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         struct mutex io_lock; /* Serializes I/O requests */
  66         struct list_head virtqueues;
  67         bool is_thinint;
  68         bool going_away;
  69         bool device_lost;
  70         unsigned int config_ready;
  71         void *airq_info;
  72         struct vcdev_dma_area *dma_area;
  73 };
  74
  75 static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  76 {
  77         return &vcdev->dma_area->indicators;
  78 }
  79
  80 static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  81 {
  82         return &vcdev->dma_area->indicators2;
  83 }
  84
  85 struct vq_info_block_legacy {
  86         __u64 queue;
  87         __u32 align;
  88         __u16 index;
  89         __u16 num;
  90 } __packed;
  91
  92 struct vq_info_block {
  93         __u64 desc;
  94         __u32 res0;
  95         __u16 index;
  96         __u16 num;
  97         __u64 avail;
  98         __u64 used;
  99 } __packed;
 100
 101 struct virtio_feature_desc {
 102         __le32 features;
 103         __u8 index;
 104 } __packed;
 105
 106 struct virtio_thinint_area {
 107         unsigned long summary_indicator;
 108         unsigned long indicator;
 109         u64 bit_nr;
 110         u8 isc;
 111 } __packed;
 112
 113 struct virtio_rev_info {
 114         __u16 revision;
 115         __u16 length;
 116         __u8 data[];
 117 };
 118
 119 /* the highest virtio-ccw revision we support */
 120 #define VIRTIO_CCW_REV_MAX 1
 121
 122 struct virtio_ccw_vq_info {
 123         struct virtqueue *vq;
 124         int num;
 125         union {
 126                 struct vq_info_block s;
 127                 struct vq_info_block_legacy l;
 128         } *info_block;
 129         int bit_nr;
 130         struct list_head node;
 131         long cookie;
 132 };
 133
 134 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 135
 136 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 137 #define MAX_AIRQ_AREAS 20
 138
 139 static int virtio_ccw_use_airq = 1;
 140
 141 struct airq_info {
 142         rwlock_t lock;
 143         u8 summary_indicator_idx;
 144         struct airq_struct airq;
 145         struct airq_iv *aiv;
 146 };
 147 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 148 static u8 *summary_indicators;
 149
 150 static inline u8 *get_summary_indicator(struct airq_info *info)
 151 {
 152         return summary_indicators + info->summary_indicator_idx;
 153 }
 154
 155 #define CCW_CMD_SET_VQ 0x13
 156 #define CCW_CMD_VDEV_RESET 0x33
 157 #define CCW_CMD_SET_IND 0x43
 158 #define CCW_CMD_SET_CONF_IND 0x53
 159 #define CCW_CMD_READ_FEAT 0x12
 160 #define CCW_CMD_WRITE_FEAT 0x11
 161 #define CCW_CMD_READ_CONF 0x22
 162 #define CCW_CMD_WRITE_CONF 0x21
 163 #define CCW_CMD_WRITE_STATUS 0x31
 164 #define CCW_CMD_READ_VQ_CONF 0x32
 165 #define CCW_CMD_READ_STATUS 0x72
 166 #define CCW_CMD_SET_IND_ADAPTER 0x73
 167 #define CCW_CMD_SET_VIRTIO_REV 0x83
 168
 169 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 170 #define VIRTIO_CCW_DOING_RESET 0x00040000
 171 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 172 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 173 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 174 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 175 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 176 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 177 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 178 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 179 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 180 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 181 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 182 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 183
 184 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 185 {
 186         return container_of(vdev, struct virtio_ccw_device, vdev);
 187 }
 188
 189 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 190 {
 191         unsigned long i, flags;
 192
 193         write_lock_irqsave(&info->lock, flags);
 194         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 195                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 196                         airq_iv_free_bit(info->aiv, i);
 197                         airq_iv_set_ptr(info->aiv, i, 0);
 198                         break;
 199                 }
 200         }
 201         write_unlock_irqrestore(&info->lock, flags);
 202 }
 203
 204 static void virtio_airq_handler(struct airq_struct *airq, bool floating)
 205 {
 206         struct airq_info *info = container_of(airq, struct airq_info, airq);
 207         unsigned long ai;
 208
 209         inc_irq_stat(IRQIO_VAI);
 210         read_lock(&info->lock);
 211         /* Walk through indicators field, summary indicator active. */
 212         for (ai = 0;;) {
 213                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 214                 if (ai == -1UL)
 215                         break;
 216                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 217         }
 218         *(get_summary_indicator(info)) = 0;
 219         smp_wmb();
 220         /* Walk through indicators field, summary indicator not active. */
 221         for (ai = 0;;) {
 222                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 223                 if (ai == -1UL)
 224                         break;
 225                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 226         }
 227         read_unlock(&info->lock);
 228 }
 229
 230 static struct airq_info *new_airq_info(int index)
 231 {
 232         struct airq_info *info;
 233         int rc;
 234
 235         info = kzalloc(sizeof(*info), GFP_KERNEL);
