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FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //sys/kern/subr_rman.c |
/*-
* Copyright 1998 Massachusetts Institute of Technology
*
* Permission to use, copy, modify, and distribute this software and
* its documentation for any purpose and without fee is hereby
* granted, provided that both the above copyright notice and this
* permission notice appear in all copies, that both the above
* copyright notice and this permission notice appear in all
* supporting documentation, and that the name of M.I.T. not be used
* in advertising or publicity pertaining to distribution of the
* software without specific, written prior permission. M.I.T. makes
* no representations about the suitability of this software for any
* purpose. It is provided "as is" without express or implied
* warranty.
*
* THIS SOFTWARE IS PROVIDED BY M.I.T. ``AS IS''. M.I.T. DISCLAIMS
* ALL EXPRESS OR IMPLIED WARRANTIES WITH REGARD TO THIS SOFTWARE,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT
* SHALL M.I.T. 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.
*/
/*
* The kernel resource manager. This code is responsible for keeping track
* of hardware resources which are apportioned out to various drivers.
* It does not actually assign those resources, and it is not expected
* that end-device drivers will call into this code directly. Rather,
* the code which implements the buses that those devices are attached to,
* and the code which manages CPU resources, will call this code, and the
* end-device drivers will make upcalls to that code to actually perform
* the allocation.
*
* There are two sorts of resources managed by this code. The first is
* the more familiar array (RMAN_ARRAY) type; resources in this class
* consist of a sequence of individually-allocatable objects which have
* been numbered in some well-defined order. Most of the resources
* are of this type, as it is the most familiar. The second type is
* called a gauge (RMAN_GAUGE), and models fungible resources (i.e.,
* resources in which each instance is indistinguishable from every
* other instance). The principal anticipated application of gauges
* is in the context of power consumption, where a bus may have a specific
* power budget which all attached devices share. RMAN_GAUGE is not
* implemented yet.
*
* For array resources, we make one simplifying assumption: two clients
* sharing the same resource must use the same range of indices. That
* is to say, sharing of overlapping-but-not-identical regions is not
* permitted.
*/
#include "opt_ddb.h"
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/sys/kern/subr_rman.c 222750 2011-06-06 13:12:56Z jhb $");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/limits.h>
#include <sys/lock.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/bus.h> /* XXX debugging */
#include <machine/bus.h>
#include <sys/rman.h>
#include <sys/sysctl.h>
#ifdef DDB
#include <ddb/ddb.h>
#endif
/*
* We use a linked list rather than a bitmap because we need to be able to
* represent potentially huge objects (like all of a processor's physical
* address space). That is also why the indices are defined to have type
* `unsigned long' -- that being the largest integral type in ISO C (1990).
* The 1999 version of C allows `long long'; we may need to switch to that
* at some point in the future, particularly if we want to support 36-bit
* addresses on IA32 hardware.
*/
struct resource_i {
struct resource r_r;
TAILQ_ENTRY(resource_i) r_link;
LIST_ENTRY(resource_i) r_sharelink;
LIST_HEAD(, resource_i) *r_sharehead;
u_long r_start; /* index of the first entry in this resource */
u_long r_end; /* index of the last entry (inclusive) */
u_int r_flags;
void *r_virtual; /* virtual address of this resource */
