Make the fixmap area moveable in kernel address space.

From: Gerd Hoffmann <kraxel@suse.de>
Signed-off-by: Christian Limpach <Christian.Limpach@cl.cam.ac.uk>

diff --git a/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c b/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c
index 7a32295ec6bc762811ad55b74763339562e1bf61..869d43ef896e696814bc9bfb35612b55a00dc70a 100644 (file)
--- a/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c
+++ b/linux-2.6-xen-sparse/arch/i386/mm/pgtable-xen.c
@@ -13,6 +13,7 @@
 #include <linux/slab.h>
 #include <linux/pagemap.h>
 #include <linux/spinlock.h>
+#include <linux/module.h>
 
 #include <asm/system.h>
 #include <asm/pgtable.h>
@@ -184,6 +185,10 @@ void set_pmd_pfn(unsigned long vaddr, unsigned long pfn, pgprot_t flags)
        __flush_tlb_one(vaddr);
 }
 
+static int nr_fixmaps = 0;
+unsigned long __FIXADDR_TOP = (HYPERVISOR_VIRT_START - 2 * PAGE_SIZE);
+EXPORT_SYMBOL(__FIXADDR_TOP);
+
 void __set_fixmap (enum fixed_addresses idx, maddr_t phys, pgprot_t flags)
 {
        unsigned long address = __fix_to_virt(idx);
@@ -203,6 +208,13 @@ void __set_fixmap (enum fixed_addresses idx, maddr_t phys, pgprot_t flags)
                set_pte_pfn_ma(address, phys >> PAGE_SHIFT, flags);
                break;
        }
+       nr_fixmaps++;
+}
+
+void set_fixaddr_top(unsigned long top)
+{
+       BUG_ON(nr_fixmaps > 0);
+       __FIXADDR_TOP = top - PAGE_SIZE;
 }
 
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)

diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h
index 190bc2df59cc3a93c40b9d1e985eeb8e7eb042d0..a69d5bca5a31741a326918479f62034ae4efe657 100644 (file)
--- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h
+++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/fixmap.h
@@ -20,7 +20,7 @@
  * Leave one empty page between vmalloc'ed areas and
  * the start of the fixmap.
  */
-#define __FIXADDR_TOP  (HYPERVISOR_VIRT_START - 2 * PAGE_SIZE)
+extern unsigned long __FIXADDR_TOP;
 
 #ifndef __ASSEMBLY__
 #include <linux/kernel.h>
@@ -98,8 +98,10 @@ enum fixed_addresses {
        __end_of_fixed_addresses
 };
 
-extern void __set_fixmap(
-       enum fixed_addresses idx, maddr_t phys, pgprot_t flags);
+extern void __set_fixmap(enum fixed_addresses idx,
+                                       maddr_t phys, pgprot_t flags);
+
+extern void set_fixaddr_top(unsigned long top);
 
 #define set_fixmap(idx, phys) \
                __set_fixmap(idx, phys, PAGE_KERNEL)

diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/page.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/page.h
index a923361ea2b0ad4b38295d89ee0bac5cf7190212..248743b8b6258ba6f466f3e828ed0c52c76ac168 100644 (file)
--- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/page.h
+++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/asm/page.h
@@ -294,7 +294,7 @@ extern int page_is_ram(unsigned long pagenr);
 
 #define PAGE_OFFSET            ((unsigned long)__PAGE_OFFSET)
 #define VMALLOC_RESERVE                ((unsigned long)__VMALLOC_RESERVE)
-#define MAXMEM                 (HYPERVISOR_VIRT_START-__PAGE_OFFSET-__VMALLOC_RESERVE)
+#define MAXMEM                 (__FIXADDR_TOP-__PAGE_OFFSET-__VMALLOC_RESERVE)
 #define __pa(x)                        ((unsigned long)(x)-PAGE_OFFSET)
 #define __va(x)                        ((void *)((unsigned long)(x)+PAGE_OFFSET))
 #define pfn_to_kaddr(pfn)      __va((pfn) << PAGE_SHIFT)

diff --git a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h
index fa7d6191b13d9d82546a98516f711d57b1b6a0aa..acec1ac0f811c258727b22b9e4bf86a0712241c9 100644 (file)
--- a/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h
+++ b/linux-2.6-xen-sparse/include/asm-i386/mach-xen/setup_arch_post.h
@@ -33,6 +33,8 @@ extern void nmi(void);
 
 static void __init machine_specific_arch_setup(void)
 {
+       struct xen_platform_parameters pp;
+
        HYPERVISOR_set_callbacks(
            __KERNEL_CS, (unsigned long)hypervisor_callback,
            __KERNEL_CS, (unsigned long)failsafe_callback);
@@ -40,4 +42,8 @@ static void __init machine_specific_arch_setup(void)
        HYPERVISOR_nmi_op(XENNMI_register_callback, (unsigned long)&nmi);
 
        machine_specific_modify_cpu_capabilities(&boot_cpu_data);
+
+       if (HYPERVISOR_xen_version(XENVER_platform_parameters,
+                                  &pp) == 0)
+               set_fixaddr_top(pp.virt_start - PAGE_SIZE);
 }