1/* 2 * Copyright 1998 Massachusetts Institute of Technology 3 * 4 * Permission to use, copy, modify, and distribute this software and 5 * its documentation for any purpose and without fee is hereby 6 * granted, provided that both the above copyright notice and this 7 * permission notice appear in all copies, that both the above 8 * copyright notice and this permission notice appear in all 9 * supporting documentation, and that the name of M.I.T. not be used 10 * in advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. M.I.T. makes 12 * no representations about the suitability of this software for any 13 * purpose. It is provided "as is" without express or implied 14 * warranty. 15 * 16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 *
| 1/* 2 * Copyright 1998 Massachusetts Institute of Technology 3 * 4 * Permission to use, copy, modify, and distribute this software and 5 * its documentation for any purpose and without fee is hereby 6 * granted, provided that both the above copyright notice and this 7 * permission notice appear in all copies, that both the above 8 * copyright notice and this permission notice appear in all 9 * supporting documentation, and that the name of M.I.T. not be used 10 * in advertising or publicity pertaining to distribution of the 11 * software without specific, written prior permission. M.I.T. makes 12 * no representations about the suitability of this software for any 13 * purpose. It is provided "as is" without express or implied 14 * warranty. 15 * 16 * THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS 17 * ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE, 18 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT 20 * SHALL M.I.T. BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 23 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 24 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 25 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 26 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 *
|
29 * $Id: subr_rman.c,v 1.5 1999/03/29 08:30:17 dfr Exp $
| 29 * $Id: subr_rman.c,v 1.6 1999/04/11 02:27:06 eivind Exp $
|
30 */ 31 32/* 33 * The kernel resource manager. This code is responsible for keeping track 34 * of hardware resources which are apportioned out to various drivers. 35 * It does not actually assign those resources, and it is not expected 36 * that end-device drivers will call into this code directly. Rather, 37 * the code which implements the buses that those devices are attached to, 38 * and the code which manages CPU resources, will call this code, and the 39 * end-device drivers will make upcalls to that code to actually perform 40 * the allocation. 41 * 42 * There are two sorts of resources managed by this code. The first is 43 * the more familiar array (RMAN_ARRAY) type; resources in this class 44 * consist of a sequence of individually-allocatable objects which have 45 * been numbered in some well-defined order. Most of the resources 46 * are of this type, as it is the most familiar. The second type is 47 * called a gauge (RMAN_GAUGE), and models fungible resources (i.e., 48 * resources in which each instance is indistinguishable from every 49 * other instance). The principal anticipated application of gauges 50 * is in the context of power consumption, where a bus may have a specific 51 * power budget which all attached devices share. RMAN_GAUGE is not 52 * implemented yet. 53 * 54 * For array resources, we make one simplifying assumption: two clients 55 * sharing the same resource must use the same range of indices. That 56 * is to say, sharing of overlapping-but-not-identical regions is not 57 * permitted. 58 */ 59 60#include <sys/param.h> 61#include <sys/systm.h> 62#include <sys/kernel.h> 63#include <sys/lock.h> 64#include <sys/malloc.h>
