WebSVN – HelenOS – Diff – /trunk/uspace/srv/vfs/vfs_node.c


/*
 * Copyright (c) 2008 Jakub Jermar
 * All rights reserved.
 *
 * 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 name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup fs
 * @{
 */
 
/**
 * @file    vfs_node.c
 * @brief   Various operations on VFS nodes have their home in this file.
 */
 
#include "vfs.h"
#include <stdlib.h>
#include <string.h>
#include <fibril_sync.h>
#include <adt/hash_table.h>
#include <assert.h>
#include <async.h>
#include <errno.h>
 
/** Mutex protecting the VFS node hash table. */
FIBRIL_MUTEX_INITIALIZE(nodes_mutex);
 
#define NODES_BUCKETS_LOG   8
#define NODES_BUCKETS       (1 << NODES_BUCKETS_LOG)
 
/** VFS node hash table containing all active, in-memory VFS nodes. */
hash_table_t nodes;
 
#define KEY_FS_HANDLE   0
#define KEY_DEV_HANDLE  1
#define KEY_INDEX   2
 
static hash_index_t nodes_hash(unsigned long []);
static int nodes_compare(unsigned long [], hash_count_t, link_t *);
static void nodes_remove_callback(link_t *);
 
/** VFS node hash table operations. */
hash_table_operations_t nodes_ops = {
    .hash = nodes_hash,
    .compare = nodes_compare,
    .remove_callback = nodes_remove_callback
};
 
/** Initialize the VFS node hash table.
 *
 * @return      Return true on success, false on failure.
 */
bool vfs_nodes_init(void)
{
    return hash_table_create(&nodes, NODES_BUCKETS, 3, &nodes_ops);
}
 
static inline void _vfs_node_addref(vfs_node_t *node)
{
    node->refcnt++;
}
 
/** Increment reference count of a VFS node.
 *
 * @param node      VFS node that will have its refcnt incremented.
 */
void vfs_node_addref(vfs_node_t *node)
{
    fibril_mutex_lock(&nodes_mutex);
    _vfs_node_addref(node);
    fibril_mutex_unlock(&nodes_mutex);
}
 
/** Decrement reference count of a VFS node.
 *
 * This function handles the case when the reference count drops to zero.
 *
 * @param node      VFS node that will have its refcnt decremented.
 */
void vfs_node_delref(vfs_node_t *node)
{
    bool free_vfs_node = false;
    bool free_fs_node = false;
 
    fibril_mutex_lock(&nodes_mutex);
    if (node->refcnt-- == 1) {
        /*
         * We are dropping the last reference to this node.
         * Remove it from the VFS node hash table.
         */
        unsigned long key[] = {
            [KEY_FS_HANDLE] = node->fs_handle,
            [KEY_DEV_HANDLE] = node->dev_handle,
            [KEY_INDEX] = node->index
        };
        hash_table_remove(&nodes, key, 3);
        free_vfs_node = true;
        if (!node->lnkcnt)
            free_fs_node = true;
    }
    fibril_mutex_unlock(&nodes_mutex);
 
    if (free_fs_node) {
        /*
         * The node is not visible in the file system namespace.
         * Free up its resources.
         */
        int phone = vfs_grab_phone(node->fs_handle);
        ipcarg_t rc;
        rc = async_req_2_0(phone, VFS_OUT_DESTROY,
            (ipcarg_t)node->dev_handle, (ipcarg_t)node->index);
        assert(rc == EOK);
        vfs_release_phone(phone);
    }
    if (free_vfs_node)
        free(node);
}
 
