ide: add warm-plug support for IDE devices (take 2)

* Add 'struct class ide_port_class' ('ide_port' class) and a 'struct device *portdev' ('ide_port' class device) in ide_hwif_t. * Register 'ide_port' class in ide_init() and unregister it in cleanup_module(). * Create ->portdev in ide_register_port () and unregister it in ide_unregister(). * Add "delete_devices" class device attribute for unregistering IDE devices on a port and "scan" one for probing+registering IDE devices on a port. * Add ide_sysfs_register_port() helper for registering "delete_devices" and "scan" attributes with ->portdev. Call it in ide_device_add_all(). * Document IDE warm-plug support in Documentation/ide/warm-plug-howto.txt. v2: * Convert patch from using 'struct class_device' to use 'struct device'. (thanks to Kay Sievers for doing it) Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

ide: add warm-plug support for IDE devices (take 2)
* Add 'struct class ide_port_class' ('ide_port' class) and a 'struct device *portdev' ('ide_port' class device) in ide_hwif_t. * Register 'ide_port' class in ide_init() and unregister it in cleanup_module(). * Create ->portdev in ide_register_port () and unregister it in ide_unregister(). * Add "delete_devices" class device attribute for unregistering IDE devices on a port and "scan" one for probing+registering IDE devices on a port. * Add ide_sysfs_register_port() helper for registering "delete_devices" and "scan" attributes with ->portdev. Call it in ide_device_add_all(). * Document IDE warm-plug support in Documentation/ide/warm-plug-howto.txt. v2: * Convert patch from using 'struct class_device' to use 'struct device'. (thanks to Kay Sievers for doing it) Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Bartlomiej Zolnierkiewicz
1 parent 50672e5d74
Showing 4 changed files with 110 additions and 3 deletions Side-by-side Diff
Documentation/ide/warm-plug-howto.txt
drivers/ide/ide-probe.c
drivers/ide/ide.c
include/linux/ide.h
+
+IDE warm-plug HOWTO
+===================
+
+To warm-plug devices on a port 'idex':
+
+# echo -n "1" > /sys/class/ide_port/idex/delete_devices
+
+unplug old device(s) and plug new device(s)
+
+# echo -n "1" > /sys/class/ide_port/idex/scan
+
+done
@@ -623,7 +623,7 @@
 	complete(&hwif->gendev_rel_comp);
 }
  
-static void ide_register_port(ide_hwif_t *hwif)
+static int ide_register_port(ide_hwif_t *hwif)
 {
 	int ret;
  
  
@@ -639,9 +639,23 @@
 	}
 	hwif->gendev.release = hwif_release_dev;
 	ret = device_register(&hwif->gendev);
-	if (ret < 0)
+	if (ret < 0) {
 		printk(KERN_WARNING "IDE: %s: device_register error: %d\n",
 			__FUNCTION__, ret);
+		goto out;
+	}
+
+	get_device(&hwif->gendev);
+
+	hwif->portdev = device_create(ide_port_class, &hwif->gendev,
+				      MKDEV(0, 0), hwif->name);
+	if (IS_ERR(hwif->portdev)) {
+		ret = PTR_ERR(hwif->portdev);
+		device_unregister(&hwif->gendev);
+	}
+	dev_set_drvdata(hwif->portdev, hwif);
+out:
+	return ret;
 }
  
