2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
30 #include <sys/param.h>
31 #include <sys/kernel.h>
32 #include <sys/systm.h>
33 #include <sys/sysctl.h>
34 #include <sys/errno.h>
36 #include <sys/malloc.h>
38 #include <sys/mutex.h>
39 #include <sys/rmlock.h>
41 #include <sys/queue.h>
45 /* OSD (Object Specific Data) */
54 struct sx osd_module_lock;
55 struct rmlock osd_object_lock;
56 struct mtx osd_list_lock;
57 LIST_HEAD(, osd) osd_list; /* (l) */
58 osd_destructor_t *osd_destructors; /* (o) */
59 osd_method_t *osd_methods; /* (m) */
60 u_int osd_ntslots; /* (m) */
61 const u_int osd_nmethods;
64 static MALLOC_DEFINE(M_OSD, "osd", "Object Specific Data");
66 static int osd_debug = 0;
67 SYSCTL_INT(_debug, OID_AUTO, osd, CTLFLAG_RWTUN, &osd_debug, 0, "OSD debug level");
69 #define OSD_DEBUG(...) do { \
71 printf("OSD (%s:%u): ", __func__, __LINE__); \
72 printf(__VA_ARGS__); \
77 static void do_osd_del(u_int type, struct osd *osd, u_int slot,
81 * List of objects with OSD.
83 struct osd_master osdm[OSD_LAST + 1] = {
84 [OSD_JAIL] = { .osd_nmethods = PR_MAXMETHOD },
88 osd_default_destructor(void *value __unused)
94 osd_register(u_int type, osd_destructor_t destructor, osd_method_t *methods)
99 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
102 * If no destructor is given, use default one. We need to use some
103 * destructor, because NULL destructor means unused slot.
105 if (destructor == NULL)
106 destructor = osd_default_destructor;
108 sx_xlock(&osdm[type].osd_module_lock);
110 * First, we try to find unused slot.
112 for (i = 0; i < osdm[type].osd_ntslots; i++) {
113 if (osdm[type].osd_destructors[i] == NULL) {
114 OSD_DEBUG("Unused slot found (type=%u, slot=%u).",
120 * If no unused slot was found, allocate one.
122 if (i == osdm[type].osd_ntslots) {
123 osdm[type].osd_ntslots++;
124 if (osdm[type].osd_nmethods != 0)
125 osdm[type].osd_methods = realloc(osdm[type].osd_methods,
126 sizeof(osd_method_t) * osdm[type].osd_ntslots *
127 osdm[type].osd_nmethods, M_OSD, M_WAITOK);
128 newptr = malloc(sizeof(osd_destructor_t) *
129 osdm[type].osd_ntslots, M_OSD, M_WAITOK);
130 rm_wlock(&osdm[type].osd_object_lock);
131 bcopy(osdm[type].osd_destructors, newptr,
132 sizeof(osd_destructor_t) * i);
133 free(osdm[type].osd_destructors, M_OSD);
134 osdm[type].osd_destructors = newptr;
135 rm_wunlock(&osdm[type].osd_object_lock);
136 OSD_DEBUG("New slot allocated (type=%u, slot=%u).",
140 osdm[type].osd_destructors[i] = destructor;
141 if (osdm[type].osd_nmethods != 0) {
142 for (m = 0; m < osdm[type].osd_nmethods; m++)
143 osdm[type].osd_methods[i * osdm[type].osd_nmethods + m]
144 = methods != NULL ? methods[m] : NULL;
146 sx_xunlock(&osdm[type].osd_module_lock);
151 osd_deregister(u_int type, u_int slot)
153 struct osd *osd, *tosd;
155 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
156 KASSERT(slot > 0, ("Invalid slot."));
158 sx_xlock(&osdm[type].osd_module_lock);
159 rm_wlock(&osdm[type].osd_object_lock);
160 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
163 * Free all OSD for the given slot.
