xref: /netbsd/sys/dev/kloader.c (revision 30bb6193)
1 /*	$NetBSD: kloader.c,v 1.32 2021/10/11 14:25:05 rin Exp $	*/
2 
3 /*-
4  * Copyright (c) 2001, 2002, 2004 The NetBSD Foundation, Inc.
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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
26  * POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __KERNEL_RCSID(0, "$NetBSD: kloader.c,v 1.32 2021/10/11 14:25:05 rin Exp $");
31 
32 #include "debug_kloader.h"
33 
34 #include <sys/param.h>
35 #include <sys/fcntl.h>
36 #include <sys/kmem.h>
37 #include <sys/namei.h>
38 #include <sys/proc.h>
39 #include <sys/systm.h>
40 #include <sys/vnode.h>
41 
42 #define	ELFSIZE	32
43 #include <sys/exec_elf.h>
44 
45 #include <uvm/uvm_extern.h>
46 
47 #include <machine/kloader.h>
48 
49 #define	PRINTF(fmt, args...)	printf("kloader: " fmt, ##args)
50 
51 #ifdef KLOADER_DEBUG
52 int	kloader_debug = 1;
53 #define	DPRINTF(fmt, args...)						\
54 	if (kloader_debug)						\
55 		printf("%s: " fmt, __func__ , ##args)
56 #define	_DPRINTF(fmt, args...)						\
57 	if (kloader_debug)						\
58 		printf(fmt, ##args)
59 #define	DPRINTFN(n, fmt, args...)					\
60 	if (kloader_debug > (n))					\
61 		printf("%s: " fmt, __func__ , ##args)
62 #define	_DPRINTFN(n, fmt, args...)					\
63 	if (kloader_debug > (n))					\
64 		printf(fmt, ##args)
65 #define	STATIC
66 #else
67 #define	DPRINTF(fmt, args...)		((void)0)
68 #define	_DPRINTF(fmt, args...)		((void)0)
69 #define	DPRINTFN(n, fmt, args...)	((void)0)
70 #define	_DPRINTFN(n, fmt, args...)	((void)0)
71 #define	STATIC	static
72 #endif
73 
74 struct kloader {
75 	struct pglist pg_head;
76 	struct vm_page *cur_pg;		/* XXX use bus_dma(9) */
77 	struct kloader_page_tag *cur_tag;
78 	struct vnode *vp;
79 	struct kloader_page_tag *tagstart;
80 	struct kloader_bootinfo *bootinfo;
81 	struct kloader_bootinfo *rebootinfo;
82 	vaddr_t loader_sp;
83 	kloader_bootfunc_t *loader;
84 	int setuped;
85 	int called;
86 	struct kloader_ops *ops;
87 };
88 
89 #define	BUCKET_SIZE	(PAGE_SIZE - sizeof(struct kloader_page_tag))
90 #define	KLOADER_LWP	(&lwp0)
91 STATIC struct kloader kloader;
92 
93 #define	ROUND4(x)	(((x) + 3) & ~3)
94 
95 STATIC int kloader_load(void);
96 
97 STATIC int kloader_alloc_memory(size_t);
98 STATIC struct kloader_page_tag *kloader_get_tag(vaddr_t);
99 STATIC void kloader_from_file(vaddr_t, off_t, size_t);
100 STATIC void kloader_copy(vaddr_t, const void *, size_t);
101 STATIC void kloader_zero(vaddr_t, size_t);
102 
103 STATIC void kloader_load_segment(Elf_Phdr *);
104 
105 STATIC struct vnode *kloader_open(const char *);
106 STATIC void kloader_close(void);
107 STATIC int kloader_read(size_t, size_t, void *);
108 
