2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 __FBSDID("$FreeBSD$");
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/systm.h>
35 #include <sys/sysctl.h>
36 #include <sys/errno.h>
38 #include <sys/malloc.h>
40 #include <sys/mutex.h>
41 #include <sys/rmlock.h>
43 #include <sys/queue.h>
47 /* OSD (Object Specific Data) */
56 struct sx osd_module_lock;
57 struct rmlock osd_object_lock;
58 struct mtx osd_list_lock;
59 LIST_HEAD(, osd) osd_list; /* (l) */
60 osd_destructor_t *osd_destructors; /* (o) */
61 osd_method_t *osd_methods; /* (m) */
62 u_int osd_ntslots; /* (m) */
63 const u_int osd_nmethods;
66 static MALLOC_DEFINE(M_OSD, "osd", "Object Specific Data");
68 static int osd_debug = 0;
69 SYSCTL_INT(_debug, OID_AUTO, osd, CTLFLAG_RWTUN, &osd_debug, 0, "OSD debug level");
71 #define OSD_DEBUG(...) do { \
73 printf("OSD (%s:%u): ", __func__, __LINE__); \
74 printf(__VA_ARGS__); \
79 static void do_osd_del(u_int type, struct osd *osd, u_int slot,
83 * List of objects with OSD.
85 struct osd_master osdm[OSD_LAST + 1] = {
86 [OSD_JAIL] = { .osd_nmethods = PR_MAXMETHOD },
90 osd_default_destructor(void *value __unused)
96 osd_register(u_int type, osd_destructor_t destructor, osd_method_t *methods)
101 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
104 * If no destructor is given, use default one. We need to use some
105 * destructor, because NULL destructor means unused slot.
107 if (destructor == NULL)
108 destructor = osd_default_destructor;
110 sx_xlock(&osdm[type].osd_module_lock);
112 * First, we try to find unused slot.
114 for (i = 0; i < osdm[type].osd_ntslots; i++) {
115 if (osdm[type].osd_destructors[i] == NULL) {
116 OSD_DEBUG("Unused slot found (type=%u, slot=%u).",
122 * If no unused slot was found, allocate one.
124 if (i == osdm[type].osd_ntslots) {
125 osdm[type].osd_ntslots++;
126 if (osdm[type].osd_nmethods != 0)
127 osdm[type].osd_methods = realloc(osdm[type].osd_methods,
128 sizeof(osd_method_t) * osdm[type].osd_ntslots *
129 osdm[type].osd_nmethods, M_OSD, M_WAITOK);
130 newptr = malloc(sizeof(osd_destructor_t) *
131 osdm[type].osd_ntslots, M_OSD, M_WAITOK);
132 rm_wlock(&osdm[type].osd_object_lock);
133 bcopy(osdm[type].osd_destructors, newptr,
134 sizeof(osd_destructor_t) * i);
135 free(osdm[type].osd_destructors, M_OSD);
136 osdm[type].osd_destructors = newptr;
137 rm_wunlock(&osdm[type].osd_object_lock);
138 OSD_DEBUG("New slot allocated (type=%u, slot=%u).",
142 osdm[type].osd_destructors[i] = destructor;
143 if (osdm[type].osd_nmethods != 0) {
144 for (m = 0; m < osdm[type].osd_nmethods; m++)
145 osdm[type].osd_methods[i * osdm[type].osd_nmethods + m]
146 = methods != NULL ? methods[m] : NULL;
148 sx_xunlock(&osdm[type].osd_module_lock);
153 osd_deregister(u_int type, u_int slot)
155 struct osd *osd, *tosd;
157 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
158 KASSERT(slot > 0, ("Invalid slot."));
159 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
161 sx_xlock(&osdm[type].osd_module_lock);
162 rm_wlock(&osdm[type].osd_object_lock);
164 * Free all OSD for the given slot.
166 mtx_lock(&osdm[type].osd_list_lock);
167 LIST_FOREACH_SAFE(osd, &osdm[type].osd_list, osd_next, tosd)
168 do_osd_del(type, osd, slot, 1);
169 mtx_unlock(&osdm[type].osd_list_lock);
171 * Set destructor to NULL to free the slot.
