From 7fb2b2d512448cf0e914c4647a1cf02b52263702 Mon Sep 17 00:00:00 2001 From: Thomas Huth Date: Wed, 27 Sep 2017 13:42:01 +0200 Subject: [PATCH] s390/virtio: remove the old KVM virtio transport There is no recent user space application available anymore which still supports this old virtio transport. Additionally, commit 3b2fbb3f06ef ("virtio/s390: deprecate old transport") introduced a deprecation message in the driver, and apparently nobody complained so far that it is still required. So let's simply remove it. Signed-off-by: Thomas Huth Reviewed-by: Cornelia Huck Acked-by: Halil Pasic Signed-off-by: Heiko Carstens Signed-off-by: Martin Schwidefsky --- arch/s390/Kconfig | 13 - drivers/s390/virtio/Makefile | 3 - drivers/s390/virtio/kvm_virtio.c | 515 ------------------------------- 3 files changed, 531 deletions(-) delete mode 100644 drivers/s390/virtio/kvm_virtio.c diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig index 4edc91e6c3ff..5fd4a67c93b3 100644 --- a/arch/s390/Kconfig +++ b/arch/s390/Kconfig @@ -929,17 +929,4 @@ config S390_GUEST Select this option if you want to run the kernel as a guest under the KVM hypervisor. -config S390_GUEST_OLD_TRANSPORT - def_bool y - prompt "Guest support for old s390 virtio transport (DEPRECATED)" - depends on S390_GUEST - help - Enable this option to add support for the old s390-virtio - transport (i.e. virtio devices NOT based on virtio-ccw). This - type of virtio devices is only available on the experimental - kuli userspace or with old (< 2.6) qemu. If you are running - with a modern version of qemu (which supports virtio-ccw since - 1.4 and uses it by default since version 2.4), you probably won't - need this. - endmenu diff --git a/drivers/s390/virtio/Makefile b/drivers/s390/virtio/Makefile index df40692a9011..d9942e0a123c 100644 --- a/drivers/s390/virtio/Makefile +++ b/drivers/s390/virtio/Makefile @@ -7,7 +7,4 @@ # as published by the Free Software Foundation. s390-virtio-objs := virtio_ccw.o -ifdef CONFIG_S390_GUEST_OLD_TRANSPORT -s390-virtio-objs += kvm_virtio.o -endif obj-$(CONFIG_S390_GUEST) += $(s390-virtio-objs) diff --git a/drivers/s390/virtio/kvm_virtio.c b/drivers/s390/virtio/kvm_virtio.c deleted file mode 100644 index a99d09a11f05..000000000000 --- a/drivers/s390/virtio/kvm_virtio.c +++ /dev/null @@ -1,515 +0,0 @@ -/* - * virtio for kvm on s390 - * - * Copyright IBM Corp. 2008 - * - * 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): Christian Borntraeger - */ - -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#define VIRTIO_SUBCODE_64 0x0D00 - -/* - * The pointer to our (page) of device descriptions. - */ -static void *kvm_devices; -static struct work_struct hotplug_work; - -struct kvm_device { - struct virtio_device vdev; - struct kvm_device_desc *desc; -}; - -#define to_kvmdev(vd) container_of(vd, struct kvm_device, vdev) - -/* - * memory layout: - * - kvm_device_descriptor - * struct kvm_device_desc - * - configuration - * struct kvm_vqconfig - * - feature bits - * - config space - */ -static struct kvm_vqconfig *kvm_vq_config(const struct kvm_device_desc *desc) -{ - return (struct kvm_vqconfig *)(desc + 1); -} - -static u8 *kvm_vq_features(const struct kvm_device_desc *desc) -{ - return (u8 *)(kvm_vq_config(desc) + desc->num_vq); -} - -static u8 *kvm_vq_configspace(const struct kvm_device_desc *desc) -{ - return kvm_vq_features(desc) + desc->feature_len * 2; -} - -/* - * The total size of the config page used by this device (incl. desc) - */ -static unsigned desc_size(const struct