drivers/s390/virtio/virtio_ccw.c

   1 /*
   2  * ccw based virtio transport
   3  *
   4  * Copyright IBM Corp. 2012, 2014
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License (version 2 only)
   8  * as published by the Free Software Foundation.
   9  *
  10  *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
  11  */
  12
  13 #include <linux/kernel_stat.h>
  14 #include <linux/init.h>
  15 #include <linux/bootmem.h>
  16 #include <linux/err.h>
  17 #include <linux/virtio.h>
  18 #include <linux/virtio_config.h>
  19 #include <linux/slab.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/virtio_ring.h>
  22 #include <linux/pfn.h>
  23 #include <linux/async.h>
  24 #include <linux/wait.h>
  25 #include <linux/list.h>
  26 #include <linux/bitops.h>
  27 #include <linux/module.h>
  28 #include <linux/io.h>
  29 #include <linux/kvm_para.h>
  30 #include <linux/notifier.h>
  31 #include <asm/diag.h>
  32 #include <asm/setup.h>
  33 #include <asm/irq.h>
  34 #include <asm/cio.h>
  35 #include <asm/ccwdev.h>
  36 #include <asm/virtio-ccw.h>
  37 #include <asm/isc.h>
  38 #include <asm/airq.h>
  39
  40 /*
  41  * virtio related functions
  42  */
  43
  44 struct vq_config_block {
  45         __u16 index;
  46         __u16 num;
  47 } __packed;
  48
  49 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  50 /* same as PCI config space size, should be enough for all drivers */
  51
  52 struct virtio_ccw_device {
  53         struct virtio_device vdev;
  54         __u8 *status;
  55         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  56         struct ccw_device *cdev;
  57         __u32 curr_io;
  58         int err;
  59         unsigned int revision; /* Transport revision */
  60         wait_queue_head_t wait_q;
  61         spinlock_t lock;
  62         struct mutex io_lock; /* Serializes I/O requests */
  63         struct list_head virtqueues;
  64         unsigned long indicators;
  65         unsigned long indicators2;
  66         struct vq_config_block *config_block;
  67         bool is_thinint;
  68         bool going_away;
  69         bool device_lost;
  70         unsigned int config_ready;
  71         void *airq_info;
  72 };
  73
  74 struct vq_info_block_legacy {
  75         __u64 queue;
  76         __u32 align;
  77         __u16 index;
  78         __u16 num;
  79 } __packed;
  80
  81 struct vq_info_block {
  82         __u64 desc;
  83         __u32 res0;
  84         __u16 index;
  85         __u16 num;
  86         __u64 avail;
  87         __u64 used;
  88 } __packed;
  89
  90 struct virtio_feature_desc {
  91         __u32 features;
  92         __u8 index;
  93 } __packed;
  94
  95 struct virtio_thinint_area {
  96         unsigned long summary_indicator;
  97         unsigned long indicator;
  98         u64 bit_nr;
  99         u8 isc;
 100 } __packed;
 101
 102 struct virtio_rev_info {
 103         __u16 revision;
 104         __u16 length;
 105         __u8 data[];
 106 };
 107
 108 /* the highest virtio-ccw revision we support */
 109 #define VIRTIO_CCW_REV_MAX 1
 110
 111 struct virtio_ccw_vq_info {
 112         struct virtqueue *vq;
 113         int num;
 114         void *queue;
 115         union {
 116                 struct vq_info_block s;
 117                 struct vq_info_block_legacy l;
 118         } *info_block;
 119         int bit_nr;
 120         struct list_head node;
 121         long cookie;
 122 };
 123
 124 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 125
 126 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 127 #define MAX_AIRQ_AREAS 20
 128
 129 static int virtio_ccw_use_airq = 1;
 130
 131 struct airq_info {
 132         rwlock_t lock;
 133         u8 summary_indicator;
 134         struct airq_struct airq;
 135         struct airq_iv *aiv;
 136 };
 137 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 138
 139 #define CCW_CMD_SET_VQ 0x13
 140 #define CCW_CMD_VDEV_RESET 0x33
 141 #define CCW_CMD_SET_IND 0x43
 142 #define CCW_CMD_SET_CONF_IND 0x53
 143 #define CCW_CMD_READ_FEAT 0x12
 144 #define CCW_CMD_WRITE_FEAT 0x11
 145 #define CCW_CMD_READ_CONF 0x22
 146 #define CCW_CMD_WRITE_CONF 0x21
 147 #define CCW_CMD_WRITE_STATUS 0x31
 148 #define CCW_CMD_READ_VQ_CONF 0x32
 149 #define CCW_CMD_SET_IND_ADAPTER 0x73
 150 #define CCW_CMD_SET_VIRTIO_REV 0x83
 151
 152 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 153 #define VIRTIO_CCW_DOING_RESET 0x00040000
 154 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 155 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 156 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 157 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 158 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 159 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 160 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 161 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 162 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 163 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 164 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 165
 166 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 167 {
 168         return container_of(vdev, struct virtio_ccw_device, vdev);
 169 }
 170
 171 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 172 {
 173         unsigned long i, flags;
 174
 175         write_lock_irqsave(&info->lock, flags);
 176         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 177                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 178                         airq_iv_free_bit(info->aiv, i);
 179                         airq_iv_set_ptr(info->aiv, i, 0);
 180                         break;
 181                 }
 182         }
 183         write_unlock_irqrestore(&info->lock, flags);
 184 }
 185
 186 static void virtio_airq_handler(struct airq_struct *airq)
 187 {
 188         struct airq_info *info = container_of(airq, struct airq_info, airq);
 189         unsigned long ai;
 190
 191         inc_irq_stat(IRQIO_VAI);
 192         read_lock(&info->lock);
 193         /* Walk through indicators field, summary indicator active. */
 194         for (ai = 0;;) {
 195                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 196                 if (ai == -1UL)
 197                         break;
 198                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 199         }
 200         info->summary_indicator = 0;
 201         smp_wmb();