struct device *r_dev; /* device which has allocated this resource */
struct rman *r_rm; /* resource manager from whence this came */
int r_rid; /* optional rid for this resource. */
};
static int rman_debug = 0;
TUNABLE_INT("debug.rman_debug", &rman_debug);
SYSCTL_INT(_debug, OID_AUTO, rman_debug, CTLFLAG_RW,
&rman_debug, 0, "rman debug");
#define DPRINTF(params) if (rman_debug) printf params
static MALLOC_DEFINE(M_RMAN, "rman", "Resource manager");
struct rman_head rman_head;
static struct mtx rman_mtx; /* mutex to protect rman_head */
static int int_rman_activate_resource(struct rman *rm, struct resource_i *r,
struct resource_i **whohas);
static int int_rman_deactivate_resource(struct resource_i *r);
static int int_rman_release_resource(struct rman *rm, struct resource_i *r);
static __inline struct resource_i *
int_alloc_resource(int malloc_flag)
{
struct resource_i *r;
r = malloc(sizeof *r, M_RMAN, malloc_flag | M_ZERO);
if (r != NULL) {
r->r_r.__r_i = r;
}
return (r);
}
int
rman_init(struct rman *rm)
{
static int once = 0;
if (once == 0) {
once = 1;
TAILQ_INIT(&rman_head);
mtx_init(&rman_mtx, "rman head", NULL, MTX_DEF);
}
if (rm->rm_start == 0 && rm->rm_end == 0)
rm->rm_end = ~0ul;
if (rm->rm_type == RMAN_UNINIT)
panic("rman_init");
if (rm->rm_type == RMAN_GAUGE)
panic("implement RMAN_GAUGE");
TAILQ_INIT(&rm->rm_list);
rm->rm_mtx = malloc(sizeof *rm->rm_mtx, M_RMAN, M_NOWAIT | M_ZERO);
if (rm->rm_mtx == NULL)
return ENOMEM;
mtx_init(rm->rm_mtx, "rman", NULL, MTX_DEF);
mtx_lock(&rman_mtx);
TAILQ_INSERT_TAIL(&rman_head, rm, rm_link);
mtx_unlock(&rman_mtx);
return 0;
}
int
rman_manage_region(struct rman *rm, u_long start, u_long end)
{
struct resource_i *r, *s, *t;
DPRINTF(("rman_manage_region: <%s> request: start %#lx, end %#lx\n",
rm->rm_descr, start, end));
if (start < rm->rm_start || end > rm->rm_end)
return EINVAL;
r = int_alloc_resource(M_NOWAIT);
if (r == NULL)
return ENOMEM;
r->r_start = start;
r->r_end = end;
r->r_rm = rm;
mtx_lock(rm->rm_mtx);
/* Skip entries before us. */
TAILQ_FOREACH(s, &rm->rm_list, r_link) {
if (s->r_end == ULONG_MAX)
break;
if (s->r_end + 1 >= r->r_start)
break;
}
/* If we ran off the end of the list, insert at the tail. */
if (s == NULL) {
TAILQ_INSERT_TAIL(&rm->rm_list, r, r_link);
} else {
/* Check for any overlap with the current region. */
if (r->r_start <= s->r_end && r->r_end >= s->r_start)
return EBUSY;
/* Check for any overlap with the next region. */
t = TAILQ_NEXT(s, r_link);
if (t && r->r_start <= t->r_end && r->r_end >= t->r_start)
return EBUSY;
/*
* See if this region can be merged with the next region. If
* not, clear the pointer.
*/
if (t && (r->r_end + 1 != t->r_start || t->r_flags != 0))
t = NULL;
/* See if we can merge with the current region. */
if (s->r_end + 1 == r->r_start && s->r_flags == 0) {
/* Can we merge all 3 regions? */
if (t != NULL) {
s->r_end = t->r_end;
TAILQ_REMOVE(&rm->rm_list, t, r_link);
free(r, M_RMAN);
free(t, M_RMAN);
} else {
s->r_end = r->r_end;
free(r, M_RMAN);
}
} else if (t != NULL) {
/* Can we merge with just the next region? */
t->r_start = r->r_start;
free(r, M_RMAN);
} else if (s->r_end < r->r_start) {
TAILQ_INSERT_AFTER(&rm->rm_list, s, r, r_link);
} else {
TAILQ_INSERT_BEFORE(s, r, r_link);
}
}
mtx_unlock(rm->rm_mtx);
return 0;
}
int
rman_init_from_resource(struct rman *rm, struct resource *r)
{
int rv;
if ((rv = rman_init(rm)) != 0)
return (rv);
return (rman_manage_region(rm, r->__r_i->r_start, r->__r_i->r_end));
}
int
rman_fini(struct rman *rm)
{
struct resource_i *r;
mtx_lock(rm->rm_mtx);
TAILQ_FOREACH(r, &rm->rm_list, r_link) {
if (r->r_flags & RF_ALLOCATED) {
mtx_unlock(rm->rm_mtx);
return EBUSY;
}
}
/*
* There really should only be one of these if we are in this
* state and the code is working properly, but it can't hurt.
