/*
   * IEEE 1394 for Linux
   *
   * Copyright (C) 1999 Andreas E. Bombe
   *
   * This code is licensed under the GPL.  See the file COPYING in the root
   * directory of the kernel sources for details.
   *
   *
   * Contributions:
   *
   * Christian Toegel <christian.toegel@gmx.at>
   *        unregister address space
   *
   * Manfred Weihs <weihs@ict.tuwien.ac.at>
   *        unregister address space
   *
   */

  #include <linux/slab.h>
  #include <linux/list.h>
  #include <linux/bitops.h>
  
  #include "ieee1394.h"
  #include "ieee1394_types.h"
  #include "hosts.h"
  #include "ieee1394_core.h"
  #include "highlevel.h"
  #include "nodemgr.h"
  
  
  struct hl_host_info {
  	struct list_head list;
  	struct hpsb_host *host;
  	size_t size;
  	unsigned long key;
  	void *data;
  };
  
  
  static LIST_HEAD(hl_drivers);
  static DECLARE_RWSEM(hl_drivers_sem);
  
  static LIST_HEAD(hl_irqs);
  static DEFINE_RWLOCK(hl_irqs_lock);
  
  static DEFINE_RWLOCK(addr_space_lock);

  
  static struct hl_host_info *hl_get_hostinfo(struct hpsb_highlevel *hl,

  					    struct hpsb_host *host)

  {
  	struct hl_host_info *hi = NULL;
  
  	if (!hl || !host)
  		return NULL;
  
  	read_lock(&hl->host_info_lock);
  	list_for_each_entry(hi, &hl->host_info_list, list) {
  		if (hi->host == host) {
  			read_unlock(&hl->host_info_lock);
  			return hi;
  		}
  	}
  	read_unlock(&hl->host_info_lock);

  	return NULL;
  }

  /**
   * hpsb_get_hostinfo - retrieve a hostinfo pointer bound to this driver/host
   *
   * Returns a per @host and @hl driver data structure that was previously stored
   * by hpsb_create_hostinfo.
   */

  void *hpsb_get_hostinfo(struct hpsb_highlevel *hl, struct hpsb_host *host)
  {
  	struct hl_host_info *hi = hl_get_hostinfo(hl, host);

  	return hi ? hi->data : NULL;

  }

  /**
   * hpsb_create_hostinfo - allocate a hostinfo pointer bound to this driver/host
   *
   * Allocate a hostinfo pointer backed by memory with @data_size and bind it to
   * to this @hl driver and @host.  If @data_size is zero, then the return here is
   * only valid for error checking.
   */

  void *hpsb_create_hostinfo(struct hpsb_highlevel *hl, struct hpsb_host *host,
  			   size_t data_size)
  {
  	struct hl_host_info *hi;
  	void *data;
  	unsigned long flags;
  
  	hi = hl_get_hostinfo(hl, host);
  	if (hi) {

  		HPSB_ERR("%s called hpsb_create_hostinfo when hostinfo already"
  			 " exists", hl->name);

  		return NULL;
  	}

  	hi = kzalloc(sizeof(*hi) + data_size, GFP_ATOMIC);

  	if (!hi)
  		return NULL;

  	if (data_size) {
  		data = hi->data = hi + 1;
  		hi->size = data_size;
  	} else
  		data = hi;
  
  	hi->host = host;
  
  	write_lock_irqsave(&hl->host_info_lock, flags);
  	list_add_tail(&hi->list, &hl->host_info_list);
  	write_unlock_irqrestore(&hl->host_info_lock, flags);
  
  	return data;
  }

  /**
   * hpsb_set_hostinfo - set the hostinfo pointer to something useful
   *
   * Usually follows a call to hpsb_create_hostinfo, where the size is 0.
   */

  int hpsb_set_hostinfo(struct hpsb_highlevel *hl, struct hpsb_host *host,
  		      void *data)
  {
  	struct hl_host_info *hi;
  
  	hi = hl_get_hostinfo(hl, host);
  	if (hi) {
  		if (!hi->size && !hi->data) {
  			hi->data = data;
  			return 0;
  		} else

