Merge tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg...

Pull writeback fix from Wu Fengguang:
 "A trivial writeback fix"

* tag 'writeback-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: Do not sort b_io list only because of block device inode

diff --git a/fs/block_dev.c b/fs/block_dev.c
index c3549ed..1e86823 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -592,7 +592,7 @@ static struct block_device *bd_acquire(struct inode *inode)
        return bdev;
 }
 
-static inline int sb_is_blkdev_sb(struct super_block *sb)
+int sb_is_blkdev_sb(struct super_block *sb)
 {
        return sb == blockdev_superblock;
 }

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 30f6f27..9f4935b 100644 (file)
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -69,7 +69,7 @@ static inline struct backing_dev_info *inode_to_bdi(struct inode *inode)
 {
        struct super_block *sb = inode->i_sb;
 
-       if (strcmp(sb->s_type->name, "bdev") == 0)
+       if (sb_is_blkdev_sb(sb))
                return inode->i_mapping->backing_dev_info;
 
        return sb->s_bdi;
@@ -251,11 +251,13 @@ static int move_expired_inodes(struct list_head *delaying_queue,
                if (work->older_than_this &&
                    inode_dirtied_after(inode, *work->older_than_this))
                        break;
+               list_move(&inode->i_wb_list, &tmp);
+               moved++;
+               if (sb_is_blkdev_sb(inode->i_sb))
+                       continue;
                if (sb && sb != inode->i_sb)
                        do_sb_sort = 1;
                sb = inode->i_sb;
-               list_move(&inode->i_wb_list, &tmp);
-               moved++;
        }
 
        /* just one sb in list, splice to dispatch_queue and we're done */

diff --git a/include/linux/fs.h b/include/linux/fs.h
index a4acd3c..3f40547 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2069,6 +2069,7 @@ extern struct super_block *freeze_bdev(struct block_device *);
 extern void emergency_thaw_all(void);
 extern int thaw_bdev(struct block_device *bdev, struct super_block *sb);
 extern int fsync_bdev(struct block_device *);
+extern int sb_is_blkdev_sb(struct super_block *sb);
 #else
 static inline void bd_forget(struct inode *inode) {}
 static inline int sync_blockdev(struct block_device *bdev) { return 0; }
@@ -2088,6 +2089,11 @@ static inline int thaw_bdev(struct block_device *bdev, struct super_block *sb)
 static inline void iterate_bdevs(void (*f)(struct block_device *, void *), void *arg)
 {
 }
+
+static inline int sb_is_blkdev_sb(struct super_block *sb)
+{
+       return 0;
+}
 #endif
 extern int sync_filesystem(struct super_block *);
 extern const struct file_operations def_blk_fops;