x86, mm: fault.c, reorder functions

Impact: cleanup

Avoid a couple more #ifdefs by moving fundamentally non-unifiable
functions into a single #ifdef 32-bit / #else / #endif block in
fault.c: vmalloc*(), dump_pagetable(), check_vm8086_mode().

No code changed:

   text	   data	    bss	    dec	    hex	filename
   4618	     32	     24	   4674	   1242	fault.o.before
   4618	     32	     24	   4674	   1242	fault.o.after

Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 239 insertions, 235 deletions

diff --git a/arch/x86/mm/fault.c b/arch/x86/mm/fault.c
index 379beaec6caa..4ce62fb80da7 100644
--- a/arch/x86/mm/fault.c
+++ b/arch/x86/mm/fault.c
@@ -191,18 +191,124 @@ force_sig_info_fault(int si_signo, int si_code, unsigned long address,
         force_sig_info(si_signo, &info, tsk);
 }
 
-#ifdef CONFIG_X86_64
-static int bad_address(void *p)
+DEFINE_SPINLOCK(pgd_lock);
+LIST_HEAD(pgd_list);
+
+#ifdef CONFIG_X86_32
+static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
 {
-        unsigned long dummy;
+        unsigned index = pgd_index(address);
+        pgd_t *pgd_k;
+        pud_t *pud, *pud_k;
+        pmd_t *pmd, *pmd_k;
 
-        return probe_kernel_address((unsigned long *)p, dummy);
+        pgd += index;
+        pgd_k = init_mm.pgd + index;
+
+        if (!pgd_present(*pgd_k))
+                return NULL;
+
+        /*
+         * set_pgd(pgd, *pgd_k); here would be useless on PAE
+         * and redundant with the set_pmd() on non-PAE. As would
+         * set_pud.
+         */
+        pud = pud_offset(pgd, address);
+        pud_k = pud_offset(pgd_k, address);
+        if (!pud_present(*pud_k))
+                return NULL;
+
+        pmd = pmd_offset(pud, address);
+        pmd_k = pmd_offset(pud_k, address);
+        if (!pmd_present(*pmd_k))
+                return NULL;
+
+        if (!pmd_present(*pmd)) {
+                set_pmd(pmd, *pmd_k);
+                arch_flush_lazy_mmu_mode();
+        } else {
+                BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
+        }
+
+        return pmd_k;
+}
+
+void vmalloc_sync_all(void)
+{
+        unsigned long address;
+
+        if (SHARED_KERNEL_PMD)
+                return;
+
+        for (address = VMALLOC_START & PMD_MASK;
+             address >= TASK_SIZE && address < FIXADDR_TOP;
+             address += PMD_SIZE) {
+
+                unsigned long flags;
+                struct page *page;
+
+                spin_lock_irqsave(&pgd_lock, flags);
+                list_for_each_entry(page, &pgd_list, lru) {
+                        if (!vmalloc_sync_one(page_address(page), address))
+                                break;
+                }
+                spin_unlock_irqrestore(&pgd_lock, flags);
+        }
+}
+
+/*
+ * 32-bit:
+ *
+ *   Handle a fault on the vmalloc or module mapping area
+ */
+static noinline int vmalloc_fault(unsigned long address)
+{
+        unsigned long pgd_paddr;
+        pmd_t *pmd_k;
+        pte_t *pte_k;
+
+        /* Make sure we are in vmalloc area: */
+        if (!(address >= VMALLOC_START && address < VMALLOC_END))
+                return -1;
+
+        /*
+         * Synchronize this task's top level page-table
+         * with the 'reference' page table.
+         *
+         * Do _not_ use "current" here. We might be inside
+         * an interrupt in the middle of a task switch..
+         */
+        pgd_paddr = read_cr3();
+        pmd_k = vmalloc_sync_one(__va(pgd_paddr), address);
+        if (!pmd_k)
+                return -1;
+
+        pte_k = pte_offset_kernel(pmd_k, address);
+        if (!pte_present(*pte_k))
+                return -1;
+
+        return 0;
+}
+
+/*
+ * Did it hit the DOS screen memory VA from vm86 mode?
+ */
+static inline void
+check_v8086_mode(struct pt_regs *regs, unsigned long address,
+                 struct task_struct *tsk)
+{
+        unsigned long bit;
+
+        if (!v8086_mode(regs))
+                return;
+
+        bit = (address - 0xA0000) >> PAGE_SHIFT;
+        if (bit < 32)
+                tsk->thread.screen_bitmap |= 1 << bit;
 }
-#endif
 
