X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=fs%2Ffs-writeback.c;h=ae45f77765c0ee65a647fc81c899315de2f0862f;hb=13a6ddb08e58a1bd344da7898c4e2f13bdf18c2f;hp=3fe782d70a71d5f89ed2b65016d7fda322016701;hpb=2d544564f9954860235db97df2e549a66c61f557;p=linux-2.6

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 3fe782d70a..ae45f77765 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -25,6 +25,45 @@
 #include <linux/buffer_head.h>
 #include "internal.h"
 
+
+/**
+ * writeback_acquire - attempt to get exclusive writeback access to a device
+ * @bdi: the device's backing_dev_info structure
+ *
+ * It is a waste of resources to have more than one pdflush thread blocked on
+ * a single request queue.  Exclusion at the request_queue level is obtained
+ * via a flag in the request_queue's backing_dev_info.state.
+ *
+ * Non-request_queue-backed address_spaces will share default_backing_dev_info,
+ * unless they implement their own.  Which is somewhat inefficient, as this
+ * may prevent concurrent writeback against multiple devices.
+ */
+static int writeback_acquire(struct backing_dev_info *bdi)
+{
+	return !test_and_set_bit(BDI_pdflush, &bdi->state);
+}
+
+/**
+ * writeback_in_progress - determine whether there is writeback in progress
+ * @bdi: the device's backing_dev_info structure.
+ *
+ * Determine whether there is writeback in progress against a backing device.
+ */
+int writeback_in_progress(struct backing_dev_info *bdi)
+{
+	return test_bit(BDI_pdflush, &bdi->state);
+}
+
+/**
+ * writeback_release - relinquish exclusive writeback access against a device.
+ * @bdi: the device's backing_dev_info structure
+ */
+static void writeback_release(struct backing_dev_info *bdi)
+{
+	BUG_ON(!writeback_in_progress(bdi));
+	clear_bit(BDI_pdflush, &bdi->state);
+}
+
 /**
  *	__mark_inode_dirty -	internal function
  *	@inode: inode to mark
@@ -284,7 +323,17 @@ __sync_single_inode(struct inode *inode, struct writeback_control *wbc)
 				 * soon as the queue becomes uncongested.
 				 */
 				inode->i_state |= I_DIRTY_PAGES;
-				requeue_io(inode);
+				if (wbc->nr_to_write <= 0) {
+					/*
+					 * slice used up: queue for next turn
+					 */
+					requeue_io(inode);
+				} else {
+					/*
+					 * somehow blocked: retry later
+					 */
+					redirty_tail(inode);
+				}
 			} else {
 				/*
 				 * Otherwise fully redirty the inode so that
@@ -468,8 +517,12 @@ sync_sb_inodes(struct super_block *sb, struct writeback_control *wbc)
 		iput(inode);
 		cond_resched();
 		spin_lock(&inode_lock);
-		if (wbc->nr_to_write <= 0)
+		if (wbc->nr_to_write <= 0) {
+			wbc->more_io = 1;
 			break;
+		}
+		if (!list_empty(&sb->s_more_io))
+			wbc->more_io = 1;
 	}
 	return;		/* Leave any unwritten inodes on s_io */
 }
@@ -501,8 +554,7 @@ writeback_inodes(struct writeback_control *wbc)
 	might_sleep();
 	spin_lock(&sb_lock);
 restart:
-	sb = sb_entry(super_blocks.prev);
-	for (; sb != sb_entry(&super_blocks); sb = sb_entry(sb->s_list.prev)) {
+	list_for_each_entry_reverse(sb, &super_blocks, s_list) {
 		if (sb_has_dirty_inodes(sb)) {
 			/* we're making our own get_super here */
 			sb->s_count++;
@@ -567,10 +619,8 @@ static void set_sb_syncing(int val)
 {
 	struct super_block *sb;
 	spin_lock(&sb_lock);
-	sb = sb_entry(super_blocks.prev);
-	for (; sb != sb_entry(&super_blocks); sb = sb_entry(sb->s_list.prev)) {
+	list_for_each_entry_reverse(sb, &super_blocks, s_list)
 		sb->s_syncing = val;
-	}
 	spin_unlock(&sb_lock);
 }
 
@@ -644,7 +694,7 @@ int write_inode_now(struct inode *inode, int sync)
 	int ret;
 	struct writeback_control wbc = {
 		.nr_to_write = LONG_MAX,
-		.sync_mode = WB_SYNC_ALL,
+		.sync_mode = sync ? WB_SYNC_ALL : WB_SYNC_NONE,
 		.range_start = 0,
 		.range_end = LLONG_MAX,
 	};
@@ -736,43 +786,4 @@ int generic_osync_inode(struct inode *inode, struct address_space *mapping, int
 
 	return err;
 }
-
 EXPORT_SYMBOL(generic_osync_inode);
-
-/**
- * writeback_acquire: attempt to get exclusive writeback access to a device
- * @bdi: the device's backing_dev_info structure
- *
- * It is a waste of resources to have more than one pdflush thread blocked on
- * a single request queue.  Exclusion at the request_queue level is obtained
- * via a flag in the request_queue's backing_dev_info.state.
- *
- * Non-request_queue-backed address_spaces will share default_backing_dev_info,
- * unless they implement their own.  Which is somewhat inefficient, as this
- * may prevent concurrent writeback against multiple devices.
- */
-int writeback_acquire(struct backing_dev_info *bdi)
-{
-	return !test_and_set_bit(BDI_pdflush, &bdi->state);
-}
-
-/**
- * writeback_in_progress: determine whether there is writeback in progress
- * @bdi: the device's backing_dev_info structure.
- *
- * Determine whether there is writeback in progress against a backing device.
- */
-int writeback_in_progress(struct backing_dev_info *bdi)
-{
-	return test_bit(BDI_pdflush, &bdi->state);
-}
-
-/**
- * writeback_release: relinquish exclusive writeback access against a device.
- * @bdi: the device's backing_dev_info structure
- */
-void writeback_release(struct backing_dev_info *bdi)
-{
-	BUG_ON(!writeback_in_progress(bdi));
-	clear_bit(BDI_pdflush, &bdi->state);
-}