diff options
| author | Marcelo Tosatti | 2007-12-20 19:18:23 -0500 |
|---|---|---|
| committer | Avi Kivity | 2008-01-30 18:01:20 +0200 |
| commit | 7ec54588210df29ea637e6054489bc942c0ef371 (patch) | |
| tree | a21f672f29965a7fa35d90b3c3fe034150ae9ec7 /virt | |
| parent | 10589a4699bb978c781ce73bbae8ca942c5250c9 (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')
| -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 678e80561b74..8d0b7c16c2f7 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) { |