proc->thread stage 4: rework the VFS and DEVICE subsystems to take thread
[dragonfly.git] / sys / kern / vfs_conf.c
CommitLineData
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1/*-
2 * Copyright (c) 1999 Michael Smith
3 * All rights reserved.
4 * Copyright (c) 1999 Poul-Henning Kamp
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: src/sys/kern/vfs_conf.c,v 1.49.2.5 2003/01/07 11:56:53 joerg Exp $
dadab5e9 29 * $DragonFly: src/sys/kern/vfs_conf.c,v 1.3 2003/06/25 03:55:57 dillon Exp $
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30 */
31
32/*
33 * Locate and mount the root filesystem.
34 *
35 * The root filesystem is detailed in the kernel environment variable
36 * vfs.root.mountfrom, which is expected to be in the general format
37 *
38 * <vfsname>:[<path>]
39 * vfsname := the name of a VFS known to the kernel and capable
40 * of being mounted as root
41 * path := disk device name or other data used by the filesystem
42 * to locate its physical store
43 *
44 */
45
46#include "opt_rootdevname.h"
47
48#include <sys/param.h>
49#include <sys/kernel.h>
50#include <sys/systm.h>
51#include <sys/proc.h>
52#include <sys/vnode.h>
53#include <sys/mount.h>
54#include <sys/malloc.h>
55#include <sys/reboot.h>
56#include <sys/diskslice.h>
57#include <sys/disklabel.h>
58#include <sys/conf.h>
59#include <sys/cons.h>
60#include <paths.h>
61
62#include "opt_ddb.h"
63#ifdef DDB
64#include <ddb/ddb.h>
65#endif
66
67MALLOC_DEFINE(M_MOUNT, "mount", "vfs mount structure");
68
69#define ROOTNAME "root_device"
70
71struct vnode *rootvnode;
72
73/*
74 * The root specifiers we will try if RB_CDROM is specified.
75 */
76static char *cdrom_rootdevnames[] = {
77 "cd9660:cd0a",
78 "cd9660:acd0a",
79 "cd9660:wcd0a",
80 NULL
81};
82
83static void vfs_mountroot(void *junk);
84static int vfs_mountroot_try(char *mountfrom);
85static int vfs_mountroot_ask(void);
86static void gets(char *cp);
87
88/* legacy find-root code */
89char *rootdevnames[2] = {NULL, NULL};
90static int setrootbyname(char *name);
91
92SYSINIT(mountroot, SI_SUB_MOUNT_ROOT, SI_ORDER_SECOND, vfs_mountroot, NULL);
93
94/*
95 * Find and mount the root filesystem
96 */
97static void
98vfs_mountroot(void *junk)
99{
100 int i;
101
102 /*
103 * The root filesystem information is compiled in, and we are
104 * booted with instructions to use it.
105 */
106#ifdef ROOTDEVNAME
107 if ((boothowto & RB_DFLTROOT) &&
108 !vfs_mountroot_try(ROOTDEVNAME))
109 return;
110#endif
111 /*
112 * We are booted with instructions to prompt for the root filesystem,
113 * or to use the compiled-in default when it doesn't exist.
114 */
115 if (boothowto & (RB_DFLTROOT | RB_ASKNAME)) {
116 if (!vfs_mountroot_ask())
117 return;
118 }
119
120 /*
121 * We've been given the generic "use CDROM as root" flag. This is
122 * necessary because one media may be used in many different
123 * devices, so we need to search for them.
124 */
125 if (boothowto & RB_CDROM) {
126 for (i = 0; cdrom_rootdevnames[i] != NULL; i++) {
127 if (!vfs_mountroot_try(cdrom_rootdevnames[i]))
128 return;
129 }
130 }
131
132 /*
133 * Try to use the value read by the loader from /etc/fstab, or
134 * supplied via some other means. This is the preferred
135 * mechanism.
136 */
137 if (!vfs_mountroot_try(getenv("vfs.root.mountfrom")))
138 return;
139
140 /*
141 * Try values that may have been computed by the machine-dependant
142 * legacy code.