/** Find VFS node.
 *
 * This function will try to lookup the given triplet in the VFS node hash
 * table. In case the triplet is not found there, a new VFS node is created.
 * In any case, the VFS node will have its reference count incremented. Every
 * node returned by this call should be eventually put back by calling
 * vfs_node_put() on it.
 *
 * @param result    Populated lookup result structure.
 *
 * @return      VFS node corresponding to the given triplet.
 */
vfs_node_t *vfs_node_get(vfs_lookup_res_t *result)
{
    unsigned long key[] = {
        [KEY_FS_HANDLE] = result->triplet.fs_handle,
        [KEY_DEV_HANDLE] = result->triplet.dev_handle,
        [KEY_INDEX] = result->triplet.index
    };
    link_t *tmp;
    vfs_node_t *node;
 
    fibril_mutex_lock(&nodes_mutex);
    tmp = hash_table_find(&nodes, key);
    if (!tmp) {
        node = (vfs_node_t *) malloc(sizeof(vfs_node_t));
        if (!node) {
            fibril_mutex_unlock(&nodes_mutex);
            return NULL;
        }
        memset(node, 0, sizeof(vfs_node_t));
        node->fs_handle = result->triplet.fs_handle;
        node->dev_handle = result->triplet.dev_handle;
        node->index = result->triplet.index;
        node->size = result->size;
        node->lnkcnt = result->lnkcnt;
        node->type = result->type;
        link_initialize(&node->nh_link);
        fibril_rwlock_initialize(&node->contents_rwlock);
        hash_table_insert(&nodes, key, &node->nh_link);
    } else {
        node = hash_table_get_instance(tmp, vfs_node_t, nh_link);
        if (node->type == VFS_NODE_UNKNOWN &&
            result->type != VFS_NODE_UNKNOWN) {
            /* Upgrade the node type. */
            node->type = result->type;
        }
    }
 
    assert(node->size == result->size);
    assert(node->lnkcnt == result->lnkcnt);
    assert(node->type == result->type || result->type == VFS_NODE_UNKNOWN);
 
    _vfs_node_addref(node);
    fibril_mutex_unlock(&nodes_mutex);
 
    return node;
}
 
/** Return VFS node when no longer needed by the caller.
 *
 * This function will remove the reference on the VFS node created by
 * vfs_node_get(). This function can only be called as a closing bracket to the
 * preceding vfs_node_get() call.
 *
 * @param node      VFS node being released.
 */
void vfs_node_put(vfs_node_t *node)
{
    vfs_node_delref(node);
}
 
hash_index_t nodes_hash(unsigned long key[])
{
    hash_index_t a = key[KEY_FS_HANDLE] << (NODES_BUCKETS_LOG / 4);
    hash_index_t b = (a | key[KEY_DEV_HANDLE]) << (NODES_BUCKETS_LOG / 2);
   
    return (b | key[KEY_INDEX]) & (NODES_BUCKETS - 1);
}
 
int nodes_compare(unsigned long key[], hash_count_t keys, link_t *item)
{
    vfs_node_t *node = hash_table_get_instance(item, vfs_node_t, nh_link);
    return (node->fs_handle == key[KEY_FS_HANDLE]) &&
        (node->dev_handle == key[KEY_DEV_HANDLE]) &&
        (node->index == key[KEY_INDEX]);
}
 
