metadata.c revision 265069 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * Copyright (C) 2006 Semihalf, Piotr Kruszynski <ppk@semihalf.com>
4 * Copyright (C) 2007-2008 Semihalf, Rafal Jaworowski <raj@semihalf.com>
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
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD: stable/10/sys/boot/uboot/common/metadata.c 265069 2014-04-29 00:36:51Z ian $");
31
32#include <stand.h>
33#include <sys/param.h>
34#include <sys/reboot.h>
35#include <sys/linker.h>
36
37#include <machine/elf.h>
38#include <machine/metadata.h>
39
40#include "api_public.h"
41#include "bootstrap.h"
42#include "glue.h"
43
44#if defined(LOADER_FDT_SUPPORT)
45#include "libuboot.h"
46#endif
47
48/*
49 * Return a 'boothowto' value corresponding to the kernel arguments in
50 * (kargs) and any relevant environment variables.
51 */
52static struct
53{
54	const char	*ev;
55	int		mask;
56} howto_names[] = {
57	{"boot_askname",	RB_ASKNAME},
58	{"boot_cdrom",		RB_CDROM},
59	{"boot_ddb",		RB_KDB},
60	{"boot_dfltroot",	RB_DFLTROOT},
61	{"boot_gdb",		RB_GDB},
62	{"boot_multicons",	RB_MULTIPLE},
63	{"boot_mute",		RB_MUTE},
64	{"boot_pause",		RB_PAUSE},
65	{"boot_serial",		RB_SERIAL},
66	{"boot_single",		RB_SINGLE},
67	{"boot_verbose",	RB_VERBOSE},
68	{NULL,			0}
69};
70
71static int
72md_getboothowto(char *kargs)
73{
74	char	*cp;
75	char	*p;
76	int	howto;
77	int	active;
78	int	i;
79
80	/* Parse kargs */
81	howto = 0;
82	if (kargs != NULL) {
83		cp = kargs;
84		active = 0;
85		while (*cp != 0) {
86			if (!active && (*cp == '-'))
87				active = 1;
88			else if (active)
89				switch (*cp) {
90				case 'a':
91					howto |= RB_ASKNAME;
92					break;
93				case 'C':
94					howto |= RB_CDROM;
95					break;
96				case 'd':
97					howto |= RB_KDB;
98					break;
99				case 'D':
100					howto |= RB_MULTIPLE;
101					break;
102				case 'm':
103					howto |= RB_MUTE;
104					break;
105				case 'g':
106					howto |= RB_GDB;
107					break;
108				case 'h':
109					howto |= RB_SERIAL;
110					break;
111				case 'p':
112					howto |= RB_PAUSE;
113					break;
114				case 'r':
115					howto |= RB_DFLTROOT;
116					break;
117				case 's':
118					howto |= RB_SINGLE;
119					break;
120				case 'v':
121					howto |= RB_VERBOSE;
122					break;
123				default:
124					active = 0;
125					break;
126				}
127				cp++;
128		}
129	}
130
131	/* get equivalents from the environment */
132	for (i = 0; howto_names[i].ev != NULL; i++) {
133		if (getenv(howto_names[i].ev) != NULL)
134			howto |= howto_names[i].mask;
135	}
136	if ((p = getenv("console"))) {
137		if (!strcmp(p, "comconsole"))
138			howto |= RB_SERIAL;
139		if (!strcmp(p, "nullconsole"))
140			howto |= RB_MUTE;
141	}
142
143	return(howto);
144}
145
146/*
147 * Copy the environment into the load area starting at (addr).
148 * Each variable is formatted as <name>=<value>, with a single nul
149 * separating each variable, and a double nul terminating the environment.
150 */
151static vm_offset_t
152md_copyenv(vm_offset_t addr)
153{
154	struct env_var	*ep;
155
156	/* traverse the environment */
157	for (ep = environ; ep != NULL; ep = ep->ev_next) {
158		archsw.arch_copyin(ep->ev_name, addr, strlen(ep->ev_name));
159		addr += strlen(ep->ev_name);
160		archsw.arch_copyin("=", addr, 1);
161		addr++;
162		if (ep->ev_value != NULL) {
163			archsw.arch_copyin(ep->ev_value, addr,
164			    strlen(ep->ev_value));
165			addr += strlen(ep->ev_value);
166		}
167		archsw.arch_copyin("", addr, 1);
168		addr++;
169	}
170	archsw.arch_copyin("", addr, 1);
171	addr++;
172	return(addr);
173}
174
175/*
176 * Copy module-related data into the load area, where it can be
177 * used as a directory for loaded modules.
