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