/*- * Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org> * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <sys/cdefs.h> __FBSDID("$FreeBSD$"); #include <sys/param.h> #include <sys/kernel.h> #include <sys/systm.h> #include <sys/sysctl.h> #include <sys/errno.h> #include <sys/jail.h> #include <sys/malloc.h> #include <sys/lock.h> #include <sys/mutex.h> #include <sys/rmlock.h> #include <sys/sx.h> #include <sys/queue.h> #include <sys/proc.h> #include <sys/osd.h> /* OSD (Object Specific Data) */ static MALLOC_DEFINE(M_OSD, "osd", "Object Specific Data"); static int osd_debug = 0; TUNABLE_INT("debug.osd", &osd_debug); SYSCTL_INT(_debug, OID_AUTO, osd, CTLFLAG_RW, &osd_debug, 0, "OSD debug level"); #define OSD_DEBUG(...) do { \ if (osd_debug) { \ printf("OSD (%s:%u): ", __func__, __LINE__); \ printf(__VA_ARGS__); \ printf("\n"); \ } \ } while (0) static void do_osd_del(u_int type, struct osd *osd, u_int slot, int list_locked); /* * Lists of objects with OSD. * * Lock key: * (m) osd_module_lock * (o) osd_object_lock * (l) osd_list_lock */ static LIST_HEAD(, osd) osd_list[OSD_LAST + 1]; /* (m) */ static osd_method_t *osd_methods[OSD_LAST + 1]; /* (m) */ static u_int osd_nslots[OSD_LAST + 1]; /* (m) */ static osd_destructor_t *osd_destructors[OSD_LAST + 1]; /* (o) */ static const u_int osd_nmethods[OSD_LAST + 1] = { [OSD_JAIL] = PR_MAXMETHOD, }; static struct sx osd_module_lock[OSD_LAST + 1]; static struct rmlock osd_object_lock[OSD_LAST + 1]; static struct mtx osd_list_lock[OSD_LAST + 1]; static void osd_default_destructor(void *value __unused) { /* Do nothing. */ } int osd_register(u_int type, osd_destructor_t destructor, osd_method_t *methods) { void *newptr; u_int i, m; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); /* * If no destructor is given, use default one. We need to use some * destructor, because NULL destructor means unused slot. */ if (destructor == NULL) destructor = osd_default_destructor; sx_xlock(&osd_module_lock[type]); /* * First, we try to find unused slot. */ for (i = 0; i < osd_nslots[type]; i++) { if (osd_destructors[type][i] == NULL) { OSD_DEBUG("Unused slot found (type=%u, slot=%u).", type, i); break; } } /* * If no unused slot was found, allocate one. */ if (i == osd_nslots[type]) { osd_nslots[type]++; if (osd_nmethods[type] != 0) osd_methods[type] = realloc(osd_methods[type], sizeof(osd_method_t) * osd_nslots[type] * osd_nmethods[type], M_OSD, M_WAITOK); newptr = malloc(sizeof(osd_destructor_t) * osd_nslots[type], M_OSD, M_WAITOK); rm_wlock(&osd_object_lock[type]); bcopy(osd_destructors[type], newptr, sizeof(osd_destructor_t) * i); free(osd_destructors[type], M_OSD); osd_destructors[type] = newptr; rm_wunlock(&osd_object_lock[type]); OSD_DEBUG("New slot allocated (type=%u, slot=%u).", type, i + 1); } osd_destructors[type][i] = destructor; if (osd_nmethods[type] != 0) { for (m = 0; m < osd_nmethods[type]; m++) osd_methods[type][i * osd_nmethods[type] + m] = methods != NULL ? methods[m] : NULL; } sx_xunlock(&osd_module_lock[type]); return (i + 1); } void osd_deregister(u_int type, u_int slot) { struct osd *osd, *tosd; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); KASSERT(slot > 0, ("Invalid slot.")); KASSERT(osd_destructors[type][slot - 