bootinfo.c revision 40034 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 *	$Id: bootinfo.c,v 1.9 1998/10/07 02:39:05 msmith Exp $
27 */
28
29#include <stand.h>
30#include <sys/param.h>
31#include <sys/reboot.h>
32#include <machine/bootinfo.h>
33#include "bootstrap.h"
34#include "libi386.h"
35#include "btxv86.h"
36
37static struct bootinfo	bi;
38
39/*
40 * Return a 'boothowto' value corresponding to the kernel arguments in
41 * (kargs) and any relevant environment variables.
42 */
43static struct
44{
45    char	*ev;
46    int		mask;
47} howto_names[] = {
48    {"boot_askname",	RB_ASKNAME},
49    {"boot_userconfig",	RB_CONFIG},
50    {"boot_ddb",	RB_KDB},
51    {"boot_gdb",	RB_GDB},
52    {"boot_single",	RB_SINGLE},
53    {"boot_verbose",	RB_VERBOSE},
54    {NULL,	0}
55};
56
57int
58bi_getboothowto(char *kargs)
59{
60    char	*cp;
61    int		howto;
62    int		active;
63    int		i;
64
65    /* Parse kargs */
66    howto = 0;
67    if (kargs  != NULL) {
68	cp = kargs;
69	active = 0;
70	while (*cp != 0) {
71	    if (!active && (*cp == '-')) {
72		active = 1;
73	    } else if (active)
74		switch (*cp) {
75		case 'a':
76		    howto |= RB_ASKNAME;
77		    break;
78		case 'c':
79		    howto |= RB_CONFIG;
80		    break;
81		case 'd':
82		    howto |= RB_KDB;
83		    break;
84		case 'g':
85		    howto |= RB_GDB;
86		    break;
87		case 'h':
88		    howto |= RB_SERIAL;
89		    break;
90		case 'r':
91		    howto |= RB_DFLTROOT;
92		    break;
93		case 's':
94		    howto |= RB_SINGLE;
95		    break;
96		case 'v':
97		    howto |= RB_VERBOSE;
98		    break;
99		default:
100		    active = 0;
101		    break;
102		}
103	    cp++;
104	}
105    }
106    /* get equivalents from the environment */
107    for (i = 0; howto_names[i].ev != NULL; i++)
108	if (getenv(howto_names[i].ev) != NULL)
109	    howto |= howto_names[i].mask;
110    if (!strcmp(getenv("console"), "comconsole"))
111	howto |= RB_SERIAL;
112    return(howto);
113}
114
115/*
116 * Copy the environment into the load area starting at (addr).
117 * Each variable is formatted as <name>=<value>, with a single nul
118 * separating each variable, and a double nul terminating the environment.
119 */
120vm_offset_t
121bi_copyenv(vm_offset_t addr)
122{
123    struct env_var	*ep;
124
125    /* traverse the environment */
126    for (ep = environ; ep != NULL; ep = ep->ev_next) {
127	i386_copyin(ep->ev_name, addr, strlen(ep->ev_name));
128	addr += strlen(ep->ev_name);
129	i386_copyin("=", addr, 1);
130	addr++;
131	if (ep->ev_value != NULL) {
132	    i386_copyin(ep->ev_value, addr, strlen(ep->ev_value));
133	    addr += strlen(ep->ev_value);
134	}
135	i386_copyin("", addr, 1);
136	addr++;
137    }
138    i386_copyin("", addr, 1);
139    addr++;
140    return(addr);
141}
142
143/*
144 * Copy module-related data into the load area, where it can be
145 * used as a directory for loaded modules.
146 *
147 * Module data is presented in a self-describing format.  Each datum
148 * is preceeded by a 32-bit identifier and a 32-bit size field.
