On Tue, Jul 05, 2022 at 10:41:52AM -0600, Logan Gunthorpe wrote: > Using sysfs means we don't need all the messy callbacks from the nvme > driver, which is a plus. But I'm not sure how we'd get or unmap the > mapping of a sysfs file or avoid the anonymous inode. Seems with the > existing PCI resources, it uses an bin_attribute->f_mapping() callback > to pass back the iomem_get_mapping() mapping on file open. > revoke_iomem() is then used to nuke the VMAs. I don't think we can use > the same infrastructure here as that would add a dependency on > CONFIG_IO_STRICT_DEVMEM; which would be odd. And I'm not sure whether > there is a better way. Why can't we do the revoke on the actual sysfs inode?
