linux/drivers/s390/virtio/virtio_ccw.c
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   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
  41struct 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
  49struct vcdev_dma_area {
  50        unsigned long indicators;
  51        unsigned long indicators2;
  52        struct vq_config_block config_block;
  53        __u8 status;
  54};
  55
  56struct 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
  75static inline unsigned long *indicators(struct virtio_ccw_device *vcdev)
  76{
  77        return &vcdev->dma_area->indicators;
  78}
  79
  80static inline unsigned long *indicators2(struct virtio_ccw_device *vcdev)
  81{
  82        return &vcdev->dma_area->indicators2;
  83}
  84
  85struct vq_info_block_legacy {
  86        __u64 queue;
  87        __u32 align;
  88        __u16 index;
  89        __u16 num;
  90} __packed;
  91
  92struct vq_info_block {
  93        __u64 desc;
  94        __u32 res0;
  95        __u16 index;
  96        __u16 num;
  97        __u64 avail;
  98        __u64 used;
  99} __packed;
 100
 101struct virtio_feature_desc {
 102        __le32 features;
 103        __u8 index;
 104} __packed;
 105
 106struct virtio_thinint_area {
 107        unsigned long summary_indicator;
 108        unsigned long indicator;
 109        u64 bit_nr;
 110        u8 isc;
 111} __packed;
 112
 113struct 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 2
 121
 122struct 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
 139static int virtio_ccw_use_airq = 1;
 140
 141struct airq_info {
 142        rwlock_t lock;
 143        u8 summary_indicator_idx;
 144        struct airq_struct airq;
 145        struct airq_iv *aiv;
 146};
 147static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
 148static DEFINE_MUTEX(airq_areas_lock);
 149
 150static u8 *summary_indicators;
 151
 152static inline u8 *get_summary_indicator(struct airq_info *info)
 153{
 154        return summary_indicators + info->summary_indicator_idx;
 155}
 156
 157#define CCW_CMD_SET_VQ 0x13
 158#define CCW_CMD_VDEV_RESET 0x33
 159#define CCW_CMD_SET_IND 0x43
 160#define CCW_CMD_SET_CONF_IND 0x53
 161#define CCW_CMD_READ_FEAT 0x12
 162#define CCW_CMD_WRITE_FEAT 0x11
 163#define CCW_CMD_READ_CONF 0x22
 164#define CCW_CMD_WRITE_CONF 0x21
 165#define CCW_CMD_WRITE_STATUS 0x31
 166#define CCW_CMD_READ_VQ_CONF 0x32
 167#define CCW_CMD_READ_STATUS 0x72
 168#define CCW_CMD_SET_IND_ADAPTER 0x73
 169#define CCW_CMD_SET_VIRTIO_REV 0x83
 170
 171#define VIRTIO_CCW_DOING_SET_VQ 0x00010000
 172#define VIRTIO_CCW_DOING_RESET 0x00040000
 173#define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
 174#define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
 175#define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
 176#define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
 177#define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
 178#define VIRTIO_CCW_DOING_SET_IND 0x01000000
 179#define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
 180#define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
 181#define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
 182#define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
 183#define VIRTIO_CCW_DOING_READ_STATUS 0x20000000
 184#define VIRTIO_CCW_INTPARM_MASK 0xffff0000
 185
 186static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
 187{
 188        return container_of(vdev, struct virtio_ccw_device, vdev);
 189}
 190
 191static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
 192{
 193        unsigned long i, flags;
 194
 195        write_lock_irqsave(&info->lock, flags);
 196        for (i = 0; i < airq_iv_end(info->aiv); i++) {
 197                if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
 198                        airq_iv_free_bit(info->aiv, i);
 199                        airq_iv_set_ptr(info->aiv, i, 0);
 200                        break;
 201                }
 202        }
 203        write_unlock_irqrestore(&info->lock, flags);
 204}
 205
 206static void virtio_airq_handler(struct airq_struct *airq, bool floating)
 207{
 208        struct airq_info *info = container_of(airq, struct airq_info, airq);
 209        unsigned long ai;
 210
 211        inc_irq_stat(IRQIO_VAI);
 212        read_lock(&info->lock);
 213        /* Walk through indicators field, summary indicator active. */
 214        for (ai = 0;;) {
 215                ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 216                if (ai == -1UL)
 217                        break;
 218                vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 219        }
 220        *(get_summary_indicator(info)) = 0;
 221        smp_wmb();
 222        /* Walk through indicators field, summary indicator not active. */
 223        for (ai = 0;;) {
 224                ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
 225                if (ai == -1UL)
 226                        break;
 227                vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
 228        }
 229        read_unlock(&info->lock);
 230}
 231
 232static struct airq_info *new_airq_info(int index)
 233{
 234        struct airq_info *info;
 235        int rc;
 236
 237        info = kzalloc(sizeof(*info), GFP_KERNEL);
 238        if (!info)
 239                return NULL;
 240        rwlock_init(&info->lock);
 241        info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR
 242                                   | AIRQ_IV_CACHELINE);
 243        if (!info->aiv) {
