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/param.h>
30 #include <sys/kernel.h>
31 #include <sys/systm.h>
32 #include <sys/sysctl.h>
33 #include <sys/errno.h>
35 #include <sys/malloc.h>
37 #include <sys/mutex.h>
38 #include <sys/rmlock.h>
40 #include <sys/queue.h>
44 /* OSD (Object Specific Data) */
53 struct sx osd_module_lock;
54 struct rmlock osd_object_lock;
55 struct mtx osd_list_lock;
56 LIST_HEAD(, osd) osd_list; /* (l) */
57 osd_destructor_t *osd_destructors; /* (o) */
58 osd_method_t *osd_methods; /* (m) */
59 u_int osd_ntslots; /* (m) */
60 const u_int osd_nmethods;
63 static MALLOC_DEFINE(M_OSD, "osd", "Object Specific Data");
65 static int osd_debug = 0;
66 SYSCTL_INT(_debug, OID_AUTO, osd, CTLFLAG_RWTUN, &osd_debug, 0, "OSD debug level");
68 #define OSD_DEBUG(...) do { \
70 printf("OSD (%s:%u): ", __func__, __LINE__); \
71 printf(__VA_ARGS__); \
76 static void do_osd_del(u_int type, struct osd *osd, u_int slot,
80 * List of objects with OSD.
82 struct osd_master osdm[OSD_LAST + 1] = {
83 [OSD_JAIL] = { .osd_nmethods = PR_MAXMETHOD },
87 osd_default_destructor(void *value __unused)
93 osd_register(u_int type, osd_destructor_t destructor, osd_method_t *methods)
98 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
101 * If no destructor is given, use default one. We need to use some
102 * destructor, because NULL destructor means unused slot.
104 if (destructor == NULL)
105 destructor = osd_default_destructor;
107 sx_xlock(&osdm[type].osd_module_lock);
109 * First, we try to find unused slot.
111 for (i = 0; i < osdm[type].osd_ntslots; i++) {
112 if (osdm[type].osd_destructors[i] == NULL) {
113 OSD_DEBUG("Unused slot found (type=%u, slot=%u).",
119 * If no unused slot was found, allocate one.
121 if (i == osdm[type].osd_ntslots) {
122 osdm[type].osd_ntslots++;
123 if (osdm[type].osd_nmethods != 0)
124 osdm[type].osd_methods = realloc(osdm[type].osd_methods,
125 sizeof(osd_method_t) * osdm[type].osd_ntslots *
126 osdm[type].osd_nmethods, M_OSD, M_WAITOK);
127 newptr = malloc(sizeof(osd_destructor_t) *
128 osdm[type].osd_ntslots, M_OSD, M_WAITOK);
129 rm_wlock(&osdm[type].osd_object_lock);
130 bcopy(osdm[type].osd_destructors, newptr,
131 sizeof(osd_destructor_t) * i);
132 free(osdm[type].osd_destructors, M_OSD);
133 osdm[type].osd_destructors = newptr;
134 rm_wunlock(&osdm[type].osd_object_lock);
135 OSD_DEBUG("New slot allocated (type=%u, slot=%u).",
139 osdm[type].osd_destructors[i] = destructor;
140 if (osdm[type].osd_nmethods != 0) {
141 for (m = 0; m < osdm[type].osd_nmethods; m++)
142 osdm[type].osd_methods[i * osdm[type].osd_nmethods + m]
143 = methods != NULL ? methods[m] : NULL;
145 sx_xunlock(&osdm[type].osd_module_lock);
150 osd_deregister(u_int type, u_int slot)
152 struct osd *osd, *tosd;
154 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
155 KASSERT(slot > 0, ("Invalid slot."));
157 sx_xlock(&osdm[type].osd_module_lock);
158 rm_wlock(&osdm[type].osd_object_lock);
159 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
162 * Free all OSD for the given slot.
