--- /dev/null
+/*
+ * ccw based virtio transport
+ *
+ * Copyright IBM Corp. 2012, 2014
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License (version 2 only)
+ * as published by the Free Software Foundation.
+ *
+ * Author(s): Cornelia Huck <cornelia.huck@de.ibm.com>
+ */
+
+#include <linux/kernel_stat.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/err.h>
+#include <linux/virtio.h>
+#include <linux/virtio_config.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/virtio_ring.h>
+#include <linux/pfn.h>
+#include <linux/async.h>
+#include <linux/wait.h>
+#include <linux/list.h>
+#include <linux/bitops.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/kvm_para.h>
+#include <linux/notifier.h>
+#include <asm/diag.h>
+#include <asm/setup.h>
+#include <asm/irq.h>
+#include <asm/cio.h>
+#include <asm/ccwdev.h>
+#include <asm/virtio-ccw.h>
+#include <asm/isc.h>
+#include <asm/airq.h>
+
+/*
+ * virtio related functions
+ */
+
+struct vq_config_block {
+ __u16 index;
+ __u16 num;
+} __packed;
+
+#define VIRTIO_CCW_CONFIG_SIZE 0x100
+/* same as PCI config space size, should be enough for all drivers */
+
+struct virtio_ccw_device {
+ struct virtio_device vdev;
+ __u8 *status;
+ __u8 config[VIRTIO_CCW_CONFIG_SIZE];
+ struct ccw_device *cdev;
+ __u32 curr_io;
+ int err;
+ unsigned int revision; /* Transport revision */
+ wait_queue_head_t wait_q;
+ spinlock_t lock;
+ struct list_head virtqueues;
+ unsigned long indicators;
+ unsigned long indicators2;
+ struct vq_config_block *config_block;
+ bool is_thinint;
+ bool going_away;
+ bool device_lost;
+ unsigned int config_ready;
+ void *airq_info;
+};
+
+struct vq_info_block_legacy {
+ __u64 queue;
+ __u32 align;
+ __u16 index;
+ __u16 num;
+} __packed;
+
+struct vq_info_block {
+ __u64 desc;
+ __u32 res0;
+ __u16 index;
+ __u16 num;
+ __u64 avail;
+ __u64 used;
+} __packed;
+
+struct virtio_feature_desc {
+ __u32 features;
+ __u8 index;
+} __packed;
+
+struct virtio_thinint_area {
+ unsigned long summary_indicator;
+ unsigned long indicator;
+ u64 bit_nr;
+ u8 isc;
+} __packed;
+
+struct virtio_rev_info {
+ __u16 revision;
+ __u16 length;
+ __u8 data[];
+};
+
+/* the highest virtio-ccw revision we support */
+#define VIRTIO_CCW_REV_MAX 1
+
+struct virtio_ccw_vq_info {
+ struct virtqueue *vq;
+ int num;
+ void *queue;
+ union {
+ struct vq_info_block s;
+ struct vq_info_block_legacy l;
+ } *info_block;
+ int bit_nr;
+ struct list_head node;
+ long cookie;
+};
+
+#define VIRTIO_AIRQ_ISC IO_SCH_ISC /* inherit from subchannel */
+
+#define VIRTIO_IV_BITS (L1_CACHE_BYTES * 8)
+#define MAX_AIRQ_AREAS 20
+
+static int virtio_ccw_use_airq = 1;
+
+struct airq_info {
+ rwlock_t lock;
+ u8 summary_indicator;
+ struct airq_struct airq;
+ struct airq_iv *aiv;
+};
+static struct airq_info *airq_areas[MAX_AIRQ_AREAS];
+
+#define CCW_CMD_SET_VQ 0x13
+#define CCW_CMD_VDEV_RESET 0x33
+#define CCW_CMD_SET_IND 0x43
+#define CCW_CMD_SET_CONF_IND 0x53
+#define CCW_CMD_READ_FEAT 0x12
+#define CCW_CMD_WRITE_FEAT 0x11
+#define CCW_CMD_READ_CONF 0x22
+#define CCW_CMD_WRITE_CONF 0x21
+#define CCW_CMD_WRITE_STATUS 0x31
+#define CCW_CMD_READ_VQ_CONF 0x32
+#define CCW_CMD_SET_IND_ADAPTER 0x73
+#define CCW_CMD_SET_VIRTIO_REV 0x83
+
+#define VIRTIO_CCW_DOING_SET_VQ 0x00010000
+#define VIRTIO_CCW_DOING_RESET 0x00040000
+#define VIRTIO_CCW_DOING_READ_FEAT 0x00080000
+#define VIRTIO_CCW_DOING_WRITE_FEAT 0x00100000
+#define VIRTIO_CCW_DOING_READ_CONFIG 0x00200000
+#define VIRTIO_CCW_DOING_WRITE_CONFIG 0x00400000
+#define VIRTIO_CCW_DOING_WRITE_STATUS 0x00800000
+#define VIRTIO_CCW_DOING_SET_IND 0x01000000
+#define VIRTIO_CCW_DOING_READ_VQ_CONF 0x02000000
+#define VIRTIO_CCW_DOING_SET_CONF_IND 0x04000000
+#define VIRTIO_CCW_DOING_SET_IND_ADAPTER 0x08000000
+#define VIRTIO_CCW_DOING_SET_VIRTIO_REV 0x10000000
+#define VIRTIO_CCW_INTPARM_MASK 0xffff0000
+
+static struct virtio_ccw_device *to_vc_device(struct virtio_device *vdev)
+{
+ return container_of(vdev, struct virtio_ccw_device, vdev);
+}
+
+static void drop_airq_indicator(struct virtqueue *vq, struct airq_info *info)
+{
+ unsigned long i, flags;
+
+ write_lock_irqsave(&info->lock, flags);
+ for (i = 0; i < airq_iv_end(info->aiv); i++) {
+ if (vq == (void *)airq_iv_get_ptr(info->aiv, i)) {
+ airq_iv_free_bit(info->aiv, i);
+ airq_iv_set_ptr(info->aiv, i, 0);
+ break;
+ }
+ }
+ write_unlock_irqrestore(&info->lock, flags);
+}
+
+static void virtio_airq_handler(struct airq_struct *airq)
+{