143 */
144 if (!vfs_mountroot_try(rootdevnames[0]))
145 return;
146 if (!vfs_mountroot_try(rootdevnames[1]))
147 return;
148
149 /*
150 * If we have a compiled-in default, and haven't already tried it, try
151 * it now.
152 */
153#ifdef ROOTDEVNAME
154 if (!(boothowto & RB_DFLTROOT))
155 if (!vfs_mountroot_try(ROOTDEVNAME))
156 return;
157#endif
158
159 /*
160 * Everything so far has failed, prompt on the console if we haven't
161 * already tried that.
162 */
163 if (!(boothowto & (RB_DFLTROOT | RB_ASKNAME)) && !vfs_mountroot_ask())
164 return;
165 panic("Root mount failed, startup aborted.");
166}
167
168/*
169 * Mount (mountfrom) as the root filesystem.
170 */
171static int
172vfs_mountroot_try(char *mountfrom)
173{
dadab5e9 174 struct thread *td = curthread;
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175 struct mount *mp;
176 char *vfsname, *path;
177 int error;
178 char patt[32];
179 int s;
180
181 vfsname = NULL;
182 path = NULL;
183 mp = NULL;
184 error = EINVAL;
185
186 if (mountfrom == NULL)
187 return(error); /* don't complain */
188
189 s = splcam(); /* Overkill, but annoying without it */
190 printf("Mounting root from %s\n", mountfrom);
191 splx(s);
192
193 /* parse vfs name and path */
194 vfsname = malloc(MFSNAMELEN, M_MOUNT, M_WAITOK);
195 path = malloc(MNAMELEN, M_MOUNT, M_WAITOK);
196 vfsname[0] = path[0] = 0;
197 sprintf(patt, "%%%d[a-z0-9]:%%%ds", MFSNAMELEN, MNAMELEN);
198 if (sscanf(mountfrom, patt, vfsname, path) < 1)
199 goto done;
200
201 /* allocate a root mount */
202 error = vfs_rootmountalloc(vfsname, path[0] != 0 ? path : ROOTNAME,
203 &mp);
204 if (error != 0) {
205 printf("Can't allocate root mount for filesystem '%s': %d\n",
206 vfsname, error);
207 goto done;
208 }
209 mp->mnt_flag |= MNT_ROOTFS;
210
211 /* do our best to set rootdev */
212 if ((path[0] != 0) && setrootbyname(path))
213 printf("setrootbyname failed\n");
214
215 /* If the root device is a type "memory disk", mount RW */
216 if (rootdev != NODEV && devsw(rootdev) &&
217 (devsw(rootdev)->d_flags & D_MEMDISK))
218 mp->mnt_flag &= ~MNT_RDONLY;
219
dadab5e9 220 error = VFS_MOUNT(mp, NULL, NULL, NULL, td);
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221
222done:
223 if (vfsname != NULL)
224 free(vfsname, M_MOUNT);
225 if (path != NULL)
226 free(path, M_MOUNT);
227 if (error != 0) {
228 if (mp != NULL) {
dadab5e9 229 vfs_unbusy(mp, td);
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230 free(mp, M_MOUNT);
231 }
232 printf("Root mount failed: %d\n", error);
233 } else {
234
235 /* register with list of mounted filesystems */
236 simple_lock(&mountlist_slock);
237 TAILQ_INSERT_HEAD(&mountlist, mp, mnt_list);
238 simple_unlock(&mountlist_slock);
239
240 /* sanity check system clock against root filesystem timestamp */
241 inittodr(mp->mnt_time);
dadab5e9 242 vfs_unbusy(mp, td);
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243 }
244 return(error);
245}
246
247/*
248 * Spin prompting on the console for a suitable root filesystem
249 */
250static int
251vfs_mountroot_ask(void)
252{
253 char name[128];
254 int i;
255 dev_t dev;
256
257 for(;;) {
258 printf("\nManual root filesystem specification:\n");
