[PATCH CPA] [7/28] Extract page table dumping code from i386 fault handler into dump_pagetable()

Andi Kleen
2008-01-03T15:25:56Z

Similar to x86-64. This is useful in other situations where we want
the page table dumped too.

Besides anything that makes i386 do_page_fault shorter is good.

Signed-off-by: Andi Kleen <ak@suse.de>

---
arch/x86/mm/fault_32.c | 72 ++++++++++++++++++++++++++-----------------------
1 file changed, 39 insertions(+), 33 deletions(-)

Index: linux/arch/x86/mm/fault_32.c
===================================================================
--- linux.orig/arch/x86/mm/fault_32.c
+++ linux/arch/x86/mm/fault_32.c
@@ -28,6 +28,44 @@
#include <asm/desc.h>
#include <asm/segment.h>

+void dump_pagetable(unsigned long address)
+{
+ typeof(pte_val(__pte(0))) page;
+
+ page = read_cr3();
+ page = ((__typeof__(page) *) __va(page))[address >> PGDIR_SHIFT];
+#ifdef CONFIG_X86_PAE
+ printk("*pdpt = %016Lx ", page);
+ if ((page >> PAGE_SHIFT) < max_low_pfn
+ && page & _PAGE_PRESENT) {
+ page &= PAGE_MASK;
+ page = ((__typeof__(page) *) __va(page))[(address >> PMD_SHIFT)
+ & (PTRS_PER_PMD - 1)];
+ printk(KERN_CONT "*pde = %016Lx ", page);
+ page &= ~_PAGE_NX;
+ }
+#else
+ printk("*pde = %08lx ", page);
+#endif
+
+ /*
+ * We must not directly access the pte in the highpte
+ * case if the page table is located in highmem.
+ * And let's rather not kmap-atomic the pte, just in case
+ * it's allocated already.
+ */
+ if ((page >> PAGE_SHIFT) < max_low_pfn
+ && (page & _PAGE_PRESENT)
+ && !(page & _PAGE_PSE)) {
+ page &= PAGE_MASK;
+ page = ((__typeof__(page) *) __va(page))[(address >> PAGE_SHIFT)
+ & (PTRS_PER_PTE - 1)];
+ printk("*pte = %0*Lx ", sizeof(page)*2, (u64)page);
+ }
+
+ printk("\n");
+}
+
/*
* Page fault error code bits
* bit 0 == 0 means no page found, 1 means protection fault
@@ -602,7 +640,6 @@ no_context:
bust_spinlocks(1);

if (oops_may_print()) {
- __typeof__(pte_val(__pte(0))) page;

#ifdef CONFIG_X86_PAE
if (error_code & 16) {
@@ -623,38 +660,7 @@ no_context:
printk(" at virtual address %08lx\n", address);
printk(KERN_ALERT "printing ip: %08lx ", regs->ip);

- page = read_cr3();
- page = ((__typeof__(page) *) __va(page))[address >> PGDIR_SHIFT];
-#ifdef CONFIG_X86_PAE
- printk("*pdpt = %016Lx ", page);
- if ((page >> PAGE_SHIFT) < max_low_pfn
- && page & _PAGE_PRESENT) {
- page &= PAGE_MASK;
- page = ((__typeof__(page) *) __va(page))[(address >> PMD_SHIFT)
- & (PTRS_PER_PMD - 1)];
- printk(KERN_CONT "*pde = %016Lx ", page);
- page &= ~_PAGE_NX;
- }
-#else
- printk("*pde = %08lx ", page);
-#endif
-
- /*
- * We must not directly access the pte in the highpte
- * case if the page table is located in highmem.
- * And let's rather not kmap-atomic the pte, just in case
- * it's allocated already.
- */
- if ((page >> PAGE_SHIFT) < max_low_pfn
- && (page & _PAGE_PRESENT)
- && !(page & _PAGE_PSE)) {
- page &= PAGE_MASK;
- page = ((__typeof__(page) *) __va(page))[(address >> PAGE_SHIFT)
- & (PTRS_PER_PTE - 1)];
- printk("*pte = %0*Lx ", sizeof(page)*2, (u64)page);
- }
-
- printk("\n");
+ dump_pagetable(address);
}

tsk->thread.cr2 = address;