diff options
| author | Gleb Natapov <gleb@redhat.com> | 2011-07-11 15:28:11 -0400 |
|---|---|---|
| committer | Avi Kivity <avi@redhat.com> | 2011-07-12 13:17:01 +0300 |
| commit | e03b644fe68b1c6401465b02724d261538dba10f (patch) | |
| tree | 9bb12d9ca9a74865618919e10922b2483a8cacdb | |
| parent | 29d03158f9d400450c17bb25ee0533b52f651d04 (diff) | |
KVM: introduce kvm_read_guest_cached
Introduce kvm_read_guest_cached() function in addition to write one we
already have.
[ by glauber: export function signature in kvm header ]
Signed-off-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Glauber Costa <glommer@redhat.com>
Acked-by: Rik van Riel <riel@redhat.com>
Tested-by: Eric Munson <emunson@mgebm.net>
Signed-off-by: Avi Kivity <avi@redhat.com>
| -rw-r--r-- | include/linux/kvm_host.h | 2 | ||||
| -rw-r--r-- | virt/kvm/kvm_main.c | 20 |
2 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 31ebb59cbd2..f7df0a3b031 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -381,6 +381,8 @@ int kvm_read_guest_page(struct kvm *kvm, gfn_t gfn, void *data, int offset, int kvm_read_guest_atomic(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len); int kvm_read_guest(struct kvm *kvm, gpa_t gpa, void *data, unsigned long len); +int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, + void *data, unsigned long len); int kvm_write_guest_page(struct kvm *kvm, gfn_t gfn, const void *data, int offset, int len); int kvm_write_guest(struct kvm *kvm, gpa_t gpa, const void *data, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 11d2783eb9d..d5ef9ebcaff 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1418,6 +1418,26 @@ int kvm_write_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, } EXPORT_SYMBOL_GPL(kvm_write_guest_cached); +int kvm_read_guest_cached(struct kvm *kvm, struct gfn_to_hva_cache *ghc, + void *data, unsigned long len) +{ + struct kvm_memslots *slots = kvm_memslots(kvm); + int r; + + if (slots->generation != ghc->generation) + kvm_gfn_to_hva_cache_init(kvm, ghc, ghc->gpa); + + if (kvm_is_error_hva(ghc->hva)) + return -EFAULT; + + r = __copy_from_user(data, (void __user *)ghc->hva, len); + if (r) + return -EFAULT; + + return 0; +} +EXPORT_SYMBOL_GPL(kvm_read_guest_cached); + int kvm_clear_guest_page(struct kvm *kvm, gfn_t gfn, int offset, int len) { return kvm_write_guest_page(kvm, gfn, (const void *) empty_zero_page, |