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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-22 00:40:03 +00:00
![Linus Torvalds](/assets/img/avatar_default.png)
* Eager page splitting optimization for dirty logging, optionally allowing for a VM to avoid the cost of hugepage splitting in the stage-2 fault path. * Arm FF-A proxy for pKVM, allowing a pKVM host to safely interact with services that live in the Secure world. pKVM intervenes on FF-A calls to guarantee the host doesn't misuse memory donated to the hyp or a pKVM guest. * Support for running the split hypervisor with VHE enabled, known as 'hVHE' mode. This is extremely useful for testing the split hypervisor on VHE-only systems, and paves the way for new use cases that depend on having two TTBRs available at EL2. * Generalized framework for configurable ID registers from userspace. KVM/arm64 currently prevents arbitrary CPU feature set configuration from userspace, but the intent is to relax this limitation and allow userspace to select a feature set consistent with the CPU. * Enable the use of Branch Target Identification (FEAT_BTI) in the hypervisor. * Use a separate set of pointer authentication keys for the hypervisor when running in protected mode, as the host is untrusted at runtime. * Ensure timer IRQs are consistently released in the init failure paths. * Avoid trapping CTR_EL0 on systems with Enhanced Virtualization Traps (FEAT_EVT), as it is a register commonly read from userspace. * Erratum workaround for the upcoming AmpereOne part, which has broken hardware A/D state management. RISC-V: * Redirect AMO load/store misaligned traps to KVM guest * Trap-n-emulate AIA in-kernel irqchip for KVM guest * Svnapot support for KVM Guest s390: * New uvdevice secret API * CMM selftest and fixes * fix racy access to target CPU for diag 9c x86: * Fix missing/incorrect #GP checks on ENCLS * Use standard mmu_notifier hooks for handling APIC access page * Drop now unnecessary TR/TSS load after VM-Exit on AMD * Print more descriptive information about the status of SEV and SEV-ES during module load * Add a test for splitting and reconstituting hugepages during and after dirty logging * Add support for CPU pinning in demand paging test * Add support for AMD PerfMonV2, with a variety of cleanups and minor fixes included along the way * Add a "nx_huge_pages=never" option to effectively avoid creating NX hugepage recovery threads (because nx_huge_pages=off can be toggled at runtime) * Move handling of PAT out of MTRR code and dedup SVM+VMX code * Fix output of PIC poll command emulation when there's an interrupt * Add a maintainer's handbook to document KVM x86 processes, preferred coding style, testing expectations, etc. * Misc cleanups, fixes and comments Generic: * Miscellaneous bugfixes and cleanups Selftests: * Generate dependency files so that partial rebuilds work as expected -----BEGIN PGP SIGNATURE----- iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAmSgHrIUHHBib256aW5p QHJlZGhhdC5jb20ACgkQv/vSX3jHroORcAf+KkBlXwQMf+Q0Hy6Mfe0OtkKmh0Ae 6HJ6dsuMfOHhWv5kgukh+qvuGUGzHq+gpVKmZg2yP3h3cLHOLUAYMCDm+rjXyjsk F4DbnJLfxq43Pe9PHRKFxxSecRcRYCNox0GD5UYL4PLKcH0FyfQrV+HVBK+GI8L3 FDzUcyJkR12Lcj1qf++7fsbzfOshL0AJPmidQCoc6wkLJpUEr/nYUqlI1Kx3YNuQ LKmxFHS4l4/O/px3GKNDrLWDbrVlwciGIa3GZLS52PZdW3mAqT+cqcPcYK6SW71P m1vE80VbNELX5q3YSRoOXtedoZ3Pk97LEmz/xQAsJ/jri0Z5Syk0Ok0m/Q== =AMXp -----END PGP SIGNATURE----- Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm Pull kvm updates from Paolo Bonzini: "ARM64: - Eager page splitting optimization for dirty logging, optionally allowing for a VM to avoid the cost of hugepage splitting in the stage-2 fault path. - Arm FF-A proxy for pKVM, allowing a pKVM host to safely interact with services that live in the Secure world. pKVM intervenes on FF-A calls to guarantee the host doesn't misuse memory donated to the hyp or a pKVM guest. - Support for running the split hypervisor with VHE enabled, known as 'hVHE' mode. This is extremely useful for testing the split hypervisor on VHE-only systems, and paves the way for new use cases that depend on having two TTBRs available at EL2. - Generalized framework for configurable ID registers from userspace. KVM/arm64 currently prevents arbitrary CPU feature set configuration from userspace, but the intent is to relax this limitation and allow userspace to select a feature set consistent with the CPU. - Enable the use of Branch Target Identification (FEAT_BTI) in the hypervisor. - Use a separate set of pointer authentication keys for the hypervisor when running in protected mode, as the host is untrusted at runtime. - Ensure timer IRQs are consistently released in the init failure paths. - Avoid trapping CTR_EL0 on systems with Enhanced Virtualization Traps (FEAT_EVT), as it is a register commonly read from userspace. - Erratum workaround for the upcoming AmpereOne part, which has broken hardware A/D state management. RISC-V: - Redirect AMO load/store misaligned traps to KVM guest - Trap-n-emulate AIA in-kernel irqchip for KVM guest - Svnapot support for KVM Guest s390: - New uvdevice secret API - CMM selftest and fixes - fix racy access to target CPU for diag 9c x86: - Fix missing/incorrect #GP checks on ENCLS - Use standard mmu_notifier hooks for handling APIC access page - Drop now unnecessary TR/TSS load after VM-Exit on AMD - Print more descriptive information about the status of SEV and SEV-ES during module load - Add a test for splitting and reconstituting hugepages during and after dirty logging - Add support for CPU pinning in demand paging test - Add support for AMD PerfMonV2, with a variety of cleanups and minor fixes included along the way - Add a "nx_huge_pages=never" option to effectively avoid creating NX hugepage recovery threads (because nx_huge_pages=off can be toggled at runtime) - Move handling of PAT out of MTRR code and dedup SVM+VMX code - Fix output of PIC poll command emulation when there's an interrupt - Add a maintainer's handbook to document KVM x86 processes, preferred coding style, testing expectations, etc. - Misc cleanups, fixes and comments Generic: - Miscellaneous bugfixes and cleanups Selftests: - Generate dependency files so that partial rebuilds work as expected" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (153 commits) Documentation/process: Add a maintainer handbook for KVM x86 Documentation/process: Add a label for the tip tree handbook's coding style KVM: arm64: Fix misuse of KVM_ARM_VCPU_POWER_OFF bit index RISC-V: KVM: Remove unneeded semicolon RISC-V: KVM: Allow Svnapot extension for Guest/VM riscv: kvm: define vcpu_sbi_ext_pmu in header RISC-V: KVM: Expose IMSIC registers as attributes of AIA irqchip RISC-V: KVM: Add in-kernel virtualization of AIA IMSIC RISC-V: KVM: Expose APLIC registers as attributes of AIA irqchip RISC-V: KVM: Add in-kernel emulation of AIA APLIC RISC-V: KVM: Implement device interface for AIA irqchip RISC-V: KVM: Skeletal in-kernel AIA irqchip support RISC-V: KVM: Set kvm_riscv_aia_nr_hgei to zero RISC-V: KVM: Add APLIC related defines RISC-V: KVM: Add IMSIC related defines RISC-V: KVM: Implement guest external interrupt line management KVM: x86: Remove PRIx* definitions as they are solely for user space s390/uv: Update query for secret-UVCs s390/uv: replace scnprintf with sysfs_emit s390/uvdevice: Add 'Lock Secret Store' UVC ...
6205 lines
154 KiB
C
6205 lines
154 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* Kernel-based Virtual Machine driver for Linux
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*
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* This module enables machines with Intel VT-x extensions to run virtual
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* machines without emulation or binary translation.
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*
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* Copyright (C) 2006 Qumranet, Inc.
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* Copyright 2010 Red Hat, Inc. and/or its affiliates.
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*
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* Authors:
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* Avi Kivity <avi@qumranet.com>
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* Yaniv Kamay <yaniv@qumranet.com>
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*/
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#include <kvm/iodev.h>
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#include <linux/kvm_host.h>
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#include <linux/kvm.h>
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#include <linux/module.h>
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#include <linux/errno.h>
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#include <linux/percpu.h>
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#include <linux/mm.h>
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#include <linux/miscdevice.h>
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#include <linux/vmalloc.h>
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#include <linux/reboot.h>
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#include <linux/debugfs.h>
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#include <linux/highmem.h>
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#include <linux/file.h>
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#include <linux/syscore_ops.h>
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#include <linux/cpu.h>
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#include <linux/sched/signal.h>
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#include <linux/sched/mm.h>
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#include <linux/sched/stat.h>
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#include <linux/cpumask.h>
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#include <linux/smp.h>
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#include <linux/anon_inodes.h>
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#include <linux/profile.h>
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#include <linux/kvm_para.h>
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#include <linux/pagemap.h>
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#include <linux/mman.h>
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#include <linux/swap.h>
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#include <linux/bitops.h>
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#include <linux/spinlock.h>
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#include <linux/compat.h>
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#include <linux/srcu.h>
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#include <linux/hugetlb.h>
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#include <linux/slab.h>
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#include <linux/sort.h>
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#include <linux/bsearch.h>
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#include <linux/io.h>
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#include <linux/lockdep.h>
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#include <linux/kthread.h>
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#include <linux/suspend.h>
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#include <asm/processor.h>
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#include <asm/ioctl.h>
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#include <linux/uaccess.h>
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#include "coalesced_mmio.h"
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#include "async_pf.h"
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#include "kvm_mm.h"
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#include "vfio.h"
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#include <trace/events/ipi.h>
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#define CREATE_TRACE_POINTS
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#include <trace/events/kvm.h>
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#include <linux/kvm_dirty_ring.h>
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/* Worst case buffer size needed for holding an integer. */
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#define ITOA_MAX_LEN 12
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MODULE_AUTHOR("Qumranet");
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MODULE_LICENSE("GPL");
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/* Architectures should define their poll value according to the halt latency */
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unsigned int halt_poll_ns = KVM_HALT_POLL_NS_DEFAULT;
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module_param(halt_poll_ns, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns);
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/* Default doubles per-vcpu halt_poll_ns. */
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unsigned int halt_poll_ns_grow = 2;
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module_param(halt_poll_ns_grow, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns_grow);
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/* The start value to grow halt_poll_ns from */
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unsigned int halt_poll_ns_grow_start = 10000; /* 10us */
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module_param(halt_poll_ns_grow_start, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns_grow_start);
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/* Default resets per-vcpu halt_poll_ns . */
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unsigned int halt_poll_ns_shrink;
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module_param(halt_poll_ns_shrink, uint, 0644);
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EXPORT_SYMBOL_GPL(halt_poll_ns_shrink);
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/*
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* Ordering of locks:
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*
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* kvm->lock --> kvm->slots_lock --> kvm->irq_lock
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*/
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DEFINE_MUTEX(kvm_lock);
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LIST_HEAD(vm_list);
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static struct kmem_cache *kvm_vcpu_cache;
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static __read_mostly struct preempt_ops kvm_preempt_ops;
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static DEFINE_PER_CPU(struct kvm_vcpu *, kvm_running_vcpu);
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struct dentry *kvm_debugfs_dir;
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EXPORT_SYMBOL_GPL(kvm_debugfs_dir);
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static const struct file_operations stat_fops_per_vm;
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static struct file_operations kvm_chardev_ops;
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static long kvm_vcpu_ioctl(struct file *file, unsigned int ioctl,
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unsigned long arg);
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#ifdef CONFIG_KVM_COMPAT
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static long kvm_vcpu_compat_ioctl(struct file *file, unsigned int ioctl,
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unsigned long arg);
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#define KVM_COMPAT(c) .compat_ioctl = (c)
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#else
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/*
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* For architectures that don't implement a compat infrastructure,
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* adopt a double line of defense:
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* - Prevent a compat task from opening /dev/kvm
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* - If the open has been done by a 64bit task, and the KVM fd
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* passed to a compat task, let the ioctls fail.
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*/
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static long kvm_no_compat_ioctl(struct file *file, unsigned int ioctl,
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unsigned long arg) { return -EINVAL; }
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static int kvm_no_compat_open(struct inode *inode, struct file *file)
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{
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return is_compat_task() ? -ENODEV : 0;
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}
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#define KVM_COMPAT(c) .compat_ioctl = kvm_no_compat_ioctl, \
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.open = kvm_no_compat_open
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#endif
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static int hardware_enable_all(void);
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static void hardware_disable_all(void);
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static void kvm_io_bus_destroy(struct kvm_io_bus *bus);
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#define KVM_EVENT_CREATE_VM 0
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#define KVM_EVENT_DESTROY_VM 1
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static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm);
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static unsigned long long kvm_createvm_count;
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static unsigned long long kvm_active_vms;
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static DEFINE_PER_CPU(cpumask_var_t, cpu_kick_mask);
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__weak void kvm_arch_guest_memory_reclaimed(struct kvm *kvm)
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{
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}
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bool kvm_is_zone_device_page(struct page *page)
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{
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/*
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* The metadata used by is_zone_device_page() to determine whether or
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* not a page is ZONE_DEVICE is guaranteed to be valid if and only if
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* the device has been pinned, e.g. by get_user_pages(). WARN if the
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* page_count() is zero to help detect bad usage of this helper.
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*/
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if (WARN_ON_ONCE(!page_count(page)))
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return false;
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return is_zone_device_page(page);
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}
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/*
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* Returns a 'struct page' if the pfn is "valid" and backed by a refcounted
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* page, NULL otherwise. Note, the list of refcounted PG_reserved page types
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* is likely incomplete, it has been compiled purely through people wanting to
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* back guest with a certain type of memory and encountering issues.
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*/
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struct page *kvm_pfn_to_refcounted_page(kvm_pfn_t pfn)
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{
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struct page *page;
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if (!pfn_valid(pfn))
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return NULL;
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page = pfn_to_page(pfn);
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if (!PageReserved(page))
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return page;
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/* The ZERO_PAGE(s) is marked PG_reserved, but is refcounted. */
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if (is_zero_pfn(pfn))
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return page;
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/*
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* ZONE_DEVICE pages currently set PG_reserved, but from a refcounting
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* perspective they are "normal" pages, albeit with slightly different
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* usage rules.
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*/
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if (kvm_is_zone_device_page(page))
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return page;
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return NULL;
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}
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/*
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* Switches to specified vcpu, until a matching vcpu_put()
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*/
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void vcpu_load(struct kvm_vcpu *vcpu)
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{
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int cpu = get_cpu();
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__this_cpu_write(kvm_running_vcpu, vcpu);
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preempt_notifier_register(&vcpu->preempt_notifier);
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kvm_arch_vcpu_load(vcpu, cpu);
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put_cpu();
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}
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EXPORT_SYMBOL_GPL(vcpu_load);
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void vcpu_put(struct kvm_vcpu *vcpu)
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{
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preempt_disable();
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kvm_arch_vcpu_put(vcpu);
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preempt_notifier_unregister(&vcpu->preempt_notifier);
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__this_cpu_write(kvm_running_vcpu, NULL);
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preempt_enable();
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}
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EXPORT_SYMBOL_GPL(vcpu_put);
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/* TODO: merge with kvm_arch_vcpu_should_kick */
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static bool kvm_request_needs_ipi(struct kvm_vcpu *vcpu, unsigned req)
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{
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int mode = kvm_vcpu_exiting_guest_mode(vcpu);
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/*
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* We need to wait for the VCPU to reenable interrupts and get out of
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* READING_SHADOW_PAGE_TABLES mode.
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*/
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if (req & KVM_REQUEST_WAIT)
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return mode != OUTSIDE_GUEST_MODE;
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/*
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* Need to kick a running VCPU, but otherwise there is nothing to do.
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*/
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return mode == IN_GUEST_MODE;
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}
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static void ack_kick(void *_completed)
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{
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}
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static inline bool kvm_kick_many_cpus(struct cpumask *cpus, bool wait)
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{
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if (cpumask_empty(cpus))
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return false;
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smp_call_function_many(cpus, ack_kick, NULL, wait);
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return true;
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}
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static void kvm_make_vcpu_request(struct kvm_vcpu *vcpu, unsigned int req,
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struct cpumask *tmp, int current_cpu)
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{
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int cpu;
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if (likely(!(req & KVM_REQUEST_NO_ACTION)))
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__kvm_make_request(req, vcpu);
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if (!(req & KVM_REQUEST_NO_WAKEUP) && kvm_vcpu_wake_up(vcpu))
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return;
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/*
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* Note, the vCPU could get migrated to a different pCPU at any point
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* after kvm_request_needs_ipi(), which could result in sending an IPI
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* to the previous pCPU. But, that's OK because the purpose of the IPI
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* is to ensure the vCPU returns to OUTSIDE_GUEST_MODE, which is
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* satisfied if the vCPU migrates. Entering READING_SHADOW_PAGE_TABLES
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* after this point is also OK, as the requirement is only that KVM wait
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* for vCPUs that were reading SPTEs _before_ any changes were
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* finalized. See kvm_vcpu_kick() for more details on handling requests.
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*/
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if (kvm_request_needs_ipi(vcpu, req)) {
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cpu = READ_ONCE(vcpu->cpu);
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if (cpu != -1 && cpu != current_cpu)
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__cpumask_set_cpu(cpu, tmp);
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}
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}
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bool kvm_make_vcpus_request_mask(struct kvm *kvm, unsigned int req,
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unsigned long *vcpu_bitmap)
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{
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struct kvm_vcpu *vcpu;
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struct cpumask *cpus;
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int i, me;
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bool called;
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me = get_cpu();
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cpus = this_cpu_cpumask_var_ptr(cpu_kick_mask);
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cpumask_clear(cpus);
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for_each_set_bit(i, vcpu_bitmap, KVM_MAX_VCPUS) {
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vcpu = kvm_get_vcpu(kvm, i);
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if (!vcpu)
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continue;
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kvm_make_vcpu_request(vcpu, req, cpus, me);
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}
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called = kvm_kick_many_cpus(cpus, !!(req & KVM_REQUEST_WAIT));
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put_cpu();
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return called;
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}
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bool kvm_make_all_cpus_request_except(struct kvm *kvm, unsigned int req,
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struct kvm_vcpu *except)
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{
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struct kvm_vcpu *vcpu;
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struct cpumask *cpus;
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unsigned long i;
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bool called;
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int me;
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me = get_cpu();
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cpus = this_cpu_cpumask_var_ptr(cpu_kick_mask);
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cpumask_clear(cpus);
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kvm_for_each_vcpu(i, vcpu, kvm) {
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if (vcpu == except)
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continue;
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kvm_make_vcpu_request(vcpu, req, cpus, me);
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}
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called = kvm_kick_many_cpus(cpus, !!(req & KVM_REQUEST_WAIT));
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put_cpu();
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return called;
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}
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bool kvm_make_all_cpus_request(struct kvm *kvm, unsigned int req)
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{
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return kvm_make_all_cpus_request_except(kvm, req, NULL);
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}
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EXPORT_SYMBOL_GPL(kvm_make_all_cpus_request);
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#ifndef CONFIG_HAVE_KVM_ARCH_TLB_FLUSH_ALL
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void kvm_flush_remote_tlbs(struct kvm *kvm)
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{
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++kvm->stat.generic.remote_tlb_flush_requests;
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/*
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* We want to publish modifications to the page tables before reading
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* mode. Pairs with a memory barrier in arch-specific code.
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* - x86: smp_mb__after_srcu_read_unlock in vcpu_enter_guest
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* and smp_mb in walk_shadow_page_lockless_begin/end.
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* - powerpc: smp_mb in kvmppc_prepare_to_enter.
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*
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* There is already an smp_mb__after_atomic() before
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* kvm_make_all_cpus_request() reads vcpu->mode. We reuse that
|
|
* barrier here.
|
|
*/
|
|
if (!kvm_arch_flush_remote_tlb(kvm)
|
|
|| kvm_make_all_cpus_request(kvm, KVM_REQ_TLB_FLUSH))
|
|
++kvm->stat.generic.remote_tlb_flush;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_flush_remote_tlbs);
|
|
#endif
|
|
|
|
static void kvm_flush_shadow_all(struct kvm *kvm)
|
|
{
|
|
kvm_arch_flush_shadow_all(kvm);
|
|
kvm_arch_guest_memory_reclaimed(kvm);
|
|
}
|
|
|
|
#ifdef KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE
|
|
static inline void *mmu_memory_cache_alloc_obj(struct kvm_mmu_memory_cache *mc,
|
|
gfp_t gfp_flags)
|
|
{
|
|
gfp_flags |= mc->gfp_zero;
|
|
|
|
if (mc->kmem_cache)
|
|
return kmem_cache_alloc(mc->kmem_cache, gfp_flags);
|
|
else
|
|
return (void *)__get_free_page(gfp_flags);
|
|
}
|
|
|
|
int __kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int capacity, int min)
|
|
{
|
|
gfp_t gfp = mc->gfp_custom ? mc->gfp_custom : GFP_KERNEL_ACCOUNT;
|
|
void *obj;
|
|
|
|
if (mc->nobjs >= min)
|
|
return 0;
|
|
|
|
if (unlikely(!mc->objects)) {
|
|
if (WARN_ON_ONCE(!capacity))
|
|
return -EIO;
|
|
|
|
mc->objects = kvmalloc_array(sizeof(void *), capacity, gfp);
|
|
if (!mc->objects)
|
|
return -ENOMEM;
|
|
|
|
mc->capacity = capacity;
|
|
}
|
|
|
|
/* It is illegal to request a different capacity across topups. */
|
|
if (WARN_ON_ONCE(mc->capacity != capacity))
|
|
return -EIO;
|
|
|
|
while (mc->nobjs < mc->capacity) {
|
|
obj = mmu_memory_cache_alloc_obj(mc, gfp);
|
|
if (!obj)
|
|
return mc->nobjs >= min ? 0 : -ENOMEM;
|
|
mc->objects[mc->nobjs++] = obj;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int kvm_mmu_topup_memory_cache(struct kvm_mmu_memory_cache *mc, int min)
|
|
{
|
|
return __kvm_mmu_topup_memory_cache(mc, KVM_ARCH_NR_OBJS_PER_MEMORY_CACHE, min);
|
|
}
|
|
|
|
int kvm_mmu_memory_cache_nr_free_objects(struct kvm_mmu_memory_cache *mc)
|
|
{
|
|
return mc->nobjs;
|
|
}
|
|
|
|
void kvm_mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
|
|
{
|
|
while (mc->nobjs) {
|
|
if (mc->kmem_cache)
|
|
kmem_cache_free(mc->kmem_cache, mc->objects[--mc->nobjs]);
|
|
else
|
|
free_page((unsigned long)mc->objects[--mc->nobjs]);
|
|
}
|
|
|
|
kvfree(mc->objects);
|
|
|
|
mc->objects = NULL;
|
|
mc->capacity = 0;
|
|
}
|
|
|
|
void *kvm_mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
|
|
{
|
|
void *p;
|
|
|
|
if (WARN_ON(!mc->nobjs))
|
|
p = mmu_memory_cache_alloc_obj(mc, GFP_ATOMIC | __GFP_ACCOUNT);
|
|
else
|
|
p = mc->objects[--mc->nobjs];
|
|
BUG_ON(!p);
|
|
return p;
|
|
}
|
|
#endif
|
|
|
|
static void kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
|
|
{
|
|
mutex_init(&vcpu->mutex);
|
|
vcpu->cpu = -1;
|
|
vcpu->kvm = kvm;
|
|
vcpu->vcpu_id = id;
|
|
vcpu->pid = NULL;
|
|
#ifndef __KVM_HAVE_ARCH_WQP
|
|
rcuwait_init(&vcpu->wait);
|
|
#endif
|
|
kvm_async_pf_vcpu_init(vcpu);
|
|
|
|
kvm_vcpu_set_in_spin_loop(vcpu, false);
|
|
kvm_vcpu_set_dy_eligible(vcpu, false);
|
|
vcpu->preempted = false;
|
|
vcpu->ready = false;
|
|
preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
|
|
vcpu->last_used_slot = NULL;
|
|
|
|
/* Fill the stats id string for the vcpu */
|
|
snprintf(vcpu->stats_id, sizeof(vcpu->stats_id), "kvm-%d/vcpu-%d",
|
|
task_pid_nr(current), id);
|
|
}
|
|
|
|
static void kvm_vcpu_destroy(struct kvm_vcpu *vcpu)
|
|
{
|
|
kvm_arch_vcpu_destroy(vcpu);
|
|
kvm_dirty_ring_free(&vcpu->dirty_ring);
|
|
|
|
/*
|
|
* No need for rcu_read_lock as VCPU_RUN is the only place that changes
|
|
* the vcpu->pid pointer, and at destruction time all file descriptors
|
|
* are already gone.
|
|
*/
|
|
put_pid(rcu_dereference_protected(vcpu->pid, 1));
|
|
|
|
free_page((unsigned long)vcpu->run);
|
|
kmem_cache_free(kvm_vcpu_cache, vcpu);
|
|
}
|
|
|
|
void kvm_destroy_vcpus(struct kvm *kvm)
|
|
{
|
|
unsigned long i;
|
|
struct kvm_vcpu *vcpu;
|
|
|
|
kvm_for_each_vcpu(i, vcpu, kvm) {
|
|
kvm_vcpu_destroy(vcpu);
|
|
xa_erase(&kvm->vcpu_array, i);
|
|
}
|
|
|
|
atomic_set(&kvm->online_vcpus, 0);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_destroy_vcpus);
|
|
|
|
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
|
|
static inline struct kvm *mmu_notifier_to_kvm(struct mmu_notifier *mn)
|
|
{
|
|
return container_of(mn, struct kvm, mmu_notifier);
|
|
}
|
|
|
|
typedef bool (*hva_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range);
|
|
|
|
typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start,
|
|
unsigned long end);
|
|
|
|
typedef void (*on_unlock_fn_t)(struct kvm *kvm);
|
|
|
|
struct kvm_hva_range {
|
|
unsigned long start;
|
|
unsigned long end;
|
|
pte_t pte;
|
|
hva_handler_t handler;
|
|
on_lock_fn_t on_lock;
|
|
on_unlock_fn_t on_unlock;
|
|
bool flush_on_ret;
|
|
bool may_block;
|
|
};
|
|
|
|
/*
|
|
* Use a dedicated stub instead of NULL to indicate that there is no callback
|
|
* function/handler. The compiler technically can't guarantee that a real
|
|
* function will have a non-zero address, and so it will generate code to
|
|
* check for !NULL, whereas comparing against a stub will be elided at compile
|
|
* time (unless the compiler is getting long in the tooth, e.g. gcc 4.9).
|
|
*/
|
|
static void kvm_null_fn(void)
|
|
{
|
|
|
|
}
|
|
#define IS_KVM_NULL_FN(fn) ((fn) == (void *)kvm_null_fn)
|
|
|
|
/* Iterate over each memslot intersecting [start, last] (inclusive) range */
|
|
#define kvm_for_each_memslot_in_hva_range(node, slots, start, last) \
|
|
for (node = interval_tree_iter_first(&slots->hva_tree, start, last); \
|
|
node; \
|
|
node = interval_tree_iter_next(node, start, last)) \
|
|
|
|
static __always_inline int __kvm_handle_hva_range(struct kvm *kvm,
|
|
const struct kvm_hva_range *range)
|
|
{
|
|
bool ret = false, locked = false;
|
|
struct kvm_gfn_range gfn_range;
|
|
struct kvm_memory_slot *slot;
|
|
struct kvm_memslots *slots;
|
|
int i, idx;
|
|
|
|
if (WARN_ON_ONCE(range->end <= range->start))
|
|
return 0;
|
|
|
|
/* A null handler is allowed if and only if on_lock() is provided. */
|
|
if (WARN_ON_ONCE(IS_KVM_NULL_FN(range->on_lock) &&
|
|
IS_KVM_NULL_FN(range->handler)))
|
|
return 0;
|
|
|
|
idx = srcu_read_lock(&kvm->srcu);
|
|
|
|
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
|
|
struct interval_tree_node *node;
|
|
|
|
slots = __kvm_memslots(kvm, i);
|
|
kvm_for_each_memslot_in_hva_range(node, slots,
|
|
range->start, range->end - 1) {
|
|
unsigned long hva_start, hva_end;
|
|
|
|
slot = container_of(node, struct kvm_memory_slot, hva_node[slots->node_idx]);
|
|
hva_start = max(range->start, slot->userspace_addr);
|
|
hva_end = min(range->end, slot->userspace_addr +
|
|
(slot->npages << PAGE_SHIFT));
|
|
|
|
/*
|
|
* To optimize for the likely case where the address
|
|
* range is covered by zero or one memslots, don't
|
|
* bother making these conditional (to avoid writes on
|
|
* the second or later invocation of the handler).