*/
while (!TAILQ_EMPTY(&rm->rm_list)) {
r = TAILQ_FIRST(&rm->rm_list);
TAILQ_REMOVE(&rm->rm_list, r, r_link);
free(r, M_RMAN);
}
mtx_unlock(rm->rm_mtx);
mtx_lock(&rman_mtx);
TAILQ_REMOVE(&rman_head, rm, rm_link);
mtx_unlock(&rman_mtx);
mtx_destroy(rm->rm_mtx);
free(rm->rm_mtx, M_RMAN);
return 0;
}
int
rman_first_free_region(struct rman *rm, u_long *start, u_long *end)
{
struct resource_i *r;
mtx_lock(rm->rm_mtx);
TAILQ_FOREACH(r, &rm->rm_list, r_link) {
if (!(r->r_flags & RF_ALLOCATED)) {
*start = r->r_start;
*end = r->r_end;
mtx_unlock(rm->rm_mtx);
return (0);
}
}
mtx_unlock(rm->rm_mtx);
return (ENOENT);
}
int
rman_last_free_region(struct rman *rm, u_long *start, u_long *end)
{
struct resource_i *r;
mtx_lock(rm->rm_mtx);
TAILQ_FOREACH_REVERSE(r, &rm->rm_list, resource_head, r_link) {
if (!(r->r_flags & RF_ALLOCATED)) {
*start = r->r_start;
*end = r->r_end;
mtx_unlock(rm->rm_mtx);
return (0);
}
}
mtx_unlock(rm->rm_mtx);
return (ENOENT);
}
/* Shrink or extend one or both ends of an allocated resource. */
int
rman_adjust_resource(struct resource *rr, u_long start, u_long end)
{
struct resource_i *r, *s, *t, *new;
struct rman *rm;
/* Not supported for shared resources. */
r = rr->__r_i;
if (r->r_flags & (RF_TIMESHARE | RF_SHAREABLE))
return (EINVAL);
/*
* This does not support wholesale moving of a resource. At
* least part of the desired new range must overlap with the
* existing resource.
*/
if (end < r->r_start || r->r_end < start)
return (EINVAL);
/*
* Find the two resource regions immediately adjacent to the
* allocated resource.
*/
rm = r->r_rm;
mtx_lock(rm->rm_mtx);
#ifdef INVARIANTS
TAILQ_FOREACH(s, &rm->rm_list, r_link) {
if (s == r)
break;
}
if (s == NULL)
panic("resource not in list");
#endif
s = TAILQ_PREV(r, resource_head, r_link);
t = TAILQ_NEXT(r, r_link);
KASSERT(s == NULL || s->r_end + 1 == r->r_start,
("prev resource mismatch"));
KASSERT(t == NULL || r->r_end + 1 == t->r_start,
("next resource mismatch"));
/*
* See if the changes are permitted. Shrinking is always allowed,
* but growing requires sufficient room in the adjacent region.
*/
if (start < r->r_start && (s == NULL || (s->r_flags & RF_ALLOCATED) ||
s->r_start > start)) {
mtx_unlock(rm->rm_mtx);
return (EBUSY);
}
if (end > r->r_end && (t == NULL || (t->r_flags & RF_ALLOCATED) ||
t->r_end < end)) {
mtx_unlock(rm->rm_mtx);
return (EBUSY);
}
/*
* While holding the lock, grow either end of the resource as
* needed and shrink either end if the shrinking does not require
* allocating a new resource. We can safely drop the lock and then
* insert a new range to handle the shrinking case afterwards.
*/
if (start < r->r_start ||
(start > r->r_start && s != NULL && !(s->r_flags & RF_ALLOCATED))) {
KASSERT(s->r_flags == 0, ("prev is busy"));
r->r_start = start;
if (s->r_start == start) {
TAILQ_REMOVE(&rm->rm_list, s, r_link);
free(s, M_RMAN);
} else
s->r_end = start - 1;
}
if (end > r->r_end ||
(end < r->r_end && t != NULL && !(t->r_flags & RF_ALLOCATED))) {
KASSERT(t->r_flags == 0, ("next is busy"));
r->r_end = end;
if (t->r_end == end) {
TAILQ_REMOVE(&rm->rm_list, t, r_link);
free(t, M_RMAN);
} else
t->r_start = end + 1;
}
mtx_unlock(rm->rm_mtx);
/*
* Handle the shrinking cases that require allocating a new
* resource to hold the newly-free region. We have to recheck
* if we still need this new region after acquiring the lock.