void nodes_remove_callback(link_t *item)
{
}
 
/**
 * @}
 */
 

Subversion Repositories HelenOS

(root)/trunk/uspace/srv/vfs/vfs_node.c @ 3536 – Rev 4555 → 4584

Rev 4555		Rev 4584
1	/*	1	/*
2	* Copyright (c) 2008 Jakub Jermar	2	* Copyright (c) 2008 Jakub Jermar
3	* All rights reserved.	3	* All rights reserved.
4	*	4	*
5	* Redistribution and use in source and binary forms, with or without	5	* Redistribution and use in source and binary forms, with or without
6	* modification, are permitted provided that the following conditions	6	* modification, are permitted provided that the following conditions
7	* are met:	7	* are met:
8	*	8	*
9	* - Redistributions of source code must retain the above copyright	9	* - Redistributions of source code must retain the above copyright
10	* notice, this list of conditions and the following disclaimer.	10	* notice, this list of conditions and the following disclaimer.
11	* - Redistributions in binary form must reproduce the above copyright	11	* - Redistributions in binary form must reproduce the above copyright
12	* notice, this list of conditions and the following disclaimer in the	12	* notice, this list of conditions and the following disclaimer in the
13	* documentation and/or other materials provided with the distribution.	13	* documentation and/or other materials provided with the distribution.
14	* - The name of the author may not be used to endorse or promote products	14	* - The name of the author may not be used to endorse or promote products
15	* derived from this software without specific prior written permission.	15	* derived from this software without specific prior written permission.
16	*	16	*
17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	17	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	18	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	19	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	20	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	21	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	22	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	23	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	24	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	25	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	26	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27	*/	27	*/
28		28
29	/** @addtogroup fs	29	/** @addtogroup fs
30	* @{	30	* @{
31	*/	31	*/
32		32
33	/**	33	/**
34	* @file vfs_node.c	34	* @file vfs_node.c
35	* @brief Various operations on VFS nodes have their home in this file.	35	* @brief Various operations on VFS nodes have their home in this file.
36	*/	36	*/
37		37
38	#include "vfs.h"	38	#include "vfs.h"
39	#include <stdlib.h>	39	#include <stdlib.h>
40	#include <string.h>	40	#include <string.h>
41	#include <fibril_sync.h>	41	#include <fibril_sync.h>
42	#include <adt/hash_table.h>	42	#include <adt/hash_table.h>
43	#include <assert.h>	43	#include <assert.h>
44	#include <async.h>	44	#include <async.h>
45	#include <errno.h>	45	#include <errno.h>
46		46
47	/** Mutex protecting the VFS node hash table. */	47	/** Mutex protecting the VFS node hash table. */
48	FIBRIL_MUTEX_INITIALIZE(nodes_mutex);	48	FIBRIL_MUTEX_INITIALIZE(nodes_mutex);
49		49
50	#define NODES_BUCKETS_LOG 8	50	#define NODES_BUCKETS_LOG 8
51	#define NODES_BUCKETS (1 << NODES_BUCKETS_LOG)	51	#define NODES_BUCKETS (1 << NODES_BUCKETS_LOG)
52		52
53	/** VFS node hash table containing all active, in-memory VFS nodes. */	53	/** VFS node hash table containing all active, in-memory VFS nodes. */