165 mtx_lock(&osdm[type].osd_list_lock);
166 LIST_FOREACH_SAFE(osd, &osdm[type].osd_list, osd_next, tosd)
167 do_osd_del(type, osd, slot, 1);
168 mtx_unlock(&osdm[type].osd_list_lock);
171 * Set destructor to NULL to free the slot. We don't bother actually
172 * freeing any memory here because we'll gracefully reuse any freed
173 * slots, and reallocating the arrays as a smaller chunk of memory isn't
174 * actually guaranteed to succeed. As such, we'll err on the side of
175 * caution and just leave it be since these are generally modestly sized
178 osdm[type].osd_destructors[slot - 1] = NULL;
179 OSD_DEBUG("Slot deregistration (type=%u, slot=%u).", type, slot);
181 rm_wunlock(&osdm[type].osd_object_lock);
182 sx_xunlock(&osdm[type].osd_module_lock);
186 osd_set(u_int type, struct osd *osd, u_int slot, void *value)
189 return (osd_set_reserved(type, osd, slot, NULL, value));
193 osd_reserve(u_int slot)
196 KASSERT(slot > 0, ("Invalid slot."));
198 OSD_DEBUG("Reserving slot array (slot=%u).", slot);
199 return (malloc(sizeof(void *) * slot, M_OSD, M_WAITOK | M_ZERO));
203 osd_set_reserved(u_int type, struct osd *osd, u_int slot, void **rsv,
206 struct rm_priotracker tracker;
208 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
209 KASSERT(slot > 0, ("Invalid slot."));
211 rm_rlock(&osdm[type].osd_object_lock, &tracker);
212 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
214 if (slot > osd->osd_nslots) {
219 "Not allocating null slot (type=%u, slot=%u).",
221 rm_runlock(&osdm[type].osd_object_lock, &tracker);
223 osd_free_reserved(rsv);
228 * Too few slots allocated here, so we need to extend or create
233 * Use the reserve passed in (assumed to be
237 if (osd->osd_nslots != 0) {
238 memcpy(newptr, osd->osd_slots,
239 sizeof(void *) * osd->osd_nslots);
240 free(osd->osd_slots, M_OSD);
243 newptr = realloc(osd->osd_slots, sizeof(void *) * slot,
244 M_OSD, M_NOWAIT | M_ZERO);
245 if (newptr == NULL) {
246 rm_runlock(&osdm[type].osd_object_lock,
251 if (osd->osd_nslots == 0) {
253 * First OSD for this object, so we need to put it
256 mtx_lock(&osdm[type].osd_list_lock);
257 LIST_INSERT_HEAD(&osdm[type].osd_list, osd, osd_next);
258 mtx_unlock(&osdm[type].osd_list_lock);
259 OSD_DEBUG("Setting first slot (type=%u).", type);
261 OSD_DEBUG("Growing slots array (type=%u).", type);
262 osd->osd_slots = newptr;
263 osd->osd_nslots = slot;
265 osd_free_reserved(rsv);
266 OSD_DEBUG("Setting slot value (type=%u, slot=%u, value=%p).", type,
268 osd->osd_slots[slot - 1] = value;
269 rm_runlock(&osdm[type].osd_object_lock, &tracker);
274 osd_free_reserved(void **rsv)
277 OSD_DEBUG("Discarding reserved slot array.");
282 osd_get(u_int type, struct osd *osd, u_int slot)
284 struct rm_priotracker tracker;
287 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
288 KASSERT(slot > 0, ("Invalid slot."));
290 rm_rlock(&osdm[type].osd_object_lock, &tracker);
291 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
293 if (slot > osd->osd_nslots) {
295 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
297 value = osd->osd_slots[slot - 1];
298 OSD_DEBUG("Returning slot value (type=%u, slot=%u, value=%p).",
301 rm_runlock(&osdm[type].osd_object_lock, &tracker);
306 osd_del(u_int type, struct osd *osd, u_int slot)