109 #ifdef KLOADER_DEBUG
110 STATIC void kloader_pagetag_dump(void);
111 #endif
112 
113 void
__kloader_reboot_setup(struct kloader_ops * ops,const char * filename)114 __kloader_reboot_setup(struct kloader_ops *ops, const char *filename)
115 {
116 
117 	if (kloader.bootinfo == NULL) {
118 		PRINTF("No bootinfo.\n");
119 		return;
120 	}
121 
122 	if (ops == NULL || ops->jump == NULL || ops->boot == NULL) {
123 		PRINTF("No boot operations.\n");
124 		return;
125 	}
126 	kloader.ops = ops;
127 
128 	if (kloader.called++ == 0) {
129 		PRINTF("kernel file name: %s\n", filename);
130 		kloader.vp = kloader_open(filename);
131 		if (kloader.vp == NULL)
132 			return;
133 
134 		if (kloader_load() == 0) {
135 			kloader.setuped = TRUE;
136 #ifdef KLOADER_DEBUG
137 			kloader_pagetag_dump();
138 #endif
139 		}
140 		kloader_close();
141 	} else {
142 		/* Fatal case. reboot from DDB etc. */
143 		kloader_reboot();
144 	}
145 }
146 
147 
148 void
kloader_reboot(void)149 kloader_reboot(void)
150 {
151 
152 	if (kloader.setuped) {
153 		PRINTF("Rebooting...\n");
154 		(*kloader.ops->jump)(kloader.loader, kloader.loader_sp,
155 		    kloader.rebootinfo, kloader.tagstart);
156 	}
157 
158 	if (kloader.ops->reset != NULL) {
159 		PRINTF("Resetting...\n");
160 		(*kloader.ops->reset)();
161 	}
162 	while (/*CONSTCOND*/1)
163 		continue;
164 	/* NOTREACHED */
165 }
166 
167 
168 int
kloader_load(void)169 kloader_load(void)
170 {
171 	Elf_Ehdr eh;
172 	Elf_Phdr *ph, *p;
173 	Elf_Shdr *sh;
174 	Elf_Addr entry;
175 	vaddr_t kv;
176 	size_t sz;
177 	size_t phsz, shsz, shstrsz;
178 	char *shstrtab;
179 	int symndx, strndx;
180 	size_t ksymsz;
181 	struct kloader_bootinfo nbi; /* new boot info */
182 	char *oldbuf, *newbuf;
183 	char **ap;
184 	int i;
185 
186 	ph = NULL;
187 	sh = NULL;
188 	shstrtab = NULL;
189 
190 	/* read kernel's ELF header */
191 	kloader_read(0, sizeof(Elf_Ehdr), &eh);
192 
193 	if (eh.e_ident[EI_MAG0] != ELFMAG0 ||
194 	    eh.e_ident[EI_MAG1] != ELFMAG1 ||
195 	    eh.e_ident[EI_MAG2] != ELFMAG2 ||
196 	    eh.e_ident[EI_MAG3] != ELFMAG3) {
197 		PRINTF("not an ELF file\n");
198 		goto err;
199 	}
200 
201 	/* read program headers */
202 	phsz = eh.e_phentsize * eh.e_phnum;
203 	if ((ph = kmem_alloc(phsz, KM_NOSLEEP)) == NULL) {
204 		PRINTF("can't allocate program header table.\n");
205 		goto err;
206 	}
207 	if (kloader_read(eh.e_phoff, phsz, ph) != 0) {
208 		PRINTF("program header read error.\n");
209 		goto err;
210 	}
211 
212 	/* read section headers */
213 	shsz = eh.e_shentsize * eh.e_shnum;
214 	if ((sh = kmem_alloc(shsz, KM_NOSLEEP)) == NULL) {
215 		PRINTF("can't allocate section header table.\n");
216 		goto err;
