From 0929604dd3c95ca773b9b855e375a567cc6681c1 Mon Sep 17 00:00:00 2001
From: Taylor R Campbell <riastradh@NetBSD.org>
Date: Mon, 31 Jan 2022 22:56:03 +0000
Subject: [PATCH 35/39] autoconf(9): Disentangle slightly circuitous
config_detach logic.
No functional change intended.
---
sys/kern/subr_autoconf.c | 37 +++++++++++++++++++++++++------------
1 file changed, 25 insertions(+), 12 deletions(-)
diff --git a/sys/kern/subr_autoconf.c b/sys/kern/subr_autoconf.c
index 03afc7f54b55..5c1c865785f8 100644
--- a/sys/kern/subr_autoconf.c
+++ b/sys/kern/subr_autoconf.c
@@ -2029,6 +2029,11 @@ config_detach(device_t dev, int flags)
alldevs_nwrite++;
mutex_exit(&alldevs_lock);
+ /*
+ * Call the driver's .ca_detach function, unless it has none or
+ * we are skipping it because it's unforced shutdown time and
+ * the driver didn't ask to detach on shutdown.
+ */
if (!detachall &&
(flags & (DETACH_SHUTDOWN|DETACH_FORCE)) == DETACH_SHUTDOWN &&
(dev->dv_flags & DVF_DETACH_SHUTDOWN) == 0) {
@@ -2041,31 +2046,39 @@ config_detach(device_t dev, int flags)
/*
* If it was not possible to detach the device, then we either
* panic() (for the forced but failed case), or return an error.
- *
- * If it was possible to detach the device, ensure that the
- * device is deactivated.
*/
- if (rv == 0) {
- config_detach_commit(dev);
- dev->dv_flags &= ~DVF_ACTIVE; /* XXXSMP */
- } else if ((flags & DETACH_FORCE) == 0) {
+ if (rv) {
/*
- * Detach failed -- likely EBUSY. Driver must not have
- * called config_detach_commit.
+ * Detach failed -- likely EOPNOTSUPP or EBUSY. Driver
+ * must not have called config_detach_commit.
*/
KASSERTMSG(!dev->dv_detached,
"%s committed to detaching and then backed out",
device_xname(dev));
+ if (flags & DETACH_FORCE) {
+ panic("config_detach: forced detach of %s failed (%d)",
+ device_xname(dev), rv);
+ }
goto out;
- } else {
- panic("config_detach: forced detach of %s failed (%d)",
- device_xname(dev), rv);
}
/*
* The device has now been successfully detached.
*/
+ /*
+ * If .ca_detach didn't commit to detach, then do that for it.
+ * This wakes any pending device_lookup_acquire calls so they
+ * will fail.
+ */
+ config_detach_commit(dev);
+
+ /*
+ * If it was possible to detach the device, ensure that the
+ * device is deactivated.
+ */
+ dev->dv_flags &= ~DVF_ACTIVE; /* XXXSMP */
+
/*
* Wait for all device_lookup_acquire references -- mostly, for
* all attempts to open the device -- to drain. It is the