 244                kfree(info);
 245                return NULL;
 246        }
 247        info->airq.handler = virtio_airq_handler;
 248        info->summary_indicator_idx = index;
 249        info->airq.lsi_ptr = get_summary_indicator(info);
 250        info->airq.lsi_mask = 0xff;
 251        info->airq.isc = VIRTIO_AIRQ_ISC;
 252        rc = register_adapter_interrupt(&info->airq);
 253        if (rc) {
 254                airq_iv_release(info->aiv);
 255                kfree(info);
 256                return NULL;
 257        }
 258        return info;
 259}
 260
 261static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
 262                                        u64 *first, void **airq_info)
 263{
 264        int i, j;
 265        struct airq_info *info;
 266        unsigned long indicator_addr = 0;
 267        unsigned long bit, flags;
 268
 269        for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
 270                mutex_lock(&airq_areas_lock);
 271                if (!airq_areas[i])
 272                        airq_areas[i] = new_airq_info(i);
 273                info = airq_areas[i];
 274                mutex_unlock(&airq_areas_lock);
 275                if (!info)
 276                        return 0;
 277                write_lock_irqsave(&info->lock, flags);
 278                bit = airq_iv_alloc(info->aiv, nvqs);
 279                if (bit == -1UL) {
 280                        /* Not enough vacancies. */
 281                        write_unlock_irqrestore(&info->lock, flags);
 282                        continue;
 283                }
 284                *first = bit;
 285                *airq_info = info;
 286                indicator_addr = (unsigned long)info->aiv->vector;
 287                for (j = 0; j < nvqs; j++) {
 288                        airq_iv_set_ptr(info->aiv, bit + j,
 289                                        (unsigned long)vqs[j]);
 290                }
 291                write_unlock_irqrestore(&info->lock, flags);
 292        }
 293        return indicator_addr;
 294}
 295
 296static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
 297{
 298        struct virtio_ccw_vq_info *info;
 299
 300        if (!vcdev->airq_info)
 301                return;
 302        list_for_each_entry(info, &vcdev->virtqueues, node)
 303                drop_airq_indicator(info->vq, vcdev->airq_info);
 304}
 305
 306static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
 307{
 308        unsigned long flags;
 309        __u32 ret;
 310
 311        spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 312        if (vcdev->err)
 313                ret = 0;
 314        else
 315                ret = vcdev->curr_io & flag;
 316        spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 317        return ret;
 318}
 319
 320static int ccw_io_helper(struct virtio_ccw_device *vcdev,
 321                         struct ccw1 *ccw, __u32 intparm)
 322{
 323        int ret;
 324        unsigned long flags;
 325        int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
 326
 327        mutex_lock(&vcdev->io_lock);
 328        do {
 329                spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
 330                ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
 331                if (!ret) {
 332                        if (!vcdev->curr_io)
 333                                vcdev->err = 0;
 334                        vcdev->curr_io |= flag;
 335                }
 336                spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
 337                cpu_relax();
 338        } while (ret == -EBUSY);
 339        wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
 340        ret = ret ? ret : vcdev->err;
 341        mutex_unlock(&vcdev->io_lock);
 342        return ret;
 343}
 344
 345static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
 346                                      struct ccw1 *ccw)
 347{
 348        int ret;
 349        unsigned long *indicatorp = NULL;
 350        struct virtio_thinint_area *thinint_area = NULL;
 351        struct airq_info *airq_info = vcdev->airq_info;
 352
 353        if (vcdev->is_thinint) {
 354                thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 355                                                     sizeof(*thinint_area));
 356                if (!thinint_area)
 357                        return;
 358                thinint_area->summary_indicator =
 359                        (unsigned long) get_summary_indicator(airq_info);
 360                thinint_area->isc = VIRTIO_AIRQ_ISC;
 361                ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 362                ccw->count = sizeof(*thinint_area);
 363                ccw->cda = (__u32)(unsigned long) thinint_area;
 364        } else {
 365                /* payload is the address of the indicators */
 366                indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 367                                                   sizeof(indicators(vcdev)));
 368                if (!indicatorp)
 369                        return;
 370                *indicatorp = 0;
 371                ccw->cmd_code = CCW_CMD_SET_IND;
 372                ccw->count = sizeof(indicators(vcdev));
 373                ccw->cda = (__u32)(unsigned long) indicatorp;
 374        }
 375        /* Deregister indicators from host. */
 376        *indicators(vcdev) = 0;
 377        ccw->flags = 0;
 378        ret = ccw_io_helper(vcdev, ccw,
 379                            vcdev->is_thinint ?