|
|
*/
|
|
gfn_range.pte = range->pte;
|
|
gfn_range.may_block = range->may_block;
|
|
|
|
/*
|
|
* {gfn(page) | page intersects with [hva_start, hva_end)} =
|
|
* {gfn_start, gfn_start+1, ..., gfn_end-1}.
|
|
*/
|
|
gfn_range.start = hva_to_gfn_memslot(hva_start, slot);
|
|
gfn_range.end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, slot);
|
|
gfn_range.slot = slot;
|
|
|
|
if (!locked) {
|
|
locked = true;
|
|
KVM_MMU_LOCK(kvm);
|
|
if (!IS_KVM_NULL_FN(range->on_lock))
|
|
range->on_lock(kvm, range->start, range->end);
|
|
if (IS_KVM_NULL_FN(range->handler))
|
|
break;
|
|
}
|
|
ret |= range->handler(kvm, &gfn_range);
|
|
}
|
|
}
|
|
|
|
if (range->flush_on_ret && ret)
|
|
kvm_flush_remote_tlbs(kvm);
|
|
|
|
if (locked) {
|
|
KVM_MMU_UNLOCK(kvm);
|
|
if (!IS_KVM_NULL_FN(range->on_unlock))
|
|
range->on_unlock(kvm);
|
|
}
|
|
|
|
srcu_read_unlock(&kvm->srcu, idx);
|
|
|
|
/* The notifiers are averse to booleans. :-( */
|
|
return (int)ret;
|
|
}
|
|
|
|
static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn,
|
|
unsigned long start,
|
|
unsigned long end,
|
|
pte_t pte,
|
|
hva_handler_t handler)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
const struct kvm_hva_range range = {
|
|
.start = start,
|
|
.end = end,
|
|
.pte = pte,
|
|
.handler = handler,
|
|
.on_lock = (void *)kvm_null_fn,
|
|
.on_unlock = (void *)kvm_null_fn,
|
|
.flush_on_ret = true,
|
|
.may_block = false,
|
|
};
|
|
|
|
return __kvm_handle_hva_range(kvm, &range);
|
|
}
|
|
|
|
static __always_inline int kvm_handle_hva_range_no_flush(struct mmu_notifier *mn,
|
|
unsigned long start,
|
|
unsigned long end,
|
|
hva_handler_t handler)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
const struct kvm_hva_range range = {
|
|
.start = start,
|
|
.end = end,
|
|
.pte = __pte(0),
|
|
.handler = handler,
|
|
.on_lock = (void *)kvm_null_fn,
|
|
.on_unlock = (void *)kvm_null_fn,
|
|
.flush_on_ret = false,
|
|
.may_block = false,
|
|
};
|
|
|
|
return __kvm_handle_hva_range(kvm, &range);
|
|
}
|
|
|
|
static bool kvm_change_spte_gfn(struct kvm *kvm, struct kvm_gfn_range *range)
|
|
{
|
|
/*
|
|
* Skipping invalid memslots is correct if and only change_pte() is
|
|
* surrounded by invalidate_range_{start,end}(), which is currently
|
|
* guaranteed by the primary MMU. If that ever changes, KVM needs to
|
|
* unmap the memslot instead of skipping the memslot to ensure that KVM
|
|
* doesn't hold references to the old PFN.
|
|
*/
|
|
WARN_ON_ONCE(!READ_ONCE(kvm->mn_active_invalidate_count));
|
|
|
|
if (range->slot->flags & KVM_MEMSLOT_INVALID)
|
|
return false;
|
|
|
|
return kvm_set_spte_gfn(kvm, range);
|
|
}
|
|
|
|
static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn,
|
|
struct mm_struct *mm,
|
|
unsigned long address,
|
|
pte_t pte)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
|
|
trace_kvm_set_spte_hva(address);
|
|
|
|
/*
|
|
* .change_pte() must be surrounded by .invalidate_range_{start,end}().
|
|
* If mmu_invalidate_in_progress is zero, then no in-progress
|
|
* invalidations, including this one, found a relevant memslot at
|
|
* start(); rechecking memslots here is unnecessary. Note, a false
|
|
* positive (count elevated by a different invalidation) is sub-optimal
|
|
* but functionally ok.
|
|
*/
|
|
WARN_ON_ONCE(!READ_ONCE(kvm->mn_active_invalidate_count));
|
|
if (!READ_ONCE(kvm->mmu_invalidate_in_progress))
|
|
return;
|
|
|
|
kvm_handle_hva_range(mn, address, address + 1, pte, kvm_change_spte_gfn);
|
|
}
|
|
|
|
void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
/*
|
|
* The count increase must become visible at unlock time as no
|
|
* spte can be established without taking the mmu_lock and
|
|
* count is also read inside the mmu_lock critical section.
|
|
*/
|
|
kvm->mmu_invalidate_in_progress++;
|
|
if (likely(kvm->mmu_invalidate_in_progress == 1)) {
|
|
kvm->mmu_invalidate_range_start = start;
|
|
kvm->mmu_invalidate_range_end = end;
|
|
} else {
|
|
/*
|
|
* Fully tracking multiple concurrent ranges has diminishing
|
|
* returns. Keep things simple and just find the minimal range
|
|
* which includes the current and new ranges. As there won't be
|
|
* enough information to subtract a range after its invalidate
|
|
* completes, any ranges invalidated concurrently will
|
|
* accumulate and persist until all outstanding invalidates
|
|
* complete.
|
|
*/
|
|
kvm->mmu_invalidate_range_start =
|
|
min(kvm->mmu_invalidate_range_start, start);
|
|
kvm->mmu_invalidate_range_end =
|
|
max(kvm->mmu_invalidate_range_end, end);
|
|
}
|
|
}
|
|
|
|
static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn,
|
|
const struct mmu_notifier_range *range)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
const struct kvm_hva_range hva_range = {
|
|
.start = range->start,
|
|
.end = range->end,
|
|
.pte = __pte(0),
|
|
.handler = kvm_unmap_gfn_range,
|
|
.on_lock = kvm_mmu_invalidate_begin,
|
|
.on_unlock = kvm_arch_guest_memory_reclaimed,
|
|
.flush_on_ret = true,
|
|
.may_block = mmu_notifier_range_blockable(range),
|
|
};
|
|
|
|
trace_kvm_unmap_hva_range(range->start, range->end);
|
|
|
|
/*
|
|
* Prevent memslot modification between range_start() and range_end()
|
|
* so that conditionally locking provides the same result in both
|
|
* functions. Without that guarantee, the mmu_invalidate_in_progress
|
|
* adjustments will be imbalanced.
|
|
*
|
|
* Pairs with the decrement in range_end().
|
|
*/
|
|
spin_lock(&kvm->mn_invalidate_lock);
|
|
kvm->mn_active_invalidate_count++;
|
|
spin_unlock(&kvm->mn_invalidate_lock);
|
|
|
|
/*
|
|
* Invalidate pfn caches _before_ invalidating the secondary MMUs, i.e.
|
|
* before acquiring mmu_lock, to avoid holding mmu_lock while acquiring
|
|
* each cache's lock. There are relatively few caches in existence at
|
|
* any given time, and the caches themselves can check for hva overlap,
|
|
* i.e. don't need to rely on memslot overlap checks for performance.
|
|
* Because this runs without holding mmu_lock, the pfn caches must use
|
|
* mn_active_invalidate_count (see above) instead of
|
|
* mmu_invalidate_in_progress.
|
|
*/
|
|
gfn_to_pfn_cache_invalidate_start(kvm, range->start, range->end,
|
|
hva_range.may_block);
|
|
|
|
__kvm_handle_hva_range(kvm, &hva_range);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void kvm_mmu_invalidate_end(struct kvm *kvm, unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
/*
|
|
* This sequence increase will notify the kvm page fault that
|
|
* the page that is going to be mapped in the spte could have
|
|
* been freed.
|
|
*/
|
|
kvm->mmu_invalidate_seq++;
|
|
smp_wmb();
|
|
/*
|
|
* The above sequence increase must be visible before the
|
|
* below count decrease, which is ensured by the smp_wmb above
|
|
* in conjunction with the smp_rmb in mmu_invalidate_retry().
|
|
*/
|
|
kvm->mmu_invalidate_in_progress--;
|
|
}
|
|
|
|
static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn,
|
|
const struct mmu_notifier_range *range)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
const struct kvm_hva_range hva_range = {
|
|
.start = range->start,
|
|
.end = range->end,
|
|
.pte = __pte(0),
|
|
.handler = (void *)kvm_null_fn,
|
|
.on_lock = kvm_mmu_invalidate_end,
|
|
.on_unlock = (void *)kvm_null_fn,
|
|
.flush_on_ret = false,
|
|
.may_block = mmu_notifier_range_blockable(range),
|
|
};
|
|
bool wake;
|
|
|
|
__kvm_handle_hva_range(kvm, &hva_range);
|
|
|
|
/* Pairs with the increment in range_start(). */
|
|
spin_lock(&kvm->mn_invalidate_lock);
|
|
wake = (--kvm->mn_active_invalidate_count == 0);
|
|
spin_unlock(&kvm->mn_invalidate_lock);
|
|
|
|
/*
|
|
* There can only be one waiter, since the wait happens under
|
|
* slots_lock.
|
|
*/
|
|
if (wake)
|
|
rcuwait_wake_up(&kvm->mn_memslots_update_rcuwait);
|
|
|
|
BUG_ON(kvm->mmu_invalidate_in_progress < 0);
|
|
}
|
|
|
|
static int kvm_mmu_notifier_clear_flush_young(struct mmu_notifier *mn,
|
|
struct mm_struct *mm,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
trace_kvm_age_hva(start, end);
|
|
|
|
return kvm_handle_hva_range(mn, start, end, __pte(0), kvm_age_gfn);
|
|
}
|
|
|
|
static int kvm_mmu_notifier_clear_young(struct mmu_notifier *mn,
|
|
struct mm_struct *mm,
|
|
unsigned long start,
|
|
unsigned long end)
|
|
{
|
|
trace_kvm_age_hva(start, end);
|
|
|
|
/*
|
|
* Even though we do not flush TLB, this will still adversely
|
|
* affect performance on pre-Haswell Intel EPT, where there is
|
|
* no EPT Access Bit to clear so that we have to tear down EPT
|
|
* tables instead. If we find this unacceptable, we can always
|
|
* add a parameter to kvm_age_hva so that it effectively doesn't
|
|
* do anything on clear_young.
|
|
*
|
|
* Also note that currently we never issue secondary TLB flushes
|
|
* from clear_young, leaving this job up to the regular system
|
|
* cadence. If we find this inaccurate, we might come up with a
|
|
* more sophisticated heuristic later.
|
|
*/
|
|
return kvm_handle_hva_range_no_flush(mn, start, end, kvm_age_gfn);
|
|
}
|
|
|
|
static int kvm_mmu_notifier_test_young(struct mmu_notifier *mn,
|
|
struct mm_struct *mm,
|
|
unsigned long address)
|
|
{
|
|
trace_kvm_test_age_hva(address);
|
|
|
|
return kvm_handle_hva_range_no_flush(mn, address, address + 1,
|
|
kvm_test_age_gfn);
|
|
}
|
|
|
|
static void kvm_mmu_notifier_release(struct mmu_notifier *mn,
|
|
struct mm_struct *mm)
|
|
{
|
|
struct kvm *kvm = mmu_notifier_to_kvm(mn);
|
|
int idx;
|
|
|
|
idx = srcu_read_lock(&kvm->srcu);
|
|
kvm_flush_shadow_all(kvm);
|
|
srcu_read_unlock(&kvm->srcu, idx);
|
|
}
|
|
|
|
static const struct mmu_notifier_ops kvm_mmu_notifier_ops = {
|
|
.invalidate_range_start = kvm_mmu_notifier_invalidate_range_start,
|
|
.invalidate_range_end = kvm_mmu_notifier_invalidate_range_end,
|
|
.clear_flush_young = kvm_mmu_notifier_clear_flush_young,
|
|
.clear_young = kvm_mmu_notifier_clear_young,
|
|
.test_young = kvm_mmu_notifier_test_young,
|
|
.change_pte = kvm_mmu_notifier_change_pte,
|
|
.release = kvm_mmu_notifier_release,
|
|
};
|
|
|
|
static int kvm_init_mmu_notifier(struct kvm *kvm)
|
|
{
|
|
kvm->mmu_notifier.ops = &kvm_mmu_notifier_ops;
|
|
return mmu_notifier_register(&kvm->mmu_notifier, current->mm);
|
|
}
|
|
|
|
#else /* !(CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER) */
|
|
|
|
static int kvm_init_mmu_notifier(struct kvm *kvm)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
#endif /* CONFIG_MMU_NOTIFIER && KVM_ARCH_WANT_MMU_NOTIFIER */
|
|
|
|
#ifdef CONFIG_HAVE_KVM_PM_NOTIFIER
|
|
static int kvm_pm_notifier_call(struct notifier_block *bl,
|
|
unsigned long state,
|
|
void *unused)
|
|
{
|
|
struct kvm *kvm = container_of(bl, struct kvm, pm_notifier);
|
|
|
|
return kvm_arch_pm_notifier(kvm, state);
|
|
}
|
|
|
|
static void kvm_init_pm_notifier(struct kvm *kvm)
|
|
{
|
|
kvm->pm_notifier.notifier_call = kvm_pm_notifier_call;
|
|
/* Suspend KVM before we suspend ftrace, RCU, etc. */
|
|
kvm->pm_notifier.priority = INT_MAX;
|
|
register_pm_notifier(&kvm->pm_notifier);
|
|
}
|
|
|
|
static void kvm_destroy_pm_notifier(struct kvm *kvm)
|
|
{
|
|
unregister_pm_notifier(&kvm->pm_notifier);
|
|
}
|
|
#else /* !CONFIG_HAVE_KVM_PM_NOTIFIER */
|
|
static void kvm_init_pm_notifier(struct kvm *kvm)
|
|
{
|
|
}
|
|
|
|
static void kvm_destroy_pm_notifier(struct kvm *kvm)
|
|
{
|
|
}
|
|
#endif /* CONFIG_HAVE_KVM_PM_NOTIFIER */
|
|
|
|
static void kvm_destroy_dirty_bitmap(struct kvm_memory_slot *memslot)
|
|
{
|
|
if (!memslot->dirty_bitmap)
|
|
return;
|
|
|
|
kvfree(memslot->dirty_bitmap);
|
|
memslot->dirty_bitmap = NULL;
|
|
}
|
|
|
|
/* This does not remove the slot from struct kvm_memslots data structures */
|
|
static void kvm_free_memslot(struct kvm *kvm, struct kvm_memory_slot *slot)
|
|
{
|
|
kvm_destroy_dirty_bitmap(slot);
|
|
|
|
kvm_arch_free_memslot(kvm, slot);
|
|
|
|
kfree(slot);
|
|
}
|
|
|
|
static void kvm_free_memslots(struct kvm *kvm, struct kvm_memslots *slots)
|
|
{
|
|
struct hlist_node *idnode;
|
|
struct kvm_memory_slot *memslot;
|
|
int bkt;
|
|
|
|
/*
|
|
* The same memslot objects live in both active and inactive sets,
|
|
* arbitrarily free using index '1' so the second invocation of this
|
|
* function isn't operating over a structure with dangling pointers
|
|
* (even though this function isn't actually touching them).
|
|
*/
|
|
if (!slots->node_idx)
|
|
return;
|
|
|
|
hash_for_each_safe(slots->id_hash, bkt, idnode, memslot, id_node[1])
|
|
kvm_free_memslot(kvm, memslot);
|
|
}
|
|
|
|
static umode_t kvm_stats_debugfs_mode(const struct _kvm_stats_desc *pdesc)
|
|
{
|
|
switch (pdesc->desc.flags & KVM_STATS_TYPE_MASK) {
|
|
case KVM_STATS_TYPE_INSTANT:
|
|
return 0444;
|
|
case KVM_STATS_TYPE_CUMULATIVE:
|
|
case KVM_STATS_TYPE_PEAK:
|
|
default:
|
|
return 0644;
|
|
}
|
|
}
|
|
|
|
|
|
static void kvm_destroy_vm_debugfs(struct kvm *kvm)
|
|
{
|
|
int i;
|
|
int kvm_debugfs_num_entries = kvm_vm_stats_header.num_desc +
|
|
kvm_vcpu_stats_header.num_desc;
|
|
|
|
if (IS_ERR(kvm->debugfs_dentry))
|
|
return;
|
|
|
|
debugfs_remove_recursive(kvm->debugfs_dentry);
|
|
|
|
if (kvm->debugfs_stat_data) {
|
|
for (i = 0; i < kvm_debugfs_num_entries; i++)
|
|
kfree(kvm->debugfs_stat_data[i]);
|
|
kfree(kvm->debugfs_stat_data);
|
|
}
|
|
}
|
|
|
|
static int kvm_create_vm_debugfs(struct kvm *kvm, const char *fdname)
|
|
{
|
|
static DEFINE_MUTEX(kvm_debugfs_lock);
|
|
struct dentry *dent;
|
|
char dir_name[ITOA_MAX_LEN * 2];
|
|
struct kvm_stat_data *stat_data;
|
|
const struct _kvm_stats_desc *pdesc;
|
|
int i, ret = -ENOMEM;
|
|
int kvm_debugfs_num_entries = kvm_vm_stats_header.num_desc +
|
|
kvm_vcpu_stats_header.num_desc;
|
|
|
|
if (!debugfs_initialized())
|
|
return 0;
|
|
|
|
snprintf(dir_name, sizeof(dir_name), "%d-%s", task_pid_nr(current), fdname);
|
|
mutex_lock(&kvm_debugfs_lock);
|
|
dent = debugfs_lookup(dir_name, kvm_debugfs_dir);
|
|
if (dent) {
|
|
pr_warn_ratelimited("KVM: debugfs: duplicate directory %s\n", dir_name);
|
|
dput(dent);
|
|
mutex_unlock(&kvm_debugfs_lock);
|
|
return 0;
|
|
}
|
|
dent = debugfs_create_dir(dir_name, kvm_debugfs_dir);
|
|
mutex_unlock(&kvm_debugfs_lock);
|
|
if (IS_ERR(dent))
|
|
return 0;
|
|
|
|
kvm->debugfs_dentry = dent;
|
|
kvm->debugfs_stat_data = kcalloc(kvm_debugfs_num_entries,
|
|
sizeof(*kvm->debugfs_stat_data),
|
|
GFP_KERNEL_ACCOUNT);
|
|
if (!kvm->debugfs_stat_data)
|
|
goto out_err;
|
|
|
|
for (i = 0; i < kvm_vm_stats_header.num_desc; ++i) {
|
|
pdesc = &kvm_vm_stats_desc[i];
|
|
stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
|
|
if (!stat_data)
|
|
goto out_err;
|
|
|
|
stat_data->kvm = kvm;
|
|
stat_data->desc = pdesc;
|
|
stat_data->kind = KVM_STAT_VM;
|
|
kvm->debugfs_stat_data[i] = stat_data;
|
|
debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
|
|
kvm->debugfs_dentry, stat_data,
|
|
&stat_fops_per_vm);
|
|
}
|
|
|
|
for (i = 0; i < kvm_vcpu_stats_header.num_desc; ++i) {
|
|
pdesc = &kvm_vcpu_stats_desc[i];
|
|
stat_data = kzalloc(sizeof(*stat_data), GFP_KERNEL_ACCOUNT);
|
|
if (!stat_data)
|
|
goto out_err;
|
|
|
|
stat_data->kvm = kvm;
|
|
stat_data->desc = pdesc;
|
|
stat_data->kind = KVM_STAT_VCPU;
|
|
kvm->debugfs_stat_data[i + kvm_vm_stats_header.num_desc] = stat_data;
|
|
debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
|
|
kvm->debugfs_dentry, stat_data,
|
|
&stat_fops_per_vm);
|
|
}
|
|
|
|
ret = kvm_arch_create_vm_debugfs(kvm);
|
|
if (ret)
|
|
goto out_err;
|
|
|
|
return 0;
|
|
out_err:
|
|
kvm_destroy_vm_debugfs(kvm);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Called after the VM is otherwise initialized, but just before adding it to
|
|
* the vm_list.
|
|
*/
|
|
int __weak kvm_arch_post_init_vm(struct kvm *kvm)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Called just after removing the VM from the vm_list, but before doing any
|
|
* other destruction.
|
|
*/
|
|
void __weak kvm_arch_pre_destroy_vm(struct kvm *kvm)
|
|
{
|
|
}
|
|
|
|
/*
|
|
* Called after per-vm debugfs created. When called kvm->debugfs_dentry should
|
|
* be setup already, so we can create arch-specific debugfs entries under it.
|
|
* Cleanup should be automatic done in kvm_destroy_vm_debugfs() recursively, so
|
|
* a per-arch destroy interface is not needed.
|
|
*/
|
|
int __weak kvm_arch_create_vm_debugfs(struct kvm *kvm)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static struct kvm *kvm_create_vm(unsigned long type, const char *fdname)
|
|
{
|
|
struct kvm *kvm = kvm_arch_alloc_vm();
|
|
struct kvm_memslots *slots;
|
|
int r = -ENOMEM;
|
|
int i, j;
|
|
|
|
if (!kvm)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
/* KVM is pinned via open("/dev/kvm"), the fd passed to this ioctl(). */
|
|
__module_get(kvm_chardev_ops.owner);
|
|
|
|
KVM_MMU_LOCK_INIT(kvm);
|
|
mmgrab(current->mm);
|
|
kvm->mm = current->mm;
|
|
kvm_eventfd_init(kvm);
|
|
mutex_init(&kvm->lock);
|
|
mutex_init(&kvm->irq_lock);
|
|
mutex_init(&kvm->slots_lock);
|
|
mutex_init(&kvm->slots_arch_lock);
|
|
spin_lock_init(&kvm->mn_invalidate_lock);
|
|
rcuwait_init(&kvm->mn_memslots_update_rcuwait);
|
|
xa_init(&kvm->vcpu_array);
|
|
|
|
INIT_LIST_HEAD(&kvm->gpc_list);
|
|
spin_lock_init(&kvm->gpc_lock);
|
|
|
|
INIT_LIST_HEAD(&kvm->devices);
|
|
kvm->max_vcpus = KVM_MAX_VCPUS;
|
|
|
|
BUILD_BUG_ON(KVM_MEM_SLOTS_NUM > SHRT_MAX);
|
|
|
|
/*
|
|
* Force subsequent debugfs file creations to fail if the VM directory
|
|
* is not created (by kvm_create_vm_debugfs()).
|
|
*/
|
|
kvm->debugfs_dentry = ERR_PTR(-ENOENT);
|
|
|
|
snprintf(kvm->stats_id, sizeof(kvm->stats_id), "kvm-%d",
|
|
task_pid_nr(current));
|
|
|
|
if (init_srcu_struct(&kvm->srcu))
|
|
goto out_err_no_srcu;
|
|
if (init_srcu_struct(&kvm->irq_srcu))
|
|
goto out_err_no_irq_srcu;
|
|
|
|
refcount_set(&kvm->users_count, 1);
|
|
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
|
|
for (j = 0; j < 2; j++) {
|
|
slots = &kvm->__memslots[i][j];
|
|
|
|
atomic_long_set(&slots->last_used_slot, (unsigned long)NULL);
|
|
slots->hva_tree = RB_ROOT_CACHED;
|
|
slots->gfn_tree = RB_ROOT;
|
|
hash_init(slots->id_hash);
|
|
slots->node_idx = j;
|
|
|
|
/* Generations must be different for each address space. */
|
|
slots->generation = i;
|
|
}
|
|
|
|
rcu_assign_pointer(kvm->memslots[i], &kvm->__memslots[i][0]);
|
|
}
|
|
|
|
for (i = 0; i < KVM_NR_BUSES; i++) {
|
|
rcu_assign_pointer(kvm->buses[i],
|
|
kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL_ACCOUNT));
|
|
if (!kvm->buses[i])
|
|
goto out_err_no_arch_destroy_vm;
|
|
}
|
|
|
|
r = kvm_arch_init_vm(kvm, type);
|
|
if (r)
|
|
goto out_err_no_arch_destroy_vm;
|
|
|
|
r = hardware_enable_all();
|
|
if (r)
|
|
goto out_err_no_disable;
|
|
|
|
#ifdef CONFIG_HAVE_KVM_IRQFD
|
|
INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
|
|
#endif
|
|
|
|
r = kvm_init_mmu_notifier(kvm);
|
|
if (r)
|
|
goto out_err_no_mmu_notifier;
|
|
|
|
r = kvm_coalesced_mmio_init(kvm);
|
|
if (r < 0)
|
|
goto out_no_coalesced_mmio;
|
|
|
|
r = kvm_create_vm_debugfs(kvm, fdname);
|
|
if (r)
|
|
goto out_err_no_debugfs;
|
|
|
|
r = kvm_arch_post_init_vm(kvm);
|
|
if (r)
|
|
goto out_err;
|
|
|
|
mutex_lock(&kvm_lock);
|
|
list_add(&kvm->vm_list, &vm_list);
|
|
mutex_unlock(&kvm_lock);
|
|
|
|
preempt_notifier_inc();
|
|
kvm_init_pm_notifier(kvm);
|
|
|
|
return kvm;
|
|
|
|
out_err:
|
|
kvm_destroy_vm_debugfs(kvm);
|
|
out_err_no_debugfs:
|
|
kvm_coalesced_mmio_free(kvm);
|
|
out_no_coalesced_mmio:
|
|
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
|
|
if (kvm->mmu_notifier.ops)
|
|
mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
|
|
#endif
|
|
out_err_no_mmu_notifier:
|
|
hardware_disable_all();
|
|
out_err_no_disable:
|
|
kvm_arch_destroy_vm(kvm);
|
|
out_err_no_arch_destroy_vm:
|
|
WARN_ON_ONCE(!refcount_dec_and_test(&kvm->users_count));
|
|
for (i = 0; i < KVM_NR_BUSES; i++)
|
|
kfree(kvm_get_bus(kvm, i));
|
|
cleanup_srcu_struct(&kvm->irq_srcu);
|
|
out_err_no_irq_srcu:
|
|
cleanup_srcu_struct(&kvm->srcu);
|
|
out_err_no_srcu:
|
|
kvm_arch_free_vm(kvm);
|
|
mmdrop(current->mm);
|
|
module_put(kvm_chardev_ops.owner);
|
|
return ERR_PTR(r);
|
|
}
|
|
|
|
static void kvm_destroy_devices(struct kvm *kvm)
|
|
{
|
|
struct kvm_device *dev, *tmp;
|
|
|
|
/*
|
|
* We do not need to take the kvm->lock here, because nobody else
|
|
* has a reference to the struct kvm at this point and therefore
|
|
* cannot access the devices list anyhow.
|
|
*/
|
|
list_for_each_entry_safe(dev, tmp, &kvm->devices, vm_node) {
|
|
list_del(&dev->vm_node);
|
|
dev->ops->destroy(dev);
|
|
}
|
|
}
|
|
|
|
static void kvm_destroy_vm(struct kvm *kvm)
|
|
{
|
|
int i;
|
|
struct mm_struct *mm = kvm->mm;
|
|
|
|
kvm_destroy_pm_notifier(kvm);
|
|
kvm_uevent_notify_change(KVM_EVENT_DESTROY_VM, kvm);
|
|
kvm_destroy_vm_debugfs(kvm);
|
|
kvm_arch_sync_events(kvm);
|
|
mutex_lock(&kvm_lock);
|
|
list_del(&kvm->vm_list);
|
|
mutex_unlock(&kvm_lock);
|
|
kvm_arch_pre_destroy_vm(kvm);
|
|
|
|
kvm_free_irq_routing(kvm);
|
|
for (i = 0; i < KVM_NR_BUSES; i++) {
|
|
struct kvm_io_bus *bus = kvm_get_bus(kvm, i);
|
|
|
|
if (bus)
|
|
kvm_io_bus_destroy(bus);
|
|
kvm->buses[i] = NULL;
|
|
}
|
|
kvm_coalesced_mmio_free(kvm);
|
|
#if defined(CONFIG_MMU_NOTIFIER) && defined(KVM_ARCH_WANT_MMU_NOTIFIER)
|
|
mmu_notifier_unregister(&kvm->mmu_notifier, kvm->mm);
|
|
/*
|
|
* At this point, pending calls to invalidate_range_start()
|
|
* have completed but no more MMU notifiers will run, so
|
|
* mn_active_invalidate_count may remain unbalanced.
