> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Dan Williams > Sent: Thursday, January 13, 2011 6:28 PM > To: Kwolek, Adam > Cc: neilb@xxxxxxx; linux-raid@xxxxxxxxxxxxxxx; Neubauer, Wojciech; > Ciechanowski, Ed > Subject: Re: open_dev_excl in reshape_container() fails > > 2011/1/13 Kwolek, Adam <adam.kwolek@xxxxxxxxx>: > > Hi, > > > > I've got a problem using open_dev_excl() in reshape_container(), it > fails. This functions goes down > > and calls open() with flags O_DIRECT| O_RDWR| O_EXCL. > > It fails in reshape_container(), ealier in Grow_reshape() exactly the > same test call to open_dev_excl() succeed. > > Between test open and open in reshape_container() there is no other > open() performed (or other i/o operation that can cause problem). > > It not depends on mdmon action because it is the same for raid5 and > raid0. > > Function open_dev() works, and I'm using it as workaround. > > > > In man pages for open() is told that O_EXCL flag should be used with > O_CREAT flag only. > > I've read in manual for open() also: "If O_EXCL is set and O_CREAT is > not set, the result is undefined" > > Right, it is undefined with respect to Posix, but for Linux O_EXCL on > a block device without O_CREAT is defined to bd_claim the block > device. > > http://www.kernel.org/doc/man-pages/online/pages/man2/open.2.html > > The second call to open_dev_excl is a bug, by definition you can't > exclusive open twice. Can you reuse the fd established in > Grow_reshape? > > -- > Dan There is no second open. My test call to open_dev_excl() is closed at once ;), and it is used to detect where I can successfully open device and if there is any duplicated open. There is no other open that can block open_dev_excl() in reshape_container() (when monitor is absent also), or I was unable to find it. Handle cannot be reused, because in Grow_reshape() container is opened and in reshape_container() all arrays Are opened one by one. BR Adam > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" > in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