 380                            VIRTIO_CCW_DOING_SET_IND_ADAPTER :
 381                            VIRTIO_CCW_DOING_SET_IND);
 382        if (ret && (ret != -ENODEV))
 383                dev_info(&vcdev->cdev->dev,
 384                         "Failed to deregister indicators (%d)\n", ret);
 385        else if (vcdev->is_thinint)
 386                virtio_ccw_drop_indicators(vcdev);
 387        ccw_device_dma_free(vcdev->cdev, indicatorp, sizeof(indicators(vcdev)));
 388        ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 389}
 390
 391static inline long __do_kvm_notify(struct subchannel_id schid,
 392                                   unsigned long queue_index,
 393                                   long cookie)
 394{
 395        register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
 396        register struct subchannel_id __schid asm("2") = schid;
 397        register unsigned long __index asm("3") = queue_index;
 398        register long __rc asm("2");
 399        register long __cookie asm("4") = cookie;
 400
 401        asm volatile ("diag 2,4,0x500\n"
 402                      : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
 403                      "d"(__cookie)
 404                      : "memory", "cc");
 405        return __rc;
 406}
 407
 408static inline long do_kvm_notify(struct subchannel_id schid,
 409                                 unsigned long queue_index,
 410                                 long cookie)
 411{
 412        diag_stat_inc(DIAG_STAT_X500);
 413        return __do_kvm_notify(schid, queue_index, cookie);
 414}
 415
 416static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
 417{
 418        struct virtio_ccw_vq_info *info = vq->priv;
 419        struct virtio_ccw_device *vcdev;
 420        struct subchannel_id schid;
 421
 422        vcdev = to_vc_device(info->vq->vdev);
 423        ccw_device_get_schid(vcdev->cdev, &schid);
 424        info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
 425        if (info->cookie < 0)
 426                return false;
 427        return true;
 428}
 429
 430static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
 431                                   struct ccw1 *ccw, int index)
 432{
 433        int ret;
 434
 435        vcdev->dma_area->config_block.index = index;
 436        ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
 437        ccw->flags = 0;
 438        ccw->count = sizeof(struct vq_config_block);
 439        ccw->cda = (__u32)(unsigned long)(&vcdev->dma_area->config_block);
 440        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
 441        if (ret)
 442                return ret;
 443        return vcdev->dma_area->config_block.num ?: -ENOENT;
 444}
 445
 446static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
 447{
 448        struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
 449        struct virtio_ccw_vq_info *info = vq->priv;
 450        unsigned long flags;
 451        int ret;
 452        unsigned int index = vq->index;
 453
 454        /* Remove from our list. */
 455        spin_lock_irqsave(&vcdev->lock, flags);
 456        list_del(&info->node);
 457        spin_unlock_irqrestore(&vcdev->lock, flags);
 458
 459        /* Release from host. */
 460        if (vcdev->revision == 0) {
 461                info->info_block->l.queue = 0;
 462                info->info_block->l.align = 0;
 463                info->info_block->l.index = index;
 464                info->info_block->l.num = 0;
 465                ccw->count = sizeof(info->info_block->l);
 466        } else {
 467                info->info_block->s.desc = 0;
 468                info->info_block->s.index = index;
 469                info->info_block->s.num = 0;
 470                info->info_block->s.avail = 0;
 471                info->info_block->s.used = 0;
 472                ccw->count = sizeof(info->info_block->s);
 473        }
 474        ccw->cmd_code = CCW_CMD_SET_VQ;
 475        ccw->flags = 0;
 476        ccw->cda = (__u32)(unsigned long)(info->info_block);
 477        ret = ccw_io_helper(vcdev, ccw,
 478                            VIRTIO_CCW_DOING_SET_VQ | index);
 479        /*
 480         * -ENODEV isn't considered an error: The device is gone anyway.
 481         * This may happen on device detach.
 482         */
 483        if (ret && (ret != -ENODEV))
 484                dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d\n",
 485                         ret, index);
 486
 487        vring_del_virtqueue(vq);
 488        ccw_device_dma_free(vcdev->cdev, info->info_block,
 489                            sizeof(*info->info_block));
 490        kfree(info);
 491}
 492
 493static void virtio_ccw_del_vqs(struct virtio_device *vdev)
 494{
 495        struct virtqueue *vq, *n;
 496        struct ccw1 *ccw;
 497        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 498
 499        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 500        if (!ccw)
 501                return;
 502
 503        virtio_ccw_drop_indicator(vcdev, ccw);
 504
 505        list_for_each_entry_safe(vq, n, &vdev->vqs, list)
 506                virtio_ccw_del_vq(vq, ccw);
 507
 508        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 509}
 510
 511static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
 512                                             int i, vq_callback_t *callback,
 513                                             const char *name, bool ctx,
 514                                             struct ccw1 *ccw)
 515{
 516        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 517        int err;
 518        struct virtqueue *vq = NULL;
 519        struct virtio_ccw_vq_info *info;
 520        u64 queue;
 521        unsigned long flags;
 522        bool may_reduce;
 523
 524        /* Allocate queue. */
 525        info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
 526        if (!info) {
 527                dev_warn(&vcdev->cdev->dev, "no info\n");
 528                err = -ENOMEM;
 529                goto out_err;
 530        }
 531        info->info_block = ccw_device_dma_zalloc(vcdev->cdev,
 532                                                 sizeof(*info->info_block));
 533        if (!info->info_block) {
 534                dev_warn(&vcdev->cdev->dev, "no info block\n");
 535                err = -ENOMEM;
 536                goto out_err;
 537        }
 538        info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
 539        if (info->num < 0) {
 540                err = info->num;
 541                goto out_err;
 542        }
 543        may_reduce = vcdev->revision > 0;
 544        vq = vring_create_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN,
 545                                    vdev, true, may_reduce, ctx,
 546                                    virtio_ccw_kvm_notify, callback, name);
 547
 548        if (!vq) {
 549                /* For now, we fail if we can't get the requested size. */
 550                dev_warn(&vcdev->cdev->dev, "no vq\n");
 551                err = -ENOMEM;
 552                goto out_err;
 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)(unsigned long)(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
 592out_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
 603static 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        struct airq_info *info;
 610
 611        thinint_area = ccw_device_dma_zalloc(vcdev->cdev,
 612                                             sizeof(*thinint_area));
 613        if (!thinint_area) {
 614                ret = -ENOMEM;
 615                goto out;
 616        }
 617        /* Try to get an indicator. */
 618        thinint_area->indicator = get_airq_indicator(vqs, nvqs,
 619                                                     &thinint_area->bit_nr,
 620                                                     &vcdev->airq_info);
 621        if (!thinint_area->indicator) {
 622                ret = -ENOSPC;
 623                goto out;
 624        }
 625        info = vcdev->airq_info;
 626        thinint_area->summary_indicator =
 627                (unsigned long) get_summary_indicator(info);
 628        thinint_area->isc = VIRTIO_AIRQ_ISC;
 629        ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
 630        ccw->flags = CCW_FLAG_SLI;
 631        ccw->count = sizeof(*thinint_area);
 632        ccw->cda = (__u32)(unsigned long)thinint_area;
 633        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
 634        if (ret) {
 635                if (ret == -EOPNOTSUPP) {
 636                        /*
 637                         * The host does not support adapter interrupts
 638                         * for virtio-ccw, stop trying.
