);
 209 }
 210
 211 static struct airq_info *new_airq_info(void)
 212 {
 213         struct airq_info *info;
 214         int rc;
 215
 216         info = kzalloc(sizeof(*info), GFP_KERNEL);
 217         if (!info)
 218                 return NULL;
 219         rwlock_init(&info->lock);
 220         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
 221         if (!info->aiv) {
 222                 kfree(info);
 223                 return NULL;
 224         }
 225         info->airq.handler = virtio_airq_handler;
 226         info->airq.lsi_ptr = &info->summary_indicator;
 227         info->airq.lsi_mask = 0xff;
 228         info->airq.isc = VIRTIO_AIRQ_ISC;
 229         rc = register_adapter_interrupt(&info->airq);
 230         if (rc) {
 231                 airq_iv_release(info->aiv);
 232                 kfree(info);
 233                 return NULL;
 234         }
 235         return info;
 236 }
 237
 238 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 239                                         u64 *first, void **airq_info)
 240 {
 241         int i, j;
 242         struct airq_info *info;
 243         unsigned long indicator_addr = 0;
 244         unsigned long bit, flags;
 245
 246         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 247                 if (!airq_areas[i])
 248                         airq_areas[i] = new_airq_info();
 249                 info = airq_areas[i];
 250                 if (!info)
 251                         return 0;
 252                 write_lock_irqsave(&info->lock, flags);
 253                 bit = airq_iv_alloc(info->aiv, nvqs);
 254                 if (bit == -1UL) {
 255                         /* Not enough vacancies. */
 256                         write_unlock_irqrestore(&info->lock, flags);
 257                         continue;
 258                 }
 259                 *first = bit;
 260                 *airq_info = info;
 261                 indicator_addr = (unsigned long)info->aiv->vector;
 262                 for (j = 0; j < nvqs; j++) {
 263                         airq_iv_set_ptr(info->aiv, bit + j,
 264                                         (unsigned long)vqs[j]);
 265                 }
 266                 write_unlock_irqrestore(&info->lock, flags);
 267         }
 268         return indicator_addr;
 269 }
 270
 271 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 272 {
 273         struct virtio_ccw_vq_info *info;
 274
 275         list_for_each_entry(info, &vcdev->virtqueues, node)
 276                 drop_airq_indicator(info->vq, vcdev->airq_info);
 277 }
 278
 279 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 280 {
 281         unsigned long flags;
 282         __u32 ret;
 283
 284         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 285         if (vcdev->err)
 286                 ret = 0;
 287         else
 288                 ret = vcdev->curr_io & flag;
 289         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 290         return ret;
 291 }
 292
 293 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 294                          struct ccw1 *ccw, __u32 intparm)
 295 {
 296         int ret;
 297         unsigned long flags;
 298         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 299
 300         mutex_lock(&vcdev->io_lock);
 301         do {
 302                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 303                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 304                 if (!ret) {
 305                         if (!vcdev->curr_io)
 306                                 vcdev->err = 0;
 307                         vcdev->curr_io |= flag;
 308                 }
 309                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 310                 cpu_relax();
 311         } while (ret == -EBUSY);
 312         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 313         ret = ret ? ret : vcdev->err;
 314         mutex_unlock(&vcdev->io_lock);
 315         return ret;
 316 }
 317
 318 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 319                                       struct ccw1 *ccw)
 320 {
 321         int ret;
 322         unsigned long *indicatorp = NULL;
 323         struct virtio_thinint_area *thinint_area = NULL;
 324         struct airq_info *airq_info = vcdev->airq_info;
 325
 326         if (vcdev->is_thinint) {
 327                 thinint_area = kzalloc(sizeof(*thinint_area),
 328                                        GFP_DMA | GFP_KERNEL);
 329                 if (!thinint_area)
 330                         return;
 331                 thinint_area->summary_indicator =
 332                         (unsigned long) &airq_info->summary_indicator;
 333                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 334                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 335                 ccw->count = sizeof(*thinint_area);
 336                 ccw->cda = (__u32)(unsigned long) thinint_area;
 337         } else {
 338                 /* payload is the address of the indicators */
 339                 indicatorp = kmalloc(sizeof(&vcdev->indicators),
 340                                      GFP_DMA | GFP_KERNEL);
 341                 if (!indicatorp)
 342                         return;
 343                 *indicatorp = 0;
 344                 ccw->cmd_code = CCW_CMD_SET_IND;
 345                 ccw->count = sizeof(&vcdev->indicators);
 346                 ccw->cda = (__u32)(unsigned long) indicatorp;
 347         }
 348         /* Deregister indicators from host. */
 349         vcdev->indicators = 0;
 350         ccw->flags = 0;
 351         ret = ccw_io_helper(vcdev, ccw,
 352                             vcdev->is_thinint ?
