xref: /netbsd-src/sys/arch/atari/atari/stalloc.c (revision 8b0113cfceadf3ee3bc427c4680b6b46bb57ceea)
1 /*	$NetBSD: stalloc.c,v 1.1.1.1 1995/03/26 07:12:21 leo Exp $	*/
2 
3 /*
4  * Copyright (c) 1995 Leo Weppelman (Atari modifications)
5  * Copyright (c) 1994 Christian E. Hopps (allocator stuff)
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 #include <sys/param.h>
38 #include <sys/queue.h>
39 
40 #include <atari/atari/misc.h>
41 
42 /*
43  * St-mem allocator.
44  */
45 /*
46  * From atari_init.c
47  */
48 extern u_long st_pool_size, st_pool_virt, st_pool_phys;
49 
50 #define	PHYS_ADDR(virt)	((u_long)(virt) - st_pool_virt + st_pool_phys)
51 
52 static CIRCLEQ_HEAD(stlist, mem_node) st_list;
53 static CIRCLEQ_HEAD(freelist, mem_node) free_list;
54 static u_long   stmem_total;		/* total free.		*/
55 
56 void
57 init_stmem()
58 {
59 	int s = splhigh ();
60 	struct mem_node *mem;
61 
62 	stmem_total = st_pool_size - sizeof(*mem);
63 
64 	mem = (struct mem_node *)st_pool_virt;
65 	mem->size = st_pool_size - sizeof(*mem);
66 
67 	CIRCLEQ_INIT(&st_list);
68 	CIRCLEQ_INIT(&free_list);
69 
70 	CIRCLEQ_INSERT_HEAD(&st_list, mem, link);
71 	CIRCLEQ_INSERT_HEAD(&free_list, mem, free_link);
72 	splx(s);
73 }
74 
75 void *
76 alloc_stmem(size, phys_addr)
77 u_long	size;
78 void	**phys_addr;
79 {
80 	struct mem_node *mn, *new;
81 	void		*mem;
82 	int		s;
83 
84 	if (size == 0)
85 		return NULL;
86 
87 	s = splhigh();
88 
89 	if (size & ~(ST_BLOCKMASK))
90 		size = (size & ST_BLOCKMASK) + ST_BLOCKSIZE;
91 
92 	/*
93 	 * walk list of available nodes.
94 	 */
95 	mn = free_list.cqh_first;
96 	while (size > mn->size && mn != (void *)&free_list)
97 		mn = mn->free_link.cqe_next;
98 
99 	if (mn == (void *)&free_list) {
100 		printf("St-mem pool exhausted, binpatch 'st_pool_size'"
101 			"to get more\n");
102 		return(NULL);
103 	}
104 
105 	if ((mn->size - size) <= sizeof (*mn)) {
106 		/*
107 		 * our allocation would not leave room
108 		 * for a new node in between.
109 		 */
110 		CIRCLEQ_REMOVE(&free_list, mn, free_link);
111 		mn->free_link.cqe_next = NULL;
112 		size = mn->size;	 /* increase size. (or same) */
113 		stmem_total -= mn->size;
114 		splx(s);
115 		*phys_addr = (void*)PHYS_ADDR(&mn[1]);
116 		return ((void *)&mn[1]);
117 	}
118 
119 	/*
120 	 * split the node's memory.
121 	 */
122 	new = mn;
123 	new->size -= size + sizeof(struct mem_node);
124 	mn = (struct mem_node *)(MNODES_MEM(new) + new->size);
125 	mn->size = size;
126 
127 	/*
128 	 * add split node to node list
129 	 * and mark as not on free list
130 	 */
131 	CIRCLEQ_INSERT_AFTER(&st_list, new, mn, link);
132 	mn->free_link.cqe_next = NULL;
133 
134 	stmem_total -= size + sizeof(struct mem_node);
135 	splx(s);
136 	*phys_addr = (void*)PHYS_ADDR(&mn[1]);
137 	return ((void *)&mn[1]);
138 }
139 
140 void
141 free_stmem(mem)
142 void *mem;
143 {
144 	struct mem_node *mn, *next, *prev;
145 	int		s;
146 
147 	if (mem == NULL)
148 		return;
149 
150 	s = splhigh();
151 	mn = (struct mem_node *)mem - 1;
152 	next = mn->link.cqe_next;
153 	prev = mn->link.cqe_prev;
154 
155 	/*
156 	 * check ahead of us.
157 	 */
158 	if (next->link.cqe_next != (void *)&st_list &&
159 	    next->free_link.cqe_next) {
160 		/*
161 		 * if next is: a valid node and a free node. ==> merge
162 		 */
163 		CIRCLEQ_INSERT_BEFORE(&free_list, next, mn, free_link);
164 		CIRCLEQ_REMOVE(&st_list, next, link);
165 		CIRCLEQ_REMOVE(&st_list, next, free_link);
166 		stmem_total += mn->size + sizeof(struct mem_node);
167 		mn->size += next->size + sizeof(struct mem_node);
168 	}
169 	if (prev->link.cqe_prev != (void *)&st_list &&
170 	    prev->free_link.cqe_prev) {
171 		/*
172 		 * if prev is: a valid node and a free node. ==> merge
173 		 */
174 		if (mn->free_link.cqe_next == NULL)
175 			stmem_total += mn->size + sizeof(struct mem_node);
176 		else {
177 			/* already on free list */
178 			CIRCLEQ_REMOVE(&free_list, mn, free_link);
179 			stmem_total += sizeof(struct mem_node);
180 		}
181 		CIRCLEQ_REMOVE(&st_list, mn, link);
182 		prev->size += mn->size + sizeof(struct mem_node);
183 	} else if (mn->free_link.cqe_next == NULL) {
184 		/*
185 		 * we still are not on free list and we need to be.
186 		 * <-- | -->
187 		 */
188 		while (next->link.cqe_next != (void *)&st_list &&
189 		    prev->link.cqe_prev != (void *)&st_list) {
190 			if (next->free_link.cqe_next) {
191 				CIRCLEQ_INSERT_BEFORE(&free_list, next, mn,
192 				    free_link);
193 				break;
194 			}
195 			if (prev->free_link.cqe_next) {
196 				CIRCLEQ_INSERT_AFTER(&free_list, prev, mn,
197 				    free_link);
198 				break;
199 			}
200 			prev = prev->link.cqe_prev;
201 			next = next->link.cqe_next;
202 		}
203 		if (mn->free_link.cqe_next == NULL) {
204 			if (next->link.cqe_next == (void *)&st_list) {
205 				/*
206 				 * we are not on list so we can add
207 				 * ourselves to the tail. (we walked to it.)
208 				 */
209 				CIRCLEQ_INSERT_TAIL(&free_list,mn,free_link);
210 			} else {
211 				CIRCLEQ_INSERT_HEAD(&free_list,mn,free_link);
212 			}
213 		}
214 		stmem_total += mn->size;/* add our helpings to the pool. */
215 	}
216 	splx(s);
217 }
218