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 vcdev_dma_area {
  50         unsigned long indicators;
  51         unsigned long indicators2;
  52         struct vq_config_block config_block;
  53         __u8 status;
  54 };
  55
  56 struct virtio_ccw_device {
  57         struct virtio_device vdev;
  58         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  59         struct ccw_device *cdev;
  60         __u32 curr_io;
  61         int err;
  62         unsigned int revision; /* Transport revision */
  63         wait_queue_head_t wait_q;
  64         spinlock_t lock;
  65         rwlock_t irq_lock;
  66         struct mutex io_lock; /* Serializes I/O requests */
  67         struct list_head virtqueues;
  68         bool is_thinint;
  69         bool going_away;
  70         bool device_lost;
  71         unsigned int config_ready;
  72         void *airq_info;
  73         struct vcdev_dma_area *dma_area;
  74 };
  75
  76 static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  77 {
  78         return &vcdev->dma_area->indicators;
  79 }
  80
  81 static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  82 {
  83         return &vcdev->dma_area->indicators2;
  84 }
  85
  86 struct vq_info_block_legacy {
  87         __u64 queue;
  88         __u32 align;
  89         __u16 index;
  90         __u16 num;
  91 } __packed;
  92
  93 struct vq_info_block {
  94         __u64 desc;
  95         __u32 res0;
  96         __u16 index;
  97         __u16 num;
  98         __u64 avail;
  99         __u64 used;
 100 } __packed;
 101
 102 struct virtio_feature_desc {
 103         __le32 features;
 104         __u8 index;
 105 } __packed;
 106
 107 struct virtio_thinint_area {
 108         unsigned long summary_indicator;
 109         unsigned long indicator;
 110         u64 bit_nr;
 111         u8 isc;
 112 } __packed;
 113
 114 struct virtio_rev_info {
 115         __u16 revision;
 116         __u16 length;
 117         __u8 data[];
 118 };
 119
 120 /* the highest virtio-ccw revision we support */
 121 #define VIRTIO_CCW_REV_MAX 2
 122
 123 struct virtio_ccw_vq_info {
 124         struct virtqueue *vq;
 125         int num;
 126         union {
 127                 struct vq_info_block s;
 128                 struct vq_info_block_legacy l;
 129         } *info_block;
 130         int bit_nr;
 131         struct list_head node;
 132         long cookie;
 133 };
 134
 135 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 136
 137 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 138 #define MAX_AIRQ_AREAS 20
 139
 140 static int virtio_ccw_use_airq = 1;
 141
 142 struct airq_info {
 143         rwlock_t lock;
 144         u8 summary_indicator_idx;
 145         struct airq_struct airq;
 146         struct airq_iv *aiv;
 147 };
 148 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 149 static DEFINE_MUTEX(airq_areas_lock);
 150
 151 static u8 *summary_indicators;
 152
 153 static inline u8 *get_summary_indicator(struct airq_info *info)
 154 {
 155         return summary_indicators + info->summary_indicator_idx;
 156 }
 157
 158 #define CCW_CMD_SET_VQ 0x13
 159 #define CCW_CMD_VDEV_RESET 0x33
 160 #define CCW_CMD_SET_IND 0x43
 161 #define CCW_CMD_SET_CONF_IND 0x53
 162 #define CCW_CMD_READ_FEAT 0x12
 163 #define CCW_CMD_WRITE_FEAT 0x11
 164 #define CCW_CMD_READ_CONF 0x22
 165 #define CCW_CMD_WRITE_CONF 0x21
 166 #define CCW_CMD_WRITE_STATUS 0x31
 167 #define CCW_CMD_READ_VQ_CONF 0x32
 168 #define CCW_CMD_READ_STATUS 0x72
 169 #define CCW_CMD_SET_IND_ADAPTER 0x73
 170 #define CCW_CMD_SET_VIRTIO_REV 0x83
 171
 172 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 173 #define VIRTIO_CCW_DOING_RESET 0x00040000
 174 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 175 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 176 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 177 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 178 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 179 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 180 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 181 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 182 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 183 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 184 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 185 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 186
 187 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 188 {
 189         return container_of(vdev, struct virtio_ccw_device, vdev);
 190 }
 191
 192 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 193 {
 194         unsigned long i, flags;
 195
 196         write_lock_irqsave(&info->lock, flags);
 197         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 198                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 199                         airq_iv_free_bit(info->aiv, i);
 200                         airq_iv_set_ptr(info->aiv, i, 0);
 201                         break;
 202                 }
 203         }
 204         write_unlock_irqrestore(&info->lock, flags);
 205 }
 206
 207 static void virtio_airq_handler(struct airq_struct *airq, bool floating)
 208 {
 209         struct airq_info *info = container_of(airq, struct airq_info, airq);
 210         unsigned long ai;
 211
 212         inc_irq_stat(IRQIO_VAI);
 213         read_lock(&info->lock);
 214         /* Walk through indicators field, summary indicator active. */
 215         for (ai = 0;;) {
 216                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 217                 if (ai == -1UL)
 218                         break;
 219                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 220         }
 221         *(get_summary_indicator(info)) = 0;
 222         smp_wmb();
 223         /* Walk through indicators field, summary indicator not active. */
 224         for (ai = 0;;) {
 225                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 226                 if (ai == -1UL)
 227                         break;
 228                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 229         }
