On 11/26/2012 09:35 AM, Andrzej Pietrasiewicz wrote:
In some parts of the kernel (e.g. planned configfs integration into usb gadget) there is a need to programmatically create config groups (directories) but it would be preferable to disallow creating them by the user. This is more or less what default_groups used to be for. But e.g. in the mass storage gadget, after storing the number of luns (logical units) into some configfs attribute, the corresponding lun# directories should be created, their number is not known up front so default_groups are no good for this. Example: $ echo 3> /cfg/..../mass_storage/luns causes /cfg/....../mass_storage/lun0 /cfg/....../mass_storage/lun1 /cfg/....../mass_storage/lun2
I though we did not want the luns file but instead use mkdir /cfg/....../mass_storage/lun0 mkdir /cfg/....../mass_storage/lun1 directly.
to be created. Yet $ mkdir /cfg/..../mass_storage/<any name> should not be allowed. With create_group exported it is very easily achieved: make_group and make_item are set to NULL in mass_storage's config_group, yet the kernel can create_groups at will. I kindly ask for comments. In particular, I would like to discuss if this is the right approach. A counterpart to remove config groups is also required. It is not implemented in this patch, though. What are your opinions?
Could you please at the tcm gadget? This is a mass storage gadget using target as backend and target is using configfs. Here is a snippet how you setup it: |mkdir -p $FABRIC/naa.6001405c3214b06a/tpgt_1 |mkdir $FABRIC/naa.6001405c3214b06a/tpgt_1/lun/lun_0 |mkdir $FABRIC/naa.6001405c3214b06a/tpgt_1/lun/lun_1 So you setup two luns without this patch. Would that work for you? Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
