diff options
Diffstat (limited to 'virt')
| -rw-r--r-- | virt/kvm/Kconfig | 6 | ||||
| -rw-r--r-- | virt/kvm/dirty_ring.c | 46 | ||||
| -rw-r--r-- | virt/kvm/irqchip.c | 3 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 159 | ||||
| -rw-r--r-- | virt/kvm/kvm_mm.h | 4 | ||||
| -rw-r--r-- | virt/kvm/pfncache.c | 121 |
6 files changed, 236 insertions, 103 deletions
diff --git a/virt/kvm/Kconfig b/virt/kvm/Kconfig index 800f9470e36b..9fb1ff6f19e5 100644 --- a/virt/kvm/Kconfig +++ b/virt/kvm/Kconfig @@ -33,6 +33,12 @@ config HAVE_KVM_DIRTY_RING_ACQ_REL bool select HAVE_KVM_DIRTY_RING +# Allow enabling both the dirty bitmap and dirty ring. Only architectures +# that need to dirty memory outside of a vCPU context should select this. +config NEED_KVM_DIRTY_RING_WITH_BITMAP + bool + depends on HAVE_KVM_DIRTY_RING + config HAVE_KVM_EVENTFD bool select EVENTFD diff --git a/virt/kvm/dirty_ring.c b/virt/kvm/dirty_ring.c index d6fabf238032..c1cd7dfe4a90 100644 --- a/virt/kvm/dirty_ring.c +++ b/virt/kvm/dirty_ring.c @@ -21,12 +21,26 @@ u32 kvm_dirty_ring_get_rsvd_entries(void) return KVM_DIRTY_RING_RSVD_ENTRIES + kvm_cpu_dirty_log_size(); } +bool kvm_use_dirty_bitmap(struct kvm *kvm) +{ + lockdep_assert_held(&kvm->slots_lock); + + return !kvm->dirty_ring_size || kvm->dirty_ring_with_bitmap; +} + +#ifndef CONFIG_NEED_KVM_DIRTY_RING_WITH_BITMAP +bool kvm_arch_allow_write_without_running_vcpu(struct kvm *kvm) +{ + return false; +} +#endif + static u32 kvm_dirty_ring_used(struct kvm_dirty_ring *ring) { return READ_ONCE(ring->dirty_index) - READ_ONCE(ring->reset_index); } -bool kvm_dirty_ring_soft_full(struct kvm_dirty_ring *ring) +static bool kvm_dirty_ring_soft_full(struct kvm_dirty_ring *ring) { return kvm_dirty_ring_used(ring) >= ring->soft_limit; } @@ -142,13 +156,19 @@ int kvm_dirty_ring_reset(struct kvm *kvm, struct kvm_dirty_ring *ring) kvm_reset_dirty_gfn(kvm, cur_slot, cur_offset, mask); + /* + * The request KVM_REQ_DIRTY_RING_SOFT_FULL will be cleared + * by the VCPU thread next time when it enters the guest. + */ + trace_kvm_dirty_ring_reset(ring); return count; } -void kvm_dirty_ring_push(struct kvm_dirty_ring *ring, u32 slot, u64 offset) +void kvm_dirty_ring_push(struct kvm_vcpu *vcpu, u32 slot, u64 offset) { + struct kvm_dirty_ring *ring = &vcpu->dirty_ring; struct kvm_dirty_gfn *entry; /* It should never get full */ @@ -166,6 +186,28 @@ void kvm_dirty_ring_push(struct kvm_dirty_ring *ring, u32 slot, u64 offset) kvm_dirty_gfn_set_dirtied(entry); ring->dirty_index++; trace_kvm_dirty_ring_push(ring, slot, offset); + + if (kvm_dirty_ring_soft_full(ring)) + kvm_make_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu); +} + +bool kvm_dirty_ring_check_request(struct kvm_vcpu *vcpu) +{ + /* + * The VCPU isn't runnable when the dirty ring becomes soft full. + * The KVM_REQ_DIRTY_RING_SOFT_FULL event is always set to prevent + * the VCPU from running until the dirty pages are harvested and + * the dirty ring is reset by userspace. + */ + if (kvm_check_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu) && + kvm_dirty_ring_soft_full(&vcpu->dirty_ring)) { + kvm_make_request(KVM_REQ_DIRTY_RING_SOFT_FULL, vcpu); + vcpu->run->exit_reason = KVM_EXIT_DIRTY_RING_FULL; + trace_kvm_dirty_ring_exit(vcpu); + return true; + } + + return false; } struct page *kvm_dirty_ring_get_page(struct kvm_dirty_ring *ring, u32 offset) diff --git a/virt/kvm/irqchip.c b/virt/kvm/irqchip.c index 58e4f88b2b9f..1e567d1f6d3d 100644 --- a/virt/kvm/irqchip.c +++ b/virt/kvm/irqchip.c @@ -17,7 +17,6 @@ #include <linux/srcu.h> #include <linux/export.h> #include <trace/events/kvm.h> -#include "irq.h" int kvm_irq_map_gsi(struct kvm *kvm, struct kvm_kernel_irq_routing_entry *entries, int gsi) @@ -50,7 +49,7 @@ int kvm_send_userspace_msi(struct kvm *kvm, struct kvm_msi *msi) { struct kvm_kernel_irq_routing_entry route; - if (!irqchip_in_kernel(kvm) || (msi->flags & ~KVM_MSI_VALID_DEVID)) + if (!kvm_arch_irqchip_in_kernel(kvm) || (msi->flags & ~KVM_MSI_VALID_DEVID)) return -EINVAL; route.msi.address_lo = msi->address_lo; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 25d7872b29c1..13e88297f999 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1198,8 +1198,6 @@ static struct kvm *kvm_create_vm(unsigned long type, const char *fdname) goto out_err_no_arch_destroy_vm; } - kvm->max_halt_poll_ns = halt_poll_ns; - r = kvm_arch_init_vm(kvm, type); if (r) goto out_err_no_arch_destroy_vm; @@ -1617,7 +1615,7 @@ static int kvm_prepare_memory_region(struct kvm *kvm, new->dirty_bitmap = NULL; else if (old && old->dirty_bitmap) new->dirty_bitmap = old->dirty_bitmap; - else if (!kvm->dirty_ring_size) { + else if (kvm_use_dirty_bitmap(kvm)) { r = kvm_alloc_dirty_bitmap(new); if (r) return r; @@ -1641,6 +1639,8 @@ static void kvm_commit_memory_region(struct kvm *kvm, const struct kvm_memory_slot *new, enum kvm_mr_change change) { + int old_flags = old ? old->flags : 0; + int new_flags = new ? new->flags : 0; /* * Update the total number of memslot pages before calling the arch * hook so that architectures can consume the result directly. @@ -1650,6 +1650,12 @@ static void kvm_commit_memory_region(struct kvm *kvm, else if (change == KVM_MR_CREATE) kvm->nr_memslot_pages += new->npages; + if ((old_flags ^ new_flags) & KVM_MEM_LOG_DIRTY_PAGES) { + int change = (new_flags & KVM_MEM_LOG_DIRTY_PAGES) ? 1 : -1; + atomic_set(&kvm->nr_memslots_dirty_logging, + atomic_read(&kvm->nr_memslots_dirty_logging) + change); + } + kvm_arch_commit_memory_region(kvm, old, new, change); switch (change) { @@ -2060,8 +2066,8 @@ int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log, unsigned long n; unsigned long any = 0; - /* Dirty ring tracking is exclusive to dirty log tracking */ - if (kvm->dirty_ring_size) + /* Dirty ring tracking may be exclusive to dirty log tracking */ + if (!kvm_use_dirty_bitmap(kvm)) return -ENXIO; *memslot = NULL; @@ -2125,8 +2131,8 @@ static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log) unsigned long *dirty_bitmap_buffer; bool flush; - /* Dirty ring tracking is exclusive to dirty log tracking */ - if (kvm->dirty_ring_size) + /* Dirty ring tracking may be exclusive to dirty log tracking */ + if (!kvm_use_dirty_bitmap(kvm)) return -ENXIO; as_id = log->slot >> 16; @@ -2237,8 +2243,8 @@ static int kvm_clear_dirty_log_protect(struct kvm *kvm, unsigned long *dirty_bitmap_buffer; bool flush; - /* Dirty ring tracking is exclusive to dirty log tracking */ - if (kvm->dirty_ring_size) + /* Dirty ring tracking may be exclusive to dirty log tracking */ + if (!kvm_use_dirty_bitmap(kvm)) return -ENXIO; as_id = log->slot >> 16; @@ -2514,7 +2520,7 @@ static bool hva_to_pfn_fast(unsigned long addr, bool write_fault, * 