 353                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 354                             VIRTIO_CCW_DOING_SET_IND);
 355         if (ret && (ret != -ENODEV))
 356                 dev_info(&vcdev->cdev->dev,
 357                          "Failed to deregister indicators (%d)\n", ret);
 358         else if (vcdev->is_thinint)
 359                 virtio_ccw_drop_indicators(vcdev);
 360         kfree(indicatorp);
 361         kfree(thinint_area);
 362 }
 363
 364 static inline long __do_kvm_notify(struct subchannel_id schid,
 365                                    unsigned long queue_index,
 366                                    long cookie)
 367 {
 368         register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 369         register struct subchannel_id __schid asm("2") = schid;
 370         register unsigned long __index asm("3") = queue_index;
 371         register long __rc asm("2");
 372         register long __cookie asm("4") = cookie;
 373
 374         asm volatile ("diag 2,4,0x500\n"
 375                       : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 376                       "d"(__cookie)
 377                       : "memory", "cc");
 378         return __rc;
 379 }
 380
 381 static inline long do_kvm_notify(struct subchannel_id schid,
 382                                  unsigned long queue_index,
 383                                  long cookie)
 384 {
 385         diag_stat_inc(DIAG_STAT_X500);
 386         return __do_kvm_notify(schid, queue_index, cookie);
 387 }
 388
 389 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 390 {
 391         struct virtio_ccw_vq_info *info = vq->priv;
 392         struct virtio_ccw_device *vcdev;
 393         struct subchannel_id schid;
 394
 395         vcdev = to_vc_device(info->vq->vdev);
 396         ccw_device_get_schid(vcdev->cdev, &schid);
 397         info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 398         if (info->cookie < 0)
 399                 return false;
 400         return true;
 401 }
 402
 403 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 404                                    struct ccw1 *ccw, int index)
 405 {
 406         int ret;
 407
 408         vcdev->config_block->index = index;
 409         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 410         ccw->flags = 0;
 411         ccw->count = sizeof(struct vq_config_block);
 412         ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
 413         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 414         if (ret)
 415                 return ret;
 416         return vcdev->config_block->num;
 417 }
 418
 419 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 420 {
 421         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 422         struct virtio_ccw_vq_info *info = vq->priv;
 423         unsigned long flags;
 424         unsigned long size;
 425         int ret;
 426         unsigned int index = vq->index;
 427
 428         /* Remove from our list. */
 429         spin_lock_irqsave(&vcdev->lock, flags);
 430         list_del(&info->node);
 431         spin_unlock_irqrestore(&vcdev->lock, flags);
 432
 433         /* Release from host. */
 434         if (vcdev->revision == 0) {
 435                 info->info_block->l.queue = 0;
 436                 info->info_block->l.align = 0;
 437                 info->info_block->l.index = index;
 438                 info->info_block->l.num = 0;
 439                 ccw->count = sizeof(info->info_block->l);
 440         } else {
 441                 info->info_block->s.desc = 0;
 442                 info->info_block->s.index = index;
 443                 info->info_block->s.num = 0;
 444                 info->info_block->s.avail = 0;
 445                 info->info_block->s.used = 0;
 446                 ccw->count = sizeof(info->info_block->s);
 447         }
 448         ccw->cmd_code = CCW_CMD_SET_VQ;
 449         ccw->flags = 0;
 450         ccw->cda = (__u32)(unsigned long)(info->info_block);
 451         ret = ccw_io_helper(vcdev, ccw,
 452                             VIRTIO_CCW_DOING_SET_VQ | index);
 453         /*
 454          * -ENODEV isn't considered an error: The device is gone anyway.
 455          * This may happen on device detach.