 236         if (!info)
 237                 return NULL;
 238         rwlock_init(&info->lock);
 239         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 240                                    | AIRQ_IV_CACHELINE);
 241         if (!info->aiv) {
 242                 kfree(info);
 243                 return NULL;
 244         }
 245         info->airq.handler = virtio_airq_handler;
 246         info->summary_indicator_idx = index;
 247         info->airq.lsi_ptr = get_summary_indicator(info);
 248         info->airq.lsi_mask = 0xff;
 249         info->airq.isc = VIRTIO_AIRQ_ISC;
 250         rc = register_adapter_interrupt(&info->airq);
 251         if (rc) {
 252                 airq_iv_release(info->aiv);
 253                 kfree(info);
 254                 return NULL;
 255         }
 256         return info;
 257 }
 258
 259 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 260                                         u64 *first, void **airq_info)
 261 {
 262         int i, j;
 263         struct airq_info *info;
 264         unsigned long indicator_addr = 0;
 265         unsigned long bit, flags;
 266
 267         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 268                 if (!airq_areas[i])
 269                         airq_areas[i] = new_airq_info(i);
 270                 info = airq_areas[i];
 271                 if (!info)
 272                         return 0;
 273                 write_lock_irqsave(&info->lock, flags);
 274                 bit = airq_iv_alloc(info->aiv, nvqs);
 275                 if (bit == -1UL) {
 276                         /* Not enough vacancies. */
 277                         write_unlock_irqrestore(&info->lock, flags);
 278                         continue;
 279                 }
 280                 *first = bit;
 281                 *airq_info = info;
 282                 indicator_addr = (unsigned long)info->aiv->vector;
 283                 for (j = 0; j < nvqs; j++) {
 284                         airq_iv_set_ptr(info->aiv, bit + j,
 285                                         (unsigned long)vqs[j]);
 286                 }
 287                 write_unlock_irqrestore(&info->lock, flags);
 288         }
 289         return indicator_addr;
 290 }
 291
 292 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 293 {
 294         struct virtio_ccw_vq_info *info;
 295
 296         if (!vcdev->airq_info)
 297                 return;
 298         list_for_each_entry(info, &vcdev->virtqueues, node)
 299                 drop_airq_indicator(info->vq, vcdev->airq_info);
 300 }
 301
 302 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 303 {
 304         unsigned long flags;
 305         __u32 ret;
 306
 307         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 308         if (vcdev->err)
 309                 ret = 0;
 310         else
 311                 ret = vcdev->curr_io & flag;
 312         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 313         return ret;
 314 }
 315
 316 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 317                          struct ccw1 *ccw, __u32 intparm)
 318 {
 319         int ret;
 320         unsigned long flags;
 321         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 322
 323         mutex_lock(&vcdev->io_lock);
 324         do {
 325                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 326                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 327                 if (!ret) {
 328                         if (!vcdev->curr_io)
 329                                 vcdev->err = 0;
 330                         vcdev->curr_io |= flag;
 331                 }
 332                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 333                 cpu_relax();
 334         } while (ret == -EBUSY);
 335         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 336         ret = ret ? ret : vcdev->err;
 337         mutex_unlock(&vcdev->io_lock);
 338         return ret;
 339 }
 340
 341 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 342                                       struct ccw1 *ccw)
 343 {
 344         int ret;
 345         unsigned long *indicatorp = NULL;
 346         struct virtio_thinint_area *thinint_area = NULL;
 347         struct airq_info *airq_info = vcdev->airq_info;
 348
 349         if (vcdev->is_thinint) {
 350                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 351                                                      sizeof(*thinint_area));
 352                 if (!thinint_area)
 353                         return;
 354                 thinint_area->summary_indicator =
 355                         (unsigned long) get_summary_indicator(airq_info);
 356                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 357                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 358                 ccw->count = sizeof(*thinint_area);
 359                 ccw->cda = (__u32)(unsigned long) thinint_area;
 360         } else {
 361                 /* payload is the address of the indicators */
 362                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 363                                                    sizeof(indicators(vcdev)));
 364                 if (!indicatorp)
 365                         return;
 366                 *indicatorp = 0;
 367                 ccw->cmd_code = CCW_CMD_SET_IND;
 368                 ccw->count = sizeof(indicators(vcdev));
 369                 ccw->cda = (__u32)(unsigned long) indicatorp;
 370         }
 371         /* Deregister indicators from host. */
 372         *indicators(vcdev) = 0;
 373         ccw->flags = 0;
 374         ret = ccw_io_helper(vcdev, ccw,
 375                             vcdev->is_thinint ?
