Hello. Andrew Morton wrote: > reiser4 is currently disabled in -mm (via reiser4-disable.patch) > because recent changes to fs/fs/writeback.c wrecked the build. I fixed > it about ten times as the underlying code was churning, then gave up. It > would be nice if you take a look at that sometime please. > > I have taken a look at fs/fs-writeback.c and found that per-superblock flushing interface is eliminated. However migrating to per-bdi flushing model doesn't necessarily means that such interface doesn't exist or is not needed anymore. Flushing in accordance with the scheme "data-inode- data-inode-..." would be very suboptimal for reiser4. Also xfs people were unhappy with such flushing model: http://article.gmane.org/gmane.linux.file-systems/30153 Moreover, current stuff doesn't look fine. Why do we pin/unpin superblock for every inode? It would be more reasonable to pin it for the whole group of inodes and call a flushing handler for them. The patch 4 introduces such handler writeback_sb_inodes (which resembles dropped sync_sb_inodes, the difference is that the newer version doesn't flush necessarily all inodes of the superblock). Please, consider pushing this patch to mainline. The patch 5 adds a super operation .writeback_inodes (former .sync_inodes) which allows a file system to make optimizations. It can happen that reiser4 will flush a bit more inodes then generic implementation suggests. "a bit more" doesn't mean "all dirty inodes of the superblock" (see a comment about atoms in the header of patch 6). Finally, some file systems have its own means for periodical writeout of dirty data. Since b_io contains inodes of many superblocks we need to evict our inodes back to dirty list when flushing is going on with for_kupdate flag installed. The new library function writeback_skip_sb_inodes() provides such possibility. Please, apply. Thanks, Edward. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