 456          */
 457         if (ret && (ret != -ENODEV))
 458                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 459                          ret, index);
 460
 461         vring_del_virtqueue(vq);
 462         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 463         free_pages_exact(info->queue, size);
 464         kfree(info->info_block);
 465         kfree(info);
 466 }
 467
 468 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 469 {
 470         struct virtqueue *vq, *n;
 471         struct ccw1 *ccw;
 472         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 473
 474         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 475         if (!ccw)
 476                 return;
 477
 478         virtio_ccw_drop_indicator(vcdev, ccw);
 479
 480         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 481                 virtio_ccw_del_vq(vq, ccw);
 482
 483         kfree(ccw);
 484 }
 485
 486 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 487                                              int i, vq_callback_t *callback,
 488                                              const char *name, bool ctx,
 489                                              struct ccw1 *ccw)
 490 {
 491         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 492         int err;
 493         struct virtqueue *vq = NULL;
 494         struct virtio_ccw_vq_info *info;
 495         unsigned long size = 0; /* silence the compiler */
 496         unsigned long flags;
 497
 498         /* Allocate queue. */
 499         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 500         if (!info) {
 501                 dev_warn(&vcdev->cdev->dev, "no info\n");
 502                 err = -ENOMEM;
 503                 goto out_err;
 504         }
 505         info->info_block = kzalloc(sizeof(*info->info_block),
 506                                    GFP_DMA | GFP_KERNEL);
 507         if (!info->info_block) {
 508                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 509                 err = -ENOMEM;
 510                 goto out_err;
 511         }
 512         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 513         if (info->num < 0) {
 514                 err = info->num;
 515                 goto out_err;
 516         }
 517         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 518         info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
 519         if (info->queue == NULL) {
 520                 dev_warn(&vcdev->cdev->dev, "no queue\n");
 521                 err = -ENOMEM;
 522                 goto out_err;
 523         }
 524
 525         vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
 526                                  true, ctx, info->queue, virtio_ccw_kvm_notify,
 527                                  callback, name);
 528         if (!vq) {
 529                 /* For now, we fail if we can't get the requested size. */
 530                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 531                 err = -ENOMEM;
 532                 goto out_err;
 533         }
 534
 535         /* Register it with the host. */
 536         if (vcdev->revision == 0) {
 537                 info->info_block->l.queue = (__u64)info->queue;
 538                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 539                 info->info_block->l.index = i;
 540                 info->info_block->l.num = info->num;
 541                 ccw->count = sizeof(info->info_block->l);
 542         } else {
 543                 info->info_block->s.desc = (__u64)info->queue;
 544                 info->info_block->s.index = i;
 545                 info->info_block->s.num = info->num;
 546                 info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
 547                 info->info_block->s.used = (__u64)virtqueue_get_used(vq);
 548                 ccw->count = sizeof(info->info_block->s);
 549         }
 550         ccw->cmd_code = CCW_CMD_SET_VQ;
 551         ccw->flags = 0;
 552         ccw->cda = (__u32)(unsigned long)(info->info_block);
 553         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 554         if (err) {
 555                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 556                 goto out_err;
 557         }
 558
 559         info->vq = vq;
 560         vq->priv = info;
 561
 562         /* Save it to our list. */
 563         spin_lock_irqsave(&vcdev->lock, flags);
 564         list_add(&info->node, &vcdev->virtqueues);
 565         spin_unlock_irqrestore(&vcdev->lock, flags);
 566
 567         return vq;
 568
 569 out_err:
 570         if (vq)
 571                 vring_del_virtqueue(vq);
 572         if (info) {
 573                 if (info->queue)
 574                         free_pages_exact(info->queue, size);
 575                 kfree(info->info_block);
 576         }
 577         kfree(info);
 578         return ERR_PTR(err);
 579 }
 580
 581 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 582                                            struct virtqueue *vqs[], int nvqs,
 583                                            struct ccw1 *ccw)
 584 {
 585         int ret;
 586         struct virtio_thinint_area *thinint_area = NULL;
 587         struct airq_info *info;
 588
 589         thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
 590         if (!thinint_area) {
 591                 ret = -ENOMEM;
 592                 goto out;
 593         }
 594         /* Try to get an indicator. */
 595         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 596                                                      &thinint_area->bit_nr,
 597                                                      &vcdev->airq_info);
 598         if (!thinint_area->indicator) {
 599                 ret = -ENOSPC;
 600                 goto out;
 601         }
 602         info = vcdev->airq_info;
 603         thinint_area->summary_indicator =
 604                 (unsigned long) &info->summary_indicator;
 605         thinint_area->isc = VIRTIO_AIRQ_ISC;
 606         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 607         ccw->flags = CCW_FLAG_SLI;
 608         ccw->count = sizeof(*thinint_area);
 609         ccw->cda = (__u32)(unsigned long)thinint_area;
 610         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 611         if (ret) {
 612                 if (ret == -EOPNOTSUPP) {
 613                         /*
 614                          * The host does not support adapter interrupts
 615                          * for virtio-ccw, stop trying.
 616                          */
 617                         virtio_ccw_use_airq = 0;
 618                         pr_info("Adapter interrupts unsupported on host\n");
 619                 } else
 620                         dev_warn(&vcdev->cdev->dev,
 621                                  "enabling adapter interrupts = %d\n", ret);
 622                 virtio_ccw_drop_indicators(vcdev);
 623         }
 624 out:
 625         kfree(thinint_area);
 626         return ret;
 627 }
 628
 629 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 630                                struct virtqueue *vqs[],
 631                                vq_callback_t *callbacks[],
 632                                const char * const names[],
 633                                const bool *ctx,
 634                                struct irq_affinity *desc)
 635 {
 636         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 637         unsigned long *indicatorp = NULL;
 638         int ret, i;
 639         struct ccw1 *ccw;
 640
 641         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 642         if (!ccw)
 643                 return -ENOMEM;
 644
 645         for (i = 0; i < nvqs; ++i) {
 646                 vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
 647                                              ctx ? ctx[i] : false, ccw);
 648                 if (IS_ERR(vqs[i])) {
 649                         ret = PTR_ERR(vqs[i]);
 650                         vqs[i] = NULL;
 651                         goto out;
 652                 }
 653         }
 654         ret = -ENOMEM;
 655         /*
 656          * We need a data area under 2G to communicate. Our payload is
 657          * the address of the indicators.