+ struct airq_info *info = container_of(airq, struct airq_info, airq);
+ unsigned long ai;
+
+ inc_irq_stat(IRQIO_VAI);
+ read_lock(&info->lock);
+ /* Walk through indicators field, summary indicator active. */
+ for (ai = 0;;) {
+ ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
+ if (ai == -1UL)
+ break;
+ vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
+ }
+ info->summary_indicator = 0;
+ smp_wmb();
+ /* Walk through indicators field, summary indicator not active. */
+ for (ai = 0;;) {
+ ai = airq_iv_scan(info->aiv, ai, airq_iv_end(info->aiv));
+ if (ai == -1UL)
+ break;
+ vring_interrupt(0, (void *)airq_iv_get_ptr(info->aiv, ai));
+ }
+ read_unlock(&info->lock);
+}
+
+static struct airq_info *new_airq_info(void)
+{
+ struct airq_info *info;
+ int rc;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return NULL;
+ rwlock_init(&info->lock);
+ info->aiv = airq_iv_create(VIRTIO_IV_BITS, AIRQ_IV_ALLOC | AIRQ_IV_PTR);
+ if (!info->aiv) {
+ kfree(info);
+ return NULL;
+ }
+ info->airq.handler = virtio_airq_handler;
+ info->airq.lsi_ptr = &info->summary_indicator;
+ info->airq.lsi_mask = 0xff;
+ info->airq.isc = VIRTIO_AIRQ_ISC;
+ rc = register_adapter_interrupt(&info->airq);
+ if (rc) {
+ airq_iv_release(info->aiv);
+ kfree(info);
+ return NULL;
+ }
+ return info;
+}
+
+static void destroy_airq_info(struct airq_info *info)
+{
+ if (!info)
+ return;
+
+ unregister_adapter_interrupt(&info->airq);
+ airq_iv_release(info->aiv);
+ kfree(info);
+}
+
+static unsigned long get_airq_indicator(struct virtqueue *vqs[], int nvqs,
+ u64 *first, void **airq_info)
+{
+ int i, j;
+ struct airq_info *info;
+ unsigned long indicator_addr = 0;
+ unsigned long bit, flags;
+
+ for (i = 0; i < MAX_AIRQ_AREAS && !indicator_addr; i++) {
+ if (!airq_areas[i])
+ airq_areas[i] = new_airq_info();
+ info = airq_areas[i];
+ if (!info)
+ return 0;
+ write_lock_irqsave(&info->lock, flags);
+ bit = airq_iv_alloc(info->aiv, nvqs);
+ if (bit == -1UL) {
+ /* Not enough vacancies. */
+ write_unlock_irqrestore(&info->lock, flags);
+ continue;
+ }
+ *first = bit;
+ *airq_info = info;
+ indicator_addr = (unsigned long)info->aiv->vector;
+ for (j = 0; j < nvqs; j++) {
+ airq_iv_set_ptr(info->aiv, bit + j,
+ (unsigned long)vqs[j]);
+ }
+ write_unlock_irqrestore(&info->lock, flags);
+ }
+ return indicator_addr;
+}
+
+static void virtio_ccw_drop_indicators(struct virtio_ccw_device *vcdev)
+{
+ struct virtio_ccw_vq_info *info;
+
+ list_for_each_entry(info, &vcdev->virtqueues, node)
+ drop_airq_indicator(info->vq, vcdev->airq_info);
+}
+
+static int doing_io(struct virtio_ccw_device *vcdev, __u32 flag)
+{
+ unsigned long flags;
+ __u32 ret;
+
+ spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
+ if (vcdev->err)
+ ret = 0;
+ else
+ ret = vcdev->curr_io & flag;
+ spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
+ return ret;
+}
+
+static int ccw_io_helper(struct virtio_ccw_device *vcdev,
+ struct ccw1 *ccw, __u32 intparm)
+{
+ int ret;
+ unsigned long flags;
+ int flag = intparm & VIRTIO_CCW_INTPARM_MASK;
+
+ do {
+ spin_lock_irqsave(get_ccwdev_lock(vcdev->cdev), flags);
+ ret = ccw_device_start(vcdev->cdev, ccw, intparm, 0, 0);
+ if (!ret) {
+ if (!vcdev->curr_io)
+ vcdev->err = 0;
+ vcdev->curr_io |= flag;
+ }
+ spin_unlock_irqrestore(get_ccwdev_lock(vcdev->cdev), flags);
+ cpu_relax();
+ } while (ret == -EBUSY);
+ wait_event(vcdev->wait_q, doing_io(vcdev, flag) == 0);
+ return ret ? ret : vcdev->err;
+}
+
+static void virtio_ccw_drop_indicator(struct virtio_ccw_device *vcdev,
+ struct ccw1 *ccw)
+{
+ int ret;
+ unsigned long *indicatorp = NULL;
+ struct virtio_thinint_area *thinint_area = NULL;
+ struct airq_info *airq_info = vcdev->airq_info;
+
+ if (vcdev->is_thinint) {
+ thinint_area = kzalloc(sizeof(*thinint_area),
+ GFP_DMA | GFP_KERNEL);
+ if (!thinint_area)
+ return;
+ thinint_area->summary_indicator =
+ (unsigned long) &airq_info->summary_indicator;
+ thinint_area->isc = VIRTIO_AIRQ_ISC;
+ ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
+ ccw->count = sizeof(*thinint_area);
+ ccw->cda = (__u32)(unsigned long) thinint_area;
+ } else {
+ indicatorp = kmalloc(sizeof(&vcdev->indicators),
+ GFP_DMA | GFP_KERNEL);
+ if (!indicatorp)
+ return;
+ *indicatorp = 0;
+ ccw->cmd_code = CCW_CMD_SET_IND;
+ ccw->count = sizeof(vcdev->indicators);
+ ccw->cda = (__u32)(unsigned long) indicatorp;
+ }
+ /* Deregister indicators from host. */
+ vcdev->indicators = 0;
+ ccw->flags = 0;
+ ret = ccw_io_helper(vcdev, ccw,
+ vcdev->is_thinint ?