 /**
@@ -1378,6 +1392,58 @@
 	}
 }
  
+static ssize_t store_delete_devices(struct device *portdev,
+				    struct device_attribute *attr,
+				    const char *buf, size_t n)
+{
+	ide_hwif_t *hwif = dev_get_drvdata(portdev);
+
+	if (strncmp(buf, "1", n))
+		return -EINVAL;
+
+	ide_port_unregister_devices(hwif);
+
+	return n;
+};
+
+static DEVICE_ATTR(delete_devices, S_IWUSR, NULL, store_delete_devices);
+
+static ssize_t store_scan(struct device *portdev,
+			  struct device_attribute *attr,
+			  const char *buf, size_t n)
+{
+	ide_hwif_t *hwif = dev_get_drvdata(portdev);
+
+	if (strncmp(buf, "1", n))
+		return -EINVAL;
+
+	ide_port_unregister_devices(hwif);
+	ide_port_scan(hwif);
+
+	return n;
+};
+
+static DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
+
+static struct device_attribute *ide_port_attrs[] = {
+	&dev_attr_delete_devices,
+	&dev_attr_scan,
+	NULL
+};
+
+static int ide_sysfs_register_port(ide_hwif_t *hwif)
+{
+	int i, rc;
+
+	for (i = 0; ide_port_attrs[i]; i++) {
+		rc = device_create_file(hwif->portdev, ide_port_attrs[i]);
+		if (rc)
+			break;
+	}
+
+	return rc;
+}
+
 int ide_device_add_all(u8 *idx, const struct ide_port_info *d)
 {
 	ide_hwif_t *hwif, *mate = NULL;
@@ -1474,6 +1540,7 @@
 		hwif = &ide_hwifs[idx[i]];
  
 		if (hwif->present) {
+			ide_sysfs_register_port(hwif);
 			ide_proc_register_port(hwif);
 			ide_proc_port_register_devices(hwif);
 		}
@@ -78,6 +78,8 @@
 /* default maximum number of failures */
 #define IDE_DEFAULT_MAX_FAILURES 	1
  
+struct class *ide_port_class;
+
 static const u8 ide_hwif_to_major[] = { IDE0_MAJOR, IDE1_MAJOR,
 					IDE2_MAJOR, IDE3_MAJOR,
 					IDE4_MAJOR, IDE5_MAJOR,
@@ -591,6 +593,7 @@
  
 	ide_remove_port_from_hwgroup(hwif);
  
+	device_unregister(hwif->portdev);
 	device_unregister(&hwif->gendev);
 	wait_for_completion(&hwif->gendev_rel_comp);
  
@@ -1590,6 +1593,13 @@
  
 EXPORT_SYMBOL_GPL(ide_bus_type);
  
+static void ide_port_class_release(struct device *portdev)
+{
+	ide_hwif_t *hwif = dev_get_drvdata(portdev);
+
+	put_device(&hwif->gendev);
+}
+
 /*
  * This is gets invoked once during initialization, to set *everything* up
  */
  
@@ -1610,11 +1620,23 @@
 		return ret;
 	}
  
+	ide_port_class = class_create(THIS_MODULE, "ide_port");
+	if (IS_ERR(ide_port_class)) {
+		ret = PTR_ERR(ide_port_class);
+		goto out_port_class;
+	}
+	ide_port_class->dev_release = ide_port_class_release;
+
 	init_ide_data();
  
 	proc_ide_create();
  
 	return 0;
+
+out_port_class:
+	bus_unregister(&ide_bus_type);
+
+	return ret;
 }
  
 #ifdef MODULE
@@ -1650,6 +1672,8 @@
 		ide_unregister(index, 0, 0);
  
 	proc_ide_destroy();
+
+	class_destroy(ide_port_class);
  
 	bus_unregister(&ide_bus_type);
 }
@@ -579,7 +579,9 @@
 	unsigned	mmio       : 1; /* host uses MMIO */
 	unsigned	straight8  : 1;	/* Alan's straight 8 check */
  
-	struct device	gendev;
+	struct device		gendev;
+	struct device		*portdev;
+
 	struct completion gendev_rel_comp; /* To deal with device release() */
  
 	void		*hwif_data;	/* extra hwif data */
@@ -1275,6 +1277,7 @@
 #define local_irq_set(flags)	do { local_save_flags((flags)); local_irq_enable_in_hardirq(); } while (0)
  
 extern struct bus_type ide_bus_type;
+extern struct class *ide_port_class;
  