 202         /* Walk through indicators field, summary indicator not active. */
 203         for (ai = 0;;) {
 204                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 205                 if (ai == -1UL)
 206                         break;
 207                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 208         }
 209         read_unlock(&info->lock);
 210 }
 211
 212 static struct airq_info *new_airq_info(void)
 213 {
 214         struct airq_info *info;
 215         int rc;
 216
 217         info = kzalloc(sizeof(*info), GFP_KERNEL);
 218         if (!info)
 219                 return NULL;
 220         rwlock_init(&info->lock);
 221         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
 222         if (!info->aiv) {
 223                 kfree(info);
 224                 return NULL;
 225         }
 226         info->airq.handler = virtio_airq_handler;
 227         info->airq.lsi_ptr = &info->summary_indicator;
 228         info->airq.lsi_mask = 0xff;
 229         info->airq.isc = VIRTIO_AIRQ_ISC;
 230         rc = register_adapter_interrupt(&info->airq);
 231         if (rc) {
 232                 airq_iv_release(info->aiv);
 233                 kfree(info);
 234                 return NULL;
 235         }
 236         return info;
 237 }
 238
 239 static void destroy_airq_info(struct airq_info *info)
 240 {
 241         if (!info)
 242                 return;
 243
 244         unregister_adapter_interrupt(&info->airq);
 245         airq_iv_release(info->aiv);
 246         kfree(info);
 247 }
 248
 249 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 250                                         u64 *first, void **airq_info)
 251 {
 252         int i, j;
 253         struct airq_info *info;
 254         unsigned long indicator_addr = 0;
 255         unsigned long bit, flags;
 256
 257         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 258                 if (!airq_areas[i])
 259                         airq_areas[i] = new_airq_info();
 260                 info = airq_areas[i];
 261                 if (!info)
 262                         return 0;
 263                 write_lock_irqsave(&info->lock, flags);
 264                 bit = airq_iv_alloc(info->aiv, nvqs);
 265                 if (bit == -1UL) {
 266                         /* Not enough vacancies. */
 267                         write_unlock_irqrestore(&info->lock, flags);
 268                         continue;
 269                 }
 270                 *first = bit;
 271                 *airq_info = info;
 272                 indicator_addr = (unsigned long)info->aiv->vector;
 273                 for (j = 0; j < nvqs; j++) {
 274                         airq_iv_set_ptr(info->aiv, bit + j,
 275                                         (unsigned long)vqs[j]);
 276                 }
 277                 write_unlock_irqrestore(&info->lock, flags);
 278         }
 279         return indicator_addr;
 280 }
 281
 282 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 283 {
 284         struct virtio_ccw_vq_info *info;
 285
 286         if (!vcdev->airq_info)
 287                 return;
 288         list_for_each_entry(info, &vcdev->virtqueues, node)
 289                 drop_airq_indicator(info->vq, vcdev->airq_info);
 290 }
 291
 292 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 293 {
 294         unsigned long flags;
 295         __u32 ret;
 296
 297         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 298         if (vcdev->err)
 299                 ret = 0;
 300         else
 301                 ret = vcdev->curr_io & flag;
 302         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 303         return ret;
 304 }
 305
 306 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 307                          struct ccw1 *ccw, __u32 intparm)
 308 {
 309         int ret;
 310         unsigned long flags;
 311         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 312
 313         mutex_lock(&vcdev->io_lock);
 314         do {
 315                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 316                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 317                 if (!ret) {
 318                         if (!vcdev->curr_io)
 319                                 vcdev->err = 0;
 320                         vcdev->curr_io |= flag;
 321                 }
 322                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 323                 cpu_relax();
 324         } while (ret == -EBUSY);
 325         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 326         ret = ret ? ret : vcdev->err;
 327         mutex_unlock(&vcdev->io_lock);
 328         return ret;
 329 }
 330
 331 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 332                                       struct ccw1 *ccw)
 333 {
 334         int ret;
 335         unsigned long *indicatorp = NULL;
 336         struct virtio_thinint_area *thinint_area = NULL;
 337         struct airq_info *airq_info = vcdev->airq_info;
 338
 339         if (vcdev->is_thinint) {
 340                 thinint_area = kzalloc(sizeof(*thinint_area),
 341                                        GFP_DMA | GFP_KERNEL);
 342                 if (!thinint_area)
 343                         return;
 344                 thinint_area->summary_indicator =
 345                         (unsigned long) &airq_info->summary_indicator;
 346                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 347                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 348                 ccw->count = sizeof(*thinint_area);
 349                 ccw->cda = (__u32)(unsigned long) thinint_area;
 350         } else {
 351                 /* payload is the address of the indicators */
 352                 indicatorp = kmalloc(sizeof(&vcdev->indicators),
 353                                      GFP_DMA | GFP_KERNEL);
 354                 if (!indicatorp)
 355                         return;
 356                 *indicatorp = 0;
 357                 ccw->cmd_code = CCW_CMD_SET_IND;
 358                 ccw->count = sizeof(&vcdev->indicators);
 359                 ccw->cda = (__u32)(unsigned long) indicatorp;
 360         }
 361         /* Deregister indicators from host. */
 362         vcdev->indicators = 0;
 363         ccw->flags = 0;
 364         ret = ccw_io_helper(vcdev, ccw,
 365                             vcdev->is_thinint ?