259 printf(" <fstype>:<device> Mount <device> using filesystem <fstype>\n");
260 printf(" eg. ufs:%sda0s1a\n", _PATH_DEV);
261 printf(" ? List valid disk boot devices\n");
262 printf(" <empty line> Abort manual input\n");
263 printf("\nmountroot> ");
264 gets(name);
265 if (name[0] == 0)
266 return(1);
267 if (name[0] == '?') {
268 printf("Possibly valid devices for 'ufs' root:\n");
269 for (i = 0; i < NUMCDEVSW; i++) {
270 dev = makedev(i, 0);
271 if (devsw(dev) != NULL)
272 printf(" \"%s\"", devsw(dev)->d_name);
273 }
274 printf("\n");
275 continue;
276 }
277 if (!vfs_mountroot_try(name))
278 return(0);
279 }
280}
281
282static void
283gets(char *cp)
284{
285 char *lp;
286 int c;
287
288 lp = cp;
289 for (;;) {
290 printf("%c", c = cngetc() & 0177);
291 switch (c) {
292 case -1:
293 case '\n':
294 case '\r':
295 *lp++ = '\0';
296 return;
297 case '\b':
298 case '\177':
299 if (lp > cp) {
300 printf(" \b");
301 lp--;
302 }
303 continue;
304 case '#':
305 lp--;
306 if (lp < cp)
307 lp = cp;
308 continue;
309 case '@':
310 case 'u' & 037:
311 lp = cp;
312 printf("%c", '\n');
313 continue;
314 default:
315 *lp++ = c;
316 }
317 }
318}
319
320/*
321 * Convert a given name to the dev_t of the disk-like device
322 * it refers to.
323 */
324dev_t
325getdiskbyname(char *name) {
326 char *cp;
327 int cd, unit, slice, part;
328 dev_t dev;
329
330 slice = 0;
331 part = 0;
332 if (strncmp(name, _PATH_DEV, sizeof(_PATH_DEV) - 1) == 0)
333 name += sizeof(_PATH_DEV) - 1;
334 cp = name;
335 while (*cp != '\0' && (*cp < '0' || *cp > '9') && *cp != '/')
336 cp++;
337 if (cp == name) {
338 printf("missing device name\n");
339 return (NODEV);
340 }
341 if (*cp == '\0' || *cp == '/')
342 unit = -1;
343 else
344 unit = *cp - '0';
345 *cp++ = '\0';
346 for (cd = 0; cd < NUMCDEVSW; cd++) {
347 dev = makedev(cd, 0);
348 if (devsw(dev) != NULL &&
349 strcmp(devsw(dev)->d_name, name) == 0)
350 goto gotit;
351 }
352 printf("no such device '%s'\n", name);
353 return (NODEV);
354gotit:
355 if (devsw(dev)->d_maj == major(rootdev))
356 /* driver has already configured rootdev, e. g. vinum */
357 return (rootdev);
358 if (unit == -1) {
359 printf("missing unit number\n");
360 return (NODEV);
361 }
362 while (*cp >= '0' && *cp <= '9')
363 unit = 10 * unit + *cp++ - '0';
364 if (*cp == 's' && cp[1] >= '0' && cp[1] <= '9') {
365 slice = cp[1] - '0' + 1;
366 cp += 2;
367 }
368 if (*cp >= 'a' && *cp <= 'h') {
369 part = *cp - 'a';
370 cp++;
371 }
372 if (*cp != '\0') {
373 printf("junk after name\n");
374 return (NODEV);
375 }
376 return (makedev(cd, dkmakeminor(unit, slice, part)));
377}
378
379/*
380 * Set rootdev to match (name), given that we expect it to
381 * refer to a disk-like device.
382 */
383static int
384setrootbyname(char *name)
385{
386 dev_t diskdev;
387
388 diskdev = getdiskbyname(name);
389 if (diskdev != NODEV) {
390 rootdev = diskdev;
391 return (0);
392 }
393
394 return (1);
395}
396
397#ifdef DDB
398DB_SHOW_COMMAND(disk, db_getdiskbyname)
399{
400 dev_t dev;
401
402 if (modif[0] == '\0') {
403 db_error("usage: show disk/devicename");
404 return;
405 }
406 dev = getdiskbyname(modif);
407 if (dev != NODEV)
408 db_printf("dev_t = %p\n", dev);
409 else
410 db_printf("No disk device matched.\n");
411}
412#endif