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.
34 #include <sys/fcntl.h>
35 #include <sys/malloc.h>
36 #include <sys/namei.h>
37 #include <sys/nlookup.h>
39 #include <dev/disk/dm/dm.h>
41 static TAILQ_HEAD(, dm_pdev) dm_pdev_list;
43 static struct lock dm_pdev_mutex;
45 static dm_pdev_t *dm_pdev_alloc(const char *);
46 static int dm_pdev_free(dm_pdev_t *);
47 static dm_pdev_t *dm_pdev_lookup_name(const char *);
50 * Find used pdev with name == dm_pdev_name.
51 * needs to be called with the dm_pdev_mutex held.
54 dm_pdev_lookup_name(const char *dm_pdev_name)
58 KKASSERT(dm_pdev_name != NULL);
60 TAILQ_FOREACH(dmp, &dm_pdev_list, next_pdev) {
61 if (strcmp(dm_pdev_name, dmp->name) == 0)
69 dm_dk_lookup(const char *dev_name, struct vnode **vpp)
71 struct nlookupdata nd;
74 error = nlookup_init(&nd, dev_name, UIO_SYSSPACE, NLC_FOLLOW);
78 error = vn_open(&nd, NULL, FREAD|FWRITE, 0);
92 * Since dm can have arbitrary stacking on any number of disks and any dm
93 * volume is at least stacked onto another disk, we need to adjust the
94 * dumping offset (which is a raw offset from the beginning of the lowest
95 * physical disk) taking into account the offset of the underlying device
96 * which in turn takes into account the offset below it, etc.
98 * This function adjusts the dumping offset that is passed to the next
99 * dev_ddump() so it is correct for that underlying device.
102 dm_pdev_correct_dump_offset(dm_pdev_t *pdev, off_t offset)
106 noffset = pdev->pdev_pinfo.reserved_blocks +
107 pdev->pdev_pinfo.media_offset / pdev->pdev_pinfo.media_blksize;
108 noffset *= DEV_BSIZE;
115 * Create entry for device with name dev_name and open vnode for it.
116 * If entry already exists in global TAILQ I will only increment
120 dm_pdev_insert(const char *dev_name)
126 KKASSERT(dev_name != NULL);
128 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
129 dmp = dm_pdev_lookup_name(dev_name);
133 dmdebug("pdev %s already in tree\n", dev_name);
134 lockmgr(&dm_pdev_mutex, LK_RELEASE);
138 if ((dmp = dm_pdev_alloc(dev_name)) == NULL) {
139 lockmgr(&dm_pdev_mutex, LK_RELEASE);
143 error = dm_dk_lookup(dev_name, &dmp->pdev_vnode);
145 dmdebug("Lookup on %s failed with error %d!\n",
148 lockmgr(&dm_pdev_mutex, LK_RELEASE);
153 if (dm_pdev_get_vattr(dmp, &va) == -1) {
154 dmdebug("getattr on %s failed\n", dev_name);
156 lockmgr(&dm_pdev_mutex, LK_RELEASE);
159 ksnprintf(dmp->udev_name, sizeof(dmp->udev_name),
160 "%d:%d", va.va_rmajor, va.va_rminor);
161 dmp->udev = dm_pdev_get_udev(dmp);
164 * Get us the partinfo from the underlying device, it's needed for
167 bzero(&dmp->pdev_pinfo, sizeof(dmp->pdev_pinfo));
168 error = dev_dioctl(dmp->pdev_vnode->v_rdev, DIOCGPART,
169 (void *)&dmp->pdev_pinfo, 0, proc0.p_ucred, NULL, NULL);
171 struct partinfo *dpart = &dmp->pdev_pinfo;
172 dmdebug("DIOCGPART offset=%ju size=%ju blocks=%ju blksize=%d\n",
176 dpart->media_blksize);
178 kprintf("dmp_pdev_insert DIOCGPART failed %d\n", error);
181 TAILQ_INSERT_TAIL(&dm_pdev_list, dmp, next_pdev);
182 lockmgr(&dm_pdev_mutex, LK_RELEASE);
184 dmdebug("pdev %s %s 0x%016jx\n",
185 dmp->name, dmp->udev_name, (uintmax_t)dmp->udev);
191 * Allocat new pdev structure if is not already present and
195 dm_pdev_alloc(const char *name)
199 dmp = kmalloc(sizeof(*dmp), M_DM, M_WAITOK | M_ZERO);
204 strlcpy(dmp->name, name, DM_MAX_DEV_NAME);
210 * Destroy allocated dm_pdev.
213 dm_pdev_free(dm_pdev_t *dmp)
217 KKASSERT(dmp != NULL);
219 if (dmp->pdev_vnode != NULL) {
220 err = vn_close(dmp->pdev_vnode, FREAD | FWRITE, NULL);
232 * This funcion is called from targets' destroy() handler.
233 * When I'm removing device from list, I have to decrement
234 * reference counter. If reference counter is 0 I will remove
235 * dmp from global list and from device list to. And I will CLOSE
239 * Decrement pdev reference counter if 0 remove it.
242 dm_pdev_decr(dm_pdev_t *dmp)
244 KKASSERT(dmp != NULL);
246 * If this was last reference remove dmp from
249 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
251 if (--dmp->ref_cnt == 0) {
252 TAILQ_REMOVE(&dm_pdev_list, dmp, next_pdev);
253 lockmgr(&dm_pdev_mutex, LK_RELEASE);
257 lockmgr(&dm_pdev_mutex, LK_RELEASE);
262 dm_pdev_get_udev(dm_pdev_t *dmp)
267 if (dmp->pdev_vnode == NULL)
270 ret = dm_pdev_get_vattr(dmp, &va);
274 ret = makeudev(va.va_rmajor, va.va_rminor);
280 dm_pdev_get_vattr(dm_pdev_t *dmp, struct vattr *vap)
284 if (dmp->pdev_vnode == NULL)
288 ret = VOP_GETATTR(dmp->pdev_vnode, vap);
296 * Initialize pdev subsystem.
301 TAILQ_INIT(&dm_pdev_list); /* initialize global pdev list */
302 lockinit(&dm_pdev_mutex, "dmpdev", 0, LK_CANRECURSE);
308 * Destroy all existing pdev's in device-mapper.
315 lockmgr(&dm_pdev_mutex, LK_EXCLUSIVE);
317 while ((dmp = TAILQ_FIRST(&dm_pdev_list)) != NULL) {
318 TAILQ_REMOVE(&dm_pdev_list, dmp, next_pdev);
321 KKASSERT(TAILQ_EMPTY(&dm_pdev_list));
323 lockmgr(&dm_pdev_mutex, LK_RELEASE);
325 lockuninit(&dm_pdev_mutex);