 230         read_unlock(&info->lock);
 231 }
 232
 233 static struct airq_info *new_airq_info(int index)
 234 {
 235         struct airq_info *info;
 236         int rc;
 237
 238         info = kzalloc(sizeof(*info), GFP_KERNEL);
 239         if (!info)
 240                 return NULL;
 241         rwlock_init(&info->lock);
 242         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 243                                    | AIRQ_IV_CACHELINE);
 244         if (!info->aiv) {
 245                 kfree(info);
 246                 return NULL;
 247         }
 248         info->airq.handler = virtio_airq_handler;
 249         info->summary_indicator_idx = index;
 250         info->airq.lsi_ptr = get_summary_indicator(info);
 251         info->airq.lsi_mask = 0xff;
 252         info->airq.isc = VIRTIO_AIRQ_ISC;
 253         rc = register_adapter_interrupt(&info->airq);
 254         if (rc) {
 255                 airq_iv_release(info->aiv);
 256                 kfree(info);
 257                 return NULL;
 258         }
 259         return info;
 260 }
 261
 262 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 263                                         u64 *first, void **airq_info)
 264 {
 265         int i, j;
 266         struct airq_info *info;
 267         unsigned long indicator_addr = 0;
 268         unsigned long bit, flags;
 269
 270         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 271                 mutex_lock(&airq_areas_lock);
 272                 if (!airq_areas[i])
 273                         airq_areas[i] = new_airq_info(i);
 274                 info = airq_areas[i];
 275                 mutex_unlock(&airq_areas_lock);
 276                 if (!info)
 277                         return 0;
 278                 write_lock_irqsave(&info->lock, flags);
 279                 bit = airq_iv_alloc(info->aiv, nvqs);
 280                 if (bit == -1UL) {
 281                         /* Not enough vacancies. */
 282                         write_unlock_irqrestore(&info->lock, flags);
 283                         continue;
 284                 }
 285                 *first = bit;
 286                 *airq_info = info;
 287                 indicator_addr = (unsigned long)info->aiv->vector;
 288                 for (j = 0; j < nvqs; j++) {
 289                         airq_iv_set_ptr(info->aiv, bit + j,
 290                                         (unsigned long)vqs[j]);
 291                 }
 292                 write_unlock_irqrestore(&info->lock, flags);
 293         }
 294         return indicator_addr;
 295 }
 296
 297 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 298 {
 299         struct virtio_ccw_vq_info *info;
 300
 301         if (!vcdev->airq_info)
 302                 return;
 303         list_for_each_entry(info, &vcdev->virtqueues, node)
 304                 drop_airq_indicator(info->vq, vcdev->airq_info);
 305 }
 306
 307 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 308 {
 309         unsigned long flags;
 310         __u32 ret;
 311
 312         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 313         if (vcdev->err)
 314                 ret = 0;
 315         else
 316                 ret = vcdev->curr_io & flag;
 317         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 318         return ret;
 319 }
 320
 321 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 322                          struct ccw1 *ccw, __u32 intparm)
 323 {
 324         int ret;
 325         unsigned long flags;
 326         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 327
 328         mutex_lock(&vcdev->io_lock);
 329         do {
 330                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 331                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 332                 if (!ret) {
 333                         if (!vcdev->curr_io)
 334                                 vcdev->err = 0;
 335                         vcdev->curr_io |= flag;
 336                 }
 337                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 338                 cpu_relax();
 339         } while (ret == -EBUSY);
 340         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 341         ret = ret ? ret : vcdev->err;
 342         mutex_unlock(&vcdev->io_lock);
 343         return ret;
 344 }
 345
 346 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 347                                       struct ccw1 *ccw)
 348 {
 349         int ret;
 350         unsigned long *indicatorp = NULL;
 351         struct virtio_thinint_area *thinint_area = NULL;
 352         struct airq_info *airq_info = vcdev->airq_info;
 353
 354         if (vcdev->is_thinint) {
 355                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 356                                                      sizeof(*thinint_area));
 357                 if (!thinint_area)
 358                         return;
 359                 thinint_area->summary_indicator =
 360                         (unsigned long) get_summary_indicator(airq_info);
 361                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 362                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 363                 ccw->count = sizeof(*thinint_area);
 364                 ccw->cda = (__u32)(unsigned long) thinint_area;
 365         } else {
 366                 /* payload is the address of the indicators */
 367                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 368                                                    sizeof(indicators(vcdev)));
 369                 if (!indicatorp)
 370                         return;
 371                 *indicatorp = 0;
 372                 ccw->cmd_code = CCW_CMD_SET_IND;
 373                 ccw->count = sizeof(indicators(vcdev));
 374                 ccw->cda = (__u32)(unsigned long) indicatorp;
 375         }
 376         /* Deregister indicators from host. */
 377         *indicators(vcdev) = 0;
 378         ccw->flags = 0;
 379         ret = ccw_io_helper(vcdev, ccw,
 380                             vcdev->is_thinint ?
