kexec/i386: allocate page table pages dynamically

[pandora-kernel.git] / arch / x86 / kernel / machine_kexec_32.c

diff --git a/arch/x86/kernel/machine_kexec_32.c b/arch/x86/kernel/machine_kexec_32.c
index 7a38574..1100312 100644 (file)
--- a/arch/x86/kernel/machine_kexec_32.c
+++ b/arch/x86/kernel/machine_kexec_32.c
@@ -13,6 +13,7 @@
 #include <linux/numa.h>
 #include <linux/ftrace.h>
 #include <linux/suspend.h>
+#include <linux/gfp.h>
 
 #include <asm/pgtable.h>
 #include <asm/pgalloc.h>
@@ -25,15 +26,6 @@
 #include <asm/system.h>
 #include <asm/cacheflush.h>
 
-#define PAGE_ALIGNED __attribute__ ((__aligned__(PAGE_SIZE)))
-static u32 kexec_pgd[1024] PAGE_ALIGNED;
-#ifdef CONFIG_X86_PAE
-static u32 kexec_pmd0[1024] PAGE_ALIGNED;
-static u32 kexec_pmd1[1024] PAGE_ALIGNED;
-#endif
-static u32 kexec_pte0[1024] PAGE_ALIGNED;
-static u32 kexec_pte1[1024] PAGE_ALIGNED;
-
 static void set_idt(void *newidt, __u16 limit)
 {
        struct desc_ptr curidt;
@@ -76,6 +68,37 @@ static void load_segments(void)
 #undef __STR
 }
 
+static void machine_kexec_free_page_tables(struct kimage *image)
+{
+       free_page((unsigned long)image->arch.pgd);
+#ifdef CONFIG_X86_PAE
+       free_page((unsigned long)image->arch.pmd0);
+       free_page((unsigned long)image->arch.pmd1);
+#endif
+       free_page((unsigned long)image->arch.pte0);
+       free_page((unsigned long)image->arch.pte1);
+}
+
+static int machine_kexec_alloc_page_tables(struct kimage *image)
+{
+       image->arch.pgd = (pgd_t *)get_zeroed_page(GFP_KERNEL);
+#ifdef CONFIG_X86_PAE
+       image->arch.pmd0 = (pmd_t *)get_zeroed_page(GFP_KERNEL);
+       image->arch.pmd1 = (pmd_t *)get_zeroed_page(GFP_KERNEL);
+#endif
+       image->arch.pte0 = (pte_t *)get_zeroed_page(GFP_KERNEL);
+       image->arch.pte1 = (pte_t *)get_zeroed_page(GFP_KERNEL);
+       if (!image->arch.pgd ||
+#ifdef CONFIG_X86_PAE
+           !image->arch.pmd0 || !image->arch.pmd1 ||
+#endif
+           !image->arch.pte0 || !image->arch.pte1) {
+               machine_kexec_free_page_tables(image);
+               return -ENOMEM;
+       }
+       return 0;
+}
+
 /*
  * A architecture hook called to validate the
  * proposed image and prepare the control pages
@@ -87,13 +110,14 @@ static void load_segments(void)
  * reboot code buffer to allow us to avoid allocations
  * later.
  *
- * Make control page executable.
+ * - Make control page executable.
+ * - Allocate page tables
  */
 int machine_kexec_prepare(struct kimage *image)
 {
        if (nx_enabled)
                set_pages_x(image->control_code_page, 1);
-       return 0;
+       return machine_kexec_alloc_page_tables(image);
 }
 
 /*
@@ -104,6 +128,7 @@ void machine_kexec_cleanup(struct kimage *image)
 {
        if (nx_enabled)
                set_pages_nx(image->control_code_page, 1);
+       machine_kexec_free_page_tables(image);
 }
 
 /*
@@ -150,18 +175,18 @@ void machine_kexec(struct kimage *image)
        relocate_kernel_ptr = control_page;
        page_list[PA_CONTROL_PAGE] = __pa(control_page);
        page_list[VA_CONTROL_PAGE] = (unsigned long)control_page;
-       page_list[PA_PGD] = __pa(kexec_pgd);
-       page_list[VA_PGD] = (unsigned long)kexec_pgd;
+       page_list[PA_PGD] = __pa(image->arch.pgd);
+       page_list[VA_PGD] = (unsigned long)image->arch.pgd;
 #ifdef CONFIG_X86_PAE
-       page_list[PA_PMD_0] = __pa(kexec_pmd0);
-       page_list[VA_PMD_0] = (unsigned long)kexec_pmd0;
-       page_list[PA_PMD_1] = __pa(kexec_pmd1);
-       page_list[VA_PMD_1] = (unsigned long)kexec_pmd1;
+       page_list[PA_PMD_0] = __pa(image->arch.pmd0);
+       page_list[VA_PMD_0] = (unsigned long)image->arch.pmd0;
+       page_list[PA_PMD_1] = __pa(image->arch.pmd1);
+       page_list[VA_PMD_1] = (unsigned long)image->arch.pmd1;
 #endif
-       page_list[PA_PTE_0] = __pa(kexec_pte0);
-       page_list[VA_PTE_0] = (unsigned long)kexec_pte0;
-       page_list[PA_PTE_1] = __pa(kexec_pte1);
-       page_list[VA_PTE_1] = (unsigned long)kexec_pte1;
+       page_list[PA_PTE_0] = __pa(image->arch.pte0);
+       page_list[VA_PTE_0] = (unsigned long)image->arch.pte0;
+       page_list[PA_PTE_1] = __pa(image->arch.pte1);
+       page_list[VA_PTE_1] = (unsigned long)image->arch.pte1;
 
        if (image->type == KEXEC_TYPE_DEFAULT)
                page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page)