54	hash_table_t nodes;	54	hash_table_t nodes;
55		55
56	#define KEY_FS_HANDLE 0	56	#define KEY_FS_HANDLE 0
57	#define KEY_DEV_HANDLE 1	57	#define KEY_DEV_HANDLE 1
58	#define KEY_INDEX 2	58	#define KEY_INDEX 2
59		59
60	static hash_index_t nodes_hash(unsigned long []);	60	static hash_index_t nodes_hash(unsigned long []);
61	static int nodes_compare(unsigned long [], hash_count_t, link_t *);	61	static int nodes_compare(unsigned long [], hash_count_t, link_t *);
62	static void nodes_remove_callback(link_t *);	62	static void nodes_remove_callback(link_t *);
63		63
64	/** VFS node hash table operations. */	64	/** VFS node hash table operations. */
65	hash_table_operations_t nodes_ops = {	65	hash_table_operations_t nodes_ops = {
66	.hash = nodes_hash,	66	.hash = nodes_hash,
67	.compare = nodes_compare,	67	.compare = nodes_compare,
68	.remove_callback = nodes_remove_callback	68	.remove_callback = nodes_remove_callback
69	};	69	};
70		70
71	/** Initialize the VFS node hash table.	71	/** Initialize the VFS node hash table.
72	*	72	*
73	* @return Return true on success, false on failure.	73	* @return Return true on success, false on failure.
74	*/	74	*/
75	bool vfs_nodes_init(void)	75	bool vfs_nodes_init(void)
76	{	76	{
77	return hash_table_create(&nodes, NODES_BUCKETS, 3, &nodes_ops);	77	return hash_table_create(&nodes, NODES_BUCKETS, 3, &nodes_ops);
78	}	78	}
79		79
80	static inline void _vfs_node_addref(vfs_node_t *node)	80	static inline void _vfs_node_addref(vfs_node_t *node)
81	{	81	{
82	node->refcnt++;	82	node->refcnt++;
83	}	83	}
84		84
85	/** Increment reference count of a VFS node.	85	/** Increment reference count of a VFS node.
86	*	86	*
87	* @param node VFS node that will have its refcnt incremented.	87	* @param node VFS node that will have its refcnt incremented.
88	*/	88	*/
89	void vfs_node_addref(vfs_node_t *node)	89	void vfs_node_addref(vfs_node_t *node)
90	{	90	{
91	fibril_mutex_lock(&nodes_mutex);	91	fibril_mutex_lock(&nodes_mutex);
92	_vfs_node_addref(node);	92	_vfs_node_addref(node);
93	fibril_mutex_unlock(&nodes_mutex);	93	fibril_mutex_unlock(&nodes_mutex);
94	}	94	}
95		95
96	/** Decrement reference count of a VFS node.	96	/** Decrement reference count of a VFS node.
97	*	97	*
98	* This function handles the case when the reference count drops to zero.	98	* This function handles the case when the reference count drops to zero.
99	*	99	*
100	* @param node VFS node that will have its refcnt decremented.	100	* @param node VFS node that will have its refcnt decremented.
101	*/	101	*/
102	void vfs_node_delref(vfs_node_t *node)	102	void vfs_node_delref(vfs_node_t *node)
103	{	103	{
104	bool free_vfs_node = false;	104	bool free_vfs_node = false;
105	bool free_fs_node = false;	105	bool free_fs_node = false;
106		106
107	fibril_mutex_lock(&nodes_mutex);	107	fibril_mutex_lock(&nodes_mutex);
108	if (node->refcnt-- == 1) {	108	if (node->refcnt-- == 1) {
109	/*	109	/*
110	* We are dropping the last reference to this node.	110	* We are dropping the last reference to this node.
111	* Remove it from the VFS node hash table.	111	* Remove it from the VFS node hash table.
112	*/	112	*/
113	unsigned long key[] = {	113	unsigned long key[] = {
114	[KEY_FS_HANDLE] = node->fs_handle,	114	[KEY_FS_HANDLE] = node->fs_handle,
115	[KEY_DEV_HANDLE] = node->dev_handle,	115	[KEY_DEV_HANDLE] = node->dev_handle,
116	[KEY_INDEX] = node->index	116	[KEY_INDEX] = node->index
117	};	117	};
118	hash_table_remove(&nodes, key, 3);	118	hash_table_remove(&nodes, key, 3);
