bootinfo.c revision 44572 
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 1.16 1999/01/24 00:12:04 msmith Exp $
27 */
28
29#include <stand.h>
30#include <sys/param.h>
31#include <sys/reboot.h>
32#include <sys/linker.h>
33#include <machine/bootinfo.h>
34#include "bootstrap.h"
35#include "libi386.h"
36#include "btxv86.h"
37
38static struct bootinfo	bi;
39
40/*
41 * Return a 'boothowto' value corresponding to the kernel arguments in
42 * (kargs) and any relevant environment variables.
43 */
44static struct
45{
46    char	*ev;
47    int		mask;
48} howto_names[] = {
49    {"boot_askname",	RB_ASKNAME},
50    {"boot_userconfig",	RB_CONFIG},
51    {"boot_ddb",	RB_KDB},
52    {"boot_gdb",	RB_GDB},
53    {"boot_single",	RB_SINGLE},
54    {"boot_verbose",	RB_VERBOSE},
55    {NULL,	0}
56};
57
58int
59bi_getboothowto(char *kargs)
60{
61    char	*cp;
62    int		howto;
63    int		active;
64    int		i;
65
66    /* Parse kargs */
67    howto = 0;
68    if (kargs  != NULL) {
69	cp = kargs;
70	active = 0;
71	while (*cp != 0) {
72	    if (!active && (*cp == '-')) {
73		active = 1;
74	    } else if (active)
75		switch (*cp) {
76		case 'a':
77		    howto |= RB_ASKNAME;
78		    break;
79		case 'c':
80		    howto |= RB_CONFIG;
81		    break;
82		case 'd':
83		    howto |= RB_KDB;
84		    break;
85		case 'g':
86		    howto |= RB_GDB;
87		    break;
88		case 'h':
89		    howto |= RB_SERIAL;
90		    break;
91		case 'r':
92		    howto |= RB_DFLTROOT;
93		    break;
94		case 's':
95		    howto |= RB_SINGLE;
96		    break;
97		case 'v':
98		    howto |= RB_VERBOSE;
99		    break;
100		default:
101		    active = 0;
102		    break;
103		}
104	    cp++;
105	}
106    }
107    /* get equivalents from the environment */
108    for (i = 0; howto_names[i].ev != NULL; i++)
109	if (getenv(howto_names[i].ev) != NULL)
110	    howto |= howto_names[i].mask;
111    if (!strcmp(getenv("console"), "comconsole"))
112	howto |= RB_SERIAL;
113    return(howto);
114}
115
116/*
117 * Copy the environment into the load area starting at (addr).
118 * Each variable is formatted as <name>=<value>, with a single nul
119 * separating each variable, and a double nul terminating the environment.
120 */
121vm_offset_t
122bi_copyenv(vm_offset_t addr)
123{
124    struct env_var	*ep;
125
126    /* traverse the environment */
127    for (ep = environ; ep != NULL; ep = ep->ev_next) {
128	i386_copyin(ep->ev_name, addr, strlen(ep->ev_name));
129	addr += strlen(ep->ev_name);
130	i386_copyin("=", addr, 1);
131	addr++;
132	if (ep->ev_value != NULL) {
133	    i386_copyin(ep->ev_value, addr, strlen(ep->ev_value));
134	    addr += strlen(ep->ev_value);
135	}
136	i386_copyin("", addr, 1);
137	addr++;
138    }
139    i386_copyin("", addr, 1);
140    addr++;
141    return(addr);
142}
143
144/*
145 * Copy module-related data into the load area, where it can be
146 * used as a directory for loaded modules.
147 *
148 * Module data is presented in a self-describing format.  Each datum
149 * is preceeded by a 32-bit identifier and a 32-bit size field.