| 30 */ 31 32/* 33 * The kernel resource manager. This code is responsible for keeping track 34 * of hardware resources which are apportioned out to various drivers. 35 * It does not actually assign those resources, and it is not expected 36 * that end-device drivers will call into this code directly. Rather, 37 * the code which implements the buses that those devices are attached to, 38 * and the code which manages CPU resources, will call this code, and the 39 * end-device drivers will make upcalls to that code to actually perform 40 * the allocation. 41 * 42 * There are two sorts of resources managed by this code. The first is 43 * the more familiar array (RMAN_ARRAY) type; resources in this class 44 * consist of a sequence of individually-allocatable objects which have 45 * been numbered in some well-defined order. Most of the resources 46 * are of this type, as it is the most familiar. The second type is 47 * called a gauge (RMAN_GAUGE), and models fungible resources (i.e., 48 * resources in which each instance is indistinguishable from every 49 * other instance). The principal anticipated application of gauges 50 * is in the context of power consumption, where a bus may have a specific 51 * power budget which all attached devices share. RMAN_GAUGE is not 52 * implemented yet. 53 * 54 * For array resources, we make one simplifying assumption: two clients 55 * sharing the same resource must use the same range of indices. That 56 * is to say, sharing of overlapping-but-not-identical regions is not 57 * permitted. 58 */ 59 60#include <sys/param.h> 61#include <sys/systm.h> 62#include <sys/kernel.h> 63#include <sys/lock.h> 64#include <sys/malloc.h>
|
65#include <sys/rman.h>
| |
66#include <sys/bus.h> /* XXX debugging */
| 65#include <sys/bus.h> /* XXX debugging */
|
| 66#include <machine/bus.h> 67#include <sys/rman.h>
|
67 68static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager"); 69 70struct rman_head rman_head; 71#ifndef NULL_SIMPLELOCKS 72static struct simplelock rman_lock; /* mutex to protect rman_head */ 73#endif 74static int int_rman_activate_resource(struct rman *rm, struct resource *r, 75 struct resource **whohas);
| 68 69static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager"); 70 71struct rman_head rman_head; 72#ifndef NULL_SIMPLELOCKS 73static struct simplelock rman_lock; /* mutex to protect rman_head */ 74#endif 75static int int_rman_activate_resource(struct rman *rm, struct resource *r, 76 struct resource **whohas);
|
| 77static int int_rman_deactivate_resource(struct resource *r);
|
76static int int_rman_release_resource(struct rman *rm, struct resource *r); 77 78#define CIRCLEQ_TERMCOND(var, head) (var == (void *)&(head)) 79 80int 81rman_init(struct rman *rm) 82{ 83 static int once; 84 85 if (once == 0) { 86 once = 1; 87 TAILQ_INIT(&rman_head); 88 simple_lock_init(&rman_lock); 89 } 90 91 if (rm->rm_type == RMAN_UNINIT) 92 panic("rman_init"); 93 if (rm->rm_type == RMAN_GAUGE) 94 panic("implement RMAN_GAUGE"); 95 96 CIRCLEQ_INIT(&rm->rm_list); 97 rm->rm_slock = malloc(sizeof *rm->rm_slock, M_RMAN, M_NOWAIT); 98 if (rm->rm_slock == 0) 99 return ENOMEM; 100 simple_lock_init(rm->rm_slock); 101 102 simple_lock(&rman_lock); 103 TAILQ_INSERT_TAIL(&rman_head, rm, rm_link); 104 simple_unlock(&rman_lock); 105 return 0; 106} 107 108/* 109 * NB: this interface is not robust against programming errors which 110 * add multiple copies of the same region. 111 */ 112int 113rman_manage_region(struct rman *rm, u_long start, u_long end) 114{ 115 struct resource *r, *s; 116 117 r = malloc(sizeof *r, M_RMAN, M_NOWAIT); 118 if (r == 0) 119 return ENOMEM;
| 78static int int_rman_release_resource(struct rman *rm, struct resource *r); 79 80#define CIRCLEQ_TERMCOND(var, head) (var == (void *)&(head)) 81 82int 83rman_init(struct rman *rm) 84{ 85 static int once; 86 87 if (once == 0) { 88 once = 1; 89 TAILQ_INIT(&rman_head); 90 simple_lock_init(&rman_lock); 91 } 92 93 if (rm->rm_type == RMAN_UNINIT) 94 panic("rman_init"); 95 if (rm->rm_type == RMAN_GAUGE) 96 panic("implement RMAN_GAUGE"); 97 98 CIRCLEQ_INIT(&rm->rm_list); 99 rm->rm_slock = malloc(sizeof *rm->rm_slock, M_RMAN, M_NOWAIT); 100 if (rm->rm_slock == 0) 101 return ENOMEM; 102 simple_lock_init(rm->rm_slock); 103 104 simple_lock(&rman_lock); 105 TAILQ_INSERT_TAIL(&rman_head, rm, rm_link); 106 simple_unlock(&rman_lock); 107 return 0; 108} 109 110/* 111 * NB: this interface is not robust against programming errors which 112 * add multiple copies of the same region. 113 */ 114int 115rman_manage_region(struct rman *rm, u_long start, u_long end) 116{ 117 struct resource *r, *s; 118 119 r = malloc(sizeof *r, M_RMAN, M_NOWAIT); 120 if (r == 0) 121 return ENOMEM;
|
| 122 bzero(r, sizeof *r);
|
