tree cdff776596fa79bfc9c2f2baf7aa59470dc29aec
parent aabe51364f44681cbd83fb1c27ef7d3dbe567c45
author Jaegeuk Kim <jaegeuk.kim@samsung.com> 1382589094 +0900
committer Jaegeuk Kim <jaegeuk.kim@samsung.com> 1382687677 +0900

f2fs: reclaim prefree segments periodically

Previously, f2fs postpones reclaiming prefree segments into free segments
as much as possible.
However, if user writes and deletes a bunch of data without any sync or fsync
calls, some flash storages can suffer from garbage collections.

So, this patch adds the reclaiming codes to f2fs_write_node_pages and background
GC thread.

If there are a lot of prefree segments, let's do checkpoint so that f2fs
submits discard commands for the prefree regions to the flash storage.

Signed-off-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>