+ VIRTIO_CCW_DOING_SET_IND_ADAPTER :
+ VIRTIO_CCW_DOING_SET_IND);
+ if (ret && (ret != -ENODEV))
+ dev_info(&vcdev->cdev->dev,
+ "Failed to deregister indicators (%d)\n", ret);
+ else if (vcdev->is_thinint)
+ virtio_ccw_drop_indicators(vcdev);
+ kfree(indicatorp);
+ kfree(thinint_area);
+}
+
+static inline long __do_kvm_notify(struct subchannel_id schid,
+ unsigned long queue_index,
+ long cookie)
+{
+ register unsigned long __nr asm("1") = KVM_S390_VIRTIO_CCW_NOTIFY;
+ register struct subchannel_id __schid asm("2") = schid;
+ register unsigned long __index asm("3") = queue_index;
+ register long __rc asm("2");
+ register long __cookie asm("4") = cookie;
+
+ asm volatile ("diag 2,4,0x500\n"
+ : "=d" (__rc) : "d" (__nr), "d" (__schid), "d" (__index),
+ "d"(__cookie)
+ : "memory", "cc");
+ return __rc;
+}
+
+static inline long do_kvm_notify(struct subchannel_id schid,
+ unsigned long queue_index,
+ long cookie)
+{
+ diag_stat_inc(DIAG_STAT_X500);
+ return __do_kvm_notify(schid, queue_index, cookie);
+}
+
+static bool virtio_ccw_kvm_notify(struct virtqueue *vq)
+{
+ struct virtio_ccw_vq_info *info = vq->priv;
+ struct virtio_ccw_device *vcdev;
+ struct subchannel_id schid;
+
+ vcdev = to_vc_device(info->vq->vdev);
+ ccw_device_get_schid(vcdev->cdev, &schid);
+ info->cookie = do_kvm_notify(schid, vq->index, info->cookie);
+ if (info->cookie < 0)
+ return false;
+ return true;
+}
+
+static int virtio_ccw_read_vq_conf(struct virtio_ccw_device *vcdev,
+ struct ccw1 *ccw, int index)
+{
+ int ret;
+
+ vcdev->config_block->index = index;
+ ccw->cmd_code = CCW_CMD_READ_VQ_CONF;
+ ccw->flags = 0;
+ ccw->count = sizeof(struct vq_config_block);
+ ccw->cda = (__u32)(unsigned long)(vcdev->config_block);
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_VQ_CONF);
+ if (ret)
+ return ret;
+ return vcdev->config_block->num;
+}
+
+static void virtio_ccw_del_vq(struct virtqueue *vq, struct ccw1 *ccw)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vq->vdev);
+ struct virtio_ccw_vq_info *info = vq->priv;
+ unsigned long flags;
+ unsigned long size;
+ int ret;
+ unsigned int index = vq->index;
+
+ /* Remove from our list. */
+ spin_lock_irqsave(&vcdev->lock, flags);
+ list_del(&info->node);
+ spin_unlock_irqrestore(&vcdev->lock, flags);
+
+ /* Release from host. */
+ if (vcdev->revision == 0) {
+ info->info_block->l.queue = 0;
+ info->info_block->l.align = 0;
+ info->info_block->l.index = index;
+ info->info_block->l.num = 0;
+ ccw->count = sizeof(info->info_block->l);
+ } else {
+ info->info_block->s.desc = 0;
+ info->info_block->s.index = index;
+ info->info_block->s.num = 0;
+ info->info_block->s.avail = 0;
+ info->info_block->s.used = 0;
+ ccw->count = sizeof(info->info_block->s);
+ }
+ ccw->cmd_code = CCW_CMD_SET_VQ;
+ ccw->flags = 0;
+ ccw->cda = (__u32)(unsigned long)(info->info_block);
+ ret = ccw_io_helper(vcdev, ccw,
+ VIRTIO_CCW_DOING_SET_VQ | index);
+ /*
+ * -ENODEV isn't considered an error: The device is gone anyway.
+ * This may happen on device detach.
