drivers/staging/lustre/lnet/lnet/lib-me.c - arm/linux - Git at Google

 /*
  * GPL HEADER START
  *
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 only,
  * as published by the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License version 2 for more details (a copy is included
  * in the LICENSE file that accompanied this code).
  *
  * You should have received a copy of the GNU General Public License
  * version 2 along with this program; If not, see
  * http://www.gnu.org/licenses/gpl-2.0.html
  *
  * GPL HEADER END
  */
 /*
  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
  * Use is subject to license terms.
  *
  * Copyright (c) 2012, Intel Corporation.
  */
 /*
  * This file is part of Lustre, http://www.lustre.org/
  * Lustre is a trademark of Sun Microsystems, Inc.
  *
  * lnet/lnet/lib-me.c
  *
  * Match Entry management routines
  */

 #define DEBUG_SUBSYSTEM S_LNET

 #include <linux/lnet/lib-lnet.h>

 /**
  * Create and attach a match entry to the match list of \a portal. The new
  * ME is empty, i.e. not associated with a memory descriptor. LNetMDAttach()
  * can be used to attach a MD to an empty ME.
  *
  * \param portal The portal table index where the ME should be attached.
  * \param match_id Specifies the match criteria for the process ID of
  * the requester. The constants LNET_PID_ANY and LNET_NID_ANY can be
  * used to wildcard either of the identifiers in the lnet_process_id
  * structure.
  * \param match_bits,ignore_bits Specify the match criteria to apply
  * to the match bits in the incoming request. The ignore bits are used
  * to mask out insignificant bits in the incoming match bits. The resulting
  * bits are then compared to the ME's match bits to determine if the
  * incoming request meets the match criteria.
  * \param unlink Indicates whether the ME should be unlinked when the memory
  * descriptor associated with it is unlinked (Note that the check for
  * unlinking a ME only occurs when the memory descriptor is unlinked.).
  * Valid values are LNET_RETAIN and LNET_UNLINK.
  * \param pos Indicates whether the new ME should be prepended or
  * appended to the match list. Allowed constants: LNET_INS_BEFORE,
  * LNET_INS_AFTER.
  * \param handle On successful returns, a handle to the newly created ME
  * object is saved here. This handle can be used later in LNetMEInsert(),
  * LNetMEUnlink(), or LNetMDAttach() functions.
  *
  * \retval 0       On success.
  * \retval -EINVAL If \a portal is invalid.
  * \retval -ENOMEM If new ME object cannot be allocated.
  */
 int
 LNetMEAttach(unsigned int portal,
 	     struct lnet_process_id match_id,
 	     __u64 match_bits, __u64 ignore_bits,
 	     enum lnet_unlink unlink, enum lnet_ins_pos pos,
 	     struct lnet_handle_me *handle)
 {
 	struct lnet_match_table *mtable;
 	struct lnet_me *me;
 	struct list_head *head;

 	LASSERT(the_lnet.ln_refcount > 0);

 	if ((int)portal >= the_lnet.ln_nportals)
 		return -EINVAL;

 	mtable = lnet_mt_of_attach(portal, match_id,
 				   match_bits, ignore_bits, pos);
 	if (!mtable) /* can't match portal type */
 		return -EPERM;

 	me = lnet_me_alloc();
 	if (!me)
 		return -ENOMEM;

 	lnet_res_lock(mtable->mt_cpt);

 	me->me_portal = portal;
 	me->me_match_id = match_id;
 	me->me_match_bits = match_bits;
 	me->me_ignore_bits = ignore_bits;
 	me->me_unlink = unlink;
 	me->me_md = NULL;

 	lnet_res_lh_initialize(the_lnet.ln_me_containers[mtable->mt_cpt],
 			       &me->me_lh);
 	if (ignore_bits)
 		head = &mtable->mt_mhash[LNET_MT_HASH_IGNORE];
 	else
 		head = lnet_mt_match_head(mtable, match_id, match_bits);

 	me->me_pos = head - &mtable->mt_mhash[0];
 	if (pos == LNET_INS_AFTER || pos == LNET_INS_LOCAL)
 		list_add_tail(&me->me_list, head);
 	else
 		list_add(&me->me_list, head);

 	lnet_me2handle(handle, me);

 	lnet_res_unlock(mtable->mt_cpt);
 	return 0;
 }
 EXPORT_SYMBOL(LNetMEAttach);