150 *
151 * Currently, the following data are saved:
152 *
153 * MOD_NAME	(variable)		module name (string)
154 * MOD_TYPE	(variable)		module type (string)
155 * MOD_ARGS	(variable)		module parameters (string)
156 * MOD_ADDR	sizeof(vm_offset_t)	module load address
157 * MOD_SIZE	sizeof(size_t)		module size
158 * MOD_METADATA	(variable)		type-specific metadata
159 */
160#define COPY32(v, a) {				\
161    u_int32_t	x = (v);			\
162    i386_copyin(&x, a, sizeof(x));		\
163    a += sizeof(x);				\
164}
165
166#define MOD_STR(t, a, s) {			\
167    COPY32(t, a);				\
168    COPY32(strlen(s) + 1, a);			\
169    i386_copyin(s, a, strlen(s) + 1);		\
170    a += roundup(strlen(s) + 1, sizeof(u_long));\
171}
172
173#define MOD_NAME(a, s)	MOD_STR(MODINFO_NAME, a, s)
174#define MOD_TYPE(a, s)	MOD_STR(MODINFO_TYPE, a, s)
175#define MOD_ARGS(a, s)	MOD_STR(MODINFO_ARGS, a, s)
176
177#define MOD_VAR(t, a, s) {			\
178    COPY32(t, a);				\
179    COPY32(sizeof(s), a);			\
180    i386_copyin(&s, a, sizeof(s));		\
181    a += roundup(sizeof(s), sizeof(u_long));	\
182}
183
184#define MOD_ADDR(a, s)	MOD_VAR(MODINFO_ADDR, a, s)
185#define MOD_SIZE(a, s)	MOD_VAR(MODINFO_SIZE, a, s)
186
187#define MOD_METADATA(a, mm) {			\
188    COPY32(MODINFO_METADATA | mm->md_type, a);	\
189    COPY32(mm->md_size, a);			\
190    i386_copyin(mm->md_data, a, mm->md_size);	\
191    a += roundup(mm->md_size, sizeof(u_long));\
192}
193
194#define MOD_END(a) {				\
195    COPY32(MODINFO_END, a);			\
196    COPY32(0, a);				\
197}
198
199vm_offset_t
200bi_copymodules(vm_offset_t addr)
201{
202    struct loaded_module	*mp;
203    struct module_metadata	*md;
204
205    /* start with the first module on the list, should be the kernel */
206    for (mp = mod_findmodule(NULL, NULL); mp != NULL; mp = mp->m_next) {
207
208	MOD_NAME(addr, mp->m_name);	/* this field must come first */
209	MOD_TYPE(addr, mp->m_type);
210	MOD_ARGS(addr, mp->m_args);
211	MOD_ADDR(addr, mp->m_addr);
212	MOD_SIZE(addr, mp->m_size);
213	for (md = mp->m_metadata; md != NULL; md = md->md_next)
214	    if (!(md->md_type & MODINFOMD_NOCOPY))
215		MOD_METADATA(addr, md);
216    }
217    MOD_END(addr);
218    return(addr);
219}
220
221/*
222 * Load the information expected by an i386 kernel.
223 *
224 * - The 'boothowto' argument is constructed
225 * - The 'botdev' argument is constructed
226 * - The 'bootinfo' struct is constructed, and copied into the kernel space.
227 * - The kernel environment is copied into kernel space.
228 * - Module metadata are formatted and placed in kernel space.
229 */
230int
231bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
232{
233    struct loaded_module	*xp;
234    struct i386_devdesc		*rootdev;
235    vm_offset_t			addr, bootinfo_addr;
236    char			*rootdevname;
237    int				bootdevnr;
238    u_int			pad;
239    char			*kernelname;
240    const char			*kernelpath;
241
242    *howtop = bi_getboothowto(args);
243
244    /*
245     * Allow the environment variable 'rootdev' to override the supplied device
246     * This should perhaps go to MI code and/or have $rootdev tested/set by
247     * MI code before launching the kernel.
248     */
249    rootdevname = getenv("rootdev");
250    i386_getdev((void **)(&rootdev), rootdevname, NULL);
251    if (rootdev == NULL) {		/* bad $rootdev/$currdev */
252	printf("can't determine root device\n");
253	return(EINVAL);
254    }
255
256    switch(rootdev->d_type) {
257    case DEVT_DISK:
258	/* pass in the BIOS device number of the current disk */
259	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
260	bootdevnr = bd_getdev(rootdev);
261	if (bootdevnr != -1)
262	    break;
263	printf("root device %s invalid\n", i386_fmtdev(rootdev));
264	return(EINVAL);
265
266    default:
267	printf("aout_exec: WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
268    }
269    free(rootdev);
270    *bootdevp = bootdevnr;
271
272    /* legacy bootinfo structure */
273    bi.bi_version = BOOTINFO_VERSION;
274    bi.bi_kernelname = 0;		/* XXX char * -> kernel name */
275    bi.bi_nfs_diskless = 0;		/* struct nfs_diskless * */
276    bi.bi_n_bios_used = 0;		/* XXX would have to hook biosdisk driver for these */
277    /* bi.bi_bios_geom[] */
278    bi.bi_size = sizeof(bi);
279    bi.bi_memsizes_valid = 1;
280    bi.bi_basemem = getbasemem();
281    bi.bi_extmem = getextmem();
282
283    /* find the last module in the chain */
284    addr = 0;
285    for (xp = mod_findmodule(NULL, NULL); xp != NULL; xp = xp->m_next) {
286	if (addr < (xp->m_addr + xp->m_size))
287	    addr = xp->m_addr + xp->m_size;
288    }
289    /* pad to a page boundary */
290    pad = (u_int)addr & PAGE_MASK;
291    if (pad != 0) {
292	pad = PAGE_SIZE - pad;
293	addr += pad;
294    }
295
296    /* copy our environment */
297    bi.bi_envp = addr;
298    addr = bi_copyenv(addr);
299
300    /* pad to a page boundary */
301    pad = (u_int)addr & PAGE_MASK;
302    if (pad != 0) {
303	pad = PAGE_SIZE - pad;
304	addr += pad;
305    }
306    /* copy module list and metadata */
307    bi.bi_modulep = addr;
308    addr = bi_copymodules(addr);
309
310    /* all done copying stuff in, save end of loaded object space */
311    bi.bi_kernend = addr;
312
313    *howtop |= RB_BOOTINFO;		/* it's there now */
314
315    /*
316     * Get the kernel name, strip off any device prefix.
317     */
318    kernelname = getenv("kernelname");
319    i386_getdev(NULL, kernelname, &kernelpath);
320    bi.bi_kernelname = VTOP(kernelpath);
321    *bip = VTOP(&bi);
322
323    return(0);
324}
325