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 <[email protected]>
   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 #include <asm/tpi.h>
  37
  38 /*
  39  * virtio related functions
  40  */
  41
  42 struct vq_config_block {
  43         __u16 index;
  44         __u16 num;
  45 } __packed;
  46
  47 #define VIRTIO_CCW_CONFIG_SIZE 0x100
  48 /* same as PCI config space size, should be enough for all drivers */
  49
  50 struct vcdev_dma_area {
  51         unsigned long indicators;
  52         unsigned long indicators2;
  53         struct vq_config_block config_block;
  54         __u8 status;
  55 };
  56
  57 struct virtio_ccw_device {
  58         struct virtio_device vdev;
  59         __u8 config[VIRTIO_CCW_CONFIG_SIZE];
  60         struct ccw_device *cdev;
  61         __u32 curr_io;
  62         int err;
  63         unsigned int revision; /* Transport revision */
  64         wait_queue_head_t wait_q;
  65         spinlock_t lock;
  66         rwlock_t irq_lock;
  67         struct mutex io_lock; /* Serializes I/O requests */
  68         struct list_head virtqueues;
  69         bool is_thinint;
  70         bool going_away;
  71         bool device_lost;
  72         unsigned int config_ready;
  73         void *airq_info;
  74         struct vcdev_dma_area *dma_area;
  75 };
  76
  77 static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  78 {
  79         return &vcdev->dma_area->indicators;
  80 }
  81
  82 static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  83 {
  84         return &vcdev->dma_area->indicators2;
  85 }
  86
  87 struct vq_info_block_legacy {
  88         __u64 queue;
  89         __u32 align;
  90         __u16 index;
  91         __u16 num;
  92 } __packed;
  93
  94 struct vq_info_block {
  95         __u64 desc;
  96         __u32 res0;
  97         __u16 index;
  98         __u16 num;
  99         __u64 avail;
 100         __u64 used;
 101 } __packed;
 102
 103 struct virtio_feature_desc {
 104         __le32 features;
 105         __u8 index;
 106 } __packed;
 107
 108 struct virtio_thinint_area {
 109         unsigned long summary_indicator;
 110         unsigned long indicator;
 111         u64 bit_nr;
 112         u8 isc;
 113 } __packed;
 114
 115 struct virtio_rev_info {
 116         __u16 revision;
 117         __u16 length;
 118         __u8 data[];
 119 };
 120
 121 /* the highest virtio-ccw revision we support */
 122 #define VIRTIO_CCW_REV_MAX 2
 123
 124 struct virtio_ccw_vq_info {
 125         struct virtqueue *vq;
 126         int num;
 127         union {
 128                 struct vq_info_block s;
 129                 struct vq_info_block_legacy l;
 130         } *info_block;
 131         int bit_nr;
 132         struct list_head node;
 133         long cookie;
 134 };
 135
 136 #define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
 137
 138 #define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
 139 #define MAX_AIRQ_AREAS 20
 140
 141 static int virtio_ccw_use_airq = 1;
 142
 143 struct airq_info {
 144         rwlock_t lock;
 145         u8 summary_indicator_idx;
 146         struct airq_struct airq;
 147         struct airq_iv *aiv;
 148 };
 149 static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 150 static DEFINE_MUTEX(airq_areas_lock);
 151
 152 static u8 *summary_indicators;
 153
 154 static inline u8 *get_summary_indicator(struct airq_info *info)
 155 {
 156         return summary_indicators + info->summary_indicator_idx;
 157 }
 158
 159 #define CCW_CMD_SET_VQ 0x13
 160 #define CCW_CMD_VDEV_RESET 0x33
 161 #define CCW_CMD_SET_IND 0x43
 162 #define CCW_CMD_SET_CONF_IND 0x53
 163 #define CCW_CMD_READ_FEAT 0x12
 164 #define CCW_CMD_WRITE_FEAT 0x11
 165 #define CCW_CMD_READ_CONF 0x22
 166 #define CCW_CMD_WRITE_CONF 0x21
 167 #define CCW_CMD_WRITE_STATUS 0x31
 168 #define CCW_CMD_READ_VQ_CONF 0x32
 169 #define CCW_CMD_READ_STATUS 0x72
 170 #define CCW_CMD_SET_IND_ADAPTER 0x73
 171 #define CCW_CMD_SET_VIRTIO_REV 0x83
 172
 173 #define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 174 #define VIRTIO_CCW_DOING_RESET 0x00040000
 175 #define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 176 #define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 177 #define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 178 #define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 179 #define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 180 #define VIRTIO_CCW_DOING_SET_IND 0x01000000
 181 #define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 182 #define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 183 #define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 184 #define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 185 #define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 186 #define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 187
 188 static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 189 {
 190         return container_of(vdev, struct virtio_ccw_device, vdev);
 191 }
 192
 193 static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 194 {
 195         unsigned long i, flags;
 196
 197         write_lock_irqsave(&info->lock, flags);
 198         for (i = 0; i < airq_iv_end(info->aiv); i++) {
 199                 if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 200                         airq_iv_free_bit(info->aiv, i);
 201                         airq_iv_set_ptr(info->aiv, i, 0);
 202                         break;
 203                 }
 204         }
 205         write_unlock_irqrestore(&info->lock, flags);
 206 }
 207
 208 static void virtio_airq_handler(struct airq_struct *airq,
 209                                 struct tpi_info *tpi_info)
 210 {
 211         struct airq_info *info = container_of(airq, struct airq_info, airq);
 212         unsigned long ai;
 213
 214         inc_irq_stat(IRQIO_VAI);
 215         read_lock(&info->lock);
 216         /* Walk through indicators field, summary indicator active. */
 217         for (ai = 0;;) {
 218                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 219                 if (ai == -1UL)
 220                         break;
 221                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 222         }
 223         *(get_summary_indicator(info)) = 0;
 224         smp_wmb();
 225         /* Walk through indicators field, summary indicator not active. */