217 	}
218 	if (kloader_read(eh.e_shoff, shsz, sh) != 0) {
219 		PRINTF("section header read error.\n");
220 		goto err;
221 	}
222 
223 	/* read section names */
224 	shstrsz = ROUND4(sh[eh.e_shstrndx].sh_size);
225 	shstrtab = kmem_alloc(shstrsz, KM_NOSLEEP);
226 	if (shstrtab == NULL) {
227 		PRINTF("unable to allocate memory for .shstrtab\n");
228 		goto err;
229 	}
230 	DPRINTF("reading 0x%x bytes of .shstrtab at 0x%x\n",
231 	    sh[eh.e_shstrndx].sh_size, sh[eh.e_shstrndx].sh_offset);
232 	kloader_read(sh[eh.e_shstrndx].sh_offset, sh[eh.e_shstrndx].sh_size,
233 	    shstrtab);
234 
235 	/* save entry point, code to construct symbol table overwrites it */
236 	entry = eh.e_entry;
237 
238 	/*
239 	 * Calculate memory size
240 	 */
241 	sz = 0;
242 
243 	/* loadable segments */
244 	for (i = 0; i < eh.e_phnum; i++) {
245 		if (ph[i].p_type == PT_LOAD) {
246 			DPRINTF("segment %d size = file 0x%x memory 0x%x\n",
247 			    i, ph[i].p_filesz, ph[i].p_memsz);
248 #ifdef KLOADER_ZERO_BSS
249 			sz += round_page(ph[i].p_memsz);
250 #else
251 			sz += round_page(ph[i].p_filesz);
252 #endif
253 			sz += PAGE_SIZE; /* compensate for partial last tag */
254 		}
255 	}
256 
257 	if (sz == 0)		/* nothing to load? */
258 		goto err;
259 
260 	/* symbols/strings sections */
261 	symndx = strndx = -1;
262 	for (i = 0; i < eh.e_shnum; i++) {
263 		if (strcmp(shstrtab + sh[i].sh_name, ".symtab") == 0)
264 			symndx = i;
265 		else if (strcmp(shstrtab + sh[i].sh_name, ".strtab") == 0)
266 			strndx = i;
267 		else if (i != eh.e_shstrndx) {
268 			/* while here, mark all other sections as unused */
269 			sh[i].sh_type = SHT_NULL;
270 			sh[i].sh_offset = 0;
271 		}
272 	}
273 
274 	if (symndx < 0 || strndx < 0) {
275 		if (symndx < 0)
276 			PRINTF("no .symtab section\n");
277 		if (strndx < 0)
278 			PRINTF("no .strtab section\n");
279 		ksymsz = SELFMAG; /* just a bad magic */
280 	} else {
281 		ksymsz = sizeof(Elf_Ehdr)
282 		    + eh.e_shentsize * eh.e_shnum
283 		    + shstrsz		/* rounded to 4 bytes */
284 		    + sh[symndx].sh_size
285 		    + sh[strndx].sh_size;
286 		DPRINTF("ksyms size = 0x%zx\n", ksymsz);
287 	}
288 	sz += ROUND4(ksymsz);
289 
290 	/* boot info for the new kernel */
291 	sz += sizeof(struct kloader_bootinfo);
292 
293 	/* get memory for new kernel */
294 	if (kloader_alloc_memory(sz) != 0)
295 		goto err;
296 
297 	/*
298 	 * Copy new kernel in.
299 	 */
300 	kv = 0;			/* XXX: -Wuninitialized */
301 	for (i = 0, p = ph; i < eh.e_phnum; i++, p++) {
302 		if (p->p_type == PT_LOAD) {
303 			kloader_load_segment(p);
304 			kv = p->p_vaddr + ROUND4(p->p_memsz);
305 		}
306 	}
307 
308 	/*
309 	 * Construct symbol table for ksyms.
