Merge tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio

Pull vfio update from Alex Williamson: - convert to misc driver to support module auto loading - remove unnecessary and dangerous use of device_lock * tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio: vfio-pci: Don't use device_lock around AER interrupt setup vfio: Convert control interface to misc driver misc: Reserve minor for VFIO

Merge tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio
Pull vfio update from Alex Williamson: - convert to misc driver to support module auto loading - remove unnecessary and dangerous use of device_lock * tag 'vfio-v3.14-rc1' of git://github.com/awilliam/linux-vfio: vfio-pci: Don't use device_lock around AER interrupt setup vfio: Convert control interface to misc driver misc: Reserve minor for VFIO
Linus Torvalds
2 parents 5c85121bf6 3be3a074cf
Showing 5 changed files Side-by-side Diff
Documentation/devices.txt
drivers/vfio/pci/vfio_pci.c
drivers/vfio/pci/vfio_pci_intrs.c
drivers/vfio/vfio.c
include/linux/miscdevice.h
@@ -409,6 +409,7 @@
 		193 = /dev/d7s		SPARC 7-segment display
 		194 = /dev/zkshim	Zero-Knowledge network shim control
 		195 = /dev/elographics/e2201	Elographics touchscreen E271-2201
+		196 = /dev/vfio/vfio	VFIO userspace driver interface
 		198 = /dev/sexec	Signed executable interface
 		199 = /dev/scanners/cuecat :CueCat barcode scanner
 		200 = /dev/net/tun	TAP/TUN network device
@@ -872,8 +872,12 @@
 		return PCI_ERS_RESULT_DISCONNECT;
 	}
  
+	mutex_lock(&vdev->igate);
+
 	if (vdev->err_trigger)
 		eventfd_signal(vdev->err_trigger, 1);
+
+	mutex_unlock(&vdev->igate);
  
 	vfio_device_put(device);
  
@@ -749,54 +749,37 @@
 				    unsigned count, uint32_t flags, void *data)
 {
 	int32_t fd = *(int32_t *)data;
-	struct pci_dev *pdev = vdev->pdev;
  
 	if ((index != VFIO_PCI_ERR_IRQ_INDEX) ||
 	    !(flags & VFIO_IRQ_SET_DATA_TYPE_MASK))
 		return -EINVAL;
  
-	/*
-	 * device_lock synchronizes setting and checking of
-	 * err_trigger. The vfio_pci_aer_err_detected() is also
-	 * called with device_lock held.
-	 */
-
 	/* DATA_NONE/DATA_BOOL enables loopback testing */
-
 	if (flags & VFIO_IRQ_SET_DATA_NONE) {
-		device_lock(&pdev->dev);
 		if (vdev->err_trigger)
 			eventfd_signal(vdev->err_trigger, 1);
-		device_unlock(&pdev->dev);
 		return 0;
 	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
 		uint8_t trigger = *(uint8_t *)data;
-		device_lock(&pdev->dev);
 		if (trigger && vdev->err_trigger)
 			eventfd_signal(vdev->err_trigger, 1);
-		device_unlock(&pdev->dev);
 		return 0;
 	}
  
 	/* Handle SET_DATA_EVENTFD */
-
 	if (fd == -1) {
-		device_lock(&pdev->dev);
 		if (vdev->err_trigger)
 			eventfd_ctx_put(vdev->err_trigger);
 		vdev->err_trigger = NULL;
-		device_unlock(&pdev->dev);
 		return 0;
 	} else if (fd >= 0) {
 		struct eventfd_ctx *efdctx;
 		efdctx = eventfd_ctx_fdget(fd);
 		if (IS_ERR(efdctx))
 			return PTR_ERR(efdctx);
-		device_lock(&pdev->dev);
 		if (vdev->err_trigger)
 			eventfd_ctx_put(vdev->err_trigger);
 		vdev->err_trigger = efdctx;
-		device_unlock(&pdev->dev);
 		return 0;
 	} else
 		return -EINVAL;
@@ -22,6 +22,7 @@
 #include <linux/idr.h>
 #include <linux/iommu.h>
 #include <linux/list.h>
+#include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/mutex.h>
 #include <linux/rwsem.h>
@@ -45,9 +46,7 @@
 	struct idr			group_idr;
 	struct mutex			group_lock;
 	struct cdev			group_cdev;
-	struct device			*dev;
-	dev_t				devt;
-	struct cdev			cdev;
+	dev_t				group_devt;
 	wait_queue_head_t		release_q;
 } vfio;
  