 226         for (ai = 0;;) {
 227                 ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 228                 if (ai == -1UL)
 229                         break;
 230                 vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 231         }
 232         read_unlock(&info->lock);
 233 }
 234
 235 static struct airq_info *new_airq_info(int index)
 236 {
 237         struct airq_info *info;
 238         int rc;
 239
 240         info = kzalloc(sizeof(*info), GFP_KERNEL);
 241         if (!info)
 242                 return NULL;
 243         rwlock_init(&info->lock);
 244         info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 245                                    | AIRQ_IV_CACHELINE, NULL);
 246         if (!info->aiv) {
 247                 kfree(info);
 248                 return NULL;
 249         }
 250         info->airq.handler = virtio_airq_handler;
 251         info->summary_indicator_idx = index;
 252         info->airq.lsi_ptr = get_summary_indicator(info);
 253         info->airq.lsi_mask = 0xff;
 254         info->airq.isc = VIRTIO_AIRQ_ISC;
 255         rc = register_adapter_interrupt(&info->airq);
 256         if (rc) {
 257                 airq_iv_release(info->aiv);
 258                 kfree(info);
 259                 return NULL;
 260         }
 261         return info;
 262 }
 263
 264 static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 265                                         u64 *first, void **airq_info)
 266 {
 267         int i, j;
 268         struct airq_info *info;
 269         unsigned long indicator_addr = 0;
 270         unsigned long bit, flags;
 271
 272         for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 273                 mutex_lock(&airq_areas_lock);
 274                 if (!airq_areas[i])
 275                         airq_areas[i] = new_airq_info(i);
 276                 info = airq_areas[i];
 277                 mutex_unlock(&airq_areas_lock);
 278                 if (!info)
 279                         return 0;
 280                 write_lock_irqsave(&info->lock, flags);
 281                 bit = airq_iv_alloc(info->aiv, nvqs);
 282                 if (bit == -1UL) {
 283                         /* Not enough vacancies. */
 284                         write_unlock_irqrestore(&info->lock, flags);
 285                         continue;
 286                 }
 287                 *first = bit;
 288                 *airq_info = info;
 289                 indicator_addr = (unsigned long)info->aiv->vector;
 290                 for (j = 0; j < nvqs; j++) {
 291                         airq_iv_set_ptr(info->aiv, bit + j,
 292                                         (unsigned long)vqs[j]);
 293                 }
 294                 write_unlock_irqrestore(&info->lock, flags);
 295         }
 296         return indicator_addr;
 297 }
 298
 299 static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 300 {
 301         struct virtio_ccw_vq_info *info;
 302
 303         if (!vcdev->airq_info)
 304                 return;
 305         list_for_each_entry(info, &vcdev->virtqueues, node)
 306                 drop_airq_indicator(info->vq, vcdev->airq_info);
 307 }
 308
 309 static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 310 {
 311         unsigned long flags;
 312         __u32 ret;
 313
 314         spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 315         if (vcdev->err)
 316                 ret = 0;
 317         else
 318                 ret = vcdev->curr_io & flag;
 319         spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 320         return ret;
 321 }
 322
 323 static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 324                          struct ccw1 *ccw, __u32 intparm)
 325 {
 326         int ret;
 327         unsigned long flags;
 328         int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 329
 330         mutex_lock(&vcdev->io_lock);
 331         do {
 332                 spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 333                 ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 334                 if (!ret) {
 335                         if (!vcdev->curr_io)
 336                                 vcdev->err = 0;
 337                         vcdev->curr_io |= flag;
 338                 }
 339                 spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 340                 cpu_relax();
 341         } while (ret == -EBUSY);
 342         wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 343         ret = ret ? ret : vcdev->err;
 344         mutex_unlock(&vcdev->io_lock);
 345         return ret;
 346 }
 347
 348 static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 349                                       struct ccw1 *ccw)
 350 {
 351         int ret;
 352         unsigned long *indicatorp = NULL;
 353         struct virtio_thinint_area *thinint_area = NULL;
 354         struct airq_info *airq_info = vcdev->airq_info;
 355
 356         if (vcdev->is_thinint) {
 357                 thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 358                                                      sizeof(*thinint_area));
 359                 if (!thinint_area)
 360                         return;
 361                 thinint_area->summary_indicator =
 362                         (unsigned long) get_summary_indicator(airq_info);
 363                 thinint_area->isc = VIRTIO_AIRQ_ISC;
 364                 ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 365                 ccw->count = sizeof(*thinint_area);
 366                 ccw->cda = (__u32)virt_to_phys(thinint_area);
 367         } else {
 368                 /* payload is the address of the indicators */
 369                 indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 370                                                    sizeof(indicators(vcdev)));
 371                 if (!indicatorp)
 372                         return;
 373                 *indicatorp = 0;
 374                 ccw->cmd_code = CCW_CMD_SET_IND;
 375                 ccw->count = sizeof(indicators(vcdev));
 376                 ccw->cda = (__u32)virt_to_phys(indicatorp);
 377         }
 378         /* Deregister indicators from host. */
 379         *indicators(vcdev) = 0;
 380         ccw->flags = 0;
 381         ret = ccw_io_helper(vcdev, ccw,
 382                             vcdev->is_thinint ?
