text: /*
   * Copyright (c) 2004 Topspin Communications.  All rights reserved.
   * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
   *
   * This software is available to you under a choice of one of two
   * licenses.  You may choose to be licensed under the terms of the GNU
   * General Public License (GPL) Version 2, available from the file
   * COPYING in the main directory of this source tree, or the
   * OpenIB.org BSD license below:
   *
   *     Redistribution and use in source and binary forms, with or
   *     without modification, are permitted provided that the following
   *     conditions are met:
   *
   *      - Redistributions of source code must retain the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer.
   *
   *      - Redistributions in binary form must reproduce the above
   *        copyright notice, this list of conditions and the following
   *        disclaimer in the documentation and/or other materials
   *        provided with the distribution.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
   * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
   * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
   * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  
  #include <linux/module.h>
  #include <linux/string.h>
  #include <linux/errno.h>
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/init.h>
  #include <linux/mutex.h>
  #include <linux/workqueue.h>
  
  #include "core_priv.h"
  
  MODULE_AUTHOR("Roland Dreier");
  MODULE_DESCRIPTION("core kernel InfiniBand API");
  MODULE_LICENSE("Dual BSD/GPL");
  
  struct ib_client_data {
  	struct list_head  list;
  	struct ib_client *client;
  	void *            data;
  };
  
  static LIST_HEAD(device_list);
  static LIST_HEAD(client_list);
  
  /*
   * device_mutex protects access to both device_list and client_list.
   * There's no real point to using multiple locks or something fancier
   * like an rwsem: we always access both lists, and we're always
   * modifying one list or the other list.  In any case this is not a
   * hot path so there's no point in trying to optimize.
   */
  static DEFINE_MUTEX(device_mutex);
  
  static int ib_device_check_mandatory(struct ib_device *device)
  {
  #define IB_MANDATORY_FUNC(x) { offsetof(struct ib_device, x), #x }
  	static const struct {
  		size_t offset;
  		char  *name;
  	} mandatory_table[] = {
  		IB_MANDATORY_FUNC(query_device),
  		IB_MANDATORY_FUNC(query_port),
  		IB_MANDATORY_FUNC(query_pkey),
  		IB_MANDATORY_FUNC(query_gid),
  		IB_MANDATORY_FUNC(alloc_pd),
  		IB_MANDATORY_FUNC(dealloc_pd),
  		IB_MANDATORY_FUNC(create_ah),
  		IB_MANDATORY_FUNC(destroy_ah),
  		IB_MANDATORY_FUNC(create_qp),
  		IB_MANDATORY_FUNC(modify_qp),
  		IB_MANDATORY_FUNC(destroy_qp),
  		IB_MANDATORY_FUNC(post_send),
  		IB_MANDATORY_FUNC(post_recv),
  		IB_MANDATORY_FUNC(create_cq),
  		IB_MANDATORY_FUNC(destroy_cq),
  		IB_MANDATORY_FUNC(poll_cq),
  		IB_MANDATORY_FUNC(req_notify_cq),
  		IB_MANDATORY_FUNC(get_dma_mr),
  		IB_MANDATORY_FUNC(dereg_mr)
  	};
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(mandatory_table); ++i) {
  		if (!*(void **) ((void *) device + mandatory_table[i].offset)) {
  			printk(KERN_WARNING "Device %s is missing mandatory function %s\n",
  			       device->name, mandatory_table[i].name);
  			return -EINVAL;
  		}
  	}
  
  	return 0;
  }
  
  static struct ib_device *__ib_device_get_by_name(const char *name)
  {
  	struct ib_device *device;
  
  	list_for_each_entry(device, &device_list, core_list)
  		if (!strncmp(name, device->name, IB_DEVICE_NAME_MAX))
  			return device;
  
  	return NULL;
  }
  
  
  static int alloc_name(char *name)
  {
  	unsigned long *inuse;
  	char buf[IB_DEVICE_NAME_MAX];
  	struct ib_device *device;
  	int i;
  