 366                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 367                             VIRTIO_CCW_DOING_SET_IND);
 368         if (ret && (ret != -ENODEV))
 369                 dev_info(&vcdev->cdev->dev,
 370                          "Failed to deregister indicators (%d)\n", ret);
 371         else if (vcdev->is_thinint)
 372                 virtio_ccw_drop_indicators(vcdev);
 373         kfree(indicatorp);
 374         kfree(thinint_area);
 375 }
 376
 377 static inline long __do_kvm_notify(struct subchannel_id schid,
 378                                    unsigned long queue_index,
 379                                    long cookie)
 380 {
 381         register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 382         register struct subchannel_id __schid asm("2") = schid;
 383         register unsigned long __index asm("3") = queue_index;
 384         register long __rc asm("2");
 385         register long __cookie asm("4") = cookie;
 386
 387         asm volatile ("diag 2,4,0x500\n"
 388                       : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 389                       "d"(__cookie)
 390                       : "memory", "cc");
 391         return __rc;
 392 }
 393
 394 static inline long do_kvm_notify(struct subchannel_id schid,
 395                                  unsigned long queue_index,
 396                                  long cookie)
 397 {
 398         diag_stat_inc(DIAG_STAT_X500);
 399         return __do_kvm_notify(schid, queue_index, cookie);
 400 }
 401
 402 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 403 {
 404         struct virtio_ccw_vq_info *info = vq->priv;
 405         struct virtio_ccw_device *vcdev;
 406         struct subchannel_id schid;
 407
 408         vcdev = to_vc_device(info->vq->vdev);
 409         ccw_device_get_schid(vcdev->cdev, &schid);
 410         info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 411         if (info->cookie < 0)
 412                 return false;
 413         return true;
 414 }
 415
 416 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 417                                    struct ccw1 *ccw, int index)
 418 {
 419         int ret;
 420
 421         vcdev->config_block->index = index;
 422         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 423         ccw->flags = 0;
 424         ccw->count = sizeof(struct vq_config_block);
 425         ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
 426         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 427         if (ret)
 428                 return ret;
 429         return vcdev->config_block->num ?: -ENOENT;
 430 }
 431
 432 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 433 {
 434         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 435         struct virtio_ccw_vq_info *info = vq->priv;
 436         unsigned long flags;
 437         unsigned long size;
 438         int ret;
 439         unsigned int index = vq->index;
 440
 441         /* Remove from our list. */
 442         spin_lock_irqsave(&vcdev->lock, flags);
 443         list_del(&info->node);
 444         spin_unlock_irqrestore(&vcdev->lock, flags);
 445
 446         /* Release from host. */
 447         if (vcdev->revision == 0) {
 448                 info->info_block->l.queue = 0;
 449                 info->info_block->l.align = 0;
 450                 info->info_block->l.index = index;
 451                 info->info_block->l.num = 0;
 452                 ccw->count = sizeof(info->info_block->l);
 453         } else {
 454                 info->info_block->s.desc = 0;
 455                 info->info_block->s.index = index;
 456                 info->info_block->s.num = 0;
 457                 info->info_block->s.avail = 0;
 458                 info->info_block->s.used = 0;
 459                 ccw->count = sizeof(info->info_block->s);
 460         }
 461         ccw->cmd_code = CCW_CMD_SET_VQ;
 462         ccw->flags = 0;
 463         ccw->cda = (__u32)(unsigned long)(info->info_block);
 464         ret = ccw_io_helper(vcdev, ccw,
 465                             VIRTIO_CCW_DOING_SET_VQ | index);
 466         /*
 467          * -ENODEV isn't considered an error: The device is gone anyway.
 468          * This may happen on device detach.