 static void dump_pagetable(unsigned long address)
 {
-#ifdef CONFIG_X86_32
         __typeof__(pte_val(__pte(0))) page;
 
         page = read_cr3();
@@ -239,7 +345,132 @@ static void dump_pagetable(unsigned long address)
         }
 
         printk("\n");
-#else /* CONFIG_X86_64 */
+}
+
+#else /* CONFIG_X86_64: */
+
+void vmalloc_sync_all(void)
+{
+        unsigned long address;
+
+        for (address = VMALLOC_START & PGDIR_MASK; address <= VMALLOC_END;
+             address += PGDIR_SIZE) {
+
+                const pgd_t *pgd_ref = pgd_offset_k(address);
+                unsigned long flags;
+                struct page *page;
+
+                if (pgd_none(*pgd_ref))
+                        continue;
+
+                spin_lock_irqsave(&pgd_lock, flags);
+                list_for_each_entry(page, &pgd_list, lru) {
+                        pgd_t *pgd;
+                        pgd = (pgd_t *)page_address(page) + pgd_index(address);
+                        if (pgd_none(*pgd))
+                                set_pgd(pgd, *pgd_ref);
+                        else
+                                BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+                }
+                spin_unlock_irqrestore(&pgd_lock, flags);
+        }
+}
+
+/*
+ * 64-bit:
+ *
+ *   Handle a fault on the vmalloc area
+ *
+ * This assumes no large pages in there.
+ */
+static noinline int vmalloc_fault(unsigned long address)
+{
+        pgd_t *pgd, *pgd_ref;
+        pud_t *pud, *pud_ref;
+        pmd_t *pmd, *pmd_ref;
+        pte_t *pte, *pte_ref;
+
+        /* Make sure we are in vmalloc area: */
+        if (!(address >= VMALLOC_START && address < VMALLOC_END))
+                return -1;
+
+        /*
+         * Copy kernel mappings over when needed. This can also
+         * happen within a race in page table update. In the later
+         * case just flush:
+         */
+        pgd = pgd_offset(current->active_mm, address);
+        pgd_ref = pgd_offset_k(address);
+        if (pgd_none(*pgd_ref))
+                return -1;
+
+        if (pgd_none(*pgd))
+                set_pgd(pgd, *pgd_ref);
+        else
+                BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+
+        /*
+         * Below here mismatches are bugs because these lower tables
+         * are shared:
+         */
+
+        pud = pud_offset(pgd, address);
+        pud_ref = pud_offset(pgd_ref, address);
+        if (pud_none(*pud_ref))
+                return -1;
+
+        if (pud_none(*pud) || pud_page_vaddr(*pud) != pud_page_vaddr(*pud_ref))
+                BUG();
+
+        pmd = pmd_offset(pud, address);
+        pmd_ref = pmd_offset(pud_ref, address);
+        if (pmd_none(*pmd_ref))
+                return -1;
+
+        if (pmd_none(*pmd) || pmd_page(*pmd) != pmd_page(*pmd_ref))
+                BUG();
+
+        pte_ref = pte_offset_kernel(pmd_ref, address);
+        if (!pte_present(*pte_ref))
+                return -1;
+
+        pte = pte_offset_kernel(pmd, address);
+
+        /*
+         * Don't use pte_page here, because the mappings can point