 381                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 382                             VIRTIO_CCW_DOING_SET_IND);
 383         if (ret && (ret != -ENODEV))
 384                 dev_info(&vcdev->cdev->dev,
 385                          "Failed to deregister indicators (%d)\n", ret);
 386         else if (vcdev->is_thinint)
 387                 virtio_ccw_drop_indicators(vcdev);
 388         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
 389         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 390 }
 391
 392 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 393 {
 394         struct virtio_ccw_vq_info *info = vq->priv;
 395         struct virtio_ccw_device *vcdev;
 396         struct subchannel_id schid;
 397
 398         vcdev = to_vc_device(info->vq->vdev);
 399         ccw_device_get_schid(vcdev->cdev, &schid);
 400         BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
 401         info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
 402                                       *((unsigned int *)&schid),
 403                                       vq->index, info->cookie);
 404         if (info->cookie < 0)
 405                 return false;
 406         return true;
 407 }
 408
 409 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 410                                    struct ccw1 *ccw, int index)
 411 {
 412         int ret;
 413
 414         vcdev->dma_area->config_block.index = index;
 415         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 416         ccw->flags = 0;
 417         ccw->count = sizeof(struct vq_config_block);
 418         ccw->cda = (__u32)(unsigned long)(&vcdev->dma_area->config_block);
 419         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 420         if (ret)
 421                 return ret;
 422         return vcdev->dma_area->config_block.num ?: -ENOENT;
 423 }
 424
 425 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 426 {
 427         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 428         struct virtio_ccw_vq_info *info = vq->priv;
 429         unsigned long flags;
 430         int ret;
 431         unsigned int index = vq->index;
 432
 433         /* Remove from our list. */
 434         spin_lock_irqsave(&vcdev->lock, flags);
 435         list_del(&info->node);
 436         spin_unlock_irqrestore(&vcdev->lock, flags);
 437
 438         /* Release from host. */
 439         if (vcdev->revision == 0) {
 440                 info->info_block->l.queue = 0;
 441                 info->info_block->l.align = 0;
 442                 info->info_block->l.index = index;
 443                 info->info_block->l.num = 0;
 444                 ccw->count = sizeof(info->info_block->l);
 445         } else {
 446                 info->info_block->s.desc = 0;
 447                 info->info_block->s.index = index;
 448                 info->info_block->s.num = 0;
 449                 info->info_block->s.avail = 0;
 450                 info->info_block->s.used = 0;
 451                 ccw->count = sizeof(info->info_block->s);
 452         }
 453         ccw->cmd_code = CCW_CMD_SET_VQ;
 454         ccw->flags = 0;
 455         ccw->cda = (__u32)(unsigned long)(info->info_block);
 456         ret = ccw_io_helper(vcdev, ccw,
 457                             VIRTIO_CCW_DOING_SET_VQ | index);
 458         /*
 459          * -ENODEV isn't considered an error: The device is gone anyway.
 460          * This may happen on device detach.
 461          */
 462         if (ret && (ret != -ENODEV))
 463                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 464                          ret, index);
 465
 466         vring_del_virtqueue(vq);
 467         ccw_device_dma_free(vcdev->cdev, info->info_block,
 468                             sizeof(*info->info_block));
 469         kfree(info);
 470 }
 471
 472 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 473 {
 474         struct virtqueue *vq, *n;
 475         struct ccw1 *ccw;
 476         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 477
 478         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 479         if (!ccw)
 480                 return;
 481
 482         virtio_ccw_drop_indicator(vcdev, ccw);
 483
 484         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 485                 virtio_ccw_del_vq(vq, ccw);
 486
 487         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 488 }
 489
 490 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 491                                              int i, vq_callback_t *callback,
 492                                              const char *name, bool ctx,
 493                                              struct ccw1 *ccw)
 494 {
 495         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 496         int err;
 497         struct virtqueue *vq = NULL;
 498         struct virtio_ccw_vq_info *info;
 499         u64 queue;
 500         unsigned long flags;
 501         bool may_reduce;
 502
 503         /* Allocate queue. */
 504         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 505         if (!info) {
 506                 dev_warn(&vcdev->cdev->dev, "no info\n");
 507                 err = -ENOMEM;
 508                 goto out_err;
 509         }
 510         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 511                                                  sizeof(*info->info_block));
 512         if (!info->info_block) {
 513                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 514                 err = -ENOMEM;
 515                 goto out_err;
 516         }
 517         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 518         if (info->num < 0) {
 519                 err = info->num;
 520                 goto out_err;
 521         }
 522         may_reduce = vcdev->revision > 0;
 523         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 524                                     vdev, true, may_reduce, ctx,
 525                                     virtio_ccw_kvm_notify, callback, name);
 526
 527         if (!vq) {
 528                 /* For now, we fail if we can't get the requested size. */
 529                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 530                 err = -ENOMEM;
 531                 goto out_err;
 532         }