 376                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 377                             VIRTIO_CCW_DOING_SET_IND);
 378         if (ret && (ret != -ENODEV))
 379                 dev_info(&vcdev->cdev->dev,
 380                          "Failed to deregister indicators (%d)\n", ret);
 381         else if (vcdev->is_thinint)
 382                 virtio_ccw_drop_indicators(vcdev);
 383         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
 384         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 385 }
 386
 387 static inline long __do_kvm_notify(struct subchannel_id schid,
 388                                    unsigned long queue_index,
 389                                    long cookie)
 390 {
 391         register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 392         register struct subchannel_id __schid asm("2") = schid;
 393         register unsigned long __index asm("3") = queue_index;
 394         register long __rc asm("2");
 395         register long __cookie asm("4") = cookie;
 396
 397         asm volatile ("diag 2,4,0x500\n"
 398                       : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 399                       "d"(__cookie)
 400                       : "memory", "cc");
 401         return __rc;
 402 }
 403
 404 static inline long do_kvm_notify(struct subchannel_id schid,
 405                                  unsigned long queue_index,
 406                                  long cookie)
 407 {
 408         diag_stat_inc(DIAG_STAT_X500);
 409         return __do_kvm_notify(schid, queue_index, cookie);
 410 }
 411
 412 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 413 {
 414         struct virtio_ccw_vq_info *info = vq->priv;
 415         struct virtio_ccw_device *vcdev;
 416         struct subchannel_id schid;
 417
 418         vcdev = to_vc_device(info->vq->vdev);
 419         ccw_device_get_schid(vcdev->cdev, &schid);
 420         info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 421         if (info->cookie < 0)
 422                 return false;
 423         return true;
 424 }
 425
 426 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 427                                    struct ccw1 *ccw, int index)
 428 {
 429         int ret;
 430
 431         vcdev->dma_area->config_block.index = index;
 432         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 433         ccw->flags = 0;
 434         ccw->count = sizeof(struct vq_config_block);
 435         ccw->cda = (__u32)(unsigned long)(&vcdev->dma_area->config_block);
 436         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 437         if (ret)
 438                 return ret;
 439         return vcdev->dma_area->config_block.num ?: -ENOENT;
 440 }
 441
 442 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 443 {
 444         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 445         struct virtio_ccw_vq_info *info = vq->priv;
 446         unsigned long flags;
 447         int ret;
 448         unsigned int index = vq->index;
 449
 450         /* Remove from our list. */
 451         spin_lock_irqsave(&vcdev->lock, flags);
 452         list_del(&info->node);
 453         spin_unlock_irqrestore(&vcdev->lock, flags);
 454
 455         /* Release from host. */
 456         if (vcdev->revision == 0) {
 457                 info->info_block->l.queue = 0;
 458                 info->info_block->l.align = 0;
 459                 info->info_block->l.index = index;
 460                 info->info_block->l.num = 0;
 461                 ccw->count = sizeof(info->info_block->l);
 462         } else {
 463                 info->info_block->s.desc = 0;
 464                 info->info_block->s.index = index;
 465                 info->info_block->s.num = 0;
 466                 info->info_block->s.avail = 0;
 467                 info->info_block->s.used = 0;
 468                 ccw->count = sizeof(info->info_block->s);
 469         }
 470         ccw->cmd_code = CCW_CMD_SET_VQ;
 471         ccw->flags = 0;
 472         ccw->cda = (__u32)(unsigned long)(info->info_block);
 473         ret = ccw_io_helper(vcdev, ccw,
 474                             VIRTIO_CCW_DOING_SET_VQ | index);
 475         /*
 476          * -ENODEV isn't considered an error: The device is gone anyway.
 477          * This may happen on device detach.
 478          */
 479         if (ret && (ret != -ENODEV))
 480                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 481                          ret, index);
 482
 483         vring_del_virtqueue(vq);
 484         ccw_device_dma_free(vcdev->cdev, info->info_block,
 485                             sizeof(*info->info_block));
 486         kfree(info);
 487 }
 488
 489 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 490 {
 491         struct virtqueue *vq, *n;
 492         struct ccw1 *ccw;
 493         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 494
 495         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 496         if (!ccw)
 497                 return;
 498
 499         virtio_ccw_drop_indicator(vcdev, ccw);
 500
 501         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 502                 virtio_ccw_del_vq(vq, ccw);
 503
 504         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 505 }
 506
 507 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 508                                              int i, vq_callback_t *callback,
 509                                              const char *name, bool ctx,
 510                                              struct ccw1 *ccw)
 511 {
 512         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 513         int err;
 514         struct virtqueue *vq = NULL;
 515         struct virtio_ccw_vq_info *info;
 516         u64 queue;
 517         unsigned long flags;
 518         bool may_reduce;
 519
 520         /* Allocate queue. */
 521         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 522         if (!info) {
 523                 dev_warn(&vcdev->cdev->dev, "no info\n");
 524                 err = -ENOMEM;
 525                 goto out_err;
 526         }
 527         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 528                                                  sizeof(*info->info_block));
 529         if (!info->info_block) {
 530                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 531                 err = -ENOMEM;
 532                 goto out_err;
 533         }
 534         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 535         if (info->num < 0) {
 536                 err = info->num;
 537                 goto out_err;
 538         }
 539         may_reduce = vcdev->revision > 0;
 540         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 541                                     vdev, true, may_reduce, ctx,
 542                                     virtio_ccw_kvm_notify, callback, name);
 543
 544         if (!vq) {
 545                 /* For now, we fail if we can't get the requested size. */
 546                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 547                 err = -ENOMEM;
 548                 goto out_err;
 549         }
 550         /* it may have been reduced */
 551         info->num = virtqueue_get_vring_size(vq);
 552
 553         /* Register it with the host. */
 554         queue = virtqueue_get_desc_addr(vq);
 555         if (vcdev->revision == 0) {
 556                 info->info_block->l.queue = queue;
 557                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 558                 info->info_block->l.index = i;
 559                 info->info_block->l.num = info->num;
 560                 ccw->count = sizeof(info->info_block->l);
 561         } else {
 562                 info->info_block->s.desc = queue;
 563                 info->info_block->s.index = i;
 564                 info->info_block->s.num = info->num;
 565                 info->info_block->s.avail = (__u64)virtqueue_get_avail_addr(vq);
 566                 info->info_block->s.used = (__u64)virtqueue_get_used_addr(vq);
 567                 ccw->count = sizeof(info->info_block->s);
 568         }
 569         ccw->cmd_code = CCW_CMD_SET_VQ;
 570         ccw->flags = 0;
 571         ccw->cda = (__u32)(unsigned long)(info->info_block);
 572         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 573         if (err) {
 574                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 575                 goto out_err;
 576         }
 577
 578         info->vq = vq;
 579         vq->priv = info;
 580
 581         /* Save it to our list. */
 582         spin_lock_irqsave(&vcdev->lock, flags);
 583         list_add(&info->node, &vcdev->virtqueues);
