drivers/s390/virtio/virtio_ccw.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * ccw based virtio transport
   4  *
   5  * Copyright IBM Corp. 2012, 2014
   6  *
   7  *    Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
   8  */
   9
  10 #include <linux/kernel_stat.h>
  11 #include <linux/init.h>
  12 #include <linux/memblock.h>
  13 #include <linux/err.h>
  14 #include <linux/virtio.h>
  15 #include <linux/virtio_config.h>
  16 #include <linux/slab.h>
  17 #include <linux/interrupt.h>
  18 #include <linux/virtio_ring.h>
  19 #include <linux/pfn.h>
  20 #include <linux/async.h>
  21 #include <linux/wait.h>
  22 #include <linux/list.h>
  23 #include <linux/bitops.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/io.h>
  26 #include <linux/kvm_para.h>
  27 #include <linux/notifier.h>
  28 #include <asm/diag.h>
  29 #include <asm/setup.h>
  30 #include <asm/irq.h>
  31 #include <asm/cio.h>
  32 #include <asm/ccwdev.h>
  33 #include <asm/virtio-ccw.h>
  34 #include <asm/isc.h>
  35 #include <asm/airq.h>
  36
  37 /*
  38  * virtio related functions
  39  */
  40
  41 struct vq_config_block {
  42         __u16 index;
  43         __u16 num;
  44 } __packed;
  45
  46 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  47 /* same as PCI config space size, should be enough for all drivers */
  48
  49 struct virtio_ccw_device {
  50         struct virtio_device vdev;
  51         __u8 *status;
  52         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  53         struct ccw_device *cdev;
  54         __u32 curr_io;
  55         int err;
  56         unsigned int revision; /* Transport revision */
  57         wait_queue_head_t wait_q;
  58         spinlock_t lock;
  59         struct mutex io_lock; /* Serializes I/O requests */
  60         struct list_head virtqueues;
  61         unsigned long indicators;
  62         unsigned long indicators2;
  63         struct vq_config_block *config_block;
  64         bool is_thinint;
  65         bool going_away;
  66         bool device_lost;
  67         unsigned int config_ready;
  68         void *airq_info;
  69 };
  70
  71 struct vq_info_block_legacy {
  72         __u64 queue;
  73         __u32 align;
  74         __u16 index;
  75         __u16 num;
  76 } __packed;
  77
  78 struct vq_info_block {
  79         __u64 desc;
  80         __u32 res0;
  81         __u16 index;
  82         __u16 num;
  83         __u64 avail;
  84         __u64 used;
  85 } __packed;
  86
  87 struct virtio_feature_desc {
  88         __le32 features;
  89         __u8 index;
  90 } __packed;
  91
  92 struct virtio_thinint_area {
  93         unsigned long summary_indicator;
  94         unsigned long indicator;
  95         u64 bit_nr;
  96         u8 isc;
  97 } __packed;
  98
  99 struct virtio_rev_info {
 100         __u16 revision;
 101         __u16 length;
 102         __u8 data[];
 103 };
 104
 105 /* the highest virtio-ccw revision we support */
 106 #define VIRTIO_CCW_REV_MAX 1
 107
 108 struct virtio_ccw_vq_info {
 109         struct virtqueue *vq;
 110         int num;
 111         void *queue;
 112         union {
 113                 struct vq_info_block s;
 114                 struct vq_info_block_legacy l;
 115         } *info_block;
 116         int bit_nr;
 117         struct list_head node;
 118         long cookie;
 119 };
 120
 121 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 122
 123 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 124 #define MAX_AIRQ_AREAS 20
 125
 126 static int virtio_ccw_use_airq = 1;
 127
 128 struct airq_info {
 129         rwlock_t lock;
 130         u8 summary_indicator;
 131         struct airq_struct airq;
 132         struct airq_iv *aiv;
 133 };
 134 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 135
 136 #define CCW_CMD_SET_VQ 0x13
 137 #define CCW_CMD_VDEV_RESET 0x33
 138 #define CCW_CMD_SET_IND 0x43
 139 #define CCW_CMD_SET_CONF_IND 0x53
 140 #define CCW_CMD_READ_FEAT 0x12
 141 #define CCW_CMD_WRITE_FEAT 0x11
 142 #define CCW_CMD_READ_CONF 0x22
 143 #define CCW_CMD_WRITE_CONF 0x21
 144 #define CCW_CMD_WRITE_STATUS 0x31
 145 #define CCW_CMD_READ_VQ_CONF 0x32
 146 #define CCW_CMD_READ_STATUS 0x72
 147 #define CCW_CMD_SET_IND_ADAPTER 0x73
 148 #define CCW_CMD_SET_VIRTIO_REV 0x83
 149
 150 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 151 #define VIRTIO_CCW_DOING_RESET 0x00040000
 152 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 153 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 154 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 155 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 156 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 157 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 158 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 159 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 160 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 161 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 162 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 163 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 164
 165 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 166 {
 167         return container_of(vdev, struct virtio_ccw_device, vdev);
 168 }
 169
 170 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 171 {
 172         unsigned long i, flags;
 173
 174         write_lock_irqsave(&info->lock, flags);
 175         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 176                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 177                         airq_iv_free_bit(info->aiv, i);
 178                         airq_iv_set_ptr(info->aiv, i, 0);
 179                         break;
 180                 }
 181         }
 182         write_unlock_irqrestore(&info->lock, flags);
 183 }
 184
 185 static void virtio_airq_handler(struct airq_struct *airq)
 186 {
 187         struct airq_info *info = container_of(airq, struct airq_info, airq);
 188         unsigned long ai;
 189
 190         inc_irq_stat(IRQIO_VAI);
 191         read_lock(&info->lock);
 192         /* Walk through indicators field, summary indicator active. */
 193         for (ai = 0;;) {
 194                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 195                 if (ai == -1UL)
 196                         break;