 /**
  * Create and a match entry and insert it before or after the ME pointed to by
  * \a current_meh. The new ME is empty, i.e. not associated with a memory
  * descriptor. LNetMDAttach() can be used to attach a MD to an empty ME.
  *
  * This function is identical to LNetMEAttach() except for the position
  * where the new ME is inserted.
  *
  * \param current_meh A handle for a ME. The new ME will be inserted
  * immediately before or immediately after this ME.
  * \param match_id,match_bits,ignore_bits,unlink,pos,handle See the discussion
  * for LNetMEAttach().
  *
  * \retval 0       On success.
  * \retval -ENOMEM If new ME object cannot be allocated.
  * \retval -ENOENT If \a current_meh does not point to a valid match entry.
  */
 int
 LNetMEInsert(struct lnet_handle_me current_meh,
 	     struct lnet_process_id match_id,
 	     __u64 match_bits, __u64 ignore_bits,
 	     enum lnet_unlink unlink, enum lnet_ins_pos pos,
 	     struct lnet_handle_me *handle)
 {
 	struct lnet_me *current_me;
 	struct lnet_me *new_me;
 	struct lnet_portal *ptl;
 	int cpt;

 	LASSERT(the_lnet.ln_refcount > 0);

 	if (pos == LNET_INS_LOCAL)
 		return -EPERM;

 	new_me = lnet_me_alloc();
 	if (!new_me)
 		return -ENOMEM;

 	cpt = lnet_cpt_of_cookie(current_meh.cookie);

 	lnet_res_lock(cpt);

 	current_me = lnet_handle2me(&current_meh);
 	if (!current_me) {
 		lnet_me_free(new_me);

 		lnet_res_unlock(cpt);
 		return -ENOENT;
 	}

 	LASSERT(current_me->me_portal < the_lnet.ln_nportals);

 	ptl = the_lnet.ln_portals[current_me->me_portal];
 	if (lnet_ptl_is_unique(ptl)) {
 		/* nosense to insertion on unique portal */
 		lnet_me_free(new_me);
 		lnet_res_unlock(cpt);
 		return -EPERM;
 	}

 	new_me->me_pos = current_me->me_pos;
 	new_me->me_portal = current_me->me_portal;
 	new_me->me_match_id = match_id;
 	new_me->me_match_bits = match_bits;
 	new_me->me_ignore_bits = ignore_bits;
 	new_me->me_unlink = unlink;
 	new_me->me_md = NULL;

 	lnet_res_lh_initialize(the_lnet.ln_me_containers[cpt], &new_me->me_lh);

 	if (pos == LNET_INS_AFTER)
 		list_add(&new_me->me_list, &current_me->me_list);
 	else
 		list_add_tail(&new_me->me_list, &current_me->me_list);

 	lnet_me2handle(handle, new_me);

 	lnet_res_unlock(cpt);

 	return 0;
 }
 EXPORT_SYMBOL(LNetMEInsert);

 /**
  * Unlink a match entry from its match list.
  *
  * This operation also releases any resources associated with the ME. If a
  * memory descriptor is attached to the ME, then it will be unlinked as well
  * and an unlink event will be generated. It is an error to use the ME handle
  * after calling LNetMEUnlink().
  *
  * \param meh A handle for the ME to be unlinked.
  *
  * \retval 0       On success.
  * \retval -ENOENT If \a meh does not point to a valid ME.
  * \see LNetMDUnlink() for the discussion on delivering unlink event.
  */
 int
 LNetMEUnlink(struct lnet_handle_me meh)
 {
 	struct lnet_me *me;
 	struct lnet_libmd *md;
 	struct lnet_event ev;
 	int cpt;

 	LASSERT(the_lnet.ln_refcount > 0);

 	cpt = lnet_cpt_of_cookie(meh.cookie);
 	lnet_res_lock(cpt);

 	me = lnet_handle2me(&meh);
 	if (!me) {
 		lnet_res_unlock(cpt);
 		return -ENOENT;
 	}

 	md = me->me_md;
 	if (md) {
 		md->md_flags |= LNET_MD_FLAG_ABORTED;
 		if (md->md_eq && !md->md_refcount) {
 			lnet_build_unlink_event(md, &ev);
 			lnet_eq_enqueue_event(md->md_eq, &ev);
 		}
 	}

 	lnet_me_unlink(me);

 	lnet_res_unlock(cpt);
 	return 0;
 }
 EXPORT_SYMBOL(LNetMEUnlink);

 /* call with lnet_res_lock please */
 void
 lnet_me_unlink(struct lnet_me *me)
 {
 	list_del(&me->me_list);

 	if (me->me_md) {
 		struct lnet_libmd *md = me->me_md;