120 r->r_sharehead = 0; 121 r->r_start = start; 122 r->r_end = end; 123 r->r_flags = 0; 124 r->r_dev = 0; 125 r->r_rm = rm; 126 127 simple_lock(rm->rm_slock); 128 for (s = rm->rm_list.cqh_first; 129 !CIRCLEQ_TERMCOND(s, rm->rm_list) && s->r_end < r->r_start; 130 s = s->r_link.cqe_next) 131 ; 132 133 if (CIRCLEQ_TERMCOND(s, rm->rm_list)) { 134 CIRCLEQ_INSERT_TAIL(&rm->rm_list, r, r_link); 135 } else { 136 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, s, r, r_link); 137 } 138 139 simple_unlock(rm->rm_slock); 140 return 0; 141} 142 143int 144rman_fini(struct rman *rm) 145{ 146 struct resource *r; 147 148 simple_lock(rm->rm_slock); 149 for (r = rm->rm_list.cqh_first; !CIRCLEQ_TERMCOND(r, rm->rm_list); 150 r = r->r_link.cqe_next) {
| 123 r->r_sharehead = 0; 124 r->r_start = start; 125 r->r_end = end; 126 r->r_flags = 0; 127 r->r_dev = 0; 128 r->r_rm = rm; 129 130 simple_lock(rm->rm_slock); 131 for (s = rm->rm_list.cqh_first; 132 !CIRCLEQ_TERMCOND(s, rm->rm_list) && s->r_end < r->r_start; 133 s = s->r_link.cqe_next) 134 ; 135 136 if (CIRCLEQ_TERMCOND(s, rm->rm_list)) { 137 CIRCLEQ_INSERT_TAIL(&rm->rm_list, r, r_link); 138 } else { 139 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, s, r, r_link); 140 } 141 142 simple_unlock(rm->rm_slock); 143 return 0; 144} 145 146int 147rman_fini(struct rman *rm) 148{ 149 struct resource *r; 150 151 simple_lock(rm->rm_slock); 152 for (r = rm->rm_list.cqh_first; !CIRCLEQ_TERMCOND(r, rm->rm_list); 153 r = r->r_link.cqe_next) {
|
151 if (r->r_flags & RF_ALLOCATED)
| 154 if (r->r_flags & RF_ALLOCATED) { 155 simple_unlock(rm->rm_slock);
|
152 return EBUSY;
| 156 return EBUSY;
|
| 157 }
|
153 } 154 155 /* 156 * There really should only be one of these if we are in this 157 * state and the code is working properly, but it can't hurt. 158 */ 159 for (r = rm->rm_list.cqh_first; !CIRCLEQ_TERMCOND(r, rm->rm_list); 160 r = rm->rm_list.cqh_first) { 161 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 162 free(r, M_RMAN); 163 } 164 simple_unlock(rm->rm_slock); 165 simple_lock(&rman_lock); 166 TAILQ_REMOVE(&rman_head, rm, rm_link); 167 simple_unlock(&rman_lock); 168 free(rm->rm_slock, M_RMAN); 169 170 return 0; 171} 172 173struct resource * 174rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count, 175 u_int flags, struct device *dev) 176{ 177 u_int want_activate; 178 struct resource *r, *s, *rv; 179 u_long rstart, rend; 180 181 rv = 0; 182 183#ifdef RMAN_DEBUG 184 printf("rman_reserve_resource: <%s> request: [%#lx, %#lx], length " 185 "%#lx, flags %u, device %s%d\n", rm->rm_descr, start, end, 186 count, flags, device_get_name(dev), device_get_unit(dev)); 187#endif /* RMAN_DEBUG */ 188 want_activate = (flags & RF_ACTIVE); 189 flags &= ~RF_ACTIVE; 190 191 simple_lock(rm->rm_slock); 192 193 for (r = rm->rm_list.cqh_first; 194 !CIRCLEQ_TERMCOND(r, rm->rm_list) && r->r_end < start; 195 r = r->r_link.cqe_next) 196 ; 197 198 if (CIRCLEQ_TERMCOND(r, rm->rm_list)) { 199#ifdef RMAN_DEBUG 200 printf("could not find a region\n"); 201#endif RMAN_DEBUG 202 goto out; 203 } 204 205 /* 206 * First try to find an acceptable totally-unshared region. 207 */ 208 for (s = r; !CIRCLEQ_TERMCOND(s, rm->rm_list); 209 s = s->r_link.cqe_next) { 210#ifdef RMAN_DEBUG 211 printf("considering [%#lx, %#lx]\n", s->r_start, s->r_end); 212#endif /* RMAN_DEBUG */ 213 if (s->r_start > end) { 214#ifdef RMAN_DEBUG 215 printf("s->r_start (%#lx) > end (%#lx)\n", s->r_start, end); 216#endif /* RMAN_DEBUG */ 217 break; 218 } 219 if (s->r_flags & RF_ALLOCATED) { 220#ifdef RMAN_DEBUG 221 printf("region is allocated\n"); 222#endif /* RMAN_DEBUG */ 223 continue; 224 } 225 rstart = max(s->r_start, start); 226 rend = min(s->r_end, max(start + count, end)); 227#ifdef RMAN_DEBUG 228 printf("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n", 229 rstart, rend, (rend - rstart + 1), count); 230#endif /* RMAN_DEBUG */ 231 232 if ((rend - rstart + 1) >= count) { 233#ifdef RMAN_DEBUG 234 printf("candidate region: [%#lx, %#lx], size %#lx\n", 235 rend, rstart, (rend - rstart + 1)); 236#endif /* RMAN_DEBUG */ 237 if ((s->r_end - s->r_start + 1) == count) { 238#ifdef RMAN_DEBUG 239 printf("candidate region is entire chunk\n"); 240#endif /* RMAN_DEBUG */ 241 rv = s; 242 rv->r_flags |= RF_ALLOCATED; 243 rv->r_dev = dev; 244 goto out; 245 } 246 247 /* 248 * If s->r_start < rstart and 249 * s->r_end > rstart + count - 1, then 250 * we need to split the region into three pieces 251 * (the middle one will get returned to the user). 252 * Otherwise, we are allocating at either the 253 * beginning or the end of s, so we only need to 254 * split it in two. The first case requires 255 * two new allocations; the second requires but one. 256 */
