On Tue, 2010-06-01 at 12:47 -0400, Chris Mason wrote: > On Tue, Jun 01, 2010 at 10:29:30AM -0600, Matthew Wilcox wrote: > > On Tue, Jun 01, 2010 at 09:49:51AM -0400, Chris Mason wrote: > > > > I agree that a block based retry would close all the holes ... it just > > > > doesn't look elegant to me that the fs will already be repeating the I/O > > > > if it changed the page and so will block. > > > > > > We might not ever repeat the IO. We might change the page, write it, > > > change it again, truncate the file and toss the page completely. > > > > Why does it matter that it was never written in that case? > > It matters is the storage layer is going to wait around for the block to > be written again with a correct crc. Actually, I wasn't advocating that. I think block should return a guard mismatch error. I think somewhere in filesystem writeout is the place to decide whether the error was self induced or systematic. For self induced errors (as long as we can detect them) I think we can just forget about it ... if the changed page is important, the I/O request gets repeated (modulo the problem of too great a frequency of changes leading to us never successfully writing it) or it gets dropped because the file was truncated or the data deleted for some other reason. James -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