  			HPSB_ERR("%s called hpsb_set_hostinfo when hostinfo "
  				 "already has data", hl->name);

  	} else
  		HPSB_ERR("%s called hpsb_set_hostinfo when no hostinfo exists",
  			 hl->name);

  	return -EINVAL;
  }

  /**
   * hpsb_destroy_hostinfo - free and remove a hostinfo pointer
   *
   * Free and remove the hostinfo pointer bound to this @hl driver and @host.
   */

  void hpsb_destroy_hostinfo(struct hpsb_highlevel *hl, struct hpsb_host *host)
  {
  	struct hl_host_info *hi;
  
  	hi = hl_get_hostinfo(hl, host);
  	if (hi) {
  		unsigned long flags;
  		write_lock_irqsave(&hl->host_info_lock, flags);
  		list_del(&hi->list);
  		write_unlock_irqrestore(&hl->host_info_lock, flags);
  		kfree(hi);
  	}

  	return;
  }

  /**
   * hpsb_set_hostinfo_key - set an alternate lookup key for an hostinfo
   *
   * Sets an alternate lookup key for the hostinfo bound to this @hl driver and
   * @host.
   */

  void hpsb_set_hostinfo_key(struct hpsb_highlevel *hl, struct hpsb_host *host,
  			   unsigned long key)

  {
  	struct hl_host_info *hi;
  
  	hi = hl_get_hostinfo(hl, host);
  	if (hi)
  		hi->key = key;

  	return;
  }

  /**
   * hpsb_get_hostinfo_bykey - retrieve a hostinfo pointer by its alternate key
   */

  void *hpsb_get_hostinfo_bykey(struct hpsb_highlevel *hl, unsigned long key)
  {
  	struct hl_host_info *hi;
  	void *data = NULL;
  
  	if (!hl)
  		return NULL;
  
  	read_lock(&hl->host_info_lock);
  	list_for_each_entry(hi, &hl->host_info_list, list) {
  		if (hi->key == key) {
  			data = hi->data;
  			break;
  		}
  	}
  	read_unlock(&hl->host_info_lock);

  	return data;
  }

  static int highlevel_for_each_host_reg(struct hpsb_host *host, void *__data)
  {
  	struct hpsb_highlevel *hl = __data;
  
  	hl->add_host(host);

  	if (host->update_config_rom && hpsb_update_config_rom_image(host) < 0)
  		HPSB_ERR("Failed to generate Configuration ROM image for host "
  			 "%s-%d", hl->name, host->id);

  	return 0;
  }

  /**
   * hpsb_register_highlevel - register highlevel driver
   *
   * The name pointer in @hl has to stay valid at all times because the string is
   * not copied.
   */

  void hpsb_register_highlevel(struct hpsb_highlevel *hl)
  {

  	unsigned long flags;

  	hpsb_init_highlevel(hl);

  	INIT_LIST_HEAD(&hl->addr_list);

  
  	down_write(&hl_drivers_sem);

  	list_add_tail(&hl->hl_list, &hl_drivers);

  	up_write(&hl_drivers_sem);

  	write_lock_irqsave(&hl_irqs_lock, flags);

  	list_add_tail(&hl->irq_list, &hl_irqs);

  	write_unlock_irqrestore(&hl_irqs_lock, flags);

  
  	if (hl->add_host)
  		nodemgr_for_each_host(hl, highlevel_for_each_host_reg);

  	return;

  }
  
  static void __delete_addr(struct hpsb_address_serve *as)
  {
  	list_del(&as->host_list);
  	list_del(&as->hl_list);
  	kfree(as);
  }

  static void __unregister_host(struct hpsb_highlevel *hl, struct hpsb_host *host,
  			      int update_cr)

  {
  	unsigned long flags;
  	struct list_head *lh, *next;
  	struct hpsb_address_serve *as;
  