 584         spin_unlock_irqrestore(&vcdev->lock, flags);
 585
 586         return vq;
 587
 588 out_err:
 589         if (vq)
 590                 vring_del_virtqueue(vq);
 591         if (info) {
 592                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 593                                     sizeof(*info->info_block));
 594         }
 595         kfree(info);
 596         return ERR_PTR(err);
 597 }
 598
 599 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 600                                            struct virtqueue *vqs[], int nvqs,
 601                                            struct ccw1 *ccw)
 602 {
 603         int ret;
 604         struct virtio_thinint_area *thinint_area = NULL;
 605         struct airq_info *info;
 606
 607         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 608                                              sizeof(*thinint_area));
 609         if (!thinint_area) {
 610                 ret = -ENOMEM;
 611                 goto out;
 612         }
 613         /* Try to get an indicator. */
 614         thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 615                                                      &thinint_area->bit_nr,
 616                                                      &vcdev->airq_info);
 617         if (!thinint_area->indicator) {
 618                 ret = -ENOSPC;
 619                 goto out;
 620         }
 621         info = vcdev->airq_info;
 622         thinint_area->summary_indicator =
 623                 (unsigned long) get_summary_indicator(info);
 624         thinint_area->isc = VIRTIO_AIRQ_ISC;
 625         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 626         ccw->flags = CCW_FLAG_SLI;
 627         ccw->count = sizeof(*thinint_area);
 628         ccw->cda = (__u32)(unsigned long)thinint_area;
 629         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 630         if (ret) {
 631                 if (ret == -EOPNOTSUPP) {
 632                         /*
 633                          * The host does not support adapter interrupts
 634                          * for virtio-ccw, stop trying.
 635                          */
 636                         virtio_ccw_use_airq = 0;
 637                         pr_info("Adapter interrupts unsupported on host\n");
 638                 } else
 639                         dev_warn(&vcdev->cdev->dev,
 640                                  "enabling adapter interrupts = %d\n", ret);
 641                 virtio_ccw_drop_indicators(vcdev);
 642         }
 643 out:
 644         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 645         return ret;
 646 }
 647
 648 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 649                                struct virtqueue *vqs[],
 650                                vq_callback_t *callbacks[],
 651                                const char * const names[],
 652                                const bool *ctx,
 653                                struct irq_affinity *desc)
 654 {
 655         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 656         unsigned long *indicatorp = NULL;
 657         int ret, i, queue_idx = 0;
 658         struct ccw1 *ccw;
 659
 660         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 661         if (!ccw)
 662                 return -ENOMEM;
 663
 664         for (i = 0; i < nvqs; ++i) {
 665                 if (!names[i]) {
 666                         vqs[i] = NULL;
 667                         continue;
 668                 }
 669
 670                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 671                                              names[i], ctx ? ctx[i] : false,
 672                                              ccw);
 673                 if (IS_ERR(vqs[i])) {
 674                         ret = PTR_ERR(vqs[i]);
 675                         vqs[i] = NULL;
 676                         goto out;
 677                 }
 678         }
 679         ret = -ENOMEM;
 680         /*
 681          * We need a data area under 2G to communicate. Our payload is
 682          * the address of the indicators.
 683         */
 684         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 685                                            sizeof(indicators(vcdev)));
 686         if (!indicatorp)
 687                 goto out;
 688         *indicatorp = (unsigned long) indicators(vcdev);
 689         if (vcdev->is_thinint) {
 690                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 691                 if (ret)
 692                         /* no error, just fall back to legacy interrupts */
 693                         vcdev->is_thinint = false;
 694         }
 695         if (!vcdev->is_thinint) {
 696                 /* Register queue indicators with host. */
 697                 *indicators(vcdev) = 0;
 698                 ccw->cmd_code = CCW_CMD_SET_IND;
 699                 ccw->flags = 0;
 700                 ccw->count = sizeof(indicators(vcdev));
 701                 ccw->cda = (__u32)(unsigned long) indicatorp;
 702                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 703                 if (ret)
 704                         goto out;
 705         }
 706         /* Register indicators2 with host for config changes */
 707         *indicatorp = (unsigned long) indicators2(vcdev);
 708         *indicators2(vcdev) = 0;
 709         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 710         ccw->flags = 0;
 711         ccw->count = sizeof(indicators2(vcdev));
 712         ccw->cda = (__u32)(unsigned long) indicatorp;
 713         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 714         if (ret)
 715                 goto out;
 716
 717         if (indicatorp)
 718                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 719                                     sizeof(indicators(vcdev)));
 720         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 721         return 0;
 722 out:
 723         if (indicatorp)
 724                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 725                                     sizeof(indicators(vcdev)));
 726         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 727         virtio_ccw_del_vqs(vdev);
 728         return ret;
 729 }
 730
 731 static void virtio_ccw_reset(struct virtio_device *vdev)
 732 {
 733         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 734         struct ccw1 *ccw;
 735
 736         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 737         if (!ccw)
 738                 return;
 739
 740         /* Zero status bits. */
 741         vcdev->dma_area->status = 0;
 742
 743         /* Send a reset ccw on device. */
 744         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 745         ccw->flags = 0;
 746         ccw->count = 0;
 747         ccw->cda = 0;
 748         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 749         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 750 }
 751
 752 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 753 {
 754         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 755         struct virtio_feature_desc *features;
 756         int ret;
 757         u64 rc;
 758         struct ccw1 *ccw;
 759
 760         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 761         if (!ccw)
 762                 return 0;
 763
 764         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 765         if (!features) {
 766                 rc = 0;
 767                 goto out_free;
 768         }
 769         /* Read the feature bits from the host. */
 770         features->index = 0;
 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) {
 777                 rc = 0;
 778                 goto out_free;
 779         }
 780
 781         rc = le32_to_cpu(features->features);
 782
 783         if (vcdev->revision == 0)
 784                 goto out_free;
 785
 786         /* Read second half of the feature bits from the host. */
 787         features->index = 1;
 788         ccw->cmd_code = CCW_CMD_READ_FEAT;
 789         ccw->flags = 0;
 790         ccw->count = sizeof(*features);
 791         ccw->cda = (__u32)(unsigned long)features;
 792         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 793         if (ret == 0)
 794                 rc |= (u64)le32_to_cpu(features->features) << 32;
 795
 796 out_free:
 797         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 798         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 799         return rc;
 800 }
 801
 802 static void ccw_transport_features(struct virtio_device *vdev)
 803 {
 804         /*
 805          * Currently nothing to do here.