| 158 } 159 160 /* 161 * There really should only be one of these if we are in this 162 * state and the code is working properly, but it can't hurt. 163 */ 164 for (r = rm->rm_list.cqh_first; !CIRCLEQ_TERMCOND(r, rm->rm_list); 165 r = rm->rm_list.cqh_first) { 166 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 167 free(r, M_RMAN); 168 } 169 simple_unlock(rm->rm_slock); 170 simple_lock(&rman_lock); 171 TAILQ_REMOVE(&rman_head, rm, rm_link); 172 simple_unlock(&rman_lock); 173 free(rm->rm_slock, M_RMAN); 174 175 return 0; 176} 177 178struct resource * 179rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count, 180 u_int flags, struct device *dev) 181{ 182 u_int want_activate; 183 struct resource *r, *s, *rv; 184 u_long rstart, rend; 185 186 rv = 0; 187 188#ifdef RMAN_DEBUG 189 printf("rman_reserve_resource: <%s> request: [%#lx, %#lx], length " 190 "%#lx, flags %u, device %s%d\n", rm->rm_descr, start, end, 191 count, flags, device_get_name(dev), device_get_unit(dev)); 192#endif /* RMAN_DEBUG */ 193 want_activate = (flags & RF_ACTIVE); 194 flags &= ~RF_ACTIVE; 195 196 simple_lock(rm->rm_slock); 197 198 for (r = rm->rm_list.cqh_first; 199 !CIRCLEQ_TERMCOND(r, rm->rm_list) && r->r_end < start; 200 r = r->r_link.cqe_next) 201 ; 202 203 if (CIRCLEQ_TERMCOND(r, rm->rm_list)) { 204#ifdef RMAN_DEBUG 205 printf("could not find a region\n"); 206#endif RMAN_DEBUG 207 goto out; 208 } 209 210 /* 211 * First try to find an acceptable totally-unshared region. 212 */ 213 for (s = r; !CIRCLEQ_TERMCOND(s, rm->rm_list); 214 s = s->r_link.cqe_next) { 215#ifdef RMAN_DEBUG 216 printf("considering [%#lx, %#lx]\n", s->r_start, s->r_end); 217#endif /* RMAN_DEBUG */ 218 if (s->r_start > end) { 219#ifdef RMAN_DEBUG 220 printf("s->r_start (%#lx) > end (%#lx)\n", s->r_start, end); 221#endif /* RMAN_DEBUG */ 222 break; 223 } 224 if (s->r_flags & RF_ALLOCATED) { 225#ifdef RMAN_DEBUG 226 printf("region is allocated\n"); 227#endif /* RMAN_DEBUG */ 228 continue; 229 } 230 rstart = max(s->r_start, start); 231 rend = min(s->r_end, max(start + count, end)); 232#ifdef RMAN_DEBUG 233 printf("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n", 234 rstart, rend, (rend - rstart + 1), count); 235#endif /* RMAN_DEBUG */ 236 237 if ((rend - rstart + 1) >= count) { 238#ifdef RMAN_DEBUG 239 printf("candidate region: [%#lx, %#lx], size %#lx\n", 240 rend, rstart, (rend - rstart + 1)); 241#endif /* RMAN_DEBUG */ 242 if ((s->r_end - s->r_start + 1) == count) { 243#ifdef RMAN_DEBUG 244 printf("candidate region is entire chunk\n"); 245#endif /* RMAN_DEBUG */ 246 rv = s; 247 rv->r_flags |= RF_ALLOCATED; 248 rv->r_dev = dev; 249 goto out; 250 } 251 252 /* 253 * If s->r_start < rstart and 254 * s->r_end > rstart + count - 1, then 255 * we need to split the region into three pieces 256 * (the middle one will get returned to the user). 257 * Otherwise, we are allocating at either the 258 * beginning or the end of s, so we only need to 259 * split it in two. The first case requires 260 * two new allocations; the second requires but one. 261 */
|
257 rv = malloc(sizeof *r, M_RMAN, M_NOWAIT);
| 262 rv = malloc(sizeof *rv, M_RMAN, M_NOWAIT);
|
258 if (rv == 0) 259 goto out;
| 263 if (rv == 0) 264 goto out;
|
| 265 bzero(rv, sizeof *rv);
|
260 rv->r_start = rstart; 261 rv->r_end = rstart + count - 1; 262 rv->r_flags = flags | RF_ALLOCATED; 263 rv->r_dev = dev; 264 rv->r_sharehead = 0;
| 266 rv->r_start = rstart; 267 rv->r_end = rstart + count - 1; 268 rv->r_flags = flags | RF_ALLOCATED; 269 rv->r_dev = dev; 270 rv->r_sharehead = 0;
|
| 271 rv->r_rm = rm;
|
265 266 if (s->r_start < rv->r_start && s->r_end > rv->r_end) { 267#ifdef RMAN_DEBUG 268 printf("splitting region in three parts: " 269 "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n", 270 s->r_start, rv->r_start - 1, 271 rv->r_start, rv->r_end, 272 rv->r_end + 1, s->r_end); 273#endif /* RMAN_DEBUG */ 274 /* 275 * We are allocating in the middle. 276 */ 277 r = malloc(sizeof *r, M_RMAN, M_NOWAIT); 278 if (r == 0) { 279 free(rv, M_RMAN); 280 rv = 0; 281 goto out; 282 }