119	free_vfs_node = true;	119	free_vfs_node = true;
120	if (!node->lnkcnt)	120	if (!node->lnkcnt)
121	free_fs_node = true;	121	free_fs_node = true;
122	}	122	}
123	fibril_mutex_unlock(&nodes_mutex);	123	fibril_mutex_unlock(&nodes_mutex);
124		124
125	if (free_fs_node) {	125	if (free_fs_node) {
126	/*	126	/*
127	* The node is not visible in the file system namespace.	127	* The node is not visible in the file system namespace.
128	* Free up its resources.	128	* Free up its resources.
129	*/	129	*/
130	int phone = vfs_grab_phone(node->fs_handle);	130	int phone = vfs_grab_phone(node->fs_handle);
131	ipcarg_t rc;	131	ipcarg_t rc;
132	rc = async_req_2_0(phone, VFS_DESTROY,	132	rc = async_req_2_0(phone, VFS_OUT_DESTROY,
133	(ipcarg_t)node->dev_handle, (ipcarg_t)node->index);	133	(ipcarg_t)node->dev_handle, (ipcarg_t)node->index);
134	assert(rc == EOK);	134	assert(rc == EOK);
135	vfs_release_phone(phone);	135	vfs_release_phone(phone);
136	}	136	}
137	if (free_vfs_node)	137	if (free_vfs_node)
138	free(node);	138	free(node);
139	}	139	}
140		140
141	/** Find VFS node.	141	/** Find VFS node.
142	*	142	*
143	* This function will try to lookup the given triplet in the VFS node hash	143	* This function will try to lookup the given triplet in the VFS node hash
144	* table. In case the triplet is not found there, a new VFS node is created.	144	* table. In case the triplet is not found there, a new VFS node is created.
145	* In any case, the VFS node will have its reference count incremented. Every	145	* In any case, the VFS node will have its reference count incremented. Every
146	* node returned by this call should be eventually put back by calling	146	* node returned by this call should be eventually put back by calling
147	* vfs_node_put() on it.	147	* vfs_node_put() on it.
148	*	148	*
149	* @param result Populated lookup result structure.	149	* @param result Populated lookup result structure.
150	*	150	*
151	* @return VFS node corresponding to the given triplet.	151	* @return VFS node corresponding to the given triplet.
152	*/	152	*/
153	vfs_node_t vfs_node_get(vfs_lookup_res_t result)	153	vfs_node_t vfs_node_get(vfs_lookup_res_t result)
154	{	154	{
155	unsigned long key[] = {	155	unsigned long key[] = {
156	[KEY_FS_HANDLE] = result->triplet.fs_handle,	156	[KEY_FS_HANDLE] = result->triplet.fs_handle,
157	[KEY_DEV_HANDLE] = result->triplet.dev_handle,	157	[KEY_DEV_HANDLE] = result->triplet.dev_handle,
158	[KEY_INDEX] = result->triplet.index	158	[KEY_INDEX] = result->triplet.index
159	};	159	};
160	link_t *tmp;	160	link_t *tmp;
161	vfs_node_t *node;	161	vfs_node_t *node;
162		162
163	fibril_mutex_lock(&nodes_mutex);	163	fibril_mutex_lock(&nodes_mutex);
164	tmp = hash_table_find(&nodes, key);	164	tmp = hash_table_find(&nodes, key);
165	if (!tmp) {	165	if (!tmp) {
166	node = (vfs_node_t *) malloc(sizeof(vfs_node_t));	166	node = (vfs_node_t *) malloc(sizeof(vfs_node_t));
167	if (!node) {	167	if (!node) {
168	fibril_mutex_unlock(&nodes_mutex);	168	fibril_mutex_unlock(&nodes_mutex);
169	return NULL;	169	return NULL;
170	}	170	}
171	memset(node, 0, sizeof(vfs_node_t));	171	memset(node, 0, sizeof(vfs_node_t));
172	node->fs_handle = result->triplet.fs_handle;	172	node->fs_handle = result->triplet.fs_handle;
173	node->dev_handle = result->triplet.dev_handle;	173	node->dev_handle = result->triplet.dev_handle;
174	node->index = result->triplet.index;	174	node->index = result->triplet.index;
175	node->size = result->size;	175	node->size = result->size;
176	node->lnkcnt = result->lnkcnt;	176	node->lnkcnt = result->lnkcnt;