1 indicates success, -errno is returned if error is detected. */ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, - bool *writable, kvm_pfn_t *pfn) + bool interruptible, bool *writable, kvm_pfn_t *pfn) { unsigned int flags = FOLL_HWPOISON; struct page *page; @@ -2529,6 +2535,8 @@ static int hva_to_pfn_slow(unsigned long addr, bool *async, bool write_fault, flags |= FOLL_WRITE; if (async) flags |= FOLL_NOWAIT; + if (interruptible) + flags |= FOLL_INTERRUPTIBLE; npages = get_user_pages_unlocked(addr, 1, &page, flags); if (npages != 1) @@ -2638,6 +2646,7 @@ out: * Pin guest page in memory and return its pfn. * @addr: host virtual address which maps memory to the guest * @atomic: whether this function can sleep + * @interruptible: whether the process can be interrupted by non-fatal signals * @async: whether this function need to wait IO complete if the * host page is not in the memory * @write_fault: whether we should get a writable host page @@ -2648,8 +2657,8 @@ out: * 2): @write_fault = false && @writable, @writable will tell the caller * whether the mapping is writable. */ -kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, - bool write_fault, bool *writable) +kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool interruptible, + bool *async, bool write_fault, bool *writable) { struct vm_area_struct *vma; kvm_pfn_t pfn; @@ -2664,9 +2673,12 @@ kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, if (atomic) return KVM_PFN_ERR_FAULT; - npages = hva_to_pfn_slow(addr, async, write_fault, writable, &pfn); + npages = hva_to_pfn_slow(addr, async, write_fault, interruptible, + writable, &pfn); if (npages == 1) return pfn; + if (npages == -EINTR) + return KVM_PFN_ERR_SIGPENDING; mmap_read_lock(current->mm); if (npages == -EHWPOISON || @@ -2697,8 +2709,8 @@ exit: } kvm_pfn_t __gfn_to_pfn_memslot(const struct kvm_memory_slot *slot, gfn_t gfn, - bool atomic, bool *async, bool write_fault, - bool *writable, hva_t *hva) + bool atomic, bool interruptible, bool *async, + bool write_fault, bool *writable, hva_t *hva) { unsigned long addr = __gfn_to_hva_many(slot, gfn, NULL, write_fault); @@ -2723,7 +2735,7 @@ kvm_pfn_t __gfn_to_pfn_memslot(const struct kvm_memory_slot *slot, gfn_t gfn, writable = NULL; } - return hva_to_pfn(addr, atomic, async, write_fault, + return hva_to_pfn(addr, atomic, interruptible, async, write_fault, writable); } EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot); @@ -2731,20 +2743,22 @@ EXPORT_SYMBOL_GPL(__gfn_to_pfn_memslot); kvm_pfn_t gfn_to_pfn_prot(struct kvm *kvm, gfn_t gfn, bool write_fault, bool *writable) { - return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, NULL, - write_fault, writable, NULL); + return __gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn, false, false, + NULL, write_fault, writable, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_prot); kvm_pfn_t gfn_to_pfn_memslot(const struct kvm_memory_slot *slot, gfn_t gfn) { - return __gfn_to_pfn_memslot(slot, gfn, false, NULL, true, NULL, NULL); + return __gfn_to_pfn_memslot(slot, gfn, false, false, NULL, true, + NULL, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot); kvm_pfn_t gfn_to_pfn_memslot_atomic(const struct kvm_memory_slot *slot, gfn_t gfn) { - return __gfn_to_pfn_memslot(slot, gfn, true, NULL, true, NULL, NULL); + return __gfn_to_pfn_memslot(slot, gfn, true, false, NULL, true, + NULL, NULL); } EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic); @@ -3305,18 +3319,19 @@ void mark_page_dirty_in_slot(struct kvm *kvm, struct kvm_vcpu *vcpu = kvm_get_running_vcpu(); #ifdef CONFIG_HAVE_KVM_DIRTY_RING - if (WARN_ON_ONCE(!vcpu) || WARN_ON_ONCE(vcpu->kvm != kvm)) + if (WARN_ON_ONCE(vcpu && vcpu->kvm != kvm)) return; + + WARN_ON_ONCE(!vcpu && !kvm_arch_allow_write_without_running_vcpu(kvm)); #endif if (memslot && kvm_slot_dirty_track_enabled(memslot)) { unsigned long rel_gfn = gfn - memslot->base_gfn; u32 slot = (memslot->as_id << 16) | memslot->id; - if (kvm->dirty_ring_size) - kvm_dirty_ring_push(&vcpu->dirty_ring, - slot, rel_gfn); - else + if (kvm->dirty_ring_size && vcpu) + kvm_dirty_ring_push(vcpu, slot, rel_gfn); + else if (memslot->dirty_bitmap) set_bit_le(rel_gfn, memslot->dirty_bitmap); } } @@ -3377,9 +3392,6 @@ static void grow_halt_poll_ns(struct kvm_vcpu *vcpu) if (val < grow_start) val = grow_start; - if (val > vcpu->kvm->max_halt_poll_ns) - val = vcpu->kvm->max_halt_poll_ns; - vcpu->halt_poll_ns = val; out: trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old); @@ -3483,6 +3495,24 @@ static inline void update_halt_poll_stats(struct kvm_vcpu *vcpu, ktime_t start, } } +static unsigned int kvm_vcpu_max_halt_poll_ns(struct kvm_vcpu *vcpu) +{ + struct kvm *kvm = vcpu->kvm; + + if (kvm->override_halt_poll_ns) { + /* + * Ensure kvm->max_halt_poll_ns is not read before + * kvm->override_halt_poll_ns. + * + * Pairs with the smp_wmb() when enabling KVM_CAP_HALT_POLL. + */ + smp_rmb(); + return READ_ONCE(kvm->max_halt_poll_ns); + } + + return READ_ONCE(halt_poll_ns); +} + /* * Emulate a vCPU halt condition, e.g. HLT on x86, WFI on arm, etc... If halt * polling is enabled, busy wait for a short time before blocking to avoid the @@ -3491,21 +3521,23 @@ static inline void update_halt_poll_stats(struct kvm_vcpu *vcpu, ktime_t start, */ void kvm_vcpu_halt(struct kvm_vcpu *vcpu) { + unsigned int max_halt_poll_ns = kvm_vcpu_max_halt_poll_ns(vcpu); bool halt_poll_allowed = !kvm_arch_no_poll(vcpu); - bool do_halt_poll = halt_poll_allowed && vcpu->halt_poll_ns; ktime_t start, cur, poll_end; bool waited = false; + bool do_halt_poll; u64 halt_ns; + if (vcpu->halt_poll_ns > max_halt_poll_ns) + vcpu->halt_poll_ns = max_halt_poll_ns; + + do_halt_poll = halt_poll_allowed && vcpu->halt_poll_ns; + start = cur = poll_end = ktime_get(); if (do_halt_poll) { ktime_t stop = ktime_add_ns(start, vcpu->halt_poll_ns); do { - /* - * This sets KVM_REQ_UNHALT if an interrupt - * arrives. - */ if (kvm_vcpu_check_block(vcpu) < 0) goto out; cpu_relax(); @@ -3535,18 +3567,21 @@ out: update_halt_poll_stats(vcpu, start, poll_end, !waited); if (halt_poll_allowed) { + /* Recompute the max halt poll time in case it changed. */ + max_halt_poll_ns = kvm_vcpu_max_halt_poll_ns(vcpu); + if (!vcpu_valid_wakeup(vcpu)) { shrink_halt_poll_ns(vcpu); - } else if (vcpu->kvm->max_halt_poll_ns) { + } else if (max_halt_poll_ns) { if (halt_ns <= vcpu->halt_poll_ns) ; /* we had a long block, shrink polling */ else if (vcpu->halt_poll_ns && - halt_ns > vcpu->kvm->max_halt_poll_ns) + halt_ns > max_halt_poll_ns) shrink_halt_poll_ns(vcpu); /* we had a short halt and our poll time is too small */ - else if (vcpu->halt_poll_ns < vcpu->kvm->max_halt_poll_ns && - halt_ns < vcpu->kvm->max_halt_poll_ns) + else