Merge branch 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jlbec...

[safe/jmp/linux-2.6] / fs / fs-writeback.c

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index c6bf775..1a7c42c 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -242,6 +242,7 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
 /**
  * bdi_start_writeback - start writeback
  * @bdi: the backing device to write from
+ * @sb: write inodes from this super_block
  * @nr_pages: the number of pages to write
  *
  * Description:
@@ -250,9 +251,11 @@ static void bdi_sync_writeback(struct backing_dev_info *bdi,
  *   completion. Caller need not hold sb s_umount semaphore.
  *
  */
-void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages)
+void bdi_start_writeback(struct backing_dev_info *bdi, struct super_block *sb,
+                        long nr_pages)
 {
        struct wb_writeback_args args = {
+               .sb             = sb,
                .sync_mode      = WB_SYNC_NONE,
                .nr_pages       = nr_pages,
                .range_cyclic   = 1,
@@ -474,10 +477,15 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
        spin_lock(&inode_lock);
        inode->i_state &= ~I_SYNC;
        if (!(inode->i_state & (I_FREEING | I_CLEAR))) {
-               if (inode->i_state & I_DIRTY) {
+               if ((inode->i_state & I_DIRTY_PAGES) && wbc->for_kupdate) {
+                       /*
+                        * More pages get dirtied by a fast dirtier.
+                        */
+                       goto select_queue;
+               } else if (inode->i_state & I_DIRTY) {
                        /*
-                        * Someone redirtied the inode while were writing back
-                        * the pages.
+                        * At least XFS will redirty the inode during the
+                        * writeback (delalloc) and on io completion (isize).
                         */
                        redirty_tail(inode);
                } else if (mapping_tagged(mapping, PAGECACHE_TAG_DIRTY)) {
@@ -502,6 +510,7 @@ writeback_single_inode(struct inode *inode, struct writeback_control *wbc)
                                 * soon as the queue becomes uncongested.
                                 */
                                inode->i_state |= I_DIRTY_PAGES;
+select_queue:
                                if (wbc->nr_to_write <= 0) {
                                        /*
                                         * slice used up: queue for next turn
@@ -606,7 +615,6 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
                                struct writeback_control *wbc)
 {
        struct super_block *sb = wbc->sb, *pin_sb = NULL;
-       const int is_blkdev_sb = sb_is_blkdev_sb(sb);
        const unsigned long start = jiffies;    /* livelock avoidance */
 
        spin_lock(&inode_lock);
@@ -627,36 +635,11 @@ static void writeback_inodes_wb(struct bdi_writeback *wb,
                        continue;
                }
 
-               if (!bdi_cap_writeback_dirty(wb->bdi)) {
-                       redirty_tail(inode);
-                       if (is_blkdev_sb) {
-                               /*
-                                * Dirty memory-backed blockdev: the ramdisk
-                                * driver does this.  Skip just this inode
-                                */
-                               continue;
-                       }
-                       /*
-                        * Dirty memory-backed inode against a filesystem other
-                        * than the kernel-internal bdev filesystem.  Skip the
-                        * entire superblock.
-                        */
-                       break;
-               }
-
                if (inode->i_state & (I_NEW | I_WILL_FREE)) {
                        requeue_io(inode);
                        continue;
                }
 
-               if (wbc->nonblocking && bdi_write_congested(wb->bdi)) {
-                       wbc->encountered_congestion = 1;
-                       if (!is_blkdev_sb)
-                               break;          /* Skip a congested fs */
-                       requeue_io(inode);
-                       continue;               /* Skip a congested blockdev */
-               }
-
                /*
                 * Was this inode dirtied after sync_sb_inodes was called?
                 * This keeps sync from extra jobs and livelock.
@@ -748,6 +731,7 @@ static long wb_writeback(struct bdi_writeback *wb,
                .sync_mode              = args->sync_mode,
                .older_than_this        = NULL,
                .for_kupdate            = args->for_kupdate,
+               .for_background         = args->for_background,
                .range_cyclic           = args->range_cyclic,
        };
        unsigned long oldest_jif;
@@ -779,7 +763,6 @@ static long wb_writeback(struct bdi_writeback *wb,
                        break;
 
                wbc.more_io = 0;
-               wbc.encountered_congestion = 0;
                wbc.nr_to_write = MAX_WRITEBACK_PAGES;
                wbc.pages_skipped = 0;
                writeback_inodes_wb(wb, &wbc);
@@ -1200,11 +1183,28 @@ void writeback_inodes_sb(struct super_block *sb)
        nr_to_write = nr_dirty + nr_unstable +
                        (inodes_stat.nr_inodes - inodes_stat.nr_unused);
 
-       bdi_writeback_all(sb, nr_to_write);
+       bdi_start_writeback(sb->s_bdi, sb, nr_to_write);
 }
 EXPORT_SYMBOL(writeback_inodes_sb);
 
 /**
+ * writeback_inodes_sb_if_idle -       start writeback if none underway
+ * @sb: the superblock
+ *
+ * Invoke writeback_inodes_sb if no writeback is currently underway.
+ * Returns 1 if writeback was started, 0 if not.
+ */
+int writeback_inodes_sb_if_idle(struct super_block *sb)
+{
+       if (!writeback_in_progress(sb->s_bdi)) {
+               writeback_inodes_sb(sb);
+               return 1;
+       } else
+               return 0;
+}
+EXPORT_SYMBOL(writeback_inodes_sb_if_idle);
+
+/**
  * sync_inodes_sb      -       sync sb inode pages
  * @sb: the superblock
  *