*/
if (start > r->r_start) {
new = int_alloc_resource(M_WAITOK);
new->r_start = r->r_start;
new->r_end = start - 1;
new->r_rm = rm;
mtx_lock(rm->rm_mtx);
r->r_start = start;
s = TAILQ_PREV(r, resource_head, r_link);
if (s != NULL && !(s->r_flags & RF_ALLOCATED)) {
s->r_end = start - 1;
free(new, M_RMAN);
} else
TAILQ_INSERT_BEFORE(r, new, r_link);
mtx_unlock(rm->rm_mtx);
}
if (end < r->r_end) {
new = int_alloc_resource(M_WAITOK);
new->r_start = end + 1;
new->r_end = r->r_end;
new->r_rm = rm;
mtx_lock(rm->rm_mtx);
r->r_end = end;
t = TAILQ_NEXT(r, r_link);
if (t != NULL && !(t->r_flags & RF_ALLOCATED)) {
t->r_start = end + 1;
free(new, M_RMAN);
} else
TAILQ_INSERT_AFTER(&rm->rm_list, r, new, r_link);
mtx_unlock(rm->rm_mtx);
}
return (0);
}
struct resource *
rman_reserve_resource_bound(struct rman *rm, u_long start, u_long end,
u_long count, u_long bound, u_int flags,
struct device *dev)
{
u_int want_activate;
struct resource_i *r, *s, *rv;
u_long rstart, rend, amask, bmask;
rv = NULL;
DPRINTF(("rman_reserve_resource_bound: <%s> request: [%#lx, %#lx], "
"length %#lx, flags %u, device %s\n", rm->rm_descr, start, end,
count, flags,
dev == NULL ? "<null>" : device_get_nameunit(dev)));
want_activate = (flags & RF_ACTIVE);
flags &= ~RF_ACTIVE;
mtx_lock(rm->rm_mtx);
for (r = TAILQ_FIRST(&rm->rm_list);
r && r->r_end < start;
r = TAILQ_NEXT(r, r_link))
;
if (r == NULL) {
DPRINTF(("could not find a region\n"));
goto out;
}
amask = (1ul << RF_ALIGNMENT(flags)) - 1;
/* If bound is 0, bmask will also be 0 */
bmask = ~(bound - 1);
/*
* First try to find an acceptable totally-unshared region.
*/
for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
DPRINTF(("considering [%#lx, %#lx]\n", s->r_start, s->r_end));
if (s->r_start + count - 1 > end) {
DPRINTF(("s->r_start (%#lx) + count - 1> end (%#lx)\n",
s->r_start, end));
break;
}
if (s->r_flags & RF_ALLOCATED) {
DPRINTF(("region is allocated\n"));
continue;
}
rstart = ulmax(s->r_start, start);
/*
* Try to find a region by adjusting to boundary and alignment
* until both conditions are satisfied. This is not an optimal
* algorithm, but in most cases it isn't really bad, either.
*/
do {
rstart = (rstart + amask) & ~amask;
if (((rstart ^ (rstart + count - 1)) & bmask) != 0)
rstart += bound - (rstart & ~bmask);
} while ((rstart & amask) != 0 && rstart < end &&
rstart < s->r_end);
rend = ulmin(s->r_end, ulmax(rstart + count - 1, end));
if (rstart > rend) {
DPRINTF(("adjusted start exceeds end\n"));
continue;
}
DPRINTF(("truncated region: [%#lx, %#lx]; size %#lx (requested %#lx)\n",
rstart, rend, (rend - rstart + 1), count));
if ((rend - rstart + 1) >= count) {
DPRINTF(("candidate region: [%#lx, %#lx], size %#lx\n",
rstart, rend, (rend - rstart + 1)));
if ((s->r_end - s->r_start + 1) == count) {
DPRINTF(("candidate region is entire chunk\n"));
rv = s;
rv->r_flags |= RF_ALLOCATED | flags;
rv->r_dev = dev;
goto out;
}
/*
* If s->r_start < rstart and
* s->r_end > rstart + count - 1, then
* we need to split the region into three pieces
* (the middle one will get returned to the user).
