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