kvm_device_desc *desc) -{ - return sizeof(*desc) - + desc->num_vq * sizeof(struct kvm_vqconfig) - + desc->feature_len * 2 - + desc->config_len; -} - -/* This gets the device's feature bits. */ -static u64 kvm_get_features(struct virtio_device *vdev) -{ - unsigned int i; - u32 features = 0; - struct kvm_device_desc *desc = to_kvmdev(vdev)->desc; - u8 *in_features = kvm_vq_features(desc); - - for (i = 0; i < min(desc->feature_len * 8, 32); i++) - if (in_features[i / 8] & (1 << (i % 8))) - features |= (1 << i); - return features; -} - -static int kvm_finalize_features(struct virtio_device *vdev) -{ - unsigned int i, bits; - struct kvm_device_desc *desc = to_kvmdev(vdev)->desc; - /* Second half of bitmap is features we accept. */ - u8 *out_features = kvm_vq_features(desc) + desc->feature_len; - - /* Give virtio_ring a chance to accept features. */ - vring_transport_features(vdev); - - /* Make sure we don't have any features > 32 bits! */ - BUG_ON((u32)vdev->features != vdev->features); - - memset(out_features, 0, desc->feature_len); - bits = min_t(unsigned, desc->feature_len, sizeof(vdev->features)) * 8; - for (i = 0; i < bits; i++) { - if (__virtio_test_bit(vdev, i)) - out_features[i / 8] |= (1 << (i % 8)); - } - - return 0; -} - -/* - * Reading and writing elements in config space - */ -static void kvm_get(struct virtio_device *vdev, unsigned int offset, - void *buf, unsigned len) -{ - struct kvm_device_desc *desc = to_kvmdev(vdev)->desc; - - BUG_ON(offset + len > desc->config_len); - memcpy(buf, kvm_vq_configspace(desc) + offset, len); -} - -static void kvm_set(struct virtio_device *vdev, unsigned int offset, - const void *buf, unsigned len) -{ - struct kvm_device_desc *desc = to_kvmdev(vdev)->desc; - - BUG_ON(offset + len > desc->config_len); - memcpy(kvm_vq_configspace(desc) + offset, buf, len); -} - -/* - * The operations to get and set the status word just access - * the status field of the device descriptor. set_status will also - * make a hypercall to the host, to tell about status changes - */ -static u8 kvm_get_status(struct virtio_device *vdev) -{ - return to_kvmdev(vdev)->desc->status; -} - -static void kvm_set_status(struct virtio_device *vdev, u8 status) -{ - BUG_ON(!status); - to_kvmdev(vdev)->desc->status = status; - kvm_hypercall1(KVM_S390_VIRTIO_SET_STATUS, - (unsigned long) to_kvmdev(vdev)->desc); -} - -/* - * To reset the device, we use the KVM_VIRTIO_RESET hypercall, using the - * descriptor address. The Host will zero the status and all the - * features. - */ -static void kvm_reset(struct virtio_device *vdev) -{ - kvm_hypercall1(KVM_S390_VIRTIO_RESET, - (unsigned long) to_kvmdev(vdev)->desc); -} - -/* - * When the virtio_ring code wants to notify the Host, it calls us here and we - * make a hypercall. We hand the address of the virtqueue so the Host - * knows which virtqueue we're talking about. - */ -static bool kvm_notify(struct virtqueue *vq) -{ - long rc; - struct kvm_vqconfig *config = vq->priv; - - rc = kvm_hypercall1(KVM_S390_VIRTIO_NOTIFY, config->address); - if (rc < 0) - return false; - return true; -} - -/* - * This routine finds the first virtqueue described in the configuration of - * this device and sets it up. - */ -static struct virtqueue *kvm_find_vq(struct virtio_device *vdev, - unsigned index, - void (*callback)(struct virtqueue *vq), - const char *name, bool ctx) -{ - struct kvm_device *kdev = to_kvmdev(vdev); - struct kvm_vqconfig *config; - struct virtqueue *vq; - int err; - - if (index >= kdev->desc->num_vq) - return