* Otherwise, we are allocating at either the
* beginning or the end of s, so we only need to
* split it in two. The first case requires
* two new allocations; the second requires but one.
*/
rv = int_alloc_resource(M_NOWAIT);
if (rv == NULL)
goto out;
rv->r_start = rstart;
rv->r_end = rstart + count - 1;
rv->r_flags = flags | RF_ALLOCATED;
rv->r_dev = dev;
rv->r_rm = rm;
if (s->r_start < rv->r_start && s->r_end > rv->r_end) {
DPRINTF(("splitting region in three parts: "
"[%#lx, %#lx]; [%#lx, %#lx]; [%#lx, %#lx]\n",
s->r_start, rv->r_start - 1,
rv->r_start, rv->r_end,
rv->r_end + 1, s->r_end));
/*
* We are allocating in the middle.
*/
r = int_alloc_resource(M_NOWAIT);
if (r == NULL) {
free(rv, M_RMAN);
rv = NULL;
goto out;
}
r->r_start = rv->r_end + 1;
r->r_end = s->r_end;
r->r_flags = s->r_flags;
r->r_rm = rm;
s->r_end = rv->r_start - 1;
TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
r_link);
TAILQ_INSERT_AFTER(&rm->rm_list, rv, r,
r_link);
} else if (s->r_start == rv->r_start) {
DPRINTF(("allocating from the beginning\n"));
/*
* We are allocating at the beginning.
*/
s->r_start = rv->r_end + 1;
TAILQ_INSERT_BEFORE(s, rv, r_link);
} else {
DPRINTF(("allocating at the end\n"));
/*
* We are allocating at the end.
*/
s->r_end = rv->r_start - 1;
TAILQ_INSERT_AFTER(&rm->rm_list, s, rv,
r_link);
}
goto out;
}
}
/*
* Now find an acceptable shared region, if the client's requirements
* allow sharing. By our implementation restriction, a candidate
* region must match exactly by both size and sharing type in order
* to be considered compatible with the client's request. (The
* former restriction could probably be lifted without too much
* additional work, but this does not seem warranted.)
*/
DPRINTF(("no unshared regions found\n"));
if ((flags & (RF_SHAREABLE | RF_TIMESHARE)) == 0)
goto out;
for (s = r; s; s = TAILQ_NEXT(s, r_link)) {
if (s->r_start > end)
break;
if ((s->r_flags & flags) != flags)
continue;
rstart = ulmax(s->r_start, start);
rend = ulmin(s->r_end, ulmax(start + count - 1, end));
if (s->r_start >= start && s->r_end <= end
&& (s->r_end - s->r_start + 1) == count &&
(s->r_start & amask) == 0 &&
((s->r_start ^ s->r_end) & bmask) == 0) {
rv = int_alloc_resource(M_NOWAIT);
if (rv == NULL)
goto out;
rv->r_start = s->r_start;
rv->r_end = s->r_end;
rv->r_flags = s->r_flags &
(RF_ALLOCATED | RF_SHAREABLE | RF_TIMESHARE);
rv->r_dev = dev;
rv->r_rm = rm;
if (s->r_sharehead == NULL) {
s->r_sharehead = malloc(sizeof *s->r_sharehead,
M_RMAN, M_NOWAIT | M_ZERO);
if (s->r_sharehead == NULL) {
free(rv, M_RMAN);
rv = NULL;
goto out;
}
LIST_INIT(s->r_sharehead);
LIST_INSERT_HEAD(s->r_sharehead, s,
r_sharelink);
s->r_flags |= RF_FIRSTSHARE;
}
rv->r_sharehead = s->r_sharehead;
LIST_INSERT_HEAD(s->r_sharehead, rv, r_sharelink);
goto out;
}
}
/*
* We couldn't find anything.
*/
out:
/*
* If the user specified RF_ACTIVE in the initial flags,
* which is reflected in `want_activate', we attempt to atomically
* activate the resource. If this fails, we release the resource
* and indicate overall failure. (This behavior probably doesn't
* make sense for RF_TIMESHARE-type resources.)