178 *
179 * Module data is presented in a self-describing format.  Each datum
180 * is preceded by a 32-bit identifier and a 32-bit size field.
181 *
182 * Currently, the following data are saved:
183 *
184 * MOD_NAME	(variable)		module name (string)
185 * MOD_TYPE	(variable)		module type (string)
186 * MOD_ARGS	(variable)		module parameters (string)
187 * MOD_ADDR	sizeof(vm_offset_t)	module load address
188 * MOD_SIZE	sizeof(size_t)		module size
189 * MOD_METADATA	(variable)		type-specific metadata
190 */
191#define	COPY32(v, a, c) {			\
192    u_int32_t	x = (v);			\
193    if (c)					\
194	archsw.arch_copyin(&x, a, sizeof(x));	\
195    a += sizeof(x);				\
196}
197
198#define	MOD_STR(t, a, s, c) {			\
199    COPY32(t, a, c);				\
200    COPY32(strlen(s) + 1, a, c)			\
201    if (c)					\
202	archsw.arch_copyin(s, a, strlen(s) + 1);\
203    a += roundup(strlen(s) + 1, sizeof(u_long));\
204}
205
206#define	MOD_NAME(a, s, c)	MOD_STR(MODINFO_NAME, a, s, c)
207#define	MOD_TYPE(a, s, c)	MOD_STR(MODINFO_TYPE, a, s, c)
208#define	MOD_ARGS(a, s, c)	MOD_STR(MODINFO_ARGS, a, s, c)
209
210#define	MOD_VAR(t, a, s, c) {			\
211    COPY32(t, a, c);				\
212    COPY32(sizeof(s), a, c);			\
213    if (c)					\
214	archsw.arch_copyin(&s, a, sizeof(s));	\
215    a += roundup(sizeof(s), sizeof(u_long));	\
216}
217
218#define	MOD_ADDR(a, s, c)	MOD_VAR(MODINFO_ADDR, a, s, c)
219#define	MOD_SIZE(a, s, c)	MOD_VAR(MODINFO_SIZE, a, s, c)
220
221#define	MOD_METADATA(a, mm, c) {		\
222    COPY32(MODINFO_METADATA | mm->md_type, a, c);\
223    COPY32(mm->md_size, a, c);			\
224    if (c)					\
225	archsw.arch_copyin(mm->md_data, a, mm->md_size);\
226    a += roundup(mm->md_size, sizeof(u_long));	\
227}
228
229#define	MOD_END(a, c) {				\
230    COPY32(MODINFO_END, a, c);			\
231    COPY32(0, a, c);				\
232}
233
234static vm_offset_t
235md_copymodules(vm_offset_t addr)
236{
237	struct preloaded_file	*fp;
238	struct file_metadata	*md;
239	int			c;
240	vm_offset_t a;
241
242	c = addr != 0;
243	/* start with the first module on the list, should be the kernel */
244	for (fp = file_findfile(NULL, NULL); fp != NULL; fp = fp->f_next) {
245
246		MOD_NAME(addr, fp->f_name, c);	/* this field must be first */
247		MOD_TYPE(addr, fp->f_type, c);
248		if (fp->f_args)
249			MOD_ARGS(addr, fp->f_args, c);
250		a = fp->f_addr - __elfN(relocation_offset);
251		MOD_ADDR(addr, a, c);
252		MOD_SIZE(addr, fp->f_size, c);
253		for (md = fp->f_metadata; md != NULL; md = md->md_next) {
254			if (!(md->md_type & MODINFOMD_NOCOPY))
255				MOD_METADATA(addr, md, c);
256		}
257	}
258	MOD_END(addr, c);
259	return(addr);
260}
261
262/*
263 * Load the information expected by a kernel.
264 *
265 * - The 'boothowto' argument is constructed
266 * - The 'bootdev' argument is constructed
267 * - The kernel environment is copied into kernel space.
