fedora core 6 1.2949 + vserver 2.2.0

[linux-2.6.git] / mm / rmap.c

diff --git a/mm/rmap.c b/mm/rmap.c
index bca42f9..ba4fe10 100644 (file)
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -21,27 +21,21 @@
  * Lock ordering in mm:
  *
  * inode->i_mutex      (while writing or truncating, not reading or faulting)
- *   inode->i_alloc_sem
- *
- * When a page fault occurs in writing from user to file, down_read
- * of mmap_sem nests within i_mutex; in sys_msync, i_mutex nests within
- * down_read of mmap_sem; i_mutex and down_write of mmap_sem are never
- * taken together; in truncation, i_mutex is taken outermost.
- *
- * mm->mmap_sem
- *   page->flags PG_locked (lock_page)
- *     mapping->i_mmap_lock
- *       anon_vma->lock
- *         mm->page_table_lock or pte_lock
- *           zone->lru_lock (in mark_page_accessed, isolate_lru_page)
- *           swap_lock (in swap_duplicate, swap_info_get)
- *             mmlist_lock (in mmput, drain_mmlist and others)
- *             mapping->private_lock (in __set_page_dirty_buffers)
- *             inode_lock (in set_page_dirty's __mark_inode_dirty)
- *               sb_lock (within inode_lock in fs/fs-writeback.c)
- *               mapping->tree_lock (widely used, in set_page_dirty,
- *                         in arch-dependent flush_dcache_mmap_lock,
- *                         within inode_lock in __sync_single_inode)
+ *   inode->i_alloc_sem (vmtruncate_range)
+ *   mm->mmap_sem
+ *     page->flags PG_locked (lock_page)
+ *       mapping->i_mmap_lock
+ *         anon_vma->lock
+ *           mm->page_table_lock or pte_lock
+ *             zone->lru_lock (in mark_page_accessed, isolate_lru_page)
+ *             swap_lock (in swap_duplicate, swap_info_get)
+ *               mmlist_lock (in mmput, drain_mmlist and others)
+ *               mapping->private_lock (in __set_page_dirty_buffers)
+ *               inode_lock (in set_page_dirty's __mark_inode_dirty)
+ *                 sb_lock (within inode_lock in fs/fs-writeback.c)
+ *                 mapping->tree_lock (widely used, in set_page_dirty,
+ *                           in arch-dependent flush_dcache_mmap_lock,
+ *                           within inode_lock in __sync_single_inode)
  */
 
 #include <linux/mm.h>
@@ -440,7 +434,7 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma)
 {
        struct mm_struct *mm = vma->vm_mm;
        unsigned long address;
-       pte_t *pte, entry;
+       pte_t *pte;
        spinlock_t *ptl;
        int ret = 0;
 
@@ -452,17 +446,18 @@ static int page_mkclean_one(struct page *page, struct vm_area_struct *vma)
        if (!pte)
                goto out;
 
-       if (!pte_dirty(*pte) && !pte_write(*pte))
-               goto unlock;
+       if (pte_dirty(*pte) || pte_write(*pte)) {
+               pte_t entry;
 
-       entry = ptep_get_and_clear(mm, address, pte);
-       entry = pte_mkclean(entry);
-       entry = pte_wrprotect(entry);
-       ptep_establish(vma, address, pte, entry);
-       lazy_mmu_prot_update(entry);
-       ret = 1;
+               flush_cache_page(vma, address, pte_pfn(*pte));
+               entry = ptep_clear_flush(vma, address, pte);
+               entry = pte_wrprotect(entry);
+               entry = pte_mkclean(entry);
+               set_pte_at(mm, address, pte, entry);
+               lazy_mmu_prot_update(entry);
+               ret = 1;
+       }
 
-unlock:
        pte_unmap_unlock(pte, ptl);
 out:
        return ret;
@@ -490,13 +485,15 @@ int page_mkclean(struct page *page)
 {
        int ret = 0;
 
-       WARN_ON_ONCE(!PageLocked(page));
+       BUG_ON(!PageLocked(page));
 
        if (page_mapped(page)) {
                struct address_space *mapping = page_mapping(page);
                if (mapping)
                        ret = page_mkclean_file(mapping, page);
        }
+       if (page_test_and_clear_dirty(page))
+               ret = 1;
 
        return ret;
 }
@@ -580,13 +577,18 @@ void page_remove_rmap(struct page *page, struct vm_area_struct *vma)
        if (atomic_add_negative(-1, &page->_mapcount)) {
                if (unlikely(page_mapcount(page) < 0)) {
                        printk (KERN_EMERG "Eeek! page_mapcount(page) went negative! (%d)\n", page_mapcount(page));
+                       printk (KERN_EMERG "  page pfn = %lx\n", page_to_pfn(page));
                        printk (KERN_EMERG "  page->flags = %lx\n", page->flags);
                        printk (KERN_EMERG "  page->count = %x\n", page_count(page));
                        printk (KERN_EMERG "  page->mapping = %p\n", page->mapping);
+                       print_symbol (KERN_EMERG "  vma->vm_ops = %s\n", (unsigned long)vma->vm_ops);
                        if (vma->vm_ops)
                                print_symbol (KERN_EMERG "  vma->vm_ops->nopage = %s\n", (unsigned long)vma->vm_ops->nopage);
+                       if (vma->vm_file && vma->vm_file->f_op)
+                               print_symbol (KERN_EMERG "  vma->vm_file->f_op->mmap = %s\n", (unsigned long)vma->vm_file->f_op->mmap);
                        BUG();
                }
+
                /*
                 * It would be tidy to reset the PageAnon mapping here,
                 * but that might overwrite a racing page_add_anon_rmap