 383                             VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 384                             VIRTIO_CCW_DOING_SET_IND);
 385         if (ret && (ret != -ENODEV))
 386                 dev_info(&vcdev->cdev->dev,
 387                          "Failed to deregister indicators (%d)\n", ret);
 388         else if (vcdev->is_thinint)
 389                 virtio_ccw_drop_indicators(vcdev);
 390         ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
 391         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 392 }
 393
 394 static inline bool virtio_ccw_do_kvm_notify(struct virtqueue *vq, u32 data)
 395 {
 396         struct virtio_ccw_vq_info *info = vq->priv;
 397         struct virtio_ccw_device *vcdev;
 398         struct subchannel_id schid;
 399
 400         vcdev = to_vc_device(info->vq->vdev);
 401         ccw_device_get_schid(vcdev->cdev, &schid);
 402         BUILD_BUG_ON(sizeof(struct subchannel_id) != sizeof(unsigned int));
 403         info->cookie = kvm_hypercall3(KVM_S390_VIRTIO_CCW_NOTIFY,
 404                                       *((unsigned int *)&schid),
 405                                       data, info->cookie);
 406         if (info->cookie < 0)
 407                 return false;
 408         return true;
 409 }
 410
 411 static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 412 {
 413         return virtio_ccw_do_kvm_notify(vq, vq->index);
 414 }
 415
 416 static bool virtio_ccw_kvm_notify_with_data(struct virtqueue *vq)
 417 {
 418         return virtio_ccw_do_kvm_notify(vq, vring_notification_data(vq));
 419 }
 420
 421 static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 422                                    struct ccw1 *ccw, int index)
 423 {
 424         int ret;
 425
 426         vcdev->dma_area->config_block.index = index;
 427         ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 428         ccw->flags = 0;
 429         ccw->count = sizeof(struct vq_config_block);
 430         ccw->cda = (__u32)virt_to_phys(&vcdev->dma_area->config_block);
 431         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 432         if (ret)
 433                 return ret;
 434         return vcdev->dma_area->config_block.num ?: -ENOENT;
 435 }
 436
 437 static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 438 {
 439         struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 440         struct virtio_ccw_vq_info *info = vq->priv;
 441         unsigned long flags;
 442         int ret;
 443         unsigned int index = vq->index;
 444
 445         /* Remove from our list. */
 446         spin_lock_irqsave(&vcdev->lock, flags);
 447         list_del(&info->node);
 448         spin_unlock_irqrestore(&vcdev->lock, flags);
 449
 450         /* Release from host. */
 451         if (vcdev->revision == 0) {
 452                 info->info_block->l.queue = 0;
 453                 info->info_block->l.align = 0;
 454                 info->info_block->l.index = index;
 455                 info->info_block->l.num = 0;
 456                 ccw->count = sizeof(info->info_block->l);
 457         } else {
 458                 info->info_block->s.desc = 0;
 459                 info->info_block->s.index = index;
 460                 info->info_block->s.num = 0;
 461                 info->info_block->s.avail = 0;
 462                 info->info_block->s.used = 0;
 463                 ccw->count = sizeof(info->info_block->s);
 464         }
 465         ccw->cmd_code = CCW_CMD_SET_VQ;
 466         ccw->flags = 0;
 467         ccw->cda = (__u32)virt_to_phys(info->info_block);
 468         ret = ccw_io_helper(vcdev, ccw,
 469                             VIRTIO_CCW_DOING_SET_VQ | index);
 470         /*
 471          * -ENODEV isn't considered an error: The device is gone anyway.
 472          * This may happen on device detach.
 473          */
 474         if (ret && (ret != -ENODEV))
 475                 dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 476                          ret, index);
 477
 478         vring_del_virtqueue(vq);
 479         ccw_device_dma_free(vcdev->cdev, info->info_block,
 480                             sizeof(*info->info_block));
 481         kfree(info);
 482 }
 483
 484 static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 485 {
 486         struct virtqueue *vq, *n;
 487         struct ccw1 *ccw;
 488         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 489
 490         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 491         if (!ccw)
 492                 return;
 493
 494         virtio_ccw_drop_indicator(vcdev, ccw);
 495
 496         list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 497                 virtio_ccw_del_vq(vq, ccw);
 498
 499         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 500 }
 501
 502 static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 503                                              int i, vq_callback_t *callback,
 504                                              const char *name, bool ctx,
 505                                              struct ccw1 *ccw)
 506 {
 507         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 508         bool (*notify)(struct virtqueue *vq);
 509         int err;
 510         struct virtqueue *vq = NULL;
 511         struct virtio_ccw_vq_info *info;
 512         u64 queue;
 513         unsigned long flags;
 514         bool may_reduce;
 515
 516         if (__virtio_test_bit(vdev, VIRTIO_F_NOTIFICATION_DATA))
 517                 notify = virtio_ccw_kvm_notify_with_data;
 518         else
 519                 notify = virtio_ccw_kvm_notify;
 520
 521         /* Allocate queue. */
 522         info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 523         if (!info) {
 524                 dev_warn(&vcdev->cdev->dev, "no info\n");
 525                 err = -ENOMEM;
 526                 goto out_err;
 527         }
 528         info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 529                                                  sizeof(*info->info_block));
 530         if (!info->info_block) {
 531                 dev_warn(&vcdev->cdev->dev, "no info block\n");
 532                 err = -ENOMEM;
 533                 goto out_err;
 534         }
 535         info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 536         if (info->num < 0) {
 537                 err = info->num;
 538                 goto out_err;
 539         }
 540         may_reduce = vcdev->revision > 0;
 541         vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 542                                     vdev, true, may_reduce, ctx,
 543                                     notify, callback, name);
 544
 545         if (!vq) {
 546                 /* For now, we fail if we can't get the requested size. */
 547                 dev_warn(&vcdev->cdev->dev, "no vq\n");
 548                 err = -ENOMEM;
 549                 goto out_err;
 550         }
 551
 552         vq->num_max = info->num;
 553
 554         /* it may have been reduced */
 555         info->num = virtqueue_get_vring_size(vq);
 556
 557         /* Register it with the host. */
 558         queue = virtqueue_get_desc_addr(vq);
 559         if (vcdev->revision == 0) {
 560                 info->info_block->l.queue = queue;
 561                 info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
 562                 info->info_block->l.index = i;
 563                 info->info_block->l.num = info->num;
 564                 ccw->count = sizeof(info->info_block->l);
 565         } else {
 566                 info->info_block->s.desc = queue;
 567                 info->info_block->s.index = i;
 568                 info->info_block->s.num = info->num;
 569                 info->info_block->s.avail = (__u64)virtqueue_get_avail_addr(vq);
 570                 info->info_block->s.used = (__u64)virtqueue_get_used_addr(vq);
 571                 ccw->count = sizeof(info->info_block->s);
 572         }
 573         ccw->cmd_code = CCW_CMD_SET_VQ;
 574         ccw->flags = 0;
 575         ccw->cda = (__u32)virt_to_phys(info->info_block);
 576         err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
 577         if (err) {
 578                 dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
 579                 goto out_err;
 580         }
 581
 582         info->vq = vq;
 583         vq->priv = info;
 584
 585         /* Save it to our list. */
 586         spin_lock_irqsave(&vcdev->lock, flags);
 587         list_add(&info->node, &vcdev->virtqueues);
 588         spin_unlock_irqrestore(&vcdev->lock, flags);
 589
 590         return vq;
 591
 592 out_err:
 593         if (vq)
