Provide a device name in the sysctl tree for programs to query the

state of crashdump target devices.

This will be used to add a "-l" (ell) flag to dumpon(8) to list the
currently configured dumpdev.

Reviewed by:	phk

4 files changed, 16 insertions, 6 deletions

diff --git a/sys/dev/null/null.c b/sys/dev/null/null.c
index 0fe46fa..c1208c11 100644
--- a/sys/dev/null/null.c
+++ b/sys/dev/null/null.c
@@ -91,7 +91,7 @@ null_ioctl(struct cdev *dev __unused, u_long cmd, caddr_t data __unused,
 	case DIOCSKERNELDUMP:
 		error = priv_check(td, PRIV_SETDUMPER);
 		if (error == 0)
-			error = set_dumper(NULL);
+			error = set_dumper(NULL, NULL);
 		break;
 	case FIONBIO:
 		break;
diff --git a/sys/geom/geom_dev.c b/sys/geom/geom_dev.c
index fcec134..a32aaa1 100644
--- a/sys/geom/geom_dev.c
+++ b/sys/geom/geom_dev.c
@@ -359,7 +359,7 @@ g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread
 	case DIOCSKERNELDUMP:
 		u = *((u_int *)data);
 		if (!u) {
-			set_dumper(NULL);
+			set_dumper(NULL, NULL);
 			error = 0;
 			break;
 		}
@@ -368,7 +368,7 @@ g_dev_ioctl(struct cdev *dev, u_long cmd, caddr_t data, int fflag, struct thread
 		i = sizeof kd;
 		error = g_io_getattr("GEOM::kerneldump", cp, &i, &kd);
 		if (!error) {
-			error = set_dumper(&kd.di);
+			error = set_dumper(&kd.di, devtoname(dev));
 			if (!error)
 				dev->si_flags |= SI_DUMPDEV;
 		}
@@ -526,7 +526,7 @@ g_dev_orphan(struct g_consumer *cp)
 
 	/* Reset any dump-area set on this device */
 	if (dev->si_flags & SI_DUMPDEV)
-		set_dumper(NULL);
+		set_dumper(NULL, NULL);
 
 	/* Destroy the struct cdev *so we get no more requests */
 	destroy_dev(dev);
diff --git a/sys/kern/kern_shutdown.c b/sys/kern/kern_shutdown.c
index d676136..d6c8b2d 100644
--- a/sys/kern/kern_shutdown.c
+++ b/sys/kern/kern_shutdown.c
@@ -712,18 +712,28 @@ kthread_shutdown(void *arg, int howto)
 		printf("done\n");
 }
 
+static char dumpdevname[sizeof(((struct cdev*)NULL)->si_name)];
+SYSCTL_STRING(_kern_shutdown, OID_AUTO, dumpdevname, CTLFLAG_RD,
+    dumpdevname, 0, "Device for kernel dumps");
+
 /* Registration of dumpers */
 int
-set_dumper(struct dumperinfo *di)
+set_dumper(struct dumperinfo *di, const char *devname)
 {
 
 	if (di == NULL) {
 		bzero(&dumper, sizeof dumper);
+		dumpdevname[0] = '\0';
 		return (0);
 	}
 	if (dumper.dumper != NULL)
 		return (EBUSY);
 	dumper = *di;
+	strlcpy(dumpdevname, devname, sizeof(dumpdevname));
+	if (strlen(dumpdevname) != strlen(devname)) {
+		printf("set_dumper: device name truncated from '%s' -> '%s'\n",
+			devname, dumpdevname);
+	}
 	return (0);
 }
 
diff --git a/sys/sys/conf.h b/sys/sys/conf.h
index 96d835b..e818722 100644
--- a/sys/sys/conf.h
+++ b/sys/sys/conf.h
@@ -331,7 +331,7 @@ struct dumperinfo {
 	off_t   mediasize;	/* Space available in bytes. */
 };
 
-int set_dumper(struct dumperinfo *);
+int set_dumper(struct dumperinfo *, const char *_devname);
 int dump_write(struct dumperinfo *, void *, vm_offset_t, off_t, size_t);
 void dumpsys(struct dumperinfo *);
 int doadump(boolean_t);