 658         */
 659         indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
 660         if (!indicatorp)
 661                 goto out;
 662         *indicatorp = (unsigned long) &vcdev->indicators;
 663         if (vcdev->is_thinint) {
 664                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 665                 if (ret)
 666                         /* no error, just fall back to legacy interrupts */
 667                         vcdev->is_thinint = false;
 668         }
 669         if (!vcdev->is_thinint) {
 670                 /* Register queue indicators with host. */
 671                 vcdev->indicators = 0;
 672                 ccw->cmd_code = CCW_CMD_SET_IND;
 673                 ccw->flags = 0;
 674                 ccw->count = sizeof(&vcdev->indicators);
 675                 ccw->cda = (__u32)(unsigned long) indicatorp;
 676                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 677                 if (ret)
 678                         goto out;
 679         }
 680         /* Register indicators2 with host for config changes */
 681         *indicatorp = (unsigned long) &vcdev->indicators2;
 682         vcdev->indicators2 = 0;
 683         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 684         ccw->flags = 0;
 685         ccw->count = sizeof(&vcdev->indicators2);
 686         ccw->cda = (__u32)(unsigned long) indicatorp;
 687         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 688         if (ret)
 689                 goto out;
 690
 691         kfree(indicatorp);
 692         kfree(ccw);
 693         return 0;
 694 out:
 695         kfree(indicatorp);
 696         kfree(ccw);
 697         virtio_ccw_del_vqs(vdev);
 698         return ret;
 699 }
 700
 701 static void virtio_ccw_reset(struct virtio_device *vdev)
 702 {
 703         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 704         struct ccw1 *ccw;
 705
 706         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 707         if (!ccw)
 708                 return;
 709
 710         /* Zero status bits. */
 711         *vcdev->status = 0;
 712
 713         /* Send a reset ccw on device. */
 714         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 715         ccw->flags = 0;
 716         ccw->count = 0;
 717         ccw->cda = 0;
 718         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 719         kfree(ccw);
 720 }
 721
 722 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 723 {
 724         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 725         struct virtio_feature_desc *features;
 726         int ret;
 727         u64 rc;
 728         struct ccw1 *ccw;
 729
 730         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 731         if (!ccw)
 732                 return 0;
 733
 734         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 735         if (!features) {
 736                 rc = 0;
 737                 goto out_free;
 738         }
 739         /* Read the feature bits from the host. */
 740         features->index = 0;
 741         ccw->cmd_code = CCW_CMD_READ_FEAT;
 742         ccw->flags = 0;
 743         ccw->count = sizeof(*features);
 744         ccw->cda = (__u32)(unsigned long)features;
 745         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 746         if (ret) {
 747                 rc = 0;
 748                 goto out_free;
 749         }
 750
 751         rc = le32_to_cpu(features->features);
 752
 753         if (vcdev->revision == 0)
 754                 goto out_free;
 755
 756         /* Read second half of the feature bits from the host. */
 757         features->index = 1;
 758         ccw->cmd_code = CCW_CMD_READ_FEAT;
 759         ccw->flags = 0;
 760         ccw->count = sizeof(*features);
 761         ccw->cda = (__u32)(unsigned long)features;
 762         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 763         if (ret == 0)
 764                 rc |= (u64)le32_to_cpu(features->features) << 32;
 765
 766 out_free:
 767         kfree(features);
 768         kfree(ccw);
 769         return rc;
 770 }
 771
 772 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 773 {
 774         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 775         struct virtio_feature_desc *features;
 776         struct ccw1 *ccw;
 777         int ret;
 778
 779         if (vcdev->revision >= 1 &&
 780             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 781                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 782                         "but does not have VIRTIO_F_VERSION_1\n");
 783                 return -EINVAL;
 784         }
 785
 786         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 787         if (!ccw)
 788                 return -ENOMEM;
 789
 790         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 791         if (!features) {
 792                 ret = -ENOMEM;
 793                 goto out_free;
 794         }
 795         /* Give virtio_ring a chance to accept features. */