+         * outside mem_map, and the NUMA hash lookup cannot handle
+         * that:
+         */
+        if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref))
+                BUG();
+
+        return 0;
+}
+
+static const char errata93_warning[] =
+KERN_ERR "******* Your BIOS seems to not contain a fix for K8 errata #93\n"
+KERN_ERR "******* Working around it, but it may cause SEGVs or burn power.\n"
+KERN_ERR "******* Please consider a BIOS update.\n"
+KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n";
+
+/*
+ * No vm86 mode in 64-bit mode:
+ */
+static inline void
+check_v8086_mode(struct pt_regs *regs, unsigned long address,
+                 struct task_struct *tsk)
+{
+}
+
+static int bad_address(void *p)
+{
+        unsigned long dummy;
+
+        return probe_kernel_address((unsigned long *)p, dummy);
+}
+
+static void dump_pagetable(unsigned long address)
+{
         pgd_t *pgd;
         pud_t *pud;
         pmd_t *pmd;
@@ -284,83 +515,9 @@ out:
         return;
 bad:
         printk("BAD\n");
-#endif
-}
-
-#ifdef CONFIG_X86_32
-static inline pmd_t *vmalloc_sync_one(pgd_t *pgd, unsigned long address)
-{
-        unsigned index = pgd_index(address);
-        pgd_t *pgd_k;
-        pud_t *pud, *pud_k;
-        pmd_t *pmd, *pmd_k;
-
-        pgd += index;
-        pgd_k = init_mm.pgd + index;
-
-        if (!pgd_present(*pgd_k))
-                return NULL;
-
-        /*
-         * set_pgd(pgd, *pgd_k); here would be useless on PAE
-         * and redundant with the set_pmd() on non-PAE. As would
-         * set_pud.
-         */
-        pud = pud_offset(pgd, address);
-        pud_k = pud_offset(pgd_k, address);
-        if (!pud_present(*pud_k))
-                return NULL;
-
-        pmd = pmd_offset(pud, address);
-        pmd_k = pmd_offset(pud_k, address);
-        if (!pmd_present(*pmd_k))
-                return NULL;
-
-        if (!pmd_present(*pmd)) {
-                set_pmd(pmd, *pmd_k);
-                arch_flush_lazy_mmu_mode();
-        } else {
-                BUG_ON(pmd_page(*pmd) != pmd_page(*pmd_k));
-        }
-
-        return pmd_k;
-}
-
-/*
- * Did it hit the DOS screen memory VA from vm86 mode?
- */
-static inline void
-check_v8086_mode(struct pt_regs *regs, unsigned long address,
-                 struct task_struct *tsk)
-{
-        unsigned long bit;
-
-        if (!v8086_mode(regs))
-                return;
-
-        bit = (address - 0xA0000) >> PAGE_SHIFT;
-        if (bit < 32)
-                tsk->thread.screen_bitmap |= 1 << bit;
-}
-
-#else /* CONFIG_X86_64: */
-
-static const char errata93_warning[] =
-KERN_ERR "******* Your BIOS seems to not contain a fix for K8 errata #93\n"
-KERN_ERR "******* Working around it, but it may cause SEGVs or burn power.\n"
-KERN_ERR "******* Please consider a BIOS update.\n"
-KERN_ERR "******* Disabling USB legacy in the BIOS may also help.\n";
-
-/*
- * No vm86 mode in 64-bit mode:
- */
-static inline void
-check_v8086_mode(struct pt_regs *regs, unsigned long address,
-                 struct task_struct *tsk)
-{
 }
 