| 272 273 if (s->r_start < rv->r_start && s->r_end > rv->r_end) { 274#ifdef RMAN_DEBUG 275 printf("splitting region in three parts: " 276 "[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n", 277 s->r_start, rv->r_start - 1, 278 rv->r_start, rv->r_end, 279 rv->r_end + 1, s->r_end); 280#endif /* RMAN_DEBUG */ 281 /* 282 * We are allocating in the middle. 283 */ 284 r = malloc(sizeof *r, M_RMAN, M_NOWAIT); 285 if (r == 0) { 286 free(rv, M_RMAN); 287 rv = 0; 288 goto out; 289 }
|
| 290 bzero(r, sizeof *r);
|
283 r->r_start = rv->r_end + 1; 284 r->r_end = s->r_end; 285 r->r_flags = s->r_flags; 286 r->r_dev = 0; 287 r->r_sharehead = 0;
| 291 r->r_start = rv->r_end + 1; 292 r->r_end = s->r_end; 293 r->r_flags = s->r_flags; 294 r->r_dev = 0; 295 r->r_sharehead = 0;
|
| 296 r->r_rm = rm;
|
288 s->r_end = rv->r_start - 1; 289 CIRCLEQ_INSERT_AFTER(&rm->rm_list, s, rv, 290 r_link); 291 CIRCLEQ_INSERT_AFTER(&rm->rm_list, rv, r, 292 r_link); 293 } else if (s->r_start == rv->r_start) { 294#ifdef RMAN_DEBUG 295 printf("allocating from the beginning\n"); 296#endif /* RMAN_DEBUG */ 297 /* 298 * We are allocating at the beginning. 299 */ 300 s->r_start = rv->r_end + 1; 301 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, s, rv, 302 r_link); 303 } else { 304#ifdef RMAN_DEBUG 305 printf("allocating at the end\n"); 306#endif /* RMAN_DEBUG */ 307 /* 308 * We are allocating at the end. 309 */ 310 s->r_end = rv->r_start - 1; 311 CIRCLEQ_INSERT_AFTER(&rm->rm_list, s, rv, 312 r_link); 313 } 314 goto out; 315 } 316 } 317 318 /* 319 * Now find an acceptable shared region, if the client's requirements 320 * allow sharing. By our implementation restriction, a candidate 321 * region must match exactly by both size and sharing type in order 322 * to be considered compatible with the client's request. (The 323 * former restriction could probably be lifted without too much 324 * additional work, but this does not seem warranted.) 325 */ 326#ifdef RMAN_DEBUG 327 printf("no unshared regions found\n"); 328#endif /* RMAN_DEBUG */ 329 if ((flags & (RF_SHAREABLE | RF_TIMESHARE)) == 0) 330 goto out; 331 332 for (s = r; !CIRCLEQ_TERMCOND(s, rm->rm_list); 333 s = s->r_link.cqe_next) { 334 if (s->r_start > end) 335 break; 336 if ((s->r_flags & flags) != flags) 337 continue; 338 rstart = max(s->r_start, start); 339 rend = min(s->r_end, max(start + count, end)); 340 if (s->r_start >= start && s->r_end <= end 341 && (s->r_end - s->r_start + 1) == count) { 342 rv = malloc(sizeof *rv, M_RMAN, M_NOWAIT); 343 if (rv == 0) 344 goto out;
| 297 s->r_end = rv->r_start - 1; 298 CIRCLEQ_INSERT_AFTER(&rm->rm_list, s, rv, 299 r_link); 300 CIRCLEQ_INSERT_AFTER(&rm->rm_list, rv, r, 301 r_link); 302 } else if (s->r_start == rv->r_start) { 303#ifdef RMAN_DEBUG 304 printf("allocating from the beginning\n"); 305#endif /* RMAN_DEBUG */ 306 /* 307 * We are allocating at the beginning. 308 */ 309 s->r_start = rv->r_end + 1; 310 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, s, rv, 311 r_link); 312 } else { 313#ifdef RMAN_DEBUG 314 printf("allocating at the end\n"); 315#endif /* RMAN_DEBUG */ 316 /* 317 * We are allocating at the end. 318 */ 319 s->r_end = rv->r_start - 1; 320 CIRCLEQ_INSERT_AFTER(&rm->rm_list, s, rv, 321 r_link); 322 } 323 goto out; 324 } 325 } 326 327 /* 328 * Now find an acceptable shared region, if the client's requirements 329 * allow sharing. By our implementation restriction, a candidate 330 * region must match exactly by both size and sharing type in order 331 * to be considered compatible with the client's request. (The 332 * former restriction could probably be lifted without too much 333 * additional work, but this does not seem warranted.) 334 */ 335#ifdef RMAN_DEBUG 336 printf("no unshared regions found\n"); 337#endif /* RMAN_DEBUG */ 338 if ((flags & (RF_SHAREABLE | RF_TIMESHARE)) == 0) 339 goto out; 340 341 for (s = r; !CIRCLEQ_TERMCOND(s, rm->rm_list); 342 s = s->r_link.cqe_next) { 343 if (s->r_start > end) 344 break; 345 if ((s->r_flags & flags) != flags) 346 continue; 347 rstart = max(s->r_start, start); 348 rend = min(s->r_end, max(start + count, end)); 349 if (s->r_start >= start && s->r_end <= end 350 && (s->r_end - s->r_start + 1) == count) { 351 rv = malloc(sizeof *rv, M_RMAN, M_NOWAIT); 352 if (rv == 0) 353 goto out;
|
| 354 bzero(rv, sizeof *rv);
|
345 rv->r_start = s->r_start; 346 rv->r_end = s->r_end; 347 rv->r_flags = s->r_flags & 348 (RF_ALLOCATED | RF_SHAREABLE | RF_TIMESHARE); 349 rv->r_dev = dev; 350 rv->r_rm = rm; 351 if (s->r_sharehead == 0) { 352 s->r_sharehead = malloc(sizeof *s->r_sharehead, 353 M_RMAN, M_NOWAIT); 354 if (s->r_sharehead == 0) { 355 free(rv, M_RMAN); 356 rv = 0; 357 goto out; 358 }