 796         vring_transport_features(vdev);
 797
 798         features->index = 0;
 799         features->features = cpu_to_le32((u32)vdev->features);
 800         /* Write the first half of the feature bits to the host. */
 801         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 802         ccw->flags = 0;
 803         ccw->count = sizeof(*features);
 804         ccw->cda = (__u32)(unsigned long)features;
 805         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 806         if (ret)
 807                 goto out_free;
 808
 809         if (vcdev->revision == 0)
 810                 goto out_free;
 811
 812         features->index = 1;
 813         features->features = cpu_to_le32(vdev->features >> 32);
 814         /* Write the second half of the feature bits to the host. */
 815         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 816         ccw->flags = 0;
 817         ccw->count = sizeof(*features);
 818         ccw->cda = (__u32)(unsigned long)features;
 819         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 820
 821 out_free:
 822         kfree(features);
 823         kfree(ccw);
 824
 825         return ret;
 826 }
 827
 828 static void virtio_ccw_get_config(struct virtio_device *vdev,
 829                                   unsigned int offset, void *buf, unsigned len)
 830 {
 831         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 832         int ret;
 833         struct ccw1 *ccw;
 834         void *config_area;
 835         unsigned long flags;
 836
 837         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 838         if (!ccw)
 839                 return;
 840
 841         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 842         if (!config_area)
 843                 goto out_free;
 844
 845         /* Read the config area from the host. */
 846         ccw->cmd_code = CCW_CMD_READ_CONF;
 847         ccw->flags = 0;
 848         ccw->count = offset + len;
 849         ccw->cda = (__u32)(unsigned long)config_area;
 850         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 851         if (ret)
 852                 goto out_free;
 853
 854         spin_lock_irqsave(&vcdev->lock, flags);
 855         memcpy(vcdev->config, config_area, offset + len);
 856         if (vcdev->config_ready < offset + len)
 857                 vcdev->config_ready = offset + len;
 858         spin_unlock_irqrestore(&vcdev->lock, flags);
 859         if (buf)
 860                 memcpy(buf, config_area + offset, len);
 861
 862 out_free:
 863         kfree(config_area);
 864         kfree(ccw);
 865 }
 866
 867 static void virtio_ccw_set_config(struct virtio_device *vdev,
 868                                   unsigned int offset, const void *buf,
 869                                   unsigned len)
 870 {
 871         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 872         struct ccw1 *ccw;
 873         void *config_area;
 874         unsigned long flags;
 875
 876         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 877         if (!ccw)
 878                 return;
 879
 880         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 881         if (!config_area)
 882                 goto out_free;
 883
 884         /* Make sure we don't overwrite fields. */
 885         if (vcdev->config_ready < offset)
 886                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 887         spin_lock_irqsave(&vcdev->lock, flags);
 888         memcpy(&vcdev->config[offset], buf, len);
 889         /* Write the config area to the host. */
 890         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 891         spin_unlock_irqrestore(&vcdev->lock, flags);
 892         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 893         ccw->flags = 0;
 894         ccw->count = offset + len;
 895         ccw->cda = (__u32)(unsigned long)config_area;
 896         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 897
 898 out_free:
 899         kfree(config_area);
 900         kfree(ccw);
 901 }
 902
 903 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 904 {
 905         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 906         u8 old_status = *vcdev->status;
 907         struct ccw1 *ccw;
 908
 909         if (vcdev->revision < 1)
 910                 return *vcdev->status;
 911
 912         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 913         if (!ccw)
 914                 return old_status;
 915
 916         ccw->cmd_code = CCW_CMD_READ_STATUS;
 917         ccw->flags = 0;
 918         ccw->count = sizeof(*vcdev->status);
 919         ccw->cda = (__u32)(unsigned long)vcdev->status;
 920         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 921 /*
 922  * If the channel program failed (should only happen if the device
 923  * was hotunplugged, and then we clean up via the machine check
 924  * handler anyway), vcdev->status was not overwritten and we just
 925  * return the old status, which is fine.
