diff options
| author | Marcelo Tosatti <mtosatti@redhat.com> | 2007-12-20 19:18:23 -0500 |
|---|---|---|
| committer | Avi Kivity <avi@qumranet.com> | 2007-12-27 10:23:32 +0200 |
| commit | a23041c096c4c024351bc1f758807d66471b283f (patch) | |
| tree | 156c53d8c5e1f585c9818e3521608035efd98cb6 /virt/kvm | |
| parent | 9bad222c14f721daa7e0bc2863cf62caaecf14e6 (diff) | |
KVM: Add kvm_read_guest_atomic()
In preparation for a mmu spinlock, add kvm_read_guest_atomic()
and use it in fetch() and prefetch_page().
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
Diffstat (limited to 'virt/kvm')
| -rw-r--r-- | virt/kvm/kvm_main.c | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 396c61908242..c462d7e02f75 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -541,6 +541,26 @@ 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 r; + unsigned long addr; + gfn_t gfn = gpa >> PAGE_SHIFT; + int offset = offset_in_page(gpa); + + addr = gfn_to_hva(kvm, gfn); + 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; +} +EXPORT_SYMBOL(kvm_read_guest_atomic); + int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data, int offset, int len) { |