renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2024-12-26 22:24:09 +08:00
Code

xen p2m: transparently change the p2m mappings in the m2p override

Browse Source 
In m2p_add_override store the original mfn into page->index and then
change the p2m mapping, setting mfns as FOREIGN_FRAME.

In m2p_remove_override restore the original mapping.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
This commit is contained in:
Stefano Stabellini 2010-12-10 14:52:45 +00:00 committed by Konrad Rzeszutek Wilk
parent f0a70c882e
commit 9b705f0e98
1 changed files with 12 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
arch/x86/xen/p2m.c
View File

@ -407,8 +407,11 @@ static unsigned long mfn_hash(unsigned long mfn)
void m2p_add_override(unsigned long mfn, struct page *page)
{
unsigned long flags;
unsigned long pfn = page_to_pfn(page);
page->private = mfn;
page->index = pfn_to_mfn(pfn);
__set_phys_to_machine(pfn, FOREIGN_FRAME(mfn));
spin_lock_irqsave(&m2p_override_lock, flags);
list_add(&page->lru, &m2p_overrides[mfn_hash(mfn)]);
spin_unlock_irqrestore(&m2p_override_lock, flags);
@ -417,9 +420,18 @@ void m2p_add_override(unsigned long mfn, struct page *page)
void m2p_remove_override(struct page *page)
{
unsigned long flags;
unsigned long mfn;
unsigned long pfn;
pfn = page_to_pfn(page);
mfn = get_phys_to_machine(pfn);
if (mfn == INVALID_P2M_ENTRY || !(mfn & FOREIGN_FRAME_BIT))
return;
spin_lock_irqsave(&m2p_override_lock, flags);
list_del(&page->lru);
spin_unlock_irqrestore(&m2p_override_lock, flags);
__set_phys_to_machine(pfn, page->index);
}
struct page *m2p_find_override(unsigned long mfn)