 639                         */
 640                        virtio_ccw_use_airq = 0;
 641                        pr_info("Adapter interrupts unsupported on host\n");
 642                } else
 643                        dev_warn(&vcdev->cdev->dev,
 644                                 "enabling adapter interrupts = %d\n", ret);
 645                virtio_ccw_drop_indicators(vcdev);
 646        }
 647out:
 648        ccw_device_dma_free(vcdev->cdev, thinint_area, sizeof(*thinint_area));
 649        return ret;
 650}
 651
 652static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
 653                               struct virtqueue *vqs[],
 654                               vq_callback_t *callbacks[],
 655                               const char * const names[],
 656                               const bool *ctx,
 657                               struct irq_affinity *desc)
 658{
 659        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 660        unsigned long *indicatorp = NULL;
 661        int ret, i, queue_idx = 0;
 662        struct ccw1 *ccw;
 663
 664        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 665        if (!ccw)
 666                return -ENOMEM;
 667
 668        for (i = 0; i < nvqs; ++i) {
 669                if (!names[i]) {
 670                        vqs[i] = NULL;
 671                        continue;
 672                }
 673
 674                vqs[i] = virtio_ccw_setup_vq(vdev, queue_idx++, callbacks[i],
 675                                             names[i], ctx ? ctx[i] : false,
 676                                             ccw);
 677                if (IS_ERR(vqs[i])) {
 678                        ret = PTR_ERR(vqs[i]);
 679                        vqs[i] = NULL;
 680                        goto out;
 681                }
 682        }
 683        ret = -ENOMEM;
 684        /*
 685         * We need a data area under 2G to communicate. Our payload is
 686         * the address of the indicators.
 687        */
 688        indicatorp = ccw_device_dma_zalloc(vcdev->cdev,
 689                                           sizeof(indicators(vcdev)));
 690        if (!indicatorp)
 691                goto out;
 692        *indicatorp = (unsigned long) indicators(vcdev);
 693        if (vcdev->is_thinint) {
 694                ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
 695                if (ret)
 696                        /* no error, just fall back to legacy interrupts */
 697                        vcdev->is_thinint = false;
 698        }
 699        if (!vcdev->is_thinint) {
 700                /* Register queue indicators with host. */
 701                *indicators(vcdev) = 0;
 702                ccw->cmd_code = CCW_CMD_SET_IND;
 703                ccw->flags = 0;
 704                ccw->count = sizeof(indicators(vcdev));
 705                ccw->cda = (__u32)(unsigned long) indicatorp;
 706                ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
 707                if (ret)
 708                        goto out;
 709        }
 710        /* Register indicators2 with host for config changes */
 711        *indicatorp = (unsigned long) indicators2(vcdev);
 712        *indicators2(vcdev) = 0;
 713        ccw->cmd_code = CCW_CMD_SET_CONF_IND;
 714        ccw->flags = 0;
 715        ccw->count = sizeof(indicators2(vcdev));
 716        ccw->cda = (__u32)(unsigned long) indicatorp;
 717        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
 718        if (ret)
 719                goto out;
 720
 721        if (indicatorp)
 722                ccw_device_dma_free(vcdev->cdev, indicatorp,
 723                                    sizeof(indicators(vcdev)));
 724        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 725        return 0;
 726out:
 727        if (indicatorp)
 728                ccw_device_dma_free(vcdev->cdev, indicatorp,
 729                                    sizeof(indicators(vcdev)));
 730        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 731        virtio_ccw_del_vqs(vdev);
 732        return ret;
 733}
 734
 735static void virtio_ccw_reset(struct virtio_device *vdev)
 736{
 737        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 738        struct ccw1 *ccw;
 739
 740        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 741        if (!ccw)
 742                return;
 743
 744        /* Zero status bits. */
 745        vcdev->dma_area->status = 0;
 746
 747        /* Send a reset ccw on device. */
 748        ccw->cmd_code = CCW_CMD_VDEV_RESET;
 749        ccw->flags = 0;
 750        ccw->count = 0;
 751        ccw->cda = 0;
 752        ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
 753        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 754}
 755
 756static u64 virtio_ccw_get_features(struct virtio_device *vdev)
 757{
 758        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 759        struct virtio_feature_desc *features;
 760        int ret;
 761        u64 rc;
 762        struct ccw1 *ccw;
 763
 764        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 765        if (!ccw)
 766                return 0;
 767
 768        features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 769        if (!features) {
 770                rc = 0;
 771                goto out_free;
 772        }
 773        /* Read the feature bits from the host. */
 774        features->index = 0;
 775        ccw->cmd_code = CCW_CMD_READ_FEAT;
 776        ccw->flags = 0;
 777        ccw->count = sizeof(*features);
 778        ccw->cda = (__u32)(unsigned long)features;
 779        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 780        if (ret) {
 781                rc = 0;
 782                goto out_free;
 783        }
 784
 785        rc = le32_to_cpu(features->features);
 786
 787        if (vcdev->revision == 0)
 788                goto out_free;
 789
 790        /* Read second half of the feature bits from the host. */
 791        features->index = 1;
 792        ccw->cmd_code = CCW_CMD_READ_FEAT;
 793        ccw->flags = 0;
 794        ccw->count = sizeof(*features);
 795        ccw->cda = (__u32)(unsigned long)features;
 796        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
 797        if (ret == 0)
 798                rc |= (u64)le32_to_cpu(features->features) << 32;
 799
 800out_free:
 801        ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 802        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 803        return rc;
 804}
 805
 806static void ccw_transport_features(struct virtio_device *vdev)
 807{
 808        /*
 809         * Currently nothing to do here.
