Hi all, Here is a first legitimate pass at COW fork speculative preallocation. Updates from the previously posted rfc are noted below. Highlights are inclusion of the COW fork fiemap patch, support for throttling preallocation on low free space conditions and refactoring tweaks to create a separate helper for the data fork -> COW fork lookup sequence. Other changes are minor updates based on review of the rfc. Note that I decided to retain patch 3 as an independent patch and hopefully explain it a bit better. We can still squash it into the subsequent patch if warranted, however. The xfs_io patch to take advantage of COW fork fiemap is available here: http://www.spinics.net/lists/linux-xfs/msg01710.html This survives xfstests with the exception of generic/305, which appears to just be a case of hardcoded accounting in the golden output file changing due to preallocation. I'll have to figure out the best way to deal with that (a preceding eofb scan perhaps?). Thoughts, reviews, flames appreciated. Brian v1: - Rebase onto for-next (new iext lookup helpers). - Split off speculative prealloc refactor patches into separate series. - Prepend the COW fork fiemap patch. - Create xfs_iomap_search_extents() helper for data/COW fork extent lookup. - Reuse xfs_iomap_prealloc_size() to incorporate prealloc throttling. - Added patch to reclaim cowblocks on write failure due to ENOSPC. rfc: http://www.spinics.net/lists/linux-xfs/msg02152.html Brian Foster (6): xfs: fiemap support for cow fork xfs: refactor iomap delalloc existing extent search into helper xfs: logically separate iomap range from allocation range xfs: reuse iomap delalloc code for COW fork reservation xfs: free cowblocks and retry on buffered write ENOSPC xfs: implement basic COW fork speculative preallocation fs/xfs/xfs_file.c | 1 + fs/xfs/xfs_iomap.c | 315 +++++++++++++++++++++++++++++++++----------- fs/xfs/xfs_iomap.h | 1 + fs/xfs/xfs_iops.c | 4 + include/uapi/linux/fiemap.h | 1 + 5 files changed, 244 insertions(+), 78 deletions(-) -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-xfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
