tree 5f06f6c83413ca2fc7aec85ba0811a8c91904097
parent cb44921a09221f0a90217b44044448f63190f3e5
author Chris Mason <chris.mason@oracle.com> 1288365377 -0400
committer Chris Mason <chris.mason@oracle.com> 1288365929 -0400

Add new functions for triggering inode writeback

When btrfs is running low on metadata space, it needs to force delayed
allocation pages to disk.  It currently does this with a suboptimal walk
of a private list of inodes with delayed allocation, and it would be
much better if we used the generic flusher threads.

writeback_inodes_sb_if_idle would be ideal, but it waits for the flusher
thread to start IO on all the dirty pages in the FS before it returns.
This adds variants of writeback_inodes_sb* that allow the caller to
control how many pages get sent down.

Signed-off-by: Chris Mason <chris.mason@oracle.com>