 469          */
 470         if (ret && (ret != -ENODEV))
 471                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d",
 472                          ret, index);
 473
 474         vring_del_virtqueue(vq);
 475         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 476         free_pages_exact(info->queue, size);
 477         kfree(info->info_block);
 478         kfree(info);
 479 }
 480
 481 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 482 {
 483         struct virtqueue *vq, *n;
 484         struct ccw1 *ccw;
 485         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 486
 487         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 488         if (!ccw)
 489                 return;
 490
 491         virtio_ccw_drop_indicator(vcdev, ccw);
 492
 493         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 494                 virtio_ccw_del_vq(vq, ccw);
 495
 496         kfree(ccw);
 497 }
 498
 499 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 500                                              int i, vq_callback_t *callback,
 501                                              const char *name,
 502                                              struct ccw1 *ccw)
 503 {
 504         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 505         int err;
 506         struct virtqueue *vq = NULL;
 507         struct virtio_ccw_vq_info *info;
 508         unsigned long size = 0; /* silence the compiler */
 509         unsigned long flags;
 510
 511         /* Allocate queue. */
 512         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 513         if (!info) {
 514                 dev_warn(&vcdev->cdev->dev, "no info\n");
 515                 err = -ENOMEM;
 516                 goto out_err;
 517         }
 518         info->info_block = kzalloc(sizeof(*info->info_block),
 519                                    GFP_DMA | GFP_KERNEL);
 520         if (!info->info_block) {
 521                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 522                 err = -ENOMEM;
 523                 goto out_err;
 524         }
 525         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 526         if (info->num < 0) {
 527                 err = info->num;
 528                 goto out_err;
 529         }
 530         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 531         info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
 532         if (info->queue == NULL) {
 533                 dev_warn(&vcdev->cdev->dev, "no queue\n");
 534                 err = -ENOMEM;
 535                 goto out_err;
 536         }
 537
 538         vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
 539                                  true, info->queue, virtio_ccw_kvm_notify,
 540                                  callback, name);
 541         if (!vq) {
 542                 /* For now, we fail if we can't get the requested size. */
 543                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 544                 err = -ENOMEM;
 545                 goto out_err;
 546         }
 547
 548         /* Register it with the host. */
 549         if (vcdev->revision == 0) {
 550                 info->info_block->l.queue = (__u64)info->queue;
 551                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 552                 info->info_block->l.index = i;
 553                 info->info_block->l.num = info->num;
 554                 ccw->count = sizeof(info->info_block->l);
 555         } else {
 556                 info->info_block->s.desc = (__u64)info->queue;
 557                 info->info_block->s.index = i;
 558                 info->info_block->s.num = info->num;
 559                 info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
 560                 info->info_block->s.used = (__u64)virtqueue_get_used(vq);
 561                 ccw->count = sizeof(info->info_block->s);
 562         }
 563         ccw->cmd_code = CCW_CMD_SET_VQ;
 564         ccw->flags = 0;
 565         ccw->cda = (__u32)(unsigned long)(info->info_block);
 566         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 567         if (err) {
 568                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 569                 goto out_err;
 570         }
 571
 572         info->vq = vq;
 573         vq->priv = info;
 574
 575         /* Save it to our list. */
 576         spin_lock_irqsave(&vcdev->lock, flags);
 577         list_add(&info->node, &vcdev->virtqueues);
 578         spin_unlock_irqrestore(&vcdev->lock, flags);
 579
 580         return vq;
 581
 582 out_err:
 583         if (vq)
 584                 vring_del_virtqueue(vq);
 585         if (info) {
 586                 if (info->queue)
 587                         free_pages_exact(info->queue, size);
 588                 kfree(info->info_block);
 589         }
 590         kfree(info);
 591         return ERR_PTR(err);
 592 }
 593
 594 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 595                                            struct virtqueue *vqs[], int nvqs,
 596                                            struct ccw1 *ccw)
 597 {
 598         int ret;
 599         struct virtio_thinint_area *thinint_area = NULL;
 600         struct airq_info *info;
 601
 602         thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
 603         if (!thinint_area) {
 604                 ret = -ENOMEM;
 605                 goto out;
 606         }
 607         /* Try to get an indicator. */
 608         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 609                                                      &thinint_area->bit_nr,
 610                                                      &vcdev->airq_info);
 611         if (!thinint_area->indicator) {
 612                 ret = -ENOSPC;
 613                 goto out;
 614         }
 615         info = vcdev->airq_info;
 616         thinint_area->summary_indicator =
 617                 (unsigned long) &info->summary_indicator;
 618         thinint_area->isc = VIRTIO_AIRQ_ISC;
 619         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 620         ccw->flags = CCW_FLAG_SLI;
 621         ccw->count = sizeof(*thinint_area);
 622         ccw->cda = (__u32)(unsigned long)thinint_area;
 623         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 624         if (ret) {
 625                 if (ret == -EOPNOTSUPP) {
 626                         /*
 627                          * The host does not support adapter interrupts
 628                          * for virtio-ccw, stop trying.
 629                          */
 630                         virtio_ccw_use_airq = 0;
 631                         pr_info("Adapter interrupts unsupported on host\n");
 632                 } else
 633                         dev_warn(&vcdev->cdev->dev,
 634                                  "enabling adapter interrupts = %d\n", ret);
 635                 virtio_ccw_drop_indicators(vcdev);
 636         }
 637 out:
 638         kfree(thinint_area);
 639         return ret;
 640 }
 641
 642 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 643                                struct virtqueue *vqs[],
 644                                vq_callback_t *callbacks[],
 645                                const char * const names[])
 646 {
 647         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 648         unsigned long *indicatorp = NULL;
 649         int ret, i;
 650         struct ccw1 *ccw;
 651
 652         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 653         if (!ccw)
 654                 return -ENOMEM;
 655
 656         for (i = 0; i < nvqs; ++i) {
 657                 vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
 658                                              ccw);
 659                 if (IS_ERR(vqs[i])) {
 660                         ret = PTR_ERR(vqs[i]);
 661                         vqs[i] = NULL;
 662                         goto out;
 663                 }
 664         }
 665         ret = -ENOMEM;
 666         /*
 667          * We need a data area under 2G to communicate. Our payload is
 668          * the address of the indicators.