 533         /* it may have been reduced */
 534         info->num = virtqueue_get_vring_size(vq);
 535
 536         /* Register it with the host. */
 537         queue = virtqueue_get_desc_addr(vq);
 538         if (vcdev->revision == 0) {
 539                 info->info_block->l.queue = 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 = 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_addr(vq);
 549                 info->info_block->s.used = (__u64)virtqueue_get_used_addr(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                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 576                                     sizeof(*info->info_block));
 577         }
 578         kfree(info);
 579         return ERR_PTR(err);
 580 }
 581
 582 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 583                                            struct virtqueue *vqs[], int nvqs,
 584                                            struct ccw1 *ccw)
 585 {
 586         int ret;
 587         struct virtio_thinint_area *thinint_area = NULL;
 588         struct airq_info *info;
 589
 590         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 591                                              sizeof(*thinint_area));
 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) get_summary_indicator(info);
 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         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*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 = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 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 = ccw_device_dma_zalloc(vcdev->cdev,
 668                                            sizeof(indicators(vcdev)));
 669         if (!indicatorp)
 670                 goto out;
 671         *indicatorp = (unsigned long) indicators(vcdev);
 672         if (vcdev->is_thinint) {
 673                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 674                 if (ret)
 675                         /* no error, just fall back to legacy interrupts */
 676                         vcdev->is_thinint = false;
 677         }
 678         if (!vcdev->is_thinint) {
 679                 /* Register queue indicators with host. */
 680                 *indicators(vcdev) = 0;
 681                 ccw->cmd_code = CCW_CMD_SET_IND;
 682                 ccw->flags = 0;
 683                 ccw->count = sizeof(indicators(vcdev));
 684                 ccw->cda = (__u32)(unsigned long) indicatorp;
 685                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 686                 if (ret)
 687                         goto out;
 688         }
 689         /* Register indicators2 with host for config changes */
 690         *indicatorp = (unsigned long) indicators2(vcdev);
 691         *indicators2(vcdev) = 0;
 692         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 693         ccw->flags = 0;
 694         ccw->count = sizeof(indicators2(vcdev));
 695         ccw->cda = (__u32)(unsigned long) indicatorp;
 696         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 697         if (ret)
 698                 goto out;
 699
 700         if (indicatorp)
 701                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 702                                     sizeof(indicators(vcdev)));
 703         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 704         return 0;
 705 out:
 706         if (indicatorp)
 707                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 708                                     sizeof(indicators(vcdev)));
 709         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 710         virtio_ccw_del_vqs(vdev);
 711         return ret;
 712 }
 713
 714 static void virtio_ccw_reset(struct virtio_device *vdev)
 715 {
 716         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 717         struct ccw1 *ccw;
 718
 719         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 720         if (!ccw)
 721                 return;
 722
 723         /* Zero status bits. */
 724         vcdev->dma_area->status = 0;
 725
 726         /* Send a reset ccw on device. */
 727         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 728         ccw->flags = 0;
 729         ccw->count = 0;
 730         ccw->cda = 0;
 731         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 732         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 733 }
 734
 735 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 736 {
 737         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 738         struct virtio_feature_desc *features;
 739         int ret;
 740         u64 rc;
 741         struct ccw1 *ccw;
 742
 743         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 744         if (!ccw)
 745                 return 0;
 746
 747         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 748         if (!features) {
 749                 rc = 0;
 750                 goto out_free;
 751         }
 752         /* Read the feature bits from the host. */
 753         features->index = 0;
 754         ccw->cmd_code = CCW_CMD_READ_FEAT;
 755         ccw->flags = 0;
 756         ccw->count = sizeof(*features);
 757         ccw->cda = (__u32)(unsigned long)features;
 758         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 759         if (ret) {
 760                 rc = 0;
 761                 goto out_free;
 762         }
 763
 764         rc = le32_to_cpu(features->features);
 765
 766         if (vcdev->revision == 0)
 767                 goto out_free;
 768
 769         /* Read second half of the feature bits from the host. */
 770         features->index = 1;
 771         ccw->cmd_code = CCW_CMD_READ_FEAT;
 772         ccw->flags = 0;
 773         ccw->count = sizeof(*features);
 774         ccw->cda = (__u32)(unsigned long)features;
 775         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 776         if (ret == 0)
 777                 rc |= (u64)le32_to_cpu(features->features) << 32;
 778
 779 out_free:
 780         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 781         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 782         return rc;
 783 }
 784
 785 static void ccw_transport_features(struct virtio_device *vdev)
 786 {
 787         /*
 788          * Currently nothing to do here.