  	inuse = (unsigned long *) get_zeroed_page(GFP_KERNEL);
  	if (!inuse)
  		return -ENOMEM;
  
  	list_for_each_entry(device, &device_list, core_list) {
  		if (!sscanf(device->name, name, &i))
  			continue;
  		if (i < 0 || i >= PAGE_SIZE * 8)
  			continue;
  		snprintf(buf, sizeof buf, name, i);
  		if (!strncmp(buf, device->name, IB_DEVICE_NAME_MAX))
  			set_bit(i, inuse);
  	}
  
  	i = find_first_zero_bit(inuse, PAGE_SIZE * 8);
  	free_page((unsigned long) inuse);
  	snprintf(buf, sizeof buf, name, i);
  
  	if (__ib_device_get_by_name(buf))
  		return -ENFILE;
  
  	strlcpy(name, buf, IB_DEVICE_NAME_MAX);
  	return 0;
  }
  
  static int start_port(struct ib_device *device)
  {
  	return (device->node_type == RDMA_NODE_IB_SWITCH) ? 0 : 1;
  }
  
  
  static int end_port(struct ib_device *device)
  {
  	return (device->node_type == RDMA_NODE_IB_SWITCH) ?
  		0 : device->phys_port_cnt;
  }
  
  /**
   * ib_alloc_device - allocate an IB device struct
   * @size:size of structure to allocate
   *
   * Low-level drivers should use ib_alloc_device() to allocate &struct
   * ib_device.  @size is the size of the structure to be allocated,
   * including any private data used by the low-level driver.
   * ib_dealloc_device() must be used to free structures allocated with
   * ib_alloc_device().
   */
  struct ib_device *ib_alloc_device(size_t size)
  {
  	BUG_ON(size < sizeof (struct ib_device));
  
  	return kzalloc(size, GFP_KERNEL);
  }
  EXPORT_SYMBOL(ib_alloc_device);
  
  /**
   * ib_dealloc_device - free an IB device struct
   * @device:structure to free
   *
   * Free a structure allocated with ib_alloc_device().
   */
  void ib_dealloc_device(struct ib_device *device)
  {
  	if (device->reg_state == IB_DEV_UNINITIALIZED) {
  		kfree(device);
  		return;
  	}
  
  	BUG_ON(device->reg_state != IB_DEV_UNREGISTERED);
  
  	kobject_put(&device->dev.kobj);
  }
  EXPORT_SYMBOL(ib_dealloc_device);
  
  static int add_client_context(struct ib_device *device, struct ib_client *client)
  {
  	struct ib_client_data *context;
  	unsigned long flags;
  
  	context = kmalloc(sizeof *context, GFP_KERNEL);
  	if (!context) {
  		printk(KERN_WARNING "Couldn't allocate client context for %s/%s\n",
  		       device->name, client->name);
  		return -ENOMEM;
  	}
  
  	context->client = client;
  	context->data   = NULL;
  
  	spin_lock_irqsave(&device->client_data_lock, flags);
  	list_add(&context->list, &device->client_data_list);
  	spin_unlock_irqrestore(&device->client_data_lock, flags);
  
  	return 0;
  }
  
  static int read_port_table_lengths(struct ib_device *device)
  {
  	struct ib_port_attr *tprops = NULL;
  	int num_ports, ret = -ENOMEM;
  	u8 port_index;
  
  	tprops = kmalloc(sizeof *tprops, GFP_KERNEL);
  	if (!tprops)
  		goto out;
  
  	num_ports = end_port(device) - start_port(device) + 1;
  
  	device->pkey_tbl_len = kmalloc(sizeof *device->pkey_tbl_len * num_ports,
  				       GFP_KERNEL);
  	device->gid_tbl_len = kmalloc(sizeof *device->gid_tbl_len * num_ports,
  				      GFP_KERNEL);
  	if (!device->pkey_tbl_len || !device->gid_tbl_len)
  		goto err;
  