310 	 */
311 	if (symndx < 0 || strndx < 0) {
312 		kloader_zero(kv, SELFMAG);
313 		kv += SELFMAG;
314 	} else {
315 		Elf_Off eoff;
316 		off_t symoff, stroff;
317 
318 		/* save offsets of .symtab and .strtab before we change them */
319 		symoff = sh[symndx].sh_offset;
320 		stroff = sh[strndx].sh_offset;
321 
322 		/* no loadable segments */
323 		eh.e_entry = 0;
324 		eh.e_phnum = 0;
325 		eh.e_phoff = 0;
326 
327 		/* change offsets to reflect new layout */
328 		eoff = sizeof(Elf_Ehdr);
329 		eh.e_shoff = eoff;
330 
331 		eoff += eh.e_shentsize * eh.e_shnum;
332 		sh[eh.e_shstrndx].sh_offset = eoff;
333 
334 		eoff += shstrsz;
335 		sh[symndx].sh_offset = eoff;
336 
337 		eoff += sh[symndx].sh_size;
338 		sh[strndx].sh_offset = eoff;
339 
340 		/* local copies massaged, can serve them now */
341 		DPRINTF("ksyms ELF header\n");
342 		kloader_copy(kv, &eh, sizeof(Elf_Ehdr));
343 		kv += sizeof(Elf_Ehdr);
344 
345 		DPRINTF("ksyms section headers\n");
346 		kloader_copy(kv, sh, eh.e_shentsize * eh.e_shnum);
347 		kv += eh.e_shentsize * eh.e_shnum;
348 
349 		DPRINTF("ksyms .shstrtab\n");
350 		kloader_copy(kv, shstrtab, shstrsz);
351 		kv += shstrsz;
352 
353 		DPRINTF("ksyms .symtab\n");
354 		kloader_from_file(kv, symoff, sh[symndx].sh_size);
355 		kv += sh[symndx].sh_size;
356 
357 		DPRINTF("ksyms .strtab\n");
358 		kloader_from_file(kv, stroff, ROUND4(sh[strndx].sh_size));
359 		kv += ROUND4(sh[strndx].sh_size);
360 	}
361 
362 	/*
363 	 * Create boot info to pass to the new kernel.
364 	 * All pointers in it are *not* valid until the new kernel runs!
365 	 */
366 
367 	/* get a private copy of current bootinfo to vivisect */
368 	memcpy(&nbi, kloader.bootinfo, sizeof(struct kloader_bootinfo));
369 
370 	/* new kernel entry point */
371 	nbi.entry = entry;
372 
373 	/* where args currently are, see kloader_bootinfo_set() */
374 	oldbuf = &kloader.bootinfo->_argbuf[0];
375 
376 	/* where args *will* be after boot code copied them */
377 	newbuf = (char *)(void *)kv
378 	    + offsetof(struct kloader_bootinfo, _argbuf);
379 
380 	DPRINTF("argv: old %p -> new %p\n", oldbuf, newbuf);
381 
382 	/* not a valid pointer in this kernel! */
383 	nbi.argv = (void *)newbuf;
384 
385 	/* local copy that we populate with new (not yet valid) pointers */
386 	ap = (char **)(void *)nbi._argbuf;
387 
388 	for (i = 0; i < kloader.bootinfo->argc; ++i) {
389 		DPRINTFN(1, " [%d]: %p -> ", i, kloader.bootinfo->argv[i]);
390 		ap[i] = newbuf +
391 		    (kloader.bootinfo->argv[i] - oldbuf);
392 		_DPRINTFN(1, "%p\n", ap[i]);
393 	}
394 
395 	/* arrange for the new bootinfo to get copied */
396 	DPRINTF("bootinfo\n");
397 	kloader_copy(kv, &nbi, sizeof(struct kloader_bootinfo));
