| Issue 57: | Return values of dm ioctl, why ' -1 ' | |
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The dm ioctl is returning ' -1 ' even if everything is correct. is this the defined behaviour. Will it be changed or the user space code has to take care of this What other values can it return like 0 ,1 What if a error ocurred there and the OHSM cannot proceed. Moreover the Size of the mapper table is fixed i suppose can it impose problems
Feb 1, 2009
Project Member
#1
sandeepksinha
Owner:
sandeepksinha
Feb 1, 2009
We have fixed that the maximum number of devices we support is 10 maximum number of tiers we support is 10 The SAM table is working on this assumption The problem can be resolved in the user space itself IF AND ONLY IF the lvm user wants to use is made using the interface and scripts we are providing We can check out there itself the number of devices entered and puke error if it does not suit us. But Wat if the user wants to use a LVM which he has created He can have N number of device and specifically greater that 10 In that case the size of mapper_table is also fixed and is harcoded as 10 the nr_targets value will be greater than 10 and thus mapper_table will not have information about any last few devices ??? quite serious i suppose Solution to it is -> make the mapper_table dynamic ( not preffered by me as it may be time consuming) -> send an error number through the ioctl interface "say 5" which the user space will identify as "Number of Devices greater than supported" and puke an error and also make the NUMBER OF DISKS supported as 20 or 25 or any suitable value you feel
Feb 1, 2009
Hi Rishi , Well you are right about dm ioctl that it is returning -1. I would soon fix the return values for dm-ioctl. After fixing the return values for dm-ioctl, the problem that you had mention that if the count exceeds the maximum defined limit would get solved.
Feb 1, 2009
Assigning it to Vineet, as he is looking into this issue. Vineet finish off this asap and close the issue.
Owner:
checkout.vineet
Feb 2, 2009
Vineet NO UPDATES ?????????????????????????????? ??????????????????????????????
Feb 2, 2009
The issue has been fixed on error it returns -1 on success it returns 0
Status:
Fixed
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