+ */
+ if (ret && (ret != -ENODEV))
+ dev_warn(&vq->vdev->dev, "Error %d while deleting queue %d",
+ ret, index);
+
+ vring_del_virtqueue(vq);
+ size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
+ free_pages_exact(info->queue, size);
+ kfree(info->info_block);
+ kfree(info);
+}
+
+static void virtio_ccw_del_vqs(struct virtio_device *vdev)
+{
+ struct virtqueue *vq, *n;
+ struct ccw1 *ccw;
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return;
+
+ virtio_ccw_drop_indicator(vcdev, ccw);
+
+ list_for_each_entry_safe(vq, n, &vdev->vqs, list)
+ virtio_ccw_del_vq(vq, ccw);
+
+ kfree(ccw);
+}
+
+static struct virtqueue *virtio_ccw_setup_vq(struct virtio_device *vdev,
+ int i, vq_callback_t *callback,
+ const char *name,
+ struct ccw1 *ccw)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ int err;
+ struct virtqueue *vq = NULL;
+ struct virtio_ccw_vq_info *info;
+ unsigned long size = 0; /* silence the compiler */
+ unsigned long flags;
+
+ /* Allocate queue. */
+ info = kzalloc(sizeof(struct virtio_ccw_vq_info), GFP_KERNEL);
+ if (!info) {
+ dev_warn(&vcdev->cdev->dev, "no info\n");
+ err = -ENOMEM;
+ goto out_err;
+ }
+ info->info_block = kzalloc(sizeof(*info->info_block),
+ GFP_DMA | GFP_KERNEL);
+ if (!info->info_block) {
+ dev_warn(&vcdev->cdev->dev, "no info block\n");
+ err = -ENOMEM;
+ goto out_err;
+ }
+ info->num = virtio_ccw_read_vq_conf(vcdev, ccw, i);
+ if (info->num < 0) {
+ err = info->num;
+ goto out_err;
+ }
+ size = PAGE_ALIGN(vring_size(info->num, KVM_VIRTIO_CCW_RING_ALIGN));
+ info->queue = alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
+ if (info->queue == NULL) {
+ dev_warn(&vcdev->cdev->dev, "no queue\n");
+ err = -ENOMEM;
+ goto out_err;
+ }
+
+ vq = vring_new_virtqueue(i, info->num, KVM_VIRTIO_CCW_RING_ALIGN, vdev,
+ true, info->queue, virtio_ccw_kvm_notify,
+ callback, name);
+ if (!vq) {
+ /* For now, we fail if we can't get the requested size. */
+ dev_warn(&vcdev->cdev->dev, "no vq\n");
+ err = -ENOMEM;
+ goto out_err;
+ }
+
+ /* Register it with the host. */
+ if (vcdev->revision == 0) {
+ info->info_block->l.queue = (__u64)info->queue;
+ info->info_block->l.align = KVM_VIRTIO_CCW_RING_ALIGN;
+ info->info_block->l.index = i;
+ info->info_block->l.num = info->num;
+ ccw->count = sizeof(info->info_block->l);
+ } else {
+ info->info_block->s.desc = (__u64)info->queue;
+ info->info_block->s.index = i;
+ info->info_block->s.num = info->num;
+ info->info_block->s.avail = (__u64)virtqueue_get_avail(vq);
+ info->info_block->s.used = (__u64)virtqueue_get_used(vq);
+ ccw->count = sizeof(info->info_block->s);
+ }
+ ccw->cmd_code = CCW_CMD_SET_VQ;
+ ccw->flags = 0;
+ ccw->cda = (__u32)(unsigned long)(info->info_block);
+ err = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_VQ | i);
+ if (err) {
+ dev_warn(&vcdev->cdev->dev, "SET_VQ failed\n");
+ goto out_err;
+ }
+
+ info->vq = vq;
+ vq->priv = info;
+
+ /* Save it to our list. */
+ spin_lock_irqsave(&vcdev->lock, flags);
+ list_add(&info->node, &vcdev->virtqueues);
+ spin_unlock_irqrestore(&vcdev->lock, flags);
+
+ return vq;
+
+out_err:
+ if (vq)
+ vring_del_virtqueue(vq);
+ if (info) {
+ if (info->queue)
+ free_pages_exact(info->queue, size);
+ kfree(info->info_block);
+ }
+ kfree(info);
+ return ERR_PTR(err);
+}
+
+static int virtio_ccw_register_adapter_ind(struct virtio_ccw_device *vcdev,
+ struct virtqueue *vqs[], int nvqs,
+ struct ccw1 *ccw)
+{
+ int ret;
+ struct virtio_thinint_area *thinint_area = NULL;
+ struct airq_info *info;
+
+ thinint_area = kzalloc(sizeof(*thinint_area), GFP_DMA | GFP_KERNEL);
+ if (!thinint_area) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ /* Try to get an indicator. */
+ thinint_area->indicator = get_airq_indicator(vqs, nvqs,
+ &thinint_area->bit_nr,
+ &vcdev->airq_info);
+ if (!thinint_area->indicator) {
+ ret = -ENOSPC;
+ goto out;
+ }
+ info = vcdev->airq_info;
+ thinint_area->summary_indicator =
+ (unsigned long) &info->summary_indicator;
+ thinint_area->isc = VIRTIO_AIRQ_ISC;
+ ccw->cmd_code = CCW_CMD_SET_IND_ADAPTER;
+ ccw->flags = CCW_FLAG_SLI;
+ ccw->count = sizeof(*thinint_area);
+ ccw->cda = (__u32)(unsigned long)thinint_area;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND_ADAPTER);
+ if (ret) {
+ if (ret == -EOPNOTSUPP) {
+ /*
+ * The host does not support adapter interrupts
+ * for virtio-ccw, stop trying.