268 * - Module metadata are formatted and placed in kernel space.
269 */
270int
271md_load(char *args, vm_offset_t *modulep)
272{
273	struct preloaded_file	*kfp, *bfp;
274	struct preloaded_file	*xp;
275	struct file_metadata	*md;
276	struct bootinfo		*bip;
277	vm_offset_t		kernend;
278	vm_offset_t		addr;
279	vm_offset_t		envp;
280	vm_offset_t		size;
281	vm_offset_t		vaddr;
282#if defined(LOADER_FDT_SUPPORT)
283	vm_offset_t		dtbp;
284	int			dtb_size;
285#endif
286	char			*rootdevname;
287	int			howto;
288	int			i;
289
290	/*
291	 * These metadata addreses must be converted for kernel after
292	 * relocation.
293	 */
294	uint32_t		mdt[] = {
295	    MODINFOMD_SSYM, MODINFOMD_ESYM, MODINFOMD_KERNEND,
296	    MODINFOMD_ENVP,
297#if defined(LOADER_FDT_SUPPORT)
298	    MODINFOMD_DTBP
299#endif
300	};
301
302	howto = md_getboothowto(args);
303
304	/*
305	 * Allow the environment variable 'rootdev' to override the supplied
306	 * device. This should perhaps go to MI code and/or have $rootdev
307	 * tested/set by MI code before launching the kernel.
308	 */
309	rootdevname = getenv("rootdev");
310	if (rootdevname == NULL)
311		rootdevname = getenv("currdev");
312	/* Try reading the /etc/fstab file to select the root device */
313	getrootmount(rootdevname);
314
315	/* Find the last module in the chain */
316	addr = 0;
317	for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
318		if (addr < (xp->f_addr + xp->f_size))
319			addr = xp->f_addr + xp->f_size;
320	}
321	/* Pad to a page boundary */
322	addr = roundup(addr, PAGE_SIZE);
323
324	/* Copy our environment */
325	envp = addr;
326	addr = md_copyenv(addr);
327
328	/* Pad to a page boundary */
329	addr = roundup(addr, PAGE_SIZE);
330
331#if defined(LOADER_FDT_SUPPORT)
332	/* Handle device tree blob */
333	dtbp = addr;
334	dtb_size = fdt_copy(addr);
335
336	/* Pad to a page boundary */
337	if (dtb_size)
338		addr += roundup(dtb_size, PAGE_SIZE);
339#endif
340
341	kernend = 0;
342	kfp = file_findfile(NULL, "elf32 kernel");
343	if (kfp == NULL)
344		kfp = file_findfile(NULL, "elf kernel");
345	if (kfp == NULL)
346		panic("can't find kernel file");
347	file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
348	file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
349
350#if defined(LOADER_FDT_SUPPORT)
351	if (dtb_size)
352		file_addmetadata(kfp, MODINFOMD_DTBP, sizeof dtbp, &dtbp);
353	else
354		pager_output("WARNING! Trying to fire up the kernel, but no "
355		    "device tree blob found!\n");
356#endif
357
358	file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
359
360	/* Figure out the size and location of the metadata */
361	*modulep = addr;
362	size = md_copymodules(0);
363	kernend = roundup(addr + size, PAGE_SIZE);
364
365	/* Provide MODINFOMD_KERNEND */
366	md = file_findmetadata(kfp, MODINFOMD_KERNEND);
367	bcopy(&kernend, md->md_data, sizeof kernend);
368
369	/* Convert addresses to the final VA */
370	*modulep -= __elfN(relocation_offset);
371
372	/* Do relocation fixup on metadata of each module. */
373	for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
374		for (i = 0; i < sizeof mdt / sizeof mdt[0]; i++) {
375			md = file_findmetadata(xp, mdt[i]);
376			if (md) {
377				bcopy(md->md_data, &vaddr, sizeof vaddr);
378				vaddr -= __elfN(relocation_offset);
379				bcopy(&vaddr, md->md_data, sizeof vaddr);
380			}
381		}
382	}
383
384	/* Only now copy actual modules and metadata */
385	(void)md_copymodules(addr);
386
387	return (0);
388}
389