177	node->type = result->type;	177	node->type = result->type;
178	link_initialize(&node->nh_link);	178	link_initialize(&node->nh_link);
179	fibril_rwlock_initialize(&node->contents_rwlock);	179	fibril_rwlock_initialize(&node->contents_rwlock);
180	hash_table_insert(&nodes, key, &node->nh_link);	180	hash_table_insert(&nodes, key, &node->nh_link);
181	} else {	181	} else {
182	node = hash_table_get_instance(tmp, vfs_node_t, nh_link);	182	node = hash_table_get_instance(tmp, vfs_node_t, nh_link);
183	if (node->type == VFS_NODE_UNKNOWN &&	183	if (node->type == VFS_NODE_UNKNOWN &&
184	result->type != VFS_NODE_UNKNOWN) {	184	result->type != VFS_NODE_UNKNOWN) {
185	/* Upgrade the node type. */	185	/* Upgrade the node type. */
186	node->type = result->type;	186	node->type = result->type;
187	}	187	}
188	}	188	}
189		189
190	assert(node->size == result->size);	190	assert(node->size == result->size);
191	assert(node->lnkcnt == result->lnkcnt);	191	assert(node->lnkcnt == result->lnkcnt);
192	assert(node->type == result->type \|\| result->type == VFS_NODE_UNKNOWN);	192	assert(node->type == result->type \|\| result->type == VFS_NODE_UNKNOWN);
193		193
194	_vfs_node_addref(node);	194	_vfs_node_addref(node);
195	fibril_mutex_unlock(&nodes_mutex);	195	fibril_mutex_unlock(&nodes_mutex);
196		196
197	return node;	197	return node;
198	}	198	}
199		199
200	/** Return VFS node when no longer needed by the caller.	200	/** Return VFS node when no longer needed by the caller.
201	*	201	*
202	* This function will remove the reference on the VFS node created by	202	* This function will remove the reference on the VFS node created by
203	* vfs_node_get(). This function can only be called as a closing bracket to the	203	* vfs_node_get(). This function can only be called as a closing bracket to the
204	* preceding vfs_node_get() call.	204	* preceding vfs_node_get() call.
205	*	205	*
206	* @param node VFS node being released.	206	* @param node VFS node being released.
207	*/	207	*/
208	void vfs_node_put(vfs_node_t *node)	208	void vfs_node_put(vfs_node_t *node)
209	{	209	{
210	vfs_node_delref(node);	210	vfs_node_delref(node);
211	}	211	}
212		212
213	hash_index_t nodes_hash(unsigned long key[])	213	hash_index_t nodes_hash(unsigned long key[])
214	{	214	{
215	hash_index_t a = key[KEY_FS_HANDLE] << (NODES_BUCKETS_LOG / 4);	215	hash_index_t a = key[KEY_FS_HANDLE] << (NODES_BUCKETS_LOG / 4);
216	hash_index_t b = (a \| key[KEY_DEV_HANDLE]) << (NODES_BUCKETS_LOG / 2);	216	hash_index_t b = (a \| key[KEY_DEV_HANDLE]) << (NODES_BUCKETS_LOG / 2);
217		217
218	return (b \| key[KEY_INDEX]) & (NODES_BUCKETS - 1);	218	return (b \| key[KEY_INDEX]) & (NODES_BUCKETS - 1);
219	}	219	}
220		220
221	int nodes_compare(unsigned long key[], hash_count_t keys, link_t *item)	221	int nodes_compare(unsigned long key[], hash_count_t keys, link_t *item)
222	{	222	{
223	vfs_node_t *node = hash_table_get_instance(item, vfs_node_t, nh_link);	223	vfs_node_t *node = hash_table_get_instance(item, vfs_node_t, nh_link);
224	return (node->fs_handle == key[KEY_FS_HANDLE]) &&	224	return (node->fs_handle == key[KEY_FS_HANDLE]) &&
225	(node->dev_handle == key[KEY_DEV_HANDLE]) &&	225	(node->dev_handle == key[KEY_DEV_HANDLE]) &&
226	(node->index == key[KEY_INDEX]);	226	(node->index == key[KEY_INDEX]);
227	}	227	}
228		228
229	void nodes_remove_callback(link_t *item)	229	void nodes_remove_callback(link_t *item)
230	{	230	{
231	}	231	}
232		232
233	/**	233	/**
234	* @}	234	* @}
235	*/	235	*/
236		236