+ */
+ virtio_ccw_use_airq = 0;
+ pr_info("Adapter interrupts unsupported on host\n");
+ } else
+ dev_warn(&vcdev->cdev->dev,
+ "enabling adapter interrupts = %d\n", ret);
+ virtio_ccw_drop_indicators(vcdev);
+ }
+out:
+ kfree(thinint_area);
+ return ret;
+}
+
+static int virtio_ccw_find_vqs(struct virtio_device *vdev, unsigned nvqs,
+ struct virtqueue *vqs[],
+ vq_callback_t *callbacks[],
+ const char *names[])
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ unsigned long *indicatorp = NULL;
+ int ret, i;
+ struct ccw1 *ccw;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return -ENOMEM;
+
+ for (i = 0; i < nvqs; ++i) {
+ vqs[i] = virtio_ccw_setup_vq(vdev, i, callbacks[i], names[i],
+ ccw);
+ if (IS_ERR(vqs[i])) {
+ ret = PTR_ERR(vqs[i]);
+ vqs[i] = NULL;
+ goto out;
+ }
+ }
+ ret = -ENOMEM;
+ /* We need a data area under 2G to communicate. */
+ indicatorp = kmalloc(sizeof(&vcdev->indicators), GFP_DMA | GFP_KERNEL);
+ if (!indicatorp)
+ goto out;
+ *indicatorp = (unsigned long) &vcdev->indicators;
+ if (vcdev->is_thinint) {
+ ret = virtio_ccw_register_adapter_ind(vcdev, vqs, nvqs, ccw);
+ if (ret)
+ /* no error, just fall back to legacy interrupts */
+ vcdev->is_thinint = 0;
+ }
+ if (!vcdev->is_thinint) {
+ /* Register queue indicators with host. */
+ vcdev->indicators = 0;
+ ccw->cmd_code = CCW_CMD_SET_IND;
+ ccw->flags = 0;
+ ccw->count = sizeof(vcdev->indicators);
+ ccw->cda = (__u32)(unsigned long) indicatorp;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_IND);
+ if (ret)
+ goto out;
+ }
+ /* Register indicators2 with host for config changes */
+ *indicatorp = (unsigned long) &vcdev->indicators2;
+ vcdev->indicators2 = 0;
+ ccw->cmd_code = CCW_CMD_SET_CONF_IND;
+ ccw->flags = 0;
+ ccw->count = sizeof(vcdev->indicators2);
+ ccw->cda = (__u32)(unsigned long) indicatorp;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_SET_CONF_IND);
+ if (ret)
+ goto out;
+
+ kfree(indicatorp);
+ kfree(ccw);
+ return 0;
+out:
+ kfree(indicatorp);
+ kfree(ccw);
+ virtio_ccw_del_vqs(vdev);
+ return ret;
+}
+
+static void virtio_ccw_reset(struct virtio_device *vdev)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ struct ccw1 *ccw;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return;
+
+ /* Zero status bits. */
+ *vcdev->status = 0;
+
+ /* Send a reset ccw on device. */
+ ccw->cmd_code = CCW_CMD_VDEV_RESET;
+ ccw->flags = 0;
+ ccw->count = 0;
+ ccw->cda = 0;
+ ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_RESET);
+ kfree(ccw);
+}
+
+static u64 virtio_ccw_get_features(struct virtio_device *vdev)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ struct virtio_feature_desc *features;
+ int ret;
+ u64 rc;
+ struct ccw1 *ccw;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return 0;
+
+ features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
+ if (!features) {
+ rc = 0;
+ goto out_free;
+ }
+ /* Read the feature bits from the host. */
+ features->index = 0;
+ ccw->cmd_code = CCW_CMD_READ_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
+ if (ret) {
+ rc = 0;
+ goto out_free;
+ }
+
+ rc = le32_to_cpu(features->features);
+
+ if (vcdev->revision == 0)
+ goto out_free;
+
+ /* Read second half of the feature bits from the host. */
+ features->index = 1;
+ ccw->cmd_code = CCW_CMD_READ_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_FEAT);
+ if (ret == 0)
+ rc |= (u64)le32_to_cpu(features->features) << 32;
+
+out_free:
+ kfree(features);
+ kfree(ccw);
+ return rc;
+}
+
+static int virtio_ccw_finalize_features(struct virtio_device *vdev)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ struct virtio_feature_desc *features;
+ struct ccw1 *ccw;
+ int ret;
+
+ if (vcdev->revision >= 1 &&
+ !__virtio_test_bit(vdev, VIRTIO_F_VERSION_1)) {
+ dev_err(&vdev->dev, "virtio: device uses revision 1 "
+ "but does not have VIRTIO_F_VERSION_1\n");
+ return -EINVAL;
+ }
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return -ENOMEM;
+
+ features = kzalloc(sizeof(*features), GFP_DMA | GFP_KERNEL);
+ if (!features) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+ /* Give virtio_ring a chance to accept features. */
+ vring_transport_features(vdev);
+
+ features->index = 0;
+ features->features = cpu_to_le32((u32)vdev->features);
+ /* Write the first half of the feature bits to the host. */
+ ccw->cmd_code = CCW_CMD_WRITE_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
+ if (ret)
+ goto out_free;
+
+ if (vcdev->revision == 0)
+ goto out_free;
+
+ features->index = 1;
+ features->features = cpu_to_le32(vdev->features >> 32);
+ /* Write the second half of the feature bits to the host. */
+ ccw->cmd_code = CCW_CMD_WRITE_FEAT;
+ ccw->flags = 0;
+ ccw->count = sizeof(*features);
+ ccw->cda = (__u32)(unsigned long)features;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_FEAT);
+
+out_free:
+ kfree(features);
+ kfree(ccw);
+
+ return ret;
+}
+
+static void virtio_ccw_get_config(struct virtio_device *vdev,
+ unsigned int offset, void *buf, unsigned len)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ int ret;
+ struct ccw1 *ccw;
+ void *config_area;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return;
+
+ config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
+ if (!config_area)
+ goto out_free;
+
+ /* Read the config area from the host. */
+ ccw->cmd_code = CCW_CMD_READ_CONF;
+ ccw->flags = 0;
+ ccw->count = offset + len;
+ ccw->cda = (__u32)(unsigned long)config_area;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_CONFIG);
+ if (ret)
+ goto out_free;
+
