lkml.org 
[lkml]   [2007]   [Dec]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 45/55] KVM: introduce gfn_to_hva()
Date
From: Izik Eidus <izike@qumranet.com>

Convert a guest frame number to the corresponding host virtual address.

Signed-off-by: Izik Eidus <izike@qumranet.com>
Signed-off-by: Avi Kivity <avi@qumranet.com>
---
drivers/kvm/kvm_main.c | 25 +++++++++++++++++--------
1 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index e3c7f3b..d318c28 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -559,28 +559,37 @@ int kvm_is_visible_gfn(struct kvm *kvm, gfn_t gfn)
}
EXPORT_SYMBOL_GPL(kvm_is_visible_gfn);

+static unsigned long gfn_to_hva(struct kvm *kvm, gfn_t gfn)
+{
+ struct kvm_memory_slot *slot;
+
+ gfn = unalias_gfn(kvm, gfn);
+ slot = __gfn_to_memslot(kvm, gfn);
+ if (!slot)
+ return bad_hva();
+ return (slot->userspace_addr + (gfn - slot->base_gfn) * PAGE_SIZE);
+}
+
/*
* Requires current->mm->mmap_sem to be held
*/
static struct page *__gfn_to_page(struct kvm *kvm, gfn_t gfn)
{
- struct kvm_memory_slot *slot;
struct page *page[1];
+ unsigned long addr;
int npages;

might_sleep();

- gfn = unalias_gfn(kvm, gfn);
- slot = __gfn_to_memslot(kvm, gfn);
- if (!slot) {
+ addr = gfn_to_hva(kvm, gfn);
+ if (kvm_is_error_hva(addr)) {
get_page(bad_page);
return bad_page;
}

- npages = get_user_pages(current, current->mm,
- slot->userspace_addr
- + (gfn - slot->base_gfn) * PAGE_SIZE, 1,
- 1, 1, page, NULL);
+ npages = get_user_pages(current, current->mm, addr, 1, 1, 1, page,
+ NULL);
+
if (npages != 1) {
get_page(bad_page);
return bad_page;
--
1.5.3.7


\
 
 \ /
  Last update: 2007-12-26 12:25    [W:0.125 / U:0.500 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site