bootinfo.c revision 48083 
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 1.19 1999/06/04 03:18:28 ghelmer 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_cdrom",	RB_CDROM},
51    {"boot_userconfig",	RB_CONFIG},
52    {"boot_ddb",	RB_KDB},
53    {"boot_gdb",	RB_GDB},
54    {"boot_single",	RB_SINGLE},
55    {"boot_verbose",	RB_VERBOSE},
56    {NULL,	0}
57};
58
59int
60bi_getboothowto(char *kargs)
61{
62    char	*cp;
63    int		howto;
64    int		active;
65    int		i;
66
67    /* Parse kargs */
68    howto = 0;
69    if (kargs  != NULL) {
70	cp = kargs;
71	active = 0;
72	while (*cp != 0) {
73	    if (!active && (*cp == '-')) {
74		active = 1;
75	    } else if (active)
76		switch (*cp) {
77		case 'a':
78		    howto |= RB_ASKNAME;
79		    break;
80		case 'c':
81		    howto |= RB_CONFIG;
82		    break;
83		case 'C':
84		    howto |= RB_CDROM;
85		    break;
86		case 'd':
87		    howto |= RB_KDB;
88		    break;
89		case 'g':
90		    howto |= RB_GDB;
91		    break;
92		case 'h':
93		    howto |= RB_SERIAL;
94		    break;
95		case 'r':
96		    howto |= RB_DFLTROOT;
97		    break;
98		case 's':
99		    howto |= RB_SINGLE;
100		    break;
101		case 'v':
102		    howto |= RB_VERBOSE;
103		    break;
104		default:
105		    active = 0;
106		    break;
107		}
108	    cp++;
109	}
110    }
111    /* get equivalents from the environment */
112    for (i = 0; howto_names[i].ev != NULL; i++)
113	if (getenv(howto_names[i].ev) != NULL)
114	    howto |= howto_names[i].mask;
115    if (!strcmp(getenv("console"), "comconsole"))
116	howto |= RB_SERIAL;
117    return(howto);
118}
119
120/*
121 * Copy the environment into the load area starting at (addr).
122 * Each variable is formatted as <name>=<value>, with a single nul
123 * separating each variable, and a double nul terminating the environment.
124 */
125vm_offset_t
126bi_copyenv(vm_offset_t addr)
127{
128    struct env_var	*ep;
129
130    /* traverse the environment */
131    for (ep = environ; ep != NULL; ep = ep->ev_next) {
132	i386_copyin(ep->ev_name, addr, strlen(ep->ev_name));
133	addr += strlen(ep->ev_name);
134	i386_copyin("=", addr, 1);
135	addr++;
136	if (ep->ev_value != NULL) {
137	    i386_copyin(ep->ev_value, addr, strlen(ep->ev_value));
138	    addr += strlen(ep->ev_value);
139	}
140	i386_copyin("", addr, 1);
141	addr++;
142    }
143    i386_copyin("", addr, 1);
144    addr++;
145    return(addr);
146}
147
148/*
149 * Copy module-related data into the load area, where it can be
150 * used as a directory for loaded modules.
151 *
152 * Module data is presented in a self-describing format.  Each datum
153 * is preceeded by a 32-bit identifier and a 32-bit size field.
154 *
155 * Currently, the following data are saved:
156 *
157 * MOD_NAME	(variable)		module name (string)
158 * MOD_TYPE	(variable)		module type (string)
159 * MOD_ARGS	(variable)		module parameters (string)
160 * MOD_ADDR	sizeof(vm_offset_t)	module load address
161 * MOD_SIZE	sizeof(size_t)		module size
162 * MOD_METADATA	(variable)		type-specific metadata
163 */
164#define COPY32(v, a) {				\
165    u_int32_t	x = (v);			\
166    i386_copyin(&x, a, sizeof(x));		\
167    a += sizeof(x);				\
168}
169
170#define MOD_STR(t, a, s) {			\
171    COPY32(t, a);				\
172    COPY32(strlen(s) + 1, a);			\
173    i386_copyin(s, a, strlen(s) + 1);		\
174    a += roundup(strlen(s) + 1, sizeof(u_long));\
175}
176
177#define MOD_NAME(a, s)	MOD_STR(MODINFO_NAME, a, s)
178#define MOD_TYPE(a, s)	MOD_STR(MODINFO_TYPE, a, s)
179#define MOD_ARGS(a, s)	MOD_STR(MODINFO_ARGS, a, s)
180
181#define MOD_VAR(t, a, s) {			\
182    COPY32(t, a);				\
183    COPY32(sizeof(s), a);			\
184    i386_copyin(&s, a, sizeof(s));		\
185    a += roundup(sizeof(s), sizeof(u_long));	\
186}
187
188#define MOD_ADDR(a, s)	MOD_VAR(MODINFO_ADDR, a, s)
189#define MOD_SIZE(a, s)	MOD_VAR(MODINFO_SIZE, a, s)
190
191#define MOD_METADATA(a, mm) {			\
192    COPY32(MODINFO_METADATA | mm->md_type, a);	\
193    COPY32(mm->md_size, a);			\
194    i386_copyin(mm->md_data, a, mm->md_size);	\
195    a += roundup(mm->md_size, sizeof(u_long));\
196}
197
198#define MOD_END(a) {				\
199    COPY32(MODINFO_END, a);			\
200    COPY32(0, a);				\
201}
202
203vm_offset_t
204bi_copymodules(vm_offset_t addr)
205{
206    struct loaded_module	*mp;
207    struct module_metadata	*md;
208
209    /* start with the first module on the list, should be the kernel */
210    for (mp = mod_findmodule(NULL, NULL); mp != NULL; mp = mp->m_next) {
211
212	MOD_NAME(addr, mp->m_name);	/* this field must come first */
213	MOD_TYPE(addr, mp->m_type);
214	if (mp->m_args)
215	    MOD_ARGS(addr, mp->m_args);
216	MOD_ADDR(addr, mp->m_addr);
217	MOD_SIZE(addr, mp->m_size);
218	for (md = mp->m_metadata; md != NULL; md = md->md_next)
219	    if (!(md->md_type & MODINFOMD_NOCOPY))
220		MOD_METADATA(addr, md);
221    }
222    MOD_END(addr);
223    return(addr);
224}
225
226/*
227 * Load the information expected by an i386 kernel.