+ memcpy(vcdev->config, config_area, offset + len);
+ if (buf)
+ memcpy(buf, &vcdev->config[offset], len);
+ if (vcdev->config_ready < offset + len)
+ vcdev->config_ready = offset + len;
+
+out_free:
+ kfree(config_area);
+ kfree(ccw);
+}
+
+static void virtio_ccw_set_config(struct virtio_device *vdev,
+ unsigned int offset, const void *buf,
+ unsigned len)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ struct ccw1 *ccw;
+ void *config_area;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return;
+
+ config_area = kzalloc(VIRTIO_CCW_CONFIG_SIZE, GFP_DMA | GFP_KERNEL);
+ if (!config_area)
+ goto out_free;
+
+ /* Make sure we don't overwrite fields. */
+ if (vcdev->config_ready < offset)
+ virtio_ccw_get_config(vdev, 0, NULL, offset);
+ memcpy(&vcdev->config[offset], buf, len);
+ /* Write the config area to the host. */
+ memcpy(config_area, vcdev->config, sizeof(vcdev->config));
+ ccw->cmd_code = CCW_CMD_WRITE_CONF;
+ ccw->flags = 0;
+ ccw->count = offset + len;
+ ccw->cda = (__u32)(unsigned long)config_area;
+ ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_CONFIG);
+
+out_free:
+ kfree(config_area);
+ kfree(ccw);
+}
+
+static u8 virtio_ccw_get_status(struct virtio_device *vdev)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+
+ return *vcdev->status;
+}
+
+static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status)
+{
+ struct virtio_ccw_device *vcdev = to_vc_device(vdev);
+ u8 old_status = *vcdev->status;
+ struct ccw1 *ccw;
+ int ret;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return;
+
+ /* Write the status to the host. */
+ *vcdev->status = status;
+ ccw->cmd_code = CCW_CMD_WRITE_STATUS;
+ ccw->flags = 0;
+ ccw->count = sizeof(status);
+ ccw->cda = (__u32)(unsigned long)vcdev->status;
+ ret = ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_WRITE_STATUS);
+ /* Write failed? We assume status is unchanged. */
+ if (ret)
+ *vcdev->status = old_status;
+ kfree(ccw);
+}
+
+static struct virtio_config_ops virtio_ccw_config_ops = {
+ .get_features = virtio_ccw_get_features,
+ .finalize_features = virtio_ccw_finalize_features,
+ .get = virtio_ccw_get_config,
+ .set = virtio_ccw_set_config,
+ .get_status = virtio_ccw_get_status,
+ .set_status = virtio_ccw_set_status,
+ .reset = virtio_ccw_reset,
+ .find_vqs = virtio_ccw_find_vqs,
+ .del_vqs = virtio_ccw_del_vqs,
+};
+
+
+/*
+ * ccw bus driver related functions
+ */
+
+static void virtio_ccw_release_dev(struct device *_d)
+{
+ struct virtio_device *dev = container_of(_d, struct virtio_device,
+ dev);
+ struct virtio_ccw_device *vcdev = to_vc_device(dev);
+
+ kfree(vcdev->status);
+ kfree(vcdev->config_block);
+ kfree(vcdev);
+}
+
+static int irb_is_error(struct irb *irb)
+{
+ if (scsw_cstat(&irb->scsw) != 0)
+ return 1;
+ if (scsw_dstat(&irb->scsw) & ~(DEV_STAT_CHN_END | DEV_STAT_DEV_END))
+ return 1;
+ if (scsw_cc(&irb->scsw) != 0)
+ return 1;
+ return 0;
+}
+
+static struct virtqueue *virtio_ccw_vq_by_ind(struct virtio_ccw_device *vcdev,
+ int index)
+{
+ struct virtio_ccw_vq_info *info;
+ unsigned long flags;
+ struct virtqueue *vq;
+
+ vq = NULL;
+ spin_lock_irqsave(&vcdev->lock, flags);
+ list_for_each_entry(info, &vcdev->virtqueues, node) {
+ if (info->vq->index == index) {
+ vq = info->vq;
+ break;
+ }
+ }
+ spin_unlock_irqrestore(&vcdev->lock, flags);
+ return vq;
+}
+
+static void virtio_ccw_check_activity(struct virtio_ccw_device *vcdev,
+ __u32 activity)
+{
+ if (vcdev->curr_io & activity) {
+ switch (activity) {
+ case VIRTIO_CCW_DOING_READ_FEAT:
+ case VIRTIO_CCW_DOING_WRITE_FEAT:
+ case VIRTIO_CCW_DOING_READ_CONFIG:
+ case VIRTIO_CCW_DOING_WRITE_CONFIG:
+ case VIRTIO_CCW_DOING_WRITE_STATUS:
+ case VIRTIO_CCW_DOING_SET_VQ:
+ case VIRTIO_CCW_DOING_SET_IND:
+ case VIRTIO_CCW_DOING_SET_CONF_IND:
+ case VIRTIO_CCW_DOING_RESET:
+ case VIRTIO_CCW_DOING_READ_VQ_CONF:
+ case VIRTIO_CCW_DOING_SET_IND_ADAPTER:
+ case VIRTIO_CCW_DOING_SET_VIRTIO_REV:
+ vcdev->curr_io &= ~activity;
+ wake_up(&vcdev->wait_q);
+ break;
+ default:
+ /* don't know what to do... */
+ dev_warn(&vcdev->cdev->dev,
+ "Suspicious activity '%08x'\n", activity);
+ WARN_ON(1);
+ break;
+ }
+ }
+}
+
+static void virtio_ccw_int_handler(struct ccw_device *cdev,
+ unsigned long intparm,
+ struct irb *irb)
+{
+ __u32 activity = intparm & VIRTIO_CCW_INTPARM_MASK;
+ struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
+ int i;
+ struct virtqueue *vq;
+
+ if (!vcdev)
+ return;
+ if (IS_ERR(irb)) {
+ vcdev->err = PTR_ERR(irb);
+ virtio_ccw_check_activity(vcdev, activity);
+ /* Don't poke around indicators, something's wrong. */
+ return;
+ }
+ /* Check if it's a notification from the host. */
+ if ((intparm == 0) &&
+ (scsw_stctl(&irb->scsw) ==
+ (SCSW_STCTL_ALERT_STATUS | SCSW_STCTL_STATUS_PEND))) {
+ /* OK */
+ }
+ if (irb_is_error(irb)) {
+ /* Command reject? */
+ if ((scsw_dstat(&irb->scsw) & DEV_STAT_UNIT_CHECK) &&
+ (irb->ecw[0] & SNS0_CMD_REJECT))
+ vcdev->err = -EOPNOTSUPP;
+ else
+ /* Map everything else to -EIO. */
+ vcdev->err = -EIO;
+ }
+ virtio_ccw_check_activity(vcdev, activity);
+ for_each_set_bit(i, &vcdev->indicators,
+ sizeof(vcdev->indicators) * BITS_PER_BYTE) {
+ /* The bit clear must happen before the vring kick. */
+ clear_bit(i, &vcdev->indicators);
+ barrier();
+ vq = virtio_ccw_vq_by_ind(vcdev, i);
+ vring_interrupt(0, vq);
+ }
+ if (test_bit(0, &vcdev->indicators2)) {
+ virtio_config_changed(&vcdev->vdev);
+ clear_bit(0, &vcdev->indicators2);
+ }
+}
+
+/*
+ * We usually want to autoonline all devices, but give the admin
+ * a way to exempt devices from this.
