1 files changed, 33 insertions, 11 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 4b37f7cea4dd..1d1088f48bc2 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -42,9 +42,9 @@ struct wb_writeback_args {
         long nr_pages;
         struct super_block *sb;
         enum writeback_sync_modes sync_mode;
-        int for_kupdate:1;
-        int range_cyclic:1;
-        int for_background:1;
+        unsigned int for_kupdate:1;
+        unsigned int range_cyclic:1;
+        unsigned int for_background:1;
 };
 
 /*
@@ -398,11 +398,11 @@ static void inode_wait_for_writeback(struct inode *inode)
         wait_queue_head_t *wqh;
 
         wqh = bit_waitqueue(&inode->i_state, __I_SYNC);
-        do {
+         while (inode->i_state & I_SYNC) {
                 spin_unlock(&inode_lock);
                 __wait_on_bit(wqh, &wq, inode_wait, TASK_UNINTERRUPTIBLE);
                 spin_lock(&inode_lock);
-        } while (inode->i_state & I_SYNC);
+        }
 }
 
 /*
@@ -452,11 +452,9 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
 
         BUG_ON(inode->i_state & I_SYNC);
 
-        /* Set I_SYNC, reset I_DIRTY */
-        dirty = inode->i_state & I_DIRTY;
+        /* Set I_SYNC, reset I_DIRTY_PAGES */
         inode->i_state |= I_SYNC;
-        inode->i_state &= ~I_DIRTY;
-
+        inode->i_state &= ~I_DIRTY_PAGES;
         spin_unlock(&inode_lock);
 
         ret = do_writepages(mapping, wbc);
@@ -472,6 +470,15 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
                         ret = err;
         }
 
+        /*
+         * Some filesystems may redirty the inode during the writeback
+         * due to delalloc, clear dirty metadata flags right before
+         * write_inode()
+         */
+        spin_lock(&inode_lock);
+        dirty = inode->i_state & I_DIRTY;
+        inode->i_state &= ~(I_DIRTY_SYNC | I_DIRTY_DATASYNC);
+        spin_unlock(&inode_lock);
         /* Don't write the inode if only I_DIRTY_PAGES was set */
         if (dirty & (I_DIRTY_SYNC | I_DIRTY_DATASYNC)) {
                 int err = write_inode(inode, wbc);
@@ -852,6 +859,12 @@ static long wb_check_old_data_flush(struct bdi_writeback *wb)
         unsigned long expired;
         long nr_pages;
 
+        /*
+         * When set to zero, disable periodic writeback
+         */
+        if (!dirty_writeback_interval)
+                return 0;
+
         expired = wb->last_old_flush +
                         msecs_to_jiffies(dirty_writeback_interval * 10);
         if (time_before(jiffies, expired))
@@ -947,8 +960,17 @@ int bdi_writeback_task(struct bdi_writeback *wb)
                                 break;
                 }
 
-                wait_jiffies = msecs_to_jiffies(dirty_writeback_interval * 10);
-                schedule_timeout_interruptible(wait_jiffies);
+                if (dirty_writeback_interval) {
+                        wait_jiffies = msecs_to_jiffies(dirty_writeback_interval * 10);
+                        schedule_timeout_interruptible(wait_jiffies);
+                } else {
+                        set_current_state(TASK_INTERRUPTIBLE);
+                        if (list_empty_careful(&wb->bdi->work_list) &&
+                            !kthread_should_stop())
+                                schedule();
+                        __set_current_state(TASK_RUNNING);
+                }
+
                 try_to_freeze();
         }