-#endif
+#endif /* CONFIG_X86_64 */
 
 /*
  * Workaround for K8 erratum #93 & buggy BIOS.
@@ -795,109 +952,6 @@ spurious_fault(unsigned long error_code, unsigned long address)
         return ret;
 }
 
-/*
- * 32-bit:
- *
- *   Handle a fault on the vmalloc or module mapping area
- *
- * 64-bit:
- *
- *   Handle a fault on the vmalloc area
- *
- * This assumes no large pages in there.
- */
-static noinline int vmalloc_fault(unsigned long address)
-{
-#ifdef CONFIG_X86_32
-        unsigned long pgd_paddr;
-        pmd_t *pmd_k;
-        pte_t *pte_k;
-
-        /* Make sure we are in vmalloc area: */
-        if (!(address >= VMALLOC_START && address < VMALLOC_END))
-                return -1;
-
-        /*
-         * Synchronize this task's top level page-table
-         * with the 'reference' page table.
-         *
-         * Do _not_ use "current" here. We might be inside
-         * an interrupt in the middle of a task switch..
-         */
-        pgd_paddr = read_cr3();
-        pmd_k = vmalloc_sync_one(__va(pgd_paddr), address);
-        if (!pmd_k)
-                return -1;
-
-        pte_k = pte_offset_kernel(pmd_k, address);
-        if (!pte_present(*pte_k))
-                return -1;
-
-        return 0;
-#else
-        pgd_t *pgd, *pgd_ref;
-        pud_t *pud, *pud_ref;
-        pmd_t *pmd, *pmd_ref;
-        pte_t *pte, *pte_ref;
-
-        /* Make sure we are in vmalloc area: */
-        if (!(address >= VMALLOC_START && address < VMALLOC_END))
-                return -1;
-
-        /*
-         * Copy kernel mappings over when needed. This can also
-         * happen within a race in page table update. In the later
-         * case just flush:
-         */
-        pgd = pgd_offset(current->active_mm, address);
-        pgd_ref = pgd_offset_k(address);
-        if (pgd_none(*pgd_ref))
-                return -1;
-
-        if (pgd_none(*pgd))
-                set_pgd(pgd, *pgd_ref);
-        else
-                BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
-
-        /*
-         * Below here mismatches are bugs because these lower tables
-         * are shared:
-         */
-
-        pud = pud_offset(pgd, address);
-        pud_ref = pud_offset(pgd_ref, address);
-        if (pud_none(*pud_ref))
-                return -1;
-
-        if (pud_none(*pud) || pud_page_vaddr(*pud) != pud_page_vaddr(*pud_ref))
-                BUG();
-
-        pmd = pmd_offset(pud, address);
-        pmd_ref = pmd_offset(pud_ref, address);
-        if (pmd_none(*pmd_ref))
-                return -1;
-
-        if (pmd_none(*pmd) || pmd_page(*pmd) != pmd_page(*pmd_ref))
-                BUG();
-
-        pte_ref = pte_offset_kernel(pmd_ref, address);
-        if (!pte_present(*pte_ref))
-                return -1;
-
-        pte = pte_offset_kernel(pmd, address);
-
-        /*
-         * Don't use pte_page here, because the mappings can point
-         * outside mem_map, and the NUMA hash lookup cannot handle
-         * that:
-         */
-        if (!pte_present(*pte) || pte_pfn(*pte) != pte_pfn(*pte_ref))
-                BUG();
-
-        return 0;
-#endif
-}
-
 int show_unhandled_signals = 1;
 
 static inline int
@@ -1115,53 +1169,3 @@ good_area:
 
         up_read(&mm->mmap_sem);
 }
-
-DEFINE_SPINLOCK(pgd_lock);
-LIST_HEAD(pgd_list);
-
-void vmalloc_sync_all(void)
-{
-        unsigned long address;
-
-#ifdef CONFIG_X86_32
-        if (SHARED_KERNEL_PMD)
-                return;
-
-        for (address = VMALLOC_START & PMD_MASK;
-             address >= TASK_SIZE && address < FIXADDR_TOP;
-             address += PMD_SIZE) {
-
-                unsigned long flags;
-                struct page *page;
-
-                spin_lock_irqsave(&pgd_lock, flags);
-                list_for_each_entry(page, &pgd_list, lru) {
-                        if (!vmalloc_sync_one(page_address(page), address))
-                                break;
-                }
-                spin_unlock_irqrestore(&pgd_lock, flags);
-        }
-#else /* CONFIG_X86_64 */
-        for (address = VMALLOC_START & PGDIR_MASK; address <= VMALLOC_END;
-             address += PGDIR_SIZE) {
-
-                const pgd_t *pgd_ref = pgd_offset_k(address);
-                unsigned long flags;
-                struct page *page;
-
-                if (pgd_none(*pgd_ref))
-                        continue;
-
-                spin_lock_irqsave(&pgd_lock, flags);
-                list_for_each_entry(page, &pgd_list, lru) {
-                        pgd_t *pgd;
-                        pgd = (pgd_t *)page_address(page) + pgd_index(address);
-                        if (pgd_none(*pgd))
-                                set_pgd(pgd, *pgd_ref);
-                        else
-                                BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
-                }
-                spin_unlock_irqrestore(&pgd_lock, flags);
-        }
-#endif
-}