 197                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 198         }
 199         info->summary_indicator = 0;
 200         smp_wmb();
 201         /* Walk through indicators field, summary indicator not active. */
 202         for (ai = 0;;) {
 203                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 204                 if (ai == -1UL)
 205                         break;
 206                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 207         }
 208         read_unlock(&info->lock);
 209 }
 210
 211 static struct airq_info *new_airq_info(void)
 212 {
 213         struct airq_info *info;
 214         int rc;
 215
 216         info = kzalloc(sizeof(*info), GFP_KERNEL);
 217         if (!info)
 218                 return NULL;
 219         rwlock_init(&info->lock);
 220         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
 221         if (!info->aiv) {
 222                 kfree(info);
 223                 return NULL;
 224         }
 225         info->airq.handler = virtio_airq_handler;
 226         info->airq.lsi_ptr = &info->summary_indicator;
 227         info->airq.lsi_mask = 0xff;
 228         info->airq.isc = VIRTIO_AIRQ_ISC;
 229         rc = register_adapter_interrupt(&info->airq);
 230         if (rc) {
 231                 airq_iv_release(info->aiv);
 232                 kfree(info);
 233                 return NULL;
 234         }
 235         return info;
 236 }
 237
 238 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 239                                         u64 *first, void **airq_info)
 240 {
 241         int i, j;
 242         struct airq_info *info;
 243         unsigned long indicator_addr = 0;
 244         unsigned long bit, flags;
 245
 246         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 247                 if (!airq_areas[i])
 248                         airq_areas[i] = new_airq_info();
 249                 info = airq_areas[i];
 250                 if (!info)
 251                         return 0;
 252                 write_lock_irqsave(&info->lock, flags);
 253                 bit = airq_iv_alloc(info->aiv, nvqs);
 254                 if (bit == -1UL) {
 255                         /* Not enough vacancies. */
 256                         write_unlock_irqrestore(&info->lock, flags);
 257                         continue;
 258                 }
 259                 *first = bit;
 260                 *airq_info = info;
 261                 indicator_addr = (unsigned long)info->aiv->vector;
 262                 for (j = 0; j < nvqs; j++) {
 263                         airq_iv_set_ptr(info->aiv, bit + j,
 264                                         (unsigned long)vqs[j]);
 265                 }
 266                 write_unlock_irqrestore(&info->lock, flags);
 267         }
 268         return indicator_addr;
 269 }
 270
 271 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 272 {
 273         struct virtio_ccw_vq_info *info;
 274
 275         if (!vcdev->airq_info)
 276                 return;
 277         list_for_each_entry(info, &vcdev->virtqueues, node)
 278                 drop_airq_indicator(info->vq, vcdev->airq_info);
 279 }
 280
 281 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 282 {
 283         unsigned long flags;
 284         __u32 ret;
 285
 286         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 287         if (vcdev->err)
 288                 ret = 0;
 289         else
 290                 ret = vcdev->curr_io & flag;
 291         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 292         return ret;
 293 }
 294
 295 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 296                          struct ccw1 *ccw, __u32 intparm)
 297 {
 298         int ret;
 299         unsigned long flags;
 300         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 301
 302         mutex_lock(&vcdev->io_lock);
 303         do {
 304                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 305                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 306                 if (!ret) {
 307                         if (!vcdev->curr_io)
 308                                 vcdev->err = 0;
 309                         vcdev->curr_io |= flag;
 310                 }
 311                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 312                 cpu_relax();
 313         } while (ret == -EBUSY);
 314         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 315         ret = ret ? ret : vcdev->err;
 316         mutex_unlock(&vcdev->io_lock);
 317         return ret;
 318 }
 319
 320 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 321                                       struct ccw1 *ccw)
 322 {
 323         int ret;
 324         unsigned long *indicatorp = NULL;
 325         struct virtio_thinint_area *thinint_area = NULL;
 326         struct airq_info *airq_info = vcdev->airq_info;
 327
 328         if (vcdev->is_thinint) {
 329                 thinint_area = kzalloc(sizeof(*thinint_area),
 330                                        GFP_DMA | GFP_KERNEL);
 331                 if (!thinint_area)
 332                         return;
 333                 thinint_area->summary_indicator =
 334                         (unsigned long) &airq_info->summary_indicator;
 335                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 336                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 337                 ccw->count = sizeof(*thinint_area);
 338                 ccw->cda = (__u32)(unsigned long) thinint_area;
 339         } else {
 340                 /* payload is the address of the indicators */
 341                 indicatorp = kmalloc(sizeof(&vcdev->indicators),
 342                                      GFP_DMA | GFP_KERNEL);
 343                 if (!indicatorp)
 344                         return;
 345                 *indicatorp = 0;
 346                 ccw->cmd_code = CCW_CMD_SET_IND;
 347                 ccw->count = sizeof(&vcdev->indicators);
 348                 ccw->cda = (__u32)(unsigned long) indicatorp;
 349         }
 350         /* Deregister indicators from host. */
 351         vcdev->indicators = 0;
 352         ccw->flags = 0;
 353         ret = ccw_io_helper(vcdev, ccw,
 354                             vcdev->is_thinint ?