173 osdm[type].osd_destructors[slot - 1] = NULL;
174 if (slot == osdm[type].osd_ntslots) {
175 osdm[type].osd_ntslots--;
176 osdm[type].osd_destructors = realloc(osdm[type].osd_destructors,
177 sizeof(osd_destructor_t) * osdm[type].osd_ntslots, M_OSD,
179 if (osdm[type].osd_nmethods != 0)
180 osdm[type].osd_methods = realloc(osdm[type].osd_methods,
181 sizeof(osd_method_t) * osdm[type].osd_ntslots *
182 osdm[type].osd_nmethods, M_OSD, M_NOWAIT | M_ZERO);
184 * We always reallocate to smaller size, so we assume it will
187 KASSERT(osdm[type].osd_destructors != NULL &&
188 (osdm[type].osd_nmethods == 0 ||
189 osdm[type].osd_methods != NULL), ("realloc() failed"));
190 OSD_DEBUG("Deregistration of the last slot (type=%u, slot=%u).",
193 OSD_DEBUG("Slot deregistration (type=%u, slot=%u).",
196 rm_wunlock(&osdm[type].osd_object_lock);
197 sx_xunlock(&osdm[type].osd_module_lock);
201 osd_set(u_int type, struct osd *osd, u_int slot, void *value)
204 return (osd_set_reserved(type, osd, slot, NULL, value));
208 osd_reserve(u_int slot)
211 KASSERT(slot > 0, ("Invalid slot."));
213 OSD_DEBUG("Reserving slot array (slot=%u).", slot);
214 return (malloc(sizeof(void *) * slot, M_OSD, M_WAITOK | M_ZERO));
218 osd_set_reserved(u_int type, struct osd *osd, u_int slot, void **rsv,
221 struct rm_priotracker tracker;
223 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
224 KASSERT(slot > 0, ("Invalid slot."));
225 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
227 rm_rlock(&osdm[type].osd_object_lock, &tracker);
228 if (slot > osd->osd_nslots) {
233 "Not allocating null slot (type=%u, slot=%u).",
235 rm_runlock(&osdm[type].osd_object_lock, &tracker);
237 osd_free_reserved(rsv);
242 * Too few slots allocated here, so we need to extend or create
247 * Use the reserve passed in (assumed to be
251 if (osd->osd_nslots != 0) {
252 memcpy(newptr, osd->osd_slots,
253 sizeof(void *) * osd->osd_nslots);
254 free(osd->osd_slots, M_OSD);
257 newptr = realloc(osd->osd_slots, sizeof(void *) * slot,
258 M_OSD, M_NOWAIT | M_ZERO);
259 if (newptr == NULL) {
260 rm_runlock(&osdm[type].osd_object_lock,
265 if (osd->osd_nslots == 0) {
267 * First OSD for this object, so we need to put it
270 mtx_lock(&osdm[type].osd_list_lock);
271 LIST_INSERT_HEAD(&osdm[type].osd_list, osd, osd_next);
272 mtx_unlock(&osdm[type].osd_list_lock);
273 OSD_DEBUG("Setting first slot (type=%u).", type);
275 OSD_DEBUG("Growing slots array (type=%u).", type);
276 osd->osd_slots = newptr;
277 osd->osd_nslots = slot;
279 osd_free_reserved(rsv);
280 OSD_DEBUG("Setting slot value (type=%u, slot=%u, value=%p).", type,
282 osd->osd_slots[slot - 1] = value;
283 rm_runlock(&osdm[type].osd_object_lock, &tracker);
288 osd_free_reserved(void **rsv)
291 OSD_DEBUG("Discarding reserved slot array.");
296 osd_get(u_int type, struct osd *osd, u_int slot)
298 struct rm_priotracker tracker;
301 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
302 KASSERT(slot > 0, ("Invalid slot."));
303 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
305 rm_rlock(&osdm[type].osd_object_lock, &tracker);
306 if (slot > osd->osd_nslots) {
308 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
310 value = osd->osd_slots[slot - 1];
311 OSD_DEBUG("Returning slot value (type=%u, slot=%u, value=%p).",