 594                 vring_del_virtqueue(vq);
 595         if (info) {
 596                 ccw_device_dma_free(vcdev->cdev, info->info_block,
 597                                     sizeof(*info->info_block));
 598         }
 599         kfree(info);
 600         return ERR_PTR(err);
 601 }
 602
 603 static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
 604                                            struct virtqueue *vqs[], int nvqs,
 605                                            struct ccw1 *ccw)
 606 {
 607         int ret;
 608         struct virtio_thinint_area *thinint_area = NULL;
 609         unsigned long indicator_addr;
 610         struct airq_info *info;
 611
 612         thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 613                                              sizeof(*thinint_area));
 614         if (!thinint_area) {
 615                 ret = -ENOMEM;
 616                 goto out;
 617         }
 618         /* Try to get an indicator. */
 619         indicator_addr = get_airq_indicator(vqs, nvqs,
 620                                             &thinint_area->bit_nr,
 621                                             &vcdev->airq_info);
 622         if (!indicator_addr) {
 623                 ret = -ENOSPC;
 624                 goto out;
 625         }
 626         thinint_area->indicator = virt_to_phys((void *)indicator_addr);
 627         info = vcdev->airq_info;
 628         thinint_area->summary_indicator =
 629                 virt_to_phys(get_summary_indicator(info));
 630         thinint_area->isc = VIRTIO_AIRQ_ISC;
 631         ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 632         ccw->flags = CCW_FLAG_SLI;
 633         ccw->count = sizeof(*thinint_area);
 634         ccw->cda = (__u32)virt_to_phys(thinint_area);
 635         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 636         if (ret) {
 637                 if (ret == -EOPNOTSUPP) {
 638                         /*
 639                          * The host does not support adapter interrupts
 640                          * for virtio-ccw, stop trying.
 641                          */
 642                         virtio_ccw_use_airq = 0;
 643                         pr_info("Adapter interrupts unsupported on host\n");
 644                 } else
 645                         dev_warn(&vcdev->cdev->dev,
 646                                  "enabling adapter interrupts = %d\n", ret);
 647                 virtio_ccw_drop_indicators(vcdev);
 648         }
 649 out:
 650         ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 651         return ret;
 652 }
 653
 654 static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 655                                struct virtqueue *vqs[],
 656                                vq_callback_t *callbacks[],
 657                                const char * const names[],
 658                                const bool *ctx,
 659                                struct irq_affinity *desc)
 660 {
 661         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 662         unsigned long *indicatorp = NULL;
 663         int ret, i, queue_idx = 0;
 664         struct ccw1 *ccw;
 665
 666         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 667         if (!ccw)
 668                 return -ENOMEM;
 669
 670         for (i = 0; i < nvqs; ++i) {
 671                 if (!names[i]) {
 672                         vqs[i] = NULL;
 673                         continue;
 674                 }
 675
 676                 vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 677                                              names[i], ctx ? ctx[i] : false,
 678                                              ccw);
 679                 if (IS_ERR(vqs[i])) {
 680                         ret = PTR_ERR(vqs[i]);
 681                         vqs[i] = NULL;
 682                         goto out;
 683                 }
 684         }
 685         ret = -ENOMEM;
 686         /*
 687          * We need a data area under 2G to communicate. Our payload is
 688          * the address of the indicators.
 689         */
 690         indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 691                                            sizeof(indicators(vcdev)));
 692         if (!indicatorp)
 693                 goto out;
 694         *indicatorp = (unsigned long) indicators(vcdev);
 695         if (vcdev->is_thinint) {
 696                 ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 697                 if (ret)
 698                         /* no error, just fall back to legacy interrupts */
 699                         vcdev->is_thinint = false;
 700         }
 701         if (!vcdev->is_thinint) {
 702                 /* Register queue indicators with host. */
 703                 *indicators(vcdev) = 0;
 704                 ccw->cmd_code = CCW_CMD_SET_IND;
 705                 ccw->flags = 0;
 706                 ccw->count = sizeof(indicators(vcdev));
 707                 ccw->cda = (__u32)virt_to_phys(indicatorp);
 708                 ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 709                 if (ret)
 710                         goto out;
 711         }
 712         /* Register indicators2 with host for config changes */
 713         *indicatorp = (unsigned long) indicators2(vcdev);
 714         *indicators2(vcdev) = 0;
 715         ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 716         ccw->flags = 0;
 717         ccw->count = sizeof(indicators2(vcdev));
 718         ccw->cda = (__u32)virt_to_phys(indicatorp);
 719         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 720         if (ret)
 721                 goto out;
 722
 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         return 0;
 728 out:
 729         if (indicatorp)
 730                 ccw_device_dma_free(vcdev->cdev, indicatorp,
 731                                     sizeof(indicators(vcdev)));
 732         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 733         virtio_ccw_del_vqs(vdev);
 734         return ret;
 735 }
 736
 737 static void virtio_ccw_reset(struct virtio_device *vdev)
 738 {
 739         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 740         struct ccw1 *ccw;
 741
 742         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 743         if (!ccw)
 744                 return;
 745
 746         /* Zero status bits. */
 747         vcdev->dma_area->status = 0;
 748
 749         /* Send a reset ccw on device. */
 750         ccw->cmd_code = CCW_CMD_VDEV_RESET;
 751         ccw->flags = 0;
 752         ccw->count = 0;
 753         ccw->cda = 0;
 754         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 755         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 756 }
 757
 758 static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 759 {
 760         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 761         struct virtio_feature_desc *features;
 762         int ret;
 763         u64 rc;
 764         struct ccw1 *ccw;
 765
 766         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 767         if (!ccw)
 768                 return 0;
 769
 770         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 771         if (!features) {
 772                 rc = 0;
 773                 goto out_free;
 774         }
 775         /* Read the feature bits from the host. */
 776         features->index = 0;
 777         ccw->cmd_code = CCW_CMD_READ_FEAT;
 778         ccw->flags = 0;
 779         ccw->count = sizeof(*features);
 780         ccw->cda = (__u32)virt_to_phys(features);
 781         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 782         if (ret) {
 783                 rc = 0;
 784                 goto out_free;
 785         }
 786
 787         rc = le32_to_cpu(features->features);
 788
 789         if (vcdev->revision == 0)
 790                 goto out_free;
 791
 792         /* Read second half of the feature bits from the host. */
 793         features->index = 1;
 794         ccw->cmd_code = CCW_CMD_READ_FEAT;
 795         ccw->flags = 0;
 796         ccw->count = sizeof(*features);
 797         ccw->cda = (__u32)virt_to_phys(features);
 798         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 799         if (ret == 0)
 800                 rc |= (u64)le32_to_cpu(features->features) << 32;
 801
 802 out_free:
 803         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 804         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 805         return rc;
 806 }
 807
 808 static void ccw_transport_features(struct virtio_device *vdev)
 809 {
 810         /*
 811          * Currently nothing to do here.