ERR_PTR(-ENOENT); - - if (!name) - return NULL; - - config = kvm_vq_config(kdev->desc)+index; - - err = vmem_add_mapping(config->address, - vring_size(config->num, - KVM_S390_VIRTIO_RING_ALIGN)); - if (err) - goto out; - - vq = vring_new_virtqueue(index, config->num, KVM_S390_VIRTIO_RING_ALIGN, - vdev, true, ctx, (void *) config->address, - kvm_notify, callback, name); - if (!vq) { - err = -ENOMEM; - goto unmap; - } - - /* - * register a callback token - * The host will sent this via the external interrupt parameter - */ - config->token = (u64) vq; - - vq->priv = config; - return vq; -unmap: - vmem_remove_mapping(config->address, - vring_size(config->num, - KVM_S390_VIRTIO_RING_ALIGN)); -out: - return ERR_PTR(err); -} - -static void kvm_del_vq(struct virtqueue *vq) -{ - struct kvm_vqconfig *config = vq->priv; - - vring_del_virtqueue(vq); - vmem_remove_mapping(config->address, - vring_size(config->num, - KVM_S390_VIRTIO_RING_ALIGN)); -} - -static void kvm_del_vqs(struct virtio_device *vdev) -{ - struct virtqueue *vq, *n; - - list_for_each_entry_safe(vq, n, &vdev->vqs, list) - kvm_del_vq(vq); -} - -static int kvm_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 kvm_device *kdev = to_kvmdev(vdev); - int i; - - /* We must have this many virtqueues. */ - if (nvqs > kdev->desc->num_vq) - return -ENOENT; - - for (i = 0; i < nvqs; ++i) { - vqs[i] = kvm_find_vq(vdev, i, callbacks[i], names[i], - ctx ? ctx[i] : false); - if (IS_ERR(vqs[i])) - goto error; - } - return 0; - -error: - kvm_del_vqs(vdev); - return PTR_ERR(vqs[i]); -} - -static const char *kvm_bus_name(struct virtio_device *vdev) -{ - return ""; -} - -/* - * The config ops structure as defined by virtio config - */ -static const struct virtio_config_ops kvm_vq_configspace_ops = { - .get_features = kvm_get_features, - .finalize_features = kvm_finalize_features, - .get = kvm_get, - .set = kvm_set, - .get_status = kvm_get_status, - .set_status = kvm_set_status, - .reset = kvm_reset, - .find_vqs = kvm_find_vqs, - .del_vqs = kvm_del_vqs, - .bus_name = kvm_bus_name, -}; - -/* - * The root device for the kvm virtio devices. - * This makes them appear as /sys/devices/kvm_s390/0,1,2 not /sys/devices/0,1,2. - */ -static struct device *kvm_root; - -/* - * adds a new device and register it with virtio - * appropriate drivers are loaded by the device model - */ -static void add_kvm_device(struct kvm_device_desc *d, unsigned int offset) -{ - struct kvm_device *kdev; - - kdev = kzalloc(sizeof(*kdev), GFP_KERNEL); - if (!kdev) { - printk(KERN_EMERG "Cannot allocate kvm dev %u type %u\n", - offset, d->type); - return; - } - - kdev->vdev.dev.parent = kvm_root; - kdev->vdev.id.device = d->type; - kdev->vdev.config = &kvm_vq_configspace_ops; - kdev->desc = d; - - if (register_virtio_device(&kdev->vdev) != 0) { - printk(KERN_ERR "Failed to register kvm device %u type %u\n", - offset, d->type); - kfree(kdev); - } -} - -/* - * scan_devices() simply iterates through the device page. - * The type 0 is reserved to mean "end of devices". - */ -static void scan_devices(void) -{ - unsigned int i; - struct kvm_device_desc *d; - - for (i = 0; i < PAGE_SIZE; i += desc_size(d)) { - d = kvm_devices + i; - - if (d->type == 0) - break; - - add_kvm_device(d, i); - } -} - -/* - * match for a kvm device with a specific desc pointer - */ -static int match_desc(struct device *dev, void *data) -{ - struct virtio_device *vdev = dev_to_virtio(dev); - struct kvm_device *kdev = to_kvmdev(vdev); - - return kdev->desc == data; -} - -/* - * hotplug_device