|
|
* No threads can be waiting in kvm_swap_active_memslots() as the
|
|
* last reference on KVM has been dropped, but freeing
|
|
* memslots would deadlock without this manual intervention.
|
|
*/
|
|
WARN_ON(rcuwait_active(&kvm->mn_memslots_update_rcuwait));
|
|
kvm->mn_active_invalidate_count = 0;
|
|
#else
|
|
kvm_flush_shadow_all(kvm);
|
|
#endif
|
|
kvm_arch_destroy_vm(kvm);
|
|
kvm_destroy_devices(kvm);
|
|
for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++) {
|
|
kvm_free_memslots(kvm, &kvm->__memslots[i][0]);
|
|
kvm_free_memslots(kvm, &kvm->__memslots[i][1]);
|
|
}
|
|
cleanup_srcu_struct(&kvm->irq_srcu);
|
|
cleanup_srcu_struct(&kvm->srcu);
|
|
kvm_arch_free_vm(kvm);
|
|
preempt_notifier_dec();
|
|
hardware_disable_all();
|
|
mmdrop(mm);
|
|
module_put(kvm_chardev_ops.owner);
|
|
}
|
|
|
|
void kvm_get_kvm(struct kvm *kvm)
|
|
{
|
|
refcount_inc(&kvm->users_count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_get_kvm);
|
|
|
|
/*
|
|
* Make sure the vm is not during destruction, which is a safe version of
|
|
* kvm_get_kvm(). Return true if kvm referenced successfully, false otherwise.
|
|
*/
|
|
bool kvm_get_kvm_safe(struct kvm *kvm)
|
|
{
|
|
return refcount_inc_not_zero(&kvm->users_count);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_get_kvm_safe);
|
|
|
|
void kvm_put_kvm(struct kvm *kvm)
|
|
{
|
|
if (refcount_dec_and_test(&kvm->users_count))
|
|
kvm_destroy_vm(kvm);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_put_kvm);
|
|
|
|
/*
|
|
* Used to put a reference that was taken on behalf of an object associated
|
|
* with a user-visible file descriptor, e.g. a vcpu or device, if installation
|
|
* of the new file descriptor fails and the reference cannot be transferred to
|
|
* its final owner. In such cases, the caller is still actively using @kvm and
|
|
* will fail miserably if the refcount unexpectedly hits zero.
|
|
*/
|
|
void kvm_put_kvm_no_destroy(struct kvm *kvm)
|
|
{
|
|
WARN_ON(refcount_dec_and_test(&kvm->users_count));
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_put_kvm_no_destroy);
|
|
|
|
static int kvm_vm_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct kvm *kvm = filp->private_data;
|
|
|
|
kvm_irqfd_release(kvm);
|
|
|
|
kvm_put_kvm(kvm);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Allocation size is twice as large as the actual dirty bitmap size.
|
|
* See kvm_vm_ioctl_get_dirty_log() why this is needed.
|
|
*/
|
|
static int kvm_alloc_dirty_bitmap(struct kvm_memory_slot *memslot)
|
|
{
|
|
unsigned long dirty_bytes = kvm_dirty_bitmap_bytes(memslot);
|
|
|
|
memslot->dirty_bitmap = __vcalloc(2, dirty_bytes, GFP_KERNEL_ACCOUNT);
|
|
if (!memslot->dirty_bitmap)
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct kvm_memslots *kvm_get_inactive_memslots(struct kvm *kvm, int as_id)
|
|
{
|
|
struct kvm_memslots *active = __kvm_memslots(kvm, as_id);
|
|
int node_idx_inactive = active->node_idx ^ 1;
|
|
|
|
return &kvm->__memslots[as_id][node_idx_inactive];
|
|
}
|
|
|
|
/*
|
|
* Helper to get the address space ID when one of memslot pointers may be NULL.
|
|
* This also serves as a sanity that at least one of the pointers is non-NULL,
|
|
* and that their address space IDs don't diverge.
|
|
*/
|
|
static int kvm_memslots_get_as_id(struct kvm_memory_slot *a,
|
|
struct kvm_memory_slot *b)
|
|
{
|
|
if (WARN_ON_ONCE(!a && !b))
|
|
return 0;
|
|
|
|
if (!a)
|
|
return b->as_id;
|
|
if (!b)
|
|
return a->as_id;
|
|
|
|
WARN_ON_ONCE(a->as_id != b->as_id);
|
|
return a->as_id;
|
|
}
|
|
|
|
static void kvm_insert_gfn_node(struct kvm_memslots *slots,
|
|
struct kvm_memory_slot *slot)
|
|
{
|
|
struct rb_root *gfn_tree = &slots->gfn_tree;
|
|
struct rb_node **node, *parent;
|
|
int idx = slots->node_idx;
|
|
|
|
parent = NULL;
|
|
for (node = &gfn_tree->rb_node; *node; ) {
|
|
struct kvm_memory_slot *tmp;
|
|
|
|
tmp = container_of(*node, struct kvm_memory_slot, gfn_node[idx]);
|
|
parent = *node;
|
|
if (slot->base_gfn < tmp->base_gfn)
|
|
node = &(*node)->rb_left;
|
|
else if (slot->base_gfn > tmp->base_gfn)
|
|
node = &(*node)->rb_right;
|
|
else
|
|
BUG();
|
|
}
|
|
|
|
rb_link_node(&slot->gfn_node[idx], parent, node);
|
|
rb_insert_color(&slot->gfn_node[idx], gfn_tree);
|
|
}
|
|
|
|
static void kvm_erase_gfn_node(struct kvm_memslots *slots,
|
|
struct kvm_memory_slot *slot)
|
|
{
|
|
rb_erase(&slot->gfn_node[slots->node_idx], &slots->gfn_tree);
|
|
}
|
|
|
|
static void kvm_replace_gfn_node(struct kvm_memslots *slots,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new)
|
|
{
|
|
int idx = slots->node_idx;
|
|
|
|
WARN_ON_ONCE(old->base_gfn != new->base_gfn);
|
|
|
|
rb_replace_node(&old->gfn_node[idx], &new->gfn_node[idx],
|
|
&slots->gfn_tree);
|
|
}
|
|
|
|
/*
|
|
* Replace @old with @new in the inactive memslots.
|
|
*
|
|
* With NULL @old this simply adds @new.
|
|
* With NULL @new this simply removes @old.
|
|
*
|
|
* If @new is non-NULL its hva_node[slots_idx] range has to be set
|
|
* appropriately.
|
|
*/
|
|
static void kvm_replace_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new)
|
|
{
|
|
int as_id = kvm_memslots_get_as_id(old, new);
|
|
struct kvm_memslots *slots = kvm_get_inactive_memslots(kvm, as_id);
|
|
int idx = slots->node_idx;
|
|
|
|
if (old) {
|
|
hash_del(&old->id_node[idx]);
|
|
interval_tree_remove(&old->hva_node[idx], &slots->hva_tree);
|
|
|
|
if ((long)old == atomic_long_read(&slots->last_used_slot))
|
|
atomic_long_set(&slots->last_used_slot, (long)new);
|
|
|
|
if (!new) {
|
|
kvm_erase_gfn_node(slots, old);
|
|
return;
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Initialize @new's hva range. Do this even when replacing an @old
|
|
* slot, kvm_copy_memslot() deliberately does not touch node data.
|
|
*/
|
|
new->hva_node[idx].start = new->userspace_addr;
|
|
new->hva_node[idx].last = new->userspace_addr +
|
|
(new->npages << PAGE_SHIFT) - 1;
|
|
|
|
/*
|
|
* (Re)Add the new memslot. There is no O(1) interval_tree_replace(),
|
|
* hva_node needs to be swapped with remove+insert even though hva can't
|
|
* change when replacing an existing slot.
|
|
*/
|
|
hash_add(slots->id_hash, &new->id_node[idx], new->id);
|
|
interval_tree_insert(&new->hva_node[idx], &slots->hva_tree);
|
|
|
|
/*
|
|
* If the memslot gfn is unchanged, rb_replace_node() can be used to
|
|
* switch the node in the gfn tree instead of removing the old and
|
|
* inserting the new as two separate operations. Replacement is a
|
|
* single O(1) operation versus two O(log(n)) operations for
|
|
* remove+insert.
|
|
*/
|
|
if (old && old->base_gfn == new->base_gfn) {
|
|
kvm_replace_gfn_node(slots, old, new);
|
|
} else {
|
|
if (old)
|
|
kvm_erase_gfn_node(slots, old);
|
|
kvm_insert_gfn_node(slots, new);
|
|
}
|
|
}
|
|
|
|
static int check_memory_region_flags(const struct kvm_userspace_memory_region *mem)
|
|
{
|
|
u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES;
|
|
|
|
#ifdef __KVM_HAVE_READONLY_MEM
|
|
valid_flags |= KVM_MEM_READONLY;
|
|
#endif
|
|
|
|
if (mem->flags & ~valid_flags)
|
|
return -EINVAL;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void kvm_swap_active_memslots(struct kvm *kvm, int as_id)
|
|
{
|
|
struct kvm_memslots *slots = kvm_get_inactive_memslots(kvm, as_id);
|
|
|
|
/* Grab the generation from the activate memslots. */
|
|
u64 gen = __kvm_memslots(kvm, as_id)->generation;
|
|
|
|
WARN_ON(gen & KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS);
|
|
slots->generation = gen | KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
|
|
|
|
/*
|
|
* Do not store the new memslots while there are invalidations in
|
|
* progress, otherwise the locking in invalidate_range_start and
|
|
* invalidate_range_end will be unbalanced.
|
|
*/
|
|
spin_lock(&kvm->mn_invalidate_lock);
|
|
prepare_to_rcuwait(&kvm->mn_memslots_update_rcuwait);
|
|
while (kvm->mn_active_invalidate_count) {
|
|
set_current_state(TASK_UNINTERRUPTIBLE);
|
|
spin_unlock(&kvm->mn_invalidate_lock);
|
|
schedule();
|
|
spin_lock(&kvm->mn_invalidate_lock);
|
|
}
|
|
finish_rcuwait(&kvm->mn_memslots_update_rcuwait);
|
|
rcu_assign_pointer(kvm->memslots[as_id], slots);
|
|
spin_unlock(&kvm->mn_invalidate_lock);
|
|
|
|
/*
|
|
* Acquired in kvm_set_memslot. Must be released before synchronize
|
|
* SRCU below in order to avoid deadlock with another thread
|
|
* acquiring the slots_arch_lock in an srcu critical section.
|
|
*/
|
|
mutex_unlock(&kvm->slots_arch_lock);
|
|
|
|
synchronize_srcu_expedited(&kvm->srcu);
|
|
|
|
/*
|
|
* Increment the new memslot generation a second time, dropping the
|
|
* update in-progress flag and incrementing the generation based on
|
|
* the number of address spaces. This provides a unique and easily
|
|
* identifiable generation number while the memslots are in flux.
|
|
*/
|
|
gen = slots->generation & ~KVM_MEMSLOT_GEN_UPDATE_IN_PROGRESS;
|
|
|
|
/*
|
|
* Generations must be unique even across address spaces. We do not need
|
|
* a global counter for that, instead the generation space is evenly split
|
|
* across address spaces. For example, with two address spaces, address
|
|
* space 0 will use generations 0, 2, 4, ... while address space 1 will
|
|
* use generations 1, 3, 5, ...
|
|
*/
|
|
gen += KVM_ADDRESS_SPACE_NUM;
|
|
|
|
kvm_arch_memslots_updated(kvm, gen);
|
|
|
|
slots->generation = gen;
|
|
}
|
|
|
|
static int kvm_prepare_memory_region(struct kvm *kvm,
|
|
const struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new,
|
|
enum kvm_mr_change change)
|
|
{
|
|
int r;
|
|
|
|
/*
|
|
* If dirty logging is disabled, nullify the bitmap; the old bitmap
|
|
* will be freed on "commit". If logging is enabled in both old and
|
|
* new, reuse the existing bitmap. If logging is enabled only in the
|
|
* new and KVM isn't using a ring buffer, allocate and initialize a
|
|
* new bitmap.
|
|
*/
|
|
if (change != KVM_MR_DELETE) {
|
|
if (!(new->flags & KVM_MEM_LOG_DIRTY_PAGES))
|
|
new->dirty_bitmap = NULL;
|
|
else if (old && old->dirty_bitmap)
|
|
new->dirty_bitmap = old->dirty_bitmap;
|
|
else if (kvm_use_dirty_bitmap(kvm)) {
|
|
r = kvm_alloc_dirty_bitmap(new);
|
|
if (r)
|
|
return r;
|
|
|
|
if (kvm_dirty_log_manual_protect_and_init_set(kvm))
|
|
bitmap_set(new->dirty_bitmap, 0, new->npages);
|
|
}
|
|
}
|
|
|
|
r = kvm_arch_prepare_memory_region(kvm, old, new, change);
|
|
|
|
/* Free the bitmap on failure if it was allocated above. */
|
|
if (r && new && new->dirty_bitmap && (!old || !old->dirty_bitmap))
|
|
kvm_destroy_dirty_bitmap(new);
|
|
|
|
return r;
|
|
}
|
|
|
|
static void kvm_commit_memory_region(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
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.
|
|
*/
|
|
if (change == KVM_MR_DELETE)
|
|
kvm->nr_memslot_pages -= old->npages;
|
|
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) {
|
|
case KVM_MR_CREATE:
|
|
/* Nothing more to do. */
|
|
break;
|
|
case KVM_MR_DELETE:
|
|
/* Free the old memslot and all its metadata. */
|
|
kvm_free_memslot(kvm, old);
|
|
break;
|
|
case KVM_MR_MOVE:
|
|
case KVM_MR_FLAGS_ONLY:
|
|
/*
|
|
* Free the dirty bitmap as needed; the below check encompasses
|
|
* both the flags and whether a ring buffer is being used)
|
|
*/
|
|
if (old->dirty_bitmap && !new->dirty_bitmap)
|
|
kvm_destroy_dirty_bitmap(old);
|
|
|
|
/*
|
|
* The final quirk. Free the detached, old slot, but only its
|
|
* memory, not any metadata. Metadata, including arch specific
|
|
* data, may be reused by @new.
|
|
*/
|
|
kfree(old);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Activate @new, which must be installed in the inactive slots by the caller,
|
|
* by swapping the active slots and then propagating @new to @old once @old is
|
|
* unreachable and can be safely modified.
|
|
*
|
|
* With NULL @old this simply adds @new to @active (while swapping the sets).
|
|
* With NULL @new this simply removes @old from @active and frees it
|
|
* (while also swapping the sets).
|
|
*/
|
|
static void kvm_activate_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new)
|
|
{
|
|
int as_id = kvm_memslots_get_as_id(old, new);
|
|
|
|
kvm_swap_active_memslots(kvm, as_id);
|
|
|
|
/* Propagate the new memslot to the now inactive memslots. */
|
|
kvm_replace_memslot(kvm, old, new);
|
|
}
|
|
|
|
static void kvm_copy_memslot(struct kvm_memory_slot *dest,
|
|
const struct kvm_memory_slot *src)
|
|
{
|
|
dest->base_gfn = src->base_gfn;
|
|
dest->npages = src->npages;
|
|
dest->dirty_bitmap = src->dirty_bitmap;
|
|
dest->arch = src->arch;
|
|
dest->userspace_addr = src->userspace_addr;
|
|
dest->flags = src->flags;
|
|
dest->id = src->id;
|
|
dest->as_id = src->as_id;
|
|
}
|
|
|
|
static void kvm_invalidate_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *invalid_slot)
|
|
{
|
|
/*
|
|
* Mark the current slot INVALID. As with all memslot modifications,
|
|
* this must be done on an unreachable slot to avoid modifying the
|
|
* current slot in the active tree.
|
|
*/
|
|
kvm_copy_memslot(invalid_slot, old);
|
|
invalid_slot->flags |= KVM_MEMSLOT_INVALID;
|
|
kvm_replace_memslot(kvm, old, invalid_slot);
|
|
|
|
/*
|
|
* Activate the slot that is now marked INVALID, but don't propagate
|
|
* the slot to the now inactive slots. The slot is either going to be
|
|
* deleted or recreated as a new slot.
|
|
*/
|
|
kvm_swap_active_memslots(kvm, old->as_id);
|
|
|
|
/*
|
|
* From this point no new shadow pages pointing to a deleted, or moved,
|
|
* memslot will be created. Validation of sp->gfn happens in:
|
|
* - gfn_to_hva (kvm_read_guest, gfn_to_pfn)
|
|
* - kvm_is_visible_gfn (mmu_check_root)
|
|
*/
|
|
kvm_arch_flush_shadow_memslot(kvm, old);
|
|
kvm_arch_guest_memory_reclaimed(kvm);
|
|
|
|
/* Was released by kvm_swap_active_memslots(), reacquire. */
|
|
mutex_lock(&kvm->slots_arch_lock);
|
|
|
|
/*
|
|
* Copy the arch-specific field of the newly-installed slot back to the
|
|
* old slot as the arch data could have changed between releasing
|
|
* slots_arch_lock in kvm_swap_active_memslots() and re-acquiring the lock
|
|
* above. Writers are required to retrieve memslots *after* acquiring
|
|
* slots_arch_lock, thus the active slot's data is guaranteed to be fresh.
|
|
*/
|
|
old->arch = invalid_slot->arch;
|
|
}
|
|
|
|
static void kvm_create_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *new)
|
|
{
|
|
/* Add the new memslot to the inactive set and activate. */
|
|
kvm_replace_memslot(kvm, NULL, new);
|
|
kvm_activate_memslot(kvm, NULL, new);
|
|
}
|
|
|
|
static void kvm_delete_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *invalid_slot)
|
|
{
|
|
/*
|
|
* Remove the old memslot (in the inactive memslots) by passing NULL as
|
|
* the "new" slot, and for the invalid version in the active slots.
|
|
*/
|
|
kvm_replace_memslot(kvm, old, NULL);
|
|
kvm_activate_memslot(kvm, invalid_slot, NULL);
|
|
}
|
|
|
|
static void kvm_move_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new,
|
|
struct kvm_memory_slot *invalid_slot)
|
|
{
|
|
/*
|
|
* Replace the old memslot in the inactive slots, and then swap slots
|
|
* and replace the current INVALID with the new as well.
|
|
*/
|
|
kvm_replace_memslot(kvm, old, new);
|
|
kvm_activate_memslot(kvm, invalid_slot, new);
|
|
}
|
|
|
|
static void kvm_update_flags_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new)
|
|
{
|
|
/*
|
|
* Similar to the MOVE case, but the slot doesn't need to be zapped as
|
|
* an intermediate step. Instead, the old memslot is simply replaced
|
|
* with a new, updated copy in both memslot sets.
|
|
*/
|
|
kvm_replace_memslot(kvm, old, new);
|
|
kvm_activate_memslot(kvm, old, new);
|
|
}
|
|
|
|
static int kvm_set_memslot(struct kvm *kvm,
|
|
struct kvm_memory_slot *old,
|
|
struct kvm_memory_slot *new,
|
|
enum kvm_mr_change change)
|
|
{
|
|
struct kvm_memory_slot *invalid_slot;
|
|
int r;
|
|
|
|
/*
|
|
* Released in kvm_swap_active_memslots().
|
|
*
|
|
* Must be held from before the current memslots are copied until after
|
|
* the new memslots are installed with rcu_assign_pointer, then
|
|
* released before the synchronize srcu in kvm_swap_active_memslots().
|
|
*
|
|
* When modifying memslots outside of the slots_lock, must be held
|
|
* before reading the pointer to the current memslots until after all
|
|
* changes to those memslots are complete.
|
|
*
|
|
* These rules ensure that installing new memslots does not lose
|
|
* changes made to the previous memslots.
|
|
*/
|
|
mutex_lock(&kvm->slots_arch_lock);
|
|
|
|
/*
|
|
* Invalidate the old slot if it's being deleted or moved. This is
|
|
* done prior to actually deleting/moving the memslot to allow vCPUs to
|
|
* continue running by ensuring there are no mappings or shadow pages
|
|
* for the memslot when it is deleted/moved. Without pre-invalidation
|
|
* (and without a lock), a window would exist between effecting the
|
|
* delete/move and committing the changes in arch code where KVM or a
|
|
* guest could access a non-existent memslot.
|
|
*
|
|
* Modifications are done on a temporary, unreachable slot. The old
|
|
* slot needs to be preserved in case a later step fails and the
|
|
* invalidation needs to be reverted.
|
|
*/
|
|
if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
|
|
invalid_slot = kzalloc(sizeof(*invalid_slot), GFP_KERNEL_ACCOUNT);
|
|
if (!invalid_slot) {
|
|
mutex_unlock(&kvm->slots_arch_lock);
|
|
return -ENOMEM;
|
|
}
|
|
kvm_invalidate_memslot(kvm, old, invalid_slot);
|
|
}
|
|
|
|
r = kvm_prepare_memory_region(kvm, old, new, change);
|
|
if (r) {
|
|
/*
|
|
* For DELETE/MOVE, revert the above INVALID change. No
|
|
* modifications required since the original slot was preserved
|
|
* in the inactive slots. Changing the active memslots also
|
|
* release slots_arch_lock.
|
|
*/
|
|
if (change == KVM_MR_DELETE || change == KVM_MR_MOVE) {
|
|
kvm_activate_memslot(kvm, invalid_slot, old);
|
|
kfree(invalid_slot);
|
|
} else {
|
|
mutex_unlock(&kvm->slots_arch_lock);
|
|
}
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* For DELETE and MOVE, the working slot is now active as the INVALID
|
|
* version of the old slot. MOVE is particularly special as it reuses
|
|
* the old slot and returns a copy of the old slot (in working_slot).
|
|
* For CREATE, there is no old slot. For DELETE and FLAGS_ONLY, the
|
|
* old slot is detached but otherwise preserved.
|
|
*/
|
|
if (change == KVM_MR_CREATE)
|
|
kvm_create_memslot(kvm, new);
|
|
else if (change == KVM_MR_DELETE)
|
|
kvm_delete_memslot(kvm, old, invalid_slot);
|
|
else if (change == KVM_MR_MOVE)
|
|
kvm_move_memslot(kvm, old, new, invalid_slot);
|
|
else if (change == KVM_MR_FLAGS_ONLY)
|
|
kvm_update_flags_memslot(kvm, old, new);
|
|
else
|
|
BUG();
|
|
|
|
/* Free the temporary INVALID slot used for DELETE and MOVE. */
|
|
if (change == KVM_MR_DELETE || change == KVM_MR_MOVE)
|
|
kfree(invalid_slot);
|
|
|
|
/*
|
|
* No need to refresh new->arch, changes after dropping slots_arch_lock
|
|
* will directly hit the final, active memslot. Architectures are
|
|
* responsible for knowing that new->arch may be stale.
|
|
*/
|
|
kvm_commit_memory_region(kvm, old, new, change);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static bool kvm_check_memslot_overlap(struct kvm_memslots *slots, int id,
|
|
gfn_t start, gfn_t end)
|
|
{
|
|
struct kvm_memslot_iter iter;
|
|
|
|
kvm_for_each_memslot_in_gfn_range(&iter, slots, start, end) {
|
|
if (iter.slot->id != id)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* Allocate some memory and give it an address in the guest physical address
|
|
* space.
|
|
*
|
|
* Discontiguous memory is allowed, mostly for framebuffers.
|
|
*
|
|
* Must be called holding kvm->slots_lock for write.
|
|
*/
|
|
int __kvm_set_memory_region(struct kvm *kvm,
|
|
const struct kvm_userspace_memory_region *mem)
|
|
{
|
|
struct kvm_memory_slot *old, *new;
|
|
struct kvm_memslots *slots;
|
|
enum kvm_mr_change change;
|
|
unsigned long npages;
|
|
gfn_t base_gfn;
|
|
int as_id, id;
|
|
int r;
|
|
|
|
r = check_memory_region_flags(mem);
|
|
if (r)
|
|
return r;
|
|
|
|
as_id = mem->slot >> 16;
|
|
id = (u16)mem->slot;
|
|
|
|
/* General sanity checks */
|
|
if ((mem->memory_size & (PAGE_SIZE - 1)) ||
|
|
(mem->memory_size != (unsigned long)mem->memory_size))
|
|
return -EINVAL;
|
|
if (mem->guest_phys_addr & (PAGE_SIZE - 1))
|
|
return -EINVAL;
|
|
/* We can read the guest memory with __xxx_user() later on. */
|
|
if ((mem->userspace_addr & (PAGE_SIZE - 1)) ||
|
|
(mem->userspace_addr != untagged_addr(mem->userspace_addr)) ||
|
|
!access_ok((void __user *)(unsigned long)mem->userspace_addr,
|
|
mem->memory_size))
|
|
return -EINVAL;
|
|
if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_MEM_SLOTS_NUM)
|
|
return -EINVAL;
|
|
if (mem->guest_phys_addr + mem->memory_size < mem->guest_phys_addr)
|
|
return -EINVAL;
|
|
if ((mem->memory_size >> PAGE_SHIFT) > KVM_MEM_MAX_NR_PAGES)
|
|
return -EINVAL;
|
|
|
|
slots = __kvm_memslots(kvm, as_id);
|
|
|
|
/*
|
|
* Note, the old memslot (and the pointer itself!) may be invalidated
|
|
* and/or destroyed by kvm_set_memslot().
|
|
*/
|
|
old = id_to_memslot(slots, id);
|
|
|
|
if (!mem->memory_size) {
|
|
if (!old || !old->npages)
|
|
return -EINVAL;
|
|
|
|
if (WARN_ON_ONCE(kvm->nr_memslot_pages < old->npages))
|
|
return -EIO;
|
|
|
|
return kvm_set_memslot(kvm, old, NULL, KVM_MR_DELETE);
|
|
}
|
|
|
|
base_gfn = (mem->guest_phys_addr >> PAGE_SHIFT);
|
|
npages = (mem->memory_size >> PAGE_SHIFT);
|
|
|
|
if (!old || !old->npages) {
|
|
change = KVM_MR_CREATE;
|
|
|
|
/*
|
|
* To simplify KVM internals, the total number of pages across
|
|
* all memslots must fit in an unsigned long.
|
|
*/
|
|
if ((kvm->nr_memslot_pages + npages) < kvm->nr_memslot_pages)
|
|
return -EINVAL;
|
|
} else { /* Modify an existing slot. */
|
|
if ((mem->userspace_addr != old->userspace_addr) ||
|
|
(npages != old->npages) ||
|
|
((mem->flags ^ old->flags) & KVM_MEM_READONLY))
|
|
return -EINVAL;
|
|
|
|
if (base_gfn != old->base_gfn)
|
|
change = KVM_MR_MOVE;
|
|
else if (mem->flags != old->flags)
|
|
change = KVM_MR_FLAGS_ONLY;
|
|
else /* Nothing to change. */
|
|
return 0;
|
|
}
|
|
|
|
if ((change == KVM_MR_CREATE || change == KVM_MR_MOVE) &&
|
|
kvm_check_memslot_overlap(slots, id, base_gfn, base_gfn + npages))
|
|
return -EEXIST;
|
|
|
|
/* Allocate a slot that will persist in the memslot. */
|
|
new = kzalloc(sizeof(*new), GFP_KERNEL_ACCOUNT);
|
|
if (!new)
|
|
return -ENOMEM;
|
|
|
|
new->as_id = as_id;
|
|
new->id = id;
|
|
new->base_gfn = base_gfn;
|
|
new->npages = npages;
|
|
new->flags = mem->flags;
|
|
new->userspace_addr = mem->userspace_addr;
|
|
|
|
r = kvm_set_memslot(kvm, old, new, change);
|
|
if (r)
|
|
kfree(new);
|
|
return r;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__kvm_set_memory_region);
|
|
|
|
int kvm_set_memory_region(struct kvm *kvm,
|
|
const struct kvm_userspace_memory_region *mem)
|
|
{
|
|
int r;
|
|
|
|
mutex_lock(&kvm->slots_lock);
|
|
r = __kvm_set_memory_region(kvm, mem);
|
|
mutex_unlock(&kvm->slots_lock);
|
|
return r;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_set_memory_region);
|
|
|
|
static int kvm_vm_ioctl_set_memory_region(struct kvm *kvm,
|
|
struct kvm_userspace_memory_region *mem)
|
|
{
|
|
if ((u16)mem->slot >= KVM_USER_MEM_SLOTS)
|
|
return -EINVAL;
|
|
|
|
return kvm_set_memory_region(kvm, mem);
|
|
}
|
|
|
|
#ifndef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
|
|
/**
|
|
* kvm_get_dirty_log - get a snapshot of dirty pages
|
|
* @kvm: pointer to kvm instance
|
|
* @log: slot id and address to which we copy the log
|
|
* @is_dirty: set to '1' if any dirty pages were found
|
|
* @memslot: set to the associated memslot, always valid on success
|
|
*/
|
|
int kvm_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log,
|
|
int *is_dirty, struct kvm_memory_slot **memslot)
|
|
{
|
|
struct kvm_memslots *slots;
|
|
int i, as_id, id;
|
|
unsigned long n;
|
|
unsigned long any = 0;
|
|
|
|
/* Dirty ring tracking may be exclusive to dirty log tracking */
|
|
if (!kvm_use_dirty_bitmap(kvm))
|
|
return -ENXIO;
|
|
|
|
*memslot = NULL;
|
|
*is_dirty = 0;
|
|
|
|
as_id = log->slot >> 16;
|
|
id = (u16)log->slot;
|
|
if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
|
|
return -EINVAL;
|
|
|
|
slots = __kvm_memslots(kvm, as_id);
|
|
*memslot = id_to_memslot(slots, id);
|
|
if (!(*memslot) || !(*memslot)->dirty_bitmap)
|
|
return -ENOENT;
|
|
|
|
kvm_arch_sync_dirty_log(kvm, *memslot);
|
|
|
|
n = kvm_dirty_bitmap_bytes(*memslot);
|
|
|
|
for (i = 0; !any && i < n/sizeof(long); ++i)
|
|
any = (*memslot)->dirty_bitmap[i];
|
|
|
|
if (copy_to_user(log->dirty_bitmap, (*memslot)->dirty_bitmap, n))
|
|
return -EFAULT;
|
|
|
|
if (any)
|
|
*is_dirty = 1;
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_get_dirty_log);
|
|
|
|
#else /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
|
|
/**
|
|
* kvm_get_dirty_log_protect - get a snapshot of dirty pages
|
|
* and reenable dirty page tracking for the corresponding pages.