*/
if (rv && want_activate) {
struct resource_i *whohas;
if (int_rman_activate_resource(rm, rv, &whohas)) {
int_rman_release_resource(rm, rv);
rv = NULL;
}
}
mtx_unlock(rm->rm_mtx);
return (rv == NULL ? NULL : &rv->r_r);
}
struct resource *
rman_reserve_resource(struct rman *rm, u_long start, u_long end, u_long count,
u_int flags, struct device *dev)
{
return (rman_reserve_resource_bound(rm, start, end, count, 0, flags,
dev));
}
static int
int_rman_activate_resource(struct rman *rm, struct resource_i *r,
struct resource_i **whohas)
{
struct resource_i *s;
int ok;
/*
* If we are not timesharing, then there is nothing much to do.
* If we already have the resource, then there is nothing at all to do.
* If we are not on a sharing list with anybody else, then there is
* little to do.
*/
if ((r->r_flags & RF_TIMESHARE) == 0
|| (r->r_flags & RF_ACTIVE) != 0
|| r->r_sharehead == NULL) {
r->r_flags |= RF_ACTIVE;
return 0;
}
ok = 1;
for (s = LIST_FIRST(r->r_sharehead); s && ok;
s = LIST_NEXT(s, r_sharelink)) {
if ((s->r_flags & RF_ACTIVE) != 0) {
ok = 0;
*whohas = s;
}
}
if (ok) {
r->r_flags |= RF_ACTIVE;
return 0;
}
return EBUSY;
}
int
rman_activate_resource(struct resource *re)
{
int rv;
struct resource_i *r, *whohas;
struct rman *rm;
r = re->__r_i;
rm = r->r_rm;
mtx_lock(rm->rm_mtx);
rv = int_rman_activate_resource(rm, r, &whohas);
mtx_unlock(rm->rm_mtx);
return rv;
}
int
rman_await_resource(struct resource *re, int pri, int timo)
{
int rv;
struct resource_i *r, *whohas;
struct rman *rm;
r = re->__r_i;
rm = r->r_rm;
mtx_lock(rm->rm_mtx);
for (;;) {
rv = int_rman_activate_resource(rm, r, &whohas);
if (rv != EBUSY)
return (rv); /* returns with mutex held */
if (r->r_sharehead == NULL)
panic("rman_await_resource");
whohas->r_flags |= RF_WANTED;
rv = msleep(r->r_sharehead, rm->rm_mtx, pri, "rmwait", timo);
if (rv) {
mtx_unlock(rm->rm_mtx);
return (rv);
}
}
}
static int
int_rman_deactivate_resource(struct resource_i *r)
{
r->r_flags &= ~RF_ACTIVE;
if (r->r_flags & RF_WANTED) {
r->r_flags &= ~RF_WANTED;
wakeup(r->r_sharehead);
}
return 0;
}
int
rman_deactivate_resource(struct resource *r)
{
struct rman *rm;
rm = r->__r_i->r_rm;
mtx_lock(rm->rm_mtx);
int_rman_deactivate_resource(r->__r_i);
mtx_unlock(rm->rm_mtx);
return 0;
}
static int
int_rman_release_resource(struct rman *rm, struct resource_i *r)
{
struct resource_i *s, *t;
if (r->r_flags & RF_ACTIVE)
int_rman_deactivate_resource(r);
/*
* Check for a sharing list first. If there is one, then we don't
* have to think as hard.
*/
if (r->r_sharehead) {
/*
* If a sharing list exists, then we know there are at
* least two sharers.
*
* If we are in the main circleq, appoint someone else.
*/
LIST_REMOVE(r, r_sharelink);
s = LIST_FIRST(r->r_sharehead);
if (r->r_flags & RF_FIRSTSHARE) {
s->r_flags |= RF_FIRSTSHARE;
TAILQ_INSERT_BEFORE(r, s, r_link);
TAILQ_REMOVE(&rm->rm_list, r, r_link);
}
/*
* Make sure that the sharing list goes away completely
* if the resource is no longer being shared at all.
*/
if (LIST_NEXT(s, r_sharelink) == NULL) {
free(s->r_sharehead, M_RMAN);
s->r_sharehead = NULL;
s->r_flags &= ~RF_FIRSTSHARE;
}
goto out;
}
/*
* Look at the adjacent resources in the list and see if our
* segment can be merged with any of them. If either of the
* resources is allocated or is not exactly adjacent then they
* cannot be merged with our segment.