 		/* detach MD from portal of this ME */
 		lnet_ptl_detach_md(me, md);
 		lnet_md_unlink(md);
 	}

 	lnet_res_lh_invalidate(&me->me_lh);
 	lnet_me_free(me);
 }
	/*
	* GPL HEADER START
	*
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 only,
	* as published by the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License version 2 for more details (a copy is included
	* in the LICENSE file that accompanied this code).
	*
	* You should have received a copy of the GNU General Public License
	* version 2 along with this program; If not, see
	* http://www.gnu.org/licenses/gpl-2.0.html
	*
	* GPL HEADER END
	*/
	/*
	* Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
	* Use is subject to license terms.
	*
	* Copyright (c) 2012, Intel Corporation.
	*/
	/*
	* This file is part of Lustre, http://www.lustre.org/
	* Lustre is a trademark of Sun Microsystems, Inc.
	*
	* lnet/lnet/lib-me.c
	*
	* Match Entry management routines
	*/

	#define DEBUG_SUBSYSTEM S_LNET

	#include <linux/lnet/lib-lnet.h>

	/**
	* Create and attach a match entry to the match list of \a portal. The new
	* ME is empty, i.e. not associated with a memory descriptor. LNetMDAttach()
	* can be used to attach a MD to an empty ME.
	*
	* \param portal The portal table index where the ME should be attached.
	* \param match_id Specifies the match criteria for the process ID of
	* the requester. The constants LNET_PID_ANY and LNET_NID_ANY can be
	* used to wildcard either of the identifiers in the lnet_process_id
	* structure.
	* \param match_bits,ignore_bits Specify the match criteria to apply
	* to the match bits in the incoming request. The ignore bits are used
	* to mask out insignificant bits in the incoming match bits. The resulting
	* bits are then compared to the ME's match bits to determine if the
	* incoming request meets the match criteria.
	* \param unlink Indicates whether the ME should be unlinked when the memory
	* descriptor associated with it is unlinked (Note that the check for
	* unlinking a ME only occurs when the memory descriptor is unlinked.).
	* Valid values are LNET_RETAIN and LNET_UNLINK.
	* \param pos Indicates whether the new ME should be prepended or
	* appended to the match list. Allowed constants: LNET_INS_BEFORE,
	* LNET_INS_AFTER.
	* \param handle On successful returns, a handle to the newly created ME
	* object is saved here. This handle can be used later in LNetMEInsert(),
	* LNetMEUnlink(), or LNetMDAttach() functions.
	*
	* \retval 0 On success.
	* \retval -EINVAL If \a portal is invalid.
	* \retval -ENOMEM If new ME object cannot be allocated.
	*/
	int
	LNetMEAttach(unsigned int portal,
	struct lnet_process_id match_id,
	__u64 match_bits, __u64 ignore_bits,
	enum lnet_unlink unlink, enum lnet_ins_pos pos,
	struct lnet_handle_me *handle)
	{
	struct lnet_match_table *mtable;
	struct lnet_me *me;
	struct list_head *head;

	LASSERT(the_lnet.ln_refcount > 0);

	if ((int)portal >= the_lnet.ln_nportals)
	return -EINVAL;

	mtable = lnet_mt_of_attach(portal, match_id,
	match_bits, ignore_bits, pos);
	if (!mtable) /* can't match portal type */
	return -EPERM;

	me = lnet_me_alloc();
	if (!me)
	return -ENOMEM;

	lnet_res_lock(mtable->mt_cpt);

	me->me_portal = portal;
	me->me_match_id = match_id;
	me->me_match_bits = match_bits;
	me->me_ignore_bits = ignore_bits;
	me->me_unlink = unlink;
	me->me_md = NULL;

	lnet_res_lh_initialize(the_lnet.ln_me_containers[mtable->mt_cpt],
	&me->me_lh);
	if (ignore_bits)
	head = &mtable->mt_mhash[LNET_MT_HASH_IGNORE];
	else
	head = lnet_mt_match_head(mtable, match_id, match_bits);

	me->me_pos = head - &mtable->mt_mhash[0];
	if (pos == LNET_INS_AFTER \|\| pos == LNET_INS_LOCAL)
	list_add_tail(&me->me_list, head);
	else
	list_add(&me->me_list, head);

	lnet_me2handle(handle, me);

	lnet_res_unlock(mtable->mt_cpt);
	return 0;
	}
	EXPORT_SYMBOL(LNetMEAttach);

