WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

[Xen-devel] [PATCH v3 04/10] xen: map a dummy page for local apic and io

To: linux-kernel@xxxxxxxxxxxxxxx
Subject: [Xen-devel] [PATCH v3 04/10] xen: map a dummy page for local apic and ioapic in xen_set_fixmap
From: Stefano Stabellini <Stefano.Stabellini@xxxxxxxxxxxxx>
Date: Tue, 12 Oct 2010 17:42:44 +0100
Cc: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx, Jeremy.Fitzhardinge@xxxxxxxxxx, Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>, konrad.wilk@xxxxxxxxxx
Delivery-date: Tue, 12 Oct 2010 09:51:55 -0700
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <alpine.DEB.2.00.1010121043030.2422@kaball-desktop>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <alpine.DEB.2.00.1010121043030.2422@kaball-desktop>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
From: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@xxxxxxxxxx>
Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
---
 arch/x86/xen/mmu.c |   23 ++++++++++++++++++++---
 1 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/arch/x86/xen/mmu.c b/arch/x86/xen/mmu.c
index 42086ac..ffc5e24 100644
--- a/arch/x86/xen/mmu.c
+++ b/arch/x86/xen/mmu.c
@@ -1861,6 +1861,8 @@ __init pgd_t *xen_setup_kernel_pagetable(pgd_t *pgd,
 }
 #endif /* CONFIG_X86_64 */
 
+static unsigned char dummy_mapping[PAGE_SIZE] __page_aligned_bss;
+
 static void xen_set_fixmap(unsigned idx, phys_addr_t phys, pgprot_t prot)
 {
        pte_t pte;
@@ -1881,15 +1883,28 @@ static void xen_set_fixmap(unsigned idx, phys_addr_t 
phys, pgprot_t prot)
 #else
        case VSYSCALL_LAST_PAGE ... VSYSCALL_FIRST_PAGE:
 #endif
-#ifdef CONFIG_X86_LOCAL_APIC
-       case FIX_APIC_BASE:     /* maps dummy local APIC */
-#endif
        case FIX_TEXT_POKE0:
        case FIX_TEXT_POKE1:
                /* All local page mappings */
                pte = pfn_pte(phys, prot);
                break;
 
+#ifdef CONFIG_X86_LOCAL_APIC
+       case FIX_APIC_BASE:     /* maps dummy local APIC */
+               pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
+               break;
+#endif
+
+#ifdef CONFIG_X86_IO_APIC
+       case FIX_IO_APIC_BASE_0 ... FIX_IO_APIC_BASE_END:
+               /*
+                * We just don't map the IO APIC - all access is via
+                * hypercalls.  Keep the address in the pte for reference.
+                */
+               pte = pfn_pte(PFN_DOWN(__pa(dummy_mapping)), PAGE_KERNEL);
+               break;
+#endif
+
        case FIX_PARAVIRT_BOOTMAP:
                /* This is an MFN, but it isn't an IO mapping from the
                   IO domain */
@@ -2027,6 +2042,8 @@ void __init xen_init_mmu_ops(void)
        pv_mmu_ops = xen_mmu_ops;
 
        vmap_lazy_unmap = false;
+
+       memset(dummy_mapping, 0xff, PAGE_SIZE);
 }
 
 /* Protected by xen_reservation_lock. */
-- 
1.5.6.5


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

<Prev in Thread] Current Thread [Next in Thread>