diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gvt/kvmgt.c')
| -rw-r--r-- | drivers/gpu/drm/i915/gvt/kvmgt.c | 597 |
1 files changed, 597 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c new file mode 100644 index 000000000000..dc0365033157 --- /dev/null +++ b/drivers/gpu/drm/i915/gvt/kvmgt.c @@ -0,0 +1,597 @@ +/* + * KVMGT - the implementation of Intel mediated pass-through framework for KVM + * + * Copyright(c) 2014-2016 Intel Corporation. All rights reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + * + * Authors: + * Kevin Tian <kevin.tian@intel.com> + * Jike Song <jike.song@intel.com> + * Xiaoguang Chen <xiaoguang.chen@intel.com> + */ + +#include <linux/init.h> +#include <linux/device.h> +#include <linux/mm.h> +#include <linux/types.h> +#include <linux/list.h> +#include <linux/rbtree.h> +#include <linux/spinlock.h> +#include <linux/eventfd.h> +#include <linux/uuid.h> +#include <linux/kvm_host.h> +#include <linux/vfio.h> + +#include "i915_drv.h" +#include "gvt.h" + +static inline long kvmgt_pin_pages(struct device *dev, unsigned long *user_pfn, + long npage, int prot, unsigned long *phys_pfn) +{ + return 0; +} +static inline long kvmgt_unpin_pages(struct device *dev, unsigned long *pfn, + long npage) +{ + return 0; +} + +static const struct intel_gvt_ops *intel_gvt_ops; + + +/* helper macros copied from vfio-pci */ +#define VFIO_PCI_OFFSET_SHIFT 40 +#define VFIO_PCI_OFFSET_TO_INDEX(off) (off >> VFIO_PCI_OFFSET_SHIFT) +#define VFIO_PCI_INDEX_TO_OFFSET(index) ((u64)(index) << VFIO_PCI_OFFSET_SHIFT) +#define VFIO_PCI_OFFSET_MASK (((u64)(1) << VFIO_PCI_OFFSET_SHIFT) - 1) + +struct vfio_region { + u32 type; + u32 subtype; + size_t size; + u32 flags; +}; + +struct kvmgt_pgfn { + gfn_t gfn; + struct hlist_node hnode; +}; + +struct kvmgt_guest_info { + struct kvm *kvm; + struct intel_vgpu *vgpu; + struct kvm_page_track_notifier_node track_node; +#define NR_BKT (1 << 18) + struct hlist_head ptable[NR_BKT]; +#undef NR_BKT +}; + +struct gvt_dma { + struct rb_node node; + gfn_t gfn; + kvm_pfn_t pfn; +}; + +static struct gvt_dma *__gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn) +{ + struct rb_node *node = vgpu->vdev.cache.rb_node; + struct gvt_dma *ret = NULL; + + while (node) { + struct gvt_dma *itr = rb_entry(node, struct gvt_dma, node); + + if (gfn < itr->gfn) + node = node->rb_left; + else if (gfn > itr->gfn) + node = node->rb_right; + else { + ret = itr; + goto out; + } + } + +out: + return ret; +} + +static kvm_pfn_t gvt_cache_find(struct intel_vgpu *vgpu, gfn_t gfn) +{ + struct gvt_dma *entry; + + mutex_lock(&vgpu->vdev.cache_lock); + entry = __gvt_cache_find(vgpu, gfn); + mutex_unlock(&vgpu->vdev.cache_lock); + + return entry == NULL ? 0 : entry->pfn; +} + +static void gvt_cache_add(struct intel_vgpu *vgpu, gfn_t gfn, kvm_pfn_t pfn) +{ + struct gvt_dma *new, *itr; + struct rb_node **link = &vgpu->vdev.cache.rb_node, *parent = NULL; + + new = kzalloc(sizeof(struct gvt_dma), GFP_KERNEL); + if (!new) + return; + + new->gfn = gfn; + new->pfn = pfn; + + mutex_lock(&vgpu->vdev.cache_lock); + while (*link) { + parent = *link; + itr = rb_entry(parent, struct gvt_dma, node); + + if (gfn == itr->gfn) + goto out; + else if (gfn < itr->gfn) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + + rb_link_node(&new->node, parent, link); + rb_insert_color(&new->node, &vgpu->vdev.cache); + mutex_unlock(&vgpu->vdev.cache_lock); + return; + +out: + mutex_unlock(&vgpu->vdev.cache_lock); + kfree(new); +} + +static void __gvt_cache_remove_entry(struct intel_vgpu *vgpu, + struct gvt_dma *entry) +{ + rb_erase(&entry->node, &vgpu->vdev.cache); + kfree(entry); +} + +static void gvt_cache_remove(struct intel_vgpu *vgpu, gfn_t gfn) +{ + struct device *dev = vgpu->vdev.mdev; + struct gvt_dma *this; + unsigned long pfn; + + mutex_lock(&vgpu->vdev.cache_lock); + this = __gvt_cache_find(vgpu, gfn); + if (!this) { + mutex_unlock(&vgpu->vdev.cache_lock); + return; + } + + pfn = this->pfn; + WARN_ON((kvmgt_unpin_pages(dev, &pfn, 1) != 1)); + __gvt_cache_remove_entry(vgpu, this); + mutex_unlock(&vgpu->vdev.cache_lock); +} + +static void gvt_cache_init(struct intel_vgpu *vgpu) +{ + vgpu->vdev.cache = RB_ROOT; + mutex_init(&vgpu->vdev.cache_lock); +} + +static void gvt_cache_destroy(struct intel_vgpu *vgpu) +{ + struct gvt_dma *dma; + struct rb_node *node = NULL; + struct device *dev = vgpu->vdev.mdev; + unsigned long pfn; + + mutex_lock(&vgpu->vdev.cache_lock); + while ((node = rb_first(&vgpu->vdev.cache))) { + dma = rb_entry(node, struct gvt_dma, node); + pfn = dma->pfn; + + kvmgt_unpin_pages(dev, &pfn, 1); + __gvt_cache_remove_entry(vgpu, dma); + } + mutex_unlock(&vgpu->vdev.cache_lock); +} + +static struct intel_vgpu_type *intel_gvt_find_vgpu_type(struct intel_gvt *gvt, + const char *name) +{ + int i; + struct intel_vgpu_type *t; + const char *driver_name = dev_driver_string( + &gvt->dev_priv->drm.pdev->dev); + + for (i = 0; i < gvt->num_types; i++) { + t = &gvt->types[i]; + if (!strncmp(t->name, name + strlen(driver_name) + 1, + sizeof(t->name))) + return t; + } + + return NULL; +} + +static struct attribute *type_attrs[] = { + NULL, +}; + +static struct attribute_group *intel_vgpu_type_groups[] = { + [0 ... NR_MAX_INTEL_VGPU_TYPES - 1] = NULL, +}; + +static bool intel_gvt_init_vgpu_type_groups(struct intel_gvt *gvt) +{ + int i, j; + struct intel_vgpu_type *type; + struct attribute_group *group; + + for (i = 0; i < gvt->num_types; i++) { + type = &gvt->types[i]; + + group = kzalloc(sizeof(struct attribute_group), GFP_KERNEL); + if (WARN_ON(!group)) + goto unwind; + + group->name = type->name; + group->attrs = type_attrs; + intel_vgpu_type_groups[i] = group; + } + + return true; + +unwind: + for (j = 0; j < i; j++) { + group = intel_vgpu_type_groups[j]; + kfree(group); + } + + return false; +} + +static void intel_gvt_cleanup_vgpu_type_groups(struct intel_gvt *gvt) +{ + int i; + struct attribute_group *group; + + for (i = 0; i < gvt->num_types; i++) { + group = intel_vgpu_type_groups[i]; + kfree(group); + } +} + +static void kvmgt_protect_table_init(struct kvmgt_guest_info *info) +{ + hash_init(info->ptable); +} + +static void kvmgt_protect_table_destroy(struct kvmgt_guest_info *info) +{ + struct kvmgt_pgfn *p; + struct hlist_node *tmp; + int i; + + hash_for_each_safe(info->ptable, i, tmp, p, hnode) { + hash_del(&p->hnode); + kfree(p); + } +} + +static struct kvmgt_pgfn * +__kvmgt_protect_table_find(struct kvmgt_guest_info *info, gfn_t gfn) +{ + struct kvmgt_pgfn *p, *res = NULL; + + hash_for_each_possible(info->ptable, p, hnode, gfn) { + if (gfn == p->gfn) { + res = p; + break; + } + } + + return res; +} + +static bool