 806          */
 807 }
 808
 809 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 810 {
 811         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 812         struct virtio_feature_desc *features;
 813         struct ccw1 *ccw;
 814         int ret;
 815
 816         if (vcdev->revision >= 1 &&
 817             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 818                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 819                         "but does not have VIRTIO_F_VERSION_1\n");
 820                 return -EINVAL;
 821         }
 822
 823         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 824         if (!ccw)
 825                 return -ENOMEM;
 826
 827         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 828         if (!features) {
 829                 ret = -ENOMEM;
 830                 goto out_free;
 831         }
 832         /* Give virtio_ring a chance to accept features. */
 833         vring_transport_features(vdev);
 834
 835         /* Give virtio_ccw a chance to accept features. */
 836         ccw_transport_features(vdev);
 837
 838         features->index = 0;
 839         features->features = cpu_to_le32((u32)vdev->features);
 840         /* Write the first half of the feature bits to the host. */
 841         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 842         ccw->flags = 0;
 843         ccw->count = sizeof(*features);
 844         ccw->cda = (__u32)(unsigned long)features;
 845         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 846         if (ret)
 847                 goto out_free;
 848
 849         if (vcdev->revision == 0)
 850                 goto out_free;
 851
 852         features->index = 1;
 853         features->features = cpu_to_le32(vdev->features >> 32);
 854         /* Write the second half of the feature bits to the host. */
 855         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 856         ccw->flags = 0;
 857         ccw->count = sizeof(*features);
 858         ccw->cda = (__u32)(unsigned long)features;
 859         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 860
 861 out_free:
 862         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 863         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 864
 865         return ret;
 866 }
 867
 868 static void virtio_ccw_get_config(struct virtio_device *vdev,
 869                                   unsigned int offset, void *buf, unsigned len)
 870 {
 871         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 872         int ret;
 873         struct ccw1 *ccw;
 874         void *config_area;
 875         unsigned long flags;
 876
 877         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 878         if (!ccw)
 879                 return;
 880
 881         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 882                                             VIRTIO_CCW_CONFIG_SIZE);
 883         if (!config_area)
 884                 goto out_free;
 885
 886         /* Read the config area from the host. */
 887         ccw->cmd_code = CCW_CMD_READ_CONF;
 888         ccw->flags = 0;
 889         ccw->count = offset + len;
 890         ccw->cda = (__u32)(unsigned long)config_area;
 891         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 892         if (ret)
 893                 goto out_free;
 894
 895         spin_lock_irqsave(&vcdev->lock, flags);
 896         memcpy(vcdev->config, config_area, offset + len);
 897         if (vcdev->config_ready < offset + len)
 898                 vcdev->config_ready = offset + len;
 899         spin_unlock_irqrestore(&vcdev->lock, flags);
 900         if (buf)
 901                 memcpy(buf, config_area + offset, len);
 902
 903 out_free:
 904         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 905         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 906 }
 907
 908 static void virtio_ccw_set_config(struct virtio_device *vdev,
 909                                   unsigned int offset, const void *buf,
 910                                   unsigned len)
 911 {
 912         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 913         struct ccw1 *ccw;
 914         void *config_area;
 915         unsigned long flags;
 916
 917         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 918         if (!ccw)
 919                 return;
 920
 921         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 922                                             VIRTIO_CCW_CONFIG_SIZE);
 923         if (!config_area)
 924                 goto out_free;
 925
 926         /* Make sure we don't overwrite fields. */
 927         if (vcdev->config_ready < offset)
 928                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 929         spin_lock_irqsave(&vcdev->lock, flags);
 930         memcpy(&vcdev->config[offset], buf, len);
 931         /* Write the config area to the host. */
 932         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 933         spin_unlock_irqrestore(&vcdev->lock, flags);
 934         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 935         ccw->flags = 0;
 936         ccw->count = offset + len;
 937         ccw->cda = (__u32)(unsigned long)config_area;
 938         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 939
 940 out_free:
 941         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 942         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 943 }
 944
 945 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 946 {
 947         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 948         u8 old_status = vcdev->dma_area->status;
 949         struct ccw1 *ccw;
 950
 951         if (vcdev->revision < 1)
 952                 return vcdev->dma_area->status;
 953
 954         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 955         if (!ccw)
 956                 return old_status;
 957
 958         ccw->cmd_code = CCW_CMD_READ_STATUS;
 959         ccw->flags = 0;
 960         ccw->count = sizeof(vcdev->dma_area->status);
 961         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 962         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 963 /*
 964  * If the channel program failed (should only happen if the device
 965  * was hotunplugged, and then we clean up via the machine check
 966  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 967  * return the old status, which is fine.