@@ -142,8 +141,7 @@
  */
 static int vfio_alloc_group_minor(struct vfio_group *group)
 {
-	/* index 0 is used by /dev/vfio/vfio */
-	return idr_alloc(&vfio.group_idr, group, 1, MINORMASK + 1, GFP_KERNEL);
+	return idr_alloc(&vfio.group_idr, group, 0, MINORMASK + 1, GFP_KERNEL);
 }
  
 static void vfio_free_group_minor(int minor)
@@ -243,7 +241,8 @@
 		}
 	}
  
-	dev = device_create(vfio.class, NULL, MKDEV(MAJOR(vfio.devt), minor),
+	dev = device_create(vfio.class, NULL,
+			    MKDEV(MAJOR(vfio.group_devt), minor),
 			    group, "%d", iommu_group_id(iommu_group));
 	if (IS_ERR(dev)) {
 		vfio_free_group_minor(minor);
@@ -268,7 +267,7 @@
  
 	WARN_ON(!list_empty(&group->device_list));
  
-	device_destroy(vfio.class, MKDEV(MAJOR(vfio.devt), group->minor));
+	device_destroy(vfio.class, MKDEV(MAJOR(vfio.group_devt), group->minor));
 	list_del(&group->vfio_next);
 	vfio_free_group_minor(group->minor);
 	vfio_group_unlock_and_free(group);
  
@@ -1419,12 +1418,17 @@
  */
 static char *vfio_devnode(struct device *dev, umode_t *mode)
 {
-	if (mode && (MINOR(dev->devt) == 0))
-		*mode = S_IRUGO | S_IWUGO;
-
 	return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));
 }
  
+static struct miscdevice vfio_dev = {
+	.minor = VFIO_MINOR,
+	.name = "vfio",
+	.fops = &vfio_fops,
+	.nodename = "vfio/vfio",
+	.mode = S_IRUGO | S_IWUGO,
+};
+
 static int __init vfio_init(void)
 {
 	int ret;
@@ -1436,6 +1440,13 @@
 	INIT_LIST_HEAD(&vfio.iommu_drivers_list);
 	init_waitqueue_head(&vfio.release_q);
  
+	ret = misc_register(&vfio_dev);
+	if (ret) {
+		pr_err("vfio: misc device register failed\n");
+		return ret;
+	}
+
+	/* /dev/vfio/$GROUP */
 	vfio.class = class_create(THIS_MODULE, "vfio");
 	if (IS_ERR(vfio.class)) {
 		ret = PTR_ERR(vfio.class);
  
  
  
  
@@ -1444,27 +1455,14 @@
  
 	vfio.class->devnode = vfio_devnode;
  
-	ret = alloc_chrdev_region(&vfio.devt, 0, MINORMASK, "vfio");
+	ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK, "vfio");
 	if (ret)
-		goto err_base_chrdev;
+		goto err_alloc_chrdev;
  
-	cdev_init(&vfio.cdev, &vfio_fops);
-	ret = cdev_add(&vfio.cdev, vfio.devt, 1);
-	if (ret)
-		goto err_base_cdev;
-
-	vfio.dev = device_create(vfio.class, NULL, vfio.devt, NULL, "vfio");
-	if (IS_ERR(vfio.dev)) {
-		ret = PTR_ERR(vfio.dev);
-		goto err_base_dev;
-	}
-
-	/* /dev/vfio/$GROUP */
 	cdev_init(&vfio.group_cdev, &vfio_group_fops);
-	ret = cdev_add(&vfio.group_cdev,
-		       MKDEV(MAJOR(vfio.devt), 1), MINORMASK - 1);
+	ret = cdev_add(&vfio.group_cdev, vfio.group_devt, MINORMASK);
 	if (ret)
-		goto err_groups_cdev;
+		goto err_cdev_add;
  
 	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
  
  
@@ -1478,16 +1476,13 @@
  
 	return 0;
  