*/
s = TAILQ_PREV(r, resource_head, r_link);
if (s != NULL && ((s->r_flags & RF_ALLOCATED) != 0 ||
s->r_end + 1 != r->r_start))
s = NULL;
t = TAILQ_NEXT(r, r_link);
if (t != NULL && ((t->r_flags & RF_ALLOCATED) != 0 ||
r->r_end + 1 != t->r_start))
t = NULL;
if (s != NULL && t != NULL) {
/*
* Merge all three segments.
*/
s->r_end = t->r_end;
TAILQ_REMOVE(&rm->rm_list, r, r_link);
TAILQ_REMOVE(&rm->rm_list, t, r_link);
free(t, M_RMAN);
} else if (s != NULL) {
/*
* Merge previous segment with ours.
*/
s->r_end = r->r_end;
TAILQ_REMOVE(&rm->rm_list, r, r_link);
} else if (t != NULL) {
/*
* Merge next segment with ours.
*/
t->r_start = r->r_start;
TAILQ_REMOVE(&rm->rm_list, r, r_link);
} else {
/*
* At this point, we know there is nothing we
* can potentially merge with, because on each
* side, there is either nothing there or what is
* there is still allocated. In that case, we don't
* want to remove r from the list; we simply want to
* change it to an unallocated region and return
* without freeing anything.
*/
r->r_flags &= ~RF_ALLOCATED;
r->r_dev = NULL;
return 0;
}
out:
free(r, M_RMAN);
return 0;
}
int
rman_release_resource(struct resource *re)
{
int rv;
struct resource_i *r;
struct rman *rm;
r = re->__r_i;
rm = r->r_rm;
mtx_lock(rm->rm_mtx);
rv = int_rman_release_resource(rm, r);
mtx_unlock(rm->rm_mtx);
return (rv);
}
uint32_t
rman_make_alignment_flags(uint32_t size)
{
int i;
/*
* Find the hightest bit set, and add one if more than one bit
* set. We're effectively computing the ceil(log2(size)) here.
*/
for (i = 31; i > 0; i--)
if ((1 << i) & size)
break;
if (~(1 << i) & size)
i++;
return(RF_ALIGNMENT_LOG2(i));
}
void
rman_set_start(struct resource *r, u_long start)
{
r->__r_i->r_start = start;
}
u_long
rman_get_start(struct resource *r)
{
return (r->__r_i->r_start);
}
void
rman_set_end(struct resource *r, u_long end)
{
r->__r_i->r_end = end;
}
u_long
rman_get_end(struct resource *r)
{
return (r->__r_i->r_end);
}
u_long
rman_get_size(struct resource *r)
{
return (r->__r_i->r_end - r->__r_i->r_start + 1);
}
u_int
rman_get_flags(struct resource *r)
{
return (r->__r_i->r_flags);
}
void
rman_set_virtual(struct resource *r, void *v)
{
r->__r_i->r_virtual = v;
}
void *
rman_get_virtual(struct resource *r)
{
return (r->__r_i->r_virtual);
}
void
rman_set_bustag(struct resource *r, bus_space_tag_t t)
{
r->r_bustag = t;
}
bus_space_tag_t
rman_get_bustag(struct resource *r)
{
return (r->r_bustag);
}
void
rman_set_bushandle(struct resource *r, bus_space_handle_t h)
{
r->r_bushandle = h;
}
bus_space_handle_t
rman_get_bushandle(struct resource *r)
{
return (r->r_bushandle);
}
void
rman_set_rid(struct resource *r, int rid)
{
r->__r_i->r_rid = rid;
}
int
rman_get_rid(struct resource *r)
{
return (r->__r_i->r_rid);
}
void
rman_set_device(struct resource *r, struct device *dev)
{
r->__r_i->r_dev = dev;
}
struct device *
rman_get_device(struct resource *r)
{
return (r->__r_i->r_dev);
}
int
rman_is_region_manager(struct resource *r, struct rman *rm)
{
return (r->__r_i->r_rm == rm);
}
/*
* Sysctl interface for scanning the resource lists.
*
* We take two input parameters; the index into the list of resource
* managers, and the resource offset into the list.