 926 */
 927         kfree(ccw);
 928
 929         return *vcdev->status;
 930 }
 931
 932 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 933 {
 934         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 935         u8 old_status = *vcdev->status;
 936         struct ccw1 *ccw;
 937         int ret;
 938
 939         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 940         if (!ccw)
 941                 return;
 942
 943         /* Write the status to the host. */
 944         *vcdev->status = status;
 945         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 946         ccw->flags = 0;
 947         ccw->count = sizeof(status);
 948         ccw->cda = (__u32)(unsigned long)vcdev->status;
 949         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 950         /* Write failed? We assume status is unchanged. */
 951         if (ret)
 952                 *vcdev->status = old_status;
 953         kfree(ccw);
 954 }
 955
 956 static const struct virtio_config_ops virtio_ccw_config_ops = {
 957         .get_features = virtio_ccw_get_features,
 958         .finalize_features = virtio_ccw_finalize_features,
 959         .get = virtio_ccw_get_config,
 960         .set = virtio_ccw_set_config,
 961         .get_status = virtio_ccw_get_status,
 962         .set_status = virtio_ccw_set_status,
 963         .reset = virtio_ccw_reset,
 964         .find_vqs = virtio_ccw_find_vqs,
 965         .del_vqs = virtio_ccw_del_vqs,
 966 };
 967
 968
 969 /*
 970  * ccw bus driver related functions
 971  */
 972
 973 static void virtio_ccw_release_dev(struct device *_d)
 974 {
 975         struct virtio_device *dev = dev_to_virtio(_d);
 976         struct virtio_ccw_device *vcdev = to_vc_device(dev);
 977
 978         kfree(vcdev->status);
 979         kfree(vcdev->config_block);
 980         kfree(vcdev);
 981 }
 982
 983 static int irb_is_error(struct irb *irb)
 984 {
 985         if (scsw_cstat(&irb->scsw) != 0)
 986                 return 1;
 987         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
 988                 return 1;
 989         if (scsw_cc(&irb->scsw) != 0)
 990                 return 1;
 991         return 0;
 992 }
 993
 994 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
 995                                               int index)
 996 {
 997         struct virtio_ccw_vq_info *info;
 998         unsigned long flags;
 999         struct virtqueue *vq;
1000
1001         vq = NULL;
1002         spin_lock_irqsave(&vcdev->lock, flags);
1003         list_for_each_entry(info, &vcdev->virtqueues, node) {
1004                 if (info->vq->index == index) {
1005                         vq = info->vq;
1006                         break;
1007                 }
1008         }
1009         spin_unlock_irqrestore(&vcdev->lock, flags);
1010         return vq;
1011 }
1012
1013 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1014                                       __u32 activity)
1015 {
1016         if (vcdev->curr_io & activity) {
1017                 switch (activity) {
1018                 case VIRTIO_CCW_DOING_READ_FEAT:
1019                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1020                 case VIRTIO_CCW_DOING_READ_CONFIG:
1021                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1022                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1023                 case VIRTIO_CCW_DOING_READ_STATUS:
1024                 case VIRTIO_CCW_DOING_SET_VQ:
1025                 case VIRTIO_CCW_DOING_SET_IND:
1026                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1027                 case VIRTIO_CCW_DOING_RESET:
1028                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1029                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1030                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1031                         vcdev->curr_io &= ~activity;
1032                         wake_up(&vcdev->wait_q);
1033                         break;
1034                 default:
1035                         /* don't know what to do... */
1036                         dev_warn(&vcdev->cdev->dev,
1037                                  "Suspicious activity '%08x'\n", activity);
1038                         WARN_ON(1);
1039                         break;
1040                 }
1041         }
1042 }
1043
1044 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1045                                    unsigned long intparm,
1046                                    struct irb *irb)
1047 {
1048         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1049         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1050         int i;
1051         struct virtqueue *vq;
1052
1053         if (!vcdev)
1054                 return;
1055         if (IS_ERR(irb)) {
1056                 vcdev->err = PTR_ERR(irb);
1057                 virtio_ccw_check_activity(vcdev, activity);
1058                 /* Don't poke around indicators, something's wrong. */
1059                 return;
1060         }
1061         /* Check if it's a notification from the host. */
1062         if ((intparm == 0) &&
1063             (scsw_stctl(&irb->scsw) ==
1064              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1065                 /* OK */
1066         }
1067         if (irb_is_error(irb)) {
1068                 /* Command reject? */
1069                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1070                     (irb->ecw[0] & SNS0_CMD_REJECT))
1071                         vcdev->err = -EOPNOTSUPP;
1072                 else
1073                         /* Map everything else to -EIO. */
1074                         vcdev->err = -EIO;
1075         }
1076         virtio_ccw_check_activity(vcdev, activity);
1077         for_each_set_bit(i, &vcdev->indicators,
1078                          sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1079                 /* The bit clear must happen before the vring kick. */
1080                 clear_bit(i, &vcdev->indicators);
1081                 barrier();
1082                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1083                 vring_interrupt(0, vq);
1084         }
1085         if (test_bit(0, &vcdev->indicators2)) {
1086                 virtio_config_changed(&vcdev->vdev);
1087                 clear_bit(0, &vcdev->indicators2);
1088         }
1089 }
1090
1091 /*
1092  * We usually want to autoonline all devices, but give the admin
1093  * a way to exempt devices from this.
