diff options
Diffstat (limited to 'drivers/s390/virtio/virtio_ccw.c')
| -rw-r--r-- | drivers/s390/virtio/virtio_ccw.c | 1467 |
1 files changed, 1467 insertions, 0 deletions
diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c new file mode 100644 index 000000000..0447ae278 --- /dev/null +++ b/drivers/s390/virtio/virtio_ccw.c @@ -0,0 +1,1467 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ccw based virtio transport + * + * Copyright IBM Corp. 2012, 2014 + * + * 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/moduleparam.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 mutex io_lock; /* Serializes I/O requests */ + 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 { + __le32 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 2 + +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]; +static DEFINE_MUTEX(airq_areas_lock); + +#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_READ_STATUS 0x72 +#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_DOING_READ_STATUS 0x20000000 +#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 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++) { + mutex_lock(&airq_areas_lock); + if (!airq_areas[i]) + airq_areas[i] = new_airq_info(); + info = airq_areas[i]; + mutex_unlock(&airq_areas_lock); + 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; + + if (!vcdev->airq_info) + return; + 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; + + mutex_lock(&vcdev->io_lock); + 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); + ret = ret ? ret : vcdev->err; + mutex_unlock(&vcdev->io_lock); + return ret; +} + +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 { + /* payload is the address of the indicators */ + 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 ?: -ENOENT; +} + +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\n", + 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, bool ctx, + 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, ctx, 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 * const names[], + const bool *ctx, + struct irq_affinity *desc) +{ + 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], + ctx ? ctx[i] : false, 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. Our payload is + * the address of the indicators. + */ + 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 = false; + } + 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; + unsigned long flags; + + 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; + + spin_lock_irqsave(&vcdev->lock, flags); + memcpy(vcdev->config, config_area, offset + len); + if (vcdev->config_ready < offset + len) + vcdev->config_ready = offset + len; + spin_unlock_irqrestore(&vcdev->lock, flags); + if (buf) + memcpy(buf, config_area + 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; + unsigned long flags; + + 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); + spin_lock_irqsave(&vcdev->lock, flags); + memcpy(&vcdev->config[offset], buf, len); + /* Write the config area to the host. */ + memcpy(config_area, vcdev->config, sizeof(vcdev->config)); + spin_unlock_irqrestore(&vcdev->lock, flags); + 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); + u8 old_status = *vcdev->status; + struct ccw1 *ccw; + + if (vcdev->revision < 2) + return *vcdev->status; + + ccw = kzalloc(sizeof(*ccw), GFP_DMA | GFP_KERNEL); + if (!ccw) + return old_status; + + ccw->cmd_code = CCW_CMD_READ_STATUS; + ccw->flags = 0; + ccw->count = sizeof(*vcdev->status); + ccw->cda = (__u32)(unsigned long)vcdev->status; + ccw_io_helper(vcdev, ccw, VIRTIO_CCW_DOING_READ_STATUS); +/* + * If the channel program failed (should only happen if the device + * was hotunplugged, and then we clean up via the machine check + * handler anyway), vcdev->status was not overwritten and we just + * return the old status, which is fine. +*/ + kfree(ccw); + + 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 const 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 = dev_to_virtio(_d); + 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_READ_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); + mutex_init(&vcdev->io_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; + case CIO_OPER: + rc = NOTIFY_OK; + break; + default: + rc = NOTIFY_DONE; + break; + } + return rc; +} + +static struct ccw_device_id virtio_ids[] = { + { CCW_DEVICE(0x3832, 0) }, + {}, +}; + +#ifdef CONFIG_PM_SLEEP +static int virtio_ccw_freeze(struct ccw_device *cdev) +{ + struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev); + + return virtio_device_freeze(&vcdev->vdev); +} + +static int virtio_ccw_restore(struct ccw_device *cdev) +{ + struct virtio_ccw_device *vcdev = dev_get_drvdata(&cdev->dev); + int ret; + + ret = virtio_ccw_set_transport_rev(vcdev); + if (ret) + return ret; + + return virtio_device_restore(&vcdev->vdev); +} +#endif + +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, +#ifdef CONFIG_PM_SLEEP + .freeze = virtio_ccw_freeze, + .thaw = virtio_ccw_restore, + .restore = virtio_ccw_restore, +#endif +}; + +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); +} +device_initcall(virtio_ccw_init); |