1 /* $NetBSD: dm_pdev.c,v 1.6 2010/01/04 00:19:08 haad Exp $ */
4 * Copyright (c) 2010-2011 Alex Hornung <alex@alexhornung.com>
5 * Copyright (c) 2008 The NetBSD Foundation, Inc.
8 * This code is derived from software contributed to The NetBSD Foundation
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
33 #include <sys/types.h>
34 #include <sys/param.h>
37 #include <sys/fcntl.h>
38 #include <sys/malloc.h>
39 #include <sys/namei.h>
40 #include <sys/vnode.h>
41 #include <sys/nlookup.h>
43 #include <dev/disk/dm/dm.h>
45 SLIST_HEAD(dm_pdevs, dm_pdev) dm_pdev_list;
47 struct lock dm_pdev_mutex;
49 static dm_pdev_t *dm_pdev_alloc(const char *);
50 static int dm_pdev_rem(dm_pdev_t *);
51 static dm_pdev_t *dm_pdev_lookup_name(const char *);
54 * Find used pdev with name == dm_pdev_name.
55 * needs to be called with the dm_pdev_mutex held.
58 dm_pdev_lookup_name(const char *dm_pdev_name)
62 KKASSERT(dm_pdev_name != NULL);
64 SLIST_FOREACH(dm_pdev, &dm_pdev_list, next_pdev) {
65 if (strcmp(dm_pdev_name, dm_pdev->name) == 0)
73 dm_dk_lookup(const char *dev_name, struct vnode **vpp)
75 struct nlookupdata nd;
78 error = nlookup_init(&nd, dev_name, UIO_SYSSPACE, NLC_FOLLOW);
82 error = vn_open(&nd, NULL, FREAD|FWRITE, 0);
96 * Since dm can have arbitrary stacking on any number of disks and any dm
97 * volume is at least stacked onto another disk, we need to adjust the
98 * dumping offset (which is a raw offset from the beginning of the lowest
99 * physical disk) taking into account the offset of the underlying device
100 * which in turn takes into account the offset below it, etc.
102 * This function adjusts the dumping offset that is passed to the next
103 * dev_ddump() so it is correct for that underlying device.
106 dm_pdev_correct_dump_offset(dm_pdev_t *pdev, off_t offset)
110 noffset = pdev->pdev_pinfo.reserved_blocks +
111 pdev->pdev_pinfo.media_offset / pdev->pdev_pinfo.media_blksize;
112 noffset *= DEV_BSIZE;
119 * Create entry for device with name dev_name and open vnode for it.
120 * If entry already exists in global SLIST I will only increment
124 dm_pdev_insert(const char *dev_name)
129 KKASSERT(dev_name != NULL);
131 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
132 dmp = dm_pdev_lookup_name(dev_name);
136 aprint_debug("dmp_pdev_insert pdev %s already in tree\n", dev_name);
137 lockmgr(&dm_pdev_mutex, LK_RELEASE);
140 lockmgr(&dm_pdev_mutex, LK_RELEASE);
142 if ((dmp = dm_pdev_alloc(dev_name)) == NULL)
145 error = dm_dk_lookup(dev_name, &dmp->pdev_vnode);
147 aprint_debug("dk_lookup on device: %s failed with error %d!\n",
155 * Get us the partinfo from the underlying device, it's needed for
158 bzero(&dmp->pdev_pinfo, sizeof(dmp->pdev_pinfo));
159 error = dev_dioctl(dmp->pdev_vnode->v_rdev, DIOCGPART,
160 (void *)&dmp->pdev_pinfo, 0, proc0.p_ucred, NULL);
162 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
163 SLIST_INSERT_HEAD(&dm_pdev_list, dmp, next_pdev);
164 lockmgr(&dm_pdev_mutex, LK_RELEASE);
170 * Allocat new pdev structure if is not already present and
174 dm_pdev_alloc(const char *name)
178 if ((dmp = kmalloc(sizeof(dm_pdev_t), M_DM, M_WAITOK | M_ZERO)) == NULL)
181 strlcpy(dmp->name, name, MAX_DEV_NAME);
184 dmp->pdev_vnode = NULL;
189 * Destroy allocated dm_pdev.
192 dm_pdev_rem(dm_pdev_t * dmp)
196 KKASSERT(dmp != NULL);
198 if (dmp->pdev_vnode != NULL) {
199 err = vn_close(dmp->pdev_vnode, FREAD | FWRITE);
210 * This funcion is called from dm_dev_remove_ioctl.
211 * When I'm removing device from list, I have to decrement
212 * reference counter. If reference counter is 0 I will remove
213 * dmp from global list and from device list to. And I will CLOSE
218 * Decrement pdev reference counter if 0 remove it.
221 dm_pdev_decr(dm_pdev_t * dmp)
223 KKASSERT(dmp != NULL);
225 * If this was last reference remove dmp from
228 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
230 if (--dmp->ref_cnt == 0) {
231 SLIST_REMOVE(&dm_pdev_list, dmp, dm_pdev, next_pdev);
232 lockmgr(&dm_pdev_mutex, LK_RELEASE);
236 lockmgr(&dm_pdev_mutex, LK_RELEASE);
241 * Initialize pdev subsystem.
246 SLIST_INIT(&dm_pdev_list); /* initialize global pdev list */
247 lockinit(&dm_pdev_mutex, "dmpdev", 0, LK_CANRECURSE);
253 * Destroy all existing pdev's in device-mapper.
260 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
261 while (!SLIST_EMPTY(&dm_pdev_list)) { /* List Deletion. */
263 dm_pdev = SLIST_FIRST(&dm_pdev_list);
265 SLIST_REMOVE_HEAD(&dm_pdev_list, next_pdev);
267 dm_pdev_rem(dm_pdev);
269 lockmgr(&dm_pdev_mutex, LK_RELEASE);
271 lockuninit(&dm_pdev_mutex);