Add a "spindown" facility to ata-disks: If no requests have been received

for a configurable number of seconds, spin the disk down.  Spin it back
up on the next request.

Notice that the timeout is only armed by a request, so to spin down a
disk you may have to do:

	atacontrol spindown ad10 5
	dd if=/dev/ad10 of=/dev/null count=1

To disable spindown, set timeout to zero:

	atacontrol spindown ad10 0

In order to debug any trouble caused, this code is somewhat noisy on the
console.

Enabling spindown on a disk containing / or /var/log/messages is not
going to do anything sensible.

Spinning a disk up and down all the time will wear it out, use sensibly.

Approved by:	sos

2 files changed, 35 insertions, 0 deletions

diff --git a/sbin/atacontrol/atacontrol.8 b/sbin/atacontrol/atacontrol.8
index dd25f57..a755483 100644
--- a/sbin/atacontrol/atacontrol.8
+++ b/sbin/atacontrol/atacontrol.8
@@ -70,6 +70,10 @@
 .Ic cap
 .Ar device
 .Nm
+.Ic spindown
+.Ar device
+.Op Ar seconds
+.Nm
 .Ic list
 .Sh DESCRIPTION
 The
@@ -190,6 +194,10 @@ The device name and manufacture/version strings are shown.
 .It Ic cap
 Show detailed info about the device on
 .Ar device .
+.It Ic spindown
+Set or report timeout after which the
+.Ar device 
+will be spun down.
 .It Ic info
 Show info about the attached devices on the
 .Ar channel .
diff --git a/sbin/atacontrol/atacontrol.c b/sbin/atacontrol/atacontrol.c
index 42ee65f..590b29c 100644
--- a/sbin/atacontrol/atacontrol.c
+++ b/sbin/atacontrol/atacontrol.c
@@ -102,6 +102,7 @@ usage(void)
 		"        atacontrol status array\n"
 		"        atacontrol mode device [mode]\n"
 		"        atacontrol cap device\n"
+		"        atacontrol spindown device [seconds]\n"
 	);
 	exit(EX_USAGE);
 }
@@ -285,6 +286,26 @@ info_print(int fd, int channel, int prchan)
 		printf("     no device present\n");
 }
 
+static void
+ata_spindown(int fd, const char *dev, const char *arg)
+{
+	int tmo;
+
+	if (arg != NULL) {
+		tmo = strtoul(arg, NULL, 0);
+		if (ioctl(fd, IOCATASSPINDOWN, &tmo) < 0)
+			err(1, "ioctl(IOCATASSPINDOWN)");
+	} else {
+		if (ioctl(fd, IOCATAGSPINDOWN, &tmo) < 0)
+			err(1, "ioctl(IOCATAGSPINDOWN)");
+		if (tmo == 0)
+			printf("%s: idle spin down disabled\n", dev);
+		else
+			printf("%s: spin down after %d seconds idle\n",
+			    dev, tmo);
+	}
+}
+
 static int
 open_dev(const char *arg, int mode)
 {
@@ -356,6 +377,12 @@ main(int argc, char **argv)
 		exit(EX_OK);
 	}
 
+	if (!strcmp(argv[1], "spindown") && (argc == 3 || argc == 4)) {
+		fd = open_dev(argv[2], O_RDONLY);
+		ata_spindown(fd, argv[2], argv[3]);
+		exit(EX_OK);
+	}
+
 	if ((fd = open("/dev/ata", O_RDWR)) < 0)
 		err(1, "control device not found");