 812          */
 813 }
 814
 815 static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 816 {
 817         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 818         struct virtio_feature_desc *features;
 819         struct ccw1 *ccw;
 820         int ret;
 821
 822         if (vcdev->revision >= 1 &&
 823             !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 824                 dev_err(&vdev->dev, "virtio: device uses revision 1 "
 825                         "but does not have VIRTIO_F_VERSION_1\n");
 826                 return -EINVAL;
 827         }
 828
 829         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 830         if (!ccw)
 831                 return -ENOMEM;
 832
 833         features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 834         if (!features) {
 835                 ret = -ENOMEM;
 836                 goto out_free;
 837         }
 838         /* Give virtio_ring a chance to accept features. */
 839         vring_transport_features(vdev);
 840
 841         /* Give virtio_ccw a chance to accept features. */
 842         ccw_transport_features(vdev);
 843
 844         features->index = 0;
 845         features->features = cpu_to_le32((u32)vdev->features);
 846         /* Write the first half of the feature bits to the host. */
 847         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 848         ccw->flags = 0;
 849         ccw->count = sizeof(*features);
 850         ccw->cda = (__u32)virt_to_phys(features);
 851         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 852         if (ret)
 853                 goto out_free;
 854
 855         if (vcdev->revision == 0)
 856                 goto out_free;
 857
 858         features->index = 1;
 859         features->features = cpu_to_le32(vdev->features >> 32);
 860         /* Write the second half of the feature bits to the host. */
 861         ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 862         ccw->flags = 0;
 863         ccw->count = sizeof(*features);
 864         ccw->cda = (__u32)virt_to_phys(features);
 865         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 866
 867 out_free:
 868         ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 869         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 870
 871         return ret;
 872 }
 873
 874 static void virtio_ccw_get_config(struct virtio_device *vdev,
 875                                   unsigned int offset, void *buf, unsigned len)
 876 {
 877         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 878         int ret;
 879         struct ccw1 *ccw;
 880         void *config_area;
 881         unsigned long flags;
 882
 883         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 884         if (!ccw)
 885                 return;
 886
 887         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 888                                             VIRTIO_CCW_CONFIG_SIZE);
 889         if (!config_area)
 890                 goto out_free;
 891
 892         /* Read the config area from the host. */
 893         ccw->cmd_code = CCW_CMD_READ_CONF;
 894         ccw->flags = 0;
 895         ccw->count = offset + len;
 896         ccw->cda = (__u32)virt_to_phys(config_area);
 897         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 898         if (ret)
 899                 goto out_free;
 900
 901         spin_lock_irqsave(&vcdev->lock, flags);
 902         memcpy(vcdev->config, config_area, offset + len);
 903         if (vcdev->config_ready < offset + len)
 904                 vcdev->config_ready = offset + len;
 905         spin_unlock_irqrestore(&vcdev->lock, flags);
 906         if (buf)
 907                 memcpy(buf, config_area + offset, len);
 908
 909 out_free:
 910         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 911         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 912 }
 913
 914 static void virtio_ccw_set_config(struct virtio_device *vdev,
 915                                   unsigned int offset, const void *buf,
 916                                   unsigned len)
 917 {
 918         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 919         struct ccw1 *ccw;
 920         void *config_area;
 921         unsigned long flags;
 922
 923         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 924         if (!ccw)
 925                 return;
 926
 927         config_area = ccw_device_dma_zalloc(vcdev->cdev,
 928                                             VIRTIO_CCW_CONFIG_SIZE);
 929         if (!config_area)
 930                 goto out_free;
 931
 932         /* Make sure we don't overwrite fields. */
 933         if (vcdev->config_ready < offset)
 934                 virtio_ccw_get_config(vdev, 0, NULL, offset);
 935         spin_lock_irqsave(&vcdev->lock, flags);
 936         memcpy(&vcdev->config[offset], buf, len);
 937         /* Write the config area to the host. */
 938         memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 939         spin_unlock_irqrestore(&vcdev->lock, flags);
 940         ccw->cmd_code = CCW_CMD_WRITE_CONF;
 941         ccw->flags = 0;
 942         ccw->count = offset + len;
 943         ccw->cda = (__u32)virt_to_phys(config_area);
 944         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 945
 946 out_free:
 947         ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 948         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 949 }
 950
 951 static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 952 {
 953         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 954         u8 old_status = vcdev->dma_area->status;
 955         struct ccw1 *ccw;
 956
 957         if (vcdev->revision < 2)
 958                 return vcdev->dma_area->status;
 959
 960         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 961         if (!ccw)
 962                 return old_status;
 963
 964         ccw->cmd_code = CCW_CMD_READ_STATUS;
 965         ccw->flags = 0;
 966         ccw->count = sizeof(vcdev->dma_area->status);
 967         ccw->cda = (__u32)virt_to_phys(&vcdev->dma_area->status);
 968         ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 969 /*
 970  * If the channel program failed (should only happen if the device
 971  * was hotunplugged, and then we clean up via the machine check
 972  * handler anyway), vcdev->dma_area->status was not overwritten and we just
 973  * return the old status, which is fine.