  	/* First, let the highlevel driver unreg */
  	if (hl->remove_host)
  		hl->remove_host(host);
  
  	/* Remove any addresses that are matched for this highlevel driver
  	 * and this particular host. */
  	write_lock_irqsave(&addr_space_lock, flags);
  	list_for_each_safe (lh, next, &hl->addr_list) {
  		as = list_entry(lh, struct hpsb_address_serve, hl_list);

  		if (as->host == host)
  			__delete_addr(as);
  	}
  	write_unlock_irqrestore(&addr_space_lock, flags);
  
  	/* Now update the config-rom to reflect anything removed by the
  	 * highlevel driver. */

  	if (update_cr && host->update_config_rom &&
  	    hpsb_update_config_rom_image(host) < 0)
  		HPSB_ERR("Failed to generate Configuration ROM image for host "
  			 "%s-%d", hl->name, host->id);

  	/* Finally remove all the host info associated between these two. */

  	hpsb_destroy_hostinfo(hl, host);
  }
  
  static int highlevel_for_each_host_unreg(struct hpsb_host *host, void *__data)
  {
  	struct hpsb_highlevel *hl = __data;
  
  	__unregister_host(hl, host, 1);

  	return 0;
  }

  /**
   * hpsb_unregister_highlevel - unregister highlevel driver
   */

  void hpsb_unregister_highlevel(struct hpsb_highlevel *hl)
  {

  	unsigned long flags;
  
  	write_lock_irqsave(&hl_irqs_lock, flags);

  	list_del(&hl->irq_list);

  	write_unlock_irqrestore(&hl_irqs_lock, flags);

  
  	down_write(&hl_drivers_sem);

  	list_del(&hl->hl_list);

  	up_write(&hl_drivers_sem);
  
  	nodemgr_for_each_host(hl, highlevel_for_each_host_unreg);
  }

  /**
   * hpsb_allocate_and_register_addrspace - alloc' and reg' a host address space
   *
   * @start and @end are 48 bit pointers and have to be quadlet aligned.
   * @end points to the first address behind the handled addresses.  This
   * function can be called multiple times for a single hpsb_highlevel @hl to
   * implement sparse register sets.  The requested region must not overlap any
   * previously allocated region, otherwise registering will fail.
   *
   * It returns true for successful allocation.  Address spaces can be
   * unregistered with hpsb_unregister_addrspace.  All remaining address spaces
   * are automatically deallocated together with the hpsb_highlevel @hl.
   */

  u64 hpsb_allocate_and_register_addrspace(struct hpsb_highlevel *hl,
  					 struct hpsb_host *host,

  					 const struct hpsb_address_ops *ops,

  					 u64 size, u64 alignment,
  					 u64 start, u64 end)
  {
  	struct hpsb_address_serve *as, *a1, *a2;
  	struct list_head *entry;

  	u64 retval = CSR1212_INVALID_ADDR_SPACE;

  	unsigned long flags;
  	u64 align_mask = ~(alignment - 1);
  
  	if ((alignment & 3) || (alignment > 0x800000000000ULL) ||

  	    (hweight64(alignment) != 1)) {

  		HPSB_ERR("%s called with invalid alignment: 0x%048llx",

  			 __func__, (unsigned long long)alignment);

  		return retval;
  	}

  	/* default range,
  	 * avoids controller's posted write area (see OHCI 1.1 clause 1.5) */

  	if (start == CSR1212_INVALID_ADDR_SPACE &&
  	    end   == CSR1212_INVALID_ADDR_SPACE) {

  		start = host->middle_addr_space;

  		end   = CSR1212_ALL_SPACE_END;

  	}

  	if (((start|end) & ~align_mask) || (start >= end) ||
  	    (end > CSR1212_ALL_SPACE_END)) {
  		HPSB_ERR("%s called with invalid addresses "

