On Sat, Aug 20, 2011 at 07:29:42PM -0700, Allison Henderson wrote: > + /* If the range is block aligned, unmap */ > + if (range_to_discard == blocksize) { > + clear_buffer_dirty(bh); > + bh->b_bdev = NULL; > + clear_buffer_mapped(bh); > + clear_buffer_req(bh); > + clear_buffer_new(bh); > + clear_buffer_delay(bh); > + clear_buffer_unwritten(bh); > + clear_buffer_uptodate(bh); > + ClearPageUptodate(page); Is this ClearPageUptodate() necessary? If the page is uptodate, and we've zero'ed out the relevant space, why do we need to force the page to read in from disk again? (In fact, if we want to avoid forcing the whole punched region to be written to disk, we'll need to get rid of the ClearPageUptodate() sooner or later --- and I'm not sure I see why it's needed now. Am I missing something?) - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html