  	for (port_index = 0; port_index < num_ports; ++port_index) {
  		ret = ib_query_port(device, port_index + start_port(device),
  					tprops);
  		if (ret)
  			goto err;
  		device->pkey_tbl_len[port_index] = tprops->pkey_tbl_len;
  		device->gid_tbl_len[port_index]  = tprops->gid_tbl_len;
  	}
  
  	ret = 0;
  	goto out;
  
  err:
  	kfree(device->gid_tbl_len);
  	kfree(device->pkey_tbl_len);
  out:
  	kfree(tprops);
  	return ret;
  }
  
  /**
   * ib_register_device - Register an IB device with IB core
   * @device:Device to register
   *
   * Low-level drivers use ib_register_device() to register their
   * devices with the IB core.  All registered clients will receive a
   * callback for each device that is added. @device must be allocated
   * with ib_alloc_device().
   */
  int ib_register_device(struct ib_device *device)
  {
  	int ret;
  
  	mutex_lock(&device_mutex);
  
  	if (strchr(device->name, '%')) {
  		ret = alloc_name(device->name);
  		if (ret)
  			goto out;
  	}
  
  	if (ib_device_check_mandatory(device)) {
  		ret = -EINVAL;
  		goto out;
  	}
  
  	INIT_LIST_HEAD(&device->event_handler_list);
  	INIT_LIST_HEAD(&device->client_data_list);
  	spin_lock_init(&device->event_handler_lock);
  	spin_lock_init(&device->client_data_lock);
  
  	ret = read_port_table_lengths(device);
  	if (ret) {
  		printk(KERN_WARNING "Couldn't create table lengths cache for device %s\n",
  		       device->name);
  		goto out;
  	}
  
  	ret = ib_device_register_sysfs(device);
  	if (ret) {
  		printk(KERN_WARNING "Couldn't register device %s with driver model\n",
  		       device->name);
  		kfree(device->gid_tbl_len);
  		kfree(device->pkey_tbl_len);
  		goto out;
  	}
  
  	list_add_tail(&device->core_list, &device_list);
  
  	device->reg_state = IB_DEV_REGISTERED;
  
  	{
  		struct ib_client *client;
  
  		list_for_each_entry(client, &client_list, list)
  			if (client->add && !add_client_context(device, client))
  				client->add(device);
  	}
  
   out:
  	mutex_unlock(&device_mutex);
  	return ret;
  }
  EXPORT_SYMBOL(ib_register_device);
  
  /**
   * ib_unregister_device - Unregister an IB device
   * @device:Device to unregister
   *
   * Unregister an IB device.  All clients will receive a remove callback.
   */
  void ib_unregister_device(struct ib_device *device)
  {
  	struct ib_client *client;
  	struct ib_client_data *context, *tmp;
  	unsigned long flags;
  
  	mutex_lock(&device_mutex);
  
  	list_for_each_entry_reverse(client, &client_list, list)
  		if (client->remove)
  			client->remove(device);
  
  	list_del(&device->core_list);
  
  	kfree(device->gid_tbl_len);
  	kfree(device->pkey_tbl_len);
  
  	mutex_unlock(&device_mutex);
  
  	ib_device_unregister_sysfs(device);
  
  	spin_lock_irqsave(&device->client_data_lock, flags);
  	list_for_each_entry_safe(context, tmp, &device->client_data_list, list)
  		kfree(context);
  	spin_unlock_irqrestore(&device->client_data_lock, flags);
  
  	device->reg_state = IB_DEV_UNREGISTERED;
  }
  EXPORT_SYMBOL(ib_unregister_device);
  