 974 */
 975         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 976
 977         return vcdev->dma_area->status;
 978 }
 979
 980 static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 981 {
 982         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 983         u8 old_status = vcdev->dma_area->status;
 984         struct ccw1 *ccw;
 985         int ret;
 986
 987         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 988         if (!ccw)
 989                 return;
 990
 991         /* Write the status to the host. */
 992         vcdev->dma_area->status = status;
 993         ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 994         ccw->flags = 0;
 995         ccw->count = sizeof(status);
 996         ccw->cda = (__u32)virt_to_phys(&vcdev->dma_area->status);
 997         /* We use ssch for setting the status which is a serializing
 998          * instruction that guarantees the memory writes have
 999          * completed before ssch.
1000          */
1001         ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
1002         /* Write failed? We assume status is unchanged. */
1003         if (ret)
1004                 vcdev->dma_area->status = old_status;
1005         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1006 }
1007
1008 static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
1009 {
1010         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1011
1012         return dev_name(&vcdev->cdev->dev);
1013 }
1014
1015 static void virtio_ccw_synchronize_cbs(struct virtio_device *vdev)
1016 {
1017         struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1018         struct airq_info *info = vcdev->airq_info;
1019
1020         if (info) {
1021                 /*
1022                  * This device uses adapter interrupts: synchronize with
1023                  * vring_interrupt() called by virtio_airq_handler()
1024                  * via the indicator area lock.
1025                  */
1026                 write_lock_irq(&info->lock);
1027                 write_unlock_irq(&info->lock);
1028         } else {
1029                 /* This device uses classic interrupts: synchronize
1030                  * with vring_interrupt() called by
1031                  * virtio_ccw_int_handler() via the per-device
1032                  * irq_lock
1033                  */
1034                 write_lock_irq(&vcdev->irq_lock);
1035                 write_unlock_irq(&vcdev->irq_lock);
1036         }
1037 }
1038
1039 static const struct virtio_config_ops virtio_ccw_config_ops = {
1040         .get_features = virtio_ccw_get_features,
1041         .finalize_features = virtio_ccw_finalize_features,
1042         .get = virtio_ccw_get_config,
1043         .set = virtio_ccw_set_config,
1044         .get_status = virtio_ccw_get_status,
1045         .set_status = virtio_ccw_set_status,
1046         .reset = virtio_ccw_reset,
1047         .find_vqs = virtio_ccw_find_vqs,
1048         .del_vqs = virtio_ccw_del_vqs,
1049         .bus_name = virtio_ccw_bus_name,
1050         .synchronize_cbs = virtio_ccw_synchronize_cbs,
1051 };
1052
1053
1054 /*
1055  * ccw bus driver related functions
1056  */
1057
1058 static void virtio_ccw_release_dev(struct device *_d)
1059 {
1060         struct virtio_device *dev = dev_to_virtio(_d);
1061         struct virtio_ccw_device *vcdev = to_vc_device(dev);
1062
1063         ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1064                             sizeof(*vcdev->dma_area));
1065         kfree(vcdev);
1066 }
1067
1068 static int irb_is_error(struct irb *irb)
1069 {
1070         if (scsw_cstat(&irb->scsw) != 0)
1071                 return 1;
1072         if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1073                 return 1;
1074         if (scsw_cc(&irb->scsw) != 0)
1075                 return 1;
1076         return 0;
1077 }
1078
1079 static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1080                                               int index)
1081 {
1082         struct virtio_ccw_vq_info *info;
1083         unsigned long flags;
1084         struct virtqueue *vq;
1085
1086         vq = NULL;
1087         spin_lock_irqsave(&vcdev->lock, flags);
1088         list_for_each_entry(info, &vcdev->virtqueues, node) {
1089                 if (info->vq->index == index) {
1090                         vq = info->vq;
1091                         break;
1092                 }
1093         }
1094         spin_unlock_irqrestore(&vcdev->lock, flags);
1095         return vq;
1096 }
1097
1098 static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1099                                       __u32 activity)
1100 {
1101         if (vcdev->curr_io & activity) {
1102                 switch (activity) {
1103                 case VIRTIO_CCW_DOING_READ_FEAT:
1104                 case VIRTIO_CCW_DOING_WRITE_FEAT:
1105                 case VIRTIO_CCW_DOING_READ_CONFIG:
1106                 case VIRTIO_CCW_DOING_WRITE_CONFIG:
1107                 case VIRTIO_CCW_DOING_WRITE_STATUS:
1108                 case VIRTIO_CCW_DOING_READ_STATUS:
1109                 case VIRTIO_CCW_DOING_SET_VQ:
1110                 case VIRTIO_CCW_DOING_SET_IND:
1111                 case VIRTIO_CCW_DOING_SET_CONF_IND:
1112                 case VIRTIO_CCW_DOING_RESET:
1113                 case VIRTIO_CCW_DOING_READ_VQ_CONF:
1114                 case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1115                 case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1116                         vcdev->curr_io &= ~activity;
1117                         wake_up(&vcdev->wait_q);
1118                         break;
1119                 default:
1120                         /* don't know what to do... */
1121                         dev_warn(&vcdev->cdev->dev,
1122                                  "Suspicious activity '%08x'\n", activity);
1123                         WARN_ON(1);
1124                         break;
1125                 }
1126         }
1127 }
1128
1129 static void virtio_ccw_int_handler(struct ccw_device *cdev,
1130                                    unsigned long intparm,
1131                                    struct irb *irb)
1132 {
1133         __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1134         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1135         int i;
1136         struct virtqueue *vq;
1137
1138         if (!vcdev)
1139                 return;
1140         if (IS_ERR(irb)) {
1141                 vcdev->err = PTR_ERR(irb);
1142                 virtio_ccw_check_activity(vcdev, activity);
1143                 /* Don't poke around indicators, something's wrong. */
1144                 return;
1145         }
1146         /* Check if it's a notification from the host. */
1147         if ((intparm == 0) &&
1148             (scsw_stctl(&irb->scsw) ==
1149              (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1150                 /* OK */
1151         }
1152         if (irb_is_error(irb)) {
1153                 /* Command reject? */
1154                 if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1155                     (irb->ecw[0] & SNS0_CMD_REJECT))
1156                         vcdev->err = -EOPNOTSUPP;
1157                 else
1158                         /* Map everything else to -EIO. */
1159                         vcdev->err = -EIO;
1160         }
1161         virtio_ccw_check_activity(vcdev, activity);
1162 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1163         /*
1164          * Paired with virtio_ccw_synchronize_cbs() and interrupts are
1165          * disabled here.
