From 8e73485c7959fd25650761eab04db1e72ea14c23 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Sun, 17 May 2015 13:58:53 +0200 Subject: [PATCH] KVM: add vcpu-specific functions to read/write/translate GFNs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We need to hide SMRAM from guests not running in SMM. Therefore, all uses of kvm_read_guest* and kvm_write_guest* must be changed to use different address spaces, depending on whether the VCPU is in system management mode. We need to introduce a new family of functions for this purpose. For now, the VCPU-based functions have the same behavior as the existing per-VM ones, they just accept a different type for the first argument. Later however they will be changed to use one of many "struct kvm_memslots" stored in struct kvm, through an architecture hook. VM-based functions will unconditionally use the first memslots pointer. Whenever possible, this patch introduces slot-based functions with an __ prefix, with two wrappers for generic and vcpu-based actions. The exceptions are kvm_read_guest and kvm_write_guest, which are copied into the new functions kvm_vcpu_read_guest and kvm_vcpu_write_guest. Reviewed-by: Radim Krčmář Signed-off-by: Paolo Bonzini --- include/linux/kvm_host.h | 24 ++++++ virt/kvm/kvm_main.c | 167 ++++++++++++++++++++++++++++++++++++--- 2 files changed, 178 insertions(+), 13 deletions(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index b019fee6d941..ba1ea43998e4 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -471,6 +471,11 @@ static inline struct kvm_memslots *kvm_memslots(struct kvm *kvm) || lockdep_is_held(&kvm->slots_lock)); } +static inline struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu) +{ + return kvm_memslots(vcpu->kvm); +} + static inline struct kvm_memory_slot * id_to_memslot(struct kvm_memslots *slots, int id) { @@ -576,6 +581,25 @@ int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn); unsigned long kvm_host_page_size(struct kvm *kvm, gfn_t gfn); void mark_page_dirty(struct kvm *kvm, gfn_t gfn); +struct kvm_memslots *kvm_vcpu_memslots(struct kvm_vcpu *vcpu); +struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn); +pfn_t kvm_vcpu_gfn_to_pfn_atomic(struct kvm_vcpu *vcpu, gfn_t gfn); +pfn_t kvm_vcpu_gfn_to_pfn(struct kvm_vcpu *vcpu, gfn_t gfn); +struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn); +unsigned long kvm_vcpu_gfn_to_hva(struct kvm_vcpu *vcpu, gfn_t gfn); +unsigned long kvm_vcpu_gfn_to_hva_prot(struct kvm_vcpu *vcpu, gfn_t gfn, bool *writable); +int kvm_vcpu_read_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, void *data, int offset, + int len); +int kvm_vcpu_read_guest_atomic(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, + unsigned long len); +int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, + unsigned long len); +int kvm_vcpu_write_guest_page(struct kvm_vcpu *vcpu, gfn_t gfn, const void *data, + int offset, int len); +int kvm_vcpu_write_guest(struct kvm_vcpu *vcpu, gpa_t gpa, const void *data, + unsigned long len); +void kvm_vcpu_mark_page_dirty(struct kvm_vcpu *vcpu, gfn_t gfn); + void kvm_vcpu_block(struct kvm_vcpu *vcpu); void kvm_vcpu_kick(struct kvm_vcpu *vcpu); int kvm_vcpu_yield_to(struct kvm_vcpu *target); diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6c8e124006ad..3a121cedcc77 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1100,6 +1100,11 @@ struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_memslot); +struct kvm_memory_slot *kvm_vcpu_gfn_to_memslot(struct kvm_vcpu *vcpu, gfn_t gfn) +{ + return __gfn_to_memslot(kvm_vcpu_memslots(vcpu), gfn); +} + int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn) { struct kvm_memory_slot *memslot = gfn_to_memslot(kvm, gfn); @@ -1175,6 +1180,12 @@ unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn) } 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); + /* * If writable is set to false, the hva returned by this function is only * allowed to be read. @@ -1197,6 +1208,13 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable) 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 int get_user_page_nowait(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int write, struct page **page) { @@ -1412,12 +1430,24 @@ pfn_t gfn_to_pfn_atomic(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_pfn_atomic); +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); + 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); +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) { @@ -1458,6 +1488,16 @@ struct page *gfn_to_page(struct kvm *kvm, gfn_t gfn) } EXPORT_SYMBOL_GPL(gfn_to_page); +struct page *kvm_vcpu_gfn_to_page(struct kvm_vcpu *vcpu, gfn_t gfn) +{ + pfn_t pfn; + + pfn = kvm_vcpu_gfn_to_pfn(vcpu, gfn); + + return kvm_pfn_to_page(pfn); +} +EXPORT_SYMBOL_GPL(kvm_vcpu_gfn_to_page); + void kvm_release_page_clean(struct page *page) { WARN_ON(is_error_page(page)); @@ -1520,13 +1560,13 @@ static int next_segment(unsigned long len, int offset) return len; } -int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, - int 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_prot(kvm, gfn, NULL); + 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); @@ -1534,8 +1574,25 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, 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; @@ -1556,15 +1613,33 @@ int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len) } EXPORT_SYMBOL_GPL(kvm_read_guest); -int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, - unsigned long len) +int kvm_vcpu_read_guest(struct kvm_vcpu *vcpu, gpa_t gpa, void *data, unsigned long len) { - int r; - unsigned long addr; 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); - addr = gfn_to_hva_prot(kvm, gfn, NULL); +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(); @@ -1574,16 +1649,35 @@ int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, return -EFAULT; return 0; } -EXPORT_SYMBOL(kvm_read_guest_atomic); -int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data, - int offset, int len) +int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, + unsigned long len) +{ + gfn_t gfn = gpa >> PAGE_SHIFT; + struct kvm_memory_slot *slot = gfn_to_memslot(kvm, gfn); + int offset = offset_in_page(gpa); + + return __kvm_read_guest_atomic(slot, gfn, data, offset, len); +} +EXPORT_SYMBOL_GPL(kvm_read_guest_atomic); + +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_memory_slot *memslot, gfn_t gfn, + const void *data, int offset, int len) { int r; - struct kvm_memory_slot *memslot; unsigned long addr; - memslot = gfn_to_memslot(kvm, gfn); addr = gfn_to_hva_memslot(memslot, gfn); if (kvm_is_error_hva(addr)) return -EFAULT; @@ -1593,8 +1687,25 @@ int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data, mark_page_dirty_in_slot(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(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(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) { @@ -1616,6 +1727,27 @@ int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data, } 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); + int kvm_gfn_to_hva_cache_init(struct kvm *kvm, struct gfn_to_hva_cache *ghc, gpa_t gpa, unsigned long len) { @@ -1750,6 +1882,15 @@ void mark_page_dirty(struct kvm *kvm, gfn_t 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(memslot, gfn); +} +EXPORT_SYMBOL_GPL(kvm_vcpu_mark_page_dirty); + static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu) { if (kvm_arch_vcpu_runnable(vcpu)) { -- GitLab