  			 "(start = %012Lx  end = %012Lx)", __func__,

  			 (unsigned long long)start,(unsigned long long)end);

  		return retval;
  	}

  	as = kmalloc(sizeof(*as), GFP_KERNEL);
  	if (!as)

  		return retval;

  
  	INIT_LIST_HEAD(&as->host_list);
  	INIT_LIST_HEAD(&as->hl_list);
  	as->op = ops;
  	as->host = host;
  
  	write_lock_irqsave(&addr_space_lock, flags);

  	list_for_each(entry, &host->addr_space) {
  		u64 a1sa, a1ea;
  		u64 a2sa, a2ea;
  
  		a1 = list_entry(entry, struct hpsb_address_serve, host_list);

  		a2 = list_entry(entry->next, struct hpsb_address_serve,
  				host_list);

  
  		a1sa = a1->start & align_mask;
  		a1ea = (a1->end + alignment -1) & align_mask;
  		a2sa = a2->start & align_mask;
  		a2ea = (a2->end + alignment -1) & align_mask;

  		if ((a2sa - a1ea >= size) && (a2sa - start >= size) &&
  		    (a2sa > start)) {

  			as->start = max(start, a1ea);
  			as->end = as->start + size;
  			list_add(&as->host_list, entry);
  			list_add_tail(&as->hl_list, &hl->addr_list);
  			retval = as->start;
  			break;
  		}
  	}

  	write_unlock_irqrestore(&addr_space_lock, flags);

  	if (retval == CSR1212_INVALID_ADDR_SPACE)

  		kfree(as);

  	return retval;
  }

  /**
   * hpsb_register_addrspace - register a host address space
   *
   * @start and @end are 48 bit pointers and have to be quadlet aligned.
   * @end points to the first address behind the handled addresses.  This
   * function can be called multiple times for a single hpsb_highlevel @hl to
   * implement sparse register sets.  The requested region must not overlap any
   * previously allocated region, otherwise registering will fail.
   *
   * It returns true for successful allocation.  Address spaces can be
   * unregistered with hpsb_unregister_addrspace.  All remaining address spaces
   * are automatically deallocated together with the hpsb_highlevel @hl.
   */

  int hpsb_register_addrspace(struct hpsb_highlevel *hl, struct hpsb_host *host,

  			    const struct hpsb_address_ops *ops,
  			    u64 start, u64 end)

  {

  	struct hpsb_address_serve *as;

  	struct list_head *lh;

  	int retval = 0;
  	unsigned long flags;

  	if (((start|end) & 3) || (start >= end) ||
  	    (end > CSR1212_ALL_SPACE_END)) {

  		HPSB_ERR("%s called with invalid addresses", __func__);

  		return 0;
  	}

  	as = kmalloc(sizeof(*as), GFP_KERNEL);

  	if (!as)
  		return 0;

  	INIT_LIST_HEAD(&as->host_list);
  	INIT_LIST_HEAD(&as->hl_list);
  	as->op = ops;
  	as->start = start;
  	as->end = end;

  	as->host = host;
  
  	write_lock_irqsave(&addr_space_lock, flags);

  	list_for_each(lh, &host->addr_space) {
  		struct hpsb_address_serve *as_this =
  			list_entry(lh, struct hpsb_address_serve, host_list);
  		struct hpsb_address_serve *as_next =

  			list_entry(lh->next, struct hpsb_address_serve,
  				   host_list);

  
  		if (as_this->end > as->start)
  			break;
  
  		if (as_next->start >= as->end) {
  			list_add(&as->host_list, lh);
  			list_add_tail(&as->hl_list, &hl->addr_list);
  			retval = 1;
  			break;
  		}
  	}
  	write_unlock_irqrestore(&addr_space_lock, flags);
  
  	if (retval == 0)
  		kfree(as);

  	return retval;

  }
  
  int hpsb_unregister_addrspace(struct hpsb_highlevel *hl, struct hpsb_host *host,

  			      u64 start)