 810         */
 811}
 812
 813static int virtio_ccw_finalize_features(struct virtio_device *vdev)
 814{
 815        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 816        struct virtio_feature_desc *features;
 817        struct ccw1 *ccw;
 818        int ret;
 819
 820        if (vcdev->revision >= 1 &&
 821            !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
 822                dev_err(&vdev->dev, "virtio: device uses revision 1 "
 823                        "but does not have VIRTIO_F_VERSION_1\n");
 824                return -EINVAL;
 825        }
 826
 827        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 828        if (!ccw)
 829                return -ENOMEM;
 830
 831        features = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*features));
 832        if (!features) {
 833                ret = -ENOMEM;
 834                goto out_free;
 835        }
 836        /* Give virtio_ring a chance to accept features. */
 837        vring_transport_features(vdev);
 838
 839        /* Give virtio_ccw a chance to accept features. */
 840        ccw_transport_features(vdev);
 841
 842        features->index = 0;
 843        features->features = cpu_to_le32((u32)vdev->features);
 844        /* Write the first half of the feature bits to the host. */
 845        ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 846        ccw->flags = 0;
 847        ccw->count = sizeof(*features);
 848        ccw->cda = (__u32)(unsigned long)features;
 849        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 850        if (ret)
 851                goto out_free;
 852
 853        if (vcdev->revision == 0)
 854                goto out_free;
 855
 856        features->index = 1;
 857        features->features = cpu_to_le32(vdev->features >> 32);
 858        /* Write the second half of the feature bits to the host. */
 859        ccw->cmd_code = CCW_CMD_WRITE_FEAT;
 860        ccw->flags = 0;
 861        ccw->count = sizeof(*features);
 862        ccw->cda = (__u32)(unsigned long)features;
 863        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
 864
 865out_free:
 866        ccw_device_dma_free(vcdev->cdev, features, sizeof(*features));
 867        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 868
 869        return ret;
 870}
 871
 872static void virtio_ccw_get_config(struct virtio_device *vdev,
 873                                  unsigned int offset, void *buf, unsigned len)
 874{
 875        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 876        int ret;
 877        struct ccw1 *ccw;
 878        void *config_area;
 879        unsigned long flags;
 880
 881        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 882        if (!ccw)
 883                return;
 884
 885        config_area = ccw_device_dma_zalloc(vcdev->cdev,
 886                                            VIRTIO_CCW_CONFIG_SIZE);
 887        if (!config_area)
 888                goto out_free;
 889
 890        /* Read the config area from the host. */
 891        ccw->cmd_code = CCW_CMD_READ_CONF;
 892        ccw->flags = 0;
 893        ccw->count = offset + len;
 894        ccw->cda = (__u32)(unsigned long)config_area;
 895        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
 896        if (ret)
 897                goto out_free;
 898
 899        spin_lock_irqsave(&vcdev->lock, flags);
 900        memcpy(vcdev->config, config_area, offset + len);
 901        if (vcdev->config_ready < offset + len)
 902                vcdev->config_ready = offset + len;
 903        spin_unlock_irqrestore(&vcdev->lock, flags);
 904        if (buf)
 905                memcpy(buf, config_area + offset, len);
 906
 907out_free:
 908        ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 909        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 910}
 911
 912static void virtio_ccw_set_config(struct virtio_device *vdev,
 913                                  unsigned int offset, const void *buf,
 914                                  unsigned len)
 915{
 916        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 917        struct ccw1 *ccw;
 918        void *config_area;
 919        unsigned long flags;
 920
 921        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 922        if (!ccw)
 923                return;
 924
 925        config_area = ccw_device_dma_zalloc(vcdev->cdev,
 926                                            VIRTIO_CCW_CONFIG_SIZE);
 927        if (!config_area)
 928                goto out_free;
 929
 930        /* Make sure we don't overwrite fields. */
 931        if (vcdev->config_ready < offset)
 932                virtio_ccw_get_config(vdev, 0, NULL, offset);
 933        spin_lock_irqsave(&vcdev->lock, flags);
 934        memcpy(&vcdev->config[offset], buf, len);
 935        /* Write the config area to the host. */
 936        memcpy(config_area, vcdev->config, sizeof(vcdev->config));
 937        spin_unlock_irqrestore(&vcdev->lock, flags);
 938        ccw->cmd_code = CCW_CMD_WRITE_CONF;
 939        ccw->flags = 0;
 940        ccw->count = offset + len;
 941        ccw->cda = (__u32)(unsigned long)config_area;
 942        ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
 943
 944out_free:
 945        ccw_device_dma_free(vcdev->cdev, config_area, VIRTIO_CCW_CONFIG_SIZE);
 946        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 947}
 948
 949static u8 virtio_ccw_get_status(struct virtio_device *vdev)
 950{
 951        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 952        u8 old_status = vcdev->dma_area->status;
 953        struct ccw1 *ccw;
 954
 955        if (vcdev->revision < 2)
 956                return vcdev->dma_area->status;
 957
 958        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 959        if (!ccw)
 960                return old_status;
 961
 962        ccw->cmd_code = CCW_CMD_READ_STATUS;
 963        ccw->flags = 0;
 964        ccw->count = sizeof(vcdev->dma_area->status);
 965        ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 966        ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS);
 967/*
 968 * If the channel program failed (should only happen if the device
 969 * was hotunplugged, and then we clean up via the machine check
 970 * handler anyway), vcdev->dma_area->status was not overwritten and we just
 971 * return the old status, which is fine.
