xref: /netbsd-src/sys/arch/atari/atari/stalloc.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: stalloc.c,v 1.9 2003/07/15 01:19:46 lukem 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/cdefs.h>
37 __KERNEL_RCSID(0, "$NetBSD: stalloc.c,v 1.9 2003/07/15 01:19:46 lukem Exp $");
38 
39 #include <sys/types.h>
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/queue.h>
43 
44 #include <atari/atari/stalloc.h>
45 
46 /*
47  * St-mem allocator.
48  */
49 /*
50  * From atari_init.c
51  */
52 extern u_long st_pool_size, st_pool_virt, st_pool_phys;
53 
54 #define	PHYS_ADDR(virt)	((u_long)(virt) - st_pool_virt + st_pool_phys)
55 
56 static CIRCLEQ_HEAD(stlist, mem_node) st_list;
57 static CIRCLEQ_HEAD(freelist, mem_node) free_list;
58 u_long   stmem_total;		/* total free.		*/
59 
60 void
61 init_stmem()
62 {
63 	int s = splhigh ();
64 	struct mem_node *mem;
65 
66 	stmem_total = st_pool_size - sizeof(*mem);
67 
68 	mem = (struct mem_node *)st_pool_virt;
69 	mem->size = st_pool_size - sizeof(*mem);
70 
71 	CIRCLEQ_INIT(&st_list);
72 	CIRCLEQ_INIT(&free_list);
73 
74 	CIRCLEQ_INSERT_HEAD(&st_list, mem, link);
75 	CIRCLEQ_INSERT_HEAD(&free_list, mem, free_link);
76 	splx(s);
77 }
78 
79 void *
80 alloc_stmem(size, phys_addr)
81 u_long	size;
82 void	**phys_addr;
83 {
84 	struct mem_node *mn, *new, *bfit;
85 	int		s;
86 
87 	if (size == 0)
88 		return NULL;
89 
90 	s = splhigh();
91 
92 	if (size & ~(ST_BLOCKMASK))
93 		size = (size & ST_BLOCKMASK) + ST_BLOCKSIZE;
94 
95 	/*
96 	 * walk list of available nodes, finding the best-fit.
97 	 */
98 	bfit = NULL;
99 	mn   = free_list.cqh_first;
100 	for(; mn != (void *)&free_list; mn = mn->free_link.cqe_next) {
101 		if(size <= mn->size) {
102 			if((bfit != NULL) && (bfit->size < mn->size))
103 				continue;
104 			bfit = mn;
105 		}
106 	}
107 	if(bfit != NULL)
108 		mn = bfit;
109 	if (mn == (void *)&free_list) {
110 		printf("St-mem pool exhausted, binpatch 'st_pool_size'"
111 			"to get more\n");
112 		splx(s);
113 		return(NULL);
114 	}
115 
116 	if ((mn->size - size) <= sizeof (*mn)) {
117 		/*
118 		 * our allocation would not leave room
119 		 * for a new node in between.
120 		 */
121 		CIRCLEQ_REMOVE(&free_list, mn, free_link);
122 		mn->free_link.cqe_next = NULL;
123 		size = mn->size;	 /* increase size. (or same) */
124 		stmem_total -= mn->size;
125 		splx(s);
126 		*phys_addr = (void*)PHYS_ADDR(&mn[1]);
127 		return ((void *)&mn[1]);
128 	}
129 
130 	/*
131 	 * split the node's memory.
132 	 */
133 	new = mn;
134 	new->size -= size + sizeof(struct mem_node);
135 	mn = (struct mem_node *)(MNODES_MEM(new) + new->size);
136 	mn->size = size;
137 
138 	/*
139 	 * add split node to node list
140 	 * and mark as not on free list
141 	 */
142 	CIRCLEQ_INSERT_AFTER(&st_list, new, mn, link);
143 	mn->free_link.cqe_next = NULL;
144 
145 	stmem_total -= size + sizeof(struct mem_node);
146 	splx(s);
147 	*phys_addr = (void*)PHYS_ADDR(&mn[1]);
148 	return ((void *)&mn[1]);
149 }
150 
151 void
152 free_stmem(mem)
153 void *mem;
154 {
155 	struct mem_node *mn, *next, *prev;
156 	int		s;
157 
158 	if (mem == NULL)
159 		return;
160 
161 	s = splhigh();
162 	mn = (struct mem_node *)mem - 1;
163 	next = mn->link.cqe_next;
164 	prev = mn->link.cqe_prev;
165 
166 	/*
167 	 * check ahead of us.
168 	 */
169 	if (next != (void *)&st_list && next->free_link.cqe_next) {
170 		/*
171 		 * if next is: a valid node and a free node. ==> merge
172 		 */
173 		CIRCLEQ_INSERT_BEFORE(&free_list, next, mn, free_link);
174 		CIRCLEQ_REMOVE(&st_list, next, link);
175 		CIRCLEQ_REMOVE(&st_list, next, free_link);
176 		stmem_total += mn->size + sizeof(struct mem_node);
177 		mn->size += next->size + sizeof(struct mem_node);
178 	}
179 	if (prev != (void *)&st_list && prev->free_link.cqe_prev) {
180 		/*
181 		 * if prev is: a valid node and a free node. ==> merge
182 		 */
183 		if (mn->free_link.cqe_next == NULL)
184 			stmem_total += mn->size + sizeof(struct mem_node);
185 		else {
186 			/* already on free list */
187 			CIRCLEQ_REMOVE(&free_list, mn, free_link);
188 			stmem_total += sizeof(struct mem_node);
189 		}
190 		CIRCLEQ_REMOVE(&st_list, mn, link);
191 		prev->size += mn->size + sizeof(struct mem_node);
192 	} else if (mn->free_link.cqe_next == NULL) {
193 		/*
194 		 * we still are not on free list and we need to be.
195 		 * <-- | -->
196 		 */
197 		while (next != (void *)&st_list && prev != (void *)&st_list) {
198 			if (next->free_link.cqe_next) {
199 				CIRCLEQ_INSERT_BEFORE(&free_list, next, mn,
200 				    free_link);
201 				break;
202 			}
203 			if (prev->free_link.cqe_next) {
204 				CIRCLEQ_INSERT_AFTER(&free_list, prev, mn,
205 				    free_link);
206 				break;
207 			}
208 			prev = prev->link.cqe_prev;
209 			next = next->link.cqe_next;
210 		}
211 		if (mn->free_link.cqe_next == NULL) {
212 			if (next == (void *)&st_list) {
213 				/*
214 				 * we are not on list so we can add
215 				 * ourselves to the tail. (we walked to it.)
216 				 */
217 				CIRCLEQ_INSERT_TAIL(&free_list,mn,free_link);
218 			} else {
219 				CIRCLEQ_INSERT_HEAD(&free_list,mn,free_link);
220 			}
221 		}
222 		stmem_total += mn->size;/* add our helpings to the pool. */
223 	}
224 	splx(s);
225 }
226