  {

  	int retval = 0;
  	struct hpsb_address_serve *as;
  	struct list_head *lh, *next;
  	unsigned long flags;

  	write_lock_irqsave(&addr_space_lock, flags);

  	list_for_each_safe (lh, next, &hl->addr_list) {

  		as = list_entry(lh, struct hpsb_address_serve, hl_list);
  		if (as->start == start && as->host == host) {

  			__delete_addr(as);

  			retval = 1;
  			break;
  		}
  	}
  	write_unlock_irqrestore(&addr_space_lock, flags);
  	return retval;

  }

  static const struct hpsb_address_ops dummy_ops;

  
  /* dummy address spaces as lower and upper bounds of the host's a.s. list */

  static void init_hpsb_highlevel(struct hpsb_host *host)
  {

  	INIT_LIST_HEAD(&host->dummy_zero_addr.host_list);
  	INIT_LIST_HEAD(&host->dummy_zero_addr.hl_list);
  	INIT_LIST_HEAD(&host->dummy_max_addr.host_list);
  	INIT_LIST_HEAD(&host->dummy_max_addr.hl_list);

  	host->dummy_zero_addr.op = host->dummy_max_addr.op = &dummy_ops;

  	host->dummy_zero_addr.start = host->dummy_zero_addr.end = 0;
  	host->dummy_max_addr.start = host->dummy_max_addr.end = ((u64) 1) << 48;

  	list_add_tail(&host->dummy_zero_addr.host_list, &host->addr_space);
  	list_add_tail(&host->dummy_max_addr.host_list, &host->addr_space);

  }
  
  void highlevel_add_host(struct hpsb_host *host)
  {

  	struct hpsb_highlevel *hl;

  
  	init_hpsb_highlevel(host);
  
  	down_read(&hl_drivers_sem);

  	list_for_each_entry(hl, &hl_drivers, hl_list) {

  		if (hl->add_host)
  			hl->add_host(host);

  	}

  	up_read(&hl_drivers_sem);
  	if (host->update_config_rom && hpsb_update_config_rom_image(host) < 0)
  		HPSB_ERR("Failed to generate Configuration ROM image for host "
  			 "%s-%d", hl->name, host->id);

  }
  
  void highlevel_remove_host(struct hpsb_host *host)
  {

  	struct hpsb_highlevel *hl;

  
  	down_read(&hl_drivers_sem);
  	list_for_each_entry(hl, &hl_drivers, hl_list)
  		__unregister_host(hl, host, 0);
  	up_read(&hl_drivers_sem);
  }
  
  void highlevel_host_reset(struct hpsb_host *host)
  {

  	unsigned long flags;

  	struct hpsb_highlevel *hl;

  	read_lock_irqsave(&hl_irqs_lock, flags);

  	list_for_each_entry(hl, &hl_irqs, irq_list) {

  		if (hl->host_reset)
  			hl->host_reset(host);
  	}

  	read_unlock_irqrestore(&hl_irqs_lock, flags);

  }

  void highlevel_fcp_request(struct hpsb_host *host, int nodeid, int direction,
  			   void *data, size_t length)
  {

  	unsigned long flags;

  	struct hpsb_highlevel *hl;
  	int cts = ((quadlet_t *)data)[0] >> 4;

  	read_lock_irqsave(&hl_irqs_lock, flags);

  	list_for_each_entry(hl, &hl_irqs, irq_list) {

  		if (hl->fcp_request)
  			hl->fcp_request(host, nodeid, direction, cts, data,

  					length);

  	}
  	read_unlock_irqrestore(&hl_irqs_lock, flags);

  }

  /*
   * highlevel_read, highlevel_write, highlevel_lock, highlevel_lock64:
   *
   * These functions are called to handle transactions. They are called when a
   * packet arrives.  The flags argument contains the second word of the first
   * header quadlet of the incoming packet (containing transaction label, retry
   * code, transaction code and priority).  These functions either return a
   * response code or a negative number.  In the first case a response will be
   * generated.  In the latter case, no response will be sent and the driver which
   * handled the request will send the response itself.
   */

  int highlevel_read(struct hpsb_host *host, int nodeid, void *data, u64 addr,
  		   unsigned int length, u16 flags)

