On Fri, May 08 2020 at 3:22pm -0400, kj@xxxxxxxxxx <kj@xxxxxxxxxx> wrote: > On Thu, May 7, 2020, at 21:12, Chaitanya Kulkarni wrote: > > On 05/07/2020 04:06 PM, Kjetil Orbekk wrote: > > > + if (tio->error) > > > + atomic_inc(&md->ioerr_cnt); > > > > Given that there are so many errors how would user know what > > kind of error is generated and how many times? > > The intended use case is to provide an easy way to check if errors > have occurred at all, and then the user needs to investigate using > other means. I replied with more detail to Alasdair's email. But most operations initiated by the user that fail will be felt by the upper layer that the user is interfacing with. Only exception that springs to mind is dm-writecache's writeback that occurs after writes have already been acknowledged back to the upper layers -- in that case dm-writecache provides an error flag that is exposed via writecache_status. Anyway, just not seeing why you need a upper-layer use-case agnostic flag to know an error occurred in DM. That layers that interface with the DM device will have been notified of all errors. And why just for DM devices? Why not all block devices (in which case DM would get this feature "for free")? Mike -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