 669         */
 670         indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
 671         if (!indicatorp)
 672                 goto out;
 673         *indicatorp = (unsigned long) &vcdev->indicators;
 674         if (vcdev->is_thinint) {
 675                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 676                 if (ret)
 677                         /* no error, just fall back to legacy interrupts */
 678                         vcdev->is_thinint = 0;
 679         }
 680         if (!vcdev->is_thinint) {
 681                 /* Register queue indicators with host. */
 682                 vcdev->indicators = 0;
 683                 ccw->cmd_code = CCW_CMD_SET_IND;
 684                 ccw->flags = 0;
 685                 ccw->count = sizeof(&vcdev->indicators);
 686                 ccw->cda = (__u32)(unsigned long) indicatorp;
 687                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 688                 if (ret)
 689                         goto out;
 690         }
 691         /* Register indicators2 with host for config changes */
 692         *indicatorp = (unsigned long) &vcdev->indicators2;
 693         vcdev->indicators2 = 0;
 694         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 695         ccw->flags = 0;
 696         ccw->count = sizeof(&vcdev->indicators2);
 697         ccw->cda = (__u32)(unsigned long) indicatorp;
 698         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 699         if (ret)
 700                 goto out;
 701
 702         kfree(indicatorp);
 703         kfree(ccw);
 704         return 0;
 705 out:
 706         kfree(indicatorp);
 707         kfree(ccw);
 708         virtio_ccw_del_vqs(vdev);
 709         return ret;
 710 }
 711
 712 static void virtio_ccw_reset(struct virtio_device *vdev)
 713 {
 714         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 715         struct ccw1 *ccw;
 716
 717         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 718         if (!ccw)
 719                 return;
 720
 721         /* Zero status bits. */
 722         *vcdev->status = 0;
 723
 724         /* Send a reset ccw on device. */
 725         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 726         ccw->flags = 0;
 727         ccw->count = 0;
 728         ccw->cda = 0;
 729         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 730         kfree(ccw);
 731 }
 732
 733 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 734 {
 735         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 736         struct virtio_feature_desc *features;
 737         int ret;
 738         u64 rc;
 739         struct ccw1 *ccw;
 740
 741         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 742         if (!ccw)
 743                 return 0;
 744
 745         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 746         if (!features) {
 747                 rc = 0;
 748                 goto out_free;
 749         }
 750         /* Read the feature bits from the host. */
 751         features->index = 0;
 752         ccw->cmd_code = CCW_CMD_READ_FEAT;
 753         ccw->flags = 0;
 754         ccw->count = sizeof(*features);
 755         ccw->cda = (__u32)(unsigned long)features;
 756         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 757         if (ret) {
 758                 rc = 0;
 759                 goto out_free;
 760         }
 761
 762         rc = le32_to_cpu(features->features);
 763
 764         if (vcdev->revision == 0)
 765                 goto out_free;
 766
 767         /* Read second half of the feature bits from the host. */
 768         features->index = 1;
 769         ccw->cmd_code = CCW_CMD_READ_FEAT;
 770         ccw->flags = 0;
 771         ccw->count = sizeof(*features);
 772         ccw->cda = (__u32)(unsigned long)features;
 773         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 774         if (ret == 0)
 775                 rc |= (u64)le32_to_cpu(features->features) << 32;
 776
 777 out_free:
 778         kfree(features);
 779         kfree(ccw);
 780         return rc;
 781 }
 782
 783 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 784 {
 785         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 786         struct virtio_feature_desc *features;
 787         struct ccw1 *ccw;
 788         int ret;
 789
 790         if (vcdev->revision >= 1 &&
 791             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 792                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 793                         "but does not have VIRTIO_F_VERSION_1\n");
 794                 return -EINVAL;
 795         }
 796
 797         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 798         if (!ccw)
 799                 return -ENOMEM;
 800
 801         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 802         if (!features) {
 803                 ret = -ENOMEM;
 804                 goto out_free;
 805         }
 806         /* Give virtio_ring a chance to accept features. */
 807         vring_transport_features(vdev);
 808
 809         features->index = 0;
 810         features->features = cpu_to_le32((u32)vdev->features);
 811         /* Write the first half of the feature bits to the host. */
 812         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 813         ccw->flags = 0;
 814         ccw->count = sizeof(*features);
 815         ccw->cda = (__u32)(unsigned long)features;
 816         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 817         if (ret)
 818                 goto out_free;
 819
 820         if (vcdev->revision == 0)
 821                 goto out_free;
 822
 823         features->index = 1;
 824         features->features = cpu_to_le32(vdev->features >> 32);
 825         /* Write the second half of the feature bits to the host. */
 826         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 827         ccw->flags = 0;
 828         ccw->count = sizeof(*features);
 829         ccw->cda = (__u32)(unsigned long)features;
 830         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 831
 832 out_free:
 833         kfree(features);
 834         kfree(ccw);
 835
 836         return ret;
 837 }
 838
 839 static void virtio_ccw_get_config(struct virtio_device *vdev,
 840                                   unsigned int offset, void *buf, unsigned len)
 841 {
 842         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 843         int ret;
 844         struct ccw1 *ccw;
 845         void *config_area;
 846         unsigned long flags;
 847
 848         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 849         if (!ccw)
 850                 return;
 851
 852         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 853         if (!config_area)
 854                 goto out_free;
 855
 856         /* Read the config area from the host. */
 857         ccw->cmd_code = CCW_CMD_READ_CONF;
 858         ccw->flags = 0;
 859         ccw->count = offset + len;
 860         ccw->cda = (__u32)(unsigned long)config_area;
 861         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 862         if (ret)
 863                 goto out_free;
 864
 865         spin_lock_irqsave(&vcdev->lock, flags);
 866         memcpy(vcdev->config, config_area, offset + len);
 867         if (vcdev->config_ready < offset + len)
 868                 vcdev->config_ready = offset + len;
 869         spin_unlock_irqrestore(&vcdev->lock, flags);
 870         if (buf)
 871                 memcpy(buf, config_area + offset, len);
 872
 873 out_free:
 874         kfree(config_area);
 875         kfree(ccw);
 876 }
 877
 878 static void virtio_ccw_set_config(struct virtio_device *vdev,
 879                                   unsigned int offset, const void *buf,
 880                                   unsigned len)