398 
399 	/* will be valid by the time the new kernel starts */
400 	kloader.rebootinfo = (void *)kv;
401 	/* kv += sizeof(struct kloader_bootinfo); */
402 
403 	/*
404 	 * Copy loader code
405 	 */
406 	KDASSERT(kloader.cur_pg);
407 	kloader.loader = (void *)PG_VADDR(kloader.cur_pg);
408 	memcpy(kloader.loader, kloader.ops->boot, PAGE_SIZE);
409 
410 	/* loader stack starts at the bottom of that page */
411 	kloader.loader_sp = (vaddr_t)kloader.loader + PAGE_SIZE;
412 
413 	DPRINTF("[loader] addr=%p sp=%p [kernel] entry=%p\n",
414 	    kloader.loader, (void *)kloader.loader_sp, (void *)nbi.entry);
415 
416 	return (0);
417  err:
418 	if (ph != NULL)
419 		kmem_free(ph, phsz);
420 	if (sh != NULL)
421 		kmem_free(sh, shsz);
422 	if (shstrtab != NULL)
423 		kmem_free(shstrtab, shstrsz);
424 
425 	return 1;
426 }
427 
428 
429 int
kloader_alloc_memory(size_t sz)430 kloader_alloc_memory(size_t sz)
431 {
432 	int n, error;
433 
434 	n = (sz + BUCKET_SIZE - 1) / BUCKET_SIZE	/* kernel &co */
435 	    + 1;					/* 2nd loader */
436 
437 	error = uvm_pglistalloc(n * PAGE_SIZE, avail_start, avail_end,
438 	    PAGE_SIZE, 0, &kloader.pg_head, n, 0);
439 	if (error) {
440 		PRINTF("can't allocate memory.\n");
441 		return (1);
442 	}
443 	DPRINTF("allocated %d pages.\n", n);
444 
445 	kloader.cur_pg = TAILQ_FIRST(&kloader.pg_head);
446 	kloader.tagstart = (void *)PG_VADDR(kloader.cur_pg);
447 	kloader.cur_tag = NULL;
448 
449 	return (0);
450 }
451 
452 
453 struct kloader_page_tag *
kloader_get_tag(vaddr_t dst)454 kloader_get_tag(vaddr_t dst)
455 {
456 	struct vm_page *pg;
457 	vaddr_t addr;
458 	struct kloader_page_tag *tag;
459 
460 	tag = kloader.cur_tag;
461 	if (tag != NULL		/* has tag */
462 	    && tag->sz < BUCKET_SIZE /* that has free space */
463 	    && tag->dst + tag->sz == dst) /* and new data are contiguous */
464 	{
465 		DPRINTFN(1, "current tag %x/%x ok\n", tag->dst, tag->sz);
466 		return (tag);
467 	}
468 
469 	pg = kloader.cur_pg;
470 	KDASSERT(pg != NULL);
471 	kloader.cur_pg = TAILQ_NEXT(pg, pageq.queue);
472 
473 	addr = PG_VADDR(pg);
474 	tag = (void *)addr;
475 
476 	/*
477 	 * 2nd loader uses simple word-by-word copy, so destination
478 	 * address of a tag must be properly aligned.
479 	 */
480 	KASSERT(ALIGNED_POINTER(dst, register_t));
481 
482 	tag->src = addr + sizeof(struct kloader_page_tag);
483 	tag->dst = dst;
484 	tag->sz = 0;
485 	tag->next = 0;	/* Terminate. this member may overwrite after. */
486 	if (kloader.cur_tag)
487 		kloader.cur_tag->next = addr;
488 	kloader.cur_tag = tag;
489 
490 	return (tag);
491 }
492 
493 
494 /*
495  * Operations to populate kloader_page_tag's with data.