1] != NULL, ("Unused slot.")); sx_xlock(&osd_module_lock[type]); rm_wlock(&osd_object_lock[type]); /* * Free all OSD for the given slot. */ mtx_lock(&osd_list_lock[type]); LIST_FOREACH_SAFE(osd, &osd_list[type], osd_next, tosd) do_osd_del(type, osd, slot, 1); mtx_unlock(&osd_list_lock[type]); /* * Set destructor to NULL to free the slot. */ osd_destructors[type][slot - 1] = NULL; if (slot == osd_nslots[type]) { osd_nslots[type]--; osd_destructors[type] = realloc(osd_destructors[type], sizeof(osd_destructor_t) * osd_nslots[type], M_OSD, M_NOWAIT | M_ZERO); if (osd_nmethods[type] != 0) osd_methods[type] = realloc(osd_methods[type], sizeof(osd_method_t) * osd_nslots[type] * osd_nmethods[type], M_OSD, M_NOWAIT | M_ZERO); /* * We always reallocate to smaller size, so we assume it will * always succeed. */ KASSERT(osd_destructors[type] != NULL && (osd_nmethods[type] == 0 || osd_methods[type] != NULL), ("realloc() failed")); OSD_DEBUG("Deregistration of the last slot (type=%u, slot=%u).", type, slot); } else { OSD_DEBUG("Slot deregistration (type=%u, slot=%u).", type, slot); } rm_wunlock(&osd_object_lock[type]); sx_xunlock(&osd_module_lock[type]); } int osd_set(u_int type, struct osd *osd, u_int slot, void *value) { struct rm_priotracker tracker; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); KASSERT(slot > 0, ("Invalid slot.")); KASSERT(osd_destructors[type][slot - 1] != NULL, ("Unused slot.")); rm_rlock(&osd_object_lock[type], &tracker); if (slot > osd->osd_nslots) { if (value == NULL) { OSD_DEBUG( "Not allocating null slot (type=%u, slot=%u).", type, slot); rm_runlock(&osd_object_lock[type], &tracker); return (0); } else if (osd->osd_nslots == 0) { /* * First OSD for this object, so we need to allocate * space and put it onto the list. */ osd->osd_slots = malloc(sizeof(void *) * slot, M_OSD, M_NOWAIT | M_ZERO); if (osd->osd_slots == NULL) { rm_runlock(&osd_object_lock[type], &tracker); return (ENOMEM); } osd->osd_nslots = slot; mtx_lock(&osd_list_lock[type]); LIST_INSERT_HEAD(&osd_list[type], osd, osd_next); mtx_unlock(&osd_list_lock[type]); OSD_DEBUG("Setting first slot (type=%u).", type); } else { void *newptr; /* * Too few slots allocated here, needs to extend * the array. */ newptr = realloc(osd->osd_slots, sizeof(void *) * slot, M_OSD, M_NOWAIT | M_ZERO); if (newptr == NULL) { rm_runlock(&osd_object_lock[type], &tracker); return (ENOMEM); } osd->osd_slots = newptr; osd->osd_nslots = slot; OSD_DEBUG("Growing slots array (type=%u).", type); } } OSD_DEBUG("Setting slot value (type=%u, slot=%u, value=%p).", type, slot, value); osd->osd_slots[slot - 1] = value; rm_runlock(&osd_object_lock[type], &tracker); return (0); } void * osd_get(u_int type, struct osd *osd, u_int slot) { struct rm_priotracker tracker; void *value; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); KASSERT(slot > 0, ("Invalid slot.")); KASSERT(osd_destructors[type][slot - 1] != NULL, ("Unused slot.")); rm_rlock(&osd_object_lock[type], &tracker); if (slot > osd->osd_nslots) { value = NULL; OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot); } else { value = osd->osd_slots[slot - 1]; OSD_DEBUG("Returning slot value (type=%u, slot=%u, value=%p).", type, slot, value); } rm_runlock(&osd_object_lock[type], &tracker); return (value); } void osd_del(u_int type, struct osd *osd, u_int slot) { struct rm_priotracker tracker; rm_rlock(&osd_object_lock[type], &tracker); do_osd_del(type, osd, slot, 0); rm_runlock(&osd_object_lock[type], &tracker); } static void do_osd_del(u_int type, struct osd *osd, u_int slot, int list_locked) { int i; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); KASSERT(slot > 0, ("Invalid slot.")); KASSERT(osd_destructors[type][slot - 1] != NULL, ("Unused slot.")); OSD_DEBUG("Deleting slot (type=%u, slot=%u).", type, slot); if (slot > osd->osd_nslots) { OSD_DEBUG("Slot doesn't exist (type=%u, slot=%u).", type, slot); return; } if (osd->osd_slots[slot - 1] != NULL) { osd_destructors[type][slot - 1](osd->osd_slots[slot - 1]); osd->osd_slots[slot - 1] = NULL; } for (i = osd->osd_nslots - 1; i >= 0; i--) { if (osd->osd_slots[i] != NULL) { OSD_DEBUG("Slot still has a value (type=%u, slot=%u).", type, i + 1); break; } } if (i == -1) { /* No values left for this object. */ OSD_DEBUG("No more slots left (type=%u).", type); if (!list_locked) mtx_lock(&osd_list_lock[type]); LIST_REMOVE(osd, osd_next); if (!list_locked) mtx_unlock(&osd_list_lock[type]); free(osd->osd_slots, M_OSD); osd->osd_slots = NULL; osd->osd_nslots = 0; } else if (slot == osd->osd_nslots) { /* This was the last slot. */ osd->osd_slots = realloc(osd->osd_slots, sizeof(void *) * (i + 1), M_OSD, M_NOWAIT | M_ZERO); /* * We always reallocate to smaller size, so we assume it will * always succeed. */ KASSERT(osd->osd_slots != NULL, ("realloc() failed")); osd->osd_nslots = i + 1; OSD_DEBUG("Reducing slots array to %u (type=%u).", osd->osd_nslots, type); } } int osd_call(u_int type, u_int method, void *obj, void *data) { osd_method_t methodfun; int error, i; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); KASSERT(method < osd_nmethods[type], ("Invalid method.")); /* * Call this method for every slot that defines it, stopping if an * error is encountered. */ error = 0; sx_slock(&osd_module_lock[type]); for (i = 0; i < osd_nslots[type]; i++) { methodfun = osd_methods[type][i * osd_nmethods[type] + method]; if (methodfun != NULL && (error = methodfun(obj, data)) != 0) break; } sx_sunlock(&osd_module_lock[type]); return (error); } void osd_exit(u_int type, struct osd *osd) { struct rm_priotracker tracker; u_int i; KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type.")); if (osd->osd_nslots == 0) { KASSERT(osd->osd_slots == NULL, ("Non-null osd_slots.")); /* No OSD attached, just leave. */ return; } rm_rlock(&osd_object_lock[type], &tracker); for (i = 1; i <= osd->osd_nslots; i++) { if (osd_destructors[type][i - 1] != NULL) do_osd_del(type, osd, i, 0); else OSD_DEBUG("Unused slot (type=%u, slot=%u).", type, i); } rm_runlock(&osd_object_lock[type], &tracker); OSD_DEBUG("Object exit (type=%u).", type); } static void osd_init(void *arg __unused) { u_int i; for (i = OSD_FIRST; i <= OSD_LAST; i++) { osd_nslots[i] = 0; LIST_INIT(&osd_list[i]); sx_init(&osd_module_lock[i], "osd_module"); rm_init(&osd_object_lock[i], "osd_object"); mtx_init(&osd_list_lock[i], "osd_list", NULL, MTX_DEF); osd_destructors[i] = NULL; osd_methods[i] = NULL; } } SYSINIT(osd, SI_SUB_LOCK, SI_ORDER_ANY, osd_init, NULL);