149 *
150 * Currently, the following data are saved:
151 *
152 * MOD_NAME	(variable)		module name (string)
153 * MOD_TYPE	(variable)		module type (string)
154 * MOD_ADDR	sizeof(vm_offset_t)	module load address
155 * MOD_SIZE	sizeof(size_t)		module size
156 * MOD_METADATA	(variable)		type-specific metadata
157 */
158#define MOD_STR(t, a, s) {				\
159    u_int32_t ident = (t << 16) + strlen(s) + 1;	\
160    i386_copyin(&ident, a, sizeof(ident));		\
161    a += sizeof(ident);					\
162    i386_copyin(s, a, strlen(s) + 1);			\
163    a += strlen(s) + 1;					\
164}
165
166#define MOD_NAME(a, s)	MOD_STR(MODINFO_NAME, a, s)
167#define MOD_TYPE(a, s)	MOD_STR(MODINFO_TYPE, a, s)
168
169#define MOD_VAR(t, a, s) {			\
170    u_int32_t ident = (t << 16) + sizeof(s);	\
171    i386_copyin(&ident, a, sizeof(ident));	\
172    a += sizeof(ident);				\
173    i386_copyin(&s, a, sizeof(s));		\
174    a += sizeof(s);				\
175}
176
177#define MOD_ADDR(a, s)	MOD_VAR(MODINFO_ADDR, a, s)
178#define MOD_SIZE(a, s)	MOD_VAR(MODINFO_SIZE, a, s)
179
180#define MOD_METADATA(a, mm) {							\
181    u_int32_t ident = ((MODINFO_METADATA | mm->md_type) << 16) + mm->md_size;	\
182    i386_copyin(&ident, a, sizeof(ident));					\
183    a += sizeof(ident);								\
184    i386_copyin(mm->md_data, a, mm->md_size);					\
185    a += mm->md_size;								\
186}
187
188#define MOD_END(a) {				\
189    u_int32_t ident = 0;			\
190    i386_copyin(&ident, a, sizeof(ident));	\
191    a += sizeof(ident);				\
192    i386_copyin(&ident, a, sizeof(ident));	\
193    a += sizeof(ident);				\
194}
195
196vm_offset_t
197bi_copymodules(vm_offset_t addr)
198{
199    struct loaded_module	*mp;
200    struct module_metadata	*md;
201
202    /* start with the first module on the list, should be the kernel */
203    for (mp = mod_findmodule(NULL, NULL); mp != NULL; mp = mp->m_next) {
204
205	MOD_NAME(addr, mp->m_name);	/* this field must come first */
206	MOD_TYPE(addr, mp->m_type);
207	MOD_ADDR(addr, mp->m_addr);
208	MOD_SIZE(addr, mp->m_size);
209	for (md = mp->m_metadata; md != NULL; md = md->md_next)
210	    if (!(md->md_type & MODINFOMD_NOCOPY))
211		MOD_METADATA(addr, md);
212    }
213    MOD_END(addr);
214    return(addr);
215}
216
217/*
218 * Load the information expected by an i386 kernel.
219 *
220 * - The 'boothowto' argument is constructed
221 * - The 'botdev' argument is constructed
222 * - The 'bootinfo' struct is constructed, and copied into the kernel space.
223 * - The kernel environment is copied into kernel space.
224 * - Module metadata are formatted and placed in kernel space.
225 */
226int
227bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
228{
229    struct loaded_module	*xp;
230    struct i386_devdesc		*rootdev;
231    vm_offset_t			addr, bootinfo_addr;
232    char			*rootdevname;
233    int				bootdevnr;
234    u_int			pad;
235    char			*kernelname;
236    const char			*kernelpath;
237
238    *howtop = bi_getboothowto(args);
239
240    /*
241     * Allow the environment variable 'rootdev' to override the supplied device
242     * This should perhaps go to MI code and/or have $rootdev tested/set by
243     * MI code before launching the kernel.
244     */
245    rootdevname = getenv("rootdev");
246    i386_getdev((void **)(&rootdev), rootdevname, NULL);
247    if (rootdev == NULL) {		/* bad $rootdev/$currdev */
248	printf("can't determine root device\n");
249	return(EINVAL);
250    }
251
252    /* Boot from whatever the current device is */
253    i386_getdev((void **)(&rootdev), NULL, NULL);
254    switch(rootdev->d_type) {
255    case DEVT_DISK:
256	/* pass in the BIOS device number of the current disk */
257	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
258	bootdevnr = bd_getdev(rootdev);
259	break;
260
261    default:
262	printf("aout_exec: WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
263    }
264    free(rootdev);
265    *bootdevp = bootdevnr;
266
267    /* legacy bootinfo structure */
268    bi.bi_version = BOOTINFO_VERSION;
269    bi.bi_kernelname = 0;		/* XXX char * -> kernel name */
270    bi.bi_nfs_diskless = 0;		/* struct nfs_diskless * */
271    bi.bi_n_bios_used = 0;		/* XXX would have to hook biosdisk driver for these */
272    /* bi.bi_bios_geom[] */
273    bi.bi_size = sizeof(bi);
274    bi.bi_memsizes_valid = 1;
275    bi.bi_basemem = getbasemem();
276    bi.bi_extmem = getextmem();
277
278    /* find the last module in the chain */
279    for (xp = mod_findmodule(NULL, NULL); xp->m_next != NULL; xp = xp->m_next)
280	;
281    addr = xp->m_addr + xp->m_size;
282    /* pad to a page boundary */
283    pad = (u_int)addr & PAGE_MASK;
284    if (pad != 0) {
285	pad = PAGE_SIZE - pad;
286	addr += pad;
287    }
288
289    /* copy our environment */
290    bi.bi_envp = addr;
291    addr = bi_copyenv(addr);
292
293    /* pad to a page boundary */
294    pad = (u_int)addr & PAGE_MASK;
295    if (pad != 0) {
296	pad = PAGE_SIZE - pad;
297	addr += pad;
298    }
299    /* copy module list and metadata */
300    bi.bi_modulep = addr;
301    addr = bi_copymodules(addr);
302
303    /* all done copying stuff in, save end of loaded object space */
304    bi.bi_kernend = addr;
305
306    *howtop |= RB_BOOTINFO;		/* it's there now */
307
308    /*
309     * Get the kernel name, strip off any device prefix.
310     */
311    kernelname = getenv("kernelname");
312    i386_getdev(NULL, kernelname, &kernelpath);
313    bi.bi_kernelname = VTOP(kernelpath);
314    *bip = VTOP(&bi);
315
316    return(0);
317}
318