On 03/16/2017 08:20 AM, Matthew Wilcox wrote: > On Wed, Mar 15, 2017 at 04:51:02PM -0500, Goldwyn Rodrigues wrote: >> From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> >> >> Find out if the write will trigger a wait due to writeback. If yes, >> return -EAGAIN. >> >> This introduces a new function filemap_range_has_page() which >> returns true if the file's mapping has a page within the range >> mentioned. >> >> Return -EINVAL for buffered AIO: there are multiple causes of >> delay such as page locks, dirty throttling logic, page loading >> from disk etc. which cannot be taken care of. > > Also, this patch only touches the write path; we have a similar call to > write_and_wait_range() in generic_file_read_iter(). > This patch series is concerned with direct-write AIO paths only. -- Goldwyn