|
|
* @kvm: pointer to kvm instance
|
|
* @log: slot id and address to which we copy the log
|
|
*
|
|
* We need to keep it in mind that VCPU threads can write to the bitmap
|
|
* concurrently. So, to avoid losing track of dirty pages we keep the
|
|
* following order:
|
|
*
|
|
* 1. Take a snapshot of the bit and clear it if needed.
|
|
* 2. Write protect the corresponding page.
|
|
* 3. Copy the snapshot to the userspace.
|
|
* 4. Upon return caller flushes TLB's if needed.
|
|
*
|
|
* Between 2 and 4, the guest may write to the page using the remaining TLB
|
|
* entry. This is not a problem because the page is reported dirty using
|
|
* the snapshot taken before and step 4 ensures that writes done after
|
|
* exiting to userspace will be logged for the next call.
|
|
*
|
|
*/
|
|
static int kvm_get_dirty_log_protect(struct kvm *kvm, struct kvm_dirty_log *log)
|
|
{
|
|
struct kvm_memslots *slots;
|
|
struct kvm_memory_slot *memslot;
|
|
int i, as_id, id;
|
|
unsigned long n;
|
|
unsigned long *dirty_bitmap;
|
|
unsigned long *dirty_bitmap_buffer;
|
|
bool flush;
|
|
|
|
/* Dirty ring tracking may be exclusive to dirty log tracking */
|
|
if (!kvm_use_dirty_bitmap(kvm))
|
|
return -ENXIO;
|
|
|
|
as_id = log->slot >> 16;
|
|
id = (u16)log->slot;
|
|
if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
|
|
return -EINVAL;
|
|
|
|
slots = __kvm_memslots(kvm, as_id);
|
|
memslot = id_to_memslot(slots, id);
|
|
if (!memslot || !memslot->dirty_bitmap)
|
|
return -ENOENT;
|
|
|
|
dirty_bitmap = memslot->dirty_bitmap;
|
|
|
|
kvm_arch_sync_dirty_log(kvm, memslot);
|
|
|
|
n = kvm_dirty_bitmap_bytes(memslot);
|
|
flush = false;
|
|
if (kvm->manual_dirty_log_protect) {
|
|
/*
|
|
* Unlike kvm_get_dirty_log, we always return false in *flush,
|
|
* because no flush is needed until KVM_CLEAR_DIRTY_LOG. There
|
|
* is some code duplication between this function and
|
|
* kvm_get_dirty_log, but hopefully all architecture
|
|
* transition to kvm_get_dirty_log_protect and kvm_get_dirty_log
|
|
* can be eliminated.
|
|
*/
|
|
dirty_bitmap_buffer = dirty_bitmap;
|
|
} else {
|
|
dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
|
|
memset(dirty_bitmap_buffer, 0, n);
|
|
|
|
KVM_MMU_LOCK(kvm);
|
|
for (i = 0; i < n / sizeof(long); i++) {
|
|
unsigned long mask;
|
|
gfn_t offset;
|
|
|
|
if (!dirty_bitmap[i])
|
|
continue;
|
|
|
|
flush = true;
|
|
mask = xchg(&dirty_bitmap[i], 0);
|
|
dirty_bitmap_buffer[i] = mask;
|
|
|
|
offset = i * BITS_PER_LONG;
|
|
kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
|
|
offset, mask);
|
|
}
|
|
KVM_MMU_UNLOCK(kvm);
|
|
}
|
|
|
|
if (flush)
|
|
kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
|
|
|
|
if (copy_to_user(log->dirty_bitmap, dirty_bitmap_buffer, n))
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
|
|
/**
|
|
* kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot
|
|
* @kvm: kvm instance
|
|
* @log: slot id and address to which we copy the log
|
|
*
|
|
* Steps 1-4 below provide general overview of dirty page logging. See
|
|
* kvm_get_dirty_log_protect() function description for additional details.
|
|
*
|
|
* We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we
|
|
* always flush the TLB (step 4) even if previous step failed and the dirty
|
|
* bitmap may be corrupt. Regardless of previous outcome the KVM logging API
|
|
* does not preclude user space subsequent dirty log read. Flushing TLB ensures
|
|
* writes will be marked dirty for next log read.
|
|
*
|
|
* 1. Take a snapshot of the bit and clear it if needed.
|
|
* 2. Write protect the corresponding page.
|
|
* 3. Copy the snapshot to the userspace.
|
|
* 4. Flush TLB's if needed.
|
|
*/
|
|
static int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm,
|
|
struct kvm_dirty_log *log)
|
|
{
|
|
int r;
|
|
|
|
mutex_lock(&kvm->slots_lock);
|
|
|
|
r = kvm_get_dirty_log_protect(kvm, log);
|
|
|
|
mutex_unlock(&kvm->slots_lock);
|
|
return r;
|
|
}
|
|
|
|
/**
|
|
* kvm_clear_dirty_log_protect - clear dirty bits in the bitmap
|
|
* and reenable dirty page tracking for the corresponding pages.
|
|
* @kvm: pointer to kvm instance
|
|
* @log: slot id and address from which to fetch the bitmap of dirty pages
|
|
*/
|
|
static int kvm_clear_dirty_log_protect(struct kvm *kvm,
|
|
struct kvm_clear_dirty_log *log)
|
|
{
|
|
struct kvm_memslots *slots;
|
|
struct kvm_memory_slot *memslot;
|
|
int as_id, id;
|
|
gfn_t offset;
|
|
unsigned long i, n;
|
|
unsigned long *dirty_bitmap;
|
|
unsigned long *dirty_bitmap_buffer;
|
|
bool flush;
|
|
|
|
/* Dirty ring tracking may be exclusive to dirty log tracking */
|
|
if (!kvm_use_dirty_bitmap(kvm))
|
|
return -ENXIO;
|
|
|
|
as_id = log->slot >> 16;
|
|
id = (u16)log->slot;
|
|
if (as_id >= KVM_ADDRESS_SPACE_NUM || id >= KVM_USER_MEM_SLOTS)
|
|
return -EINVAL;
|
|
|
|
if (log->first_page & 63)
|
|
return -EINVAL;
|
|
|
|
slots = __kvm_memslots(kvm, as_id);
|
|
memslot = id_to_memslot(slots, id);
|
|
if (!memslot || !memslot->dirty_bitmap)
|
|
return -ENOENT;
|
|
|
|
dirty_bitmap = memslot->dirty_bitmap;
|
|
|
|
n = ALIGN(log->num_pages, BITS_PER_LONG) / 8;
|
|
|
|
if (log->first_page > memslot->npages ||
|
|
log->num_pages > memslot->npages - log->first_page ||
|
|
(log->num_pages < memslot->npages - log->first_page && (log->num_pages & 63)))
|
|
return -EINVAL;
|
|
|
|
kvm_arch_sync_dirty_log(kvm, memslot);
|
|
|
|
flush = false;
|
|
dirty_bitmap_buffer = kvm_second_dirty_bitmap(memslot);
|
|
if (copy_from_user(dirty_bitmap_buffer, log->dirty_bitmap, n))
|
|
return -EFAULT;
|
|
|
|
KVM_MMU_LOCK(kvm);
|
|
for (offset = log->first_page, i = offset / BITS_PER_LONG,
|
|
n = DIV_ROUND_UP(log->num_pages, BITS_PER_LONG); n--;
|
|
i++, offset += BITS_PER_LONG) {
|
|
unsigned long mask = *dirty_bitmap_buffer++;
|
|
atomic_long_t *p = (atomic_long_t *) &dirty_bitmap[i];
|
|
if (!mask)
|
|
continue;
|
|
|
|
mask &= atomic_long_fetch_andnot(mask, p);
|
|
|
|
/*
|
|
* mask contains the bits that really have been cleared. This
|
|
* never includes any bits beyond the length of the memslot (if
|
|
* the length is not aligned to 64 pages), therefore it is not
|
|
* a problem if userspace sets them in log->dirty_bitmap.
|
|
*/
|
|
if (mask) {
|
|
flush = true;
|
|
kvm_arch_mmu_enable_log_dirty_pt_masked(kvm, memslot,
|
|
offset, mask);
|
|
}
|
|
}
|
|
KVM_MMU_UNLOCK(kvm);
|
|
|
|
if (flush)
|
|
kvm_arch_flush_remote_tlbs_memslot(kvm, memslot);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_clear_dirty_log(struct kvm *kvm,
|
|
struct kvm_clear_dirty_log *log)
|
|
{
|
|
int r;
|
|
|
|
mutex_lock(&kvm->slots_lock);
|
|
|
|
r = kvm_clear_dirty_log_protect(kvm, log);
|
|
|
|
mutex_unlock(&kvm->slots_lock);
|
|
return r;
|
|
}
|
|
#endif /* CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT */
|
|
|
|
struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
return __gfn_to_memslot(kvm_memslots(kvm), gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_memslot);
|
|
|
|
struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
struct kvm_memslots *slots = kvm_vcpu_memslots(vcpu);
|
|
u64 gen = slots->generation;
|
|
struct kvm_memory_slot *slot;
|
|
|
|
/*
|
|
* This also protects against using a memslot from a different address space,
|
|
* since different address spaces have different generation numbers.
|
|
*/
|
|
if (unlikely(gen != vcpu->last_used_slot_gen)) {
|
|
vcpu->last_used_slot = NULL;
|
|
vcpu->last_used_slot_gen = gen;
|
|
}
|
|
|
|
slot = try_get_memslot(vcpu->last_used_slot, gfn);
|
|
if (slot)
|
|
return slot;
|
|
|
|
/*
|
|
* Fall back to searching all memslots. We purposely use
|
|
* search_memslots() instead of __gfn_to_memslot() to avoid
|
|
* thrashing the VM-wide last_used_slot in kvm_memslots.
|
|
*/
|
|
slot = search_memslots(slots, gfn, false);
|
|
if (slot) {
|
|
vcpu->last_used_slot = slot;
|
|
return slot;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
bool kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn);
|
|
|
|
return kvm_is_visible_memslot(memslot);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);
|
|
|
|
bool kvm_vcpu_is_visible_gfn(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
struct kvm_memory_slot *memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
|
|
return kvm_is_visible_memslot(memslot);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_is_visible_gfn);
|
|
|
|
unsigned long kvm_host_page_size(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
unsigned long addr, size;
|
|
|
|
size = PAGE_SIZE;
|
|
|
|
addr = kvm_vcpu_gfn_to_hva_prot(vcpu, gfn, NULL);
|
|
if (kvm_is_error_hva(addr))
|
|
return PAGE_SIZE;
|
|
|
|
mmap_read_lock(current->mm);
|
|
vma = find_vma(current->mm, addr);
|
|
if (!vma)
|
|
goto out;
|
|
|
|
size = vma_kernel_pagesize(vma);
|
|
|
|
out:
|
|
mmap_read_unlock(current->mm);
|
|
|
|
return size;
|
|
}
|
|
|
|
static bool memslot_is_readonly(const struct kvm_memory_slot *slot)
|
|
{
|
|
return slot->flags & KVM_MEM_READONLY;
|
|
}
|
|
|
|
static unsigned long __gfn_to_hva_many(const struct kvm_memory_slot *slot, gfn_t gfn,
|
|
gfn_t *nr_pages, bool write)
|
|
{
|
|
if (!slot || slot->flags & KVM_MEMSLOT_INVALID)
|
|
return KVM_HVA_ERR_BAD;
|
|
|
|
if (memslot_is_readonly(slot) && write)
|
|
return KVM_HVA_ERR_RO_BAD;
|
|
|
|
if (nr_pages)
|
|
*nr_pages = slot->npages - (gfn - slot->base_gfn);
|
|
|
|
return __gfn_to_hva_memslot(slot, gfn);
|
|
}
|
|
|
|
static unsigned long gfn_to_hva_many(struct kvm_memory_slot *slot, gfn_t gfn,
|
|
gfn_t *nr_pages)
|
|
{
|
|
return __gfn_to_hva_many(slot, gfn, nr_pages, true);
|
|
}
|
|
|
|
unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot,
|
|
gfn_t gfn)
|
|
{
|
|
return gfn_to_hva_many(slot, gfn, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_hva_memslot);
|
|
|
|
unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
return gfn_to_hva_many(gfn_to_memslot(kvm, gfn), gfn, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_hva);
|
|
|
|
unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
return gfn_to_hva_many(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_hva);
|
|
|
|
/*
|
|
* Return the hva of a @gfn and the R/W attribute if possible.
|
|
*
|
|
* @slot: the kvm_memory_slot which contains @gfn
|
|
* @gfn: the gfn to be translated
|
|
* @writable: used to return the read/write attribute of the @slot if the hva
|
|
* is valid and @writable is not NULL
|
|
*/
|
|
unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot,
|
|
gfn_t gfn, bool *writable)
|
|
{
|
|
unsigned long hva = __gfn_to_hva_many(slot, gfn, NULL, false);
|
|
|
|
if (!kvm_is_error_hva(hva) && writable)
|
|
*writable = !memslot_is_readonly(slot);
|
|
|
|
return hva;
|
|
}
|
|
|
|
unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable)
|
|
{
|
|
struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
|
|
|
|
return gfn_to_hva_memslot_prot(slot, gfn, writable);
|
|
}
|
|
|
|
unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable)
|
|
{
|
|
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
|
|
return gfn_to_hva_memslot_prot(slot, gfn, writable);
|
|
}
|
|
|
|
static inline int check_user_page_hwpoison(unsigned long addr)
|
|
{
|
|
int rc, flags = FOLL_HWPOISON | FOLL_WRITE;
|
|
|
|
rc = get_user_pages(addr, 1, flags, NULL);
|
|
return rc == -EHWPOISON;
|
|
}
|
|
|
|
/*
|
|
* The fast path to get the writable pfn which will be stored in @pfn,
|
|
* true indicates success, otherwise false is returned. It's also the
|
|
* only part that runs if we can in atomic context.
|
|
*/
|
|
static bool hva_to_pfn_fast(unsigned long addr, bool write_fault,
|
|
bool *writable, kvm_pfn_t *pfn)
|
|
{
|
|
struct page *page[1];
|
|
|
|
/*
|
|
* Fast pin a writable pfn only if it is a write fault request
|
|
* or the caller allows to map a writable pfn for a read fault
|
|
* request.
|
|
*/
|
|
if (!(write_fault || writable))
|
|
return false;
|
|
|
|
if (get_user_page_fast_only(addr, FOLL_WRITE, page)) {
|
|
*pfn = page_to_pfn(page[0]);
|
|
|
|
if (writable)
|
|
*writable = true;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/*
|
|
* The slow path to get the pfn of the specified host virtual address,
|
|
* 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 interruptible, bool *writable, kvm_pfn_t *pfn)
|
|
{
|
|
unsigned int flags = FOLL_HWPOISON;
|
|
struct page *page;
|
|
int npages;
|
|
|
|
might_sleep();
|
|
|
|
if (writable)
|
|
*writable = write_fault;
|
|
|
|
if (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)
|
|
return npages;
|
|
|
|
/* map read fault as writable if possible */
|
|
if (unlikely(!write_fault) && writable) {
|
|
struct page *wpage;
|
|
|
|
if (get_user_page_fast_only(addr, FOLL_WRITE, &wpage)) {
|
|
*writable = true;
|
|
put_page(page);
|
|
page = wpage;
|
|
}
|
|
}
|
|
*pfn = page_to_pfn(page);
|
|
return npages;
|
|
}
|
|
|
|
static bool vma_is_valid(struct vm_area_struct *vma, bool write_fault)
|
|
{
|
|
if (unlikely(!(vma->vm_flags & VM_READ)))
|
|
return false;
|
|
|
|
if (write_fault && (unlikely(!(vma->vm_flags & VM_WRITE))))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
static int kvm_try_get_pfn(kvm_pfn_t pfn)
|
|
{
|
|
struct page *page = kvm_pfn_to_refcounted_page(pfn);
|
|
|
|
if (!page)
|
|
return 1;
|
|
|
|
return get_page_unless_zero(page);
|
|
}
|
|
|
|
static int hva_to_pfn_remapped(struct vm_area_struct *vma,
|
|
unsigned long addr, bool write_fault,
|
|
bool *writable, kvm_pfn_t *p_pfn)
|
|
{
|
|
kvm_pfn_t pfn;
|
|
pte_t *ptep;
|
|
pte_t pte;
|
|
spinlock_t *ptl;
|
|
int r;
|
|
|
|
r = follow_pte(vma->vm_mm, addr, &ptep, &ptl);
|
|
if (r) {
|
|
/*
|
|
* get_user_pages fails for VM_IO and VM_PFNMAP vmas and does
|
|
* not call the fault handler, so do it here.
|
|
*/
|
|
bool unlocked = false;
|
|
r = fixup_user_fault(current->mm, addr,
|
|
(write_fault ? FAULT_FLAG_WRITE : 0),
|
|
&unlocked);
|
|
if (unlocked)
|
|
return -EAGAIN;
|
|
if (r)
|
|
return r;
|
|
|
|
r = follow_pte(vma->vm_mm, addr, &ptep, &ptl);
|
|
if (r)
|
|
return r;
|
|
}
|
|
|
|
pte = ptep_get(ptep);
|
|
|
|
if (write_fault && !pte_write(pte)) {
|
|
pfn = KVM_PFN_ERR_RO_FAULT;
|
|
goto out;
|
|
}
|
|
|
|
if (writable)
|
|
*writable = pte_write(pte);
|
|
pfn = pte_pfn(pte);
|
|
|
|
/*
|
|
* Get a reference here because callers of *hva_to_pfn* and
|
|
* *gfn_to_pfn* ultimately call kvm_release_pfn_clean on the
|
|
* returned pfn. This is only needed if the VMA has VM_MIXEDMAP
|
|
* set, but the kvm_try_get_pfn/kvm_release_pfn_clean pair will
|
|
* simply do nothing for reserved pfns.
|
|
*
|
|
* Whoever called remap_pfn_range is also going to call e.g.
|
|
* unmap_mapping_range before the underlying pages are freed,
|
|
* causing a call to our MMU notifier.
|
|
*
|
|
* Certain IO or PFNMAP mappings can be backed with valid
|
|
* struct pages, but be allocated without refcounting e.g.,
|
|
* tail pages of non-compound higher order allocations, which
|
|
* would then underflow the refcount when the caller does the
|
|
* required put_page. Don't allow those pages here.
|
|
*/
|
|
if (!kvm_try_get_pfn(pfn))
|
|
r = -EFAULT;
|
|
|
|
out:
|
|
pte_unmap_unlock(ptep, ptl);
|
|
*p_pfn = pfn;
|
|
|
|
return r;
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
* @writable: whether it allows to map a writable host page for !@write_fault
|
|
*
|
|
* The function will map a writable host page for these two cases:
|
|
* 1): @write_fault = true
|
|
* 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 interruptible,
|
|
bool *async, bool write_fault, bool *writable)
|
|
{
|
|
struct vm_area_struct *vma;
|
|
kvm_pfn_t pfn;
|
|
int npages, r;
|
|
|
|
/* we can do it either atomically or asynchronously, not both */
|
|
BUG_ON(atomic && async);
|
|
|
|
if (hva_to_pfn_fast(addr, write_fault, writable, &pfn))
|
|
return pfn;
|
|
|
|
if (atomic)
|
|
return KVM_PFN_ERR_FAULT;
|
|
|
|
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 ||
|
|
(!async && check_user_page_hwpoison(addr))) {
|
|
pfn = KVM_PFN_ERR_HWPOISON;
|
|
goto exit;
|
|
}
|
|
|
|
retry:
|
|
vma = vma_lookup(current->mm, addr);
|
|
|
|
if (vma == NULL)
|
|
pfn = KVM_PFN_ERR_FAULT;
|
|
else if (vma->vm_flags & (VM_IO | VM_PFNMAP)) {
|
|
r = hva_to_pfn_remapped(vma, addr, write_fault, writable, &pfn);
|
|
if (r == -EAGAIN)
|
|
goto retry;
|
|
if (r < 0)
|
|
pfn = KVM_PFN_ERR_FAULT;
|
|
} else {
|
|
if (async && vma_is_valid(vma, write_fault))
|
|
*async = true;
|
|
pfn = KVM_PFN_ERR_FAULT;
|
|
}
|
|
exit:
|
|
mmap_read_unlock(current->mm);
|
|
return pfn;
|
|
}
|
|
|
|
kvm_pfn_t __gfn_to_pfn_memslot(const struct kvm_memory_slot *slot, gfn_t gfn,
|
|
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);
|
|
|
|
if (hva)
|
|
*hva = addr;
|
|
|
|
if (addr == KVM_HVA_ERR_RO_BAD) {
|
|
if (writable)
|
|
*writable = false;
|
|
return KVM_PFN_ERR_RO_FAULT;
|
|
}
|
|
|
|
if (kvm_is_error_hva(addr)) {
|
|
if (writable)
|
|
*writable = false;
|
|
return KVM_PFN_NOSLOT;
|
|
}
|
|
|
|
/* Do not map writable pfn in the readonly memslot. */
|
|
if (writable && memslot_is_readonly(slot)) {
|
|
*writable = false;
|
|
writable = NULL;
|
|
}
|
|
|
|
return hva_to_pfn(addr, atomic, interruptible, async, write_fault,
|
|
writable);
|
|
}
|
|
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, 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, 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, false, NULL, true,
|
|
NULL, NULL);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_pfn_memslot_atomic);
|
|
|
|
kvm_pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
return gfn_to_pfn_memslot_atomic(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn_atomic);
|
|
|
|
kvm_pfn_t gfn_to_pfn(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
return gfn_to_pfn_memslot(gfn_to_memslot(kvm, gfn), gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_pfn);
|
|
|
|
kvm_pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
return gfn_to_pfn_memslot(kvm_vcpu_gfn_to_memslot(vcpu, gfn), gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_pfn);
|
|
|
|
int gfn_to_page_many_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
|
|
struct page **pages, int nr_pages)
|
|
{
|
|
unsigned long addr;
|
|
gfn_t entry = 0;
|
|
|
|
addr = gfn_to_hva_many(slot, gfn, &entry);
|
|
if (kvm_is_error_hva(addr))
|
|
return -1;
|
|
|
|
if (entry < nr_pages)
|
|
return 0;
|
|
|
|
return get_user_pages_fast_only(addr, nr_pages, FOLL_WRITE, pages);
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_page_many_atomic);
|
|
|
|
/*
|
|
* Do not use this helper unless you are absolutely certain the gfn _must_ be
|
|
* backed by 'struct page'. A valid example is if the backing memslot is
|
|
* controlled by KVM. Note, if the returned page is valid, it's refcount has
|
|
* been elevated by gfn_to_pfn().
|
|
*/
|
|
struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
struct page *page;
|
|
kvm_pfn_t pfn;
|
|
|
|
pfn = gfn_to_pfn(kvm, gfn);
|
|
|
|
if (is_error_noslot_pfn(pfn))
|
|
return KVM_ERR_PTR_BAD_PAGE;
|
|
|
|
page = kvm_pfn_to_refcounted_page(pfn);
|
|
if (!page)
|
|
return KVM_ERR_PTR_BAD_PAGE;
|
|
|
|
return page;
|
|
}
|
|
EXPORT_SYMBOL_GPL(gfn_to_page);
|
|
|
|
void kvm_release_pfn(kvm_pfn_t pfn, bool dirty)
|
|
{
|
|
if (dirty)
|
|
kvm_release_pfn_dirty(pfn);
|
|
else
|
|
kvm_release_pfn_clean(pfn);
|
|
}
|
|
|
|
int kvm_vcpu_map(struct kvm_vcpu *vcpu, gfn_t gfn, struct kvm_host_map *map)
|
|
{
|
|
kvm_pfn_t pfn;
|
|
void *hva = NULL;
|
|
struct page *page = KVM_UNMAPPED_PAGE;
|
|
|
|
if (!map)
|
|
return -EINVAL;
|
|
|
|
pfn = gfn_to_pfn(vcpu->kvm, gfn);
|
|
if (is_error_noslot_pfn(pfn))
|
|
return -EINVAL;
|
|
|
|
if (pfn_valid(pfn)) {
|
|
page = pfn_to_page(pfn);
|
|
hva = kmap(page);
|
|
#ifdef CONFIG_HAS_IOMEM
|
|
} else {
|
|
hva = memremap(pfn_to_hpa(pfn), PAGE_SIZE, MEMREMAP_WB);
|
|
#endif
|
|
}
|
|
|
|
if (!hva)
|
|
return -EFAULT;
|
|
|
|
map->page = page;
|
|
map->hva = hva;
|
|
map->pfn = pfn;
|
|
map->gfn = gfn;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_map);
|
|
|
|
void kvm_vcpu_unmap(struct kvm_vcpu *vcpu, struct kvm_host_map *map, bool dirty)
|
|
{
|
|
if (!map)
|
|
return;
|
|
|
|
if (!map->hva)
|
|
return;
|
|
|
|
if (map->page != KVM_UNMAPPED_PAGE)
|
|
kunmap(map->page);
|
|
#ifdef CONFIG_HAS_IOMEM
|
|
else
|
|
memunmap(map->hva);
|
|
#endif
|
|
|
|
if (dirty)
|
|
kvm_vcpu_mark_page_dirty(vcpu, map->gfn);
|
|
|
|
kvm_release_pfn(map->pfn, dirty);
|
|
|
|
map->hva = NULL;
|
|
map->page = NULL;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_unmap);
|
|
|
|
static bool kvm_is_ad_tracked_page(struct page *page)
|
|
{
|
|
/*
|
|
* Per page-flags.h, pages tagged PG_reserved "should in general not be
|
|
* touched (e.g. set dirty) except by its owner".
|
|
*/
|
|
return !PageReserved(page);
|
|
}
|
|
|
|
static void kvm_set_page_dirty(struct page *page)
|
|
{
|
|
if (kvm_is_ad_tracked_page(page))
|
|
SetPageDirty(page);
|
|
}
|
|
|
|
static void kvm_set_page_accessed(struct page *page)
|
|
{
|
|
if (kvm_is_ad_tracked_page(page))
|
|
mark_page_accessed(page);
|
|
}
|
|
|
|
void kvm_release_page_clean(struct page *page)
|
|
{
|
|
WARN_ON(is_error_page(page));
|
|
|
|
kvm_set_page_accessed(page);
|
|
put_page(page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_release_page_clean);
|
|
|
|
void kvm_release_pfn_clean(kvm_pfn_t pfn)
|
|
{
|
|
struct page *page;
|
|
|
|
if (is_error_noslot_pfn(pfn))
|
|
return;
|
|
|
|
page = kvm_pfn_to_refcounted_page(pfn);
|
|
if (!page)
|
|
return;
|
|
|
|
kvm_release_page_clean(page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_release_pfn_clean);
|
|
|
|
void kvm_release_page_dirty(struct page *page)
|
|
{
|
|
WARN_ON(is_error_page(page));
|
|
|
|
kvm_set_page_dirty(page);
|
|
kvm_release_page_clean(page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_release_page_dirty);
|
|
|
|
void kvm_release_pfn_dirty(kvm_pfn_t pfn)
|
|
{
|
|
struct page *page;
|
|
|
|
if (is_error_noslot_pfn(pfn))
|
|
return;
|
|
|
|
page = kvm_pfn_to_refcounted_page(pfn);
|
|
if (!page)
|
|
return;
|
|
|
|
kvm_release_page_dirty(page);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_release_pfn_dirty);
|
|
|
|
/*
|
|
* Note, checking for an error/noslot pfn is the caller's responsibility when
|
|
* directly marking a page dirty/accessed. Unlike the "release" helpers, the
|
|
* "set" helpers are not to be used when the pfn might point at garbage.
