Module Name: src Committed By: riastradh Date: Mon Mar 28 12:38:15 UTC 2022
Modified Files: src/sys/kern: subr_autoconf.c src/sys/sys: device.h Log Message: autoconf(9): New function config_detach_commit. When a driver's .ca_detach function has committed to detaching -- it definitely won't back out with EBUSY, for instance -- it can call this to wake all pending calls to device_lookup_acquire and make them fail immediately. This is necessary to break a deadlock if the device_lookup_acquire calls happen inside I/O operations which the driver's .ca_detach function waits for the completion of -- without config_detach_commit, I/O operations would be stuck in device_lookup_acquire waiting for .ca_detach and .ca_detach would be stuck waiting for I/O operations to return. Most drivers won't need to call this: for autoconf drivers used the traditional way by devsw for userland device nodes, the .ca_detach routine uses vdevgone, and we will arrange to make vdevgone call config_detach_commit automagically in such drivers anyway. XXX kernel ABI change to struct device requires bump -- later change will make struct device opaque to ABI, but we're not there yet To generate a diff of this commit: cvs rdiff -u -r1.298 -r1.299 src/sys/kern/subr_autoconf.c cvs rdiff -u -r1.180 -r1.181 src/sys/sys/device.h Please note that diffs are not public domain; they are subject to the copyright notices on the relevant files.