freebsd-skq/sys/kern/kern_osd.c
pfg cc22a86800 sys/kern: adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:20:12 +00:00

446 lines
12 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* 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) */
/*
* Lock key:
* (m) osd_module_lock
* (o) osd_object_lock
* (l) osd_list_lock
*/
struct osd_master {
struct sx osd_module_lock;
struct rmlock osd_object_lock;
struct mtx osd_list_lock;
LIST_HEAD(, osd) osd_list; /* (l) */
osd_destructor_t *osd_destructors; /* (o) */
osd_method_t *osd_methods; /* (m) */
u_int osd_ntslots; /* (m) */
const u_int osd_nmethods;
};
static MALLOC_DEFINE(M_OSD, "osd", "Object Specific Data");
static int osd_debug = 0;
SYSCTL_INT(_debug, OID_AUTO, osd, CTLFLAG_RWTUN, &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);
/*
* List of objects with OSD.
*/
struct osd_master osdm[OSD_LAST + 1] = {
[OSD_JAIL] = { .osd_nmethods = PR_MAXMETHOD },
};
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(&osdm[type].osd_module_lock);
/*
* First, we try to find unused slot.
*/
for (i = 0; i < osdm[type].osd_ntslots; i++) {
if (osdm[type].osd_destructors[i] == NULL) {
OSD_DEBUG("Unused slot found (type=%u, slot=%u).",
type, i);
break;
}
}
/*
* If no unused slot was found, allocate one.
*/
if (i == osdm[type].osd_ntslots) {
osdm[type].osd_ntslots++;
if (osdm[type].osd_nmethods != 0)
osdm[type].osd_methods = realloc(osdm[type].osd_methods,
sizeof(osd_method_t) * osdm[type].osd_ntslots *
osdm[type].osd_nmethods, M_OSD, M_WAITOK);
newptr = malloc(sizeof(osd_destructor_t) *
osdm[type].osd_ntslots, M_OSD, M_WAITOK);
rm_wlock(&osdm[type].osd_object_lock);
bcopy(osdm[type].osd_destructors, newptr,
sizeof(osd_destructor_t) * i);
free(osdm[type].osd_destructors, M_OSD);
osdm[type].osd_destructors = newptr;
rm_wunlock(&osdm[type].osd_object_lock);
OSD_DEBUG("New slot allocated (type=%u, slot=%u).",
type, i + 1);
}
osdm[type].osd_destructors[i] = destructor;
if (osdm[type].osd_nmethods != 0) {
for (m = 0; m < osdm[type].osd_nmethods; m++)
osdm[type].osd_methods[i * osdm[type].osd_nmethods + m]
= methods != NULL ? methods[m] : NULL;
}
sx_xunlock(&osdm[type].osd_module_lock);
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(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
sx_xlock(&osdm[type].osd_module_lock);
rm_wlock(&osdm[type].osd_object_lock);
/*
* Free all OSD for the given slot.
*/
mtx_lock(&osdm[type].osd_list_lock);
LIST_FOREACH_SAFE(osd, &osdm[type].osd_list, osd_next, tosd)
do_osd_del(type, osd, slot, 1);
mtx_unlock(&osdm[type].osd_list_lock);
/*
* Set destructor to NULL to free the slot.
*/
osdm[type].osd_destructors[slot - 1] = NULL;
if (slot == osdm[type].osd_ntslots) {
osdm[type].osd_ntslots--;
osdm[type].osd_destructors = realloc(osdm[type].osd_destructors,
sizeof(osd_destructor_t) * osdm[type].osd_ntslots, M_OSD,
M_NOWAIT | M_ZERO);
if (osdm[type].osd_nmethods != 0)
osdm[type].osd_methods = realloc(osdm[type].osd_methods,
sizeof(osd_method_t) * osdm[type].osd_ntslots *
osdm[type].osd_nmethods, M_OSD, M_NOWAIT | M_ZERO);
/*
* We always reallocate to smaller size, so we assume it will
* always succeed.
