1 files changed, 38 insertions, 65 deletions

diff --git a/drivers/infiniband/core/uverbs_main.c b/drivers/infiniband/core/uverbs_main.c
index 381fd9c096ae..5b811bf574d6 100644
--- a/drivers/infiniband/core/uverbs_main.c
+++ b/drivers/infiniband/core/uverbs_main.c
@@ -62,14 +62,16 @@ MODULE_LICENSE("Dual BSD/GPL");
 enum {
 	IB_UVERBS_MAJOR       = 231,
 	IB_UVERBS_BASE_MINOR  = 192,
-	IB_UVERBS_MAX_DEVICES = 32
+	IB_UVERBS_MAX_DEVICES = RDMA_MAX_PORTS,
+	IB_UVERBS_NUM_FIXED_MINOR = 32,
+	IB_UVERBS_NUM_DYNAMIC_MINOR = IB_UVERBS_MAX_DEVICES - IB_UVERBS_NUM_FIXED_MINOR,
 };
 
 #define IB_UVERBS_BASE_DEV	MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
 
+static dev_t dynamic_uverbs_dev;
 static struct class *uverbs_class;
 
-static DEFINE_SPINLOCK(map_lock);
 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
 
 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
@@ -339,11 +341,11 @@ static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
 				    sizeof(struct ib_uverbs_comp_event_desc));
 }
 
-static unsigned int ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
+static __poll_t ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 					 struct file *filp,
 					 struct poll_table_struct *wait)
 {
-	unsigned int pollflags = 0;
+	__poll_t pollflags = 0;
 
 	poll_wait(filp, &ev_queue->poll_wait, wait);
 
@@ -355,13 +357,13 @@ static unsigned int ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 	return pollflags;
 }
 
-static unsigned int ib_uverbs_async_event_poll(struct file *filp,
+static __poll_t ib_uverbs_async_event_poll(struct file *filp,
 					       struct poll_table_struct *wait)
 {
 	return ib_uverbs_event_poll(filp->private_data, filp, wait);
 }
 
-static unsigned int ib_uverbs_comp_event_poll(struct file *filp,
+static __poll_t ib_uverbs_comp_event_poll(struct file *filp,
 					      struct poll_table_struct *wait)
 {
 	struct ib_uverbs_completion_event_file *comp_ev_file =
@@ -1005,34 +1007,6 @@ static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
 			 __stringify(IB_USER_VERBS_ABI_VERSION));
 
-static dev_t overflow_maj;
-static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
-
-/*
- * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
- * requesting a new major number and doubling the number of max devices we
- * support. It's stupid, but simple.
- */
-static int find_overflow_devnum(void)
-{
-	int ret;
-
-	if (!overflow_maj) {
-		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
-					  "infiniband_verbs");
-		if (ret) {
-			pr_err("user_verbs: couldn't register dynamic device number\n");
-			return ret;
-		}
-	}
-
-	ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
-	if (ret >= IB_UVERBS_MAX_DEVICES)
-		return -1;
-
-	return ret;
-}
-
 static void ib_uverbs_add_one(struct ib_device *device)
 {
 	int devnum;
@@ -1062,24 +1036,15 @@ static void ib_uverbs_add_one(struct ib_device *device)
 	INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
 	INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
 
-	spin_lock(&map_lock);
 	devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
-	if (devnum >= IB_UVERBS_MAX_DEVICES) {
-		spin_unlock(&map_lock);
-		devnum = find_overflow_devnum();
-		if (devnum < 0)
-			goto err;
-
-		spin_lock(&map_lock);
-		uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
-		base = devnum + overflow_maj;
-		set_bit(devnum, overflow_map);
-	} else {
-		uverbs_dev->devnum = devnum;
-		base = devnum + IB_UVERBS_BASE_DEV;
-		set_bit(devnum, dev_map);
-	}
-	spin_unlock(&map_lock);
+	if (devnum >= IB_UVERBS_MAX_DEVICES)
+		goto err;
+	uverbs_dev->devnum = devnum;
+	set_bit(devnum, dev_map);
+	if (devnum >= IB_UVERBS_NUM_FIXED_MINOR)
+		base = dynamic_uverbs_dev + devnum - IB_UVERBS_NUM_FIXED_MINOR;
+	else
+		base = IB_UVERBS_BASE_DEV + devnum;
 
 	rcu_assign_pointer(uverbs_dev->ib_dev, device);
 	uverbs_dev->num_comp_vectors = device->num_comp_vectors;
@@ -1124,10 +1089,7 @@ err_class:
 
 err_cdev:
 	cdev_del(&uverbs_dev->cdev);
-	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
-		clear_bit(devnum, dev_map);
-	else
-		clear_bit(devnum, overflow_map);
+	clear_bit(devnum, dev_map);
 
 err:
 	if (atomic_dec_and_test(&uverbs_dev->refcount))
@@ -1219,11 +1181,7 @@ static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
 	dev_set_drvdata(uverbs_dev->dev, NULL);
 	device_destroy(uverbs_class, uverbs_dev->cdev.dev);
 	cdev_del(&uverbs_dev->cdev);
-
-	if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
-		clear_bit(uverbs_dev->devnum, dev_map);
-	else
-		clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
+	clear_bit(uverbs_dev->devnum, dev_map);
 
 	if (device->disassociate_ucontext) {
 		/* We disassociate HW resources and immediately return.
@@ -1265,13 +1223,22 @@ static int __init ib_uverbs_init(void)
 {
 	int ret;
 
-	ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
+	ret = register_chrdev_region(IB_UVERBS_BASE_DEV,
+				     IB_UVERBS_NUM_FIXED_MINOR,
 				     "infiniband_verbs");
 	if (ret) {
 		pr_err("user_verbs: couldn't register device number\n");
 		goto out;
 	}
 
+	ret = alloc_chrdev_region(&dynamic_uverbs_dev, 0,
+				  IB_UVERBS_NUM_DYNAMIC_MINOR,
+				  "infiniband_verbs");
+	if (ret) {
+		pr_err("couldn't register dynamic device number\n");
+		goto out_alloc;
+	}
+
 	uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
 	if (IS_ERR(uverbs_class)) {
 		ret = PTR_ERR(uverbs_class);
@@ -1299,7 +1266,12 @@ out_class:
 	class_destroy(uverbs_class);
 
 out_chrdev:
-	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
+	unregister_chrdev_region(dynamic_uverbs_dev,
+				 IB_UVERBS_NUM_DYNAMIC_MINOR);
+
+out_alloc:
+	unregister_chrdev_region(IB_UVERBS_BASE_DEV,
+				 IB_UVERBS_NUM_FIXED_MINOR);
 
 out:
 	return ret;
@@ -1309,9 +1281,10 @@ static void __exit ib_uverbs_cleanup(void)
 {
 	ib_unregister_client(&uverbs_client);
 	class_destroy(uverbs_class);
-	unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
-	if (overflow_maj)
-		unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
+	unregister_chrdev_region(IB_UVERBS_BASE_DEV,
+				 IB_UVERBS_NUM_FIXED_MINOR);
+	unregister_chrdev_region(dynamic_uverbs_dev,
+				 IB_UVERBS_NUM_DYNAMIC_MINOR);
 }
 
 module_init(ib_uverbs_init);