1094  */
1095 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1096                      (8*sizeof(long)))
1097 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1098
1099 static char *no_auto = "";
1100
1101 module_param(no_auto, charp, 0444);
1102 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1103
1104 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1105 {
1106         struct ccw_dev_id id;
1107
1108         ccw_device_get_id(cdev, &id);
1109         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1110                 return 0;
1111         return 1;
1112 }
1113
1114 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1115 {
1116         struct ccw_device *cdev = data;
1117         int ret;
1118
1119         ret = ccw_device_set_online(cdev);
1120         if (ret)
1121                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1122 }
1123
1124 static int virtio_ccw_probe(struct ccw_device *cdev)
1125 {
1126         cdev->handler = virtio_ccw_int_handler;
1127
1128         if (virtio_ccw_check_autoonline(cdev))
1129                 async_schedule(virtio_ccw_auto_online, cdev);
1130         return 0;
1131 }
1132
1133 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1134 {
1135         unsigned long flags;
1136         struct virtio_ccw_device *vcdev;
1137
1138         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1139         vcdev = dev_get_drvdata(&cdev->dev);
1140         if (!vcdev || vcdev->going_away) {
1141                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1142                 return NULL;
1143         }
1144         vcdev->going_away = true;
1145         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1146         return vcdev;
1147 }
1148
1149 static void virtio_ccw_remove(struct ccw_device *cdev)
1150 {
1151         unsigned long flags;
1152         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1153
1154         if (vcdev && cdev->online) {
1155                 if (vcdev->device_lost)
1156                         virtio_break_device(&vcdev->vdev);
1157                 unregister_virtio_device(&vcdev->vdev);
1158                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1159                 dev_set_drvdata(&cdev->dev, NULL);
1160                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1161         }
1162         cdev->handler = NULL;
1163 }
1164
1165 static int virtio_ccw_offline(struct ccw_device *cdev)
1166 {
1167         unsigned long flags;
1168         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1169
1170         if (!vcdev)
1171                 return 0;
1172         if (vcdev->device_lost)
1173                 virtio_break_device(&vcdev->vdev);
1174         unregister_virtio_device(&vcdev->vdev);
1175         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1176         dev_set_drvdata(&cdev->dev, NULL);
1177         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1178         return 0;
1179 }
1180
1181 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1182 {
1183         struct virtio_rev_info *rev;
1184         struct ccw1 *ccw;
1185         int ret;
1186
1187         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1188         if (!ccw)
1189                 return -ENOMEM;
1190         rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1191         if (!rev) {
1192                 kfree(ccw);
1193                 return -ENOMEM;
1194         }
1195
1196         /* Set transport revision */
1197         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1198         ccw->flags = 0;
1199         ccw->count = sizeof(*rev);
1200         ccw->cda = (__u32)(unsigned long)rev;
1201
1202         vcdev->revision = VIRTIO_CCW_REV_MAX;
1203         do {
1204                 rev->revision = vcdev->revision;
1205                 /* none of our supported revisions carry payload */
1206                 rev->length = 0;
1207                 ret = ccw_io_helper(vcdev, ccw,
1208                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1209                 if (ret == -EOPNOTSUPP) {
1210                         if (vcdev->revision == 0)
1211                                 /*
1212                                  * The host device does not support setting
1213                                  * the revision: let's operate it in legacy
1214                                  * mode.
1215                                  */
1216                                 ret = 0;
1217                         else
1218                                 vcdev->revision--;
1219                 }
1220         } while (ret == -EOPNOTSUPP);
1221
1222         kfree(ccw);
1223         kfree(rev);
1224         return ret;
1225 }
1226
1227 static int virtio_ccw_online(struct ccw_device *cdev)
1228 {
1229         int ret;
1230         struct virtio_ccw_device *vcdev;
1231         unsigned long flags;
1232
1233         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1234         if (!vcdev) {
1235                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1236                 ret = -ENOMEM;
1237                 goto out_free;
1238         }
1239         vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1240                                    GFP_DMA | GFP_KERNEL);
1241         if (!vcdev->config_block) {
1242                 ret = -ENOMEM;
1243                 goto out_free;
1244         }
1245         vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1246         if (!vcdev->status) {
1247                 ret = -ENOMEM;
1248                 goto out_free;
1249         }
1250
1251         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1252
1253         vcdev->vdev.dev.parent = &cdev->dev;
1254         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1255         vcdev->vdev.config = &virtio_ccw_config_ops;
1256         vcdev->cdev = cdev;
1257         init_waitqueue_head(&vcdev->wait_q);
1258         INIT_LIST_HEAD(&vcdev->virtqueues);
1259         spin_lock_init(&vcdev->lock);
1260         mutex_init(&vcdev->io_lock);
1261
1262         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1263         dev_set_drvdata(&cdev->dev, vcdev);
1264         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1265         vcdev->vdev.id.vendor = cdev->id.cu_type;