 355                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 356                             VIRTIO_CCW_DOING_SET_IND);
 357         if (ret && (ret != -ENODEV))
 358                 dev_info(&vcdev->cdev->dev,
 359                          "Failed to deregister indicators (%d)\n", ret);
 360         else if (vcdev->is_thinint)
 361                 virtio_ccw_drop_indicators(vcdev);
 362         kfree(indicatorp);
 363         kfree(thinint_area);
 364 }
 365
 366 static inline long __do_kvm_notify(struct subchannel_id schid,
 367                                    unsigned long queue_index,
 368                                    long cookie)
 369 {
 370         register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 371         register struct subchannel_id __schid asm("2") = schid;
 372         register unsigned long __index asm("3") = queue_index;
 373         register long __rc asm("2");
 374         register long __cookie asm("4") = cookie;
 375
 376         asm volatile ("diag 2,4,0x500\n"
 377                       : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 378                       "d"(__cookie)
 379                       : "memory", "cc");
 380         return __rc;
 381 }
 382
 383 static inline long do_kvm_notify(struct subchannel_id schid,
 384                                  unsigned long queue_index,
 385                                  long cookie)
 386 {
 387         diag_stat_inc(DIAG_STAT_X500);
 388         return __do_kvm_notify(schid, queue_index, cookie);
 389 }
 390
 391 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 392 {
 393         struct virtio_ccw_vq_info *info = vq->priv;
 394         struct virtio_ccw_device *vcdev;
 395         struct subchannel_id schid;
 396
 397         vcdev = to_vc_device(info->vq->vdev);
 398         ccw_device_get_schid(vcdev->cdev, &schid);
 399         info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 400         if (info->cookie < 0)
 401                 return false;
 402         return true;
 403 }
 404
 405 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 406                                    struct ccw1 *ccw, int index)
 407 {
 408         int ret;
 409
 410         vcdev->config_block->index = index;
 411         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 412         ccw->flags = 0;
 413         ccw->count = sizeof(struct vq_config_block);
 414         ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
 415         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 416         if (ret)
 417                 return ret;
 418         return vcdev->config_block->num ?: -ENOENT;
 419 }
 420
 421 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 422 {
 423         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 424         struct virtio_ccw_vq_info *info = vq->priv;
 425         unsigned long flags;
 426         unsigned long size;
 427         int ret;
 428         unsigned int index = vq->index;
 429
 430         /* Remove from our list. */
 431         spin_lock_irqsave(&vcdev->lock, flags);
 432         list_del(&info->node);
 433         spin_unlock_irqrestore(&vcdev->lock, flags);
 434
 435         /* Release from host. */
 436         if (vcdev->revision == 0) {
 437                 info->info_block->l.queue = 0;
 438                 info->info_block->l.align = 0;
 439                 info->info_block->l.index = index;
 440                 info->info_block->l.num = 0;
 441                 ccw->count = sizeof(info->info_block->l);
 442         } else {
 443                 info->info_block->s.desc = 0;
 444                 info->info_block->s.index = index;
 445                 info->info_block->s.num = 0;
 446                 info->info_block->s.avail = 0;
 447                 info->info_block->s.used = 0;
 448                 ccw->count = sizeof(info->info_block->s);
 449         }
 450         ccw->cmd_code = CCW_CMD_SET_VQ;
 451         ccw->flags = 0;
 452         ccw->cda = (__u32)(unsigned long)(info->info_block);
 453         ret = ccw_io_helper(vcdev, ccw,
 454                             VIRTIO_CCW_DOING_SET_VQ | index);
 455         /*
 456          * -ENODEV isn't considered an error: The device is gone anyway.
 457          * This may happen on device detach.
 458          */
 459         if (ret && (ret != -ENODEV))
 460                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 461                          ret, index);
 462
 463         vring_del_virtqueue(vq);
 464         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 465         free_pages_exact(info->queue, size);
 466         kfree(info->info_block);
 467         kfree(info);
 468 }
 469
 470 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 471 {
 472         struct virtqueue *vq, *n;
 473         struct ccw1 *ccw;
 474         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 475
 476         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 477         if (!ccw)
 478                 return;
 479
 480         virtio_ccw_drop_indicator(vcdev, ccw);
 481
 482         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 483                 virtio_ccw_del_vq(vq, ccw);
 484
 485         kfree(ccw);
 486 }
 487
 488 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 489                                              int i, vq_callback_t *callback,
 490                                              const char *name, bool ctx,
 491                                              struct ccw1 *ccw)
 492 {
 493         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 494         int err;
 495         struct virtqueue *vq = NULL;
 496         struct virtio_ccw_vq_info *info;
 497         unsigned long size = 0; /* silence the compiler */
 498         unsigned long flags;
 499
 500         /* Allocate queue. */
 501         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 502         if (!info) {
 503                 dev_warn(&vcdev->cdev->dev, "no info\n");
 504                 err = -ENOMEM;
 505                 goto out_err;
 506         }
 507         info->info_block = kzalloc(sizeof(*info->info_block),
 508                                    GFP_DMA | GFP_KERNEL);
 509         if (!info->info_block) {
 510                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 511                 err = -ENOMEM;
 512                 goto out_err;
 513         }
