diff options
| author |   Stefano Stabellini <stefano.stabellini@eu.citrix.com> | 2010-12-10 14:52:45 +0000 |
|---|---|---|
| committer |   Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> | 2011-01-11 14:31:53 -0500 |
| commit | 9b705f0e98c489b18ba22a6eab9d694b546c8552 (patch) | |
| tree | e8e017032a3e433c7c637c9121eb7fbe5ee8567e | |
| parent | xen/gntdev: Fix circular locking dependency (diff) | |
| download | linux-dev-9b705f0e98c489b18ba22a6eab9d694b546c8552.tar.xz linux-dev-9b705f0e98c489b18ba22a6eab9d694b546c8552.zip | |
xen p2m: transparently change the p2m mappings in the m2p override
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>
| -rw-r--r-- | arch/x86/xen/p2m.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/xen/p2m.c b/arch/x86/xen/p2m.c index 8db19d50c467..b3b19d43b951 100644 --- a/arch/x86/xen/p2m.c +++ b/arch/x86/xen/p2m.c @@ -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) |