1 /* $NetBSD: dm_pdev.c,v 1.6 2010/01/04 00:19:08 haad Exp $ */
4 * Copyright (c) 2008 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
32 #include <sys/types.h>
33 #include <sys/param.h>
36 #include <sys/fcntl.h>
37 #include <sys/malloc.h>
38 #include <sys/namei.h>
39 #include <sys/vnode.h>
40 #include <sys/nlookup.h>
44 SLIST_HEAD(dm_pdevs, dm_pdev) dm_pdev_list;
46 struct lock dm_pdev_mutex;
48 static dm_pdev_t *dm_pdev_alloc(const char *);
49 static int dm_pdev_rem(dm_pdev_t *);
50 static dm_pdev_t *dm_pdev_lookup_name(const char *);
53 * Find used pdev with name == dm_pdev_name.
56 dm_pdev_lookup_name(const char *dm_pdev_name)
62 KKASSERT(dm_pdev_name != NULL);
64 slen = strlen(dm_pdev_name);
66 SLIST_FOREACH(dm_pdev, &dm_pdev_list, next_pdev) {
67 dlen = strlen(dm_pdev->name);
72 if (strncmp(dm_pdev_name, dm_pdev->name, slen) == 0)
80 dm_dk_lookup(const char *dev_name, struct vnode **vpp)
82 struct nlookupdata nd;
86 if (this is a root mount) {
87 error = vn_opendisk(dev_name, FREAD|FWRITE, vpp);
92 error = nlookup_init(&nd, dev_name, UIO_SYSSPACE, NLC_FOLLOW);
96 error = vn_open(&nd, NULL, FREAD|FWRITE, 0);
105 * Create entry for device with name dev_name and open vnode for it.
106 * If entry already exists in global SLIST I will only increment
110 dm_pdev_insert(const char *dev_name)
115 KKASSERT(dev_name != NULL);
117 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
118 dmp = dm_pdev_lookup_name(dev_name);
122 aprint_debug("dmp_pdev_insert pdev %s already in tree\n", dev_name);
123 lockmgr(&dm_pdev_mutex, LK_RELEASE);
126 lockmgr(&dm_pdev_mutex, LK_RELEASE);
128 if ((dmp = dm_pdev_alloc(dev_name)) == NULL)
131 /* XXX: nlookup and/or vn_opendisk */
132 error = dm_dk_lookup(dev_name, &dmp->pdev_vnode);
134 aprint_debug("dk_lookup on device: %s failed with error %d!\n",
141 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
142 SLIST_INSERT_HEAD(&dm_pdev_list, dmp, next_pdev);
143 lockmgr(&dm_pdev_mutex, LK_RELEASE);
148 * Initialize pdev subsystem.
153 SLIST_INIT(&dm_pdev_list); /* initialize global pdev list */
154 lockinit(&dm_pdev_mutex, "dmpdev", 0, LK_CANRECURSE);
159 * Allocat new pdev structure if is not already present and
163 dm_pdev_alloc(const char *name)
167 if ((dmp = kmalloc(sizeof(dm_pdev_t), M_DM, M_WAITOK | M_ZERO)) == NULL)
170 strlcpy(dmp->name, name, MAX_DEV_NAME);
173 dmp->pdev_vnode = NULL;
178 * Destroy allocated dm_pdev.
181 dm_pdev_rem(dm_pdev_t * dmp)
185 KKASSERT(dmp != NULL);
187 if (dmp->pdev_vnode != NULL) {
188 err = vn_close(dmp->pdev_vnode, FREAD | FWRITE);
198 * Destroy all existing pdev's in device-mapper.
201 dm_pdev_destroy(void)
205 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
206 while (!SLIST_EMPTY(&dm_pdev_list)) { /* List Deletion. */
208 dm_pdev = SLIST_FIRST(&dm_pdev_list);
210 SLIST_REMOVE_HEAD(&dm_pdev_list, next_pdev);
212 dm_pdev_rem(dm_pdev);
214 lockmgr(&dm_pdev_mutex, LK_RELEASE);
216 lockuninit(&dm_pdev_mutex);
220 * This funcion is called from dm_dev_remove_ioctl.
221 * When I'm removing device from list, I have to decrement
222 * reference counter. If reference counter is 0 I will remove
223 * dmp from global list and from device list to. And I will CLOSE
228 * Decrement pdev reference counter if 0 remove it.
231 dm_pdev_decr(dm_pdev_t * dmp)
233 KKASSERT(dmp != NULL);
235 * If this was last reference remove dmp from
238 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
240 if (--dmp->ref_cnt == 0) {
241 SLIST_REMOVE(&dm_pdev_list, dmp, dm_pdev, next_pdev);
242 lockmgr(&dm_pdev_mutex, LK_RELEASE);
246 lockmgr(&dm_pdev_mutex, LK_RELEASE);
250 dm_pdev_dump_list(void)
254 aprint_verbose("Dumping dm_pdev_list \n");
256 SLIST_FOREACH(dmp, &dm_pdev_list, next_pdev) {
257 aprint_verbose("dm_pdev_name %s ref_cnt %d list_rf_cnt %d\n",
258 dmp->name, dmp->ref_cnt, dmp->list_ref_cnt);