1 /* $NetBSD: stalloc.c,v 1.16 2014/01/03 07:14:20 mlelstv 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 1.16 2014/01/03 07:14:20 mlelstv 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 TAILQ_HEAD(stlist, mem_node) st_list; 57 static TAILQ_HEAD(freelist, mem_node) free_list; 58 u_long stmem_total; /* total free. */ 59 60 void 61 init_stmem(void) 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 TAILQ_INIT(&st_list); 72 TAILQ_INIT(&free_list); 73 74 TAILQ_INSERT_HEAD(&st_list, mem, link); 75 TAILQ_INSERT_HEAD(&free_list, mem, free_link); 76 splx(s); 77 } 78 79 void * 80 alloc_stmem(u_long size, void **phys_addr) 81 { 82 struct mem_node *mn, *new, *bfit; 83 int s; 84 85 if (size == 0) 86 return NULL; 87 88 s = splhigh(); 89 90 if (size & ~(ST_BLOCKMASK)) 91 size = (size & ST_BLOCKMASK) + ST_BLOCKSIZE; 92 93 /* 94 * walk list of available nodes, finding the best-fit. 95 */ 96 bfit = NULL; 97 TAILQ_FOREACH(mn, &free_list, free_link) { 98 if (size <= mn->size) { 99 if ((bfit != NULL) && 100 (bfit->size < mn->size)) 101 continue; 102 bfit = mn; 103 } 104 } 105 if (bfit != NULL) 106 mn = bfit; 107 if (mn == NULL) { 108 printf("St-mem pool exhausted, binpatch 'st_pool_size'" 109 "to get more\n"); 110 splx(s); 111 return NULL; 112 } 113 114 if ((mn->size - size) <= sizeof (*mn)) { 115 /* 116 * our allocation would not leave room 117 * for a new node in between. 118 */ 119 TAILQ_REMOVE(&free_list, mn, free_link); 120 mn->type = MNODE_USED; 121 size = mn->size; /* increase size. (or same) */ 122 stmem_total -= mn->size; 123 splx(s); 124 *phys_addr = (void*)PHYS_ADDR(&mn[1]); 125 return ((void *)&mn[1]); 126 } 127 128 /* 129 * split the node's memory. 130 */ 131 new = mn; 132 new->size -= size + sizeof(struct mem_node); 133 mn = (struct mem_node *)(MNODES_MEM(new) + new->size); 134 mn->size = size; 135 136 /* 137 * add split node to node list 138 * and mark as not on free list 139 */ 140 TAILQ_INSERT_AFTER(&st_list, new, mn, link); 141 mn->type = MNODE_USED; 142 143 stmem_total -= size + sizeof(struct mem_node); 144 splx(s); 145 *phys_addr = (void*)PHYS_ADDR(&mn[1]); 146 return ((void *)&mn[1]); 147 } 148 149 void 150 free_stmem(void *mem) 151 { 152 struct mem_node *mn, *next, *prev; 153 int s; 154 155 if (mem == NULL) 156 return; 157 158 s = splhigh(); 159 mn = (struct mem_node *)mem - 1; 160 next = TAILQ_NEXT(mn, link); 161 prev = TAILQ_PREV(mn, stlist, link); 162 163 /* 164 * check ahead of us. 165 */ 166 if (next->type == MNODE_FREE) { 167 /* 168 * if next is: a valid node and a free node. ==> merge 169 */ 170 TAILQ_INSERT_BEFORE(next, mn, free_link); 171 mn->type = MNODE_FREE; 172 TAILQ_REMOVE(&st_list, next, link); 173 TAILQ_REMOVE(&free_list, next, free_link); 174 stmem_total += mn->size + sizeof(struct mem_node); 175 mn->size += next->size + sizeof(struct mem_node); 176 } 177 if (prev->type == MNODE_FREE) { 178 /* 179 * if prev is: a valid node and a free node. ==> merge 180 */ 181 if (mn->type != MNODE_FREE) 182 stmem_total += mn->size + sizeof(struct mem_node); 183 else { 184 /* already on free list */ 185 TAILQ_REMOVE(&free_list, mn, free_link); 186 mn->type = MNODE_USED; 187 stmem_total += sizeof(struct mem_node); 188 } 189 TAILQ_REMOVE(&st_list, mn, link); 190 prev->size += mn->size + sizeof(struct mem_node); 191 } else if (mn->type != MNODE_FREE) { 192 /* 193 * we still are not on free list and we need to be. 194 * <-- | --> 195 */ 196 while (next != NULL && prev != NULL) { 197 if (next->type == MNODE_FREE) { 198 TAILQ_INSERT_BEFORE(next, mn, free_link); 199 mn->type = MNODE_FREE; 200 break; 201 } 202 if (prev->type == MNODE_FREE) { 203 TAILQ_INSERT_AFTER(&free_list, prev, mn, 204 free_link); 205 mn->type = MNODE_FREE; 206 break; 207 } 208 prev = TAILQ_PREV(prev, stlist, link); 209 next = TAILQ_NEXT(next, link); 210 } 211 if (mn->type != MNODE_FREE) { 212 if (next == NULL) { 213 /* 214 * we are not on list so we can add 215 * ourselves to the tail. (we walked to it.) 216 */ 217 TAILQ_INSERT_TAIL(&free_list,mn,free_link); 218 } else { 219 TAILQ_INSERT_HEAD(&free_list,mn,free_link); 220 } 221 mn->type = MNODE_FREE; 222 } 223 stmem_total += mn->size;/* add our helpings to the pool. */ 224 } 225 splx(s); 226 } 227