|
|
*/
|
|
void kvm_set_pfn_dirty(kvm_pfn_t pfn)
|
|
{
|
|
if (WARN_ON(is_error_noslot_pfn(pfn)))
|
|
return;
|
|
|
|
if (pfn_valid(pfn))
|
|
kvm_set_page_dirty(pfn_to_page(pfn));
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_set_pfn_dirty);
|
|
|
|
void kvm_set_pfn_accessed(kvm_pfn_t pfn)
|
|
{
|
|
if (WARN_ON(is_error_noslot_pfn(pfn)))
|
|
return;
|
|
|
|
if (pfn_valid(pfn))
|
|
kvm_set_page_accessed(pfn_to_page(pfn));
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_set_pfn_accessed);
|
|
|
|
static int next_segment(unsigned long len, int offset)
|
|
{
|
|
if (len > PAGE_SIZE - offset)
|
|
return PAGE_SIZE - offset;
|
|
else
|
|
return len;
|
|
}
|
|
|
|
static int __kvm_read_guest_page(struct kvm_memory_slot *slot, gfn_t gfn,
|
|
void *data, int offset, int len)
|
|
{
|
|
int r;
|
|
unsigned long addr;
|
|
|
|
addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
|
|
if (kvm_is_error_hva(addr))
|
|
return -EFAULT;
|
|
r = __copy_from_user(data, (void __user *)addr + offset, len);
|
|
if (r)
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset,
|
|
int len)
|
|
{
|
|
struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
|
|
|
|
return __kvm_read_guest_page(slot, gfn, data, offset, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_read_guest_page);
|
|
|
|
int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data,
|
|
int offset, int len)
|
|
{
|
|
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
|
|
return __kvm_read_guest_page(slot, gfn, data, offset, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_page);
|
|
|
|
int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len)
|
|
{
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
int seg;
|
|
int offset = offset_in_page(gpa);
|
|
int ret;
|
|
|
|
while ((seg = next_segment(len, offset)) != 0) {
|
|
ret = kvm_read_guest_page(kvm, gfn, data, offset, seg);
|
|
if (ret < 0)
|
|
return ret;
|
|
offset = 0;
|
|
len -= seg;
|
|
data += seg;
|
|
++gfn;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_read_guest);
|
|
|
|
int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len)
|
|
{
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
int seg;
|
|
int offset = offset_in_page(gpa);
|
|
int ret;
|
|
|
|
while ((seg = next_segment(len, offset)) != 0) {
|
|
ret = kvm_vcpu_read_guest_page(vcpu, gfn, data, offset, seg);
|
|
if (ret < 0)
|
|
return ret;
|
|
offset = 0;
|
|
len -= seg;
|
|
data += seg;
|
|
++gfn;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest);
|
|
|
|
static int __kvm_read_guest_atomic(struct kvm_memory_slot *slot, gfn_t gfn,
|
|
void *data, int offset, unsigned long len)
|
|
{
|
|
int r;
|
|
unsigned long addr;
|
|
|
|
addr = gfn_to_hva_memslot_prot(slot, gfn, NULL);
|
|
if (kvm_is_error_hva(addr))
|
|
return -EFAULT;
|
|
pagefault_disable();
|
|
r = __copy_from_user_inatomic(data, (void __user *)addr + offset, len);
|
|
pagefault_enable();
|
|
if (r)
|
|
return -EFAULT;
|
|
return 0;
|
|
}
|
|
|
|
int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa,
|
|
void *data, unsigned long len)
|
|
{
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
int offset = offset_in_page(gpa);
|
|
|
|
return __kvm_read_guest_atomic(slot, gfn, data, offset, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_read_guest_atomic);
|
|
|
|
static int __kvm_write_guest_page(struct kvm *kvm,
|
|
struct kvm_memory_slot *memslot, gfn_t gfn,
|
|
const void *data, int offset, int len)
|
|
{
|
|
int r;
|
|
unsigned long addr;
|
|
|
|
addr = gfn_to_hva_memslot(memslot, gfn);
|
|
if (kvm_is_error_hva(addr))
|
|
return -EFAULT;
|
|
r = __copy_to_user((void __user *)addr + offset, data, len);
|
|
if (r)
|
|
return -EFAULT;
|
|
mark_page_dirty_in_slot(kvm, memslot, gfn);
|
|
return 0;
|
|
}
|
|
|
|
int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn,
|
|
const void *data, int offset, int len)
|
|
{
|
|
struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn);
|
|
|
|
return __kvm_write_guest_page(kvm, slot, gfn, data, offset, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_write_guest_page);
|
|
|
|
int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn,
|
|
const void *data, int offset, int len)
|
|
{
|
|
struct kvm_memory_slot *slot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
|
|
return __kvm_write_guest_page(vcpu->kvm, slot, gfn, data, offset, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest_page);
|
|
|
|
int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data,
|
|
unsigned long len)
|
|
{
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
int seg;
|
|
int offset = offset_in_page(gpa);
|
|
int ret;
|
|
|
|
while ((seg = next_segment(len, offset)) != 0) {
|
|
ret = kvm_write_guest_page(kvm, gfn, data, offset, seg);
|
|
if (ret < 0)
|
|
return ret;
|
|
offset = 0;
|
|
len -= seg;
|
|
data += seg;
|
|
++gfn;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_write_guest);
|
|
|
|
int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data,
|
|
unsigned long len)
|
|
{
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
int seg;
|
|
int offset = offset_in_page(gpa);
|
|
int ret;
|
|
|
|
while ((seg = next_segment(len, offset)) != 0) {
|
|
ret = kvm_vcpu_write_guest_page(vcpu, gfn, data, offset, seg);
|
|
if (ret < 0)
|
|
return ret;
|
|
offset = 0;
|
|
len -= seg;
|
|
data += seg;
|
|
++gfn;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_write_guest);
|
|
|
|
static int __kvm_gfn_to_hva_cache_init(struct kvm_memslots *slots,
|
|
struct gfn_to_hva_cache *ghc,
|
|
gpa_t gpa, unsigned long len)
|
|
{
|
|
int offset = offset_in_page(gpa);
|
|
gfn_t start_gfn = gpa >> PAGE_SHIFT;
|
|
gfn_t end_gfn = (gpa + len - 1) >> PAGE_SHIFT;
|
|
gfn_t nr_pages_needed = end_gfn - start_gfn + 1;
|
|
gfn_t nr_pages_avail;
|
|
|
|
/* Update ghc->generation before performing any error checks. */
|
|
ghc->generation = slots->generation;
|
|
|
|
if (start_gfn > end_gfn) {
|
|
ghc->hva = KVM_HVA_ERR_BAD;
|
|
return -EINVAL;
|
|
}
|
|
|
|
/*
|
|
* If the requested region crosses two memslots, we still
|
|
* verify that the entire region is valid here.
|
|
*/
|
|
for ( ; start_gfn <= end_gfn; start_gfn += nr_pages_avail) {
|
|
ghc->memslot = __gfn_to_memslot(slots, start_gfn);
|
|
ghc->hva = gfn_to_hva_many(ghc->memslot, start_gfn,
|
|
&nr_pages_avail);
|
|
if (kvm_is_error_hva(ghc->hva))
|
|
return -EFAULT;
|
|
}
|
|
|
|
/* Use the slow path for cross page reads and writes. */
|
|
if (nr_pages_needed == 1)
|
|
ghc->hva += offset;
|
|
else
|
|
ghc->memslot = NULL;
|
|
|
|
ghc->gpa = gpa;
|
|
ghc->len = len;
|
|
return 0;
|
|
}
|
|
|
|
int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
|
|
gpa_t gpa, unsigned long len)
|
|
{
|
|
struct kvm_memslots *slots = kvm_memslots(kvm);
|
|
return __kvm_gfn_to_hva_cache_init(slots, ghc, gpa, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_gfn_to_hva_cache_init);
|
|
|
|
int kvm_write_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
|
|
void *data, unsigned int offset,
|
|
unsigned long len)
|
|
{
|
|
struct kvm_memslots *slots = kvm_memslots(kvm);
|
|
int r;
|
|
gpa_t gpa = ghc->gpa + offset;
|
|
|
|
if (WARN_ON_ONCE(len + offset > ghc->len))
|
|
return -EINVAL;
|
|
|
|
if (slots->generation != ghc->generation) {
|
|
if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (kvm_is_error_hva(ghc->hva))
|
|
return -EFAULT;
|
|
|
|
if (unlikely(!ghc->memslot))
|
|
return kvm_write_guest(kvm, gpa, data, len);
|
|
|
|
r = __copy_to_user((void __user *)ghc->hva + offset, data, len);
|
|
if (r)
|
|
return -EFAULT;
|
|
mark_page_dirty_in_slot(kvm, ghc->memslot, gpa >> PAGE_SHIFT);
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_write_guest_offset_cached);
|
|
|
|
int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
|
|
void *data, unsigned long len)
|
|
{
|
|
return kvm_write_guest_offset_cached(kvm, ghc, data, 0, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_write_guest_cached);
|
|
|
|
int kvm_read_guest_offset_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
|
|
void *data, unsigned int offset,
|
|
unsigned long len)
|
|
{
|
|
struct kvm_memslots *slots = kvm_memslots(kvm);
|
|
int r;
|
|
gpa_t gpa = ghc->gpa + offset;
|
|
|
|
if (WARN_ON_ONCE(len + offset > ghc->len))
|
|
return -EINVAL;
|
|
|
|
if (slots->generation != ghc->generation) {
|
|
if (__kvm_gfn_to_hva_cache_init(slots, ghc, ghc->gpa, ghc->len))
|
|
return -EFAULT;
|
|
}
|
|
|
|
if (kvm_is_error_hva(ghc->hva))
|
|
return -EFAULT;
|
|
|
|
if (unlikely(!ghc->memslot))
|
|
return kvm_read_guest(kvm, gpa, data, len);
|
|
|
|
r = __copy_from_user(data, (void __user *)ghc->hva + offset, len);
|
|
if (r)
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_read_guest_offset_cached);
|
|
|
|
int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc,
|
|
void *data, unsigned long len)
|
|
{
|
|
return kvm_read_guest_offset_cached(kvm, ghc, data, 0, len);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_read_guest_cached);
|
|
|
|
int kvm_clear_guest(struct kvm *kvm, gpa_t gpa, unsigned long len)
|
|
{
|
|
const void *zero_page = (const void *) __va(page_to_phys(ZERO_PAGE(0)));
|
|
gfn_t gfn = gpa >> PAGE_SHIFT;
|
|
int seg;
|
|
int offset = offset_in_page(gpa);
|
|
int ret;
|
|
|
|
while ((seg = next_segment(len, offset)) != 0) {
|
|
ret = kvm_write_guest_page(kvm, gfn, zero_page, offset, len);
|
|
if (ret < 0)
|
|
return ret;
|
|
offset = 0;
|
|
len -= seg;
|
|
++gfn;
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_clear_guest);
|
|
|
|
void mark_page_dirty_in_slot(struct kvm *kvm,
|
|
const struct kvm_memory_slot *memslot,
|
|
gfn_t gfn)
|
|
{
|
|
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
|
|
|
|
#ifdef CONFIG_HAVE_KVM_DIRTY_RING
|
|
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 && vcpu)
|
|
kvm_dirty_ring_push(vcpu, slot, rel_gfn);
|
|
else if (memslot->dirty_bitmap)
|
|
set_bit_le(rel_gfn, memslot->dirty_bitmap);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL_GPL(mark_page_dirty_in_slot);
|
|
|
|
void mark_page_dirty(struct kvm *kvm, gfn_t gfn)
|
|
{
|
|
struct kvm_memory_slot *memslot;
|
|
|
|
memslot = gfn_to_memslot(kvm, gfn);
|
|
mark_page_dirty_in_slot(kvm, memslot, gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(mark_page_dirty);
|
|
|
|
void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn)
|
|
{
|
|
struct kvm_memory_slot *memslot;
|
|
|
|
memslot = kvm_vcpu_gfn_to_memslot(vcpu, gfn);
|
|
mark_page_dirty_in_slot(vcpu->kvm, memslot, gfn);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty);
|
|
|
|
void kvm_sigset_activate(struct kvm_vcpu *vcpu)
|
|
{
|
|
if (!vcpu->sigset_active)
|
|
return;
|
|
|
|
/*
|
|
* This does a lockless modification of ->real_blocked, which is fine
|
|
* because, only current can change ->real_blocked and all readers of
|
|
* ->real_blocked don't care as long ->real_blocked is always a subset
|
|
* of ->blocked.
|
|
*/
|
|
sigprocmask(SIG_SETMASK, &vcpu->sigset, ¤t->real_blocked);
|
|
}
|
|
|
|
void kvm_sigset_deactivate(struct kvm_vcpu *vcpu)
|
|
{
|
|
if (!vcpu->sigset_active)
|
|
return;
|
|
|
|
sigprocmask(SIG_SETMASK, ¤t->real_blocked, NULL);
|
|
sigemptyset(¤t->real_blocked);
|
|
}
|
|
|
|
static void grow_halt_poll_ns(struct kvm_vcpu *vcpu)
|
|
{
|
|
unsigned int old, val, grow, grow_start;
|
|
|
|
old = val = vcpu->halt_poll_ns;
|
|
grow_start = READ_ONCE(halt_poll_ns_grow_start);
|
|
grow = READ_ONCE(halt_poll_ns_grow);
|
|
if (!grow)
|
|
goto out;
|
|
|
|
val *= grow;
|
|
if (val < grow_start)
|
|
val = grow_start;
|
|
|
|
vcpu->halt_poll_ns = val;
|
|
out:
|
|
trace_kvm_halt_poll_ns_grow(vcpu->vcpu_id, val, old);
|
|
}
|
|
|
|
static void shrink_halt_poll_ns(struct kvm_vcpu *vcpu)
|
|
{
|
|
unsigned int old, val, shrink, grow_start;
|
|
|
|
old = val = vcpu->halt_poll_ns;
|
|
shrink = READ_ONCE(halt_poll_ns_shrink);
|
|
grow_start = READ_ONCE(halt_poll_ns_grow_start);
|
|
if (shrink == 0)
|
|
val = 0;
|
|
else
|
|
val /= shrink;
|
|
|
|
if (val < grow_start)
|
|
val = 0;
|
|
|
|
vcpu->halt_poll_ns = val;
|
|
trace_kvm_halt_poll_ns_shrink(vcpu->vcpu_id, val, old);
|
|
}
|
|
|
|
static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
|
|
{
|
|
int ret = -EINTR;
|
|
int idx = srcu_read_lock(&vcpu->kvm->srcu);
|
|
|
|
if (kvm_arch_vcpu_runnable(vcpu))
|
|
goto out;
|
|
if (kvm_cpu_has_pending_timer(vcpu))
|
|
goto out;
|
|
if (signal_pending(current))
|
|
goto out;
|
|
if (kvm_check_request(KVM_REQ_UNBLOCK, vcpu))
|
|
goto out;
|
|
|
|
ret = 0;
|
|
out:
|
|
srcu_read_unlock(&vcpu->kvm->srcu, idx);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Block the vCPU until the vCPU is runnable, an event arrives, or a signal is
|
|
* pending. This is mostly used when halting a vCPU, but may also be used
|
|
* directly for other vCPU non-runnable states, e.g. x86's Wait-For-SIPI.
|
|
*/
|
|
bool kvm_vcpu_block(struct kvm_vcpu *vcpu)
|
|
{
|
|
struct rcuwait *wait = kvm_arch_vcpu_get_wait(vcpu);
|
|
bool waited = false;
|
|
|
|
vcpu->stat.generic.blocking = 1;
|
|
|
|
preempt_disable();
|
|
kvm_arch_vcpu_blocking(vcpu);
|
|
prepare_to_rcuwait(wait);
|
|
preempt_enable();
|
|
|
|
for (;;) {
|
|
set_current_state(TASK_INTERRUPTIBLE);
|
|
|
|
if (kvm_vcpu_check_block(vcpu) < 0)
|
|
break;
|
|
|
|
waited = true;
|
|
schedule();
|
|
}
|
|
|
|
preempt_disable();
|
|
finish_rcuwait(wait);
|
|
kvm_arch_vcpu_unblocking(vcpu);
|
|
preempt_enable();
|
|
|
|
vcpu->stat.generic.blocking = 0;
|
|
|
|
return waited;
|
|
}
|
|
|
|
static inline void update_halt_poll_stats(struct kvm_vcpu *vcpu, ktime_t start,
|
|
ktime_t end, bool success)
|
|
{
|
|
struct kvm_vcpu_stat_generic *stats = &vcpu->stat.generic;
|
|
u64 poll_ns = ktime_to_ns(ktime_sub(end, start));
|
|
|
|
++vcpu->stat.generic.halt_attempted_poll;
|
|
|
|
if (success) {
|
|
++vcpu->stat.generic.halt_successful_poll;
|
|
|
|
if (!vcpu_valid_wakeup(vcpu))
|
|
++vcpu->stat.generic.halt_poll_invalid;
|
|
|
|
stats->halt_poll_success_ns += poll_ns;
|
|
KVM_STATS_LOG_HIST_UPDATE(stats->halt_poll_success_hist, poll_ns);
|
|
} else {
|
|
stats->halt_poll_fail_ns += poll_ns;
|
|
KVM_STATS_LOG_HIST_UPDATE(stats->halt_poll_fail_hist, poll_ns);
|
|
}
|
|
}
|
|
|
|
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
|
|
* expensive block+unblock sequence if a wake event arrives soon after the vCPU
|
|
* is halted.
|
|
*/
|
|
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);
|
|
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 {
|
|
if (kvm_vcpu_check_block(vcpu) < 0)
|
|
goto out;
|
|
cpu_relax();
|
|
poll_end = cur = ktime_get();
|
|
} while (kvm_vcpu_can_poll(cur, stop));
|
|
}
|
|
|
|
waited = kvm_vcpu_block(vcpu);
|
|
|
|
cur = ktime_get();
|
|
if (waited) {
|
|
vcpu->stat.generic.halt_wait_ns +=
|
|
ktime_to_ns(cur) - ktime_to_ns(poll_end);
|
|
KVM_STATS_LOG_HIST_UPDATE(vcpu->stat.generic.halt_wait_hist,
|
|
ktime_to_ns(cur) - ktime_to_ns(poll_end));
|
|
}
|
|
out:
|
|
/* The total time the vCPU was "halted", including polling time. */
|
|
halt_ns = ktime_to_ns(cur) - ktime_to_ns(start);
|
|
|
|
/*
|
|
* Note, halt-polling is considered successful so long as the vCPU was
|
|
* never actually scheduled out, i.e. even if the wake event arrived
|
|
* after of the halt-polling loop itself, but before the full wait.
|
|
*/
|
|
if (do_halt_poll)
|
|
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 (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 > 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 < max_halt_poll_ns &&
|
|
halt_ns < max_halt_poll_ns)
|
|
grow_halt_poll_ns(vcpu);
|
|
} else {
|
|
vcpu->halt_poll_ns = 0;
|
|
}
|
|
}
|
|
|
|
trace_kvm_vcpu_wakeup(halt_ns, waited, vcpu_valid_wakeup(vcpu));
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_halt);
|
|
|
|
bool kvm_vcpu_wake_up(struct kvm_vcpu *vcpu)
|
|
{
|
|
if (__kvm_vcpu_wake_up(vcpu)) {
|
|
WRITE_ONCE(vcpu->ready, true);
|
|
++vcpu->stat.generic.halt_wakeup;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_wake_up);
|
|
|
|
#ifndef CONFIG_S390
|
|
/*
|
|
* Kick a sleeping VCPU, or a guest VCPU in guest mode, into host kernel mode.
|
|
*/
|
|
void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
|
|
{
|
|
int me, cpu;
|
|
|
|
if (kvm_vcpu_wake_up(vcpu))
|
|
return;
|
|
|
|
me = get_cpu();
|
|
/*
|
|
* The only state change done outside the vcpu mutex is IN_GUEST_MODE
|
|
* to EXITING_GUEST_MODE. Therefore the moderately expensive "should
|
|
* kick" check does not need atomic operations if kvm_vcpu_kick is used
|
|
* within the vCPU thread itself.
|
|
*/
|
|
if (vcpu == __this_cpu_read(kvm_running_vcpu)) {
|
|
if (vcpu->mode == IN_GUEST_MODE)
|
|
WRITE_ONCE(vcpu->mode, EXITING_GUEST_MODE);
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Note, the vCPU could get migrated to a different pCPU at any point
|
|
* after kvm_arch_vcpu_should_kick(), which could result in sending an
|
|
* IPI to the previous pCPU. But, that's ok because the purpose of the
|
|
* IPI is to force the vCPU to leave IN_GUEST_MODE, and migrating the
|
|
* vCPU also requires it to leave IN_GUEST_MODE.
|
|
*/
|
|
if (kvm_arch_vcpu_should_kick(vcpu)) {
|
|
cpu = READ_ONCE(vcpu->cpu);
|
|
if (cpu != me && (unsigned)cpu < nr_cpu_ids && cpu_online(cpu))
|
|
smp_send_reschedule(cpu);
|
|
}
|
|
out:
|
|
put_cpu();
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_kick);
|
|
#endif /* !CONFIG_S390 */
|
|
|
|
int kvm_vcpu_yield_to(struct kvm_vcpu *target)
|
|
{
|
|
struct pid *pid;
|
|
struct task_struct *task = NULL;
|
|
int ret = 0;
|
|
|
|
rcu_read_lock();
|
|
pid = rcu_dereference(target->pid);
|
|
if (pid)
|
|
task = get_pid_task(pid, PIDTYPE_PID);
|
|
rcu_read_unlock();
|
|
if (!task)
|
|
return ret;
|
|
ret = yield_to(task, 1);
|
|
put_task_struct(task);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_yield_to);
|
|
|
|
/*
|
|
* Helper that checks whether a VCPU is eligible for directed yield.
|
|
* Most eligible candidate to yield is decided by following heuristics:
|
|
*
|
|
* (a) VCPU which has not done pl-exit or cpu relax intercepted recently
|
|
* (preempted lock holder), indicated by @in_spin_loop.
|
|
* Set at the beginning and cleared at the end of interception/PLE handler.
|
|
*
|
|
* (b) VCPU which has done pl-exit/ cpu relax intercepted but did not get
|
|
* chance last time (mostly it has become eligible now since we have probably
|
|
* yielded to lockholder in last iteration. This is done by toggling
|
|
* @dy_eligible each time a VCPU checked for eligibility.)
|
|
*
|
|
* Yielding to a recently pl-exited/cpu relax intercepted VCPU before yielding
|
|
* to preempted lock-holder could result in wrong VCPU selection and CPU
|
|
* burning. Giving priority for a potential lock-holder increases lock
|
|
* progress.
|
|
*
|
|
* Since algorithm is based on heuristics, accessing another VCPU data without
|
|
* locking does not harm. It may result in trying to yield to same VCPU, fail
|
|
* and continue with next VCPU and so on.
|
|
*/
|
|
static bool kvm_vcpu_eligible_for_directed_yield(struct kvm_vcpu *vcpu)
|
|
{
|
|
#ifdef CONFIG_HAVE_KVM_CPU_RELAX_INTERCEPT
|
|
bool eligible;
|
|
|
|
eligible = !vcpu->spin_loop.in_spin_loop ||
|
|
vcpu->spin_loop.dy_eligible;
|
|
|
|
if (vcpu->spin_loop.in_spin_loop)
|
|
kvm_vcpu_set_dy_eligible(vcpu, !vcpu->spin_loop.dy_eligible);
|
|
|
|
return eligible;
|
|
#else
|
|
return true;
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* Unlike kvm_arch_vcpu_runnable, this function is called outside
|
|
* a vcpu_load/vcpu_put pair. However, for most architectures
|
|
* kvm_arch_vcpu_runnable does not require vcpu_load.
|
|
*/
|
|
bool __weak kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
|
|
{
|
|
return kvm_arch_vcpu_runnable(vcpu);
|
|
}
|
|
|
|
static bool vcpu_dy_runnable(struct kvm_vcpu *vcpu)
|
|
{
|
|
if (kvm_arch_dy_runnable(vcpu))
|
|
return true;
|
|
|
|
#ifdef CONFIG_KVM_ASYNC_PF
|
|
if (!list_empty_careful(&vcpu->async_pf.done))
|
|
return true;
|
|
#endif
|
|
|
|
return false;
|
|
}
|
|
|
|
bool __weak kvm_arch_dy_has_pending_interrupt(struct kvm_vcpu *vcpu)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
void kvm_vcpu_on_spin(struct kvm_vcpu *me, bool yield_to_kernel_mode)
|
|
{
|
|
struct kvm *kvm = me->kvm;
|
|
struct kvm_vcpu *vcpu;
|
|
int last_boosted_vcpu = me->kvm->last_boosted_vcpu;
|
|
unsigned long i;
|
|
int yielded = 0;
|
|
int try = 3;
|
|
int pass;
|
|
|
|
kvm_vcpu_set_in_spin_loop(me, true);
|
|
/*
|
|
* We boost the priority of a VCPU that is runnable but not
|
|
* currently running, because it got preempted by something
|
|
* else and called schedule in __vcpu_run. Hopefully that
|
|
* VCPU is holding the lock that we need and will release it.
|
|
* We approximate round-robin by starting at the last boosted VCPU.
|
|
*/
|
|
for (pass = 0; pass < 2 && !yielded && try; pass++) {
|
|
kvm_for_each_vcpu(i, vcpu, kvm) {
|
|
if (!pass && i <= last_boosted_vcpu) {
|
|
i = last_boosted_vcpu;
|
|
continue;
|
|
} else if (pass && i > last_boosted_vcpu)
|
|
break;
|
|
if (!READ_ONCE(vcpu->ready))
|
|
continue;
|
|
if (vcpu == me)
|
|
continue;
|
|
if (kvm_vcpu_is_blocking(vcpu) && !vcpu_dy_runnable(vcpu))
|
|
continue;
|
|
if (READ_ONCE(vcpu->preempted) && yield_to_kernel_mode &&
|
|
!kvm_arch_dy_has_pending_interrupt(vcpu) &&
|
|
!kvm_arch_vcpu_in_kernel(vcpu))
|
|
continue;
|
|
if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
|
|
continue;
|
|
|
|
yielded = kvm_vcpu_yield_to(vcpu);
|
|
if (yielded > 0) {
|
|
kvm->last_boosted_vcpu = i;
|
|
break;
|
|
} else if (yielded < 0) {
|
|
try--;
|
|
if (!try)
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
kvm_vcpu_set_in_spin_loop(me, false);
|
|
|
|
/* Ensure vcpu is not eligible during next spinloop */
|
|
kvm_vcpu_set_dy_eligible(me, false);
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_vcpu_on_spin);
|
|
|
|
static bool kvm_page_in_dirty_ring(struct kvm *kvm, unsigned long pgoff)
|
|
{
|
|
#ifdef CONFIG_HAVE_KVM_DIRTY_RING
|
|
return (pgoff >= KVM_DIRTY_LOG_PAGE_OFFSET) &&
|
|
(pgoff < KVM_DIRTY_LOG_PAGE_OFFSET +
|
|
kvm->dirty_ring_size / PAGE_SIZE);
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
|
|
static vm_fault_t kvm_vcpu_fault(struct vm_fault *vmf)
|
|
{
|
|
struct kvm_vcpu *vcpu = vmf->vma->vm_file->private_data;
|
|
struct page *page;
|
|
|
|
if (vmf->pgoff == 0)
|
|
page = virt_to_page(vcpu->run);
|
|
#ifdef CONFIG_X86
|
|
else if (vmf->pgoff == KVM_PIO_PAGE_OFFSET)
|
|
page = virt_to_page(vcpu->arch.pio_data);
|
|
#endif
|
|
#ifdef CONFIG_KVM_MMIO
|
|
else if (vmf->pgoff == KVM_COALESCED_MMIO_PAGE_OFFSET)
|
|
page = virt_to_page(vcpu->kvm->coalesced_mmio_ring);
|
|
#endif
|
|
else if (kvm_page_in_dirty_ring(vcpu->kvm, vmf->pgoff))
|
|
page = kvm_dirty_ring_get_page(
|
|
&vcpu->dirty_ring,
|
|
vmf->pgoff - KVM_DIRTY_LOG_PAGE_OFFSET);
|
|
else
|
|
return kvm_arch_vcpu_fault(vcpu, vmf);
|
|
get_page(page);
|
|
vmf->page = page;
|
|
return 0;
|
|
}
|
|
|
|
static const struct vm_operations_struct kvm_vcpu_vm_ops = {
|
|
.fault = kvm_vcpu_fault,
|
|
};
|
|
|
|
static int kvm_vcpu_mmap(struct file *file, struct vm_area_struct *vma)
|
|
{
|
|
struct kvm_vcpu *vcpu = file->private_data;
|
|
unsigned long pages = vma_pages(vma);
|
|
|
|
if ((kvm_page_in_dirty_ring(vcpu->kvm, vma->vm_pgoff) ||
|
|
kvm_page_in_dirty_ring(vcpu->kvm, vma->vm_pgoff + pages - 1)) &&
|
|
((vma->vm_flags & VM_EXEC) || !(vma->vm_flags & VM_SHARED)))
|
|
return -EINVAL;
|
|
|
|
vma->vm_ops = &kvm_vcpu_vm_ops;
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_vcpu_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct kvm_vcpu *vcpu = filp->private_data;
|
|
|
|
kvm_put_kvm(vcpu->kvm);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations kvm_vcpu_fops = {
|
|
.release = kvm_vcpu_release,
|
|
.unlocked_ioctl = kvm_vcpu_ioctl,
|
|
.mmap = kvm_vcpu_mmap,
|
|
.llseek = noop_llseek,
|
|
KVM_COMPAT(kvm_vcpu_compat_ioctl),
|
|
};
|
|
|
|
/*
|
|
* Allocates an inode for the vcpu.