tries to find changes in the device page. - */ -static void hotplug_devices(struct work_struct *dummy) -{ - unsigned int i; - struct kvm_device_desc *d; - struct device *dev; - - for (i = 0; i < PAGE_SIZE; i += desc_size(d)) { - d = kvm_devices + i; - - /* end of list */ - if (d->type == 0) - break; - - /* device already exists */ - dev = device_find_child(kvm_root, d, match_desc); - if (dev) { - /* XXX check for hotplug remove */ - put_device(dev); - continue; - } - - /* new device */ - printk(KERN_INFO "Adding new virtio device %p\n", d); - add_kvm_device(d, i); - } -} - -/* - * we emulate the request_irq behaviour on top of s390 extints - */ -static void kvm_extint_handler(struct ext_code ext_code, - unsigned int param32, unsigned long param64) -{ - struct virtqueue *vq; - u32 param; - - if ((ext_code.subcode & 0xff00) != VIRTIO_SUBCODE_64) - return; - inc_irq_stat(IRQEXT_VRT); - - /* The LSB might be overloaded, we have to mask it */ - vq = (struct virtqueue *)(param64 & ~1UL); - - /* We use ext_params to decide what this interrupt means */ - param = param32 & VIRTIO_PARAM_MASK; - - switch (param) { - case VIRTIO_PARAM_CONFIG_CHANGED: - virtio_config_changed(vq->vdev); - break; - case VIRTIO_PARAM_DEV_ADD: - schedule_work(&hotplug_work); - break; - case VIRTIO_PARAM_VRING_INTERRUPT: - default: - vring_interrupt(0, vq); - break; - } -} - -/* - * For s390-virtio, we expect a page above main storage containing - * the virtio configuration. Try to actually load from this area - * in order to figure out if the host provides this page. - */ -static int __init test_devices_support(unsigned long addr) -{ - int ret = -EIO; - - asm volatile( - "0: lura 0,%1\n" - "1: xgr %0,%0\n" - "2:\n" - EX_TABLE(0b,2b) - EX_TABLE(1b,2b) - : "+d" (ret) - : "a" (addr) - : "0", "cc"); - return ret; -} -/* - * Init function for virtio - * devices are in a single page above top of "normal" + standby mem - */ -static int __init kvm_devices_init(void) -{ - int rc; - unsigned long total_memory_size = sclp.rzm * sclp.rnmax; - - if (!MACHINE_IS_KVM) - return -ENODEV; - - if (test_devices_support(total_memory_size) < 0) - return -ENODEV; - - pr_warn("The s390-virtio transport is deprecated. Please switch to a modern host providing virtio-ccw.\n"); - - rc = vmem_add_mapping(total_memory_size, PAGE_SIZE); - if (rc) - return rc; - - kvm_devices = (void *) total_memory_size; - - kvm_root = root_device_register("kvm_s390"); - if (IS_ERR(kvm_root)) { - rc = PTR_ERR(kvm_root); - printk(KERN_ERR "Could not register kvm_s390 root device"); - vmem_remove_mapping(total_memory_size, PAGE_SIZE); - return rc; - } - - INIT_WORK(&hotplug_work, hotplug_devices); - - irq_subclass_register(IRQ_SUBCLASS_SERVICE_SIGNAL); - register_external_irq(EXT_IRQ_CP_SERVICE, kvm_extint_handler); - - scan_devices(); - return 0; -} - -/* code for early console output with virtio_console */ -static int early_put_chars(u32 vtermno, const char *buf, int count) -{ - char scratch[17]; - unsigned int len = count; - - if (len > sizeof(scratch) - 1) - len = sizeof(scratch) - 1; - scratch[len] = '\0'; - memcpy(scratch, buf, len); - kvm_hypercall1(KVM_S390_VIRTIO_NOTIFY, __pa(scratch)); - return len; -} - -static int __init s390_virtio_console_init(void) -{ - if (sclp.has_vt220 || sclp.has_linemode) - return -ENODEV; - return virtio_cons_early_init(early_put_chars); -} -console_initcall(s390_virtio_console_init); - - -/* - * We do this after core stuff, but before the drivers. - */ -postcore_initcall(kvm_devices_init); -- GitLab