164 mtx_lock(&osdm[type].osd_list_lock);
165 LIST_FOREACH_SAFE(osd, &osdm[type].osd_list, osd_next, tosd)
166 do_osd_del(type, osd, slot, 1);
167 mtx_unlock(&osdm[type].osd_list_lock);
170 * Set destructor to NULL to free the slot. We don't bother actually
171 * freeing any memory here because we'll gracefully reuse any freed
172 * slots, and reallocating the arrays as a smaller chunk of memory isn't
173 * actually guaranteed to succeed. As such, we'll err on the side of
174 * caution and just leave it be since these are generally modestly sized
177 osdm[type].osd_destructors[slot - 1] = NULL;
178 OSD_DEBUG("Slot deregistration (type=%u, slot=%u).", type, slot);
180 rm_wunlock(&osdm[type].osd_object_lock);
181 sx_xunlock(&osdm[type].osd_module_lock);
185 osd_set(u_int type, struct osd *osd, u_int slot, void *value)
188 return (osd_set_reserved(type, osd, slot, NULL, value));
192 osd_reserve(u_int slot)
195 KASSERT(slot > 0, ("Invalid slot."));
197 OSD_DEBUG("Reserving slot array (slot=%u).", slot);
198 return (malloc(sizeof(void *) * slot, M_OSD, M_WAITOK | M_ZERO));
202 osd_set_reserved(u_int type, struct osd *osd, u_int slot, void **rsv,
205 struct rm_priotracker tracker;
207 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
208 KASSERT(slot > 0, ("Invalid slot."));
210 rm_rlock(&osdm[type].osd_object_lock, &tracker);
211 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
213 if (slot > osd->osd_nslots) {
218 "Not allocating null slot (type=%u, slot=%u).",
220 rm_runlock(&osdm[type].osd_object_lock, &tracker);
222 osd_free_reserved(rsv);
227 * Too few slots allocated here, so we need to extend or create
232 * Use the reserve passed in (assumed to be
236 if (osd->osd_nslots != 0) {
237 memcpy(newptr, osd->osd_slots,
238 sizeof(void *) * osd->osd_nslots);
239 free(osd->osd_slots, M_OSD);
242 newptr = realloc(osd->osd_slots, sizeof(void *) * slot,
243 M_OSD, M_NOWAIT | M_ZERO);
244 if (newptr == NULL) {
245 rm_runlock(&osdm[type].osd_object_lock,
250 if (osd->osd_nslots == 0) {
252 * First OSD for this object, so we need to put it
255 mtx_lock(&osdm[type].osd_list_lock);
256 LIST_INSERT_HEAD(&osdm[type].osd_list, osd, osd_next);
257 mtx_unlock(&osdm[type].osd_list_lock);
258 OSD_DEBUG("Setting first slot (type=%u).", type);
260 OSD_DEBUG("Growing slots array (type=%u).", type);
261 osd->osd_slots = newptr;
262 osd->osd_nslots = slot;
264 osd_free_reserved(rsv);
265 OSD_DEBUG("Setting slot value (type=%u, slot=%u, value=%p).", type,
267 osd->osd_slots[slot - 1] = value;
268 rm_runlock(&osdm[type].osd_object_lock, &tracker);
273 osd_free_reserved(void **rsv)
276 OSD_DEBUG("Discarding reserved slot array.");
281 osd_get(u_int type, struct osd *osd, u_int slot)
283 struct rm_priotracker tracker;
286 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
287 KASSERT(slot > 0, ("Invalid slot."));
289 rm_rlock(&osdm[type].osd_object_lock, &tracker);
290 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
292 if (slot > osd->osd_nslots) {
294 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
296 value = osd->osd_slots[slot - 1];
297 OSD_DEBUG("Returning slot value (type=%u, slot=%u, value=%p).",
300 rm_runlock(&osdm[type].osd_object_lock, &tracker);
305 osd_del(u_int type, struct osd *osd, u_int slot)