  {

  	struct hpsb_address_serve *as;
  	unsigned int partlength;
  	int rcode = RCODE_ADDRESS_ERROR;

  	read_lock(&addr_space_lock);

  	list_for_each_entry(as, &host->addr_space, host_list) {
  		if (as->start > addr)
  			break;

  		if (as->end > addr) {
  			partlength = min(as->end - addr, (u64) length);

  			if (as->op->read)
  				rcode = as->op->read(host, nodeid, data,

  						     addr, partlength, flags);

  			else
  				rcode = RCODE_TYPE_ERROR;

  
  			data += partlength;

  			length -= partlength;
  			addr += partlength;

  			if ((rcode != RCODE_COMPLETE) || !length)
  				break;
  		}
  	}
  	read_unlock(&addr_space_lock);

  	if (length && (rcode == RCODE_COMPLETE))
  		rcode = RCODE_ADDRESS_ERROR;
  	return rcode;

  }

  int highlevel_write(struct hpsb_host *host, int nodeid, int destid, void *data,
  		    u64 addr, unsigned int length, u16 flags)

  {

  	struct hpsb_address_serve *as;
  	unsigned int partlength;
  	int rcode = RCODE_ADDRESS_ERROR;

  	read_lock(&addr_space_lock);

  	list_for_each_entry(as, &host->addr_space, host_list) {
  		if (as->start > addr)
  			break;

  		if (as->end > addr) {
  			partlength = min(as->end - addr, (u64) length);

  			if (as->op->write)
  				rcode = as->op->write(host, nodeid, destid,
  						      data, addr, partlength,
  						      flags);
  			else
  				rcode = RCODE_TYPE_ERROR;

  
  			data += partlength;

  			length -= partlength;
  			addr += partlength;

  			if ((rcode != RCODE_COMPLETE) || !length)
  				break;
  		}
  	}
  	read_unlock(&addr_space_lock);

  	if (length && (rcode == RCODE_COMPLETE))
  		rcode = RCODE_ADDRESS_ERROR;
  	return rcode;

  }

  int highlevel_lock(struct hpsb_host *host, int nodeid, quadlet_t *store,

  		   u64 addr, quadlet_t data, quadlet_t arg, int ext_tcode,
  		   u16 flags)

  {

  	struct hpsb_address_serve *as;
  	int rcode = RCODE_ADDRESS_ERROR;

  	read_lock(&addr_space_lock);

  	list_for_each_entry(as, &host->addr_space, host_list) {
  		if (as->start > addr)
  			break;

  		if (as->end > addr) {
  			if (as->op->lock)
  				rcode = as->op->lock(host, nodeid, store, addr,
  						     data, arg, ext_tcode,
  						     flags);
  			else
  				rcode = RCODE_TYPE_ERROR;
  			break;
  		}
  	}
  	read_unlock(&addr_space_lock);
  	return rcode;

  }
  
  int highlevel_lock64(struct hpsb_host *host, int nodeid, octlet_t *store,

  		     u64 addr, octlet_t data, octlet_t arg, int ext_tcode,
  		     u16 flags)

  {

  	struct hpsb_address_serve *as;
  	int rcode = RCODE_ADDRESS_ERROR;

  	read_lock(&addr_space_lock);

  
  	list_for_each_entry(as, &host->addr_space, host_list) {
  		if (as->start > addr)
  			break;

  		if (as->end > addr) {
  			if (as->op->lock64)
  				rcode = as->op->lock64(host, nodeid, store,
  						       addr, data, arg,
  						       ext_tcode, flags);
  			else
  				rcode = RCODE_TYPE_ERROR;
  			break;
  		}
  	}
  	read_unlock(&addr_space_lock);
  	return rcode;

  }