 881 {
 882         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 883         struct ccw1 *ccw;
 884         void *config_area;
 885         unsigned long flags;
 886
 887         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 888         if (!ccw)
 889                 return;
 890
 891         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 892         if (!config_area)
 893                 goto out_free;
 894
 895         /* Make sure we don't overwrite fields. */
 896         if (vcdev->config_ready < offset)
 897                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 898         spin_lock_irqsave(&vcdev->lock, flags);
 899         memcpy(&vcdev->config[offset], buf, len);
 900         /* Write the config area to the host. */
 901         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 902         spin_unlock_irqrestore(&vcdev->lock, flags);
 903         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 904         ccw->flags = 0;
 905         ccw->count = offset + len;
 906         ccw->cda = (__u32)(unsigned long)config_area;
 907         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 908
 909 out_free:
 910         kfree(config_area);
 911         kfree(ccw);
 912 }
 913
 914 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 915 {
 916         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 917
 918         return *vcdev->status;
 919 }
 920
 921 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 922 {
 923         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 924         u8 old_status = *vcdev->status;
 925         struct ccw1 *ccw;
 926         int ret;
 927
 928         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 929         if (!ccw)
 930                 return;
 931
 932         /* Write the status to the host. */
 933         *vcdev->status = status;
 934         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 935         ccw->flags = 0;
 936         ccw->count = sizeof(status);
 937         ccw->cda = (__u32)(unsigned long)vcdev->status;
 938         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 939         /* Write failed? We assume status is unchanged. */
 940         if (ret)
 941                 *vcdev->status = old_status;
 942         kfree(ccw);
 943 }
 944
 945 static struct virtio_config_ops virtio_ccw_config_ops = {
 946         .get_features = virtio_ccw_get_features,
 947         .finalize_features = virtio_ccw_finalize_features,
 948         .get = virtio_ccw_get_config,
 949         .set = virtio_ccw_set_config,
 950         .get_status = virtio_ccw_get_status,
 951         .set_status = virtio_ccw_set_status,
 952         .reset = virtio_ccw_reset,
 953         .find_vqs = virtio_ccw_find_vqs,
 954         .del_vqs = virtio_ccw_del_vqs,
 955 };
 956
 957
 958 /*
 959  * ccw bus driver related functions
 960  */
 961
 962 static void virtio_ccw_release_dev(struct device *_d)
 963 {
 964         struct virtio_device *dev = dev_to_virtio(_d);
 965         struct virtio_ccw_device *vcdev = to_vc_device(dev);
 966
 967         kfree(vcdev->status);
 968         kfree(vcdev->config_block);
 969         kfree(vcdev);
 970 }
 971
 972 static int irb_is_error(struct irb *irb)
 973 {
 974         if (scsw_cstat(&irb->scsw) != 0)
 975                 return 1;
 976         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
 977                 return 1;
 978         if (scsw_cc(&irb->scsw) != 0)
 979                 return 1;
 980         return 0;
 981 }
 982
 983 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
 984                                               int index)
 985 {
 986         struct virtio_ccw_vq_info *info;
 987         unsigned long flags;
 988         struct virtqueue *vq;
 989
 990         vq = NULL;
 991         spin_lock_irqsave(&vcdev->lock, flags);
 992         list_for_each_entry(info, &vcdev->virtqueues, node) {
 993                 if (info->vq->index == index) {
 994                         vq = info->vq;
 995                         break;
 996                 }
 997         }
 998         spin_unlock_irqrestore(&vcdev->lock, flags);
 999         return vq;
1000 }
1001
1002 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1003                                       __u32 activity)
1004 {
1005         if (vcdev->curr_io & activity) {
1006                 switch (activity) {
1007                 case VIRTIO_CCW_DOING_READ_FEAT:
1008                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1009                 case VIRTIO_CCW_DOING_READ_CONFIG:
1010                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1011                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1012                 case VIRTIO_CCW_DOING_SET_VQ:
1013                 case VIRTIO_CCW_DOING_SET_IND:
1014                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1015                 case VIRTIO_CCW_DOING_RESET:
1016                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1017                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1018                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1019                         vcdev->curr_io &= ~activity;
1020                         wake_up(&vcdev->wait_q);
1021                         break;
1022                 default:
1023                         /* don't know what to do... */
1024                         dev_warn(&vcdev->cdev->dev,
1025                                  "Suspicious activity '%08x'\n", activity);
1026                         WARN_ON(1);
1027                         break;
1028                 }
1029         }
1030 }
1031
1032 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1033                                    unsigned long intparm,
1034                                    struct irb *irb)
1035 {
1036         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1037         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1038         int i;
1039         struct virtqueue *vq;
1040
1041         if (!vcdev)
1042                 return;
1043         if (IS_ERR(irb)) {
1044                 vcdev->err = PTR_ERR(irb);
1045                 virtio_ccw_check_activity(vcdev, activity);
1046                 /* Don't poke around indicators, something's wrong. */
1047                 return;
1048         }
1049         /* Check if it's a notification from the host. */
1050         if ((intparm == 0) &&
1051             (scsw_stctl(&irb->scsw) ==
1052              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1053                 /* OK */
1054         }
1055         if (irb_is_error(irb)) {
1056                 /* Command reject? */
1057                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1058                     (irb->ecw[0] & SNS0_CMD_REJECT))
1059                         vcdev->err = -EOPNOTSUPP;
1060                 else
1061                         /* Map everything else to -EIO. */
1062                         vcdev->err = -EIO;
1063         }
1064         virtio_ccw_check_activity(vcdev, activity);
1065         for_each_set_bit(i, &vcdev->indicators,
1066                          sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1067                 /* The bit clear must happen before the vring kick. */
1068                 clear_bit(i, &vcdev->indicators);
1069                 barrier();
1070                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1071                 vring_interrupt(0, vq);
1072         }
1073         if (test_bit(0, &vcdev->indicators2)) {
1074                 virtio_config_changed(&vcdev->vdev);
1075                 clear_bit(0, &vcdev->indicators2);
1076         }
1077 }
1078
1079 /*
1080  * We usually want to autoonline all devices, but give the admin
1081  * a way to exempt devices from this.