if (vcpu->halt_poll_ns < max_halt_poll_ns && + halt_ns < max_halt_poll_ns) grow_halt_poll_ns(vcpu); } else { vcpu->halt_poll_ns = 0; @@ -4484,6 +4519,9 @@ static long kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg) #else return 0; #endif +#ifdef CONFIG_NEED_KVM_DIRTY_RING_WITH_BITMAP + case KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP: +#endif case KVM_CAP_BINARY_STATS_FD: case KVM_CAP_SYSTEM_EVENT_DATA: return 1; @@ -4559,6 +4597,20 @@ int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm, return -EINVAL; } +static bool kvm_are_all_memslots_empty(struct kvm *kvm) +{ + int i; + + lockdep_assert_held(&kvm->slots_lock); + + for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) { + if (!kvm_memslots_empty(__kvm_memslots(kvm, i))) + return false; + } + + return true; +} + static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm, struct kvm_enable_cap *cap) { @@ -4581,6 +4633,16 @@ static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm, return -EINVAL; kvm->max_halt_poll_ns = cap->args[0]; + + /* + * Ensure kvm->override_halt_poll_ns does not become visible + * before kvm->max_halt_poll_ns. + * + * Pairs with the smp_rmb() in kvm_vcpu_max_halt_poll_ns(). + */ + smp_wmb(); + kvm->override_halt_poll_ns = true; + return 0; } case KVM_CAP_DIRTY_LOG_RING: @@ -4589,6 +4651,29 @@ static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm, return -EINVAL; return kvm_vm_ioctl_enable_dirty_log_ring(kvm, cap->args[0]); + case KVM_CAP_DIRTY_LOG_RING_WITH_BITMAP: { + int r = -EINVAL; + + if (!IS_ENABLED(CONFIG_NEED_KVM_DIRTY_RING_WITH_BITMAP) || + !kvm->dirty_ring_size || cap->flags) + return r; + + mutex_lock(&kvm->slots_lock); + + /* + * For simplicity, allow enabling ring+bitmap if and only if + * there are no memslots, e.g. to ensure all memslots allocate + * a bitmap after the capability is enabled. + */ + if (kvm_are_all_memslots_empty(kvm)) { + kvm->dirty_ring_with_bitmap = true; + r = 0; + } + + mutex_unlock(&kvm->slots_lock); + + return r; + } default: return kvm_vm_ioctl_enable_cap(kvm, cap); } diff --git a/virt/kvm/kvm_mm.h b/virt/kvm/kvm_mm.h index 41da467d99c9..a1ab15006af3 100644 --- a/virt/kvm/kvm_mm.h +++ b/virt/kvm/kvm_mm.h @@ -24,8 +24,8 @@ #define KVM_MMU_READ_UNLOCK(kvm) spin_unlock(&(kvm)->mmu_lock) #endif /* KVM_HAVE_MMU_RWLOCK */ -kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool *async, - bool write_fault, bool *writable); +kvm_pfn_t hva_to_pfn(unsigned long addr, bool atomic, bool interruptible, + bool *async, bool write_fault, bool *writable); #ifdef CONFIG_HAVE_KVM_PFNCACHE void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm, diff --git a/virt/kvm/pfncache.c b/virt/kvm/pfncache.c index 346e47f15572..2d6aba677830 100644 --- a/virt/kvm/pfncache.c +++ b/virt/kvm/pfncache.c @@ -76,19 +76,17 @@ void gfn_to_pfn_cache_invalidate_start(struct kvm *kvm, unsigned long start, } } -bool kvm_gfn_to_pfn_cache_check(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, - gpa_t gpa, unsigned long len) +bool kvm_gpc_check(struct gfn_to_pfn_cache *gpc, unsigned long len) { - struct kvm_memslots *slots = kvm_memslots(kvm); + struct kvm_memslots *slots = kvm_memslots(gpc->kvm); if (!gpc->active) return false; - if ((gpa & ~PAGE_MASK) + len > PAGE_SIZE) + if ((gpc->gpa & ~PAGE_MASK) + len > PAGE_SIZE) return false; - if (gpc->gpa != gpa || gpc->generation != slots->generation || - kvm_is_error_hva(gpc->uhva)) + if (gpc->generation != slots->generation || kvm_is_error_hva(gpc->uhva)) return false; if (!gpc->valid) @@ -96,9 +94,9 @@ bool kvm_gfn_to_pfn_cache_check(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, return true; } -EXPORT_SYMBOL_GPL(kvm_gfn_to_pfn_cache_check); +EXPORT_SYMBOL_GPL(kvm_gpc_check); -static void gpc_unmap_khva(struct kvm *kvm, kvm_pfn_t pfn, void *khva) +static void gpc_unmap_khva(kvm_pfn_t pfn, void *khva) { /* Unmap the old pfn/page if it was mapped before. */ if (!is_error_noslot_pfn(pfn) && khva) { @@ -139,7 +137,7 @@ static inline bool mmu_notifier_retry_cache(struct kvm *kvm, unsigned long mmu_s return kvm->mmu_invalidate_seq != mmu_seq; } -static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) +static kvm_pfn_t hva_to_pfn_retry(struct gfn_to_pfn_cache *gpc) { /* Note, the new page offset may be different than the old! */ void *old_khva = gpc->khva - offset_in_page(gpc->khva); @@ -159,7 +157,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) gpc->valid = false; do { - mmu_seq = kvm->mmu_invalidate_seq; + mmu_seq = gpc->kvm->mmu_invalidate_seq; smp_rmb(); write_unlock_irq(&gpc->lock); @@ -177,7 +175,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) * the existing mapping and didn't create a new one. */ if (new_khva != old_khva) - gpc_unmap_khva(kvm, new_pfn, new_khva); + gpc_unmap_khva(new_pfn, new_khva); kvm_release_pfn_clean(new_pfn); @@ -185,7 +183,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) } /* We always request a writeable mapping */ - new_pfn = hva_to_pfn(gpc->uhva, false, NULL, true, NULL); + new_pfn = hva_to_pfn(gpc->uhva, false, false, NULL, true, NULL); if (is_error_noslot_pfn(new_pfn)) goto out_error; @@ -217,7 +215,7 @@ static kvm_pfn_t hva_to_pfn_retry(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) * attempting to refresh. */ WARN_ON_ONCE(gpc->valid); - } while (mmu_notifier_retry_cache(kvm, mmu_seq)); + } while (mmu_notifier_retry_cache(gpc->kvm, mmu_seq)); gpc->valid = true; gpc->pfn = new_pfn; @@ -238,10 +236,10 @@ out_error: return -EFAULT; } -int kvm_gfn_to_pfn_cache_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, - gpa_t gpa, unsigned long len) +static int __kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, gpa_t gpa, + unsigned long len) { - struct kvm_memslots *slots = kvm_memslots(kvm); + struct kvm_memslots *slots = kvm_memslots(gpc->kvm); unsigned long page_offset = gpa & ~PAGE_MASK; bool unmap_old = false; unsigned long old_uhva; @@ -295,12 +293,16 @@ int kvm_gfn_to_pfn_cache_refresh(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, * drop the lock and do the HVA to PFN lookup again. */ if (!gpc->valid || old_uhva != gpc->uhva) { - ret = hva_to_pfn_retry(kvm, gpc); + ret = hva_to_pfn_retry(gpc); } else { - /* If the HVA→PFN mapping was already valid, don't unmap it. */ - old_pfn = KVM_PFN_ERR_FAULT; - old_khva = NULL; + /* + * If the HVA→PFN mapping was already valid, don't unmap it. + * But do update gpc->khva because the offset within the page + * may have changed. + */ + gpc->khva = old_khva + page_offset; ret = 0; + goto out_unlock; } out: @@ -324,59 +326,41 @@ out_unlock: mutex_unlock(&gpc->refresh_lock); if (unmap_old) - gpc_unmap_khva(kvm, old_pfn, old_khva); + gpc_unmap_khva(old_pfn, old_khva); return