 514         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 515         if (info->num < 0) {
 516                 err = info->num;
 517                 goto out_err;
 518         }
 519         size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
 520         info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
 521         if (info->queue == NULL) {
 522                 dev_warn(&vcdev->cdev->dev, "no queue\n");
 523                 err = -ENOMEM;
 524                 goto out_err;
 525         }
 526
 527         vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
 528                                  true, ctx, info->queue, virtio_ccw_kvm_notify,
 529                                  callback, name);
 530         if (!vq) {
 531                 /* For now, we fail if we can't get the requested size. */
 532                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 533                 err = -ENOMEM;
 534                 goto out_err;
 535         }
 536
 537         /* Register it with the host. */
 538         if (vcdev->revision == 0) {
 539                 info->info_block->l.queue = (__u64)info->queue;
 540                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 541                 info->info_block->l.index = i;
 542                 info->info_block->l.num = info->num;
 543                 ccw->count = sizeof(info->info_block->l);
 544         } else {
 545                 info->info_block->s.desc = (__u64)info->queue;
 546                 info->info_block->s.index = i;
 547                 info->info_block->s.num = info->num;
 548                 info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
 549                 info->info_block->s.used = (__u64)virtqueue_get_used(vq);
 550                 ccw->count = sizeof(info->info_block->s);
 551         }
 552         ccw->cmd_code = CCW_CMD_SET_VQ;
 553         ccw->flags = 0;
 554         ccw->cda = (__u32)(unsigned long)(info->info_block);
 555         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 556         if (err) {
 557                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 558                 goto out_err;
 559         }
 560
 561         info->vq = vq;
 562         vq->priv = info;
 563
 564         /* Save it to our list. */
 565         spin_lock_irqsave(&vcdev->lock, flags);
 566         list_add(&info->node, &vcdev->virtqueues);
 567         spin_unlock_irqrestore(&vcdev->lock, flags);
 568
 569         return vq;
 570
 571 out_err:
 572         if (vq)
 573                 vring_del_virtqueue(vq);
 574         if (info) {
 575                 if (info->queue)
 576                         free_pages_exact(info->queue, size);
 577                 kfree(info->info_block);
 578         }
 579         kfree(info);
 580         return ERR_PTR(err);
 581 }
 582
 583 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 584                                            struct virtqueue *vqs[], int nvqs,
 585                                            struct ccw1 *ccw)
 586 {
 587         int ret;
 588         struct virtio_thinint_area *thinint_area = NULL;
 589         struct airq_info *info;
 590
 591         thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
 592         if (!thinint_area) {
 593                 ret = -ENOMEM;
 594                 goto out;
 595         }
 596         /* Try to get an indicator. */
 597         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 598                                                      &thinint_area->bit_nr,
 599                                                      &vcdev->airq_info);
 600         if (!thinint_area->indicator) {
 601                 ret = -ENOSPC;
 602                 goto out;
 603         }
 604         info = vcdev->airq_info;
 605         thinint_area->summary_indicator =
 606                 (unsigned long) &info->summary_indicator;
 607         thinint_area->isc = VIRTIO_AIRQ_ISC;
 608         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 609         ccw->flags = CCW_FLAG_SLI;
 610         ccw->count = sizeof(*thinint_area);
 611         ccw->cda = (__u32)(unsigned long)thinint_area;
 612         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 613         if (ret) {
 614                 if (ret == -EOPNOTSUPP) {
 615                         /*
 616                          * The host does not support adapter interrupts
 617                          * for virtio-ccw, stop trying.
 618                          */
 619                         virtio_ccw_use_airq = 0;
 620                         pr_info("Adapter interrupts unsupported on host\n");
 621                 } else
 622                         dev_warn(&vcdev->cdev->dev,
 623                                  "enabling adapter interrupts = %d\n", ret);
 624                 virtio_ccw_drop_indicators(vcdev);
 625         }
 626 out:
 627         kfree(thinint_area);
 628         return ret;
 629 }
 630
 631 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 632                                struct virtqueue *vqs[],
 633                                vq_callback_t *callbacks[],
 634                                const char * const names[],
 635                                const bool *ctx,
 636                                struct irq_affinity *desc)
 637 {
 638         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 639         unsigned long *indicatorp = NULL;
 640         int ret, i, queue_idx = 0;
 641         struct ccw1 *ccw;
 642
 643         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 644         if (!ccw)
 645                 return -ENOMEM;
 646
 647         for (i = 0; i < nvqs; ++i) {
 648                 if (!names[i]) {
 649                         vqs[i] = NULL;
 650                         continue;
 651                 }
 652
 653                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 654                                              names[i], ctx ? ctx[i] : false,
 655                                              ccw);
 656                 if (IS_ERR(vqs[i])) {
 657                         ret = PTR_ERR(vqs[i]);
 658                         vqs[i] = NULL;
 659                         goto out;
 660                 }
 661         }
 662         ret = -ENOMEM;
 663         /*
 664          * We need a data area under 2G to communicate. Our payload is
 665          * the address of the indicators.