496  */
497 
498 void
kloader_from_file(vaddr_t dst,off_t ofs,size_t sz)499 kloader_from_file(vaddr_t dst, off_t ofs, size_t sz)
500 {
501 	struct kloader_page_tag *tag;
502 	size_t freesz;
503 
504 	while (sz > 0) {
505 		tag = kloader_get_tag(dst);
506 		KDASSERT(tag != NULL);
507 		freesz = BUCKET_SIZE - tag->sz;
508 		if (freesz > sz)
509 			freesz = sz;
510 
511 		DPRINTFN(1, "0x%08"PRIxVADDR" + 0x%zx <- 0x%lx\n", dst, freesz,
512 		    (unsigned long)ofs);
513 		kloader_read(ofs, freesz, (void *)(tag->src + tag->sz));
514 
515 		tag->sz += freesz;
516 		sz -= freesz;
517 		ofs += freesz;
518 		dst += freesz;
519 	}
520 }
521 
522 
523 void
kloader_copy(vaddr_t dst,const void * src,size_t sz)524 kloader_copy(vaddr_t dst, const void *src, size_t sz)
525 {
526 	struct kloader_page_tag *tag;
527 	size_t freesz;
528 
529 	while (sz > 0) {
530 		tag = kloader_get_tag(dst);
531 		KDASSERT(tag != NULL);
532 		freesz = BUCKET_SIZE - tag->sz;
533 		if (freesz > sz)
534 			freesz = sz;
535 
536 		DPRINTFN(1, "0x%08"PRIxVADDR" + 0x%zx <- %p\n", dst, freesz, src);
537 		memcpy((void *)(tag->src + tag->sz), src, freesz);
538 
539 		tag->sz += freesz;
540 		sz -= freesz;
541 		src = (const char *)src + freesz;
542 		dst += freesz;
543 	}
544 }
545 
546 
547 void
kloader_zero(vaddr_t dst,size_t sz)548 kloader_zero(vaddr_t dst, size_t sz)
549 {
550 	struct kloader_page_tag *tag;
551 	size_t freesz;
552 
553 	while (sz > 0) {
554 		tag = kloader_get_tag(dst);
555 		KDASSERT(tag != NULL);
556 		freesz = BUCKET_SIZE - tag->sz;
557 		if (freesz > sz)
558 			freesz = sz;
559 
560 		DPRINTFN(1, "0x%08"PRIxVADDR" + 0x%zx\n", dst, freesz);
561 		memset((void *)(tag->src + tag->sz), 0, freesz);
562 
563 		tag->sz += freesz;
564 		sz -= freesz;
565 		dst += freesz;
566 	}
567 }
568 
569 
570 void
kloader_load_segment(Elf_Phdr * p)571 kloader_load_segment(Elf_Phdr *p)
572 {
573 
574 	DPRINTF("memory 0x%08x 0x%x <- file 0x%x 0x%x\n",
575 	    p->p_vaddr, p->p_memsz, p->p_offset, p->p_filesz);
576 
577 	kloader_from_file(p->p_vaddr, p->p_offset, p->p_filesz);
578 #ifdef KLOADER_ZERO_BSS
579 	kloader_zero(p->p_vaddr + p->p_filesz, p->p_memsz - p->p_filesz);
580 #endif
581 }
582 
583 
584 /*
585  * file access
586  */
587 struct vnode *
kloader_open(const char * filename)588 kloader_open(const char *filename)
589 {
590 	struct pathbuf *pb;
591 	struct nameidata nid;
592 	struct vnode *vp;
593 	int error;
594 
595 	pb = pathbuf_create(filename);
596 	if (pb == NULL) {
597 		PRINTF("%s: pathbuf_create failed\n", filename);
598 		return (NULL);
599 	}
600 
601 	/*
602 	 * XXX why does this call both namei and vn_open?