307 struct rm_priotracker tracker;
309 rm_rlock(&osdm[type].osd_object_lock, &tracker);
310 do_osd_del(type, osd, slot, 0);
311 rm_runlock(&osdm[type].osd_object_lock, &tracker);
315 do_osd_del(u_int type, struct osd *osd, u_int slot, int list_locked)
319 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
320 KASSERT(slot > 0, ("Invalid slot."));
321 KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
323 OSD_DEBUG("Deleting slot (type=%u, slot=%u).", type, slot);
325 if (slot > osd->osd_nslots) {
326 OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot);
329 if (osd->osd_slots[slot - 1] != NULL) {
330 osdm[type].osd_destructors[slot - 1](osd->osd_slots[slot - 1]);
331 osd->osd_slots[slot - 1] = NULL;
333 for (i = osd->osd_nslots - 1; i >= 0; i--) {
334 if (osd->osd_slots[i] != NULL) {
335 OSD_DEBUG("Slot still has a value (type=%u, slot=%u).",
341 /* No values left for this object. */
342 OSD_DEBUG("No more slots left (type=%u).", type);
344 mtx_lock(&osdm[type].osd_list_lock);
345 LIST_REMOVE(osd, osd_next);
347 mtx_unlock(&osdm[type].osd_list_lock);
348 free(osd->osd_slots, M_OSD);
349 osd->osd_slots = NULL;
351 } else if (slot == osd->osd_nslots) {
352 /* This was the last slot. */
353 osd->osd_slots = realloc(osd->osd_slots,
354 sizeof(void *) * (i + 1), M_OSD, M_NOWAIT | M_ZERO);
356 * We always reallocate to smaller size, so we assume it will
359 KASSERT(osd->osd_slots != NULL, ("realloc() failed"));
360 osd->osd_nslots = i + 1;
361 OSD_DEBUG("Reducing slots array to %u (type=%u).",
362 osd->osd_nslots, type);
367 osd_call(u_int type, u_int method, void *obj, void *data)
369 osd_method_t methodfun;
372 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
373 KASSERT(method < osdm[type].osd_nmethods, ("Invalid method."));
376 * Call this method for every slot that defines it, stopping if an
377 * error is encountered.
380 sx_slock(&osdm[type].osd_module_lock);
381 for (i = 0; i < osdm[type].osd_ntslots; i++) {
382 /* Hole in the slot map; avoid dereferencing. */
383 if (osdm[type].osd_destructors[i] == NULL)
385 methodfun = osdm[type].osd_methods[i * osdm[type].osd_nmethods +
387 if (methodfun != NULL && (error = methodfun(obj, data)) != 0)
390 sx_sunlock(&osdm[type].osd_module_lock);
395 osd_exit(u_int type, struct osd *osd)
397 struct rm_priotracker tracker;
400 KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
402 if (osd->osd_nslots == 0) {
403 KASSERT(osd->osd_slots == NULL, ("Non-null osd_slots."));
404 /* No OSD attached, just leave. */
408 rm_rlock(&osdm[type].osd_object_lock, &tracker);
409 for (i = 1; i <= osd->osd_nslots; i++) {
410 if (osdm[type].osd_destructors[i - 1] != NULL)
411 do_osd_del(type, osd, i, 0);
413 OSD_DEBUG("Unused slot (type=%u, slot=%u).", type, i);
415 rm_runlock(&osdm[type].osd_object_lock, &tracker);
416 OSD_DEBUG("Object exit (type=%u).", type);
420 osd_init(void *arg __unused)
424 for (i = OSD_FIRST; i <= OSD_LAST; i++) {
425 sx_init(&osdm[i].osd_module_lock, "osd_module");
426 rm_init(&osdm[i].osd_object_lock, "osd_object");
427 mtx_init(&osdm[i].osd_list_lock, "osd_list", NULL, MTX_DEF);
428 LIST_INIT(&osdm[i].osd_list);
429 osdm[i].osd_destructors = NULL;
430 osdm[i].osd_ntslots = 0;
431 osdm[i].osd_methods = NULL;
434 SYSINIT(osd, SI_SUB_LOCK, SI_ORDER_ANY, osd_init, NULL);