+ */
+#define __DEV_WORDS ((__MAX_SUBCHANNEL + (8*sizeof(long) - 1)) / \
+ (8*sizeof(long)))
+static unsigned long devs_no_auto[__MAX_SSID + 1][__DEV_WORDS];
+
+static char *no_auto = "";
+
+module_param(no_auto, charp, 0444);
+MODULE_PARM_DESC(no_auto, "list of ccw bus id ranges not to be auto-onlined");
+
+static int virtio_ccw_check_autoonline(struct ccw_device *cdev)
+{
+ struct ccw_dev_id id;
+
+ ccw_device_get_id(cdev, &id);
+ if (test_bit(id.devno, devs_no_auto[id.ssid]))
+ return 0;
+ return 1;
+}
+
+static void virtio_ccw_auto_online(void *data, async_cookie_t cookie)
+{
+ struct ccw_device *cdev = data;
+ int ret;
+
+ ret = ccw_device_set_online(cdev);
+ if (ret)
+ dev_warn(&cdev->dev, "Failed to set online: %d\n", ret);
+}
+
+static int virtio_ccw_probe(struct ccw_device *cdev)
+{
+ cdev->handler = virtio_ccw_int_handler;
+
+ if (virtio_ccw_check_autoonline(cdev))
+ async_schedule(virtio_ccw_auto_online, cdev);
+ return 0;
+}
+
+static struct virtio_ccw_device *virtio_grab_drvdata(struct ccw_device *cdev)
+{
+ unsigned long flags;
+ struct virtio_ccw_device *vcdev;
+
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ vcdev = dev_get_drvdata(&cdev->dev);
+ if (!vcdev || vcdev->going_away) {
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ return NULL;
+ }
+ vcdev->going_away = true;
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ return vcdev;
+}
+
+static void virtio_ccw_remove(struct ccw_device *cdev)
+{
+ unsigned long flags;
+ struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
+
+ if (vcdev && cdev->online) {
+ if (vcdev->device_lost)
+ virtio_break_device(&vcdev->vdev);
+ unregister_virtio_device(&vcdev->vdev);
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ dev_set_drvdata(&cdev->dev, NULL);
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ }
+ cdev->handler = NULL;
+}
+
+static int virtio_ccw_offline(struct ccw_device *cdev)
+{
+ unsigned long flags;
+ struct virtio_ccw_device *vcdev = virtio_grab_drvdata(cdev);
+
+ if (!vcdev)
+ return 0;
+ if (vcdev->device_lost)
+ virtio_break_device(&vcdev->vdev);
+ unregister_virtio_device(&vcdev->vdev);
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ dev_set_drvdata(&cdev->dev, NULL);
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ return 0;
+}
+
+static int virtio_ccw_set_transport_rev(struct virtio_ccw_device *vcdev)
+{
+ struct virtio_rev_info *rev;
+ struct ccw1 *ccw;
+ int ret;
+
+ ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL);
+ if (!ccw)
+ return -ENOMEM;
+ rev = kzalloc(sizeof(*rev), GFP_DMA | GFP_KERNEL);
+ if (!rev) {
+ kfree(ccw);
+ return -ENOMEM;
+ }
+
+ /* Set transport revision */
+ ccw->cmd_code = CCW_CMD_SET_VIRTIO_REV;
+ ccw->flags = 0;
+ ccw->count = sizeof(*rev);
+ ccw->cda = (__u32)(unsigned long)rev;
+
+ vcdev->revision = VIRTIO_CCW_REV_MAX;
+ do {
+ rev->revision = vcdev->revision;
+ /* none of our supported revisions carry payload */
+ rev->length = 0;
+ ret = ccw_io_helper(vcdev, ccw,
+ VIRTIO_CCW_DOING_SET_VIRTIO_REV);
+ if (ret == -EOPNOTSUPP) {
+ if (vcdev->revision == 0)
+ /*
+ * The host device does not support setting
+ * the revision: let's operate it in legacy
+ * mode.
