On 08/14/2018 05:20 PM, Bart Van Assche wrote: > On Tue, 2018-08-14 at 09:33 +0200, Hannes Reinecke wrote: >> +const struct attribute_group *nvme_ns_id_attr_groups[] = { >> + &nvme_ns_id_attr_group, >> + NULL, /* Will be filled in by lightnvm if present */ >> + NULL, >> +}; > [ ... ] >> -void nvme_nvm_unregister_sysfs(struct nvme_ns *ns) >> -{ >> - struct nvm_dev *ndev = ns->ndev; >> - struct nvm_geo *geo = &ndev->geo; >> + return; >> >> switch (geo->major_ver_id) { >> case 1: >> - sysfs_remove_group(&disk_to_dev(ns->disk)->kobj, >> - &nvm_dev_attr_group_12); >> + nvme_ns_id_attr_groups[1] = &nvm_dev_attr_group_12; >> break; >> case 2: >> - sysfs_remove_group(&disk_to_dev(ns->disk)->kobj, >> - &nvm_dev_attr_group_20); >> + nvme_ns_id_attr_groups[1] = &nvm_dev_attr_group_20; > > This patch introduces a really ugly dependency between the NVMe core code and > the lightnvm code, namely that the lightnvm code has to know at which position > in the nvme_ns_id_attr_groups it can fill in its attribute group pointer. Have > you considered to make nvme_nvm_register_sysfs() return an attribute group > pointer such that the nvme_ns_id_attr_groups can be changed from a global into > a static array? > Wouldn't help much, as the 'nvme_ns_id_attr_groups' needs to be a global pointer anyway as it's references from drivers/nvme/host/core.c and drivers/nvme/host/multipath.c. While I have considered having nvme_nvm_register_sysfs() returning a pointer I would then have to remove the 'static' declaration from the nvm_dev_attr_group_12/20. Which I didn't really like, either. Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@xxxxxxx +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)