 972*/
 973        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
 974
 975        return vcdev->dma_area->status;
 976}
 977
 978static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
 979{
 980        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
 981        u8 old_status = vcdev->dma_area->status;
 982        struct ccw1 *ccw;
 983        int ret;
 984
 985        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
 986        if (!ccw)
 987                return;
 988
 989        /* Write the status to the host. */
 990        vcdev->dma_area->status = status;
 991        ccw->cmd_code = CCW_CMD_WRITE_STATUS;
 992        ccw->flags = 0;
 993        ccw->count = sizeof(status);
 994        ccw->cda = (__u32)(unsigned long)&vcdev->dma_area->status;
 995        ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
 996        /* Write failed? We assume status is unchanged. */
 997        if (ret)
 998                vcdev->dma_area->status = old_status;
 999        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1000}
1001
1002static const char *virtio_ccw_bus_name(struct virtio_device *vdev)
1003{
1004        struct virtio_ccw_device *vcdev = to_vc_device(vdev);
1005
1006        return dev_name(&vcdev->cdev->dev);
1007}
1008
1009static const struct virtio_config_ops virtio_ccw_config_ops = {
1010        .get_features = virtio_ccw_get_features,
1011        .finalize_features = virtio_ccw_finalize_features,
1012        .get = virtio_ccw_get_config,
1013        .set = virtio_ccw_set_config,
1014        .get_status = virtio_ccw_get_status,
1015        .set_status = virtio_ccw_set_status,
1016        .reset = virtio_ccw_reset,
1017        .find_vqs = virtio_ccw_find_vqs,
1018        .del_vqs = virtio_ccw_del_vqs,
1019        .bus_name = virtio_ccw_bus_name,
1020};
1021
1022
1023/*
1024 * ccw bus driver related functions
1025 */
1026
1027static void virtio_ccw_release_dev(struct device *_d)
1028{
1029        struct virtio_device *dev = dev_to_virtio(_d);
1030        struct virtio_ccw_device *vcdev = to_vc_device(dev);
1031
1032        ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1033                            sizeof(*vcdev->dma_area));
1034        kfree(vcdev);
1035}
1036
1037static int irb_is_error(struct irb *irb)
1038{
1039        if (scsw_cstat(&irb->scsw) != 0)
1040                return 1;
1041        if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
1042                return 1;
1043        if (scsw_cc(&irb->scsw) != 0)
1044                return 1;
1045        return 0;
1046}
1047
1048static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
1049                                              int index)
1050{
1051        struct virtio_ccw_vq_info *info;
1052        unsigned long flags;
1053        struct virtqueue *vq;
1054
1055        vq = NULL;
1056        spin_lock_irqsave(&vcdev->lock, flags);
1057        list_for_each_entry(info, &vcdev->virtqueues, node) {
1058                if (info->vq->index == index) {
1059                        vq = info->vq;
1060                        break;
1061                }
1062        }
1063        spin_unlock_irqrestore(&vcdev->lock, flags);
1064        return vq;
1065}
1066
1067static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
1068                                      __u32 activity)
1069{
1070        if (vcdev->curr_io & activity) {
1071                switch (activity) {
1072                case VIRTIO_CCW_DOING_READ_FEAT:
1073                case VIRTIO_CCW_DOING_WRITE_FEAT:
1074                case VIRTIO_CCW_DOING_READ_CONFIG:
1075                case VIRTIO_CCW_DOING_WRITE_CONFIG:
1076                case VIRTIO_CCW_DOING_WRITE_STATUS:
1077                case VIRTIO_CCW_DOING_READ_STATUS:
1078                case VIRTIO_CCW_DOING_SET_VQ:
1079                case VIRTIO_CCW_DOING_SET_IND:
1080                case VIRTIO_CCW_DOING_SET_CONF_IND:
1081                case VIRTIO_CCW_DOING_RESET:
1082                case VIRTIO_CCW_DOING_READ_VQ_CONF:
1083                case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
1084                case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
1085                        vcdev->curr_io &= ~activity;
1086                        wake_up(&vcdev->wait_q);
1087                        break;
1088                default:
1089                        /* don't know what to do... */
1090                        dev_warn(&vcdev->cdev->dev,
1091                                 "Suspicious activity '%08x'\n", activity);
1092                        WARN_ON(1);
1093                        break;
1094                }
1095        }
1096}
1097
1098static void virtio_ccw_int_handler(struct ccw_device *cdev,
1099                                   unsigned long intparm,
1100                                   struct irb *irb)
1101{
1102        __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
1103        struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1104        int i;
1105        struct virtqueue *vq;
1106
1107        if (!vcdev)
1108                return;
1109        if (IS_ERR(irb)) {
1110                vcdev->err = PTR_ERR(irb);
1111                virtio_ccw_check_activity(vcdev, activity);
1112                /* Don't poke around indicators, something's wrong. */
1113                return;
1114        }
1115        /* Check if it's a notification from the host. */
1116        if ((intparm == 0) &&
1117            (scsw_stctl(&irb->scsw) ==
1118             (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
1119                /* OK */
1120        }
1121        if (irb_is_error(irb)) {
1122                /* Command reject? */
1123                if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
1124                    (irb->ecw[0] & SNS0_CMD_REJECT))
1125                        vcdev->err = -EOPNOTSUPP;
1126                else
1127                        /* Map everything else to -EIO. */
1128                        vcdev->err = -EIO;
1129        }
1130        virtio_ccw_check_activity(vcdev, activity);
1131        for_each_set_bit(i, indicators(vcdev),
1132                         sizeof(*indicators(vcdev)) * BITS_PER_BYTE) {
1133                /* The bit clear must happen before the vring kick. */
1134                clear_bit(i, indicators(vcdev));
1135                barrier();
1136                vq = virtio_ccw_vq_by_ind(vcdev, i);
1137                vring_interrupt(0, vq);
1138        }
1139        if (test_bit(0, indicators2(vcdev))) {
1140                virtio_config_changed(&vcdev->vdev);
1141                clear_bit(0, indicators2(vcdev));
1142        }
1143}
1144
1145/*
1146 * We usually want to autoonline all devices, but give the admin
1147 * a way to exempt devices from this.