| 355 rv->r_start = s->r_start; 356 rv->r_end = s->r_end; 357 rv->r_flags = s->r_flags & 358 (RF_ALLOCATED | RF_SHAREABLE | RF_TIMESHARE); 359 rv->r_dev = dev; 360 rv->r_rm = rm; 361 if (s->r_sharehead == 0) { 362 s->r_sharehead = malloc(sizeof *s->r_sharehead, 363 M_RMAN, M_NOWAIT); 364 if (s->r_sharehead == 0) { 365 free(rv, M_RMAN); 366 rv = 0; 367 goto out; 368 }
|
| 369 bzero(s->r_sharehead, sizeof *s->r_sharehead);
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359 LIST_INIT(s->r_sharehead); 360 LIST_INSERT_HEAD(s->r_sharehead, s, 361 r_sharelink); 362 s->r_flags |= RF_FIRSTSHARE; 363 } 364 rv->r_sharehead = s->r_sharehead; 365 LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink); 366 goto out; 367 } 368 } 369 370 /* 371 * We couldn't find anything. 372 */ 373out: 374 /* 375 * If the user specified RF_ACTIVE in the initial flags, 376 * which is reflected in `want_activate', we attempt to atomically 377 * activate the resource. If this fails, we release the resource 378 * and indicate overall failure. (This behavior probably doesn't 379 * make sense for RF_TIMESHARE-type resources.) 380 */ 381 if (rv && want_activate) { 382 struct resource *whohas; 383 if (int_rman_activate_resource(rm, rv, &whohas)) { 384 int_rman_release_resource(rm, rv); 385 rv = 0; 386 } 387 } 388 389 simple_unlock(rm->rm_slock); 390 return (rv); 391} 392 393static int 394int_rman_activate_resource(struct rman *rm, struct resource *r, 395 struct resource **whohas) 396{ 397 struct resource *s; 398 int ok; 399 400 /* 401 * If we are not timesharing, then there is nothing much to do. 402 * If we already have the resource, then there is nothing at all to do. 403 * If we are not on a sharing list with anybody else, then there is 404 * little to do. 405 */ 406 if ((r->r_flags & RF_TIMESHARE) == 0 407 || (r->r_flags & RF_ACTIVE) != 0 408 || r->r_sharehead == 0) { 409 r->r_flags |= RF_ACTIVE; 410 return 0; 411 } 412 413 ok = 1; 414 for (s = r->r_sharehead->lh_first; s && ok; 415 s = s->r_sharelink.le_next) { 416 if ((s->r_flags & RF_ACTIVE) != 0) { 417 ok = 0; 418 *whohas = s; 419 } 420 } 421 if (ok) { 422 r->r_flags |= RF_ACTIVE; 423 return 0; 424 } 425 return EBUSY; 426} 427 428int 429rman_activate_resource(struct resource *r) 430{ 431 int rv; 432 struct resource *whohas; 433 struct rman *rm; 434 435 rm = r->r_rm; 436 simple_lock(rm->rm_slock); 437 rv = int_rman_activate_resource(rm, r, &whohas); 438 simple_unlock(rm->rm_slock); 439 return rv; 440} 441 442int 443rman_await_resource(struct resource *r, int pri, int timo) 444{ 445 int rv, s; 446 struct resource *whohas; 447 struct rman *rm; 448 449 rm = r->r_rm; 450 for (;;) { 451 simple_lock(rm->rm_slock); 452 rv = int_rman_activate_resource(rm, r, &whohas); 453 if (rv != EBUSY)
| 370 LIST_INIT(s->r_sharehead); 371 LIST_INSERT_HEAD(s->r_sharehead, s, 372 r_sharelink); 373 s->r_flags |= RF_FIRSTSHARE; 374 } 375 rv->r_sharehead = s->r_sharehead; 376 LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink); 377 goto out; 378 } 379 } 380 381 /* 382 * We couldn't find anything. 383 */ 384out: 385 /* 386 * If the user specified RF_ACTIVE in the initial flags, 387 * which is reflected in `want_activate', we attempt to atomically 388 * activate the resource. If this fails, we release the resource 389 * and indicate overall failure. (This behavior probably doesn't 390 * make sense for RF_TIMESHARE-type resources.) 391 */ 392 if (rv && want_activate) { 393 struct resource *whohas; 394 if (int_rman_activate_resource(rm, rv, &whohas)) { 395 int_rman_release_resource(rm, rv); 396 rv = 0; 397 } 398 } 399 400 simple_unlock(rm->rm_slock); 401 return (rv); 402} 403 404static int 405int_rman_activate_resource(struct rman *rm, struct resource *r, 406 struct resource **whohas) 407{ 408 struct resource *s; 409 int ok; 410 411 /* 412 * If we are not timesharing, then there is nothing much to do. 413 * If we already have the resource, then there is nothing at all to do. 414 * If we are not on a sharing list with anybody else, then there is 415 * little to do. 416 */ 417 if ((r->r_flags & RF_TIMESHARE) == 0 418 || (r->r_flags & RF_ACTIVE) != 0 419 || r->r_sharehead == 0) { 420 r->r_flags |= RF_ACTIVE; 421 return 0; 422 } 423 424 ok = 1; 425 for (s = r->r_sharehead->lh_first; s && ok; 426 s = s->r_sharelink.le_next) { 427 if ((s->r_flags & RF_ACTIVE) != 0) { 428 ok = 0; 429 *whohas = s; 430 } 431 } 432 if (ok) { 433 r->r_flags |= RF_ACTIVE; 434 return 0; 435 } 436 return EBUSY; 437} 438 439int 440rman_activate_resource(struct resource *r) 441{ 442 int rv; 443 struct resource *whohas; 444 struct rman *rm; 445 446 rm = r->r_rm; 447 simple_lock(rm->rm_slock); 448 rv = int_rman_activate_resource(rm, r, &whohas); 449 simple_unlock(rm->rm_slock); 450 return rv; 451} 452 453int 454rman_await_resource(struct resource *r, int pri, int timo) 455{ 456 int rv, s; 457 struct resource *whohas; 458 struct rman *rm; 459 460 rm = r->r_rm; 461 for (;;) { 462 simple_lock(rm->rm_slock); 463 rv = int_rman_activate_resource(rm, r, &whohas); 464 if (rv != EBUSY)
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454 return (rv);
| 465 return (rv); /* returns with simplelock */
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455 456 if (r->r_sharehead == 0) 457 panic("rman_await_resource"); 458 /* 459 * splhigh hopefully will prevent a race between 460 * simple_unlock and tsleep where a process 461 * could conceivably get in and release the resource 462 * before we have a chance to sleep on it. 463 */ 464 s = splhigh(); 465 whohas->r_flags |= RF_WANTED; 466 simple_unlock(rm->rm_slock); 467 rv = tsleep(r->r_sharehead, pri, "rmwait", timo); 468 if (rv) { 469 splx(s); 470 return rv; 471 } 472 simple_lock(rm->rm_slock); 473 splx(s); 474 } 475} 476
| 466 467 if (r->r_sharehead == 0) 468 panic("rman_await_resource"); 469 /* 470 * splhigh hopefully will prevent a race between 471 * simple_unlock and tsleep where a process 472 * could conceivably get in and release the resource 473 * before we have a chance to sleep on it. 474 */ 475 s = splhigh(); 476 whohas->r_flags |= RF_WANTED; 477 simple_unlock(rm->rm_slock); 478 rv = tsleep(r->r_sharehead, pri, "rmwait", timo); 479 if (rv) { 480 splx(s); 481 return rv; 482 } 483 simple_lock(rm->rm_slock); 484 splx(s); 485 } 486} 487
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477int 478rman_deactivate_resource(struct resource *r)
| 488static int 489int_rman_deactivate_resource(struct resource *r)
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479{ 480 struct rman *rm; 481 482 rm = r->r_rm;
| 490{ 491 struct rman *rm; 492 493 rm = r->r_rm;
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483 simple_lock(rm->rm_slock);
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484 r->r_flags &= ~RF_ACTIVE; 485 if (r->r_flags & RF_WANTED) { 486 r->r_flags &= ~RF_WANTED; 487 wakeup(r->r_sharehead); 488 }
| 494 r->r_flags &= ~RF_ACTIVE; 495 if (r->r_flags & RF_WANTED) { 496 r->r_flags &= ~RF_WANTED; 497 wakeup(r->r_sharehead); 498 }
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| 499 return 0; 500} 501 502int 503rman_deactivate_resource(struct resource *r) 504{ 505 struct rman *rm; 506 507 rm = r->r_rm; 508 simple_lock(rm->rm_slock); 509 int_rman_deactivate_resource(r);
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489 simple_unlock(rm->rm_slock); 490 return 0; 491} 492 493static int 494int_rman_release_resource(struct rman *rm, struct resource *r) 495{ 496 struct resource *s, *t; 497 498 if (r->r_flags & RF_ACTIVE)
| 510 simple_unlock(rm->rm_slock); 511 return 0; 512} 513 514static int 515int_rman_release_resource(struct rman *rm, struct resource *r) 516{ 517 struct resource *s, *t; 518 519 if (r->r_flags & RF_ACTIVE)
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499 return EBUSY;
| 520 int_rman_deactivate_resource(r);
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500 501 /* 502 * Check for a sharing list first. If there is one, then we don't 503 * have to think as hard. 504 */ 505 if (r->r_sharehead) { 506 /* 507 * If a sharing list exists, then we know there are at 508 * least two sharers. 509 * 510 * If we are in the main circleq, appoint someone else. 511 */ 512 LIST_REMOVE(r, r_sharelink); 513 s = r->r_sharehead->lh_first; 514 if (r->r_flags & RF_FIRSTSHARE) { 515 s->r_flags |= RF_FIRSTSHARE; 516 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, r, s, r_link); 517 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 518 } 519 520 /* 521 * Make sure that the sharing list goes away completely 522 * if the resource is no longer being shared at all. 523 */ 524 if (s->r_sharelink.le_next == 0) { 525 free(s->r_sharehead, M_RMAN); 526 s->r_sharehead = 0; 527 s->r_flags &= ~RF_FIRSTSHARE; 528 } 529 goto out; 530 } 531 532 /* 533 * Look at the adjacent resources in the list and see if our 534 * segment can be merged with any of them. 535 */ 536 s = r->r_link.cqe_prev; 537 t = r->r_link.cqe_next; 538 539 if (s != (void *)&rm->rm_list && (s->r_flags & RF_ALLOCATED) == 0 540 && t != (void *)&rm->rm_list && (t->r_flags & RF_ALLOCATED) == 0) { 541 /* 542 * Merge all three segments. 