+ */
+ ret = 0;
+ else
+ vcdev->revision--;
+ }
+ } while (ret == -EOPNOTSUPP);
+
+ kfree(ccw);
+ kfree(rev);
+ return ret;
+}
+
+static int virtio_ccw_online(struct ccw_device *cdev)
+{
+ int ret;
+ struct virtio_ccw_device *vcdev;
+ unsigned long flags;
+
+ vcdev = kzalloc(sizeof(*vcdev), GFP_KERNEL);
+ if (!vcdev) {
+ dev_warn(&cdev->dev, "Could not get memory for virtio\n");
+ ret = -ENOMEM;
+ goto out_free;
+ }
+ vcdev->config_block = kzalloc(sizeof(*vcdev->config_block),
+ GFP_DMA | GFP_KERNEL);
+ if (!vcdev->config_block) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+ vcdev->status = kzalloc(sizeof(*vcdev->status), GFP_DMA | GFP_KERNEL);
+ if (!vcdev->status) {
+ ret = -ENOMEM;
+ goto out_free;
+ }
+
+ vcdev->is_thinint = virtio_ccw_use_airq; /* at least try */
+
+ vcdev->vdev.dev.parent = &cdev->dev;
+ vcdev->vdev.dev.release = virtio_ccw_release_dev;
+ vcdev->vdev.config = &virtio_ccw_config_ops;
+ vcdev->cdev = cdev;
+ init_waitqueue_head(&vcdev->wait_q);
+ INIT_LIST_HEAD(&vcdev->virtqueues);
+ spin_lock_init(&vcdev->lock);
+
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ dev_set_drvdata(&cdev->dev, vcdev);
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ vcdev->vdev.id.vendor = cdev->id.cu_type;
+ vcdev->vdev.id.device = cdev->id.cu_model;
+
+ ret = virtio_ccw_set_transport_rev(vcdev);
+ if (ret)
+ goto out_free;
+
+ ret = register_virtio_device(&vcdev->vdev);
+ if (ret) {
+ dev_warn(&cdev->dev, "Failed to register virtio device: %d\n",
+ ret);
+ goto out_put;
+ }
+ return 0;
+out_put:
+ spin_lock_irqsave(get_ccwdev_lock(cdev), flags);
+ dev_set_drvdata(&cdev->dev, NULL);
+ spin_unlock_irqrestore(get_ccwdev_lock(cdev), flags);
+ put_device(&vcdev->vdev.dev);
+ return ret;
+out_free:
+ if (vcdev) {
+ kfree(vcdev->status);
+ kfree(vcdev->config_block);
+ }
+ kfree(vcdev);
+ return ret;
+}
+
+static int virtio_ccw_cio_notify(struct ccw_device *cdev, int event)
+{
+ int rc;
+ struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev);
+
+ /*
+ * Make sure vcdev is set
+ * i.e. set_offline/remove callback not already running
+ */
+ if (!vcdev)
+ return NOTIFY_DONE;
+
+ switch (event) {
+ case CIO_GONE:
+ vcdev->device_lost = true;
+ rc = NOTIFY_DONE;
+ break;
+ default:
+ rc = NOTIFY_DONE;
+ break;
+ }
+ return rc;
+}
+
+static struct ccw_device_id virtio_ids[] = {
+ { CCW_DEVICE(0x3832, 0) },
+ {},
+};
+MODULE_DEVICE_TABLE(ccw, virtio_ids);
+
+static struct ccw_driver virtio_ccw_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "virtio_ccw",
+ },
+ .ids = virtio_ids,
+ .probe = virtio_ccw_probe,
+ .remove = virtio_ccw_remove,
+ .set_offline = virtio_ccw_offline,
+ .set_online = virtio_ccw_online,
+ .notify = virtio_ccw_cio_notify,
+ .int_class = IRQIO_VIR,
+};
+
+static int __init pure_hex(char **cp, unsigned int *val, int min_digit,
+ int max_digit, int max_val)
+{
+ int diff;
+
+ diff = 0;
+ *val = 0;
+
+ while (diff <= max_digit) {
+ int value = hex_to_bin(**cp);
+
+ if (value < 0)
+ break;
+ *val = *val * 16 + value;
+ (*cp)++;
+ diff++;
+ }
+
+ if ((diff < min_digit) || (diff > max_digit) || (*val > max_val))
+ return 1;
+
+ return 0;
+}
+
+static int __init parse_busid(char *str, unsigned int *cssid,
+ unsigned int *ssid, unsigned int *devno)
+{
+ char *str_work;
+ int rc, ret;
+
+ rc = 1;
+
+ if (*str == '\0')
+ goto out;
+
+ str_work = str;
+ ret = pure_hex(&str_work, cssid, 1, 2, __MAX_CSSID);
+ if (ret || (str_work[0] != '.'))
+ goto out;
+ str_work++;
+ ret = pure_hex(&str_work, ssid, 1, 1, __MAX_SSID);
+ if (ret || (str_work[0] != '.'))
+ goto out;
+ str_work++;
+ ret = pure_hex(&str_work, devno, 4, 4, __MAX_SUBCHANNEL);
+ if (ret || (str_work[0] != '\0'))
+ goto out;
+
+ rc = 0;
+out:
+ return rc;
+}
+
+static void __init no_auto_parse(void)
+{
+ unsigned int from_cssid, to_cssid, from_ssid, to_ssid, from, to;
+ char *parm, *str;
+ int rc;
+
+ str = no_auto;
+ while ((parm = strsep(&str, ","))) {
+ rc = parse_busid(strsep(&parm, "-"), &from_cssid,
+ &from_ssid, &from);
+ if (rc)
+ continue;
+ if (parm != NULL) {
+ rc = parse_busid(parm, &to_cssid,
+ &to_ssid, &to);
+ if ((from_ssid > to_ssid) ||
+ ((from_ssid == to_ssid) && (from > to)))
+ rc = -EINVAL;
+ } else {
+ to_cssid = from_cssid;
+ to_ssid = from_ssid;
+ to = from;
+ }
+ if (rc)
+ continue;
+ while ((from_ssid < to_ssid) ||
+ ((from_ssid == to_ssid) && (from <= to))) {
+ set_bit(from, devs_no_auto[from_ssid]);
+ from++;
+ if (from > __MAX_SUBCHANNEL) {
+ from_ssid++;
+ from = 0;
+ }
+ }
+ }
+}
+
+static int __init virtio_ccw_init(void)
+{
+ /* parse no_auto string before we do anything further */
+ no_auto_parse();
+ return ccw_driver_register(&virtio_ccw_driver);
+}
+module_init(virtio_ccw_init);
+
+static void __exit virtio_ccw_exit(void)
+{
+ int i;
+
+ ccw_driver_unregister(&virtio_ccw_driver);
+ for (i = 0; i < MAX_AIRQ_AREAS; i++)
+ destroy_airq_info(airq_areas[i]);
+}
+module_exit(virtio_ccw_exit);
Code Review / kvmfornfv.git / blobdiff