1148 */
1149#define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
1150                     (8*sizeof(long)))
1151static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
1152
1153static char *no_auto = "";
1154
1155module_param(no_auto, charp, 0444);
1156MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
1157
1158static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
1159{
1160        struct ccw_dev_id id;
1161
1162        ccw_device_get_id(cdev, &id);
1163        if (test_bit(id.devno, devs_no_auto[id.ssid]))
1164                return 0;
1165        return 1;
1166}
1167
1168static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
1169{
1170        struct ccw_device *cdev = data;
1171        int ret;
1172
1173        ret = ccw_device_set_online(cdev);
1174        if (ret)
1175                dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
1176}
1177
1178static int virtio_ccw_probe(struct ccw_device *cdev)
1179{
1180        cdev->handler = virtio_ccw_int_handler;
1181
1182        if (virtio_ccw_check_autoonline(cdev))
1183                async_schedule(virtio_ccw_auto_online, cdev);
1184        return 0;
1185}
1186
1187static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
1188{
1189        unsigned long flags;
1190        struct virtio_ccw_device *vcdev;
1191
1192        spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1193        vcdev = dev_get_drvdata(&cdev->dev);
1194        if (!vcdev || vcdev->going_away) {
1195                spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1196                return NULL;
1197        }
1198        vcdev->going_away = true;
1199        spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1200        return vcdev;
1201}
1202
1203static void virtio_ccw_remove(struct ccw_device *cdev)
1204{
1205        unsigned long flags;
1206        struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1207
1208        if (vcdev && cdev->online) {
1209                if (vcdev->device_lost)
1210                        virtio_break_device(&vcdev->vdev);
1211                unregister_virtio_device(&vcdev->vdev);
1212                spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1213                dev_set_drvdata(&cdev->dev, NULL);
1214                spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1215        }
1216        cdev->handler = NULL;
1217}
1218
1219static int virtio_ccw_offline(struct ccw_device *cdev)
1220{
1221        unsigned long flags;
1222        struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
1223
1224        if (!vcdev)
1225                return 0;
1226        if (vcdev->device_lost)
1227                virtio_break_device(&vcdev->vdev);
1228        unregister_virtio_device(&vcdev->vdev);
1229        spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1230        dev_set_drvdata(&cdev->dev, NULL);
1231        spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1232        return 0;
1233}
1234
1235static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
1236{
1237        struct virtio_rev_info *rev;
1238        struct ccw1 *ccw;
1239        int ret;
1240
1241        ccw = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*ccw));
1242        if (!ccw)
1243                return -ENOMEM;
1244        rev = ccw_device_dma_zalloc(vcdev->cdev, sizeof(*rev));
1245        if (!rev) {
1246                ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1247                return -ENOMEM;
1248        }
1249
1250        /* Set transport revision */
1251        ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
1252        ccw->flags = 0;
1253        ccw->count = sizeof(*rev);
1254        ccw->cda = (__u32)(unsigned long)rev;
1255
1256        vcdev->revision = VIRTIO_CCW_REV_MAX;
1257        do {
1258                rev->revision = vcdev->revision;
1259                /* none of our supported revisions carry payload */
1260                rev->length = 0;
1261                ret = ccw_io_helper(vcdev, ccw,
1262                                    VIRTIO_CCW_DOING_SET_VIRTIO_REV);
1263                if (ret == -EOPNOTSUPP) {
1264                        if (vcdev->revision == 0)
1265                                /*
1266                                 * The host device does not support setting
1267                                 * the revision: let's operate it in legacy
1268                                 * mode.