1082  */
1083 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1084                      (8*sizeof(long)))
1085 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1086
1087 static char *no_auto = "";
1088
1089 module_param(no_auto, charp, 0444);
1090 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1091
1092 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1093 {
1094         struct ccw_dev_id id;
1095
1096         ccw_device_get_id(cdev, &id);
1097         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1098                 return 0;
1099         return 1;
1100 }
1101
1102 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1103 {
1104         struct ccw_device *cdev = data;
1105         int ret;
1106
1107         ret = ccw_device_set_online(cdev);
1108         if (ret)
1109                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1110 }
1111
1112 static int virtio_ccw_probe(struct ccw_device *cdev)
1113 {
1114         cdev->handler = virtio_ccw_int_handler;
1115
1116         if (virtio_ccw_check_autoonline(cdev))
1117                 async_schedule(virtio_ccw_auto_online, cdev);
1118         return 0;
1119 }
1120
1121 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1122 {
1123         unsigned long flags;
1124         struct virtio_ccw_device *vcdev;
1125
1126         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1127         vcdev = dev_get_drvdata(&cdev->dev);
1128         if (!vcdev || vcdev->going_away) {
1129                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1130                 return NULL;
1131         }
1132         vcdev->going_away = true;
1133         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1134         return vcdev;
1135 }
1136
1137 static void virtio_ccw_remove(struct ccw_device *cdev)
1138 {
1139         unsigned long flags;
1140         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1141
1142         if (vcdev && cdev->online) {
1143                 if (vcdev->device_lost)
1144                         virtio_break_device(&vcdev->vdev);
1145                 unregister_virtio_device(&vcdev->vdev);
1146                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1147                 dev_set_drvdata(&cdev->dev, NULL);
1148                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1149         }
1150         cdev->handler = NULL;
1151 }
1152
1153 static int virtio_ccw_offline(struct ccw_device *cdev)
1154 {
1155         unsigned long flags;
1156         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1157
1158         if (!vcdev)
1159                 return 0;
1160         if (vcdev->device_lost)
1161                 virtio_break_device(&vcdev->vdev);
1162         unregister_virtio_device(&vcdev->vdev);
1163         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1164         dev_set_drvdata(&cdev->dev, NULL);
1165         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1166         return 0;
1167 }
1168
1169 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1170 {
1171         struct virtio_rev_info *rev;
1172         struct ccw1 *ccw;
1173         int ret;
1174
1175         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1176         if (!ccw)
1177                 return -ENOMEM;
1178         rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1179         if (!rev) {
1180                 kfree(ccw);
1181                 return -ENOMEM;
1182         }
1183
1184         /* Set transport revision */
1185         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1186         ccw->flags = 0;
1187         ccw->count = sizeof(*rev);
1188         ccw->cda = (__u32)(unsigned long)rev;
1189
1190         vcdev->revision = VIRTIO_CCW_REV_MAX;
1191         do {
1192                 rev->revision = vcdev->revision;
1193                 /* none of our supported revisions carry payload */
1194                 rev->length = 0;
1195                 ret = ccw_io_helper(vcdev, ccw,
1196                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1197                 if (ret == -EOPNOTSUPP) {
1198                         if (vcdev->revision == 0)
1199                                 /*
1200                                  * The host device does not support setting
1201                                  * the revision: let's operate it in legacy
1202                                  * mode.