  /**
   * ib_register_client - Register an IB client
   * @client:Client to register
   *
   * Upper level users of the IB drivers can use ib_register_client() to
   * register callbacks for IB device addition and removal.  When an IB
   * device is added, each registered client's add method will be called
   * (in the order the clients were registered), and when a device is
   * removed, each client's remove method will be called (in the reverse
   * order that clients were registered).  In addition, when
   * ib_register_client() is called, the client will receive an add
   * callback for all devices already registered.
   */
  int ib_register_client(struct ib_client *client)
  {
  	struct ib_device *device;
  
  	mutex_lock(&device_mutex);
  
  	list_add_tail(&client->list, &client_list);
  	list_for_each_entry(device, &device_list, core_list)
  		if (client->add && !add_client_context(device, client))
  			client->add(device);
  
  	mutex_unlock(&device_mutex);
  
  	return 0;
  }
  EXPORT_SYMBOL(ib_register_client);
  
  /**
   * ib_unregister_client - Unregister an IB client
   * @client:Client to unregister
   *
   * Upper level users use ib_unregister_client() to remove their client
   * registration.  When ib_unregister_client() is called, the client
   * will receive a remove callback for each IB device still registered.
   */
  void ib_unregister_client(struct ib_client *client)
  {
  	struct ib_client_data *context, *tmp;
  	struct ib_device *device;
  	unsigned long flags;
  
  	mutex_lock(&device_mutex);
  
  	list_for_each_entry(device, &device_list, core_list) {
  		if (client->remove)
  			client->remove(device);
  
  		spin_lock_irqsave(&device->client_data_lock, flags);
  		list_for_each_entry_safe(context, tmp, &device->client_data_list, list)
  			if (context->client == client) {
  				list_del(&context->list);
  				kfree(context);
  			}
  		spin_unlock_irqrestore(&device->client_data_lock, flags);
  	}
  	list_del(&client->list);
  
  	mutex_unlock(&device_mutex);
  }
  EXPORT_SYMBOL(ib_unregister_client);
  
  /**
   * ib_get_client_data - Get IB client context
   * @device:Device to get context for
   * @client:Client to get context for
   *
   * ib_get_client_data() returns client context set with
   * ib_set_client_data().
   */
  void *ib_get_client_data(struct ib_device *device, struct ib_client *client)
  {
  	struct ib_client_data *context;
  	void *ret = NULL;
  	unsigned long flags;
  
  	spin_lock_irqsave(&device->client_data_lock, flags);
  	list_for_each_entry(context, &device->client_data_list, list)
  		if (context->client == client) {
  			ret = context->data;
  			break;
  		}
  	spin_unlock_irqrestore(&device->client_data_lock, flags);
  
  	return ret;
  }
  EXPORT_SYMBOL(ib_get_client_data);
  
  /**
   * ib_set_client_data - Set IB client context
   * @device:Device to set context for
   * @client:Client to set context for
   * @data:Context to set
   *
   * ib_set_client_data() sets client context that can be retrieved with
   * ib_get_client_data().
   */
  void ib_set_client_data(struct ib_device *device, struct ib_client *client,
  			void *data)
  {
  	struct ib_client_data *context;
  	unsigned long flags;
  
  	spin_lock_irqsave(&device->client_data_lock, flags);
  	list_for_each_entry(context, &device->client_data_list, list)
  		if (context->client == client) {
  			context->data = data;
  			goto out;
  		}
  
  	printk(KERN_WARNING "No client context found for %s/%s\n",
  	       device->name, client->name);
  
  out:
  	spin_unlock_irqrestore(&device->client_data_lock, flags);
  }
  EXPORT_SYMBOL(ib_set_client_data);
  
  /**
   * ib_register_event_handler - Register an IB event handler
   * @event_handler:Handler to register
   *
   * ib_register_event_handler() registers an event handler that will be
   * called back when asynchronous IB events occur (as defined in
   * chapter 11 of the InfiniBand Architecture Specification).  This
   * callback may occur in interrupt context.
   */
  int ib_register_event_handler  (struct ib_event_handler *event_handler)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&event_handler->device->event_handler_lock, flags);
  	list_add_tail(&event_handler->list,
  		      &event_handler->device->event_handler_list);
  	spin_unlock_irqrestore(&event_handler->device->event_handler_lock, flags);
  
  	return 0;
  }
  EXPORT_SYMBOL(ib_register_event_handler);
  