228 *
229 * - The 'boothowto' argument is constructed
230 * - The 'botdev' argument is constructed
231 * - The 'bootinfo' struct is constructed, and copied into the kernel space.
232 * - The kernel environment is copied into kernel space.
233 * - Module metadata are formatted and placed in kernel space.
234 */
235int
236bi_load(char *args, int *howtop, int *bootdevp, vm_offset_t *bip)
237{
238    struct loaded_module	*xp;
239    struct i386_devdesc		*rootdev;
240    vm_offset_t			addr, bootinfo_addr;
241    char			*rootdevname;
242    int				bootdevnr, i;
243    u_int			pad;
244    char			*kernelname;
245    const char			*kernelpath;
246
247    *howtop = bi_getboothowto(args);
248
249    /*
250     * Allow the environment variable 'rootdev' to override the supplied device
251     * This should perhaps go to MI code and/or have $rootdev tested/set by
252     * MI code before launching the kernel.
253     */
254    rootdevname = getenv("rootdev");
255    i386_getdev((void **)(&rootdev), rootdevname, NULL);
256    if (rootdev == NULL) {		/* bad $rootdev/$currdev */
257	printf("can't determine root device\n");
258	return(EINVAL);
259    }
260
261    switch(rootdev->d_type) {
262    case DEVT_DISK:
263	/* pass in the BIOS device number of the current disk */
264	bi.bi_bios_dev = bd_unit2bios(rootdev->d_kind.biosdisk.unit);
265	bootdevnr = bd_getdev(rootdev);
266	if (bootdevnr != -1)
267	    break;
268	printf("root device %s invalid\n", i386_fmtdev(rootdev));
269	return(EINVAL);
270
271    default:
272	printf("aout_exec: WARNING - don't know how to boot from device type %d\n", rootdev->d_type);
273    }
274    free(rootdev);
275    *bootdevp = bootdevnr;
276
277    /* legacy bootinfo structure */
278    bi.bi_version = BOOTINFO_VERSION;
279    bi.bi_kernelname = 0;		/* XXX char * -> kernel name */
280    bi.bi_nfs_diskless = 0;		/* struct nfs_diskless * */
281    bi.bi_n_bios_used = 0;		/* XXX would have to hook biosdisk driver for these */
282    for (i = 0; i < N_BIOS_GEOM; i++)
283        bi.bi_bios_geom[i] = bd_getbigeom(i);
284    bi.bi_size = sizeof(bi);
285    bi.bi_memsizes_valid = 1;
286    bi.bi_basemem = getbasemem();
287    bi.bi_extmem = getextmem();
288
289    /* find the last module in the chain */
290    addr = 0;
291    for (xp = mod_findmodule(NULL, NULL); xp != NULL; xp = xp->m_next) {
292	if (addr < (xp->m_addr + xp->m_size))
293	    addr = xp->m_addr + xp->m_size;
294    }
295    /* pad to a page boundary */
296    pad = (u_int)addr & PAGE_MASK;
297    if (pad != 0) {
298	pad = PAGE_SIZE - pad;
299	addr += pad;
300    }
301
302    /* copy our environment */
303    bi.bi_envp = addr;
304    addr = bi_copyenv(addr);
305
306    /* pad to a page boundary */
307    pad = (u_int)addr & PAGE_MASK;
308    if (pad != 0) {
309	pad = PAGE_SIZE - pad;
310	addr += pad;
311    }
312    /* copy module list and metadata */
313    bi.bi_modulep = addr;
314    addr = bi_copymodules(addr);
315
316    /* all done copying stuff in, save end of loaded object space */
317    bi.bi_kernend = addr;
318
319    *howtop |= RB_BOOTINFO;		/* it's there now */
320
321    /*
322     * Get the kernel name, strip off any device prefix.
323     */
324    kernelname = getenv("kernelname");
325    i386_getdev(NULL, kernelname, &kernelpath);
326    bi.bi_kernelname = VTOP(kernelpath);
327    *bip = VTOP(&bi);
328
329    return(0);
330}
331