|
|
*/
|
|
static int create_vcpu_fd(struct kvm_vcpu *vcpu)
|
|
{
|
|
char name[8 + 1 + ITOA_MAX_LEN + 1];
|
|
|
|
snprintf(name, sizeof(name), "kvm-vcpu:%d", vcpu->vcpu_id);
|
|
return anon_inode_getfd(name, &kvm_vcpu_fops, vcpu, O_RDWR | O_CLOEXEC);
|
|
}
|
|
|
|
#ifdef __KVM_HAVE_ARCH_VCPU_DEBUGFS
|
|
static int vcpu_get_pid(void *data, u64 *val)
|
|
{
|
|
struct kvm_vcpu *vcpu = data;
|
|
|
|
rcu_read_lock();
|
|
*val = pid_nr(rcu_dereference(vcpu->pid));
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(vcpu_get_pid_fops, vcpu_get_pid, NULL, "%llu\n");
|
|
|
|
static void kvm_create_vcpu_debugfs(struct kvm_vcpu *vcpu)
|
|
{
|
|
struct dentry *debugfs_dentry;
|
|
char dir_name[ITOA_MAX_LEN * 2];
|
|
|
|
if (!debugfs_initialized())
|
|
return;
|
|
|
|
snprintf(dir_name, sizeof(dir_name), "vcpu%d", vcpu->vcpu_id);
|
|
debugfs_dentry = debugfs_create_dir(dir_name,
|
|
vcpu->kvm->debugfs_dentry);
|
|
debugfs_create_file("pid", 0444, debugfs_dentry, vcpu,
|
|
&vcpu_get_pid_fops);
|
|
|
|
kvm_arch_create_vcpu_debugfs(vcpu, debugfs_dentry);
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Creates some virtual cpus. Good luck creating more than one.
|
|
*/
|
|
static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
|
|
{
|
|
int r;
|
|
struct kvm_vcpu *vcpu;
|
|
struct page *page;
|
|
|
|
if (id >= KVM_MAX_VCPU_IDS)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
if (kvm->created_vcpus >= kvm->max_vcpus) {
|
|
mutex_unlock(&kvm->lock);
|
|
return -EINVAL;
|
|
}
|
|
|
|
r = kvm_arch_vcpu_precreate(kvm, id);
|
|
if (r) {
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
kvm->created_vcpus++;
|
|
mutex_unlock(&kvm->lock);
|
|
|
|
vcpu = kmem_cache_zalloc(kvm_vcpu_cache, GFP_KERNEL_ACCOUNT);
|
|
if (!vcpu) {
|
|
r = -ENOMEM;
|
|
goto vcpu_decrement;
|
|
}
|
|
|
|
BUILD_BUG_ON(sizeof(struct kvm_run) > PAGE_SIZE);
|
|
page = alloc_page(GFP_KERNEL_ACCOUNT | __GFP_ZERO);
|
|
if (!page) {
|
|
r = -ENOMEM;
|
|
goto vcpu_free;
|
|
}
|
|
vcpu->run = page_address(page);
|
|
|
|
kvm_vcpu_init(vcpu, kvm, id);
|
|
|
|
r = kvm_arch_vcpu_create(vcpu);
|
|
if (r)
|
|
goto vcpu_free_run_page;
|
|
|
|
if (kvm->dirty_ring_size) {
|
|
r = kvm_dirty_ring_alloc(&vcpu->dirty_ring,
|
|
id, kvm->dirty_ring_size);
|
|
if (r)
|
|
goto arch_vcpu_destroy;
|
|
}
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
#ifdef CONFIG_LOCKDEP
|
|
/* Ensure that lockdep knows vcpu->mutex is taken *inside* kvm->lock */
|
|
mutex_lock(&vcpu->mutex);
|
|
mutex_unlock(&vcpu->mutex);
|
|
#endif
|
|
|
|
if (kvm_get_vcpu_by_id(kvm, id)) {
|
|
r = -EEXIST;
|
|
goto unlock_vcpu_destroy;
|
|
}
|
|
|
|
vcpu->vcpu_idx = atomic_read(&kvm->online_vcpus);
|
|
r = xa_reserve(&kvm->vcpu_array, vcpu->vcpu_idx, GFP_KERNEL_ACCOUNT);
|
|
if (r)
|
|
goto unlock_vcpu_destroy;
|
|
|
|
/* Now it's all set up, let userspace reach it */
|
|
kvm_get_kvm(kvm);
|
|
r = create_vcpu_fd(vcpu);
|
|
if (r < 0)
|
|
goto kvm_put_xa_release;
|
|
|
|
if (KVM_BUG_ON(xa_store(&kvm->vcpu_array, vcpu->vcpu_idx, vcpu, 0), kvm)) {
|
|
r = -EINVAL;
|
|
goto kvm_put_xa_release;
|
|
}
|
|
|
|
/*
|
|
* Pairs with smp_rmb() in kvm_get_vcpu. Store the vcpu
|
|
* pointer before kvm->online_vcpu's incremented value.
|
|
*/
|
|
smp_wmb();
|
|
atomic_inc(&kvm->online_vcpus);
|
|
|
|
mutex_unlock(&kvm->lock);
|
|
kvm_arch_vcpu_postcreate(vcpu);
|
|
kvm_create_vcpu_debugfs(vcpu);
|
|
return r;
|
|
|
|
kvm_put_xa_release:
|
|
kvm_put_kvm_no_destroy(kvm);
|
|
xa_release(&kvm->vcpu_array, vcpu->vcpu_idx);
|
|
unlock_vcpu_destroy:
|
|
mutex_unlock(&kvm->lock);
|
|
kvm_dirty_ring_free(&vcpu->dirty_ring);
|
|
arch_vcpu_destroy:
|
|
kvm_arch_vcpu_destroy(vcpu);
|
|
vcpu_free_run_page:
|
|
free_page((unsigned long)vcpu->run);
|
|
vcpu_free:
|
|
kmem_cache_free(kvm_vcpu_cache, vcpu);
|
|
vcpu_decrement:
|
|
mutex_lock(&kvm->lock);
|
|
kvm->created_vcpus--;
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
static int kvm_vcpu_ioctl_set_sigmask(struct kvm_vcpu *vcpu, sigset_t *sigset)
|
|
{
|
|
if (sigset) {
|
|
sigdelsetmask(sigset, sigmask(SIGKILL)|sigmask(SIGSTOP));
|
|
vcpu->sigset_active = 1;
|
|
vcpu->sigset = *sigset;
|
|
} else
|
|
vcpu->sigset_active = 0;
|
|
return 0;
|
|
}
|
|
|
|
static ssize_t kvm_vcpu_stats_read(struct file *file, char __user *user_buffer,
|
|
size_t size, loff_t *offset)
|
|
{
|
|
struct kvm_vcpu *vcpu = file->private_data;
|
|
|
|
return kvm_stats_read(vcpu->stats_id, &kvm_vcpu_stats_header,
|
|
&kvm_vcpu_stats_desc[0], &vcpu->stat,
|
|
sizeof(vcpu->stat), user_buffer, size, offset);
|
|
}
|
|
|
|
static const struct file_operations kvm_vcpu_stats_fops = {
|
|
.read = kvm_vcpu_stats_read,
|
|
.llseek = noop_llseek,
|
|
};
|
|
|
|
static int kvm_vcpu_ioctl_get_stats_fd(struct kvm_vcpu *vcpu)
|
|
{
|
|
int fd;
|
|
struct file *file;
|
|
char name[15 + ITOA_MAX_LEN + 1];
|
|
|
|
snprintf(name, sizeof(name), "kvm-vcpu-stats:%d", vcpu->vcpu_id);
|
|
|
|
fd = get_unused_fd_flags(O_CLOEXEC);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
file = anon_inode_getfile(name, &kvm_vcpu_stats_fops, vcpu, O_RDONLY);
|
|
if (IS_ERR(file)) {
|
|
put_unused_fd(fd);
|
|
return PTR_ERR(file);
|
|
}
|
|
file->f_mode |= FMODE_PREAD;
|
|
fd_install(fd, file);
|
|
|
|
return fd;
|
|
}
|
|
|
|
static long kvm_vcpu_ioctl(struct file *filp,
|
|
unsigned int ioctl, unsigned long arg)
|
|
{
|
|
struct kvm_vcpu *vcpu = filp->private_data;
|
|
void __user *argp = (void __user *)arg;
|
|
int r;
|
|
struct kvm_fpu *fpu = NULL;
|
|
struct kvm_sregs *kvm_sregs = NULL;
|
|
|
|
if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_dead)
|
|
return -EIO;
|
|
|
|
if (unlikely(_IOC_TYPE(ioctl) != KVMIO))
|
|
return -EINVAL;
|
|
|
|
/*
|
|
* Some architectures have vcpu ioctls that are asynchronous to vcpu
|
|
* execution; mutex_lock() would break them.
|
|
*/
|
|
r = kvm_arch_vcpu_async_ioctl(filp, ioctl, arg);
|
|
if (r != -ENOIOCTLCMD)
|
|
return r;
|
|
|
|
if (mutex_lock_killable(&vcpu->mutex))
|
|
return -EINTR;
|
|
switch (ioctl) {
|
|
case KVM_RUN: {
|
|
struct pid *oldpid;
|
|
r = -EINVAL;
|
|
if (arg)
|
|
goto out;
|
|
oldpid = rcu_access_pointer(vcpu->pid);
|
|
if (unlikely(oldpid != task_pid(current))) {
|
|
/* The thread running this VCPU changed. */
|
|
struct pid *newpid;
|
|
|
|
r = kvm_arch_vcpu_run_pid_change(vcpu);
|
|
if (r)
|
|
break;
|
|
|
|
newpid = get_task_pid(current, PIDTYPE_PID);
|
|
rcu_assign_pointer(vcpu->pid, newpid);
|
|
if (oldpid)
|
|
synchronize_rcu();
|
|
put_pid(oldpid);
|
|
}
|
|
r = kvm_arch_vcpu_ioctl_run(vcpu);
|
|
trace_kvm_userspace_exit(vcpu->run->exit_reason, r);
|
|
break;
|
|
}
|
|
case KVM_GET_REGS: {
|
|
struct kvm_regs *kvm_regs;
|
|
|
|
r = -ENOMEM;
|
|
kvm_regs = kzalloc(sizeof(struct kvm_regs), GFP_KERNEL_ACCOUNT);
|
|
if (!kvm_regs)
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_get_regs(vcpu, kvm_regs);
|
|
if (r)
|
|
goto out_free1;
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, kvm_regs, sizeof(struct kvm_regs)))
|
|
goto out_free1;
|
|
r = 0;
|
|
out_free1:
|
|
kfree(kvm_regs);
|
|
break;
|
|
}
|
|
case KVM_SET_REGS: {
|
|
struct kvm_regs *kvm_regs;
|
|
|
|
kvm_regs = memdup_user(argp, sizeof(*kvm_regs));
|
|
if (IS_ERR(kvm_regs)) {
|
|
r = PTR_ERR(kvm_regs);
|
|
goto out;
|
|
}
|
|
r = kvm_arch_vcpu_ioctl_set_regs(vcpu, kvm_regs);
|
|
kfree(kvm_regs);
|
|
break;
|
|
}
|
|
case KVM_GET_SREGS: {
|
|
kvm_sregs = kzalloc(sizeof(struct kvm_sregs),
|
|
GFP_KERNEL_ACCOUNT);
|
|
r = -ENOMEM;
|
|
if (!kvm_sregs)
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_get_sregs(vcpu, kvm_sregs);
|
|
if (r)
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, kvm_sregs, sizeof(struct kvm_sregs)))
|
|
goto out;
|
|
r = 0;
|
|
break;
|
|
}
|
|
case KVM_SET_SREGS: {
|
|
kvm_sregs = memdup_user(argp, sizeof(*kvm_sregs));
|
|
if (IS_ERR(kvm_sregs)) {
|
|
r = PTR_ERR(kvm_sregs);
|
|
kvm_sregs = NULL;
|
|
goto out;
|
|
}
|
|
r = kvm_arch_vcpu_ioctl_set_sregs(vcpu, kvm_sregs);
|
|
break;
|
|
}
|
|
case KVM_GET_MP_STATE: {
|
|
struct kvm_mp_state mp_state;
|
|
|
|
r = kvm_arch_vcpu_ioctl_get_mpstate(vcpu, &mp_state);
|
|
if (r)
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, &mp_state, sizeof(mp_state)))
|
|
goto out;
|
|
r = 0;
|
|
break;
|
|
}
|
|
case KVM_SET_MP_STATE: {
|
|
struct kvm_mp_state mp_state;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&mp_state, argp, sizeof(mp_state)))
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_set_mpstate(vcpu, &mp_state);
|
|
break;
|
|
}
|
|
case KVM_TRANSLATE: {
|
|
struct kvm_translation tr;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&tr, argp, sizeof(tr)))
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_translate(vcpu, &tr);
|
|
if (r)
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, &tr, sizeof(tr)))
|
|
goto out;
|
|
r = 0;
|
|
break;
|
|
}
|
|
case KVM_SET_GUEST_DEBUG: {
|
|
struct kvm_guest_debug dbg;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&dbg, argp, sizeof(dbg)))
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_set_guest_debug(vcpu, &dbg);
|
|
break;
|
|
}
|
|
case KVM_SET_SIGNAL_MASK: {
|
|
struct kvm_signal_mask __user *sigmask_arg = argp;
|
|
struct kvm_signal_mask kvm_sigmask;
|
|
sigset_t sigset, *p;
|
|
|
|
p = NULL;
|
|
if (argp) {
|
|
r = -EFAULT;
|
|
if (copy_from_user(&kvm_sigmask, argp,
|
|
sizeof(kvm_sigmask)))
|
|
goto out;
|
|
r = -EINVAL;
|
|
if (kvm_sigmask.len != sizeof(sigset))
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (copy_from_user(&sigset, sigmask_arg->sigset,
|
|
sizeof(sigset)))
|
|
goto out;
|
|
p = &sigset;
|
|
}
|
|
r = kvm_vcpu_ioctl_set_sigmask(vcpu, p);
|
|
break;
|
|
}
|
|
case KVM_GET_FPU: {
|
|
fpu = kzalloc(sizeof(struct kvm_fpu), GFP_KERNEL_ACCOUNT);
|
|
r = -ENOMEM;
|
|
if (!fpu)
|
|
goto out;
|
|
r = kvm_arch_vcpu_ioctl_get_fpu(vcpu, fpu);
|
|
if (r)
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, fpu, sizeof(struct kvm_fpu)))
|
|
goto out;
|
|
r = 0;
|
|
break;
|
|
}
|
|
case KVM_SET_FPU: {
|
|
fpu = memdup_user(argp, sizeof(*fpu));
|
|
if (IS_ERR(fpu)) {
|
|
r = PTR_ERR(fpu);
|
|
fpu = NULL;
|
|
goto out;
|
|
}
|
|
r = kvm_arch_vcpu_ioctl_set_fpu(vcpu, fpu);
|
|
break;
|
|
}
|
|
case KVM_GET_STATS_FD: {
|
|
r = kvm_vcpu_ioctl_get_stats_fd(vcpu);
|
|
break;
|
|
}
|
|
default:
|
|
r = kvm_arch_vcpu_ioctl(filp, ioctl, arg);
|
|
}
|
|
out:
|
|
mutex_unlock(&vcpu->mutex);
|
|
kfree(fpu);
|
|
kfree(kvm_sregs);
|
|
return r;
|
|
}
|
|
|
|
#ifdef CONFIG_KVM_COMPAT
|
|
static long kvm_vcpu_compat_ioctl(struct file *filp,
|
|
unsigned int ioctl, unsigned long arg)
|
|
{
|
|
struct kvm_vcpu *vcpu = filp->private_data;
|
|
void __user *argp = compat_ptr(arg);
|
|
int r;
|
|
|
|
if (vcpu->kvm->mm != current->mm || vcpu->kvm->vm_dead)
|
|
return -EIO;
|
|
|
|
switch (ioctl) {
|
|
case KVM_SET_SIGNAL_MASK: {
|
|
struct kvm_signal_mask __user *sigmask_arg = argp;
|
|
struct kvm_signal_mask kvm_sigmask;
|
|
sigset_t sigset;
|
|
|
|
if (argp) {
|
|
r = -EFAULT;
|
|
if (copy_from_user(&kvm_sigmask, argp,
|
|
sizeof(kvm_sigmask)))
|
|
goto out;
|
|
r = -EINVAL;
|
|
if (kvm_sigmask.len != sizeof(compat_sigset_t))
|
|
goto out;
|
|
r = -EFAULT;
|
|
if (get_compat_sigset(&sigset,
|
|
(compat_sigset_t __user *)sigmask_arg->sigset))
|
|
goto out;
|
|
r = kvm_vcpu_ioctl_set_sigmask(vcpu, &sigset);
|
|
} else
|
|
r = kvm_vcpu_ioctl_set_sigmask(vcpu, NULL);
|
|
break;
|
|
}
|
|
default:
|
|
r = kvm_vcpu_ioctl(filp, ioctl, arg);
|
|
}
|
|
|
|
out:
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
static int kvm_device_mmap(struct file *filp, struct vm_area_struct *vma)
|
|
{
|
|
struct kvm_device *dev = filp->private_data;
|
|
|
|
if (dev->ops->mmap)
|
|
return dev->ops->mmap(dev, vma);
|
|
|
|
return -ENODEV;
|
|
}
|
|
|
|
static int kvm_device_ioctl_attr(struct kvm_device *dev,
|
|
int (*accessor)(struct kvm_device *dev,
|
|
struct kvm_device_attr *attr),
|
|
unsigned long arg)
|
|
{
|
|
struct kvm_device_attr attr;
|
|
|
|
if (!accessor)
|
|
return -EPERM;
|
|
|
|
if (copy_from_user(&attr, (void __user *)arg, sizeof(attr)))
|
|
return -EFAULT;
|
|
|
|
return accessor(dev, &attr);
|
|
}
|
|
|
|
static long kvm_device_ioctl(struct file *filp, unsigned int ioctl,
|
|
unsigned long arg)
|
|
{
|
|
struct kvm_device *dev = filp->private_data;
|
|
|
|
if (dev->kvm->mm != current->mm || dev->kvm->vm_dead)
|
|
return -EIO;
|
|
|
|
switch (ioctl) {
|
|
case KVM_SET_DEVICE_ATTR:
|
|
return kvm_device_ioctl_attr(dev, dev->ops->set_attr, arg);
|
|
case KVM_GET_DEVICE_ATTR:
|
|
return kvm_device_ioctl_attr(dev, dev->ops->get_attr, arg);
|
|
case KVM_HAS_DEVICE_ATTR:
|
|
return kvm_device_ioctl_attr(dev, dev->ops->has_attr, arg);
|
|
default:
|
|
if (dev->ops->ioctl)
|
|
return dev->ops->ioctl(dev, ioctl, arg);
|
|
|
|
return -ENOTTY;
|
|
}
|
|
}
|
|
|
|
static int kvm_device_release(struct inode *inode, struct file *filp)
|
|
{
|
|
struct kvm_device *dev = filp->private_data;
|
|
struct kvm *kvm = dev->kvm;
|
|
|
|
if (dev->ops->release) {
|
|
mutex_lock(&kvm->lock);
|
|
list_del(&dev->vm_node);
|
|
dev->ops->release(dev);
|
|
mutex_unlock(&kvm->lock);
|
|
}
|
|
|
|
kvm_put_kvm(kvm);
|
|
return 0;
|
|
}
|
|
|
|
static const struct file_operations kvm_device_fops = {
|
|
.unlocked_ioctl = kvm_device_ioctl,
|
|
.release = kvm_device_release,
|
|
KVM_COMPAT(kvm_device_ioctl),
|
|
.mmap = kvm_device_mmap,
|
|
};
|
|
|
|
struct kvm_device *kvm_device_from_filp(struct file *filp)
|
|
{
|
|
if (filp->f_op != &kvm_device_fops)
|
|
return NULL;
|
|
|
|
return filp->private_data;
|
|
}
|
|
|
|
static const struct kvm_device_ops *kvm_device_ops_table[KVM_DEV_TYPE_MAX] = {
|
|
#ifdef CONFIG_KVM_MPIC
|
|
[KVM_DEV_TYPE_FSL_MPIC_20] = &kvm_mpic_ops,
|
|
[KVM_DEV_TYPE_FSL_MPIC_42] = &kvm_mpic_ops,
|
|
#endif
|
|
};
|
|
|
|
int kvm_register_device_ops(const struct kvm_device_ops *ops, u32 type)
|
|
{
|
|
if (type >= ARRAY_SIZE(kvm_device_ops_table))
|
|
return -ENOSPC;
|
|
|
|
if (kvm_device_ops_table[type] != NULL)
|
|
return -EEXIST;
|
|
|
|
kvm_device_ops_table[type] = ops;
|
|
return 0;
|
|
}
|
|
|
|
void kvm_unregister_device_ops(u32 type)
|
|
{
|
|
if (kvm_device_ops_table[type] != NULL)
|
|
kvm_device_ops_table[type] = NULL;
|
|
}
|
|
|
|
static int kvm_ioctl_create_device(struct kvm *kvm,
|
|
struct kvm_create_device *cd)
|
|
{
|
|
const struct kvm_device_ops *ops;
|
|
struct kvm_device *dev;
|
|
bool test = cd->flags & KVM_CREATE_DEVICE_TEST;
|
|
int type;
|
|
int ret;
|
|
|
|
if (cd->type >= ARRAY_SIZE(kvm_device_ops_table))
|
|
return -ENODEV;
|
|
|
|
type = array_index_nospec(cd->type, ARRAY_SIZE(kvm_device_ops_table));
|
|
ops = kvm_device_ops_table[type];
|
|
if (ops == NULL)
|
|
return -ENODEV;
|
|
|
|
if (test)
|
|
return 0;
|
|
|
|
dev = kzalloc(sizeof(*dev), GFP_KERNEL_ACCOUNT);
|
|
if (!dev)
|
|
return -ENOMEM;
|
|
|
|
dev->ops = ops;
|
|
dev->kvm = kvm;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
ret = ops->create(dev, type);
|
|
if (ret < 0) {
|
|
mutex_unlock(&kvm->lock);
|
|
kfree(dev);
|
|
return ret;
|
|
}
|
|
list_add(&dev->vm_node, &kvm->devices);
|
|
mutex_unlock(&kvm->lock);
|
|
|
|
if (ops->init)
|
|
ops->init(dev);
|
|
|
|
kvm_get_kvm(kvm);
|
|
ret = anon_inode_getfd(ops->name, &kvm_device_fops, dev, O_RDWR | O_CLOEXEC);
|
|
if (ret < 0) {
|
|
kvm_put_kvm_no_destroy(kvm);
|
|
mutex_lock(&kvm->lock);
|
|
list_del(&dev->vm_node);
|
|
if (ops->release)
|
|
ops->release(dev);
|
|
mutex_unlock(&kvm->lock);
|
|
if (ops->destroy)
|
|
ops->destroy(dev);
|
|
return ret;
|
|
}
|
|
|
|
cd->fd = ret;
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg)
|
|
{
|
|
switch (arg) {
|
|
case KVM_CAP_USER_MEMORY:
|
|
case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
|
|
case KVM_CAP_JOIN_MEMORY_REGIONS_WORKS:
|
|
case KVM_CAP_INTERNAL_ERROR_DATA:
|
|
#ifdef CONFIG_HAVE_KVM_MSI
|
|
case KVM_CAP_SIGNAL_MSI:
|
|
#endif
|
|
#ifdef CONFIG_HAVE_KVM_IRQFD
|
|
case KVM_CAP_IRQFD:
|
|
#endif
|
|
case KVM_CAP_IOEVENTFD_ANY_LENGTH:
|
|
case KVM_CAP_CHECK_EXTENSION_VM:
|
|
case KVM_CAP_ENABLE_CAP_VM:
|
|
case KVM_CAP_HALT_POLL:
|
|
return 1;
|
|
#ifdef CONFIG_KVM_MMIO
|
|
case KVM_CAP_COALESCED_MMIO:
|
|
return KVM_COALESCED_MMIO_PAGE_OFFSET;
|
|
case KVM_CAP_COALESCED_PIO:
|
|
return 1;
|
|
#endif
|
|
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
|
|
case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2:
|
|
return KVM_DIRTY_LOG_MANUAL_CAPS;
|
|
#endif
|
|
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
|
|
case KVM_CAP_IRQ_ROUTING:
|
|
return KVM_MAX_IRQ_ROUTES;
|
|
#endif
|
|
#if KVM_ADDRESS_SPACE_NUM > 1
|
|
case KVM_CAP_MULTI_ADDRESS_SPACE:
|
|
return KVM_ADDRESS_SPACE_NUM;
|
|
#endif
|
|
case KVM_CAP_NR_MEMSLOTS:
|
|
return KVM_USER_MEM_SLOTS;
|
|
case KVM_CAP_DIRTY_LOG_RING:
|
|
#ifdef CONFIG_HAVE_KVM_DIRTY_RING_TSO
|
|
return KVM_DIRTY_RING_MAX_ENTRIES * sizeof(struct kvm_dirty_gfn);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
case KVM_CAP_DIRTY_LOG_RING_ACQ_REL:
|
|
#ifdef CONFIG_HAVE_KVM_DIRTY_RING_ACQ_REL
|
|
return KVM_DIRTY_RING_MAX_ENTRIES * sizeof(struct kvm_dirty_gfn);
|
|
#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;
|
|
default:
|
|
break;
|
|
}
|
|
return kvm_vm_ioctl_check_extension(kvm, arg);
|
|
}
|
|
|
|
static int kvm_vm_ioctl_enable_dirty_log_ring(struct kvm *kvm, u32 size)
|
|
{
|
|
int r;
|
|
|
|
if (!KVM_DIRTY_LOG_PAGE_OFFSET)
|
|
return -EINVAL;
|
|
|
|
/* the size should be power of 2 */
|
|
if (!size || (size & (size - 1)))
|
|
return -EINVAL;
|
|
|
|
/* Should be bigger to keep the reserved entries, or a page */
|
|
if (size < kvm_dirty_ring_get_rsvd_entries() *
|
|
sizeof(struct kvm_dirty_gfn) || size < PAGE_SIZE)
|
|
return -EINVAL;
|
|
|
|
if (size > KVM_DIRTY_RING_MAX_ENTRIES *
|
|
sizeof(struct kvm_dirty_gfn))
|
|
return -E2BIG;
|
|
|
|
/* We only allow it to set once */
|
|
if (kvm->dirty_ring_size)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm->lock);
|
|
|
|
if (kvm->created_vcpus) {
|
|
/* We don't allow to change this value after vcpu created */
|
|
r = -EINVAL;
|
|
} else {
|
|
kvm->dirty_ring_size = size;
|
|
r = 0;
|
|
}
|
|
|
|
mutex_unlock(&kvm->lock);
|
|
return r;
|
|
}
|
|
|
|
static int kvm_vm_ioctl_reset_dirty_pages(struct kvm *kvm)
|
|
{
|
|
unsigned long i;
|
|
struct kvm_vcpu *vcpu;
|
|
int cleared = 0;
|
|
|
|
if (!kvm->dirty_ring_size)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm->slots_lock);
|
|
|
|
kvm_for_each_vcpu(i, vcpu, kvm)
|
|
cleared += kvm_dirty_ring_reset(vcpu->kvm, &vcpu->dirty_ring);
|
|
|
|
mutex_unlock(&kvm->slots_lock);
|
|
|
|
if (cleared)
|
|
kvm_flush_remote_tlbs(kvm);
|
|
|
|
return cleared;
|
|
}
|
|
|
|
int __attribute__((weak)) kvm_vm_ioctl_enable_cap(struct kvm *kvm,
|
|
struct kvm_enable_cap *cap)
|
|
{
|
|
return -EINVAL;
|
|
}
|
|
|
|
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;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_are_all_memslots_empty);
|
|
|
|
static int kvm_vm_ioctl_enable_cap_generic(struct kvm *kvm,
|
|
struct kvm_enable_cap *cap)
|
|
{
|
|
switch (cap->cap) {
|
|
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
|
|
case KVM_CAP_MANUAL_DIRTY_LOG_PROTECT2: {
|
|
u64 allowed_options = KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE;
|
|
|
|
if (cap->args[0] & KVM_DIRTY_LOG_MANUAL_PROTECT_ENABLE)
|
|
allowed_options = KVM_DIRTY_LOG_MANUAL_CAPS;
|
|
|
|
if (cap->flags || (cap->args[0] & ~allowed_options))
|
|
return -EINVAL;
|
|
kvm->manual_dirty_log_protect = cap->args[0];
|
|
return 0;
|
|
}
|
|
#endif
|
|
case KVM_CAP_HALT_POLL: {
|
|
if (cap->flags || cap->args[0] != (unsigned int)cap->args[0])
|
|