  /**
   * ib_unregister_event_handler - Unregister an event handler
   * @event_handler:Handler to unregister
   *
   * Unregister an event handler registered with
   * ib_register_event_handler().
   */
  int ib_unregister_event_handler(struct ib_event_handler *event_handler)
  {
  	unsigned long flags;
  
  	spin_lock_irqsave(&event_handler->device->event_handler_lock, flags);
  	list_del(&event_handler->list);
  	spin_unlock_irqrestore(&event_handler->device->event_handler_lock, flags);
  
  	return 0;
  }
  EXPORT_SYMBOL(ib_unregister_event_handler);
  
  /**
   * ib_dispatch_event - Dispatch an asynchronous event
   * @event:Event to dispatch
   *
   * Low-level drivers must call ib_dispatch_event() to dispatch the
   * event to all registered event handlers when an asynchronous event
   * occurs.
   */
  void ib_dispatch_event(struct ib_event *event)
  {
  	unsigned long flags;
  	struct ib_event_handler *handler;
  
  	spin_lock_irqsave(&event->device->event_handler_lock, flags);
  
  	list_for_each_entry(handler, &event->device->event_handler_list, list)
  		handler->handler(handler, event);
  
  	spin_unlock_irqrestore(&event->device->event_handler_lock, flags);
  }
  EXPORT_SYMBOL(ib_dispatch_event);
  
  /**
   * ib_query_device - Query IB device attributes
   * @device:Device to query
   * @device_attr:Device attributes
   *
   * ib_query_device() returns the attributes of a device through the
   * @device_attr pointer.
   */
  int ib_query_device(struct ib_device *device,
  		    struct ib_device_attr *device_attr)
  {
  	return device->query_device(device, device_attr);
  }
  EXPORT_SYMBOL(ib_query_device);
  
  /**
   * ib_query_port - Query IB port attributes
   * @device:Device to query
   * @port_num:Port number to query
   * @port_attr:Port attributes
   *
   * ib_query_port() returns the attributes of a port through the
   * @port_attr pointer.
   */
  int ib_query_port(struct ib_device *device,
  		  u8 port_num,
  		  struct ib_port_attr *port_attr)
  {
  	if (port_num < start_port(device) || port_num > end_port(device))
  		return -EINVAL;
  
  	return device->query_port(device, port_num, port_attr);
  }
  EXPORT_SYMBOL(ib_query_port);
  
  /**
   * ib_query_gid - Get GID table entry
   * @device:Device to query
   * @port_num:Port number to query
   * @index:GID table index to query
   * @gid:Returned GID
   *
   * ib_query_gid() fetches the specified GID table entry.
   */
  int ib_query_gid(struct ib_device *device,
  		 u8 port_num, int index, union ib_gid *gid)
  {
  	return device->query_gid(device, port_num, index, gid);
  }
  EXPORT_SYMBOL(ib_query_gid);
  
  /**
   * ib_query_pkey - Get P_Key table entry
   * @device:Device to query
   * @port_num:Port number to query
   * @index:P_Key table index to query
   * @pkey:Returned P_Key
   *
   * ib_query_pkey() fetches the specified P_Key table entry.
   */
  int ib_query_pkey(struct ib_device *device,
  		  u8 port_num, u16 index, u16 *pkey)
  {
  	return device->query_pkey(device, port_num, index, pkey);
  }
  EXPORT_SYMBOL(ib_query_pkey);
  