	/**
	* Create and a match entry and insert it before or after the ME pointed to by
	* \a current_meh. The new ME is empty, i.e. not associated with a memory
	* descriptor. LNetMDAttach() can be used to attach a MD to an empty ME.
	*
	* This function is identical to LNetMEAttach() except for the position
	* where the new ME is inserted.
	*
	* \param current_meh A handle for a ME. The new ME will be inserted
	* immediately before or immediately after this ME.
	* \param match_id,match_bits,ignore_bits,unlink,pos,handle See the discussion
	* for LNetMEAttach().
	*
	* \retval 0 On success.
	* \retval -ENOMEM If new ME object cannot be allocated.
	* \retval -ENOENT If \a current_meh does not point to a valid match entry.
	*/
	int
	LNetMEInsert(struct lnet_handle_me current_meh,
	struct lnet_process_id match_id,
	__u64 match_bits, __u64 ignore_bits,
	enum lnet_unlink unlink, enum lnet_ins_pos pos,
	struct lnet_handle_me *handle)
	{
	struct lnet_me *current_me;
	struct lnet_me *new_me;
	struct lnet_portal *ptl;
	int cpt;

	LASSERT(the_lnet.ln_refcount > 0);

	if (pos == LNET_INS_LOCAL)
	return -EPERM;

	new_me = lnet_me_alloc();
	if (!new_me)
	return -ENOMEM;

	cpt = lnet_cpt_of_cookie(current_meh.cookie);

	lnet_res_lock(cpt);

	current_me = lnet_handle2me(&current_meh);
	if (!current_me) {
	lnet_me_free(new_me);

	lnet_res_unlock(cpt);
	return -ENOENT;
	}

	LASSERT(current_me->me_portal < the_lnet.ln_nportals);

	ptl = the_lnet.ln_portals[current_me->me_portal];
	if (lnet_ptl_is_unique(ptl)) {
	/* nosense to insertion on unique portal */
	lnet_me_free(new_me);
	lnet_res_unlock(cpt);
	return -EPERM;
	}

	new_me->me_pos = current_me->me_pos;
	new_me->me_portal = current_me->me_portal;
	new_me->me_match_id = match_id;
	new_me->me_match_bits = match_bits;
	new_me->me_ignore_bits = ignore_bits;
	new_me->me_unlink = unlink;
	new_me->me_md = NULL;

	lnet_res_lh_initialize(the_lnet.ln_me_containers[cpt], &new_me->me_lh);

	if (pos == LNET_INS_AFTER)
	list_add(&new_me->me_list, &current_me->me_list);
	else
	list_add_tail(&new_me->me_list, &current_me->me_list);

	lnet_me2handle(handle, new_me);

	lnet_res_unlock(cpt);

	return 0;
	}
	EXPORT_SYMBOL(LNetMEInsert);

	/**
	* Unlink a match entry from its match list.
	*
	* This operation also releases any resources associated with the ME. If a
	* memory descriptor is attached to the ME, then it will be unlinked as well
	* and an unlink event will be generated. It is an error to use the ME handle
	* after calling LNetMEUnlink().
	*
	* \param meh A handle for the ME to be unlinked.
	*
	* \retval 0 On success.
	* \retval -ENOENT If \a meh does not point to a valid ME.
	* \see LNetMDUnlink() for the discussion on delivering unlink event.
	*/
	int
	LNetMEUnlink(struct lnet_handle_me meh)
	{
	struct lnet_me *me;
	struct lnet_libmd *md;
	struct lnet_event ev;
	int cpt;

	LASSERT(the_lnet.ln_refcount > 0);

	cpt = lnet_cpt_of_cookie(meh.cookie);
	lnet_res_lock(cpt);

	me = lnet_handle2me(&meh);
	if (!me) {
	lnet_res_unlock(cpt);
	return -ENOENT;
	}

	md = me->me_md;
	if (md) {
	md->md_flags \|= LNET_MD_FLAG_ABORTED;
	if (md->md_eq && !md->md_refcount) {
	lnet_build_unlink_event(md, &ev);
	lnet_eq_enqueue_event(md->md_eq, &ev);
	}
	}

	lnet_me_unlink(me);

	lnet_res_unlock(cpt);
	return 0;
	}
	EXPORT_SYMBOL(LNetMEUnlink);

	/* call with lnet_res_lock please */
	void
	lnet_me_unlink(struct lnet_me *me)
	{
	list_del(&me->me_list);

	if (me->me_md) {
	struct lnet_libmd *md = me->me_md;

	/* detach MD from portal of this ME */
	lnet_ptl_detach_md(me, md);
	lnet_md_unlink(md);
	}

	lnet_res_lh_invalidate(&me->me_lh);
	lnet_me_free(me);
	}