 /* check if CACHE FLUSH (EXT) command is supported (bits defined in ATA-6) */
 #define ide_id_has_flush_cache(id)	((id)->cfs_enable_2 & 0x3000)
	1	+
	2	+IDE warm-plug HOWTO
	3	+===================
	4	+
	5	+To warm-plug devices on a port 'idex':
	6	+
	7	+# echo -n "1" > /sys/class/ide_port/idex/delete_devices
	8	+
	9	+unplug old device(s) and plug new device(s)
	10	+
	11	+# echo -n "1" > /sys/class/ide_port/idex/scan
	12	+
	13	+done
...	...	@@ -623,7 +623,7 @@
623	623	complete(&hwif->gendev_rel_comp);
624	624	}
625	625
626		-static void ide_register_port(ide_hwif_t *hwif)
	626	+static int ide_register_port(ide_hwif_t *hwif)
627	627	{
628	628	int ret;
629	629
630	630
...	...	@@ -639,9 +639,23 @@
639	639	}
640	640	hwif->gendev.release = hwif_release_dev;
641	641	ret = device_register(&hwif->gendev);
642		- if (ret < 0)
	642	+ if (ret < 0) {
643	643	printk(KERN_WARNING "IDE: %s: device_register error: %d\n",
644	644	__FUNCTION__, ret);
	645	+ goto out;
	646	+ }
	647	+
	648	+ get_device(&hwif->gendev);
	649	+
	650	+ hwif->portdev = device_create(ide_port_class, &hwif->gendev,
	651	+ MKDEV(0, 0), hwif->name);
	652	+ if (IS_ERR(hwif->portdev)) {
	653	+ ret = PTR_ERR(hwif->portdev);
	654	+ device_unregister(&hwif->gendev);
	655	+ }
	656	+ dev_set_drvdata(hwif->portdev, hwif);
	657	+out:
	658	+ return ret;
645	659	}
646	660
647	661	/**
...	...	@@ -1378,6 +1392,58 @@
1378	1392	}
1379	1393	}
1380	1394
	1395	+static ssize_t store_delete_devices(struct device *portdev,
	1396	+ struct device_attribute *attr,
	1397	+ const char *buf, size_t n)
	1398	+{
	1399	+ ide_hwif_t *hwif = dev_get_drvdata(portdev);
	1400	+
	1401	+ if (strncmp(buf, "1", n))
	1402	+ return -EINVAL;
	1403	+
	1404	+ ide_port_unregister_devices(hwif);
	1405	+
	1406	+ return n;
	1407	+};
	1408	+
	1409	+static DEVICE_ATTR(delete_devices, S_IWUSR, NULL, store_delete_devices);
	1410	+
	1411	+static ssize_t store_scan(struct device *portdev,
	1412	+ struct device_attribute *attr,
	1413	+ const char *buf, size_t n)
	1414	+{
	1415	+ ide_hwif_t *hwif = dev_get_drvdata(portdev);
	1416	+
	1417	+ if (strncmp(buf, "1", n))
	1418	+ return -EINVAL;
	1419	+
	1420	+ ide_port_unregister_devices(hwif);
	1421	+ ide_port_scan(hwif);
	1422	+
	1423	+ return n;
	1424	+};
	1425	+
	1426	+static DEVICE_ATTR(scan, S_IWUSR, NULL, store_scan);
	1427	+
	1428	+static struct device_attribute *ide_port_attrs[] = {
	1429	+ &dev_attr_delete_devices,
	1430	+ &dev_attr_scan,
	1431	+ NULL
	1432	+};
	1433	+
	1434	+static int ide_sysfs_register_port(ide_hwif_t *hwif)
	1435	+{
	1436	+ int i, rc;
	1437	+
	1438	+ for (i = 0; ide_port_attrs[i]; i++) {
	1439	+ rc = device_create_file(hwif->portdev, ide_port_attrs[i]);
	1440	+ if (rc)
	1441	+ break;
	1442	+ }
	1443	+
	1444	+ return rc;
	1445	+}
	1446	+
1381	1447	int ide_device_add_all(u8 idx, const struct ide_port_info d)