-err_groups_cdev:
-	device_destroy(vfio.class, vfio.devt);
-err_base_dev:
-	cdev_del(&vfio.cdev);
-err_base_cdev:
-	unregister_chrdev_region(vfio.devt, MINORMASK);
-err_base_chrdev:
+err_cdev_add:
+	unregister_chrdev_region(vfio.group_devt, MINORMASK);
+err_alloc_chrdev:
 	class_destroy(vfio.class);
 	vfio.class = NULL;
 err_class:
+	misc_deregister(&vfio_dev);
 	return ret;
 }
  
  
@@ -1497,11 +1492,10 @@
  
 	idr_destroy(&vfio.group_idr);
 	cdev_del(&vfio.group_cdev);
-	device_destroy(vfio.class, vfio.devt);
-	cdev_del(&vfio.cdev);
-	unregister_chrdev_region(vfio.devt, MINORMASK);
+	unregister_chrdev_region(vfio.group_devt, MINORMASK);
 	class_destroy(vfio.class);
 	vfio.class = NULL;
+	misc_deregister(&vfio_dev);
 }
  
 module_init(vfio_init);
@@ -1511,4 +1505,6 @@
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_ALIAS_MISCDEV(VFIO_MINOR);
+MODULE_ALIAS("devname:vfio/vfio");
@@ -30,6 +30,7 @@
 #define STORE_QUEUE_MINOR	155
 #define I2O_MINOR		166
 #define MICROCODE_MINOR		184
+#define VFIO_MINOR		196
 #define TUN_MINOR		200
 #define CUSE_MINOR		203
 #define MWAVE_MINOR		219	/* ACP/Mwave Modem */
...	...	@@ -409,6 +409,7 @@
409	409	193 = /dev/d7s SPARC 7-segment display
410	410	194 = /dev/zkshim Zero-Knowledge network shim control
411	411	195 = /dev/elographics/e2201 Elographics touchscreen E271-2201
	412	+ 196 = /dev/vfio/vfio VFIO userspace driver interface
412	413	198 = /dev/sexec Signed executable interface
413	414	199 = /dev/scanners/cuecat :CueCat barcode scanner
414	415	200 = /dev/net/tun TAP/TUN network device
...	...	@@ -872,8 +872,12 @@
872	872	return PCI_ERS_RESULT_DISCONNECT;
873	873	}
874	874
	875	+ mutex_lock(&vdev->igate);
	876	+
875	877	if (vdev->err_trigger)
876	878	eventfd_signal(vdev->err_trigger, 1);
	879	+
	880	+ mutex_unlock(&vdev->igate);
877	881
878	882	vfio_device_put(device);
879	883
...	...	@@ -749,54 +749,37 @@
749	749	unsigned count, uint32_t flags, void *data)
750	750	{
751	751	int32_t fd = (int32_t )data;
752		- struct pci_dev *pdev = vdev->pdev;
753	752
754	753	if ((index != VFIO_PCI_ERR_IRQ_INDEX) \|\|
755	754	!(flags & VFIO_IRQ_SET_DATA_TYPE_MASK))
756	755	return -EINVAL;
757	756
758		- /*
759		- * device_lock synchronizes setting and checking of
760		- * err_trigger. The vfio_pci_aer_err_detected() is also
761		- * called with device_lock held.
762		- */
763		-
764	757	/* DATA_NONE/DATA_BOOL enables loopback testing */
765		-
766	758	if (flags & VFIO_IRQ_SET_DATA_NONE) {
767		- device_lock(&pdev->dev);
768	759	if (vdev->err_trigger)
769	760	eventfd_signal(vdev->err_trigger, 1);
770		- device_unlock(&pdev->dev);
771	761	return 0;
772	762	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
773	763	uint8_t trigger = (uint8_t )data;
774		- device_lock(&pdev->dev);
775	764	if (trigger && vdev->err_trigger)
776	765	eventfd_signal(vdev->err_trigger, 1);
777		- device_unlock(&pdev->dev);
778	766	return 0;
779	767	}
780	768
781	769	/* Handle SET_DATA_EVENTFD */
782		-
783	770	if (fd == -1) {