 968 */
 969         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 970
 971         return vcdev->dma_area->status;
 972 }
 973
 974 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 975 {
 976         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 977         u8 old_status = vcdev->dma_area->status;
 978         struct ccw1 *ccw;
 979         int ret;
 980
 981         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 982         if (!ccw)
 983                 return;
 984
 985         /* Write the status to the host. */
 986         vcdev->dma_area->status = status;
 987         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 988         ccw->flags = 0;
 989         ccw->count = sizeof(status);
 990         ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 991         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 992         /* Write failed? We assume status is unchanged. */
 993         if (ret)
 994                 vcdev->dma_area->status = old_status;
 995         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 996 }
 997
 998 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
 999 {
1000         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1001
1002         return dev_name(&vcdev->cdev->dev);
1003 }
1004
1005 static const struct virtio_config_ops virtio_ccw_config_ops = {
1006         .get_features = virtio_ccw_get_features,
1007         .finalize_features = virtio_ccw_finalize_features,
1008         .get = virtio_ccw_get_config,
1009         .set = virtio_ccw_set_config,
1010         .get_status = virtio_ccw_get_status,
1011         .set_status = virtio_ccw_set_status,
1012         .reset = virtio_ccw_reset,
1013         .find_vqs = virtio_ccw_find_vqs,
1014         .del_vqs = virtio_ccw_del_vqs,
1015         .bus_name = virtio_ccw_bus_name,
1016 };
1017
1018
1019 /*
1020  * ccw bus driver related functions
1021  */
1022
1023 static void virtio_ccw_release_dev(struct device *_d)
1024 {
1025         struct virtio_device *dev = dev_to_virtio(_d);
1026         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1027
1028         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1029                             sizeof(*vcdev->dma_area));
1030         kfree(vcdev);
1031 }
1032
1033 static int irb_is_error(struct irb *irb)
1034 {
1035         if (scsw_cstat(&irb->scsw) != 0)
1036                 return 1;
1037         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1038                 return 1;
1039         if (scsw_cc(&irb->scsw) != 0)
1040                 return 1;
1041         return 0;
1042 }
1043
1044 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1045                                               int index)
1046 {
1047         struct virtio_ccw_vq_info *info;
1048         unsigned long flags;
1049         struct virtqueue *vq;
1050
1051         vq = NULL;
1052         spin_lock_irqsave(&vcdev->lock, flags);
1053         list_for_each_entry(info, &vcdev->virtqueues, node) {
1054                 if (info->vq->index == index) {
1055                         vq = info->vq;
1056                         break;
1057                 }
1058         }
1059         spin_unlock_irqrestore(&vcdev->lock, flags);
1060         return vq;
1061 }
1062
1063 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1064                                       __u32 activity)
1065 {
1066         if (vcdev->curr_io & activity) {
1067                 switch (activity) {
1068                 case VIRTIO_CCW_DOING_READ_FEAT:
1069                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1070                 case VIRTIO_CCW_DOING_READ_CONFIG:
1071                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1072                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1073                 case VIRTIO_CCW_DOING_READ_STATUS:
1074                 case VIRTIO_CCW_DOING_SET_VQ:
1075                 case VIRTIO_CCW_DOING_SET_IND:
1076                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1077                 case VIRTIO_CCW_DOING_RESET:
1078                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1079                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1080                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1081                         vcdev->curr_io &= ~activity;
1082                         wake_up(&vcdev->wait_q);
1083                         break;
1084                 default:
1085                         /* don't know what to do... */
1086                         dev_warn(&vcdev->cdev->dev,
1087                                  "Suspicious activity '%08x'\n", activity);
1088                         WARN_ON(1);
1089                         break;
1090                 }
1091         }
1092 }
1093
1094 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1095                                    unsigned long intparm,
1096                                    struct irb *irb)
1097 {
1098         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1099         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1100         int i;
1101         struct virtqueue *vq;
1102
1103         if (!vcdev)
1104                 return;
1105         if (IS_ERR(irb)) {
1106                 vcdev->err = PTR_ERR(irb);
1107                 virtio_ccw_check_activity(vcdev, activity);
1108                 /* Don't poke around indicators, something's wrong. */
1109                 return;
1110         }
1111         /* Check if it's a notification from the host. */
1112         if ((intparm == 0) &&
1113             (scsw_stctl(&irb->scsw) ==
1114              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1115                 /* OK */
1116         }
1117         if (irb_is_error(irb)) {
1118                 /* Command reject? */
1119                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1120                     (irb->ecw[0] & SNS0_CMD_REJECT))
1121                         vcdev->err = -EOPNOTSUPP;
1122                 else
1123                         /* Map everything else to -EIO. */
1124                         vcdev->err = -EIO;
1125         }
1126         virtio_ccw_check_activity(vcdev, activity);
1127         for_each_set_bit(i, indicators(vcdev),
1128                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1129                 /* The bit clear must happen before the vring kick. */
1130                 clear_bit(i, indicators(vcdev));
1131                 barrier();
1132                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1133                 vring_interrupt(0, vq);
1134         }
1135         if (test_bit(0, indicators2(vcdev))) {
1136                 virtio_config_changed(&vcdev->vdev);
1137                 clear_bit(0, indicators2(vcdev));
1138         }
1139 }
1140
1141 /*
1142  * We usually want to autoonline all devices, but give the admin
1143  * a way to exempt devices from this.