 666         */
 667         indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
 668         if (!indicatorp)
 669                 goto out;
 670         *indicatorp = (unsigned long) &vcdev->indicators;
 671         if (vcdev->is_thinint) {
 672                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 673                 if (ret)
 674                         /* no error, just fall back to legacy interrupts */
 675                         vcdev->is_thinint = false;
 676         }
 677         if (!vcdev->is_thinint) {
 678                 /* Register queue indicators with host. */
 679                 vcdev->indicators = 0;
 680                 ccw->cmd_code = CCW_CMD_SET_IND;
 681                 ccw->flags = 0;
 682                 ccw->count = sizeof(&vcdev->indicators);
 683                 ccw->cda = (__u32)(unsigned long) indicatorp;
 684                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 685                 if (ret)
 686                         goto out;
 687         }
 688         /* Register indicators2 with host for config changes */
 689         *indicatorp = (unsigned long) &vcdev->indicators2;
 690         vcdev->indicators2 = 0;
 691         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 692         ccw->flags = 0;
 693         ccw->count = sizeof(&vcdev->indicators2);
 694         ccw->cda = (__u32)(unsigned long) indicatorp;
 695         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 696         if (ret)
 697                 goto out;
 698
 699         kfree(indicatorp);
 700         kfree(ccw);
 701         return 0;
 702 out:
 703         kfree(indicatorp);
 704         kfree(ccw);
 705         virtio_ccw_del_vqs(vdev);
 706         return ret;
 707 }
 708
 709 static void virtio_ccw_reset(struct virtio_device *vdev)
 710 {
 711         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 712         struct ccw1 *ccw;
 713
 714         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 715         if (!ccw)
 716                 return;
 717
 718         /* Zero status bits. */
 719         *vcdev->status = 0;
 720
 721         /* Send a reset ccw on device. */
 722         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 723         ccw->flags = 0;
 724         ccw->count = 0;
 725         ccw->cda = 0;
 726         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 727         kfree(ccw);
 728 }
 729
 730 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 731 {
 732         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 733         struct virtio_feature_desc *features;
 734         int ret;
 735         u64 rc;
 736         struct ccw1 *ccw;
 737
 738         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 739         if (!ccw)
 740                 return 0;
 741
 742         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 743         if (!features) {
 744                 rc = 0;
 745                 goto out_free;
 746         }
 747         /* Read the feature bits from the host. */
 748         features->index = 0;
 749         ccw->cmd_code = CCW_CMD_READ_FEAT;
 750         ccw->flags = 0;
 751         ccw->count = sizeof(*features);
 752         ccw->cda = (__u32)(unsigned long)features;
 753         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 754         if (ret) {
 755                 rc = 0;
 756                 goto out_free;
 757         }
 758
 759         rc = le32_to_cpu(features->features);
 760
 761         if (vcdev->revision == 0)
 762                 goto out_free;
 763
 764         /* Read second half of the feature bits from the host. */
 765         features->index = 1;
 766         ccw->cmd_code = CCW_CMD_READ_FEAT;
 767         ccw->flags = 0;
 768         ccw->count = sizeof(*features);
 769         ccw->cda = (__u32)(unsigned long)features;
 770         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 771         if (ret == 0)
 772                 rc |= (u64)le32_to_cpu(features->features) << 32;
 773
 774 out_free:
 775         kfree(features);
 776         kfree(ccw);
 777         return rc;
 778 }
 779
 780 static void ccw_transport_features(struct virtio_device *vdev)
 781 {
 782         /*
 783          * Packed ring isn't enabled on virtio_ccw for now,
 784          * because virtio_ccw uses some legacy accessors,
 785          * e.g. virtqueue_get_avail() and virtqueue_get_used()
 786          * which aren't available in packed ring currently.
 787          */
 788         __virtio_clear_bit(vdev, VIRTIO_F_RING_PACKED);
 789 }
 790
 791 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 792 {
 793         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 794         struct virtio_feature_desc *features;
 795         struct ccw1 *ccw;
 796         int ret;
 797
 798         if (vcdev->revision >= 1 &&
 799             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 800                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 801                         "but does not have VIRTIO_F_VERSION_1\n");
 802                 return -EINVAL;
 803         }
 804
 805         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 806         if (!ccw)
 807                 return -ENOMEM;
 808
 809         features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
 810         if (!features) {
 811                 ret = -ENOMEM;
 812                 goto out_free;
 813         }
 814         /* Give virtio_ring a chance to accept features. */
 815         vring_transport_features(vdev);
 816
 817         /* Give virtio_ccw a chance to accept features. */
 818         ccw_transport_features(vdev);
 819
 820         features->index = 0;
 821         features->features = cpu_to_le32((u32)vdev->features);
 822         /* Write the first half of the feature bits to the host. */
 823         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 824         ccw->flags = 0;
 825         ccw->count = sizeof(*features);
 826         ccw->cda = (__u32)(unsigned long)features;
 827         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 828         if (ret)
 829                 goto out_free;
 830
 831         if (vcdev->revision == 0)
 832                 goto out_free;
 833
 834         features->index = 1;
 835         features->features = cpu_to_le32(vdev->features >> 32);
 836         /* Write the second half of the feature bits to the host. */
 837         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 838         ccw->flags = 0;
 839         ccw->count = sizeof(*features);
 840         ccw->cda = (__u32)(unsigned long)features;
 841         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 842
 843 out_free:
 844         kfree(features);
 845         kfree(ccw);
 846
 847         return ret;
 848 }
 849
 850 static void virtio_ccw_get_config(struct virtio_device *vdev,
 851                                   unsigned int offset, void *buf, unsigned len)
 852 {
 853         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 854         int ret;
 855         struct ccw1 *ccw;
 856         void *config_area;
 857         unsigned long flags;
 858
 859         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 860         if (!ccw)
 861                 return;
 862
 863         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 864         if (!config_area)
 865                 goto out_free;
 866
 867         /* Read the config area from the host. */
 868         ccw->cmd_code = CCW_CMD_READ_CONF;
 869         ccw->flags = 0;
 870         ccw->count = offset + len;
 871         ccw->cda = (__u32)(unsigned long)config_area;
 872         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 873         if (ret)
 874                 goto out_free;
 875
 876         spin_lock_irqsave(&vcdev->lock, flags);
 877         memcpy(vcdev->config, config_area, offset + len);
 878         if (vcdev->config_ready < offset + len)
 879                 vcdev->config_ready = offset + len;
 880         spin_unlock_irqrestore(&vcdev->lock, flags);
 881         if (buf)
 882                 memcpy(buf, config_area + offset, len);
 883
 884 out_free:
 885         kfree(config_area);
 886         kfree(ccw);
 887 }
 888
 889 static void virtio_ccw_set_config(struct virtio_device *vdev,
 890                                   unsigned int offset, const void *buf,
 891                                   unsigned len)
 892 {
 893         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 894         struct ccw1 *ccw;
 895         void *config_area;
 896         unsigned long flags;
 897
 898         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 899         if (!ccw)
 900                 return;
 901
 902         config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
 903         if (!config_area)
 904                 goto out_free;
 905
 906         /* Make sure we don't overwrite fields. */
 907         if (vcdev->config_ready < offset)
 908                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 909         spin_lock_irqsave(&vcdev->lock, flags);
 910         memcpy(&vcdev->config[offset], buf, len);
 911         /* Write the config area to the host. */
 912         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 913         spin_unlock_irqrestore(&vcdev->lock, flags);
 914         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 915         ccw->flags = 0;
 916         ccw->count = offset + len;
 917         ccw->cda = (__u32)(unsigned long)config_area;
 918         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 919
 920 out_free:
 921         kfree(config_area);
 922         kfree(ccw);
 923 }
 924
 925 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 926 {
 927         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 928         u8 old_status = *vcdev->status;
 929         struct ccw1 *ccw;
 930
 931         if (vcdev->revision < 1)
 932                 return *vcdev->status;
 933
 934         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 935         if (!ccw)
 936                 return old_status;
 937
 938         ccw->cmd_code = CCW_CMD_READ_STATUS;
 939         ccw->flags = 0;
 940         ccw->count = sizeof(*vcdev->status);
 941         ccw->cda = (__u32)(unsigned long)vcdev->status;
 942         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 943 /*
 944  * If the channel program failed (should only happen if the device
 945  * was hotunplugged, and then we clean up via the machine check
 946  * handler anyway), vcdev->status was not overwritten and we just
 947  * return the old status, which is fine.
