On Tue, Oct 30, 2007 at 04:53:17PM +0100, Karel Zak wrote: > On Sat, Oct 27, 2007 at 12:44:51PM +0200, devzero@xxxxxx wrote: > > it seems that losetup doesn`t yet honour recent kernel change (see > > http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=73285082745045bcd64333c1fbaa88f8490f2626 > > ) to allow more than 256 loop-devices. > > Ah, I remember this thing from lkml. > > > loop-device creation is dynamically now, is there already work in > > progress for support in losetup ? > > If I good remember there is not any other who how create a loop device > than by "max_loop" or "mknod /dev/loopN". It means we needn't to add > to losetup(8) any extra support for dynamically allocated loop devices. > > So, we need increment hardcoded limit of loop devices only. Right? Note, there is also list of loop devices in /sys/block, but it's useless for never used loop devices. See: # mknod /dev/loop100 b 7 100 # ls -la /dev/loop100 brw-r--r-- 1 root root 7, 100 2007-10-30 17:14 /dev/loop100 # stat /sys/block/loop100 stat: cannot stat `/sys/block/loop100': No such file or directory ^^^^^^^^^^^^^^^^^^^ Why? It doesn't make sense. Ken, cannot we create /sys/block/loopN when the device is allocated in kernel? It seems kernel creates these /sys files when the device is used first time. # losetup /dev/loop100 /mnt/store/images/fs/ext3.img # stat -t /sys/block/loop100 /sys/block/loop100 0 0 41ed 0 0 0 13994 4 0 0 1193761350 1193760920 1193760920 4096 # losetup -d /dev/loop100 # stat -t /sys/block/loop100 /sys/block/loop100 0 0 41ed 0 0 0 13994 4 0 0 1193761350 1193760920 1193760920 4096 Wow, the directory /sys/block/loop100 is persistent now. BTW, losetup -a (and -f) is useless when you have holes in list of devices, for example I have: /dev/loop0 /dev/loop1 /dev/loop2 /dev/loop3 /dev/loop4 /dev/loop5 /dev/loop6 /dev/loop7 /dev/loop100 # losetup /dev/loop100 /mnt/store/images/fs/ext3.img # losetup /dev/loop100 /dev/loop100: [0807]:21921802 (/mnt/store/images/fs/ext3.img) # losetup -a <--- nothing... loop100 is invisible. Bug :-( Karel -- Karel Zak <kzak@xxxxxxxxxx> - To unsubscribe from this list: send the line "unsubscribe util-linux-ng" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
