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>
35 #include <sys/fcntl.h>
36 #include <sys/malloc.h>
37 #include <sys/namei.h>
38 #include <sys/vnode.h>
39 #include <sys/nlookup.h>
41 #include <dev/disk/dm/dm.h>
43 static TAILQ_HEAD(, dm_pdev) dm_pdev_list;
45 static struct lock dm_pdev_mutex;
47 static dm_pdev_t *dm_pdev_alloc(const char *);
48 static int dm_pdev_free(dm_pdev_t *);
49 static dm_pdev_t *dm_pdev_lookup_name(const char *);
52 * Find used pdev with name == dm_pdev_name.
53 * needs to be called with the dm_pdev_mutex held.
56 dm_pdev_lookup_name(const char *dm_pdev_name)
60 KKASSERT(dm_pdev_name != NULL);
62 TAILQ_FOREACH(dmp, &dm_pdev_list, next_pdev) {
63 if (strcmp(dm_pdev_name, dmp->name) == 0)
71 dm_dk_lookup(const char *dev_name, struct vnode **vpp)
73 struct nlookupdata nd;
76 error = nlookup_init(&nd, dev_name, UIO_SYSSPACE, NLC_FOLLOW);
80 error = vn_open(&nd, NULL, FREAD|FWRITE, 0);
94 * Since dm can have arbitrary stacking on any number of disks and any dm
95 * volume is at least stacked onto another disk, we need to adjust the
96 * dumping offset (which is a raw offset from the beginning of the lowest
97 * physical disk) taking into account the offset of the underlying device
98 * which in turn takes into account the offset below it, etc.
100 * This function adjusts the dumping offset that is passed to the next
101 * dev_ddump() so it is correct for that underlying device.
104 dm_pdev_correct_dump_offset(dm_pdev_t *pdev, off_t offset)
108 noffset = pdev->pdev_pinfo.reserved_blocks +
109 pdev->pdev_pinfo.media_offset / pdev->pdev_pinfo.media_blksize;
110 noffset *= DEV_BSIZE;
117 * Create entry for device with name dev_name and open vnode for it.
118 * If entry already exists in global TAILQ I will only increment
122 dm_pdev_insert(const char *dev_name)
128 KKASSERT(dev_name != NULL);
130 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
131 dmp = dm_pdev_lookup_name(dev_name);
135 dmdebug("dmp_pdev_insert pdev %s already in tree\n", dev_name);
136 lockmgr(&dm_pdev_mutex, LK_RELEASE);
140 if ((dmp = dm_pdev_alloc(dev_name)) == NULL) {
141 lockmgr(&dm_pdev_mutex, LK_RELEASE);
145 error = dm_dk_lookup(dev_name, &dmp->pdev_vnode);
147 dmdebug("dk_lookup on device: %s failed with error %d!\n",
150 lockmgr(&dm_pdev_mutex, LK_RELEASE);
155 if (dm_pdev_get_vattr(dmp, &va) == -1) {
156 dmdebug("makeudev %s failed\n", dev_name);
158 lockmgr(&dm_pdev_mutex, LK_RELEASE);
161 ksnprintf(dmp->udev_name, sizeof(dmp->udev_name),
162 "%d:%d", va.va_rmajor, va.va_rminor);
163 dmp->udev = dm_pdev_get_udev(dmp);
166 * Get us the partinfo from the underlying device, it's needed for
169 bzero(&dmp->pdev_pinfo, sizeof(dmp->pdev_pinfo));
170 error = dev_dioctl(dmp->pdev_vnode->v_rdev, DIOCGPART,
171 (void *)&dmp->pdev_pinfo, 0, proc0.p_ucred, NULL, NULL);
173 struct partinfo *dpart = &dmp->pdev_pinfo;
174 dmdebug("dmp_pdev_insert DIOCGPART "
175 "offset=%ju size=%ju blocks=%ju blksize=%d\n",
179 dpart->media_blksize);
181 kprintf("dmp_pdev_insert DIOCGPART failed %d\n", error);
184 TAILQ_INSERT_TAIL(&dm_pdev_list, dmp, next_pdev);
185 lockmgr(&dm_pdev_mutex, LK_RELEASE);
187 dmdebug("dmp_pdev_insert pdev %s %s 0x%016jx\n",
188 dmp->name, dmp->udev_name, (uintmax_t)dmp->udev);
194 * Allocat new pdev structure if is not already present and
198 dm_pdev_alloc(const char *name)
202 dmp = kmalloc(sizeof(*dmp), M_DM, M_WAITOK | M_ZERO);
207 strlcpy(dmp->name, name, DM_MAX_DEV_NAME);
213 * Destroy allocated dm_pdev.
216 dm_pdev_free(dm_pdev_t *dmp)
220 KKASSERT(dmp != NULL);
222 if (dmp->pdev_vnode != NULL) {
223 err = vn_close(dmp->pdev_vnode, FREAD | FWRITE, NULL);
235 * This funcion is called from targets' destroy() handler.
236 * When I'm removing device from list, I have to decrement
237 * reference counter. If reference counter is 0 I will remove
238 * dmp from global list and from device list to. And I will CLOSE
242 * Decrement pdev reference counter if 0 remove it.
245 dm_pdev_decr(dm_pdev_t *dmp)
247 KKASSERT(dmp != NULL);
249 * If this was last reference remove dmp from
252 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
254 if (--dmp->ref_cnt == 0) {
255 TAILQ_REMOVE(&dm_pdev_list, dmp, next_pdev);
256 lockmgr(&dm_pdev_mutex, LK_RELEASE);
260 lockmgr(&dm_pdev_mutex, LK_RELEASE);
265 dm_pdev_get_udev(dm_pdev_t *dmp)
270 if (dmp->pdev_vnode == NULL)
273 ret = dm_pdev_get_vattr(dmp, &va);
277 ret = makeudev(va.va_rmajor, va.va_rminor);
283 dm_pdev_get_vattr(dm_pdev_t *dmp, struct vattr *vap)
287 if (dmp->pdev_vnode == NULL)
291 ret = VOP_GETATTR(dmp->pdev_vnode, vap);
299 * Initialize pdev subsystem.
304 TAILQ_INIT(&dm_pdev_list); /* initialize global pdev list */
305 lockinit(&dm_pdev_mutex, "dmpdev", 0, LK_CANRECURSE);
311 * Destroy all existing pdev's in device-mapper.
318 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
320 while ((dmp = TAILQ_FIRST(&dm_pdev_list)) != NULL) {
321 TAILQ_REMOVE(&dm_pdev_list, dmp, next_pdev);
324 KKASSERT(TAILQ_EMPTY(&dm_pdev_list));
326 lockmgr(&dm_pdev_mutex, LK_RELEASE);
328 lockuninit(&dm_pdev_mutex);