git: 96e500a3f9f0 - main - hda: Push giant / newbus topo lock down a layer

The branch main has been updated by imp:

URL: https://cgit.FreeBSD.org/src/commit/?id=96e500a3f9f0e317875b5d5c2097df804106bc3f

commit 96e500a3f9f0e317875b5d5c2097df804106bc3f
Author:     Warner Losh <imp@FreeBSD.org>
AuthorDate: 2021-12-09 23:52:55 +0000
Commit:     Warner Losh <imp@FreeBSD.org>
CommitDate: 2021-12-10 00:04:58 +0000

    hda: Push giant / newbus topo lock down a layer
    
    Rather than picking up Giant at the start of these sysctl handlers, push
    acquiring Giant down a layer to protect walking the children and also
    to add/delete children for the reconfigure.
    
    Sponsored by:           Netflix
    Reviewed by:            mav, jhb
    Differential Revision:  https://reviews.freebsd.org/D33057
---
 sys/dev/sound/pci/hda/hdaa.c | 13 +++++++++++--
 sys/dev/sound/pci/hda/hdac.c | 14 +++++++++++---
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/sys/dev/sound/pci/hda/hdaa.c b/sys/dev/sound/pci/hda/hdaa.c
index 82c309996d75..ddc22c3bc139 100644
--- a/sys/dev/sound/pci/hda/hdaa.c
+++ b/sys/dev/sound/pci/hda/hdaa.c
@@ -6463,16 +6463,25 @@ hdaa_sysctl_reconfig(SYSCTL_HANDLER_ARGS)
 	HDA_BOOTHVERBOSE(
 		device_printf(dev, "Reconfiguration...\n");
 	);
-	if ((error = device_delete_children(dev)) != 0)
+
+	bus_topo_lock();
+
+	if ((error = device_delete_children(dev)) != 0) {
+		bus_topo_unlock();
 		return (error);
+	}
 	hdaa_lock(devinfo);
 	hdaa_unconfigure(dev);
 	hdaa_configure(dev);
 	hdaa_unlock(devinfo);
 	bus_generic_attach(dev);
+	bus_topo_unlock();
 	HDA_BOOTHVERBOSE(
 		device_printf(dev, "Reconfiguration done\n");
 	);
+
+	bus_topo_unlock();
+
 	return (0);
 }
 
@@ -6669,7 +6678,7 @@ hdaa_attach(device_t dev)
 	    devinfo, 0, hdaa_sysctl_gpo_config, "A", "GPO configuration");
 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(dev),
 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
-	    "reconfig", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
+	    "reconfig", CTLTYPE_INT | CTLFLAG_RW,
 	    dev, 0, hdaa_sysctl_reconfig, "I", "Reprocess configuration");
 	SYSCTL_ADD_INT(device_get_sysctl_ctx(dev),
 	    SYSCTL_CHILDREN(device_get_sysctl_tree(dev)), OID_AUTO,
diff --git a/sys/dev/sound/pci/hda/hdac.c b/sys/dev/sound/pci/hda/hdac.c
index 5d3f1d85a2ad..058eb63e268d 100644
--- a/sys/dev/sound/pci/hda/hdac.c
+++ b/sys/dev/sound/pci/hda/hdac.c
@@ -1387,12 +1387,20 @@ sysctl_hdac_pindump(SYSCTL_HANDLER_ARGS)
 		return (0);
 	}
 
-	if ((err = device_get_children(dev, &devlist, &devcount)) != 0)
+	bus_topo_lock();
+
+	if ((err = device_get_children(dev, &devlist, &devcount)) != 0) {
+		bus_topo_unlock();
 		return (err);
+	}
+
 	hdac_lock(sc);
 	for (i = 0; i < devcount; i++)
 		HDAC_PINDUMP(devlist[i]);
 	hdac_unlock(sc);
+
+	bus_topo_unlock();
+
 	free(devlist, M_TEMP);
 	return (0);
 }
@@ -1607,11 +1615,11 @@ hdac_attach2(void *arg)
 
 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(sc->dev),
 	    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)), OID_AUTO,
-	    "pindump", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc->dev,
+	    "pindump", CTLTYPE_INT | CTLFLAG_RW, sc->dev,
 	    sizeof(sc->dev), sysctl_hdac_pindump, "I", "Dump pin states/data");
 	SYSCTL_ADD_PROC(device_get_sysctl_ctx(sc->dev),
 	    SYSCTL_CHILDREN(device_get_sysctl_tree(sc->dev)), OID_AUTO,
-	    "polling", CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT, sc->dev,
+	    "polling", CTLTYPE_INT | CTLFLAG_RW, sc->dev,
 	    sizeof(sc->dev), sysctl_hdac_polling, "I", "Enable polling mode");
 }