 789          */
 790 }
 791
 792 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 793 {
 794         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 795         struct virtio_feature_desc *features;
 796         struct ccw1 *ccw;
 797         int ret;
 798
 799         if (vcdev->revision >= 1 &&
 800             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 801                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 802                         "but does not have VIRTIO_F_VERSION_1\n");
 803                 return -EINVAL;
 804         }
 805
 806         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 807         if (!ccw)
 808                 return -ENOMEM;
 809
 810         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 811         if (!features) {
 812                 ret = -ENOMEM;
 813                 goto out_free;
 814         }
 815         /* Give virtio_ring a chance to accept features. */
 816         vring_transport_features(vdev);
 817
 818         /* Give virtio_ccw a chance to accept features. */
 819         ccw_transport_features(vdev);
 820
 821         features->index = 0;
 822         features->features = cpu_to_le32((u32)vdev->features);
 823         /* Write the first half of the feature bits to the host. */
 824         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 825         ccw->flags = 0;
 826         ccw->count = sizeof(*features);
 827         ccw->cda = (__u32)(unsigned long)features;
 828         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 829         if (ret)
 830                 goto out_free;
 831
 832         if (vcdev->revision == 0)
 833                 goto out_free;
 834
 835         features->index = 1;
 836         features->features = cpu_to_le32(vdev->features >> 32);
 837         /* Write the second half of the feature bits to the host. */
 838         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 839         ccw->flags = 0;
 840         ccw->count = sizeof(*features);
 841         ccw->cda = (__u32)(unsigned long)features;
 842         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 843
 844 out_free:
 845         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 846         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 847
 848         return ret;
 849 }
 850
 851 static void virtio_ccw_get_config(struct virtio_device *vdev,
 852                                   unsigned int offset, void *buf, unsigned len)
 853 {
 854         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 855         int ret;
 856         struct ccw1 *ccw;
 857         void *config_area;
 858         unsigned long flags;
 859
 860         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 861         if (!ccw)
 862                 return;
 863
 864         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 865                                             VIRTIO_CCW_CONFIG_SIZE);
 866         if (!config_area)
 867                 goto out_free;
 868
 869         /* Read the config area from the host. */
 870         ccw->cmd_code = CCW_CMD_READ_CONF;
 871         ccw->flags = 0;
 872         ccw->count = offset + len;
 873         ccw->cda = (__u32)(unsigned long)config_area;
 874         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 875         if (ret)
 876                 goto out_free;
 877
 878         spin_lock_irqsave(&vcdev->lock, flags);
 879         memcpy(vcdev->config, config_area, offset + len);
 880         if (vcdev->config_ready < offset + len)
 881                 vcdev->config_ready = offset + len;
 882         spin_unlock_irqrestore(&vcdev->lock, flags);
 883         if (buf)
 884                 memcpy(buf, config_area + offset, len);
 885
 886 out_free:
 887         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 888         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 889 }
 890
 891 static void virtio_ccw_set_config(struct virtio_device *vdev,
 892                                   unsigned int offset, const void *buf,
 893                                   unsigned len)
 894 {
 895         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 896         struct ccw1 *ccw;
 897         void *config_area;
 898         unsigned long flags;
 899
 900         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 901         if (!ccw)
 902                 return;
 903
 904         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 905                                             VIRTIO_CCW_CONFIG_SIZE);
 906         if (!config_area)
 907                 goto out_free;
 908
 909         /* Make sure we don't overwrite fields. */
 910         if (vcdev->config_ready < offset)
 911                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 912         spin_lock_irqsave(&vcdev->lock, flags);
 913         memcpy(&vcdev->config[offset], buf, len);
 914         /* Write the config area to the host. */
 915         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 916         spin_unlock_irqrestore(&vcdev->lock, flags);
 917         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 918         ccw->flags = 0;
 919         ccw->count = offset + len;
 920         ccw->cda = (__u32)(unsigned long)config_area;
 921         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 922
 923 out_free:
 924         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 925         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 926 }
 927
 928 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 929 {
 930         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 931         u8 old_status = vcdev->dma_area->status;
 932         struct ccw1 *ccw;
 933
 934         if (vcdev->revision < 2)
 935                 return vcdev->dma_area->status;
 936
 937         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 938         if (!ccw)
 939                 return old_status;
 940
 941         ccw->cmd_code = CCW_CMD_READ_STATUS;
 942         ccw->flags = 0;
 943         ccw->count = sizeof(vcdev->dma_area->status);
 944         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 945         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 946 /*
 947  * If the channel program failed (should only happen if the device
 948  * was hotunplugged, and then we clean up via the machine check
 949  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 950  * return the old status, which is fine.
 951 */
 952         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 953
 954         return vcdev->dma_area->status;
 955 }
 956
 957 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 958 {
 959         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 960         u8 old_status = vcdev->dma_area->status;
 961         struct ccw1 *ccw;
 962         int ret;
 963
 964         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 965         if (!ccw)
 966                 return;
 967
 968         /* Write the status to the host. */
 969         vcdev->dma_area->status = status;
 970         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 971         ccw->flags = 0;
 972         ccw->count = sizeof(status);
 973         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 974         /* We use ssch for setting the status which is a serializing
 975          * instruction that guarantees the memory writes have
 976          * completed before ssch.
 977          */
 978         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 979         /* Write failed? We assume status is unchanged. */
 980         if (ret)
 981                 vcdev->dma_area->status = old_status;
 982         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 983 }
 984
 985 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 986 {
 987         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 988
 989         return dev_name(&vcdev->cdev->dev);
 990 }
 991
 992 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
 993 {
 994         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 995         struct airq_info *info = vcdev->airq_info;
 996
 997         if (info) {
 998                 /*
 999                  * This device uses adapter interrupts: synchronize with
1000                  * vring_interrupt() called by virtio_airq_handler()
1001                  * via the indicator area lock.