*/
KASSERT(osdm[type].osd_destructors != NULL &&
(osdm[type].osd_nmethods == 0 ||
osdm[type].osd_methods != 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(&osdm[type].osd_object_lock);
sx_xunlock(&osdm[type].osd_module_lock);
}
int
osd_set(u_int type, struct osd *osd, u_int slot, void *value)
{
return (osd_set_reserved(type, osd, slot, NULL, value));
}
void **
osd_reserve(u_int slot)
{
KASSERT(slot > 0, ("Invalid slot."));
OSD_DEBUG("Reserving slot array (slot=%u).", slot);
return (malloc(sizeof(void *) * slot, M_OSD, M_WAITOK | M_ZERO));
}
int
osd_set_reserved(u_int type, struct osd *osd, u_int slot, void **rsv,
void *value)
{
struct rm_priotracker tracker;
KASSERT(type >= OSD_FIRST && type <= OSD_LAST, ("Invalid type."));
KASSERT(slot > 0, ("Invalid slot."));
KASSERT(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
rm_rlock(&osdm[type].osd_object_lock, &tracker);
if (slot > osd->osd_nslots) {
void **newptr;
if (value == NULL) {
OSD_DEBUG(
"Not allocating null slot (type=%u, slot=%u).",
type, slot);
rm_runlock(&osdm[type].osd_object_lock, &tracker);
if (rsv)
osd_free_reserved(rsv);
return (0);
}
/*
* Too few slots allocated here, so we need to extend or create
* the array.
*/
if (rsv) {
/*
* Use the reserve passed in (assumed to be
* the right size).
*/
newptr = rsv;
if (osd->osd_nslots != 0) {
memcpy(newptr, osd->osd_slots,
sizeof(void *) * osd->osd_nslots);
free(osd->osd_slots, M_OSD);
}
} else {
newptr = realloc(osd->osd_slots, sizeof(void *) * slot,
M_OSD, M_NOWAIT | M_ZERO);
if (newptr == NULL) {
rm_runlock(&osdm[type].osd_object_lock,
&tracker);
return (ENOMEM);
}
}
if (osd->osd_nslots == 0) {
/*
* First OSD for this object, so we need to put it
* onto the list.
*/
mtx_lock(&osdm[type].osd_list_lock);
LIST_INSERT_HEAD(&osdm[type].osd_list, osd, osd_next);
mtx_unlock(&osdm[type].osd_list_lock);
OSD_DEBUG("Setting first slot (type=%u).", type);
} else
OSD_DEBUG("Growing slots array (type=%u).", type);
osd->osd_slots = newptr;
osd->osd_nslots = slot;
} else if (rsv)
osd_free_reserved(rsv);
OSD_DEBUG("Setting slot value (type=%u, slot=%u, value=%p).", type,
slot, value);
osd->osd_slots[slot - 1] = value;
rm_runlock(&osdm[type].osd_object_lock, &tracker);
return (0);
}
void
osd_free_reserved(void **rsv)
{
OSD_DEBUG("Discarding reserved slot array.");
free(rsv, M_OSD);
}
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(osdm[type].osd_destructors[slot - 1] != NULL, ("Unused slot."));
rm_rlock(&osdm[type].osd_object_lock, &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(&osdm[type].osd_object_lock, &tracker);
return (value);
}
void
osd_del(u_int type, struct osd *osd, u_int slot)
{
struct rm_priotracker tracker;
rm_rlock(&osdm[type].osd_object_lock, &tracker);
do_osd_del(type, osd, slot, 0);
rm_runlock(&osdm[type].osd_object_lock, &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(osdm[type].osd_destructors[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) {
osdm[type].osd_destructors[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(&osdm[type].osd_list_lock);
LIST_REMOVE(osd, osd_next);
if (!list_locked)
mtx_unlock(&osdm[type].osd_list_lock);
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 < osdm[type].osd_nmethods, ("Invalid method."));
/*
* Call this method for every slot that defines it, stopping if an
* error is encountered.
*/
error = 0;
sx_slock(&osdm[type].osd_module_lock);
for (i = 0; i < osdm[type].osd_ntslots; i++) {
methodfun = osdm[type].osd_methods[i * osdm[type].osd_nmethods +
method];
if (methodfun != NULL && (error = methodfun(obj, data)) != 0)
break;
}
sx_sunlock(&osdm[type].osd_module_lock);
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(&osdm[type].osd_object_lock, &tracker);
for (i = 1; i <= osd->osd_nslots; i++) {
if (osdm[type].osd_destructors[i - 1] != NULL)
do_osd_del(type, osd, i, 0);
else
OSD_DEBUG("Unused slot (type=%u, slot=%u).", type, i);
}
rm_runlock(&osdm[type].osd_object_lock, &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++) {
sx_init(&osdm[i].osd_module_lock, "osd_module");
rm_init(&osdm[i].osd_object_lock, "osd_object");
mtx_init(&osdm[i].osd_list_lock, "osd_list", NULL, MTX_DEF);
LIST_INIT(&osdm[i].osd_list);
osdm[i].osd_destructors = NULL;
osdm[i].osd_ntslots = 0;
osdm[i].osd_methods = NULL;
}
}
SYSINIT(osd, SI_SUB_LOCK, SI_ORDER_ANY, osd_init, NULL);