784		- device_lock(&pdev->dev);
785	771	if (vdev->err_trigger)
786	772	eventfd_ctx_put(vdev->err_trigger);
787	773	vdev->err_trigger = NULL;
788		- device_unlock(&pdev->dev);
789	774	return 0;
790	775	} else if (fd >= 0) {
791	776	struct eventfd_ctx *efdctx;
792	777	efdctx = eventfd_ctx_fdget(fd);
793	778	if (IS_ERR(efdctx))
794	779	return PTR_ERR(efdctx);
795		- device_lock(&pdev->dev);
796	780	if (vdev->err_trigger)
797	781	eventfd_ctx_put(vdev->err_trigger);
798	782	vdev->err_trigger = efdctx;
799		- device_unlock(&pdev->dev);
800	783	return 0;
801	784	} else
802	785	return -EINVAL;
...	...	@@ -22,6 +22,7 @@
22	22	#include <linux/idr.h>
23	23	#include <linux/iommu.h>
24	24	#include <linux/list.h>
	25	+#include <linux/miscdevice.h>
25	26	#include <linux/module.h>
26	27	#include <linux/mutex.h>
27	28	#include <linux/rwsem.h>
...	...	@@ -45,9 +46,7 @@
45	46	struct idr group_idr;
46	47	struct mutex group_lock;
47	48	struct cdev group_cdev;
48		- struct device *dev;
49		- dev_t devt;
50		- struct cdev cdev;
	49	+ dev_t group_devt;
51	50	wait_queue_head_t release_q;
52	51	} vfio;
53	52
...	...	@@ -142,8 +141,7 @@
142	141	*/
143	142	static int vfio_alloc_group_minor(struct vfio_group *group)
144	143	{
145		- /* index 0 is used by /dev/vfio/vfio */
146		- return idr_alloc(&vfio.group_idr, group, 1, MINORMASK + 1, GFP_KERNEL);
	144	+ return idr_alloc(&vfio.group_idr, group, 0, MINORMASK + 1, GFP_KERNEL);
147	145	}
148	146
149	147	static void vfio_free_group_minor(int minor)
...	...	@@ -243,7 +241,8 @@
243	241	}
244	242	}
245	243
246		- dev = device_create(vfio.class, NULL, MKDEV(MAJOR(vfio.devt), minor),
	244	+ dev = device_create(vfio.class, NULL,
	245	+ MKDEV(MAJOR(vfio.group_devt), minor),
247	246	group, "%d", iommu_group_id(iommu_group));
248	247	if (IS_ERR(dev)) {
249	248	vfio_free_group_minor(minor);
...	...	@@ -268,7 +267,7 @@
268	267
269	268	WARN_ON(!list_empty(&group->device_list));
270	269
271		- device_destroy(vfio.class, MKDEV(MAJOR(vfio.devt), group->minor));
	270	+ device_destroy(vfio.class, MKDEV(MAJOR(vfio.group_devt), group->minor));
272	271	list_del(&group->vfio_next);
273	272	vfio_free_group_minor(group->minor);
274	273	vfio_group_unlock_and_free(group);
275	274
...	...	@@ -1419,12 +1418,17 @@
1419	1418	*/
1420	1419	static char vfio_devnode(struct device dev, umode_t *mode)
1421	1420	{
1422		- if (mode && (MINOR(dev->devt) == 0))
1423		- *mode = S_IRUGO \| S_IWUGO;
1424		-
1425	1421	return kasprintf(GFP_KERNEL, "vfio/%s", dev_name(dev));
1426	1422	}
1427	1423
	1424	+static struct miscdevice vfio_dev = {
	1425	+ .minor = VFIO_MINOR,
	1426	+ .name = "vfio",
	1427	+ .fops = &vfio_fops,
	1428	+ .nodename = "vfio/vfio",
	1429	+ .mode = S_IRUGO \| S_IWUGO,
	1430	+};
	1431	+
1428	1432	static int __init vfio_init(void)
1429	1433	{
1430	1434	int ret;
...	...	@@ -1436,6 +1440,13 @@
1436	1440	INIT_LIST_HEAD(&vfio.iommu_drivers_list);
1437	1441	init_waitqueue_head(&vfio.release_q);
1438	1442