1002                  */
1003                 write_lock_irq(&info->lock);
1004                 write_unlock_irq(&info->lock);
1005         } else {
1006                 /* This device uses classic interrupts: synchronize
1007                  * with vring_interrupt() called by
1008                  * virtio_ccw_int_handler() via the per-device
1009                  * irq_lock
1010                  */
1011                 write_lock_irq(&vcdev->irq_lock);
1012                 write_unlock_irq(&vcdev->irq_lock);
1013         }
1014 }
1015
1016 static const struct virtio_config_ops virtio_ccw_config_ops = {
1017         .get_features = virtio_ccw_get_features,
1018         .finalize_features = virtio_ccw_finalize_features,
1019         .get = virtio_ccw_get_config,
1020         .set = virtio_ccw_set_config,
1021         .get_status = virtio_ccw_get_status,
1022         .set_status = virtio_ccw_set_status,
1023         .reset = virtio_ccw_reset,
1024         .find_vqs = virtio_ccw_find_vqs,
1025         .del_vqs = virtio_ccw_del_vqs,
1026         .bus_name = virtio_ccw_bus_name,
1027         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1028 };
1029
1030
1031 /*
1032  * ccw bus driver related functions
1033  */
1034
1035 static void virtio_ccw_release_dev(struct device *_d)
1036 {
1037         struct virtio_device *dev = dev_to_virtio(_d);
1038         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1039
1040         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1041                             sizeof(*vcdev->dma_area));
1042         kfree(vcdev);
1043 }
1044
1045 static int irb_is_error(struct irb *irb)
1046 {
1047         if (scsw_cstat(&irb->scsw) != 0)
1048                 return 1;
1049         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1050                 return 1;
1051         if (scsw_cc(&irb->scsw) != 0)
1052                 return 1;
1053         return 0;
1054 }
1055
1056 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1057                                               int index)
1058 {
1059         struct virtio_ccw_vq_info *info;
1060         unsigned long flags;
1061         struct virtqueue *vq;
1062
1063         vq = NULL;
1064         spin_lock_irqsave(&vcdev->lock, flags);
1065         list_for_each_entry(info, &vcdev->virtqueues, node) {
1066                 if (info->vq->index == index) {
1067                         vq = info->vq;
1068                         break;
1069                 }
1070         }
1071         spin_unlock_irqrestore(&vcdev->lock, flags);
1072         return vq;
1073 }
1074
1075 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1076                                       __u32 activity)
1077 {
1078         if (vcdev->curr_io & activity) {
1079                 switch (activity) {
1080                 case VIRTIO_CCW_DOING_READ_FEAT:
1081                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1082                 case VIRTIO_CCW_DOING_READ_CONFIG:
1083                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1084                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1085                 case VIRTIO_CCW_DOING_READ_STATUS:
1086                 case VIRTIO_CCW_DOING_SET_VQ:
1087                 case VIRTIO_CCW_DOING_SET_IND:
1088                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1089                 case VIRTIO_CCW_DOING_RESET:
1090                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1091                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1092                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1093                         vcdev->curr_io &= ~activity;
1094                         wake_up(&vcdev->wait_q);
1095                         break;
1096                 default:
1097                         /* don't know what to do... */
1098                         dev_warn(&vcdev->cdev->dev,
1099                                  "Suspicious activity '%08x'\n", activity);
1100                         WARN_ON(1);
1101                         break;
1102                 }
1103         }
1104 }
1105
1106 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1107                                    unsigned long intparm,
1108                                    struct irb *irb)
1109 {
1110         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1111         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1112         int i;
1113         struct virtqueue *vq;
1114
1115         if (!vcdev)
1116                 return;
1117         if (IS_ERR(irb)) {
1118                 vcdev->err = PTR_ERR(irb);
1119                 virtio_ccw_check_activity(vcdev, activity);
1120                 /* Don't poke around indicators, something's wrong. */
1121                 return;
1122         }
1123         /* Check if it's a notification from the host. */
1124         if ((intparm == 0) &&
1125             (scsw_stctl(&irb->scsw) ==
1126              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1127                 /* OK */
1128         }
1129         if (irb_is_error(irb)) {
1130                 /* Command reject? */
1131                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1132                     (irb->ecw[0] & SNS0_CMD_REJECT))
1133                         vcdev->err = -EOPNOTSUPP;
1134                 else
1135                         /* Map everything else to -EIO. */
1136                         vcdev->err = -EIO;
1137         }
1138         virtio_ccw_check_activity(vcdev, activity);
1139 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1140         /*
1141          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1142          * disabled here.