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:
|
|
case KVM_CAP_DIRTY_LOG_RING_ACQ_REL:
|
|
if (!kvm_vm_ioctl_check_extension_generic(kvm, cap->cap))
|
|
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);
|
|
}
|
|
}
|
|
|
|
static ssize_t kvm_vm_stats_read(struct file *file, char __user *user_buffer,
|
|
size_t size, loff_t *offset)
|
|
{
|
|
struct kvm *kvm = file->private_data;
|
|
|
|
return kvm_stats_read(kvm->stats_id, &kvm_vm_stats_header,
|
|
&kvm_vm_stats_desc[0], &kvm->stat,
|
|
sizeof(kvm->stat), user_buffer, size, offset);
|
|
}
|
|
|
|
static const struct file_operations kvm_vm_stats_fops = {
|
|
.read = kvm_vm_stats_read,
|
|
.llseek = noop_llseek,
|
|
};
|
|
|
|
static int kvm_vm_ioctl_get_stats_fd(struct kvm *kvm)
|
|
{
|
|
int fd;
|
|
struct file *file;
|
|
|
|
fd = get_unused_fd_flags(O_CLOEXEC);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
file = anon_inode_getfile("kvm-vm-stats",
|
|
&kvm_vm_stats_fops, kvm, O_RDONLY);
|
|
if (IS_ERR(file)) {
|
|
put_unused_fd(fd);
|
|
return PTR_ERR(file);
|
|
}
|
|
file->f_mode |= FMODE_PREAD;
|
|
fd_install(fd, file);
|
|
|
|
return fd;
|
|
}
|
|
|
|
static long kvm_vm_ioctl(struct file *filp,
|
|
unsigned int ioctl, unsigned long arg)
|
|
{
|
|
struct kvm *kvm = filp->private_data;
|
|
void __user *argp = (void __user *)arg;
|
|
int r;
|
|
|
|
if (kvm->mm != current->mm || kvm->vm_dead)
|
|
return -EIO;
|
|
switch (ioctl) {
|
|
case KVM_CREATE_VCPU:
|
|
r = kvm_vm_ioctl_create_vcpu(kvm, arg);
|
|
break;
|
|
case KVM_ENABLE_CAP: {
|
|
struct kvm_enable_cap cap;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&cap, argp, sizeof(cap)))
|
|
goto out;
|
|
r = kvm_vm_ioctl_enable_cap_generic(kvm, &cap);
|
|
break;
|
|
}
|
|
case KVM_SET_USER_MEMORY_REGION: {
|
|
struct kvm_userspace_memory_region kvm_userspace_mem;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&kvm_userspace_mem, argp,
|
|
sizeof(kvm_userspace_mem)))
|
|
goto out;
|
|
|
|
r = kvm_vm_ioctl_set_memory_region(kvm, &kvm_userspace_mem);
|
|
break;
|
|
}
|
|
case KVM_GET_DIRTY_LOG: {
|
|
struct kvm_dirty_log log;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&log, argp, sizeof(log)))
|
|
goto out;
|
|
r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
|
|
break;
|
|
}
|
|
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
|
|
case KVM_CLEAR_DIRTY_LOG: {
|
|
struct kvm_clear_dirty_log log;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&log, argp, sizeof(log)))
|
|
goto out;
|
|
r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
|
|
break;
|
|
}
|
|
#endif
|
|
#ifdef CONFIG_KVM_MMIO
|
|
case KVM_REGISTER_COALESCED_MMIO: {
|
|
struct kvm_coalesced_mmio_zone zone;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&zone, argp, sizeof(zone)))
|
|
goto out;
|
|
r = kvm_vm_ioctl_register_coalesced_mmio(kvm, &zone);
|
|
break;
|
|
}
|
|
case KVM_UNREGISTER_COALESCED_MMIO: {
|
|
struct kvm_coalesced_mmio_zone zone;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&zone, argp, sizeof(zone)))
|
|
goto out;
|
|
r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone);
|
|
break;
|
|
}
|
|
#endif
|
|
case KVM_IRQFD: {
|
|
struct kvm_irqfd data;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&data, argp, sizeof(data)))
|
|
goto out;
|
|
r = kvm_irqfd(kvm, &data);
|
|
break;
|
|
}
|
|
case KVM_IOEVENTFD: {
|
|
struct kvm_ioeventfd data;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&data, argp, sizeof(data)))
|
|
goto out;
|
|
r = kvm_ioeventfd(kvm, &data);
|
|
break;
|
|
}
|
|
#ifdef CONFIG_HAVE_KVM_MSI
|
|
case KVM_SIGNAL_MSI: {
|
|
struct kvm_msi msi;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&msi, argp, sizeof(msi)))
|
|
goto out;
|
|
r = kvm_send_userspace_msi(kvm, &msi);
|
|
break;
|
|
}
|
|
#endif
|
|
#ifdef __KVM_HAVE_IRQ_LINE
|
|
case KVM_IRQ_LINE_STATUS:
|
|
case KVM_IRQ_LINE: {
|
|
struct kvm_irq_level irq_event;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&irq_event, argp, sizeof(irq_event)))
|
|
goto out;
|
|
|
|
r = kvm_vm_ioctl_irq_line(kvm, &irq_event,
|
|
ioctl == KVM_IRQ_LINE_STATUS);
|
|
if (r)
|
|
goto out;
|
|
|
|
r = -EFAULT;
|
|
if (ioctl == KVM_IRQ_LINE_STATUS) {
|
|
if (copy_to_user(argp, &irq_event, sizeof(irq_event)))
|
|
goto out;
|
|
}
|
|
|
|
r = 0;
|
|
break;
|
|
}
|
|
#endif
|
|
#ifdef CONFIG_HAVE_KVM_IRQ_ROUTING
|
|
case KVM_SET_GSI_ROUTING: {
|
|
struct kvm_irq_routing routing;
|
|
struct kvm_irq_routing __user *urouting;
|
|
struct kvm_irq_routing_entry *entries = NULL;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&routing, argp, sizeof(routing)))
|
|
goto out;
|
|
r = -EINVAL;
|
|
if (!kvm_arch_can_set_irq_routing(kvm))
|
|
goto out;
|
|
if (routing.nr > KVM_MAX_IRQ_ROUTES)
|
|
goto out;
|
|
if (routing.flags)
|
|
goto out;
|
|
if (routing.nr) {
|
|
urouting = argp;
|
|
entries = vmemdup_user(urouting->entries,
|
|
array_size(sizeof(*entries),
|
|
routing.nr));
|
|
if (IS_ERR(entries)) {
|
|
r = PTR_ERR(entries);
|
|
goto out;
|
|
}
|
|
}
|
|
r = kvm_set_irq_routing(kvm, entries, routing.nr,
|
|
routing.flags);
|
|
kvfree(entries);
|
|
break;
|
|
}
|
|
#endif /* CONFIG_HAVE_KVM_IRQ_ROUTING */
|
|
case KVM_CREATE_DEVICE: {
|
|
struct kvm_create_device cd;
|
|
|
|
r = -EFAULT;
|
|
if (copy_from_user(&cd, argp, sizeof(cd)))
|
|
goto out;
|
|
|
|
r = kvm_ioctl_create_device(kvm, &cd);
|
|
if (r)
|
|
goto out;
|
|
|
|
r = -EFAULT;
|
|
if (copy_to_user(argp, &cd, sizeof(cd)))
|
|
goto out;
|
|
|
|
r = 0;
|
|
break;
|
|
}
|
|
case KVM_CHECK_EXTENSION:
|
|
r = kvm_vm_ioctl_check_extension_generic(kvm, arg);
|
|
break;
|
|
case KVM_RESET_DIRTY_RINGS:
|
|
r = kvm_vm_ioctl_reset_dirty_pages(kvm);
|
|
break;
|
|
case KVM_GET_STATS_FD:
|
|
r = kvm_vm_ioctl_get_stats_fd(kvm);
|
|
break;
|
|
default:
|
|
r = kvm_arch_vm_ioctl(filp, ioctl, arg);
|
|
}
|
|
out:
|
|
return r;
|
|
}
|
|
|
|
#ifdef CONFIG_KVM_COMPAT
|
|
struct compat_kvm_dirty_log {
|
|
__u32 slot;
|
|
__u32 padding1;
|
|
union {
|
|
compat_uptr_t dirty_bitmap; /* one bit per page */
|
|
__u64 padding2;
|
|
};
|
|
};
|
|
|
|
struct compat_kvm_clear_dirty_log {
|
|
__u32 slot;
|
|
__u32 num_pages;
|
|
__u64 first_page;
|
|
union {
|
|
compat_uptr_t dirty_bitmap; /* one bit per page */
|
|
__u64 padding2;
|
|
};
|
|
};
|
|
|
|
long __weak kvm_arch_vm_compat_ioctl(struct file *filp, unsigned int ioctl,
|
|
unsigned long arg)
|
|
{
|
|
return -ENOTTY;
|
|
}
|
|
|
|
static long kvm_vm_compat_ioctl(struct file *filp,
|
|
unsigned int ioctl, unsigned long arg)
|
|
{
|
|
struct kvm *kvm = filp->private_data;
|
|
int r;
|
|
|
|
if (kvm->mm != current->mm || kvm->vm_dead)
|
|
return -EIO;
|
|
|
|
r = kvm_arch_vm_compat_ioctl(filp, ioctl, arg);
|
|
if (r != -ENOTTY)
|
|
return r;
|
|
|
|
switch (ioctl) {
|
|
#ifdef CONFIG_KVM_GENERIC_DIRTYLOG_READ_PROTECT
|
|
case KVM_CLEAR_DIRTY_LOG: {
|
|
struct compat_kvm_clear_dirty_log compat_log;
|
|
struct kvm_clear_dirty_log log;
|
|
|
|
if (copy_from_user(&compat_log, (void __user *)arg,
|
|
sizeof(compat_log)))
|
|
return -EFAULT;
|
|
log.slot = compat_log.slot;
|
|
log.num_pages = compat_log.num_pages;
|
|
log.first_page = compat_log.first_page;
|
|
log.padding2 = compat_log.padding2;
|
|
log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
|
|
|
|
r = kvm_vm_ioctl_clear_dirty_log(kvm, &log);
|
|
break;
|
|
}
|
|
#endif
|
|
case KVM_GET_DIRTY_LOG: {
|
|
struct compat_kvm_dirty_log compat_log;
|
|
struct kvm_dirty_log log;
|
|
|
|
if (copy_from_user(&compat_log, (void __user *)arg,
|
|
sizeof(compat_log)))
|
|
return -EFAULT;
|
|
log.slot = compat_log.slot;
|
|
log.padding1 = compat_log.padding1;
|
|
log.padding2 = compat_log.padding2;
|
|
log.dirty_bitmap = compat_ptr(compat_log.dirty_bitmap);
|
|
|
|
r = kvm_vm_ioctl_get_dirty_log(kvm, &log);
|
|
break;
|
|
}
|
|
default:
|
|
r = kvm_vm_ioctl(filp, ioctl, arg);
|
|
}
|
|
return r;
|
|
}
|
|
#endif
|
|
|
|
static const struct file_operations kvm_vm_fops = {
|
|
.release = kvm_vm_release,
|
|
.unlocked_ioctl = kvm_vm_ioctl,
|
|
.llseek = noop_llseek,
|
|
KVM_COMPAT(kvm_vm_compat_ioctl),
|
|
};
|
|
|
|
bool file_is_kvm(struct file *file)
|
|
{
|
|
return file && file->f_op == &kvm_vm_fops;
|
|
}
|
|
EXPORT_SYMBOL_GPL(file_is_kvm);
|
|
|
|
static int kvm_dev_ioctl_create_vm(unsigned long type)
|
|
{
|
|
char fdname[ITOA_MAX_LEN + 1];
|
|
int r, fd;
|
|
struct kvm *kvm;
|
|
struct file *file;
|
|
|
|
fd = get_unused_fd_flags(O_CLOEXEC);
|
|
if (fd < 0)
|
|
return fd;
|
|
|
|
snprintf(fdname, sizeof(fdname), "%d", fd);
|
|
|
|
kvm = kvm_create_vm(type, fdname);
|
|
if (IS_ERR(kvm)) {
|
|
r = PTR_ERR(kvm);
|
|
goto put_fd;
|
|
}
|
|
|
|
file = anon_inode_getfile("kvm-vm", &kvm_vm_fops, kvm, O_RDWR);
|
|
if (IS_ERR(file)) {
|
|
r = PTR_ERR(file);
|
|
goto put_kvm;
|
|
}
|
|
|
|
/*
|
|
* Don't call kvm_put_kvm anymore at this point; file->f_op is
|
|
* already set, with ->release() being kvm_vm_release(). In error
|
|
* cases it will be called by the final fput(file) and will take
|
|
* care of doing kvm_put_kvm(kvm).
|
|
*/
|
|
kvm_uevent_notify_change(KVM_EVENT_CREATE_VM, kvm);
|
|
|
|
fd_install(fd, file);
|
|
return fd;
|
|
|
|
put_kvm:
|
|
kvm_put_kvm(kvm);
|
|
put_fd:
|
|
put_unused_fd(fd);
|
|
return r;
|
|
}
|
|
|
|
static long kvm_dev_ioctl(struct file *filp,
|
|
unsigned int ioctl, unsigned long arg)
|
|
{
|
|
int r = -EINVAL;
|
|
|
|
switch (ioctl) {
|
|
case KVM_GET_API_VERSION:
|
|
if (arg)
|
|
goto out;
|
|
r = KVM_API_VERSION;
|
|
break;
|
|
case KVM_CREATE_VM:
|
|
r = kvm_dev_ioctl_create_vm(arg);
|
|
break;
|
|
case KVM_CHECK_EXTENSION:
|
|
r = kvm_vm_ioctl_check_extension_generic(NULL, arg);
|
|
break;
|
|
case KVM_GET_VCPU_MMAP_SIZE:
|
|
if (arg)
|
|
goto out;
|
|
r = PAGE_SIZE; /* struct kvm_run */
|
|
#ifdef CONFIG_X86
|
|
r += PAGE_SIZE; /* pio data page */
|
|
#endif
|
|
#ifdef CONFIG_KVM_MMIO
|
|
r += PAGE_SIZE; /* coalesced mmio ring page */
|
|
#endif
|
|
break;
|
|
case KVM_TRACE_ENABLE:
|
|
case KVM_TRACE_PAUSE:
|
|
case KVM_TRACE_DISABLE:
|
|
r = -EOPNOTSUPP;
|
|
break;
|
|
default:
|
|
return kvm_arch_dev_ioctl(filp, ioctl, arg);
|
|
}
|
|
out:
|
|
return r;
|
|
}
|
|
|
|
static struct file_operations kvm_chardev_ops = {
|
|
.unlocked_ioctl = kvm_dev_ioctl,
|
|
.llseek = noop_llseek,
|
|
KVM_COMPAT(kvm_dev_ioctl),
|
|
};
|
|
|
|
static struct miscdevice kvm_dev = {
|
|
KVM_MINOR,
|
|
"kvm",
|
|
&kvm_chardev_ops,
|
|
};
|
|
|
|
#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING
|
|
__visible bool kvm_rebooting;
|
|
EXPORT_SYMBOL_GPL(kvm_rebooting);
|
|
|
|
static DEFINE_PER_CPU(bool, hardware_enabled);
|
|
static int kvm_usage_count;
|
|
|
|
static int __hardware_enable_nolock(void)
|
|
{
|
|
if (__this_cpu_read(hardware_enabled))
|
|
return 0;
|
|
|
|
if (kvm_arch_hardware_enable()) {
|
|
pr_info("kvm: enabling virtualization on CPU%d failed\n",
|
|
raw_smp_processor_id());
|
|
return -EIO;
|
|
}
|
|
|
|
__this_cpu_write(hardware_enabled, true);
|
|
return 0;
|
|
}
|
|
|
|
static void hardware_enable_nolock(void *failed)
|
|
{
|
|
if (__hardware_enable_nolock())
|
|
atomic_inc(failed);
|
|
}
|
|
|
|
static int kvm_online_cpu(unsigned int cpu)
|
|
{
|
|
int ret = 0;
|
|
|
|
/*
|
|
* Abort the CPU online process if hardware virtualization cannot
|
|
* be enabled. Otherwise running VMs would encounter unrecoverable
|
|
* errors when scheduled to this CPU.
|
|
*/
|
|
mutex_lock(&kvm_lock);
|
|
if (kvm_usage_count)
|
|
ret = __hardware_enable_nolock();
|
|
mutex_unlock(&kvm_lock);
|
|
return ret;
|
|
}
|
|
|
|
static void hardware_disable_nolock(void *junk)
|
|
{
|
|
/*
|
|
* Note, hardware_disable_all_nolock() tells all online CPUs to disable
|
|
* hardware, not just CPUs that successfully enabled hardware!
|
|
*/
|
|
if (!__this_cpu_read(hardware_enabled))
|
|
return;
|
|
|
|
kvm_arch_hardware_disable();
|
|
|
|
__this_cpu_write(hardware_enabled, false);
|
|
}
|
|
|
|
static int kvm_offline_cpu(unsigned int cpu)
|
|
{
|
|
mutex_lock(&kvm_lock);
|
|
if (kvm_usage_count)
|
|
hardware_disable_nolock(NULL);
|
|
mutex_unlock(&kvm_lock);
|
|
return 0;
|
|
}
|
|
|
|
static void hardware_disable_all_nolock(void)
|
|
{
|
|
BUG_ON(!kvm_usage_count);
|
|
|
|
kvm_usage_count--;
|
|
if (!kvm_usage_count)
|
|
on_each_cpu(hardware_disable_nolock, NULL, 1);
|
|
}
|
|
|
|
static void hardware_disable_all(void)
|
|
{
|
|
cpus_read_lock();
|
|
mutex_lock(&kvm_lock);
|
|
hardware_disable_all_nolock();
|
|
mutex_unlock(&kvm_lock);
|
|
cpus_read_unlock();
|
|
}
|
|
|
|
static int hardware_enable_all(void)
|
|
{
|
|
atomic_t failed = ATOMIC_INIT(0);
|
|
int r;
|
|
|
|
/*
|
|
* Do not enable hardware virtualization if the system is going down.
|
|
* If userspace initiated a forced reboot, e.g. reboot -f, then it's
|
|
* possible for an in-flight KVM_CREATE_VM to trigger hardware enabling
|
|
* after kvm_reboot() is called. Note, this relies on system_state
|
|
* being set _before_ kvm_reboot(), which is why KVM uses a syscore ops
|
|
* hook instead of registering a dedicated reboot notifier (the latter
|
|
* runs before system_state is updated).
|
|
*/
|
|
if (system_state == SYSTEM_HALT || system_state == SYSTEM_POWER_OFF ||
|
|
system_state == SYSTEM_RESTART)
|
|
return -EBUSY;
|
|
|
|
/*
|
|
* When onlining a CPU, cpu_online_mask is set before kvm_online_cpu()
|
|
* is called, and so on_each_cpu() between them includes the CPU that
|
|
* is being onlined. As a result, hardware_enable_nolock() may get
|
|
* invoked before kvm_online_cpu(), which also enables hardware if the
|
|
* usage count is non-zero. Disable CPU hotplug to avoid attempting to
|
|
* enable hardware multiple times.
|
|
*/
|
|
cpus_read_lock();
|
|
mutex_lock(&kvm_lock);
|
|
|
|
r = 0;
|
|
|
|
kvm_usage_count++;
|
|
if (kvm_usage_count == 1) {
|
|
on_each_cpu(hardware_enable_nolock, &failed, 1);
|
|
|
|
if (atomic_read(&failed)) {
|
|
hardware_disable_all_nolock();
|
|
r = -EBUSY;
|
|
}
|
|
}
|
|
|
|
mutex_unlock(&kvm_lock);
|
|
cpus_read_unlock();
|
|
|
|
return r;
|
|
}
|
|
|
|
static void kvm_shutdown(void)
|
|
{
|
|
/*
|
|
* Disable hardware virtualization and set kvm_rebooting to indicate
|
|
* that KVM has asynchronously disabled hardware virtualization, i.e.
|
|
* that relevant errors and exceptions aren't entirely unexpected.
|
|
* Some flavors of hardware virtualization need to be disabled before
|
|
* transferring control to firmware (to perform shutdown/reboot), e.g.
|
|
* on x86, virtualization can block INIT interrupts, which are used by
|
|
* firmware to pull APs back under firmware control. Note, this path
|
|
* is used for both shutdown and reboot scenarios, i.e. neither name is
|
|
* 100% comprehensive.
|
|
*/
|
|
pr_info("kvm: exiting hardware virtualization\n");
|
|
kvm_rebooting = true;
|
|
on_each_cpu(hardware_disable_nolock, NULL, 1);
|
|
}
|
|
|
|
static int kvm_suspend(void)
|
|
{
|
|
/*
|
|
* Secondary CPUs and CPU hotplug are disabled across the suspend/resume
|
|
* callbacks, i.e. no need to acquire kvm_lock to ensure the usage count
|
|
* is stable. Assert that kvm_lock is not held to ensure the system
|
|
* isn't suspended while KVM is enabling hardware. Hardware enabling
|
|
* can be preempted, but the task cannot be frozen until it has dropped
|
|
* all locks (userspace tasks are frozen via a fake signal).
|
|
*/
|
|
lockdep_assert_not_held(&kvm_lock);
|
|
lockdep_assert_irqs_disabled();
|
|
|
|
if (kvm_usage_count)
|
|
hardware_disable_nolock(NULL);
|
|
return 0;
|
|
}
|
|
|
|
static void kvm_resume(void)
|
|
{
|
|
lockdep_assert_not_held(&kvm_lock);
|
|
lockdep_assert_irqs_disabled();
|
|
|
|
if (kvm_usage_count)
|
|
WARN_ON_ONCE(__hardware_enable_nolock());
|
|
}
|
|
|
|
static struct syscore_ops kvm_syscore_ops = {
|
|
.suspend = kvm_suspend,
|
|
.resume = kvm_resume,
|
|
.shutdown = kvm_shutdown,
|
|
};
|
|
#else /* CONFIG_KVM_GENERIC_HARDWARE_ENABLING */
|
|
static int hardware_enable_all(void)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void hardware_disable_all(void)
|
|
{
|
|
|
|
}
|
|
#endif /* CONFIG_KVM_GENERIC_HARDWARE_ENABLING */
|
|
|
|
static void kvm_iodevice_destructor(struct kvm_io_device *dev)
|
|
{
|
|
if (dev->ops->destructor)
|
|
dev->ops->destructor(dev);
|
|
}
|
|
|
|
static void kvm_io_bus_destroy(struct kvm_io_bus *bus)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < bus->dev_count; i++) {
|
|
struct kvm_io_device *pos = bus->range[i].dev;
|
|
|
|
kvm_iodevice_destructor(pos);
|
|
}
|
|
kfree(bus);
|
|
}
|
|
|
|
static inline int kvm_io_bus_cmp(const struct kvm_io_range *r1,
|
|
const struct kvm_io_range *r2)
|
|
{
|
|
gpa_t addr1 = r1->addr;
|
|
gpa_t addr2 = r2->addr;
|
|
|
|
if (addr1 < addr2)
|
|
return -1;
|
|
|
|
/* If r2->len == 0, match the exact address. If r2->len != 0,
|
|
* accept any overlapping write. Any order is acceptable for
|
|
* overlapping ranges, because kvm_io_bus_get_first_dev ensures
|
|
* we process all of them.
|
|
*/
|
|
if (r2->len) {
|
|
addr1 += r1->len;
|
|
addr2 += r2->len;
|
|
}
|
|
|
|
if (addr1 > addr2)
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_io_bus_sort_cmp(const void *p1, const void *p2)
|
|
{
|
|
return kvm_io_bus_cmp(p1, p2);
|
|
}
|
|
|
|
static int kvm_io_bus_get_first_dev(struct kvm_io_bus *bus,
|
|
gpa_t addr, int len)
|
|
{
|
|
struct kvm_io_range *range, key;
|
|
int off;
|
|
|
|
key = (struct kvm_io_range) {
|
|
.addr = addr,
|
|
.len = len,
|
|
};
|
|
|
|
range = bsearch(&key, bus->range, bus->dev_count,
|
|
sizeof(struct kvm_io_range), kvm_io_bus_sort_cmp);
|
|
if (range == NULL)
|
|
return -ENOENT;
|
|
|
|
off = range - bus->range;
|
|
|
|
while (off > 0 && kvm_io_bus_cmp(&key, &bus->range[off-1]) == 0)
|
|
off--;
|
|
|
|
return off;
|
|
}
|
|
|
|
static int __kvm_io_bus_write(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
|
|
struct kvm_io_range *range, const void *val)
|
|
{
|
|
int idx;
|
|
|
|
idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
|
|
if (idx < 0)
|
|
return -EOPNOTSUPP;
|
|
|
|
while (idx < bus->dev_count &&
|
|
kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
|
|
if (!kvm_iodevice_write(vcpu, bus->range[idx].dev, range->addr,
|
|
range->len, val))
|
|
return idx;
|
|
idx++;
|
|
}
|
|
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/* kvm_io_bus_write - called under kvm->slots_lock */
|
|
int kvm_io_bus_write(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
|
|
int len, const void *val)
|
|
{
|
|
struct kvm_io_bus *bus;
|
|
struct kvm_io_range range;
|
|
int r;
|
|
|
|
range = (struct kvm_io_range) {
|
|
.addr = addr,
|
|
.len = len,
|
|
};
|
|
|
|
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
|
|
if (!bus)
|
|
return -ENOMEM;
|
|
r = __kvm_io_bus_write(vcpu, bus, &range, val);
|
|
return r < 0 ? r : 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_io_bus_write);
|
|
|
|
/* kvm_io_bus_write_cookie - called under kvm->slots_lock */
|
|
int kvm_io_bus_write_cookie(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx,
|
|
gpa_t addr, int len, const void *val, long cookie)
|
|
{
|
|
struct kvm_io_bus *bus;
|
|
struct kvm_io_range range;
|
|
|
|
range = (struct kvm_io_range) {
|
|
.addr = addr,
|
|
.len = len,
|
|
};
|
|
|
|
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
|
|
if (!bus)
|
|
return -ENOMEM;
|
|
|
|
/* First try the device referenced by cookie. */
|
|
if ((cookie >= 0) && (cookie < bus->dev_count) &&
|
|
(kvm_io_bus_cmp(&range, &bus->range[cookie]) == 0))
|
|
if (!kvm_iodevice_write(vcpu, bus->range[cookie].dev, addr, len,
|
|
val))
|
|
return cookie;
|
|
|
|
/*
|
|
* cookie contained garbage; fall back to search and return the
|
|
* correct cookie value.
