Added rmon_XXX methods.

1 files changed, 973 insertions, 0 deletions

diff --git a/freebsd/kern/subr_rman.c b/freebsd/kern/subr_rman.c
new file mode 100644
index 00000000..8561c0a4
--- /dev/null
+++ b/freebsd/kern/subr_rman.c
@@ -0,0 +1,973 @@
+#include <freebsd/machine/rtems-bsd-config.h>
+
+/*-
+ * 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 <freebsd/local/opt_ddb.h>
+
+#include <freebsd/sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <freebsd/sys/param.h>
+#include <freebsd/sys/systm.h>
+#include <freebsd/sys/kernel.h>
+#include <freebsd/sys/limits.h>
+#include <freebsd/sys/lock.h>
+#include <freebsd/sys/malloc.h>
+#include <freebsd/sys/mutex.h>
+#include <freebsd/sys/bus.h>		/* XXX debugging */
+#include <freebsd/machine/bus.h>
+#include <freebsd/sys/rman.h>
+#include <freebsd/sys/sysctl.h>
+
+#ifdef DDB
+#include <freebsd/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_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));
+	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;
+}
+
+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;
+		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(struct rman *rm)
+{
+	struct resource_i *r;
+	const char *devname;
+
+	if (db_pager_quit)
+		return;
+	db_printf("rman: %s\n", rm->rm_descr);
+	db_printf("    0x%lx-0x%lx (full range)\n", rm->rm_start, rm->rm_end);
+	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((struct rman *)addr);
+}
+
+DB_SHOW_ALL_COMMAND(rman, db_show_all_rman)
+{
+	struct rman *rm;
+
+	TAILQ_FOREACH(rm, &rman_head, rm_link)
+		dump_rman(rm);
+}
+DB_SHOW_ALIAS(allrman, db_show_all_rman);
+#endif