1143          */
1144         read_lock(&vcdev->irq_lock);
1145 #endif
1146         for_each_set_bit(i, indicators(vcdev),
1147                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1148                 /* The bit clear must happen before the vring kick. */
1149                 clear_bit(i, indicators(vcdev));
1150                 barrier();
1151                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1152                 vring_interrupt(0, vq);
1153         }
1154 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1155         read_unlock(&vcdev->irq_lock);
1156 #endif
1157         if (test_bit(0, indicators2(vcdev))) {
1158                 virtio_config_changed(&vcdev->vdev);
1159                 clear_bit(0, indicators2(vcdev));
1160         }
1161 }
1162
1163 /*
1164  * We usually want to autoonline all devices, but give the admin
1165  * a way to exempt devices from this.
1166  */
1167 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1168                      (8*sizeof(long)))
1169 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1170
1171 static char *no_auto = "";
1172
1173 module_param(no_auto, charp, 0444);
1174 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1175
1176 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1177 {
1178         struct ccw_dev_id id;
1179
1180         ccw_device_get_id(cdev, &id);
1181         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1182                 return 0;
1183         return 1;
1184 }
1185
1186 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1187 {
1188         struct ccw_device *cdev = data;
1189         int ret;
1190
1191         ret = ccw_device_set_online(cdev);
1192         if (ret)
1193                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1194 }
1195
1196 static int virtio_ccw_probe(struct ccw_device *cdev)
1197 {
1198         cdev->handler = virtio_ccw_int_handler;
1199
1200         if (virtio_ccw_check_autoonline(cdev))
1201                 async_schedule(virtio_ccw_auto_online, cdev);
1202         return 0;
1203 }
1204
1205 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1206 {
1207         unsigned long flags;
1208         struct virtio_ccw_device *vcdev;
1209
1210         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1211         vcdev = dev_get_drvdata(&cdev->dev);
1212         if (!vcdev || vcdev->going_away) {
1213                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1214                 return NULL;
1215         }
1216         vcdev->going_away = true;
1217         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1218         return vcdev;
1219 }
1220
1221 static void virtio_ccw_remove(struct ccw_device *cdev)
1222 {
1223         unsigned long flags;
1224         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1225
1226         if (vcdev && cdev->online) {
1227                 if (vcdev->device_lost)
1228                         virtio_break_device(&vcdev->vdev);
1229                 unregister_virtio_device(&vcdev->vdev);
1230                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1231                 dev_set_drvdata(&cdev->dev, NULL);
1232                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1233         }
1234         cdev->handler = NULL;
1235 }
1236
1237 static int virtio_ccw_offline(struct ccw_device *cdev)
1238 {
1239         unsigned long flags;
1240         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1241
1242         if (!vcdev)
1243                 return 0;
1244         if (vcdev->device_lost)
1245                 virtio_break_device(&vcdev->vdev);
1246         unregister_virtio_device(&vcdev->vdev);
1247         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1248         dev_set_drvdata(&cdev->dev, NULL);
1249         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1250         return 0;
1251 }
1252
1253 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1254 {
1255         struct virtio_rev_info *rev;
1256         struct ccw1 *ccw;
1257         int ret;
1258
1259         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1260         if (!ccw)
1261                 return -ENOMEM;
1262         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1263         if (!rev) {
1264                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1265                 return -ENOMEM;
1266         }
1267
1268         /* Set transport revision */
1269         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1270         ccw->flags = 0;
1271         ccw->count = sizeof(*rev);
1272         ccw->cda = (__u32)(unsigned long)rev;
1273
1274         vcdev->revision = VIRTIO_CCW_REV_MAX;
1275         do {
1276                 rev->revision = vcdev->revision;
1277                 /* none of our supported revisions carry payload */
1278                 rev->length = 0;
1279                 ret = ccw_io_helper(vcdev, ccw,
1280                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1281                 if (ret == -EOPNOTSUPP) {
1282                         if (vcdev->revision == 0)
1283                                 /*
1284                                  * The host device does not support setting
1285                                  * the revision: let's operate it in legacy
1286                                  * mode.
