Messages in this thread Patch in this message |  | | | From | stefano.stabellini@eu ... | | Subject | [PATCH 09/12] xen p2m: transparently change the p2m mappings in the m2p override | | Date | Mon, 10 Jan 2011 10:36:38 +0000 |
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From: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
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> --- 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 8db19d5..b3b19d4 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) -- 1.5.6.5
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