	1443	+ ret = misc_register(&vfio_dev);
	1444	+ if (ret) {
	1445	+ pr_err("vfio: misc device register failed\n");
	1446	+ return ret;
	1447	+ }
	1448	+
	1449	+ /* /dev/vfio/$GROUP */
1439	1450	vfio.class = class_create(THIS_MODULE, "vfio");
1440	1451	if (IS_ERR(vfio.class)) {
1441	1452	ret = PTR_ERR(vfio.class);
1442	1453
1443	1454
1444	1455
1445	1456
...	...	@@ -1444,27 +1455,14 @@
1444	1455
1445	1456	vfio.class->devnode = vfio_devnode;
1446	1457
1447		- ret = alloc_chrdev_region(&vfio.devt, 0, MINORMASK, "vfio");
	1458	+ ret = alloc_chrdev_region(&vfio.group_devt, 0, MINORMASK, "vfio");
1448	1459	if (ret)
1449		- goto err_base_chrdev;
	1460	+ goto err_alloc_chrdev;
1450	1461
1451		- cdev_init(&vfio.cdev, &vfio_fops);
1452		- ret = cdev_add(&vfio.cdev, vfio.devt, 1);
1453		- if (ret)
1454		- goto err_base_cdev;
1455		-
1456		- vfio.dev = device_create(vfio.class, NULL, vfio.devt, NULL, "vfio");
1457		- if (IS_ERR(vfio.dev)) {
1458		- ret = PTR_ERR(vfio.dev);
1459		- goto err_base_dev;
1460		- }
1461		-
1462		- /* /dev/vfio/$GROUP */
1463	1462	cdev_init(&vfio.group_cdev, &vfio_group_fops);
1464		- ret = cdev_add(&vfio.group_cdev,
1465		- MKDEV(MAJOR(vfio.devt), 1), MINORMASK - 1);
	1463	+ ret = cdev_add(&vfio.group_cdev, vfio.group_devt, MINORMASK);
1466	1464	if (ret)
1467		- goto err_groups_cdev;
	1465	+ goto err_cdev_add;
1468	1466
1469	1467	pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
1470	1468
1471	1469
...	...	@@ -1478,16 +1476,13 @@
1478	1476
1479	1477	return 0;
1480	1478
1481		-err_groups_cdev:
1482		- device_destroy(vfio.class, vfio.devt);
1483		-err_base_dev:
1484		- cdev_del(&vfio.cdev);
1485		-err_base_cdev:
1486		- unregister_chrdev_region(vfio.devt, MINORMASK);
1487		-err_base_chrdev:
	1479	+err_cdev_add:
	1480	+ unregister_chrdev_region(vfio.group_devt, MINORMASK);
	1481	+err_alloc_chrdev:
1488	1482	class_destroy(vfio.class);
1489	1483	vfio.class = NULL;
1490	1484	err_class:
	1485	+ misc_deregister(&vfio_dev);
1491	1486	return ret;
1492	1487	}
1493	1488
1494	1489
...	...	@@ -1497,11 +1492,10 @@
1497	1492
1498	1493	idr_destroy(&vfio.group_idr);
1499	1494	cdev_del(&vfio.group_cdev);
1500		- device_destroy(vfio.class, vfio.devt);
1501		- cdev_del(&vfio.cdev);
1502		- unregister_chrdev_region(vfio.devt, MINORMASK);
	1495	+ unregister_chrdev_region(vfio.group_devt, MINORMASK);
1503	1496	class_destroy(vfio.class);
1504	1497	vfio.class = NULL;
	1498	+ misc_deregister(&vfio_dev);
1505	1499	}
1506	1500
1507	1501	module_init(vfio_init);
...	...	@@ -1511,4 +1505,6 @@
1511	1505	MODULE_LICENSE("GPL v2");
1512	1506	MODULE_AUTHOR(DRIVER_AUTHOR);
1513	1507	MODULE_DESCRIPTION(DRIVER_DESC);
	1508	+MODULE_ALIAS_MISCDEV(VFIO_MINOR);
	1509	+MODULE_ALIAS("devname:vfio/vfio");
...	...	@@ -30,6 +30,7 @@
30	30	#define STORE_QUEUE_MINOR 155
31	31	#define I2O_MINOR 166
32	32	#define MICROCODE_MINOR 184
	33	+#define VFIO_MINOR 196
33	34	#define TUN_MINOR 200
34	35	#define CUSE_MINOR 203
35	36	#define MWAVE_MINOR 219 /* ACP/Mwave Modem */