543 */ 544 s->r_end = t->r_end; 545 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 546 CIRCLEQ_REMOVE(&rm->rm_list, t, r_link); 547 free(t, M_RMAN); 548 } else if (s != (void *)&rm->rm_list 549 && (s->r_flags & RF_ALLOCATED) == 0) { 550 /* 551 * Merge previous segment with ours. 552 */ 553 s->r_end = r->r_end; 554 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 555 } else if (t != (void *)&rm->rm_list 556 && (t->r_flags & RF_ALLOCATED) == 0) { 557 /* 558 * Merge next segment with ours. 559 */ 560 t->r_start = r->r_start; 561 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 562 } else { 563 /* 564 * At this point, we know there is nothing we 565 * can potentially merge with, because on each 566 * side, there is either nothing there or what is 567 * there is still allocated. In that case, we don't 568 * want to remove r from the list; we simply want to 569 * change it to an unallocated region and return 570 * without freeing anything. 571 */ 572 r->r_flags &= ~RF_ALLOCATED; 573 return 0; 574 } 575 576out: 577 free(r, M_RMAN); 578 return 0; 579} 580 581int 582rman_release_resource(struct resource *r) 583{ 584 int rv; 585 struct rman *rm = r->r_rm; 586 587 simple_lock(rm->rm_slock); 588 rv = int_rman_release_resource(rm, r); 589 simple_unlock(rm->rm_slock); 590 return (rv); 591}
| 521 522 /* 523 * Check for a sharing list first. If there is one, then we don't 524 * have to think as hard. 525 */ 526 if (r->r_sharehead) { 527 /* 528 * If a sharing list exists, then we know there are at 529 * least two sharers. 530 * 531 * If we are in the main circleq, appoint someone else. 532 */ 533 LIST_REMOVE(r, r_sharelink); 534 s = r->r_sharehead->lh_first; 535 if (r->r_flags & RF_FIRSTSHARE) { 536 s->r_flags |= RF_FIRSTSHARE; 537 CIRCLEQ_INSERT_BEFORE(&rm->rm_list, r, s, r_link); 538 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 539 } 540 541 /* 542 * Make sure that the sharing list goes away completely 543 * if the resource is no longer being shared at all. 544 */ 545 if (s->r_sharelink.le_next == 0) { 546 free(s->r_sharehead, M_RMAN); 547 s->r_sharehead = 0; 548 s->r_flags &= ~RF_FIRSTSHARE; 549 } 550 goto out; 551 } 552 553 /* 554 * Look at the adjacent resources in the list and see if our 555 * segment can be merged with any of them. 556 */ 557 s = r->r_link.cqe_prev; 558 t = r->r_link.cqe_next; 559 560 if (s != (void *)&rm->rm_list && (s->r_flags & RF_ALLOCATED) == 0 561 && t != (void *)&rm->rm_list && (t->r_flags & RF_ALLOCATED) == 0) { 562 /* 563 * Merge all three segments. 564 */ 565 s->r_end = t->r_end; 566 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 567 CIRCLEQ_REMOVE(&rm->rm_list, t, r_link); 568 free(t, M_RMAN); 569 } else if (s != (void *)&rm->rm_list 570 && (s->r_flags & RF_ALLOCATED) == 0) { 571 /* 572 * Merge previous segment with ours. 573 */ 574 s->r_end = r->r_end; 575 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 576 } else if (t != (void *)&rm->rm_list 577 && (t->r_flags & RF_ALLOCATED) == 0) { 578 /* 579 * Merge next segment with ours. 580 */ 581 t->r_start = r->r_start; 582 CIRCLEQ_REMOVE(&rm->rm_list, r, r_link); 583 } else { 584 /* 585 * At this point, we know there is nothing we 586 * can potentially merge with, because on each 587 * side, there is either nothing there or what is 588 * there is still allocated. In that case, we don't 589 * want to remove r from the list; we simply want to 590 * change it to an unallocated region and return 591 * without freeing anything. 592 */ 593 r->r_flags &= ~RF_ALLOCATED; 594 return 0; 595 } 596 597out: 598 free(r, M_RMAN); 599 return 0; 600} 601 602int 603rman_release_resource(struct resource *r) 604{ 605 int rv; 606 struct rman *rm = r->r_rm; 607 608 simple_lock(rm->rm_slock); 609 rv = int_rman_release_resource(rm, r); 610 simple_unlock(rm->rm_slock); 611 return (rv); 612}
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