1166          */
1167         read_lock(&vcdev->irq_lock);
1168 #endif
1169         for_each_set_bit(i, indicators(vcdev),
1170                          sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1171                 /* The bit clear must happen before the vring kick. */
1172                 clear_bit(i, indicators(vcdev));
1173                 barrier();
1174                 vq = virtio_ccw_vq_by_ind(vcdev, i);
1175                 vring_interrupt(0, vq);
1176         }
1177 #ifdef CONFIG_VIRTIO_HARDEN_NOTIFICATION
1178         read_unlock(&vcdev->irq_lock);
1179 #endif
1180         if (test_bit(0, indicators2(vcdev))) {
1181                 virtio_config_changed(&vcdev->vdev);
1182                 clear_bit(0, indicators2(vcdev));
1183         }
1184 }
1185
1186 /*
1187  * We usually want to autoonline all devices, but give the admin
1188  * a way to exempt devices from this.
1189  */
1190 #define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1191                      (8*sizeof(long)))
1192 static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1193
1194 static char *no_auto = "";
1195
1196 module_param(no_auto, charp, 0444);
1197 MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1198
1199 static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1200 {
1201         struct ccw_dev_id id;
1202
1203         ccw_device_get_id(cdev, &id);
1204         if (test_bit(id.devno, devs_no_auto[id.ssid]))
1205                 return 0;
1206         return 1;
1207 }
1208
1209 static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1210 {
1211         struct ccw_device *cdev = data;
1212         int ret;
1213
1214         ret = ccw_device_set_online(cdev);
1215         if (ret)
1216                 dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1217 }
1218
1219 static int virtio_ccw_probe(struct ccw_device *cdev)
1220 {
1221         cdev->handler = virtio_ccw_int_handler;
1222
1223         if (virtio_ccw_check_autoonline(cdev))
1224                 async_schedule(virtio_ccw_auto_online, cdev);
1225         return 0;
1226 }
1227
1228 static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1229 {
1230         unsigned long flags;
1231         struct virtio_ccw_device *vcdev;
1232
1233         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1234         vcdev = dev_get_drvdata(&cdev->dev);
1235         if (!vcdev || vcdev->going_away) {
1236                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1237                 return NULL;
1238         }
1239         vcdev->going_away = true;
1240         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1241         return vcdev;
1242 }
1243
1244 static void virtio_ccw_remove(struct ccw_device *cdev)
1245 {
1246         unsigned long flags;
1247         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1248
1249         if (vcdev && cdev->online) {
1250                 if (vcdev->device_lost)
1251                         virtio_break_device(&vcdev->vdev);
1252                 unregister_virtio_device(&vcdev->vdev);
1253                 spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1254                 dev_set_drvdata(&cdev->dev, NULL);
1255                 spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1256         }
1257         cdev->handler = NULL;
1258 }
1259
1260 static int virtio_ccw_offline(struct ccw_device *cdev)
1261 {
1262         unsigned long flags;
1263         struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1264
1265         if (!vcdev)
1266                 return 0;
1267         if (vcdev->device_lost)
1268                 virtio_break_device(&vcdev->vdev);
1269         unregister_virtio_device(&vcdev->vdev);
1270         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1271         dev_set_drvdata(&cdev->dev, NULL);
1272         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1273         return 0;
1274 }
1275
1276 static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1277 {
1278         struct virtio_rev_info *rev;
1279         struct ccw1 *ccw;
1280         int ret;
1281
1282         ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1283         if (!ccw)
1284                 return -ENOMEM;
1285         rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1286         if (!rev) {
1287                 ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1288                 return -ENOMEM;
1289         }
1290
1291         /* Set transport revision */
1292         ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1293         ccw->flags = 0;
1294         ccw->count = sizeof(*rev);
1295         ccw->cda = (__u32)virt_to_phys(rev);
1296
1297         vcdev->revision = VIRTIO_CCW_REV_MAX;
1298         do {
1299                 rev->revision = vcdev->revision;
1300                 /* none of our supported revisions carry payload */
1301                 rev->length = 0;
1302                 ret = ccw_io_helper(vcdev, ccw,
1303                                     VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1304                 if (ret == -EOPNOTSUPP) {
1305                         if (vcdev->revision == 0)
1306                                 /*
1307                                  * The host device does not support setting
1308                                  * the revision: let's operate it in legacy
1309                                  * mode.
