 @@ -1,258 +1,290 @@
-/*	$NetBSD: kern_uidinfo.c,v 1.11 2019/03/01 03:03:19 christos Exp $	*/
+/*	$NetBSD: kern_uidinfo.c,v 1.12 2021/04/01 06:25:45 simonb Exp $	*/
 /*-
  * Copyright (c) 1982, 1986, 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
  * (c) UNIX System Laboratories, Inc.
  * All or some portions of this file are derived from material licensed
  * to the University of California by American Telephone and Telegraph
  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
  * the permission of UNIX System Laboratories, Inc.
+ *
  * 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.
  * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
+ *
  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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>
-__KERNEL_RCSID(0, "$NetBSD: kern_uidinfo.c,v 1.11 2019/03/01 03:03:19 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_uidinfo.c,v 1.12 2021/04/01 06:25:45 simonb Exp $");
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kmem.h>
 #include <sys/proc.h>
 #include <sys/atomic.h>
 #include <sys/uidinfo.h>
 #include <sys/sysctl.h>
 #include <sys/kauth.h>
 #include <sys/cpu.h>
 static SLIST_HEAD(uihashhead, uidinfo) *uihashtbl;
 static u_long 		uihash;
 #define	UIHASH(uid)	(&uihashtbl[(uid) & uihash])
 static int
 sysctl_kern_uidinfo_cnt(SYSCTLFN_ARGS)
+{
 	static const struct {
 		const char *name;
 		u_int value;
 	} nv[] = {
 #define _MEM(n) { # n, offsetof(struct uidinfo, ui_ ## n) }
 		_MEM(proccnt),
 		_MEM(lwpcnt),
 		_MEM(lockcnt),
 		_MEM(semcnt),
 		_MEM(sbsize),
 #undef _MEM
 	};
 	for (size_t i = 0; i < __arraycount(nv); i++)
 		if (strcmp(nv[i].name, rnode->sysctl_name) == 0) {
 			uint64_t cnt;
 			struct sysctlnode node = *rnode;
 			struct uidinfo *uip;
 			node.sysctl_data = &cnt;
 			uip = uid_find(kauth_cred_geteuid(l->l_cred));
 			*(uint64_t *)node.sysctl_data =
 			    *(u_long *)((char *)uip + nv[i].value);
 			return sysctl_lookup(SYSCTLFN_CALL(&node));
+		}
 	return EINVAL;
+}
 static struct sysctllog *kern_uidinfo_sysctllog;
 static void
 sysctl_kern_uidinfo_setup(void)
+{
 	const struct sysctlnode *rnode, *cnode;
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, NULL, &rnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_NODE, "uidinfo",
 		       SYSCTL_DESCR("Resource usage per uid"),
 		       NULL, 0, NULL, 0,
 		       CTL_KERN, CTL_CREATE, CTL_EOL);
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, &rnode, &cnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_QUAD, "proccnt",
 		       SYSCTL_DESCR("Number of processes for the current user"),
 		       sysctl_kern_uidinfo_cnt, 0, NULL, 0,
 		       CTL_CREATE, CTL_EOL);
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, &rnode, &cnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_QUAD, "lwpcnt",
 		       SYSCTL_DESCR("Number of lwps for the current user"),
 		       sysctl_kern_uidinfo_cnt, 0, NULL, 0,
 		       CTL_CREATE, CTL_EOL);
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, &rnode, &cnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_QUAD, "lockcnt",
 		       SYSCTL_DESCR("Number of locks for the current user"),
 		       sysctl_kern_uidinfo_cnt, 0, NULL, 0,
 		       CTL_CREATE, CTL_EOL);
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, &rnode, &cnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_QUAD, "semcnt",
 		       SYSCTL_DESCR("Number of semaphores used for the current user"),
 		       sysctl_kern_uidinfo_cnt, 0, NULL, 0,
 		       CTL_CREATE, CTL_EOL);
 	sysctl_createv(&kern_uidinfo_sysctllog, 0, &rnode, &cnode,
 		       CTLFLAG_PERMANENT,
 		       CTLTYPE_QUAD, "sbsize",
 		       SYSCTL_DESCR("Socket buffers used for the current user"),
 		       sysctl_kern_uidinfo_cnt, 0, NULL, 0,
 		       CTL_CREATE, CTL_EOL);
+}
 static int
 uid_stats(struct hashstat_sysctl *hs, bool fill)
+{
 	struct uidinfo *uip;
 	uint64_t chain;
 	strlcpy(hs->hash_name, "uihash", sizeof(hs->hash_name));
 	strlcpy(hs->hash_desc, "user info (uid->used proc) hash",
 	    sizeof(hs->hash_desc));
 	if (!fill)
 		return 0;
 	hs->hash_size = uihash + 1;
 	for (size_t i = 0; i < hs->hash_size; i++) {
 		chain = 0;
 		SLIST_FOREACH(uip, &uihashtbl[i], ui_hash) {
 			membar_datadep_consumer();
 			chain++;
+		}
 		if (chain > 0) {
 			hs->hash_used++;
 			hs->hash_items += chain;
 			if (chain > hs->hash_maxchain)
 				hs->hash_maxchain = chain;
+		}
+	}
 	return 0;
+}
 void
 uid_init(void)
+{
 	/*
 	 * In case of MP system, SLIST_FOREACH would force a cache line
 	 * write-back for every modified 'uidinfo', thus we try to keep the
 	 * lists short.