 948 */
 949         kfree(ccw);
 950
 951         return *vcdev->status;
 952 }
 953
 954 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 955 {
 956         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 957         u8 old_status = *vcdev->status;
 958         struct ccw1 *ccw;
 959         int ret;
 960
 961         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
 962         if (!ccw)
 963                 return;
 964
 965         /* Write the status to the host. */
 966         *vcdev->status = status;
 967         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 968         ccw->flags = 0;
 969         ccw->count = sizeof(status);
 970         ccw->cda = (__u32)(unsigned long)vcdev->status;
 971         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 972         /* Write failed? We assume status is unchanged. */
 973         if (ret)
 974                 *vcdev->status = old_status;
 975         kfree(ccw);
 976 }
 977
 978 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 979 {
 980         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 981
 982         return dev_name(&vcdev->cdev->dev);
 983 }
 984
 985 static const struct virtio_config_ops virtio_ccw_config_ops = {
 986         .get_features = virtio_ccw_get_features,
 987         .finalize_features = virtio_ccw_finalize_features,
 988         .get = virtio_ccw_get_config,
 989         .set = virtio_ccw_set_config,
 990         .get_status = virtio_ccw_get_status,
 991         .set_status = virtio_ccw_set_status,
 992         .reset = virtio_ccw_reset,
 993         .find_vqs = virtio_ccw_find_vqs,
 994         .del_vqs = virtio_ccw_del_vqs,
 995         .bus_name = virtio_ccw_bus_name,
 996 };
 997
 998
 999 /*
1000  * ccw bus driver related functions
1001  */
1002
1003 static void virtio_ccw_release_dev(struct device *_d)
1004 {
1005         struct virtio_device *dev = dev_to_virtio(_d);
1006         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1007
1008         kfree(vcdev->status);
1009         kfree(vcdev->config_block);
1010         kfree(vcdev);
1011 }
1012
1013 static int irb_is_error(struct irb *irb)
1014 {
1015         if (scsw_cstat(&irb->scsw) != 0)
1016                 return 1;
1017         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1018                 return 1;
1019         if (scsw_cc(&irb->scsw) != 0)
1020                 return 1;
1021         return 0;
1022 }
1023
1024 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1025                                               int index)
1026 {
1027         struct virtio_ccw_vq_info *info;
1028         unsigned long flags;
1029         struct virtqueue *vq;
1030
1031         vq = NULL;
1032         spin_lock_irqsave(&vcdev->lock, flags);
1033         list_for_each_entry(info, &vcdev->virtqueues, node) {
1034                 if (info->vq->index == index) {
1035                         vq = info->vq;
1036                         break;
1037                 }
1038         }
1039         spin_unlock_irqrestore(&vcdev->lock, flags);
1040         return vq;
1041 }
1042
1043 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1044                                       __u32 activity)
1045 {
1046         if (vcdev->curr_io & activity) {
1047                 switch (activity) {
1048                 case VIRTIO_CCW_DOING_READ_FEAT:
1049                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1050                 case VIRTIO_CCW_DOING_READ_CONFIG:
1051                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1052                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1053                 case VIRTIO_CCW_DOING_READ_STATUS:
1054                 case VIRTIO_CCW_DOING_SET_VQ:
1055                 case VIRTIO_CCW_DOING_SET_IND:
1056                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1057                 case VIRTIO_CCW_DOING_RESET:
1058                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1059                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1060                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1061                         vcdev->curr_io &= ~activity;
1062                         wake_up(&vcdev->wait_q);
1063                         break;
1064                 default:
1065                         /* don't know what to do... */
1066                         dev_warn(&vcdev->cdev->dev,
1067                                  "Suspicious activity '%08x'\n", activity);
1068                         WARN_ON(1);
1069                         break;
1070                 }
1071         }
1072 }
1073
1074 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1075                                    unsigned long intparm,
1076                                    struct irb *irb)
1077 {
1078         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1079         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1080         int i;
1081         struct virtqueue *vq;
1082
1083         if (!vcdev)
1084                 return;
1085         if (IS_ERR(irb)) {
1086                 vcdev->err = PTR_ERR(irb);
1087                 virtio_ccw_check_activity(vcdev, activity);
1088                 /* Don't poke around indicators, something's wrong. */
1089                 return;
1090         }
1091         /* Check if it's a notification from the host. */
1092         if ((intparm == 0) &&
1093             (scsw_stctl(&irb->scsw) ==
1094              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1095                 /* OK */
1096         }
1097         if (irb_is_error(irb)) {
1098                 /* Command reject? */
1099                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1100                     (irb->ecw[0] & SNS0_CMD_REJECT))
1101                         vcdev->err = -EOPNOTSUPP;
1102                 else
1103                         /* Map everything else to -EIO. */
1104                         vcdev->err = -EIO;
1105         }
1106         virtio_ccw_check_activity(vcdev, activity);
1107         for_each_set_bit(i, &vcdev->indicators,
1108                          sizeof(vcdev->indicators) * BITS_PER_BYTE) {
1109                 /* The bit clear must happen before the vring kick. */
1110                 clear_bit(i, &vcdev->indicators);
1111                 barrier();
1112                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1113                 vring_interrupt(0, vq);
1114         }
1115         if (test_bit(0, &vcdev->indicators2)) {
1116                 virtio_config_changed(&vcdev->vdev);
1117                 clear_bit(0, &vcdev->indicators2);
1118         }
1119 }
1120
1121 /*
1122  * We usually want to autoonline all devices, but give the admin
1123  * a way to exempt devices from this.