1310                                  */
1311                                 ret = 0;
1312                         else
1313                                 vcdev->revision--;
1314                 }
1315         } while (ret == -EOPNOTSUPP);
1316
1317         ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1318         ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1319         return ret;
1320 }
1321
1322 static int virtio_ccw_online(struct ccw_device *cdev)
1323 {
1324         int ret;
1325         struct virtio_ccw_device *vcdev;
1326         unsigned long flags;
1327
1328         vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1329         if (!vcdev) {
1330                 dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1331                 ret = -ENOMEM;
1332                 goto out_free;
1333         }
1334         vcdev->vdev.dev.parent = &cdev->dev;
1335         vcdev->cdev = cdev;
1336         vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1337                                                 sizeof(*vcdev->dma_area));
1338         if (!vcdev->dma_area) {
1339                 ret = -ENOMEM;
1340                 goto out_free;
1341         }
1342
1343         vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1344
1345         vcdev->vdev.dev.release = virtio_ccw_release_dev;
1346         vcdev->vdev.config = &virtio_ccw_config_ops;
1347         init_waitqueue_head(&vcdev->wait_q);
1348         INIT_LIST_HEAD(&vcdev->virtqueues);
1349         spin_lock_init(&vcdev->lock);
1350         rwlock_init(&vcdev->irq_lock);
1351         mutex_init(&vcdev->io_lock);
1352
1353         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1354         dev_set_drvdata(&cdev->dev, vcdev);
1355         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1356         vcdev->vdev.id.vendor = cdev->id.cu_type;
1357         vcdev->vdev.id.device = cdev->id.cu_model;
1358
1359         ret = virtio_ccw_set_transport_rev(vcdev);
1360         if (ret)
1361                 goto out_free;
1362
1363         ret = register_virtio_device(&vcdev->vdev);
1364         if (ret) {
1365                 dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1366                          ret);
1367                 goto out_put;
1368         }
1369         return 0;
1370 out_put:
1371         spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1372         dev_set_drvdata(&cdev->dev, NULL);
1373         spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1374         put_device(&vcdev->vdev.dev);
1375         return ret;
1376 out_free:
1377         if (vcdev) {
1378                 ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1379                                     sizeof(*vcdev->dma_area));
1380         }
1381         kfree(vcdev);
1382         return ret;
1383 }
1384
1385 static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1386 {
1387         int rc;
1388         struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1389
1390         /*
1391          * Make sure vcdev is set
1392          * i.e. set_offline/remove callback not already running
1393          */
1394         if (!vcdev)
1395                 return NOTIFY_DONE;
1396
1397         switch (event) {
1398         case CIO_GONE:
1399                 vcdev->device_lost = true;
1400                 rc = NOTIFY_DONE;
1401                 break;
1402         case CIO_OPER:
1403                 rc = NOTIFY_OK;
1404                 break;
1405         default:
1406                 rc = NOTIFY_DONE;
1407                 break;
1408         }
1409         return rc;
1410 }
1411
1412 static struct ccw_device_id virtio_ids[] = {
1413         { CCW_DEVICE(0x3832, 0) },
1414         {},
1415 };
1416
1417 static struct ccw_driver virtio_ccw_driver = {
1418         .driver = {
1419                 .owner = THIS_MODULE,
1420                 .name = "virtio_ccw",
1421         },
1422         .ids = virtio_ids,
1423         .probe = virtio_ccw_probe,
1424         .remove = virtio_ccw_remove,
1425         .set_offline = virtio_ccw_offline,
1426         .set_online = virtio_ccw_online,
1427         .notify = virtio_ccw_cio_notify,
1428         .int_class = IRQIO_VIR,
1429 };
1430
1431 static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1432                            int max_digit, int max_val)
1433 {
1434         int diff;
1435
1436         diff = 0;
1437         *val = 0;
1438
1439         while (diff <= max_digit) {
1440                 int value = hex_to_bin(**cp);
1441
1442                 if (value < 0)
1443                         break;
1444                 *val = *val * 16 + value;
1445                 (*cp)++;
1446                 diff++;
1447         }
1448
1449         if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1450                 return 1;
1451
1452         return 0;
1453 }
1454
1455 static int __init parse_busid(char *str, unsigned int *cssid,
1456                               unsigned int *ssid, unsigned int *devno)
1457 {
1458         char *str_work;
1459         int rc, ret;
1460
1461         rc = 1;
1462
1463         if (*str == '\0')
1464                 goto out;
1465
1466         str_work = str;
1467         ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1468         if (ret || (str_work[0] != '.'))
1469                 goto out;
1470         str_work++;
1471         ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1472         if (ret || (str_work[0] != '.'))
1473                 goto out;
1474         str_work++;
1475         ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1476         if (ret || (str_work[0] != '\0'))
1477                 goto out;
1478
1479         rc = 0;
1480 out:
1481         return rc;
1482 }
1483
1484 static void __init no_auto_parse(void)
1485 {
1486         unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1487         char *parm, *str;
1488         int rc;
1489
1490         str = no_auto;
1491         while ((parm = strsep(&str, ","))) {
1492                 rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1493                                  &from_ssid, &from);
1494                 if (rc)
1495                         continue;
1496                 if (parm != NULL) {
1497                         rc = parse_busid(parm, &to_cssid,
1498                                          &to_ssid, &to);
1499                         if ((from_ssid > to_ssid) ||
1500                             ((from_ssid == to_ssid) && (from > to)))
1501                                 rc = -EINVAL;
1502                 } else {
1503                         to_cssid = from_cssid;
1504                         to_ssid = from_ssid;
1505                         to = from;
1506                 }
1507                 if (rc)
1508                         continue;
1509                 while ((from_ssid < to_ssid) ||
1510                        ((from_ssid == to_ssid) && (from <= to))) {
1511                         set_bit(from, devs_no_auto[from_ssid]);
1512                         from++;
1513                         if (from > __MAX_SUBCHANNEL) {
1514                                 from_ssid++;
1515                                 from = 0;
1516                         }
1517                 }
1518         }
1519 }
1520
1521 static int __init virtio_ccw_init(void)
1522 {
1523         int rc;
1524
1525         /* parse no_auto string before we do anything further */
1526         no_auto_parse();
1527
1528         summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1529         if (!summary_indicators)
1530                 return -ENOMEM;
1531         rc = ccw_driver_register(&virtio_ccw_driver);
1532         if (rc)
1533                 cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1534         return rc;
1535 }
1536 device_initcall(virtio_ccw_init);