1203                                  */
1204                                 ret = 0;
1205                         else
1206                                 vcdev->revision--;
1207                 }
1208         } while (ret == -EOPNOTSUPP);
1209
1210         kfree(ccw);
1211         kfree(rev);
1212         return ret;
1213 }
1214
1215 static int virtio_ccw_online(struct ccw_device *cdev)
1216 {
1217         int ret;
1218         struct virtio_ccw_device *vcdev;
1219         unsigned long flags;
1220
1221         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1222         if (!vcdev) {
1223                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1224                 ret = -ENOMEM;
1225                 goto out_free;
1226         }
1227         vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1228                                    GFP_DMA | GFP_KERNEL);
1229         if (!vcdev->config_block) {
1230                 ret = -ENOMEM;
1231                 goto out_free;
1232         }
1233         vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1234         if (!vcdev->status) {
1235                 ret = -ENOMEM;
1236                 goto out_free;
1237         }
1238
1239         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1240
1241         vcdev->vdev.dev.parent = &cdev->dev;
1242         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1243         vcdev->vdev.config = &virtio_ccw_config_ops;
1244         vcdev->cdev = cdev;
1245         init_waitqueue_head(&vcdev->wait_q);
1246         INIT_LIST_HEAD(&vcdev->virtqueues);
1247         spin_lock_init(&vcdev->lock);
1248         mutex_init(&vcdev->io_lock);
1249
1250         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1251         dev_set_drvdata(&cdev->dev, vcdev);
1252         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1253         vcdev->vdev.id.vendor = cdev->id.cu_type;
1254         vcdev->vdev.id.device = cdev->id.cu_model;
1255
1256         ret = virtio_ccw_set_transport_rev(vcdev);
1257         if (ret)
1258                 goto out_free;
1259
1260         ret = register_virtio_device(&vcdev->vdev);
1261         if (ret) {
1262                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1263                          ret);
1264                 goto out_put;
1265         }
1266         return 0;
1267 out_put:
1268         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1269         dev_set_drvdata(&cdev->dev, NULL);
1270         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1271         put_device(&vcdev->vdev.dev);
1272         return ret;
1273 out_free:
1274         if (vcdev) {
1275                 kfree(vcdev->status);
1276                 kfree(vcdev->config_block);
1277         }
1278         kfree(vcdev);
1279         return ret;
1280 }
1281
1282 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1283 {
1284         int rc;
1285         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1286
1287         /*
1288          * Make sure vcdev is set
1289          * i.e. set_offline/remove callback not already running
1290          */
1291         if (!vcdev)
1292                 return NOTIFY_DONE;
1293
1294         switch (event) {
1295         case CIO_GONE:
1296                 vcdev->device_lost = true;
1297                 rc = NOTIFY_DONE;
1298                 break;
1299         default:
1300                 rc = NOTIFY_DONE;
1301                 break;
1302         }
1303         return rc;
1304 }
1305
1306 static struct ccw_device_id virtio_ids[] = {
1307         { CCW_DEVICE(0x3832, 0) },
1308         {},
1309 };
1310 MODULE_DEVICE_TABLE(ccw, virtio_ids);
1311
1312 static struct ccw_driver virtio_ccw_driver = {
1313         .driver = {
1314                 .owner = THIS_MODULE,
1315                 .name = "virtio_ccw",
1316         },
1317         .ids = virtio_ids,
1318         .probe = virtio_ccw_probe,
1319         .remove = virtio_ccw_remove,
1320         .set_offline = virtio_ccw_offline,
1321         .set_online = virtio_ccw_online,
1322         .notify = virtio_ccw_cio_notify,
1323         .int_class = IRQIO_VIR,
1324 };
1325
1326 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1327                            int max_digit, int max_val)
1328 {
1329         int diff;
1330
1331         diff = 0;
1332         *val = 0;
1333
1334         while (diff <= max_digit) {
1335                 int value = hex_to_bin(**cp);
1336
1337                 if (value < 0)
1338                         break;
1339                 *val = *val * 16 + value;
1340                 (*cp)++;
1341                 diff++;
1342         }
1343
1344         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1345                 return 1;
1346
1347         return 0;
1348 }
1349
1350 static int __init parse_busid(char *str, unsigned int *cssid,
1351                               unsigned int *ssid, unsigned int *devno)
1352 {
1353         char *str_work;
1354         int rc, ret;
1355
1356         rc = 1;
1357
1358         if (*str == '\0')
1359                 goto out;
1360
1361         str_work = str;
1362         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1363         if (ret || (str_work[0] != '.'))
1364                 goto out;
1365         str_work++;
1366         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1367         if (ret || (str_work[0] != '.'))
1368                 goto out;
1369         str_work++;
1370         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1371         if (ret || (str_work[0] != '\0'))
1372                 goto out;
1373
1374         rc = 0;
1375 out:
1376         return rc;
1377 }
1378
1379 static void __init no_auto_parse(void)
1380 {
1381         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1382         char *parm, *str;
1383         int rc;
1384
1385         str = no_auto;
1386         while ((parm = strsep(&str, ","))) {
1387                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1388                                  &from_ssid, &from);
1389                 if (rc)
1390                         continue;
1391                 if (parm != NULL) {
1392                         rc = parse_busid(parm, &to_cssid,
1393                                          &to_ssid, &to);
1394                         if ((from_ssid > to_ssid) ||
1395                             ((from_ssid == to_ssid) && (from > to)))
1396                                 rc = -EINVAL;
1397                 } else {
1398                         to_cssid = from_cssid;
1399                         to_ssid = from_ssid;
1400                         to = from;
1401                 }
1402                 if (rc)
1403                         continue;
1404                 while ((from_ssid < to_ssid) ||
1405                        ((from_ssid == to_ssid) && (from <= to))) {
1406                         set_bit(from, devs_no_auto[from_ssid]);
1407                         from++;
1408                         if (from > __MAX_SUBCHANNEL) {
1409                                 from_ssid++;
1410                                 from = 0;
1411                         }
1412                 }
1413         }
1414 }
1415
1416 static int __init virtio_ccw_init(void)
1417 {
1418         /* parse no_auto string before we do anything further */
1419         no_auto_parse();
1420         return ccw_driver_register(&virtio_ccw_driver);
1421 }
1422 module_init(virtio_ccw_init);
1423
1424 static void __exit virtio_ccw_exit(void)
1425 {
1426         int i;
1427
1428         ccw_driver_unregister(&virtio_ccw_driver);
1429         for (i = 0; i < MAX_AIRQ_AREAS; i++)
1430                 destroy_airq_info(airq_areas[i]);
1431 }
1432 module_exit(virtio_ccw_exit);