1266         vcdev->vdev.id.device = cdev->id.cu_model;
1267
1268         ret = virtio_ccw_set_transport_rev(vcdev);
1269         if (ret)
1270                 goto out_free;
1271
1272         ret = register_virtio_device(&vcdev->vdev);
1273         if (ret) {
1274                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1275                          ret);
1276                 goto out_put;
1277         }
1278         return 0;
1279 out_put:
1280         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1281         dev_set_drvdata(&cdev->dev, NULL);
1282         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1283         put_device(&vcdev->vdev.dev);
1284         return ret;
1285 out_free:
1286         if (vcdev) {
1287                 kfree(vcdev->status);
1288                 kfree(vcdev->config_block);
1289         }
1290         kfree(vcdev);
1291         return ret;
1292 }
1293
1294 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1295 {
1296         int rc;
1297         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1298
1299         /*
1300          * Make sure vcdev is set
1301          * i.e. set_offline/remove callback not already running
1302          */
1303         if (!vcdev)
1304                 return NOTIFY_DONE;
1305
1306         switch (event) {
1307         case CIO_GONE:
1308                 vcdev->device_lost = true;
1309                 rc = NOTIFY_DONE;
1310                 break;
1311         case CIO_OPER:
1312                 rc = NOTIFY_OK;
1313                 break;
1314         default:
1315                 rc = NOTIFY_DONE;
1316                 break;
1317         }
1318         return rc;
1319 }
1320
1321 static struct ccw_device_id virtio_ids[] = {
1322         { CCW_DEVICE(0x3832, 0) },
1323         {},
1324 };
1325
1326 #ifdef CONFIG_PM_SLEEP
1327 static int virtio_ccw_freeze(struct ccw_device *cdev)
1328 {
1329         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1330
1331         return virtio_device_freeze(&vcdev->vdev);
1332 }
1333
1334 static int virtio_ccw_restore(struct ccw_device *cdev)
1335 {
1336         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1337         int ret;
1338
1339         ret = virtio_ccw_set_transport_rev(vcdev);
1340         if (ret)
1341                 return ret;
1342
1343         return virtio_device_restore(&vcdev->vdev);
1344 }
1345 #endif
1346
1347 static struct ccw_driver virtio_ccw_driver = {
1348         .driver = {
1349                 .owner = THIS_MODULE,
1350                 .name = "virtio_ccw",
1351         },
1352         .ids = virtio_ids,
1353         .probe = virtio_ccw_probe,
1354         .remove = virtio_ccw_remove,
1355         .set_offline = virtio_ccw_offline,
1356         .set_online = virtio_ccw_online,
1357         .notify = virtio_ccw_cio_notify,
1358         .int_class = IRQIO_VIR,
1359 #ifdef CONFIG_PM_SLEEP
1360         .freeze = virtio_ccw_freeze,
1361         .thaw = virtio_ccw_restore,
1362         .restore = virtio_ccw_restore,
1363 #endif
1364 };
1365
1366 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1367                            int max_digit, int max_val)
1368 {
1369         int diff;
1370
1371         diff = 0;
1372         *val = 0;
1373
1374         while (diff <= max_digit) {
1375                 int value = hex_to_bin(**cp);
1376
1377                 if (value < 0)
1378                         break;
1379                 *val = *val * 16 + value;
1380                 (*cp)++;
1381                 diff++;
1382         }
1383
1384         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1385                 return 1;
1386
1387         return 0;
1388 }
1389
1390 static int __init parse_busid(char *str, unsigned int *cssid,
1391                               unsigned int *ssid, unsigned int *devno)
1392 {
1393         char *str_work;
1394         int rc, ret;
1395
1396         rc = 1;
1397
1398         if (*str == '\0')
1399                 goto out;
1400
1401         str_work = str;
1402         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1403         if (ret || (str_work[0] != '.'))
1404                 goto out;
1405         str_work++;
1406         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1407         if (ret || (str_work[0] != '.'))
1408                 goto out;
1409         str_work++;
1410         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1411         if (ret || (str_work[0] != '\0'))
1412                 goto out;
1413
1414         rc = 0;
1415 out:
1416         return rc;
1417 }
1418
1419 static void __init no_auto_parse(void)
1420 {
1421         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1422         char *parm, *str;
1423         int rc;
1424
1425         str = no_auto;
1426         while ((parm = strsep(&str, ","))) {
1427                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1428                                  &from_ssid, &from);
1429                 if (rc)
1430                         continue;
1431                 if (parm != NULL) {
1432                         rc = parse_busid(parm, &to_cssid,
1433                                          &to_ssid, &to);
1434                         if ((from_ssid > to_ssid) ||
1435                             ((from_ssid == to_ssid) && (from > to)))
1436                                 rc = -EINVAL;
1437                 } else {
1438                         to_cssid = from_cssid;
1439                         to_ssid = from_ssid;
1440                         to = from;
1441                 }
1442                 if (rc)
1443                         continue;
1444                 while ((from_ssid < to_ssid) ||
1445                        ((from_ssid == to_ssid) && (from <= to))) {
1446                         set_bit(from, devs_no_auto[from_ssid]);
1447                         from++;
1448                         if (from > __MAX_SUBCHANNEL) {
1449                                 from_ssid++;
1450                                 from = 0;
1451                         }
1452                 }
1453         }
1454 }
1455
1456 static int __init virtio_ccw_init(void)
1457 {
1458         /* parse no_auto string before we do anything further */
1459         no_auto_parse();
1460         return ccw_driver_register(&virtio_ccw_driver);
1461 }
1462 device_initcall(virtio_ccw_init);