1124  */
1125 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1126                      (8*sizeof(long)))
1127 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1128
1129 static char *no_auto = "";
1130
1131 module_param(no_auto, charp, 0444);
1132 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1133
1134 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1135 {
1136         struct ccw_dev_id id;
1137
1138         ccw_device_get_id(cdev, &id);
1139         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1140                 return 0;
1141         return 1;
1142 }
1143
1144 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1145 {
1146         struct ccw_device *cdev = data;
1147         int ret;
1148
1149         ret = ccw_device_set_online(cdev);
1150         if (ret)
1151                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1152 }
1153
1154 static int virtio_ccw_probe(struct ccw_device *cdev)
1155 {
1156         cdev->handler = virtio_ccw_int_handler;
1157
1158         if (virtio_ccw_check_autoonline(cdev))
1159                 async_schedule(virtio_ccw_auto_online, cdev);
1160         return 0;
1161 }
1162
1163 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1164 {
1165         unsigned long flags;
1166         struct virtio_ccw_device *vcdev;
1167
1168         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1169         vcdev = dev_get_drvdata(&cdev->dev);
1170         if (!vcdev || vcdev->going_away) {
1171                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1172                 return NULL;
1173         }
1174         vcdev->going_away = true;
1175         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1176         return vcdev;
1177 }
1178
1179 static void virtio_ccw_remove(struct ccw_device *cdev)
1180 {
1181         unsigned long flags;
1182         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1183
1184         if (vcdev && cdev->online) {
1185                 if (vcdev->device_lost)
1186                         virtio_break_device(&vcdev->vdev);
1187                 unregister_virtio_device(&vcdev->vdev);
1188                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1189                 dev_set_drvdata(&cdev->dev, NULL);
1190                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1191         }
1192         cdev->handler = NULL;
1193 }
1194
1195 static int virtio_ccw_offline(struct ccw_device *cdev)
1196 {
1197         unsigned long flags;
1198         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1199
1200         if (!vcdev)
1201                 return 0;
1202         if (vcdev->device_lost)
1203                 virtio_break_device(&vcdev->vdev);
1204         unregister_virtio_device(&vcdev->vdev);
1205         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1206         dev_set_drvdata(&cdev->dev, NULL);
1207         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1208         return 0;
1209 }
1210
1211 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1212 {
1213         struct virtio_rev_info *rev;
1214         struct ccw1 *ccw;
1215         int ret;
1216
1217         ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
1218         if (!ccw)
1219                 return -ENOMEM;
1220         rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
1221         if (!rev) {
1222                 kfree(ccw);
1223                 return -ENOMEM;
1224         }
1225
1226         /* Set transport revision */
1227         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1228         ccw->flags = 0;
1229         ccw->count = sizeof(*rev);
1230         ccw->cda = (__u32)(unsigned long)rev;
1231
1232         vcdev->revision = VIRTIO_CCW_REV_MAX;
1233         do {
1234                 rev->revision = vcdev->revision;
1235                 /* none of our supported revisions carry payload */
1236                 rev->length = 0;
1237                 ret = ccw_io_helper(vcdev, ccw,
1238                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1239                 if (ret == -EOPNOTSUPP) {
1240                         if (vcdev->revision == 0)
1241                                 /*
1242                                  * The host device does not support setting
1243                                  * the revision: let's operate it in legacy
1244                                  * mode.