603 	 */
604 
605 	NDINIT(&nid, LOOKUP, FOLLOW, pb);
606 	error = namei(&nid);
607 	if (error != 0) {
608 		PRINTF("%s: namei failed, errno=%d\n", filename, error);
609 		pathbuf_destroy(pb);
610 		return (NULL);
611 	}
612 
613 	error = vn_open(NULL, pb, 0, FREAD, 0, &vp, NULL, NULL);
614 	if (error != 0) {
615 		PRINTF("%s: open failed, errno=%d\n", filename, error);
616 		pathbuf_destroy(pb);
617 		return (NULL);
618 	}
619 
620 	pathbuf_destroy(pb);
621 	return vp;
622 }
623 
624 void
kloader_close(void)625 kloader_close(void)
626 {
627 	struct lwp *l = KLOADER_LWP;
628 	struct vnode *vp = kloader.vp;
629 
630 	VOP_UNLOCK(vp);
631 	vn_close(vp, FREAD, l->l_cred);
632 }
633 
634 int
kloader_read(size_t ofs,size_t size,void * buf)635 kloader_read(size_t ofs, size_t size, void *buf)
636 {
637 	struct lwp *l = KLOADER_LWP;
638 	struct vnode *vp = kloader.vp;
639 	size_t resid;
640 	int error;
641 
642 	error = vn_rdwr(UIO_READ, vp, buf, size, ofs, UIO_SYSSPACE,
643 	    IO_NODELOCKED | IO_SYNC, l->l_cred, &resid, NULL);
644 
645 	if (error)
646 		PRINTF("read error.\n");
647 
648 	return (error);
649 }
650 
651 
652 /*
653  * bootinfo
654  */
655 void
kloader_bootinfo_set(struct kloader_bootinfo * kbi,int argc,char * argv[],struct bootinfo * bi,int printok)656 kloader_bootinfo_set(struct kloader_bootinfo *kbi, int argc, char *argv[],
657     struct bootinfo *bi, int printok)
658 {
659 	char *p, *pend, *buf;
660 	int i;
661 
662 	kloader.bootinfo = kbi;
663 	buf = kbi->_argbuf;
664 	if (bi != NULL)
665 		memcpy(&kbi->bootinfo, bi, sizeof(struct bootinfo));
666 	kbi->argc = argc;
667 	kbi->argv = (char **)buf;
668 
669 	p = &buf[argc * sizeof(char **)];
670 	pend = &buf[KLOADER_KERNELARGS_MAX - 1];
671 
672 	for (i = 0; i < argc; i++) {
673 		char *q = argv[i];
674 		int len = strlen(q) + 1;
675 		if ((p + len) > pend) {
676 			kloader.bootinfo = NULL;
677 			if (printok)
678 				PRINTF("buffer insufficient.\n");
679 			return;
680 		}
681 		kbi->argv[i] = p;
682 		memcpy(p, q, len);
683 		p += len;
684 	}
685 }
686 
687 
688 #ifdef KLOADER_DEBUG
689 void
kloader_pagetag_dump(void)690 kloader_pagetag_dump(void)
691 {
692 	struct kloader_page_tag *tag = kloader.tagstart;
693 	struct kloader_page_tag *p, *op;
694 	bool print;
695 	int i, n;
696 
697 	p = tag;
698 	op = NULL;
699 	i = 0, n = 15;
700 
701 	PRINTF("[page tag chain]\n");
702 	do  {
703 		print = FALSE;
704 		if (i < n)
705 			print = TRUE;
706 		if ((uint32_t)p & 3) {
707 			printf("tag alignment error\n");
708 			break;
709 		}
710 		if ((p->src & 3) || (p->dst & 3)) {
711 			printf("data alignment error.\n");
712 			print = TRUE;
713 		}
714 
715 		if (print) {
716 			printf("[%2d] next 0x%08x src 0x%08x dst 0x%08x"
717 			    " sz 0x%x\n", i, p->next, p->src, p->dst, p->sz);
718 		} else if (i == n) {
719 			printf("[...]\n");
720 		}
721 		op = p;
722 		i++;
723 	} while ((p = (struct kloader_page_tag *)(p->next)) != 0);
724 
725 	if (op != NULL)
726 		printf("[%d(last)] next 0x%08x src 0x%08x dst 0x%08x sz 0x%x\n",
727 		    i - 1, op->next, op->src, op->dst, op->sz);
728 }
729 
730 #endif /* KLOADER_DEBUG */
731