1287                                  */
1288                                 ret = 0;
1289                         else
1290                                 vcdev->revision--;
1291                 }
1292         } while (ret == -EOPNOTSUPP);
1293
1294         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1295         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1296         return ret;
1297 }
1298
1299 static int virtio_ccw_online(struct ccw_device *cdev)
1300 {
1301         int ret;
1302         struct virtio_ccw_device *vcdev;
1303         unsigned long flags;
1304
1305         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1306         if (!vcdev) {
1307                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1308                 ret = -ENOMEM;
1309                 goto out_free;
1310         }
1311         vcdev->vdev.dev.parent = &cdev->dev;
1312         vcdev->cdev = cdev;
1313         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1314                                                 sizeof(*vcdev->dma_area));
1315         if (!vcdev->dma_area) {
1316                 ret = -ENOMEM;
1317                 goto out_free;
1318         }
1319
1320         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1321
1322         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1323         vcdev->vdev.config = &virtio_ccw_config_ops;
1324         init_waitqueue_head(&vcdev->wait_q);
1325         INIT_LIST_HEAD(&vcdev->virtqueues);
1326         spin_lock_init(&vcdev->lock);
1327         rwlock_init(&vcdev->irq_lock);
1328         mutex_init(&vcdev->io_lock);
1329
1330         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1331         dev_set_drvdata(&cdev->dev, vcdev);
1332         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1333         vcdev->vdev.id.vendor = cdev->id.cu_type;
1334         vcdev->vdev.id.device = cdev->id.cu_model;
1335
1336         ret = virtio_ccw_set_transport_rev(vcdev);
1337         if (ret)
1338                 goto out_free;
1339
1340         ret = register_virtio_device(&vcdev->vdev);
1341         if (ret) {
1342                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1343                          ret);
1344                 goto out_put;
1345         }
1346         return 0;
1347 out_put:
1348         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1349         dev_set_drvdata(&cdev->dev, NULL);
1350         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1351         put_device(&vcdev->vdev.dev);
1352         return ret;
1353 out_free:
1354         if (vcdev) {
1355                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1356                                     sizeof(*vcdev->dma_area));
1357         }
1358         kfree(vcdev);
1359         return ret;
1360 }
1361
1362 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1363 {
1364         int rc;
1365         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1366
1367         /*
1368          * Make sure vcdev is set
1369          * i.e. set_offline/remove callback not already running
1370          */
1371         if (!vcdev)
1372                 return NOTIFY_DONE;
1373
1374         switch (event) {
1375         case CIO_GONE:
1376                 vcdev->device_lost = true;
1377                 rc = NOTIFY_DONE;
1378                 break;
1379         case CIO_OPER:
1380                 rc = NOTIFY_OK;
1381                 break;
1382         default:
1383                 rc = NOTIFY_DONE;
1384                 break;
1385         }
1386         return rc;
1387 }
1388
1389 static struct ccw_device_id virtio_ids[] = {
1390         { CCW_DEVICE(0x3832, 0) },
1391         {},
1392 };
1393
1394 static struct ccw_driver virtio_ccw_driver = {
1395         .driver = {
1396                 .owner = THIS_MODULE,
1397                 .name = "virtio_ccw",
1398         },
1399         .ids = virtio_ids,
1400         .probe = virtio_ccw_probe,
1401         .remove = virtio_ccw_remove,
1402         .set_offline = virtio_ccw_offline,
1403         .set_online = virtio_ccw_online,
1404         .notify = virtio_ccw_cio_notify,
1405         .int_class = IRQIO_VIR,
1406 };
1407
1408 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1409                            int max_digit, int max_val)
1410 {
1411         int diff;
1412
1413         diff = 0;
1414         *val = 0;
1415
1416         while (diff <= max_digit) {
1417                 int value = hex_to_bin(**cp);
1418
1419                 if (value < 0)
1420                         break;
1421                 *val = *val * 16 + value;
1422                 (*cp)++;
1423                 diff++;
1424         }
1425
1426         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1427                 return 1;
1428
1429         return 0;
1430 }
1431
1432 static int __init parse_busid(char *str, unsigned int *cssid,
1433                               unsigned int *ssid, unsigned int *devno)
1434 {
1435         char *str_work;
1436         int rc, ret;
1437
1438         rc = 1;
1439
1440         if (*str == '\0')
1441                 goto out;
1442
1443         str_work = str;
1444         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1445         if (ret || (str_work[0] != '.'))
1446                 goto out;
1447         str_work++;
1448         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1449         if (ret || (str_work[0] != '.'))
1450                 goto out;
1451         str_work++;
1452         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1453         if (ret || (str_work[0] != '\0'))
1454                 goto out;
1455
1456         rc = 0;
1457 out:
1458         return rc;
1459 }
1460
1461 static void __init no_auto_parse(void)
1462 {
1463         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1464         char *parm, *str;
1465         int rc;
1466
1467         str = no_auto;
1468         while ((parm = strsep(&str, ","))) {
1469                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1470                                  &from_ssid, &from);
1471                 if (rc)
1472                         continue;
1473                 if (parm != NULL) {
1474                         rc = parse_busid(parm, &to_cssid,
1475                                          &to_ssid, &to);
1476                         if ((from_ssid > to_ssid) ||
1477                             ((from_ssid == to_ssid) && (from > to)))
1478                                 rc = -EINVAL;
1479                 } else {
1480                         to_cssid = from_cssid;
1481                         to_ssid = from_ssid;
1482                         to = from;
1483                 }
1484                 if (rc)
1485                         continue;
1486                 while ((from_ssid < to_ssid) ||
1487                        ((from_ssid == to_ssid) && (from <= to))) {
1488                         set_bit(from, devs_no_auto[from_ssid]);
1489                         from++;
1490                         if (from > __MAX_SUBCHANNEL) {
1491                                 from_ssid++;
1492                                 from = 0;
1493                         }
1494                 }
1495         }
1496 }
1497
1498 static int __init virtio_ccw_init(void)
1499 {
1500         int rc;
1501
1502         /* parse no_auto string before we do anything further */
1503         no_auto_parse();
1504
1505         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1506         if (!summary_indicators)
1507                 return -ENOMEM;
1508         rc = ccw_driver_register(&virtio_ccw_driver);
1509         if (rc)
1510                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1511         return rc;
1512 }
1513 device_initcall(virtio_ccw_init);