kvmgt_gfn_is_write_protected(struct kvmgt_guest_info *info, + gfn_t gfn) +{ + struct kvmgt_pgfn *p; + + p = __kvmgt_protect_table_find(info, gfn); + return !!p; +} + +static void kvmgt_protect_table_add(struct kvmgt_guest_info *info, gfn_t gfn) +{ + struct kvmgt_pgfn *p; + + if (kvmgt_gfn_is_write_protected(info, gfn)) + return; + + p = kmalloc(sizeof(struct kvmgt_pgfn), GFP_ATOMIC); + if (WARN(!p, "gfn: 0x%llx\n", gfn)) + return; + + p->gfn = gfn; + hash_add(info->ptable, &p->hnode, gfn); +} + +static void kvmgt_protect_table_del(struct kvmgt_guest_info *info, + gfn_t gfn) +{ + struct kvmgt_pgfn *p; + + p = __kvmgt_protect_table_find(info, gfn); + if (p) { + hash_del(&p->hnode); + kfree(p); + } +} + +static int kvmgt_host_init(struct device *dev, void *gvt, const void *ops) +{ + if (!intel_gvt_init_vgpu_type_groups(gvt)) + return -EFAULT; + + intel_gvt_ops = ops; + + /* MDEV is not yet available */ + return -ENODEV; +} + +static void kvmgt_host_exit(struct device *dev, void *gvt) +{ + intel_gvt_cleanup_vgpu_type_groups(gvt); +} + +static int kvmgt_write_protect_add(unsigned long handle, u64 gfn) +{ + struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle; + struct kvm *kvm = info->kvm; + struct kvm_memory_slot *slot; + int idx; + + idx = srcu_read_lock(&kvm->srcu); + slot = gfn_to_memslot(kvm, gfn); + + spin_lock(&kvm->mmu_lock); + + if (kvmgt_gfn_is_write_protected(info, gfn)) + goto out; + + kvm_slot_page_track_add_page(kvm, slot, gfn, KVM_PAGE_TRACK_WRITE); + kvmgt_protect_table_add(info, gfn); + +out: + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); + return 0; +} + +static int kvmgt_write_protect_remove(unsigned long handle, u64 gfn) +{ + struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle; + struct kvm *kvm = info->kvm; + struct kvm_memory_slot *slot; + int idx; + + idx = srcu_read_lock(&kvm->srcu); + slot = gfn_to_memslot(kvm, gfn); + + spin_lock(&kvm->mmu_lock); + + if (!kvmgt_gfn_is_write_protected(info, gfn)) + goto out; + + kvm_slot_page_track_remove_page(kvm, slot, gfn, KVM_PAGE_TRACK_WRITE); + kvmgt_protect_table_del(info, gfn); + +out: + spin_unlock(&kvm->mmu_lock); + srcu_read_unlock(&kvm->srcu, idx); + return 0; +} + +static void kvmgt_page_track_write(struct kvm_vcpu *vcpu, gpa_t gpa, + const u8 *val, int len, + struct kvm_page_track_notifier_node *node) +{ + struct kvmgt_guest_info *info = container_of(node, + struct kvmgt_guest_info, track_node); + + if (kvmgt_gfn_is_write_protected(info, gpa_to_gfn(gpa))) + intel_gvt_ops->emulate_mmio_write(info->vgpu, gpa, + (void *)val, len); +} + +static void kvmgt_page_track_flush_slot(struct kvm *kvm, + struct kvm_memory_slot *slot, + struct kvm_page_track_notifier_node *node) +{ + int i; + gfn_t gfn; + struct kvmgt_guest_info *info = container_of(node, + struct kvmgt_guest_info, track_node); + + spin_lock(&kvm->mmu_lock); + for (i = 0; i < slot->npages; i++) { + gfn = slot->base_gfn + i; + if (kvmgt_gfn_is_write_protected(info, gfn)) { + kvm_slot_page_track_remove_page(kvm, slot, gfn, + KVM_PAGE_TRACK_WRITE); + kvmgt_protect_table_del(info, gfn); + } + } + spin_unlock(&kvm->mmu_lock); +} + +static bool kvmgt_check_guest(void) +{ + unsigned int eax, ebx, ecx, edx; + char s[12]; + unsigned int *i; + + eax = KVM_CPUID_SIGNATURE; + ebx = ecx = edx = 0; + + asm volatile ("cpuid" + : "+a"(eax), "=b"(ebx), "=c"(ecx), "=d"(edx) + : + : "cc", "memory"); + i = (unsigned int *)s; + i[0] = ebx; + i[1] = ecx; + i[2] = edx; + + return !strncmp(s, "KVMKVMKVM", strlen("KVMKVMKVM")); +} + +/** + * NOTE: + * It's actually impossible to check if we are running in KVM host, + * since the "KVM host" is simply native. So we only dectect guest here. + */ +static int kvmgt_detect_host(void) +{ +#ifdef CONFIG_INTEL_IOMMU + if (intel_iommu_gfx_mapped) { + gvt_err("Hardware IOMMU compatibility not yet supported, try to boot with intel_iommu=igfx_off\n"); + return -ENODEV; + } +#endif + return kvmgt_check_guest() ? -ENODEV : 0; +} + +static int kvmgt_attach_vgpu(void *vgpu, unsigned long *handle) +{ + /* nothing to do here */ + return 0; +} + +static void kvmgt_detach_vgpu(unsigned long handle) +{ + /* nothing to do here */ +} + +static int kvmgt_inject_msi(unsigned long handle, u32 addr, u16 data) +{ + struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle; + struct intel_vgpu *vgpu = info->vgpu; + + if (vgpu->vdev.msi_trigger) + return eventfd_signal(vgpu->vdev.msi_trigger, 1) == 1; + + return false; +} + +static unsigned long kvmgt_gfn_to_pfn(unsigned long handle, unsigned long gfn) +{ + unsigned long pfn; + struct kvmgt_guest_info *info = (struct kvmgt_guest_info *)handle; + int rc; + + pfn = gvt_cache_find(info->vgpu, gfn); + if (pfn != 0) + return pfn; + + rc = kvmgt_pin_pages(info->vgpu->vdev.mdev, &gfn, 1, + IOMMU_READ | IOMMU_WRITE, &pfn); + if (rc != 1) { + gvt_err("vfio_pin_pages failed for gfn: 0x%lx\n", gfn); + return 0; + } + + gvt_cache_add(info->vgpu, gfn, pfn); + return pfn; +} + +static void *kvmgt_gpa_to_hva(unsigned long handle, unsigned long gpa) +{ + unsigned long pfn; + gfn_t gfn = gpa_to_gfn(gpa); + + pfn = kvmgt_gfn_to_pfn(handle, gfn); + if (!pfn) + return NULL; + + return (char *)pfn_to_kaddr(pfn) + offset_in_page(gpa); +} + +static int kvmgt_rw_gpa(unsigned long handle, unsigned long gpa, + void *buf, unsigned long len, bool write) +{ + void *hva = NULL; + + hva = kvmgt_gpa_to_hva(handle, gpa); + if (!hva) + return -EFAULT; + + if (write) + memcpy(hva, buf, len); + else + memcpy(buf, hva, len); + + return 0; +} + +static int kvmgt_read_gpa(unsigned long handle, unsigned long gpa, + void *buf, unsigned long len) +{ + return kvmgt_rw_gpa(handle, gpa, buf, len, false); +} + +static int kvmgt_write_gpa(unsigned long handle, unsigned long gpa, + void *buf, unsigned long len) +{ + return kvmgt_rw_gpa(handle, gpa, buf, len, true); +} + +static unsigned long kvmgt_virt_to_pfn(void *addr) +{ + return PFN_DOWN(__pa(addr)); +} + +struct intel_gvt_mpt kvmgt_mpt = { + .detect_host = kvmgt_detect_host, + .host_init = kvmgt_host_init, + .host_exit = kvmgt_host_exit, + .attach_vgpu = kvmgt_attach_vgpu, + .detach_vgpu = kvmgt_detach_vgpu, + .inject_msi = kvmgt_inject_msi, + .from_virt_to_mfn = kvmgt_virt_to_pfn, + .set_wp_page = kvmgt_write_protect_add, + .unset_wp_page = kvmgt_write_protect_remove, + .read_gpa = kvmgt_read_gpa, + .write_gpa = kvmgt_write_gpa, + .gfn_to_mfn = kvmgt_gfn_to_pfn, +}; +EXPORT_SYMBOL_GPL(kvmgt_mpt); + +static int __init kvmgt_init(void) +{ + return 0; +} + +static void __exit kvmgt_exit(void) +{ +} + +module_init(kvmgt_init); +module_exit(kvmgt_exit); + +MODULE_LICENSE("GPL and additional rights"); +MODULE_AUTHOR("Intel Corporation"); |