On Mon, 23 Oct 2006, Dave Hylands wrote: > Hi Todd, > > Replying to the list this time... > > > The problem is that the changes I make to the files on the desktop > > are not immediately reflected in /mnt/loop on the gumstix. If I > > 'cd' into /mnt/loop on the gumstix I see things only as they were > > orginally; there are no file additions, deletions, or edits. I can > > monitor the backing storage (/root/data/backing_file) using the > > 'stat(2)' routine and confirm that it is being updated as I make > > changes on the XP desktop, but these changes are not showing up in > > /mnt/loop. My gumstix-resident application needs immediate access to > > changes. The changes are there and they are persistent -- I just can't > > see them. To actually see the changes in /mnt/loop I must reboot the > > gumstix, and repeat the various 'modprobe', 'losetup', and 'mount' > > operations. > > > At the bottom of the page you referenced it says this (in the section > titled: Accessing the backing storage from the gadget): > It is possible to manipulate the data in the backing storage from the > gadget (even to add the filesystem). Don't do this while the gadget is > connected to a USB host! > > So you can't have your gadget seeing the data at the same time as XP > is (at least that's the way I understand how this works). The problem > is that XP has full control at the sector level and may have sectors > cached. When you try to access through the loop device, your gadget > thinks that it owns the sectors and it may have data cached. Trying to > have both access the data at the same time is a recipie for data > corruption and loss.
That's right. You should never have /dev/loop0 mounted while the gadget is connected to a host. If you need the files to be simultaneously visible on both sides then you can't use g_file_storage. An alternative is to use g_ether -- or even a regular ethernet connection -- and do normal file-sharing, such as Samba. Alan Stern ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Linux-usb-users@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