  /**
   * ib_modify_device - Change IB device attributes
   * @device:Device to modify
   * @device_modify_mask:Mask of attributes to change
   * @device_modify:New attribute values
   *
   * ib_modify_device() changes a device's attributes as specified by
   * the @device_modify_mask and @device_modify structure.
   */
  int ib_modify_device(struct ib_device *device,
  		     int device_modify_mask,
  		     struct ib_device_modify *device_modify)
  {
  	return device->modify_device(device, device_modify_mask,
  				     device_modify);
  }
  EXPORT_SYMBOL(ib_modify_device);
  
  /**
   * ib_modify_port - Modifies the attributes for the specified port.
   * @device: The device to modify.
   * @port_num: The number of the port to modify.
   * @port_modify_mask: Mask used to specify which attributes of the port
   *   to change.
   * @port_modify: New attribute values for the port.
   *
   * ib_modify_port() changes a port's attributes as specified by the
   * @port_modify_mask and @port_modify structure.
   */
  int ib_modify_port(struct ib_device *device,
  		   u8 port_num, int port_modify_mask,
  		   struct ib_port_modify *port_modify)
  {
  	if (port_num < start_port(device) || port_num > end_port(device))
  		return -EINVAL;
  
  	return device->modify_port(device, port_num, port_modify_mask,
  				   port_modify);
  }
  EXPORT_SYMBOL(ib_modify_port);
  
  /**
   * ib_find_gid - Returns the port number and GID table index where
   *   a specified GID value occurs.
   * @device: The device to query.
   * @gid: The GID value to search for.
   * @port_num: The port number of the device where the GID value was found.
   * @index: The index into the GID table where the GID was found.  This
   *   parameter may be NULL.
   */
  int ib_find_gid(struct ib_device *device, union ib_gid *gid,
  		u8 *port_num, u16 *index)
  {
  	union ib_gid tmp_gid;
  	int ret, port, i;
  
  	for (port = start_port(device); port <= end_port(device); ++port) {
  		for (i = 0; i < device->gid_tbl_len[port - start_port(device)]; ++i) {
  			ret = ib_query_gid(device, port, i, &tmp_gid);
  			if (ret)
  				return ret;
  			if (!memcmp(&tmp_gid, gid, sizeof *gid)) {
  				*port_num = port;
  				if (index)
  					*index = i;
  				return 0;
  			}
  		}
  	}
  
  	return -ENOENT;
  }
  EXPORT_SYMBOL(ib_find_gid);
  
  /**
   * ib_find_pkey - Returns the PKey table index where a specified
   *   PKey value occurs.
   * @device: The device to query.
   * @port_num: The port number of the device to search for the PKey.
   * @pkey: The PKey value to search for.
   * @index: The index into the PKey table where the PKey was found.
   */
  int ib_find_pkey(struct ib_device *device,
  		 u8 port_num, u16 pkey, u16 *index)
  {
  	int ret, i;
  	u16 tmp_pkey;
  
  	for (i = 0; i < device->pkey_tbl_len[port_num - start_port(device)]; ++i) {
  		ret = ib_query_pkey(device, port_num, i, &tmp_pkey);
  		if (ret)
  			return ret;
  
  		if ((pkey & 0x7fff) == (tmp_pkey & 0x7fff)) {
  			*index = i;
  			return 0;
  		}
  	}
  
  	return -ENOENT;
  }
  EXPORT_SYMBOL(ib_find_pkey);
  
  static int __init ib_core_init(void)
  {
  	int ret;
  
  	ret = ib_sysfs_setup();
  	if (ret)
  		printk(KERN_WARNING "Couldn't create InfiniBand device class\n");
  
  	ret = ib_cache_setup();
  	if (ret) {
  		printk(KERN_WARNING "Couldn't set up InfiniBand P_Key/GID cache\n");
  		ib_sysfs_cleanup();
  	}
  
  	return ret;
  }
  
  static void __exit ib_core_cleanup(void)
  {
  	ib_cache_cleanup();
  	ib_sysfs_cleanup();
  	/* Make sure that any pending umem accounting work is done. */
  	flush_scheduled_work();
  }
  
  module_init(ib_core_init);
  module_exit(ib_core_cleanup);
  