 	 */
 	const u_int uihash_sz = (maxcpus > 1 ? 1024 : 64);
 	uihashtbl = hashinit(uihash_sz, HASH_SLIST, true, &uihash);
 	/*
 	 * Ensure that uid 0 is always in the user hash table, as
 	 * sbreserve() expects it available from interrupt context.
 	 */
 	(void)uid_find(0);
 	sysctl_kern_uidinfo_setup();
 	hashstat_register("uihash", uid_stats);
+}
 struct uidinfo *
 uid_find(uid_t uid)
+{
 	struct uidinfo *uip, *uip_first, *newuip;
 	struct uihashhead *uipp;
 	uipp = UIHASH(uid);
 	newuip = NULL;
 	/*
 	 * To make insertion atomic, abstraction of SLIST will be violated.
 	 */
 	uip_first = uipp->slh_first;
  again:
 	SLIST_FOREACH(uip, uipp, ui_hash) {
 		membar_datadep_consumer();
 		if (uip->ui_uid != uid)
 			continue;
 		if (newuip != NULL)
 			kmem_free(newuip, sizeof(*newuip));
 		return uip;
+	}
 	if (newuip == NULL)
 		newuip = kmem_zalloc(sizeof(*newuip), KM_SLEEP);
 	newuip->ui_uid = uid;
 	/*
 	 * If atomic insert is unsuccessful, another thread might be
 	 * allocated this 'uid', thus full re-check is needed.
 	 */
 	newuip->ui_hash.sle_next = uip_first;
 	membar_producer();
 	uip = atomic_cas_ptr(&uipp->slh_first, uip_first, newuip);
 	if (uip != uip_first) {
 		uip_first = uip;
 		goto again;
+	}
 	return newuip;
+}
 /*
  * Change the count associated with number of processes
  * a given user is using.
  */
 int
 chgproccnt(uid_t uid, int diff)
+{
 	struct uidinfo *uip;
 	long proccnt;
 	uip = uid_find(uid);
 	proccnt = atomic_add_long_nv(&uip->ui_proccnt, diff);
 	KASSERT(proccnt >= 0);
 	return proccnt;
+}
 /*
  * Change the count associated with number of lwps
  * a given user is using.
  */
 int
 chglwpcnt(uid_t uid, int diff)
+{
 	struct uidinfo *uip;
 	long lwpcnt;
 	uip = uid_find(uid);
 	lwpcnt = atomic_add_long_nv(&uip->ui_lwpcnt, diff);
 	KASSERT(lwpcnt >= 0);
 	return lwpcnt;
+}
 /*
  * Change the count associated with number of semaphores
  * a given user is using.
  */
 int
 chgsemcnt(uid_t uid, int diff)
+{
 	struct uidinfo *uip;
 	long semcnt;
 	uip = uid_find(uid);
 	semcnt = atomic_add_long_nv(&uip->ui_semcnt, diff);
 	KASSERT(semcnt >= 0);
 	return semcnt;
+}
 int
 chgsbsize(struct uidinfo *uip, u_long *hiwat, u_long to, rlim_t xmax)
+{
 	rlim_t nsb;
 	const long diff = to - *hiwat;
 	nsb = (rlim_t)atomic_add_long_nv((long *)&uip->ui_sbsize, diff);
 	if (diff > 0 && nsb > xmax) {
 		atomic_add_long((long *)&uip->ui_sbsize, -diff);
 		return 0;
+	}
 	*hiwat = to;
 	return 1;
+}