314 rm_runlock(&osdm[type].osd_object_lock, &tracker);
319 osd_del(u_int type, struct osd *osd, u_int slot)
321 struct rm_priotracker tracker;
323 rm_rlock(&osdm[type].osd_object_lock, &tracker);
324 do_osd_del(type, osd, slot, 0);
325 rm_runlock(&osdm[type].osd_object_lock, &tracker);
329 do_osd_del(u_int type, struct osd *osd, u_int slot, int list_locked)
333 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
334 KASSERT(slot > 0, ("Invalid slot."));
335 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
337 OSD_DEBUG("Deleting slot (type=%u, slot=%u).", type, slot);
339 if (slot > osd->osd_nslots) {
340 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
343 if (osd->osd_slots[slot - 1] != NULL) {
344 osdm[type].osd_destructors[slot - 1](osd->osd_slots[slot - 1]);
345 osd->osd_slots[slot - 1] = NULL;
347 for (i = osd->osd_nslots - 1; i >= 0; i--) {
348 if (osd->osd_slots[i] != NULL) {
349 OSD_DEBUG("Slot still has a value (type=%u, slot=%u).",
355 /* No values left for this object. */
356 OSD_DEBUG("No more slots left (type=%u).", type);
358 mtx_lock(&osdm[type].osd_list_lock);
359 LIST_REMOVE(osd, osd_next);
361 mtx_unlock(&osdm[type].osd_list_lock);
362 free(osd->osd_slots, M_OSD);
363 osd->osd_slots = NULL;
365 } else if (slot == osd->osd_nslots) {
366 /* This was the last slot. */
367 osd->osd_slots = realloc(osd->osd_slots,
368 sizeof(void *) * (i + 1), M_OSD, M_NOWAIT | M_ZERO);
370 * We always reallocate to smaller size, so we assume it will
373 KASSERT(osd->osd_slots != NULL, ("realloc() failed"));
374 osd->osd_nslots = i + 1;
375 OSD_DEBUG("Reducing slots array to %u (type=%u).",
376 osd->osd_nslots, type);
381 osd_call(u_int type, u_int method, void *obj, void *data)
383 osd_method_t methodfun;
386 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
387 KASSERT(method < osdm[type].osd_nmethods, ("Invalid method."));
390 * Call this method for every slot that defines it, stopping if an
391 * error is encountered.
394 sx_slock(&osdm[type].osd_module_lock);
395 for (i = 0; i < osdm[type].osd_ntslots; i++) {
396 methodfun = osdm[type].osd_methods[i * osdm[type].osd_nmethods +
398 if (methodfun != NULL && (error = methodfun(obj, data)) != 0)
401 sx_sunlock(&osdm[type].osd_module_lock);
406 osd_exit(u_int type, struct osd *osd)
408 struct rm_priotracker tracker;
411 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
413 if (osd->osd_nslots == 0) {
414 KASSERT(osd->osd_slots == NULL, ("Non-null osd_slots."));
415 /* No OSD attached, just leave. */
419 rm_rlock(&osdm[type].osd_object_lock, &tracker);
420 for (i = 1; i <= osd->osd_nslots; i++) {
421 if (osdm[type].osd_destructors[i - 1] != NULL)
422 do_osd_del(type, osd, i, 0);
424 OSD_DEBUG("Unused slot (type=%u, slot=%u).", type, i);
426 rm_runlock(&osdm[type].osd_object_lock, &tracker);
427 OSD_DEBUG("Object exit (type=%u).", type);
431 osd_init(void *arg __unused)
435 for (i = OSD_FIRST; i <= OSD_LAST; i++) {
436 sx_init(&osdm[i].osd_module_lock, "osd_module");
437 rm_init(&osdm[i].osd_object_lock, "osd_object");
438 mtx_init(&osdm[i].osd_list_lock, "osd_list", NULL, MTX_DEF);
439 LIST_INIT(&osdm[i].osd_list);
440 osdm[i].osd_destructors = NULL;
441 osdm[i].osd_ntslots = 0;
442 osdm[i].osd_methods = NULL;
445 SYSINIT(osd, SI_SUB_LOCK, SI_ORDER_ANY, osd_init, NULL);