1269                                 */
1270                                ret = 0;
1271                        else
1272                                vcdev->revision--;
1273                }
1274        } while (ret == -EOPNOTSUPP);
1275
1276        ccw_device_dma_free(vcdev->cdev, ccw, sizeof(*ccw));
1277        ccw_device_dma_free(vcdev->cdev, rev, sizeof(*rev));
1278        return ret;
1279}
1280
1281static int virtio_ccw_online(struct ccw_device *cdev)
1282{
1283        int ret;
1284        struct virtio_ccw_device *vcdev;
1285        unsigned long flags;
1286
1287        vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
1288        if (!vcdev) {
1289                dev_warn(&cdev->dev, "Could not get memory for virtio\n");
1290                ret = -ENOMEM;
1291                goto out_free;
1292        }
1293        vcdev->vdev.dev.parent = &cdev->dev;
1294        vcdev->cdev = cdev;
1295        vcdev->dma_area = ccw_device_dma_zalloc(vcdev->cdev,
1296                                                sizeof(*vcdev->dma_area));
1297        if (!vcdev->dma_area) {
1298                ret = -ENOMEM;
1299                goto out_free;
1300        }
1301
1302        vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
1303
1304        vcdev->vdev.dev.release = virtio_ccw_release_dev;
1305        vcdev->vdev.config = &virtio_ccw_config_ops;
1306        init_waitqueue_head(&vcdev->wait_q);
1307        INIT_LIST_HEAD(&vcdev->virtqueues);
1308        spin_lock_init(&vcdev->lock);
1309        mutex_init(&vcdev->io_lock);
1310
1311        spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1312        dev_set_drvdata(&cdev->dev, vcdev);
1313        spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1314        vcdev->vdev.id.vendor = cdev->id.cu_type;
1315        vcdev->vdev.id.device = cdev->id.cu_model;
1316
1317        ret = virtio_ccw_set_transport_rev(vcdev);
1318        if (ret)
1319                goto out_free;
1320
1321        ret = register_virtio_device(&vcdev->vdev);
1322        if (ret) {
1323                dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
1324                         ret);
1325                goto out_put;
1326        }
1327        return 0;
1328out_put:
1329        spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
1330        dev_set_drvdata(&cdev->dev, NULL);
1331        spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
1332        put_device(&vcdev->vdev.dev);
1333        return ret;
1334out_free:
1335        if (vcdev) {
1336                ccw_device_dma_free(vcdev->cdev, vcdev->dma_area,
1337                                    sizeof(*vcdev->dma_area));
1338        }
1339        kfree(vcdev);
1340        return ret;
1341}
1342
1343static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
1344{
1345        int rc;
1346        struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
1347
1348        /*
1349         * Make sure vcdev is set
1350         * i.e. set_offline/remove callback not already running
1351         */
1352        if (!vcdev)
1353                return NOTIFY_DONE;
1354
1355        switch (event) {
1356        case CIO_GONE:
1357                vcdev->device_lost = true;
1358                rc = NOTIFY_DONE;
1359                break;
1360        case CIO_OPER:
1361                rc = NOTIFY_OK;
1362                break;
1363        default:
1364                rc = NOTIFY_DONE;
1365                break;
1366        }
1367        return rc;
1368}
1369
1370static struct ccw_device_id virtio_ids[] = {
1371        { CCW_DEVICE(0x3832, 0) },
1372        {},
1373};
1374
1375static struct ccw_driver virtio_ccw_driver = {
1376        .driver = {
1377                .owner = THIS_MODULE,
1378                .name = "virtio_ccw",
1379        },
1380        .ids = virtio_ids,
1381        .probe = virtio_ccw_probe,
1382        .remove = virtio_ccw_remove,
1383        .set_offline = virtio_ccw_offline,
1384        .set_online = virtio_ccw_online,
1385        .notify = virtio_ccw_cio_notify,
1386        .int_class = IRQIO_VIR,
1387};
1388
1389static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
1390                           int max_digit, int max_val)
1391{
1392        int diff;
1393
1394        diff = 0;
1395        *val = 0;
1396
1397        while (diff <= max_digit) {
1398                int value = hex_to_bin(**cp);
1399
1400                if (value < 0)
1401                        break;
1402                *val = *val * 16 + value;
1403                (*cp)++;
1404                diff++;
1405        }
1406
1407        if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
1408                return 1;
1409
1410        return 0;
1411}
1412
1413static int __init parse_busid(char *str, unsigned int *cssid,
1414                              unsigned int *ssid, unsigned int *devno)
1415{
1416        char *str_work;
1417        int rc, ret;
1418
1419        rc = 1;
1420
1421        if (*str == '\0')
1422                goto out;
1423
1424        str_work = str;
1425        ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
1426        if (ret || (str_work[0] != '.'))
1427                goto out;
1428        str_work++;
1429        ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
1430        if (ret || (str_work[0] != '.'))
1431                goto out;
1432        str_work++;
1433        ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
1434        if (ret || (str_work[0] != '\0'))
1435                goto out;
1436
1437        rc = 0;
1438out:
1439        return rc;
1440}
1441
1442static void __init no_auto_parse(void)
1443{
1444        unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
1445        char *parm, *str;
1446        int rc;
1447
1448        str = no_auto;
1449        while ((parm = strsep(&str, ","))) {
1450                rc = parse_busid(strsep(&parm, "-"), &from_cssid,
1451                                 &from_ssid, &from);
1452                if (rc)
1453                        continue;
1454                if (parm != NULL) {
1455                        rc = parse_busid(parm, &to_cssid,
1456                                         &to_ssid, &to);
1457                        if ((from_ssid > to_ssid) ||
1458                            ((from_ssid == to_ssid) && (from > to)))
1459                                rc = -EINVAL;
1460                } else {
1461                        to_cssid = from_cssid;
1462                        to_ssid = from_ssid;
1463                        to = from;
1464                }
1465                if (rc)
1466                        continue;
1467                while ((from_ssid < to_ssid) ||
1468                       ((from_ssid == to_ssid) && (from <= to))) {
1469                        set_bit(from, devs_no_auto[from_ssid]);
1470                        from++;
1471                        if (from > __MAX_SUBCHANNEL) {
1472                                from_ssid++;
1473                                from = 0;
1474                        }
1475                }
1476        }
1477}
1478
1479static int __init virtio_ccw_init(void)
1480{
1481        int rc;
1482
1483        /* parse no_auto string before we do anything further */
1484        no_auto_parse();
1485
1486        summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
1487        if (!summary_indicators)
1488                return -ENOMEM;
1489        rc = ccw_driver_register(&virtio_ccw_driver);
1490        if (rc)
1491                cio_dma_free(summary_indicators, MAX_AIRQ_AREAS);
1492        return rc;
1493}
1494device_initcall(virtio_ccw_init);
1495