308 struct rm_priotracker tracker;
310 rm_rlock(&osdm[type].osd_object_lock, &tracker);
311 do_osd_del(type, osd, slot, 0);
312 rm_runlock(&osdm[type].osd_object_lock, &tracker);
316 do_osd_del(u_int type, struct osd *osd, u_int slot, int list_locked)
320 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
321 KASSERT(slot > 0, ("Invalid slot."));
322 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
324 OSD_DEBUG("Deleting slot (type=%u, slot=%u).", type, slot);
326 if (slot > osd->osd_nslots) {
327 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
330 if (osd->osd_slots[slot - 1] != NULL) {
331 osdm[type].osd_destructors[slot - 1](osd->osd_slots[slot - 1]);
332 osd->osd_slots[slot - 1] = NULL;
334 for (i = osd->osd_nslots - 1; i >= 0; i--) {
335 if (osd->osd_slots[i] != NULL) {
336 OSD_DEBUG("Slot still has a value (type=%u, slot=%u).",
342 /* No values left for this object. */
343 OSD_DEBUG("No more slots left (type=%u).", type);
345 mtx_lock(&osdm[type].osd_list_lock);
346 LIST_REMOVE(osd, osd_next);
348 mtx_unlock(&osdm[type].osd_list_lock);
349 free(osd->osd_slots, M_OSD);
350 osd->osd_slots = NULL;
352 } else if (slot == osd->osd_nslots) {
353 /* This was the last slot. */
354 osd->osd_slots = realloc(osd->osd_slots,
355 sizeof(void *) * (i + 1), M_OSD, M_NOWAIT | M_ZERO);
357 * We always reallocate to smaller size, so we assume it will
360 KASSERT(osd->osd_slots != NULL, ("realloc() failed"));
361 osd->osd_nslots = i + 1;
362 OSD_DEBUG("Reducing slots array to %u (type=%u).",
363 osd->osd_nslots, type);
368 osd_call(u_int type, u_int method, void *obj, void *data)
370 osd_method_t methodfun;
373 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
374 KASSERT(method < osdm[type].osd_nmethods, ("Invalid method."));
377 * Call this method for every slot that defines it, stopping if an
378 * error is encountered.
381 sx_slock(&osdm[type].osd_module_lock);
382 for (i = 0; i < osdm[type].osd_ntslots; i++) {
383 /* Hole in the slot map; avoid dereferencing. */
384 if (osdm[type].osd_destructors[i] == NULL)
386 methodfun = osdm[type].osd_methods[i * osdm[type].osd_nmethods +
388 if (methodfun != NULL && (error = methodfun(obj, data)) != 0)
391 sx_sunlock(&osdm[type].osd_module_lock);
396 osd_exit(u_int type, struct osd *osd)
398 struct rm_priotracker tracker;
401 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
403 if (osd->osd_nslots == 0) {
404 KASSERT(osd->osd_slots == NULL, ("Non-null osd_slots."));
405 /* No OSD attached, just leave. */
409 rm_rlock(&osdm[type].osd_object_lock, &tracker);
410 for (i = 1; i <= osd->osd_nslots; i++) {
411 if (osdm[type].osd_destructors[i - 1] != NULL)
412 do_osd_del(type, osd, i, 0);
414 OSD_DEBUG("Unused slot (type=%u, slot=%u).", type, i);
416 rm_runlock(&osdm[type].osd_object_lock, &tracker);
417 OSD_DEBUG("Object exit (type=%u).", type);
421 osd_init(void *arg __unused)
425 for (i = OSD_FIRST; i <= OSD_LAST; i++) {
426 sx_init(&osdm[i].osd_module_lock, "osd_module");
427 rm_init(&osdm[i].osd_object_lock, "osd_object");
428 mtx_init(&osdm[i].osd_list_lock, "osd_list", NULL, MTX_DEF);
429 LIST_INIT(&osdm[i].osd_list);
430 osdm[i].osd_destructors = NULL;
431 osdm[i].osd_ntslots = 0;
432 osdm[i].osd_methods = NULL;
435 SYSINIT(osd, SI_SUB_LOCK, SI_ORDER_ANY, osd_init, NULL);