*/
static int
sysctl_rman(SYSCTL_HANDLER_ARGS)
{
int *name = (int *)arg1;
u_int namelen = arg2;
int rman_idx, res_idx;
struct rman *rm;
struct resource_i *res;
struct resource_i *sres;
struct u_rman urm;
struct u_resource ures;
int error;
if (namelen != 3)
return (EINVAL);
if (bus_data_generation_check(name[0]))
return (EINVAL);
rman_idx = name[1];
res_idx = name[2];
/*
* Find the indexed resource manager
*/
mtx_lock(&rman_mtx);
TAILQ_FOREACH(rm, &rman_head, rm_link) {
if (rman_idx-- == 0)
break;
}
mtx_unlock(&rman_mtx);
if (rm == NULL)
return (ENOENT);
/*
* If the resource index is -1, we want details on the
* resource manager.
*/
if (res_idx == -1) {
bzero(&urm, sizeof(urm));
urm.rm_handle = (uintptr_t)rm;
if (rm->rm_descr != NULL)
strlcpy(urm.rm_descr, rm->rm_descr, RM_TEXTLEN);
urm.rm_start = rm->rm_start;
urm.rm_size = rm->rm_end - rm->rm_start + 1;
urm.rm_type = rm->rm_type;
error = SYSCTL_OUT(req, &urm, sizeof(urm));
return (error);
}
/*
* Find the indexed resource and return it.
*/
mtx_lock(rm->rm_mtx);
TAILQ_FOREACH(res, &rm->rm_list, r_link) {
if (res->r_sharehead != NULL) {
LIST_FOREACH(sres, res->r_sharehead, r_sharelink)
if (res_idx-- == 0) {
res = sres;
goto found;
}
}
else if (res_idx-- == 0)
goto found;
}
mtx_unlock(rm->rm_mtx);
return (ENOENT);
found:
bzero(&ures, sizeof(ures));
ures.r_handle = (uintptr_t)res;
ures.r_parent = (uintptr_t)res->r_rm;
ures.r_device = (uintptr_t)res->r_dev;
if (res->r_dev != NULL) {
if (device_get_name(res->r_dev) != NULL) {
snprintf(ures.r_devname, RM_TEXTLEN,
"%s%d",
device_get_name(res->r_dev),
device_get_unit(res->r_dev));
} else {
strlcpy(ures.r_devname, "nomatch",
RM_TEXTLEN);
}
} else {
ures.r_devname[0] = '\0';
}
ures.r_start = res->r_start;
ures.r_size = res->r_end - res->r_start + 1;
ures.r_flags = res->r_flags;
mtx_unlock(rm->rm_mtx);
error = SYSCTL_OUT(req, &ures, sizeof(ures));
return (error);
}
SYSCTL_NODE(_hw_bus, OID_AUTO, rman, CTLFLAG_RD, sysctl_rman,
"kernel resource manager");
#ifdef DDB
static void
dump_rman_header(struct rman *rm)
{
if (db_pager_quit)
return;
db_printf("rman %p: %s (0x%lx-0x%lx full range)\n",
rm, rm->rm_descr, rm->rm_start, rm->rm_end);
}
static void
dump_rman(struct rman *rm)
{
struct resource_i *r;
const char *devname;
if (db_pager_quit)
return;
TAILQ_FOREACH(r, &rm->rm_list, r_link) {
if (r->r_dev != NULL) {
devname = device_get_nameunit(r->r_dev);
if (devname == NULL)
devname = "nomatch";
} else
devname = NULL;
db_printf(" 0x%lx-0x%lx ", r->r_start, r->r_end);
if (devname != NULL)
db_printf("(%s)\n", devname);
else
db_printf("----\n");
if (db_pager_quit)
return;
}
}
DB_SHOW_COMMAND(rman, db_show_rman)
{
if (have_addr) {
dump_rman_header((struct rman *)addr);
dump_rman((struct rman *)addr);
}
}
DB_SHOW_COMMAND(rmans, db_show_rmans)
{
struct rman *rm;
TAILQ_FOREACH(rm, &rman_head, rm_link) {
dump_rman_header(rm);
}
}
DB_SHOW_ALL_COMMAND(rman, db_show_all_rman)
{
struct rman *rm;
TAILQ_FOREACH(rm, &rman_head, rm_link) {
dump_rman_header(rm);
dump_rman(rm);
}
}
DB_SHOW_ALIAS(allrman, db_show_all_rman);
#endif