Merge branch 'drm-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied...

[sfrench/cifs-2.6.git] / arch / x86_64 / mm / fault.c

diff --git a/arch/x86_64/mm/fault.c b/arch/x86_64/mm/fault.c
index 2e7c3c8ffe035d0981b29fd052da25cb86e21d41..316c53de47bd8574cd530b8fd76e7405bc1f6df0 100644 (file)
--- a/arch/x86_64/mm/fault.c
+++ b/arch/x86_64/mm/fault.c
@@ -264,6 +264,8 @@ static int vmalloc_fault(unsigned long address)
                return -1;
        if (pgd_none(*pgd))
                set_pgd(pgd, *pgd_ref);
+       else
+               BUG_ON(pgd_page(*pgd) != pgd_page(*pgd_ref));
 
        /* Below here mismatches are bugs because these lower tables
           are shared */
@@ -312,21 +314,13 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        unsigned long flags;
        siginfo_t info;
 
+       tsk = current;
+       mm = tsk->mm;
+       prefetchw(&mm->mmap_sem);
+
        /* get the address */
        __asm__("movq %%cr2,%0":"=r" (address));
-       if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
-                                       SIGSEGV) == NOTIFY_STOP)
-               return;
-
-       if (likely(regs->eflags & X86_EFLAGS_IF))
-               local_irq_enable();
 
-       if (unlikely(page_fault_trace))
-               printk("pagefault rip:%lx rsp:%lx cs:%lu ss:%lu address %lx error %lx\n",
-                      regs->rip,regs->rsp,regs->cs,regs->ss,address,error_code); 
-
-       tsk = current;
-       mm = tsk->mm;
        info.si_code = SEGV_MAPERR;
 
 
@@ -351,10 +345,12 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
                 */
                if (!(error_code & (PF_RSVD|PF_USER|PF_PROT)) &&
                      ((address >= VMALLOC_START && address < VMALLOC_END))) {
-                       if (vmalloc_fault(address) < 0)
-                               goto bad_area_nosemaphore;
-                       return;
+                       if (vmalloc_fault(address) >= 0)
+                               return;
                }
+               if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+                                               SIGSEGV) == NOTIFY_STOP)
+                       return;
                /*
                 * Don't take the mm semaphore here. If we fixup a prefetch
                 * fault we could otherwise deadlock.
@@ -362,6 +358,17 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
                goto bad_area_nosemaphore;
        }
 
+       if (notify_die(DIE_PAGE_FAULT, "page fault", regs, error_code, 14,
+                                       SIGSEGV) == NOTIFY_STOP)
+               return;
+
+       if (likely(regs->eflags & X86_EFLAGS_IF))
+               local_irq_enable();
+
+       if (unlikely(page_fault_trace))
+               printk("pagefault rip:%lx rsp:%lx cs:%lu ss:%lu address %lx error %lx\n",
+                      regs->rip,regs->rsp,regs->cs,regs->ss,address,error_code); 
+
        if (unlikely(error_code & PF_RSVD))
                pgtable_bad(address, regs, error_code);
 
@@ -571,6 +578,48 @@ do_sigbus:
        return;
 }
 
+DEFINE_SPINLOCK(pgd_lock);
+struct page *pgd_list;
+
+void vmalloc_sync_all(void)
+{
+       /* Note that races in the updates of insync and start aren't 
+          problematic:
+          insync can only get set bits added, and updates to start are only
+          improving performance (without affecting correctness if undone). */
+       static DECLARE_BITMAP(insync, PTRS_PER_PGD);
+       static unsigned long start = VMALLOC_START & PGDIR_MASK;
+       unsigned long address;
+
+       for (address = start; address <= VMALLOC_END; address += PGDIR_SIZE) {
+               if (!test_bit(pgd_index(address), insync)) {
+                       const pgd_t *pgd_ref = pgd_offset_k(address);
+                       struct page *page;
+
+                       if (pgd_none(*pgd_ref))
+                               continue;
+                       spin_lock(&pgd_lock);
+                       for (page = pgd_list; page;
+                            page = (struct page *)page->index) {
+                               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(*pgd) != pgd_page(*pgd_ref));
+                       }
+                       spin_unlock(&pgd_lock);
+                       set_bit(pgd_index(address), insync);
+               }
+               if (address == start)
+                       start = address + PGDIR_SIZE;
+       }
+       /* Check that there is no need to do the same for the modules area. */
+       BUILD_BUG_ON(!(MODULES_VADDR > __START_KERNEL));
+       BUILD_BUG_ON(!(((MODULES_END - 1) & PGDIR_MASK) == 
+                               (__START_KERNEL & PGDIR_MASK)));
+}
+
 static int __init enable_pagefaulttrace(char *str)
 {
        page_fault_trace = 1;