1382	1448	{
1383	1449	ide_hwif_t hwif, mate = NULL;
...	...	@@ -1474,6 +1540,7 @@
1474	1540	hwif = &ide_hwifs[idx[i]];
1475	1541
1476	1542	if (hwif->present) {
	1543	+ ide_sysfs_register_port(hwif);
1477	1544	ide_proc_register_port(hwif);
1478	1545	ide_proc_port_register_devices(hwif);
1479	1546	}
...	...	@@ -78,6 +78,8 @@
78	78	/* default maximum number of failures */
79	79	#define IDE_DEFAULT_MAX_FAILURES 1
80	80
	81	+struct class *ide_port_class;
	82	+
81	83	static const u8 ide_hwif_to_major[] = { IDE0_MAJOR, IDE1_MAJOR,
82	84	IDE2_MAJOR, IDE3_MAJOR,
83	85	IDE4_MAJOR, IDE5_MAJOR,
...	...	@@ -591,6 +593,7 @@
591	593
592	594	ide_remove_port_from_hwgroup(hwif);
593	595
	596	+ device_unregister(hwif->portdev);
594	597	device_unregister(&hwif->gendev);
595	598	wait_for_completion(&hwif->gendev_rel_comp);
596	599
...	...	@@ -1590,6 +1593,13 @@
1590	1593
1591	1594	EXPORT_SYMBOL_GPL(ide_bus_type);
1592	1595
	1596	+static void ide_port_class_release(struct device *portdev)
	1597	+{
	1598	+ ide_hwif_t *hwif = dev_get_drvdata(portdev);
	1599	+
	1600	+ put_device(&hwif->gendev);
	1601	+}
	1602	+
1593	1603	/*
1594	1604	* This is gets invoked once during initialization, to set everything up
1595	1605	*/
1596	1606
...	...	@@ -1610,11 +1620,23 @@
1610	1620	return ret;
1611	1621	}
1612	1622
	1623	+ ide_port_class = class_create(THIS_MODULE, "ide_port");
	1624	+ if (IS_ERR(ide_port_class)) {
	1625	+ ret = PTR_ERR(ide_port_class);
	1626	+ goto out_port_class;
	1627	+ }
	1628	+ ide_port_class->dev_release = ide_port_class_release;
	1629	+
1613	1630	init_ide_data();
1614	1631
1615	1632	proc_ide_create();
1616	1633
1617	1634	return 0;
	1635	+
	1636	+out_port_class:
	1637	+ bus_unregister(&ide_bus_type);
	1638	+
	1639	+ return ret;
1618	1640	}
1619	1641
1620	1642	#ifdef MODULE
...	...	@@ -1650,6 +1672,8 @@
1650	1672	ide_unregister(index, 0, 0);
1651	1673
1652	1674	proc_ide_destroy();
	1675	+
	1676	+ class_destroy(ide_port_class);
1653	1677
1654	1678	bus_unregister(&ide_bus_type);
1655	1679	}
...	...	@@ -579,7 +579,9 @@
579	579	unsigned mmio : 1; /* host uses MMIO */
580	580	unsigned straight8 : 1; /* Alan's straight 8 check */
581	581
582		- struct device gendev;
	582	+ struct device gendev;
	583	+ struct device *portdev;
	584	+
583	585	struct completion gendev_rel_comp; /* To deal with device release() */
584	586
585	587	void hwif_data; / extra hwif data */
...	...	@@ -1275,6 +1277,7 @@
1275	1277	#define local_irq_set(flags) do { local_save_flags((flags)); local_irq_enable_in_hardirq(); } while (0)
1276	1278
1277	1279	extern struct bus_type ide_bus_type;
	1280	+extern struct class *ide_port_class;
1278	1281
1279	1282	/* check if CACHE FLUSH (EXT) command is supported (bits defined in ATA-6) */
1280	1283	#define ide_id_has_flush_cache(id) ((id)->cfs_enable_2 & 0x3000)