xref: /illumos-gate/usr/src/uts/common/ipp/ipgpc/ba_table.c (revision 16b76d3cb933ff92018a2a75594449010192eacb)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2002-2003 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/errno.h>
28 #include <ipp/ipgpc/classifier.h>
29 
30 /* Implementation file for behavior aggregate (BA) lookup table */
31 
32 /*
33  * ba_insert(bataid, filter_id, val, mask)
34  *
35  * inserts filter_id into element list of bataid->table->masked_values
36  * at position val& mask, mask is inserted into the mask list.
37  * filter_id shouldn't already exist in element list at
38  * bataid->table->masked_values[val], an error message is printed if this
39  * occurs.
40  * return DONTCARE_VALUE if mask == 0, NORMAL_VALUE otherwise
41  */
42 int
43 ba_insert(ba_table_id_t *bataid, int filter_id, uint8_t val, uint8_t mask)
44 {
45 	uint8_t mskd_val = val & mask;
46 	ba_table_t *table = &bataid->table;
47 
48 	/* dontcares are not inserted */
49 	if (mask == 0) {
50 		++bataid->stats.num_dontcare;
51 		return (DONTCARE_VALUE);
52 	}
53 
54 	if (bataid->info.dontcareonly == B_TRUE) {
55 		bataid->info.dontcareonly = B_FALSE;
56 	}
57 
58 	if (ipgpc_list_insert(&table->masked_values[mskd_val].filter_list,
59 	    filter_id) == EEXIST) {
60 		ipgpc0dbg(("ba_insert():filter_id %d EEXIST in ba_table",
61 		    filter_id));
62 	} else {
63 		/* insert mask */
64 		(void) ipgpc_list_insert(&table->masks, mask);
65 		/* update stats */
66 		++table->masked_values[mskd_val].info;
67 		++bataid->stats.num_inserted;
68 	}
69 	return (NORMAL_VALUE);
70 }
71 
72 /*
73  * ba_retrieve(bataid, value, fid_table)
74  *
75  * searches for all filters matching value in bataid->table
76  * search is performed by appling each mask in bataid->table->masks list
77  * to value and then looking value up in bataid->table->masked_values.
78  * Each filter id that is matched, is inserted into fid_table
79  * returns number of matched filters or (-1) if memory error
80  */
81 int
82 ba_retrieve(ba_table_id_t *bataid, uint8_t value, ht_match_t *fid_table)
83 {
84 	element_node_t *p;
85 	element_node_t *filter_list;
86 	int num_found = 0;
87 	int ret;
88 	int masked_value = 0;
89 	ba_table_t *table = &bataid->table;
90 
91 	/* special case, if value == 0, no need to apply masks */
92 	if (value == 0) {
93 		/* masked value will always be 0 for this case */
94 		filter_list =
95 		    table->masked_values[0].filter_list;
96 		if ((num_found = ipgpc_mark_found(bataid->info.mask,
97 		    filter_list, fid_table)) == -1) {
98 			return (-1); /* signifies a memory error */
99 		}
100 		return (num_found);
101 	}
102 
103 	/* apply each mask to the value and do the look up in the ba table */
104 	for (p = table->masks; p != NULL; p = p->next) {
105 		masked_value = (uint8_t)(p->id) & value;
106 		if (bataid->table.masked_values[masked_value].info == 0) {
107 			/* masked_value has 0 filters associated with it */
108 			continue;
109 		}
110 		filter_list =
111 		    table->masked_values[masked_value].filter_list;
112 		if ((ret = ipgpc_mark_found(bataid->info.mask, filter_list,
113 		    fid_table)) == -1) {
114 			return (-1); /* signifies a memory error */
115 		}
116 		num_found += ret; /* increment num_found */
117 	}
118 
119 	return (num_found);
120 }
121 
122 /*
123  * ba_remove(bataid, filter_id, value, mask)
124  *
125  * removes filter_id from bataid->table->masked_values[mask & value]
126  * mask is removed from bataid->table->masks if refcnt == 0 for that list
127  */
128 void
129 ba_remove(ba_table_id_t *bataid, int filter_id, uint8_t value, uint8_t mask)
130 {
131 	uint8_t masked_value = value & mask;
132 	ba_table_t *table = &bataid->table;
133 
134 	/* dontcares are not inserted */
135 	if (mask == 0) {
136 		--bataid->stats.num_dontcare;
137 		return;
138 	}
139 
140 	if (ipgpc_list_remove(&table->masked_values[masked_value].filter_list,
141 	    filter_id) == B_TRUE) {
142 		/* update stats */
143 		--table->masked_values[masked_value].info;
144 		--bataid->stats.num_inserted;
145 		/*
146 		 * check to see if removing this entry will result in
147 		 * don't cares only inserted in the table
148 		 */
149 		if (bataid->stats.num_inserted <= 0) {
150 			bataid->info.dontcareonly = B_TRUE;
151 		}
152 		/* remove mask if refcnt == 0 */
153 		(void) ipgpc_list_remove(&table->masks, mask);
154 	}
155 }
156