1245                                  */
1246                                 ret = 0;
1247                         else
1248                                 vcdev->revision--;
1249                 }
1250         } while (ret == -EOPNOTSUPP);
1251
1252         kfree(ccw);
1253         kfree(rev);
1254         return ret;
1255 }
1256
1257 static int virtio_ccw_online(struct ccw_device *cdev)
1258 {
1259         int ret;
1260         struct virtio_ccw_device *vcdev;
1261         unsigned long flags;
1262
1263         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1264         if (!vcdev) {
1265                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1266                 ret = -ENOMEM;
1267                 goto out_free;
1268         }
1269         vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
1270                                    GFP_DMA | GFP_KERNEL);
1271         if (!vcdev->config_block) {
1272                 ret = -ENOMEM;
1273                 goto out_free;
1274         }
1275         vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
1276         if (!vcdev->status) {
1277                 ret = -ENOMEM;
1278                 goto out_free;
1279         }
1280
1281         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1282
1283         vcdev->vdev.dev.parent = &cdev->dev;
1284         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1285         vcdev->vdev.config = &virtio_ccw_config_ops;
1286         vcdev->cdev = cdev;
1287         init_waitqueue_head(&vcdev->wait_q);
1288         INIT_LIST_HEAD(&vcdev->virtqueues);
1289         spin_lock_init(&vcdev->lock);
1290         mutex_init(&vcdev->io_lock);
1291
1292         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1293         dev_set_drvdata(&cdev->dev, vcdev);
1294         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1295         vcdev->vdev.id.vendor = cdev->id.cu_type;
1296         vcdev->vdev.id.device = cdev->id.cu_model;
1297
1298         ret = virtio_ccw_set_transport_rev(vcdev);
1299         if (ret)
1300                 goto out_free;
1301
1302         ret = register_virtio_device(&vcdev->vdev);
1303         if (ret) {
1304                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1305                          ret);
1306                 goto out_put;
1307         }
1308         return 0;
1309 out_put:
1310         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1311         dev_set_drvdata(&cdev->dev, NULL);
1312         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1313         put_device(&vcdev->vdev.dev);
1314         return ret;
1315 out_free:
1316         if (vcdev) {
1317                 kfree(vcdev->status);
1318                 kfree(vcdev->config_block);
1319         }
1320         kfree(vcdev);
1321         return ret;
1322 }
1323
1324 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1325 {
1326         int rc;
1327         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1328
1329         /*
1330          * Make sure vcdev is set
1331          * i.e. set_offline/remove callback not already running
1332          */
1333         if (!vcdev)
1334                 return NOTIFY_DONE;
1335
1336         switch (event) {
1337         case CIO_GONE:
1338                 vcdev->device_lost = true;
1339                 rc = NOTIFY_DONE;
1340                 break;
1341         case CIO_OPER:
1342                 rc = NOTIFY_OK;
1343                 break;
1344         default:
1345                 rc = NOTIFY_DONE;
1346                 break;
1347         }
1348         return rc;
1349 }
1350
1351 static struct ccw_device_id virtio_ids[] = {
1352         { CCW_DEVICE(0x3832, 0) },
1353         {},
1354 };
1355
1356 #ifdef CONFIG_PM_SLEEP
1357 static int virtio_ccw_freeze(struct ccw_device *cdev)
1358 {
1359         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1360
1361         return virtio_device_freeze(&vcdev->vdev);
1362 }
1363
1364 static int virtio_ccw_restore(struct ccw_device *cdev)
1365 {
1366         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1367         int ret;
1368
1369         ret = virtio_ccw_set_transport_rev(vcdev);
1370         if (ret)
1371                 return ret;
1372
1373         return virtio_device_restore(&vcdev->vdev);
1374 }
1375 #endif
1376
1377 static struct ccw_driver virtio_ccw_driver = {
1378         .driver = {
1379                 .owner = THIS_MODULE,
1380                 .name = "virtio_ccw",
1381         },
1382         .ids = virtio_ids,
1383         .probe = virtio_ccw_probe,
1384         .remove = virtio_ccw_remove,
1385         .set_offline = virtio_ccw_offline,
1386         .set_online = virtio_ccw_online,
1387         .notify = virtio_ccw_cio_notify,
1388         .int_class = IRQIO_VIR,
1389 #ifdef CONFIG_PM_SLEEP
1390         .freeze = virtio_ccw_freeze,
1391         .thaw = virtio_ccw_restore,
1392         .restore = virtio_ccw_restore,
1393 #endif
1394 };
1395
1396 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1397                            int max_digit, int max_val)
1398 {
1399         int diff;
1400
1401         diff = 0;
1402         *val = 0;
1403
1404         while (diff <= max_digit) {
1405                 int value = hex_to_bin(**cp);
1406
1407                 if (value < 0)
1408                         break;
1409                 *val = *val * 16 + value;
1410                 (*cp)++;
1411                 diff++;
1412         }
1413
1414         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1415                 return 1;
1416
1417         return 0;
1418 }
1419
1420 static int __init parse_busid(char *str, unsigned int *cssid,
1421                               unsigned int *ssid, unsigned int *devno)
1422 {
1423         char *str_work;
1424         int rc, ret;
1425
1426         rc = 1;
1427
1428         if (*str == '\0')
1429                 goto out;
1430
1431         str_work = str;
1432         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1433         if (ret || (str_work[0] != '.'))
1434                 goto out;
1435         str_work++;
1436         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1437         if (ret || (str_work[0] != '.'))
1438                 goto out;
1439         str_work++;
1440         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1441         if (ret || (str_work[0] != '\0'))
1442                 goto out;
1443
1444         rc = 0;
1445 out:
1446         return rc;
1447 }
1448
1449 static void __init no_auto_parse(void)
1450 {
1451         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1452         char *parm, *str;
1453         int rc;
1454
1455         str = no_auto;
1456         while ((parm = strsep(&str, ","))) {
1457                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1458                                  &from_ssid, &from);
1459                 if (rc)
1460                         continue;
1461                 if (parm != NULL) {
1462                         rc = parse_busid(parm, &to_cssid,
1463                                          &to_ssid, &to);
1464                         if ((from_ssid > to_ssid) ||
1465                             ((from_ssid == to_ssid) && (from > to)))
1466                                 rc = -EINVAL;
1467                 } else {
1468                         to_cssid = from_cssid;
1469                         to_ssid = from_ssid;
1470                         to = from;
1471                 }
1472                 if (rc)
1473                         continue;
1474                 while ((from_ssid < to_ssid) ||
1475                        ((from_ssid == to_ssid) && (from <= to))) {
1476                         set_bit(from, devs_no_auto[from_ssid]);
1477                         from++;
1478                         if (from > __MAX_SUBCHANNEL) {
1479                                 from_ssid++;
1480                                 from = 0;
1481                         }
1482                 }
1483         }
1484 }
1485
1486 static int __init virtio_ccw_init(void)
1487 {
1488         /* parse no_auto string before we do anything further */
1489         no_auto_parse();
1490         return ccw_driver_register(&virtio_ccw_driver);
1491 }
1492 device_initcall(virtio_ccw_init);