1144  */
1145 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1146                      (8*sizeof(long)))
1147 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1148
1149 static char *no_auto = "";
1150
1151 module_param(no_auto, charp, 0444);
1152 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1153
1154 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1155 {
1156         struct ccw_dev_id id;
1157
1158         ccw_device_get_id(cdev, &id);
1159         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1160                 return 0;
1161         return 1;
1162 }
1163
1164 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1165 {
1166         struct ccw_device *cdev = data;
1167         int ret;
1168
1169         ret = ccw_device_set_online(cdev);
1170         if (ret)
1171                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1172 }
1173
1174 static int virtio_ccw_probe(struct ccw_device *cdev)
1175 {
1176         cdev->handler = virtio_ccw_int_handler;
1177
1178         if (virtio_ccw_check_autoonline(cdev))
1179                 async_schedule(virtio_ccw_auto_online, cdev);
1180         return 0;
1181 }
1182
1183 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1184 {
1185         unsigned long flags;
1186         struct virtio_ccw_device *vcdev;
1187
1188         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1189         vcdev = dev_get_drvdata(&cdev->dev);
1190         if (!vcdev || vcdev->going_away) {
1191                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1192                 return NULL;
1193         }
1194         vcdev->going_away = true;
1195         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1196         return vcdev;
1197 }
1198
1199 static void virtio_ccw_remove(struct ccw_device *cdev)
1200 {
1201         unsigned long flags;
1202         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1203
1204         if (vcdev && cdev->online) {
1205                 if (vcdev->device_lost)
1206                         virtio_break_device(&vcdev->vdev);
1207                 unregister_virtio_device(&vcdev->vdev);
1208                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1209                 dev_set_drvdata(&cdev->dev, NULL);
1210                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1211         }
1212         cdev->handler = NULL;
1213 }
1214
1215 static int virtio_ccw_offline(struct ccw_device *cdev)
1216 {
1217         unsigned long flags;
1218         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1219
1220         if (!vcdev)
1221                 return 0;
1222         if (vcdev->device_lost)
1223                 virtio_break_device(&vcdev->vdev);
1224         unregister_virtio_device(&vcdev->vdev);
1225         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1226         dev_set_drvdata(&cdev->dev, NULL);
1227         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1228         return 0;
1229 }
1230
1231 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1232 {
1233         struct virtio_rev_info *rev;
1234         struct ccw1 *ccw;
1235         int ret;
1236
1237         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1238         if (!ccw)
1239                 return -ENOMEM;
1240         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1241         if (!rev) {
1242                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1243                 return -ENOMEM;
1244         }
1245
1246         /* Set transport revision */
1247         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1248         ccw->flags = 0;
1249         ccw->count = sizeof(*rev);
1250         ccw->cda = (__u32)(unsigned long)rev;
1251
1252         vcdev->revision = VIRTIO_CCW_REV_MAX;
1253         do {
1254                 rev->revision = vcdev->revision;
1255                 /* none of our supported revisions carry payload */
1256                 rev->length = 0;
1257                 ret = ccw_io_helper(vcdev, ccw,
1258                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1259                 if (ret == -EOPNOTSUPP) {
1260                         if (vcdev->revision == 0)
1261                                 /*
1262                                  * The host device does not support setting
1263                                  * the revision: let's operate it in legacy
1264                                  * mode.
1265                                  */
1266                                 ret = 0;
1267                         else
1268                                 vcdev->revision--;
1269                 }
1270         } while (ret == -EOPNOTSUPP);
1271
1272         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1273         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1274         return ret;
1275 }
1276
1277 static int virtio_ccw_online(struct ccw_device *cdev)
1278 {
1279         int ret;
1280         struct virtio_ccw_device *vcdev;
1281         unsigned long flags;
1282
1283         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1284         if (!vcdev) {
1285                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1286                 ret = -ENOMEM;
1287                 goto out_free;
1288         }
1289         vcdev->vdev.dev.parent = &cdev->dev;
1290         vcdev->cdev = cdev;
1291         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1292                                                 sizeof(*vcdev->dma_area));
1293         if (!vcdev->dma_area) {
1294                 ret = -ENOMEM;
1295                 goto out_free;
1296         }
1297
1298         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1299
1300         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1301         vcdev->vdev.config = &virtio_ccw_config_ops;
1302         init_waitqueue_head(&vcdev->wait_q);
1303         INIT_LIST_HEAD(&vcdev->virtqueues);
1304         spin_lock_init(&vcdev->lock);
1305         mutex_init(&vcdev->io_lock);
1306
1307         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1308         dev_set_drvdata(&cdev->dev, vcdev);
1309         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1310         vcdev->vdev.id.vendor = cdev->id.cu_type;
1311         vcdev->vdev.id.device = cdev->id.cu_model;
1312
1313         ret = virtio_ccw_set_transport_rev(vcdev);
1314         if (ret)
1315                 goto out_free;
1316
1317         ret = register_virtio_device(&vcdev->vdev);
