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

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 .

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");
 

sys/dev/ata/ata-all.c

@@ -514,6 +514,12 @@ ata_device_ioctl(device_t dev, u_long cmd, caddr_t data)
     case IOCATAGMODE:
 	*mode = atadev->mode;
 	return 0;
+    case IOCATASSPINDOWN:
+	atadev->spindown = *mode;
+	return 0;
+    case IOCATAGSPINDOWN:
+	*mode = atadev->spindown;
+	return 0;
     default:
 	return ENOTTY;
     }

sys/dev/ata/ata-all.h

@@ -403,6 +403,9 @@ struct ata_device {
     struct ata_params           param;          /* ata param structure */
     int                         mode;           /* current transfermode */
     u_int32_t                   max_iosize;     /* max IO size */
+    int				spindown;	/* idle spindown timeout */
+    struct callout              spindown_timer;
+    int                         spindown_state;
     int                         flags;
 #define         ATA_D_USE_CHS           0x0001
 #define         ATA_D_MEDIA_CHANGED     0x0002

sys/dev/ata/ata-disk.c

@@ -171,6 +171,8 @@ ad_attach(device_t dev)
     device_add_child(dev, "subdisk", device_get_unit(dev));
     ad_firmware_geom_adjust(dev, adp->disk);
     bus_generic_attach(dev);
+
+    callout_init(&atadev->spindown_timer, 1);
     return 0;
 }
 
@@ -178,6 +180,7 @@ static int
 ad_detach(device_t dev)
 {
     struct ad_softc *adp = device_get_ivars(dev);
+    struct ata_device *atadev = device_get_softc(dev);
     device_t *children;
     int nchildren, i;
 
@@ -185,6 +188,9 @@ ad_detach(device_t dev)
     if (!device_get_ivars(dev))
 	return ENXIO;
     
+    /* destroy the power timeout */
+    callout_drain(&atadev->spindown_timer);
+
     /* detach & delete all children */
     if (!device_get_children(dev, &children, &nchildren)) {
 	for (i = 0; i < nchildren; i++)
@@ -229,6 +235,38 @@ ad_reinit(device_t dev)
     return 0;
 }
 
+static void
+ad_power_callback(struct ata_request *request)
+{
+    device_printf(request->dev, "drive spun down.\n");
+    ata_free_request(request);
+}
+
+static void
+ad_spindown(void *priv)
+{
+    device_t dev = priv;
+    struct ata_device *atadev = device_get_softc(dev);
+    struct ata_request *request;
+
+    if(atadev->spindown == 0)
+	return;
+    device_printf(dev, "Idle, spin down\n");
+    atadev->spindown_state = 1;
+    if (!(request = ata_alloc_request())) {
+	device_printf(dev, "FAILURE - out of memory in ad_spindown\n");
+	return;
+    }
+    request->flags = ATA_R_CONTROL;
+    request->dev = dev;
+    request->timeout = 5;
+    request->retries = 1;
+    request->callback = ad_power_callback;
+    request->u.ata.command = ATA_STANDBY_IMMEDIATE;
+    ata_queue_request(request);
+}
+
+
 static void 
 ad_strategy(struct bio *bp)
 {
@@ -236,6 +274,10 @@ ad_strategy(struct bio *bp)
     struct ata_device *atadev = device_get_softc(dev);
     struct ata_request *request;
 
+    if (atadev->spindown != 0)
+	callout_reset(&atadev->spindown_timer, hz * atadev->spindown,
+	    ad_spindown, dev);
+
     if (!(request = ata_alloc_request())) {
 	device_printf(dev, "FAILURE - out of memory in start\n");
 	biofinish(bp, NULL, ENOMEM);
@@ -246,7 +288,13 @@ ad_strategy(struct bio *bp)
     request->dev = dev;
     request->bio = bp;
     request->callback = ad_done;
-    request->timeout = 5;
+    if (atadev->spindown_state) {
+	device_printf(dev, "request while spun down, starting.\n");
+	atadev->spindown_state = 0;
+	request->timeout = 31;
+    } else {
+	request->timeout = 5;
+    }
     request->retries = 2;
     request->data = bp->bio_data;
     request->bytecount = bp->bio_bcount;

sys/dev/ata/ata-disk.h

@@ -34,7 +34,7 @@ struct ad_softc {
     u_int32_t                   transfersize;   /* size of each transfer */
     int                         num_tags;       /* number of tags supported */
     int                         flags;          /* drive flags */
-#define         AD_F_LABELLING          0x0001          
+#define         AD_F_LABELLING          0x0001
 #define         AD_F_CHS_USED           0x0002
 #define         AD_F_32B_ENABLED        0x0004
 #define         AD_F_TAG_ENABLED        0x0008

sys/sys/ata.h

@@ -433,6 +433,9 @@ struct ata_ioc_request {
 #define IOCATAGMODE             _IOR('a', 102, int)
 #define IOCATASMODE             _IOW('a', 103, int)
 
+#define IOCATAGSPINDOWN		_IOR('a', 104, int)
+#define IOCATASSPINDOWN		_IOW('a', 105, int)
+
 
 struct ata_ioc_raid_config {
 	    int                 lun;