vfs: Add no_nrwrite_index_update writeback control flag

[safe/jmp/linux-2.6] / include / linux / writeback.h

diff --git a/include/linux/writeback.h b/include/linux/writeback.h
index f462439..e585657 100644 (file)
--- a/include/linux/writeback.h
+++ b/include/linux/writeback.h
@@ -63,6 +63,15 @@ struct writeback_control {
        unsigned for_writepages:1;      /* This is a writepages() call */
        unsigned range_cyclic:1;        /* range_start is cyclic */
        unsigned more_io:1;             /* more io to be dispatched */
+       /*
+        * write_cache_pages() won't update wbc->nr_to_write and
+        * mapping->writeback_index if no_nrwrite_index_update
+        * is set.  write_cache_pages() may write more than we
+        * requested and we want to make sure nr_to_write and
+        * writeback_index are updated in a consistent manner
+        * so we use a single control to update them
+        */
+       unsigned no_nrwrite_index_update:1;
 };
 
 /*
@@ -105,6 +114,8 @@ extern int vm_highmem_is_dirtyable;
 extern int block_dump;
 extern int laptop_mode;
 
+extern unsigned long determine_dirtyable_memory(void);
+
 extern int dirty_ratio_handler(struct ctl_table *table, int write,
                struct file *filp, void __user *buffer, size_t *lenp,
                loff_t *ppos);