1318         if (ret) {
1319                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1320                          ret);
1321                 goto out_put;
1322         }
1323         return 0;
1324 out_put:
1325         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1326         dev_set_drvdata(&cdev->dev, NULL);
1327         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1328         put_device(&vcdev->vdev.dev);
1329         return ret;
1330 out_free:
1331         if (vcdev) {
1332                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1333                                     sizeof(*vcdev->dma_area));
1334         }
1335         kfree(vcdev);
1336         return ret;
1337 }
1338
1339 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1340 {
1341         int rc;
1342         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1343
1344         /*
1345          * Make sure vcdev is set
1346          * i.e. set_offline/remove callback not already running
1347          */
1348         if (!vcdev)
1349                 return NOTIFY_DONE;
1350
1351         switch (event) {
1352         case CIO_GONE:
1353                 vcdev->device_lost = true;
1354                 rc = NOTIFY_DONE;
1355                 break;
1356         case CIO_OPER:
1357                 rc = NOTIFY_OK;
1358                 break;
1359         default:
1360                 rc = NOTIFY_DONE;
1361                 break;
1362         }
1363         return rc;
1364 }
1365
1366 static struct ccw_device_id virtio_ids[] = {
1367         { CCW_DEVICE(0x3832, 0) },
1368         {},
1369 };
1370
1371 #ifdef CONFIG_PM_SLEEP
1372 static int virtio_ccw_freeze(struct ccw_device *cdev)
1373 {
1374         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1375
1376         return virtio_device_freeze(&vcdev->vdev);
1377 }
1378
1379 static int virtio_ccw_restore(struct ccw_device *cdev)
1380 {
1381         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1382         int ret;
1383
1384         ret = virtio_ccw_set_transport_rev(vcdev);
1385         if (ret)
1386                 return ret;
1387
1388         return virtio_device_restore(&vcdev->vdev);
1389 }
1390 #endif
1391
1392 static struct ccw_driver virtio_ccw_driver = {
1393         .driver = {
1394                 .owner = THIS_MODULE,
1395                 .name = "virtio_ccw",
1396         },
1397         .ids = virtio_ids,
1398         .probe = virtio_ccw_probe,
1399         .remove = virtio_ccw_remove,
1400         .set_offline = virtio_ccw_offline,
1401         .set_online = virtio_ccw_online,
1402         .notify = virtio_ccw_cio_notify,
1403         .int_class = IRQIO_VIR,
1404 #ifdef CONFIG_PM_SLEEP
1405         .freeze = virtio_ccw_freeze,
1406         .thaw = virtio_ccw_restore,
1407         .restore = virtio_ccw_restore,
1408 #endif
1409 };
1410
1411 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1412                            int max_digit, int max_val)
1413 {
1414         int diff;
1415
1416         diff = 0;
1417         *val = 0;
1418
1419         while (diff <= max_digit) {
1420                 int value = hex_to_bin(**cp);
1421
1422                 if (value < 0)
1423                         break;
1424                 *val = *val * 16 + value;
1425                 (*cp)++;
1426                 diff++;
1427         }
1428
1429         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1430                 return 1;
1431
1432         return 0;
1433 }
1434
1435 static int __init parse_busid(char *str, unsigned int *cssid,
1436                               unsigned int *ssid, unsigned int *devno)
1437 {
1438         char *str_work;
1439         int rc, ret;
1440
1441         rc = 1;
1442
1443         if (*str == '\0')
1444                 goto out;
1445
1446         str_work = str;
1447         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1448         if (ret || (str_work[0] != '.'))
1449                 goto out;
1450         str_work++;
1451         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1452         if (ret || (str_work[0] != '.'))
1453                 goto out;
1454         str_work++;
1455         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1456         if (ret || (str_work[0] != '\0'))
1457                 goto out;
1458
1459         rc = 0;
1460 out:
1461         return rc;
1462 }
1463
1464 static void __init no_auto_parse(void)
1465 {
1466         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1467         char *parm, *str;
1468         int rc;
1469
1470         str = no_auto;
1471         while ((parm = strsep(&str, ","))) {
1472                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1473                                  &from_ssid, &from);
1474                 if (rc)
1475                         continue;
1476                 if (parm != NULL) {
1477                         rc = parse_busid(parm, &to_cssid,
1478                                          &to_ssid, &to);
1479                         if ((from_ssid > to_ssid) ||
1480                             ((from_ssid == to_ssid) && (from > to)))
1481                                 rc = -EINVAL;
1482                 } else {
1483                         to_cssid = from_cssid;
1484                         to_ssid = from_ssid;
1485                         to = from;
1486                 }
1487                 if (rc)
1488                         continue;
1489                 while ((from_ssid < to_ssid) ||
1490                        ((from_ssid == to_ssid) && (from <= to))) {
1491                         set_bit(from, devs_no_auto[from_ssid]);
1492                         from++;
1493                         if (from > __MAX_SUBCHANNEL) {
1494                                 from_ssid++;
1495                                 from = 0;
1496                         }
1497                 }
1498         }
1499 }
1500
1501 static int __init virtio_ccw_init(void)
1502 {
1503         int rc;
1504
1505         /* parse no_auto string before we do anything further */
1506         no_auto_parse();
1507
1508         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1509         if (!summary_indicators)
1510                 return -ENOMEM;
1511         rc = ccw_driver_register(&virtio_ccw_driver);
1512         if (rc)
1513                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1514         return rc;
1515 }
1516 device_initcall(virtio_ccw_init);