[PATCH] separate bdi congestion functions from queue congestion functions

Separate out the concept of "queue congestion" from "backing-dev congestion".
Congestion is a backing-dev concept, not a queue concept.

The blk_* congestion functions are retained, as wrappers around the core
backing-dev congestion functions.

This proper layering is needed so that NFS can cleanly use the congestion
functions, and so that CONFIG_BLOCK=n actually links.

Cc: "Thomas Maier" <balagi@justmail.de>
Cc: "Jens Axboe" <jens.axboe@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: David Howells <dhowells@redhat.com>
Cc: Peter Osterlund <petero2@telia.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/fat/file.c b/fs/fat/file.c
index f4b8f8b..8337451 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -13,6 +13,7 @@
 #include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
+#include <linux/backing-dev.h>
 #include <linux/blkdev.h>
 
 int fat_generic_ioctl(struct inode *inode, struct file *filp,
@@ -118,7 +119,7 @@
 	if ((filp->f_mode & FMODE_WRITE) &&
 	     MSDOS_SB(inode->i_sb)->options.flush) {
 		fat_flush_inodes(inode->i_sb, inode, NULL);
-		blk_congestion_wait(WRITE, HZ/10);
+		congestion_wait(WRITE, HZ/10);
 	}
 	return 0;
 }
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index f6675d2..ca92ac3 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -57,6 +57,8 @@
 #include <linux/nfs_fs.h>
 #include <linux/nfs_mount.h>
 #include <linux/nfs_page.h>
+#include <linux/backing-dev.h>
+
 #include <asm/uaccess.h>
 #include <linux/smp_lock.h>
 
@@ -395,7 +397,7 @@
 out:
 	clear_bit(BDI_write_congested, &bdi->state);
 	wake_up_all(&nfs_write_congestion);
-	writeback_congestion_end();
+	congestion_end(WRITE);
 	return err;
 }
 
diff --git a/fs/reiserfs/journal.c b/fs/reiserfs/journal.c
index ad8cbc4..85ce232 100644
--- a/fs/reiserfs/journal.c
+++ b/fs/reiserfs/journal.c
@@ -53,6 +53,7 @@
 #include <linux/workqueue.h>
 #include <linux/writeback.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 
 /* gets a struct reiserfs_journal_list * from a list head */
 #define JOURNAL_LIST_ENTRY(h) (list_entry((h), struct reiserfs_journal_list, \
@@ -970,7 +971,7 @@
 	DEFINE_WAIT(wait);
 	struct reiserfs_journal *j = SB_JOURNAL(s);
 	if (atomic_read(&j->j_async_throttle))
-		blk_congestion_wait(WRITE, HZ / 10);
+		congestion_wait(WRITE, HZ / 10);
 	return 0;
 }
 
diff --git a/fs/xfs/linux-2.6/kmem.c b/fs/xfs/linux-2.6/kmem.c
index d597375..004baf6 100644
--- a/fs/xfs/linux-2.6/kmem.c
+++ b/fs/xfs/linux-2.6/kmem.c
@@ -21,6 +21,7 @@
 #include <linux/highmem.h>
 #include <linux/swap.h>
 #include <linux/blkdev.h>
+#include <linux/backing-dev.h>
 #include "time.h"
 #include "kmem.h"
 
@@ -53,7 +54,7 @@
 			printk(KERN_ERR "XFS: possible memory allocation "
 					"deadlock in %s (mode:0x%x)\n",
 					__FUNCTION__, lflags);
-		blk_congestion_wait(WRITE, HZ/50);
+		congestion_wait(WRITE, HZ/50);
 	} while (1);
 }
 
@@ -131,7 +132,7 @@
 			printk(KERN_ERR "XFS: possible memory allocation "
 					"deadlock in %s (mode:0x%x)\n",
 					__FUNCTION__, lflags);
-		blk_congestion_wait(WRITE, HZ/50);
+		congestion_wait(WRITE, HZ/50);
 	} while (1);
 }
 
diff --git a/fs/xfs/linux-2.6/xfs_buf.c b/fs/xfs/linux-2.6/xfs_buf.c
index 9bbadaf..db5f5a3 100644
--- a/fs/xfs/linux-2.6/xfs_buf.c
+++ b/fs/xfs/linux-2.6/xfs_buf.c
@@ -30,6 +30,7 @@
 #include <linux/hash.h>
 #include <linux/kthread.h>
 #include <linux/migrate.h>
+#include <linux/backing-dev.h>
 #include "xfs_linux.h"
 
 STATIC kmem_zone_t *xfs_buf_zone;
@@ -395,7 +396,7 @@
 
 			XFS_STATS_INC(xb_page_retries);
 			xfsbufd_wakeup(0, gfp_mask);
-			blk_congestion_wait(WRITE, HZ/50);
+			congestion_wait(WRITE, HZ/50);
 			goto retry;
 		}