2011/7/11 João Eduardo Luís <jecluis@xxxxxxxxx>: > Hello. > > Am I reading the code the wrong way, or is the 'last_index' variable in '__btrfs_buffered_write()' (and previously used in 'btrfs_file_aio_write()') irrelevant? > > It appears to just be used in 'prepare_pages()', passed as an argument, but never actually used by this function. > > Furthermore, I'm not sure what is intended with this variable, but if the idea is to assign it with the last page in the range, then I would say that instead of > >> last_index = (pos + iov_iter_count(i)) >> PAGE_CACHE_SHIFT; > > it should be > >> last_index = (pos + iov_iter_count(i) - 1) >> PAGE_CACHE_SHIFT; > > Then again, I may be missing something. > > Cheers. > I came to the same conclusion a few months ago when looking at a bug in the same area of code. The calculation appears to be wrong, but since it's not used anywhere, you can't say for certain. :) I just haven't gotten around to testing a patch to confirm the hypothesis. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