|
|
*/
|
|
return __kvm_io_bus_write(vcpu, bus, &range, val);
|
|
}
|
|
|
|
static int __kvm_io_bus_read(struct kvm_vcpu *vcpu, struct kvm_io_bus *bus,
|
|
struct kvm_io_range *range, void *val)
|
|
{
|
|
int idx;
|
|
|
|
idx = kvm_io_bus_get_first_dev(bus, range->addr, range->len);
|
|
if (idx < 0)
|
|
return -EOPNOTSUPP;
|
|
|
|
while (idx < bus->dev_count &&
|
|
kvm_io_bus_cmp(range, &bus->range[idx]) == 0) {
|
|
if (!kvm_iodevice_read(vcpu, bus->range[idx].dev, range->addr,
|
|
range->len, val))
|
|
return idx;
|
|
idx++;
|
|
}
|
|
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
/* kvm_io_bus_read - called under kvm->slots_lock */
|
|
int kvm_io_bus_read(struct kvm_vcpu *vcpu, enum kvm_bus bus_idx, gpa_t addr,
|
|
int len, void *val)
|
|
{
|
|
struct kvm_io_bus *bus;
|
|
struct kvm_io_range range;
|
|
int r;
|
|
|
|
range = (struct kvm_io_range) {
|
|
.addr = addr,
|
|
.len = len,
|
|
};
|
|
|
|
bus = srcu_dereference(vcpu->kvm->buses[bus_idx], &vcpu->kvm->srcu);
|
|
if (!bus)
|
|
return -ENOMEM;
|
|
r = __kvm_io_bus_read(vcpu, bus, &range, val);
|
|
return r < 0 ? r : 0;
|
|
}
|
|
|
|
/* Caller must hold slots_lock. */
|
|
int kvm_io_bus_register_dev(struct kvm *kvm, enum kvm_bus bus_idx, gpa_t addr,
|
|
int len, struct kvm_io_device *dev)
|
|
{
|
|
int i;
|
|
struct kvm_io_bus *new_bus, *bus;
|
|
struct kvm_io_range range;
|
|
|
|
bus = kvm_get_bus(kvm, bus_idx);
|
|
if (!bus)
|
|
return -ENOMEM;
|
|
|
|
/* exclude ioeventfd which is limited by maximum fd */
|
|
if (bus->dev_count - bus->ioeventfd_count > NR_IOBUS_DEVS - 1)
|
|
return -ENOSPC;
|
|
|
|
new_bus = kmalloc(struct_size(bus, range, bus->dev_count + 1),
|
|
GFP_KERNEL_ACCOUNT);
|
|
if (!new_bus)
|
|
return -ENOMEM;
|
|
|
|
range = (struct kvm_io_range) {
|
|
.addr = addr,
|
|
.len = len,
|
|
.dev = dev,
|
|
};
|
|
|
|
for (i = 0; i < bus->dev_count; i++)
|
|
if (kvm_io_bus_cmp(&bus->range[i], &range) > 0)
|
|
break;
|
|
|
|
memcpy(new_bus, bus, sizeof(*bus) + i * sizeof(struct kvm_io_range));
|
|
new_bus->dev_count++;
|
|
new_bus->range[i] = range;
|
|
memcpy(new_bus->range + i + 1, bus->range + i,
|
|
(bus->dev_count - i) * sizeof(struct kvm_io_range));
|
|
rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
|
|
synchronize_srcu_expedited(&kvm->srcu);
|
|
kfree(bus);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int kvm_io_bus_unregister_dev(struct kvm *kvm, enum kvm_bus bus_idx,
|
|
struct kvm_io_device *dev)
|
|
{
|
|
int i;
|
|
struct kvm_io_bus *new_bus, *bus;
|
|
|
|
lockdep_assert_held(&kvm->slots_lock);
|
|
|
|
bus = kvm_get_bus(kvm, bus_idx);
|
|
if (!bus)
|
|
return 0;
|
|
|
|
for (i = 0; i < bus->dev_count; i++) {
|
|
if (bus->range[i].dev == dev) {
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (i == bus->dev_count)
|
|
return 0;
|
|
|
|
new_bus = kmalloc(struct_size(bus, range, bus->dev_count - 1),
|
|
GFP_KERNEL_ACCOUNT);
|
|
if (new_bus) {
|
|
memcpy(new_bus, bus, struct_size(bus, range, i));
|
|
new_bus->dev_count--;
|
|
memcpy(new_bus->range + i, bus->range + i + 1,
|
|
flex_array_size(new_bus, range, new_bus->dev_count - i));
|
|
}
|
|
|
|
rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
|
|
synchronize_srcu_expedited(&kvm->srcu);
|
|
|
|
/*
|
|
* If NULL bus is installed, destroy the old bus, including all the
|
|
* attached devices. Otherwise, destroy the caller's device only.
|
|
*/
|
|
if (!new_bus) {
|
|
pr_err("kvm: failed to shrink bus, removing it completely\n");
|
|
kvm_io_bus_destroy(bus);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
kvm_iodevice_destructor(dev);
|
|
kfree(bus);
|
|
return 0;
|
|
}
|
|
|
|
struct kvm_io_device *kvm_io_bus_get_dev(struct kvm *kvm, enum kvm_bus bus_idx,
|
|
gpa_t addr)
|
|
{
|
|
struct kvm_io_bus *bus;
|
|
int dev_idx, srcu_idx;
|
|
struct kvm_io_device *iodev = NULL;
|
|
|
|
srcu_idx = srcu_read_lock(&kvm->srcu);
|
|
|
|
bus = srcu_dereference(kvm->buses[bus_idx], &kvm->srcu);
|
|
if (!bus)
|
|
goto out_unlock;
|
|
|
|
dev_idx = kvm_io_bus_get_first_dev(bus, addr, 1);
|
|
if (dev_idx < 0)
|
|
goto out_unlock;
|
|
|
|
iodev = bus->range[dev_idx].dev;
|
|
|
|
out_unlock:
|
|
srcu_read_unlock(&kvm->srcu, srcu_idx);
|
|
|
|
return iodev;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_io_bus_get_dev);
|
|
|
|
static int kvm_debugfs_open(struct inode *inode, struct file *file,
|
|
int (*get)(void *, u64 *), int (*set)(void *, u64),
|
|
const char *fmt)
|
|
{
|
|
int ret;
|
|
struct kvm_stat_data *stat_data = inode->i_private;
|
|
|
|
/*
|
|
* The debugfs files are a reference to the kvm struct which
|
|
* is still valid when kvm_destroy_vm is called. kvm_get_kvm_safe
|
|
* avoids the race between open and the removal of the debugfs directory.
|
|
*/
|
|
if (!kvm_get_kvm_safe(stat_data->kvm))
|
|
return -ENOENT;
|
|
|
|
ret = simple_attr_open(inode, file, get,
|
|
kvm_stats_debugfs_mode(stat_data->desc) & 0222
|
|
? set : NULL, fmt);
|
|
if (ret)
|
|
kvm_put_kvm(stat_data->kvm);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int kvm_debugfs_release(struct inode *inode, struct file *file)
|
|
{
|
|
struct kvm_stat_data *stat_data = inode->i_private;
|
|
|
|
simple_attr_release(inode, file);
|
|
kvm_put_kvm(stat_data->kvm);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_get_stat_per_vm(struct kvm *kvm, size_t offset, u64 *val)
|
|
{
|
|
*val = *(u64 *)((void *)(&kvm->stat) + offset);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_clear_stat_per_vm(struct kvm *kvm, size_t offset)
|
|
{
|
|
*(u64 *)((void *)(&kvm->stat) + offset) = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_get_stat_per_vcpu(struct kvm *kvm, size_t offset, u64 *val)
|
|
{
|
|
unsigned long i;
|
|
struct kvm_vcpu *vcpu;
|
|
|
|
*val = 0;
|
|
|
|
kvm_for_each_vcpu(i, vcpu, kvm)
|
|
*val += *(u64 *)((void *)(&vcpu->stat) + offset);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_clear_stat_per_vcpu(struct kvm *kvm, size_t offset)
|
|
{
|
|
unsigned long i;
|
|
struct kvm_vcpu *vcpu;
|
|
|
|
kvm_for_each_vcpu(i, vcpu, kvm)
|
|
*(u64 *)((void *)(&vcpu->stat) + offset) = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int kvm_stat_data_get(void *data, u64 *val)
|
|
{
|
|
int r = -EFAULT;
|
|
struct kvm_stat_data *stat_data = data;
|
|
|
|
switch (stat_data->kind) {
|
|
case KVM_STAT_VM:
|
|
r = kvm_get_stat_per_vm(stat_data->kvm,
|
|
stat_data->desc->desc.offset, val);
|
|
break;
|
|
case KVM_STAT_VCPU:
|
|
r = kvm_get_stat_per_vcpu(stat_data->kvm,
|
|
stat_data->desc->desc.offset, val);
|
|
break;
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static int kvm_stat_data_clear(void *data, u64 val)
|
|
{
|
|
int r = -EFAULT;
|
|
struct kvm_stat_data *stat_data = data;
|
|
|
|
if (val)
|
|
return -EINVAL;
|
|
|
|
switch (stat_data->kind) {
|
|
case KVM_STAT_VM:
|
|
r = kvm_clear_stat_per_vm(stat_data->kvm,
|
|
stat_data->desc->desc.offset);
|
|
break;
|
|
case KVM_STAT_VCPU:
|
|
r = kvm_clear_stat_per_vcpu(stat_data->kvm,
|
|
stat_data->desc->desc.offset);
|
|
break;
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
static int kvm_stat_data_open(struct inode *inode, struct file *file)
|
|
{
|
|
__simple_attr_check_format("%llu\n", 0ull);
|
|
return kvm_debugfs_open(inode, file, kvm_stat_data_get,
|
|
kvm_stat_data_clear, "%llu\n");
|
|
}
|
|
|
|
static const struct file_operations stat_fops_per_vm = {
|
|
.owner = THIS_MODULE,
|
|
.open = kvm_stat_data_open,
|
|
.release = kvm_debugfs_release,
|
|
.read = simple_attr_read,
|
|
.write = simple_attr_write,
|
|
.llseek = no_llseek,
|
|
};
|
|
|
|
static int vm_stat_get(void *_offset, u64 *val)
|
|
{
|
|
unsigned offset = (long)_offset;
|
|
struct kvm *kvm;
|
|
u64 tmp_val;
|
|
|
|
*val = 0;
|
|
mutex_lock(&kvm_lock);
|
|
list_for_each_entry(kvm, &vm_list, vm_list) {
|
|
kvm_get_stat_per_vm(kvm, offset, &tmp_val);
|
|
*val += tmp_val;
|
|
}
|
|
mutex_unlock(&kvm_lock);
|
|
return 0;
|
|
}
|
|
|
|
static int vm_stat_clear(void *_offset, u64 val)
|
|
{
|
|
unsigned offset = (long)_offset;
|
|
struct kvm *kvm;
|
|
|
|
if (val)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm_lock);
|
|
list_for_each_entry(kvm, &vm_list, vm_list) {
|
|
kvm_clear_stat_per_vm(kvm, offset);
|
|
}
|
|
mutex_unlock(&kvm_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(vm_stat_fops, vm_stat_get, vm_stat_clear, "%llu\n");
|
|
DEFINE_SIMPLE_ATTRIBUTE(vm_stat_readonly_fops, vm_stat_get, NULL, "%llu\n");
|
|
|
|
static int vcpu_stat_get(void *_offset, u64 *val)
|
|
{
|
|
unsigned offset = (long)_offset;
|
|
struct kvm *kvm;
|
|
u64 tmp_val;
|
|
|
|
*val = 0;
|
|
mutex_lock(&kvm_lock);
|
|
list_for_each_entry(kvm, &vm_list, vm_list) {
|
|
kvm_get_stat_per_vcpu(kvm, offset, &tmp_val);
|
|
*val += tmp_val;
|
|
}
|
|
mutex_unlock(&kvm_lock);
|
|
return 0;
|
|
}
|
|
|
|
static int vcpu_stat_clear(void *_offset, u64 val)
|
|
{
|
|
unsigned offset = (long)_offset;
|
|
struct kvm *kvm;
|
|
|
|
if (val)
|
|
return -EINVAL;
|
|
|
|
mutex_lock(&kvm_lock);
|
|
list_for_each_entry(kvm, &vm_list, vm_list) {
|
|
kvm_clear_stat_per_vcpu(kvm, offset);
|
|
}
|
|
mutex_unlock(&kvm_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_fops, vcpu_stat_get, vcpu_stat_clear,
|
|
"%llu\n");
|
|
DEFINE_SIMPLE_ATTRIBUTE(vcpu_stat_readonly_fops, vcpu_stat_get, NULL, "%llu\n");
|
|
|
|
static void kvm_uevent_notify_change(unsigned int type, struct kvm *kvm)
|
|
{
|
|
struct kobj_uevent_env *env;
|
|
unsigned long long created, active;
|
|
|
|
if (!kvm_dev.this_device || !kvm)
|
|
return;
|
|
|
|
mutex_lock(&kvm_lock);
|
|
if (type == KVM_EVENT_CREATE_VM) {
|
|
kvm_createvm_count++;
|
|
kvm_active_vms++;
|
|
} else if (type == KVM_EVENT_DESTROY_VM) {
|
|
kvm_active_vms--;
|
|
}
|
|
created = kvm_createvm_count;
|
|
active = kvm_active_vms;
|
|
mutex_unlock(&kvm_lock);
|
|
|
|
env = kzalloc(sizeof(*env), GFP_KERNEL_ACCOUNT);
|
|
if (!env)
|
|
return;
|
|
|
|
add_uevent_var(env, "CREATED=%llu", created);
|
|
add_uevent_var(env, "COUNT=%llu", active);
|
|
|
|
if (type == KVM_EVENT_CREATE_VM) {
|
|
add_uevent_var(env, "EVENT=create");
|
|
kvm->userspace_pid = task_pid_nr(current);
|
|
} else if (type == KVM_EVENT_DESTROY_VM) {
|
|
add_uevent_var(env, "EVENT=destroy");
|
|
}
|
|
add_uevent_var(env, "PID=%d", kvm->userspace_pid);
|
|
|
|
if (!IS_ERR(kvm->debugfs_dentry)) {
|
|
char *tmp, *p = kmalloc(PATH_MAX, GFP_KERNEL_ACCOUNT);
|
|
|
|
if (p) {
|
|
tmp = dentry_path_raw(kvm->debugfs_dentry, p, PATH_MAX);
|
|
if (!IS_ERR(tmp))
|
|
add_uevent_var(env, "STATS_PATH=%s", tmp);
|
|
kfree(p);
|
|
}
|
|
}
|
|
/* no need for checks, since we are adding at most only 5 keys */
|
|
env->envp[env->envp_idx++] = NULL;
|
|
kobject_uevent_env(&kvm_dev.this_device->kobj, KOBJ_CHANGE, env->envp);
|
|
kfree(env);
|
|
}
|
|
|
|
static void kvm_init_debug(void)
|
|
{
|
|
const struct file_operations *fops;
|
|
const struct _kvm_stats_desc *pdesc;
|
|
int i;
|
|
|
|
kvm_debugfs_dir = debugfs_create_dir("kvm", NULL);
|
|
|
|
for (i = 0; i < kvm_vm_stats_header.num_desc; ++i) {
|
|
pdesc = &kvm_vm_stats_desc[i];
|
|
if (kvm_stats_debugfs_mode(pdesc) & 0222)
|
|
fops = &vm_stat_fops;
|
|
else
|
|
fops = &vm_stat_readonly_fops;
|
|
debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
|
|
kvm_debugfs_dir,
|
|
(void *)(long)pdesc->desc.offset, fops);
|
|
}
|
|
|
|
for (i = 0; i < kvm_vcpu_stats_header.num_desc; ++i) {
|
|
pdesc = &kvm_vcpu_stats_desc[i];
|
|
if (kvm_stats_debugfs_mode(pdesc) & 0222)
|
|
fops = &vcpu_stat_fops;
|
|
else
|
|
fops = &vcpu_stat_readonly_fops;
|
|
debugfs_create_file(pdesc->name, kvm_stats_debugfs_mode(pdesc),
|
|
kvm_debugfs_dir,
|
|
(void *)(long)pdesc->desc.offset, fops);
|
|
}
|
|
}
|
|
|
|
static inline
|
|
struct kvm_vcpu *preempt_notifier_to_vcpu(struct preempt_notifier *pn)
|
|
{
|
|
return container_of(pn, struct kvm_vcpu, preempt_notifier);
|
|
}
|
|
|
|
static void kvm_sched_in(struct preempt_notifier *pn, int cpu)
|
|
{
|
|
struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
|
|
|
|
WRITE_ONCE(vcpu->preempted, false);
|
|
WRITE_ONCE(vcpu->ready, false);
|
|
|
|
__this_cpu_write(kvm_running_vcpu, vcpu);
|
|
kvm_arch_sched_in(vcpu, cpu);
|
|
kvm_arch_vcpu_load(vcpu, cpu);
|
|
}
|
|
|
|
static void kvm_sched_out(struct preempt_notifier *pn,
|
|
struct task_struct *next)
|
|
{
|
|
struct kvm_vcpu *vcpu = preempt_notifier_to_vcpu(pn);
|
|
|
|
if (current->on_rq) {
|
|
WRITE_ONCE(vcpu->preempted, true);
|
|
WRITE_ONCE(vcpu->ready, true);
|
|
}
|
|
kvm_arch_vcpu_put(vcpu);
|
|
__this_cpu_write(kvm_running_vcpu, NULL);
|
|
}
|
|
|
|
/**
|
|
* kvm_get_running_vcpu - get the vcpu running on the current CPU.
|
|
*
|
|
* We can disable preemption locally around accessing the per-CPU variable,
|
|
* and use the resolved vcpu pointer after enabling preemption again,
|
|
* because even if the current thread is migrated to another CPU, reading
|
|
* the per-CPU value later will give us the same value as we update the
|
|
* per-CPU variable in the preempt notifier handlers.
|
|
*/
|
|
struct kvm_vcpu *kvm_get_running_vcpu(void)
|
|
{
|
|
struct kvm_vcpu *vcpu;
|
|
|
|
preempt_disable();
|
|
vcpu = __this_cpu_read(kvm_running_vcpu);
|
|
preempt_enable();
|
|
|
|
return vcpu;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_get_running_vcpu);
|
|
|
|
/**
|
|
* kvm_get_running_vcpus - get the per-CPU array of currently running vcpus.
|
|
*/
|
|
struct kvm_vcpu * __percpu *kvm_get_running_vcpus(void)
|
|
{
|
|
return &kvm_running_vcpu;
|
|
}
|
|
|
|
#ifdef CONFIG_GUEST_PERF_EVENTS
|
|
static unsigned int kvm_guest_state(void)
|
|
{
|
|
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
|
|
unsigned int state;
|
|
|
|
if (!kvm_arch_pmi_in_guest(vcpu))
|
|
return 0;
|
|
|
|
state = PERF_GUEST_ACTIVE;
|
|
if (!kvm_arch_vcpu_in_kernel(vcpu))
|
|
state |= PERF_GUEST_USER;
|
|
|
|
return state;
|
|
}
|
|
|
|
static unsigned long kvm_guest_get_ip(void)
|
|
{
|
|
struct kvm_vcpu *vcpu = kvm_get_running_vcpu();
|
|
|
|
/* Retrieving the IP must be guarded by a call to kvm_guest_state(). */
|
|
if (WARN_ON_ONCE(!kvm_arch_pmi_in_guest(vcpu)))
|
|
return 0;
|
|
|
|
return kvm_arch_vcpu_get_ip(vcpu);
|
|
}
|
|
|
|
static struct perf_guest_info_callbacks kvm_guest_cbs = {
|
|
.state = kvm_guest_state,
|
|
.get_ip = kvm_guest_get_ip,
|
|
.handle_intel_pt_intr = NULL,
|
|
};
|
|
|
|
void kvm_register_perf_callbacks(unsigned int (*pt_intr_handler)(void))
|
|
{
|
|
kvm_guest_cbs.handle_intel_pt_intr = pt_intr_handler;
|
|
perf_register_guest_info_callbacks(&kvm_guest_cbs);
|
|
}
|
|
void kvm_unregister_perf_callbacks(void)
|
|
{
|
|
perf_unregister_guest_info_callbacks(&kvm_guest_cbs);
|
|
}
|
|
#endif
|
|
|
|
int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module)
|
|
{
|
|
int r;
|
|
int cpu;
|
|
|
|
#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING
|
|
r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_ONLINE, "kvm/cpu:online",
|
|
kvm_online_cpu, kvm_offline_cpu);
|
|
if (r)
|
|
return r;
|
|
|
|
register_syscore_ops(&kvm_syscore_ops);
|
|
#endif
|
|
|
|
/* A kmem cache lets us meet the alignment requirements of fx_save. */
|
|
if (!vcpu_align)
|
|
vcpu_align = __alignof__(struct kvm_vcpu);
|
|
kvm_vcpu_cache =
|
|
kmem_cache_create_usercopy("kvm_vcpu", vcpu_size, vcpu_align,
|
|
SLAB_ACCOUNT,
|
|
offsetof(struct kvm_vcpu, arch),
|
|
offsetofend(struct kvm_vcpu, stats_id)
|
|
- offsetof(struct kvm_vcpu, arch),
|
|
NULL);
|
|
if (!kvm_vcpu_cache) {
|
|
r = -ENOMEM;
|
|
goto err_vcpu_cache;
|
|
}
|
|
|
|
for_each_possible_cpu(cpu) {
|
|
if (!alloc_cpumask_var_node(&per_cpu(cpu_kick_mask, cpu),
|
|
GFP_KERNEL, cpu_to_node(cpu))) {
|
|
r = -ENOMEM;
|
|
goto err_cpu_kick_mask;
|
|
}
|
|
}
|
|
|
|
r = kvm_irqfd_init();
|
|
if (r)
|
|
goto err_irqfd;
|
|
|
|
r = kvm_async_pf_init();
|
|
if (r)
|
|
goto err_async_pf;
|
|
|
|
kvm_chardev_ops.owner = module;
|
|
|
|
kvm_preempt_ops.sched_in = kvm_sched_in;
|
|
kvm_preempt_ops.sched_out = kvm_sched_out;
|
|
|
|
kvm_init_debug();
|
|
|
|
r = kvm_vfio_ops_init();
|
|
if (WARN_ON_ONCE(r))
|
|
goto err_vfio;
|
|
|
|
/*
|
|
* Registration _must_ be the very last thing done, as this exposes
|
|
* /dev/kvm to userspace, i.e. all infrastructure must be setup!
|
|
*/
|
|
r = misc_register(&kvm_dev);
|
|
if (r) {
|
|
pr_err("kvm: misc device register failed\n");
|
|
goto err_register;
|
|
}
|
|
|
|
return 0;
|
|
|
|
err_register:
|
|
kvm_vfio_ops_exit();
|
|
err_vfio:
|
|
kvm_async_pf_deinit();
|
|
err_async_pf:
|
|
kvm_irqfd_exit();
|
|
err_irqfd:
|
|
err_cpu_kick_mask:
|
|
for_each_possible_cpu(cpu)
|
|
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
|
|
kmem_cache_destroy(kvm_vcpu_cache);
|
|
err_vcpu_cache:
|
|
#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING
|
|
unregister_syscore_ops(&kvm_syscore_ops);
|
|
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
|
|
#endif
|
|
return r;
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_init);
|
|
|
|
void kvm_exit(void)
|
|
{
|
|
int cpu;
|
|
|
|
/*
|
|
* Note, unregistering /dev/kvm doesn't strictly need to come first,
|
|
* fops_get(), a.k.a. try_module_get(), prevents acquiring references
|
|
* to KVM while the module is being stopped.
|
|
*/
|
|
misc_deregister(&kvm_dev);
|
|
|
|
debugfs_remove_recursive(kvm_debugfs_dir);
|
|
for_each_possible_cpu(cpu)
|
|
free_cpumask_var(per_cpu(cpu_kick_mask, cpu));
|
|
kmem_cache_destroy(kvm_vcpu_cache);
|
|
kvm_vfio_ops_exit();
|
|
kvm_async_pf_deinit();
|
|
#ifdef CONFIG_KVM_GENERIC_HARDWARE_ENABLING
|
|
unregister_syscore_ops(&kvm_syscore_ops);
|
|
cpuhp_remove_state_nocalls(CPUHP_AP_KVM_ONLINE);
|
|
#endif
|
|
kvm_irqfd_exit();
|
|
}
|
|
EXPORT_SYMBOL_GPL(kvm_exit);
|
|
|
|
struct kvm_vm_worker_thread_context {
|
|
struct kvm *kvm;
|
|
struct task_struct *parent;
|
|
struct completion init_done;
|
|
kvm_vm_thread_fn_t thread_fn;
|
|
uintptr_t data;
|
|
int err;
|
|
};
|
|
|
|
static int kvm_vm_worker_thread(void *context)
|
|
{
|
|
/*
|
|
* The init_context is allocated on the stack of the parent thread, so
|
|
* we have to locally copy anything that is needed beyond initialization
|
|
*/
|
|
struct kvm_vm_worker_thread_context *init_context = context;
|
|
struct task_struct *parent;
|
|
struct kvm *kvm = init_context->kvm;
|
|
kvm_vm_thread_fn_t thread_fn = init_context->thread_fn;
|
|
uintptr_t data = init_context->data;
|
|
int err;
|
|
|
|
err = kthread_park(current);
|
|
/* kthread_park(current) is never supposed to return an error */
|
|
WARN_ON(err != 0);
|
|
if (err)
|
|
goto init_complete;
|
|
|
|
err = cgroup_attach_task_all(init_context->parent, current);
|
|
if (err) {
|
|
kvm_err("%s: cgroup_attach_task_all failed with err %d\n",
|
|
__func__, err);
|
|
goto init_complete;
|
|
}
|
|
|
|
set_user_nice(current, task_nice(init_context->parent));
|
|
|
|
init_complete:
|
|
init_context->err = err;
|
|
complete(&init_context->init_done);
|
|
init_context = NULL;
|
|
|
|
if (err)
|
|
goto out;
|
|
|
|
/* Wait to be woken up by the spawner before proceeding. */
|
|
kthread_parkme();
|
|
|
|
if (!kthread_should_stop())
|
|
err = thread_fn(kvm, data);
|
|
|
|
out:
|
|
/*
|
|
* Move kthread back to its original cgroup to prevent it lingering in
|
|
* the cgroup of the VM process, after the latter finishes its
|
|
* execution.
|
|
*
|
|
* kthread_stop() waits on the 'exited' completion condition which is
|
|
* set in exit_mm(), via mm_release(), in do_exit(). However, the
|
|
* kthread is removed from the cgroup in the cgroup_exit() which is
|
|
* called after the exit_mm(). This causes the kthread_stop() to return
|
|
* before the kthread actually quits the cgroup.
|
|
*/
|
|
rcu_read_lock();
|
|
parent = rcu_dereference(current->real_parent);
|
|
get_task_struct(parent);
|
|
rcu_read_unlock();
|
|
cgroup_attach_task_all(parent, current);
|
|
put_task_struct(parent);
|
|
|
|
return err;
|
|
}
|
|
|
|
int kvm_vm_create_worker_thread(struct kvm *kvm, kvm_vm_thread_fn_t thread_fn,
|
|
uintptr_t data, const char *name,
|
|
struct task_struct **thread_ptr)
|
|
{
|
|
struct kvm_vm_worker_thread_context init_context = {};
|
|
struct task_struct *thread;
|
|
|
|
*thread_ptr = NULL;
|
|
init_context.kvm = kvm;
|
|
init_context.parent = current;
|
|
init_context.thread_fn = thread_fn;
|
|
init_context.data = data;
|
|
init_completion(&init_context.init_done);
|
|
|
|
thread = kthread_run(kvm_vm_worker_thread, &init_context,
|
|
"%s-%d", name, task_pid_nr(current));
|
|
if (IS_ERR(thread))
|
|
return PTR_ERR(thread);
|
|
|
|
/* kthread_run is never supposed to return NULL */
|
|
WARN_ON(thread == NULL);
|
|
|
|
wait_for_completion(&init_context.init_done);
|
|
|
|
if (!init_context.err)
|
|
*thread_ptr = thread;
|
|
|
|
return init_context.err;
|
|
}
|