writeback: pay attention to wbc->nr_to_write in write_cache_pages

[safe/jmp/linux-2.6] / mm / memory.c

diff --git a/mm/memory.c b/mm/memory.c
index 1d2ea39..119b7cc 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -125,13 +125,12 @@ core_initcall(init_zero_pfn);
 
 #if defined(SPLIT_RSS_COUNTING)
 
-void __sync_task_rss_stat(struct task_struct *task, struct mm_struct *mm)
+static void __sync_task_rss_stat(struct task_struct *task, struct mm_struct *mm)
 {
        int i;
 
        for (i = 0; i < NR_MM_COUNTERS; i++) {
                if (task->rss_stat.count[i]) {
-                       BUG_ON(!mm);
                        add_mm_counter(mm, i, task->rss_stat.count[i]);
                        task->rss_stat.count[i] = 0;
                }
@@ -1228,8 +1227,17 @@ int zap_vma_ptes(struct vm_area_struct *vma, unsigned long address,
 }
 EXPORT_SYMBOL_GPL(zap_vma_ptes);
 
-/*
- * Do a quick page-table lookup for a single page.
+/**
+ * follow_page - look up a page descriptor from a user-virtual address
+ * @vma: vm_area_struct mapping @address
+ * @address: virtual address to look up
+ * @flags: flags modifying lookup behaviour
+ *
+ * @flags can have FOLL_ flags set, defined in <linux/mm.h>
+ *
+ * Returns the mapped (struct page *), %NULL if no mapping exists, or
+ * an error pointer if there is a mapping to something not represented
+ * by a page descriptor (see also vm_normal_page()).
  */
 struct page *follow_page(struct vm_area_struct *vma, unsigned long address,
                        unsigned int flags)