ret; } -EXPORT_SYMBOL_GPL(kvm_gfn_to_pfn_cache_refresh); -void kvm_gfn_to_pfn_cache_unmap(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) +int kvm_gpc_refresh(struct gfn_to_pfn_cache *gpc, unsigned long len) { - void *old_khva; - kvm_pfn_t old_pfn; - - mutex_lock(&gpc->refresh_lock); - write_lock_irq(&gpc->lock); - - gpc->valid = false; - - old_khva = gpc->khva - offset_in_page(gpc->khva); - old_pfn = gpc->pfn; - - /* - * We can leave the GPA → uHVA map cache intact but the PFN - * lookup will need to be redone even for the same page. - */ - gpc->khva = NULL; - gpc->pfn = KVM_PFN_ERR_FAULT; - - write_unlock_irq(&gpc->lock); - mutex_unlock(&gpc->refresh_lock); - - gpc_unmap_khva(kvm, old_pfn, old_khva); + return __kvm_gpc_refresh(gpc, gpc->gpa, len); } -EXPORT_SYMBOL_GPL(kvm_gfn_to_pfn_cache_unmap); +EXPORT_SYMBOL_GPL(kvm_gpc_refresh); -void kvm_gpc_init(struct gfn_to_pfn_cache *gpc) +void kvm_gpc_init(struct gfn_to_pfn_cache *gpc, struct kvm *kvm, + struct kvm_vcpu *vcpu, enum pfn_cache_usage usage) { + WARN_ON_ONCE(!usage || (usage & KVM_GUEST_AND_HOST_USE_PFN) != usage); + WARN_ON_ONCE((usage & KVM_GUEST_USES_PFN) && !vcpu); + rwlock_init(&gpc->lock); mutex_init(&gpc->refresh_lock); + + gpc->kvm = kvm; + gpc->vcpu = vcpu; + gpc->usage = usage; + gpc->pfn = KVM_PFN_ERR_FAULT; + gpc->uhva = KVM_HVA_ERR_BAD; } EXPORT_SYMBOL_GPL(kvm_gpc_init); -int kvm_gpc_activate(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, - struct kvm_vcpu *vcpu, enum pfn_cache_usage usage, - gpa_t gpa, unsigned long len) +int kvm_gpc_activate(struct gfn_to_pfn_cache *gpc, gpa_t gpa, unsigned long len) { - WARN_ON_ONCE(!usage || (usage & KVM_GUEST_AND_HOST_USE_PFN) != usage); + struct kvm *kvm = gpc->kvm; if (!gpc->active) { - gpc->khva = NULL; - gpc->pfn = KVM_PFN_ERR_FAULT; - gpc->uhva = KVM_HVA_ERR_BAD; - gpc->vcpu = vcpu; - gpc->usage = usage; - gpc->valid = false; + if (KVM_BUG_ON(gpc->valid, kvm)) + return -EIO; spin_lock(&kvm->gpc_lock); list_add(&gpc->list, &kvm->gpc_list); @@ -391,12 +375,16 @@ int kvm_gpc_activate(struct kvm *kvm, struct gfn_to_pfn_cache *gpc, gpc->active = true; write_unlock_irq(&gpc->lock); } - return kvm_gfn_to_pfn_cache_refresh(kvm, gpc, gpa, len); + return __kvm_gpc_refresh(gpc, gpa, len); } EXPORT_SYMBOL_GPL(kvm_gpc_activate); -void kvm_gpc_deactivate(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) +void kvm_gpc_deactivate(struct gfn_to_pfn_cache *gpc) { + struct kvm *kvm = gpc->kvm; + kvm_pfn_t old_pfn; + void *old_khva; + if (gpc->active) { /* * Deactivate the cache before removing it from the list, KVM @@ -405,13 +393,26 @@ void kvm_gpc_deactivate(struct kvm *kvm, struct gfn_to_pfn_cache *gpc) */ write_lock_irq(&gpc->lock); gpc->active = false; + gpc->valid = false; + + /* + * Leave the GPA => uHVA cache intact, it's protected by the + * memslot generation. The PFN lookup needs to be redone every + * time as mmu_notifier protection is lost when the cache is + * removed from the VM's gpc_list. + */ + old_khva = gpc->khva - offset_in_page(gpc->khva); + gpc->khva = NULL; + + old_pfn = gpc->pfn; + gpc->pfn = KVM_PFN_ERR_FAULT; write_unlock_irq(&gpc->lock); spin_lock(&kvm->gpc_lock); list_del(&gpc->list); spin_unlock(&kvm->gpc_lock); - kvm_gfn_to_pfn_cache_unmap(kvm, gpc); + gpc_unmap_khva(old_pfn, old_khva); } } EXPORT_SYMBOL_GPL(kvm_gpc_deactivate); |