1 /*
2 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 *
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
22 */
23
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
25
26 /**
27 * @file
28 *
29 * Linux bzImage image format
30 *
31 */
32
33 #include <stdint.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <errno.h>
37 #include <assert.h>
38 #include <realmode.h>
39 #include <bzimage.h>
40 #include <initrd.h>
41 #include <ipxe/uaccess.h>
42 #include <ipxe/image.h>
43 #include <ipxe/segment.h>
44 #include <ipxe/init.h>
45 #include <ipxe/cpio.h>
46 #include <ipxe/features.h>
47
48 FEATURE ( FEATURE_IMAGE, "bzImage", DHCP_EB_FEATURE_BZIMAGE, 1 );
49
50 /**
51 * bzImage context
52 */
53 struct bzimage_context {
54 /** Boot protocol version */
55 unsigned int version;
56 /** Real-mode kernel portion load segment address */
57 unsigned int rm_kernel_seg;
58 /** Real-mode kernel portion load address */
59 userptr_t rm_kernel;
60 /** Real-mode kernel portion file size */
61 size_t rm_filesz;
62 /** Real-mode heap top (offset from rm_kernel) */
63 size_t rm_heap;
64 /** Command line (offset from rm_kernel) */
65 size_t rm_cmdline;
66 /** Command line maximum length */
67 size_t cmdline_size;
68 /** Real-mode kernel portion total memory size */
69 size_t rm_memsz;
70 /** Non-real-mode kernel portion load address */
71 userptr_t pm_kernel;
72 /** Non-real-mode kernel portion file and memory size */
73 size_t pm_sz;
74 /** Video mode */
75 unsigned int vid_mode;
76 /** Memory limit */
77 uint64_t mem_limit;
78 /** Initrd address */
79 physaddr_t ramdisk_image;
80 /** Initrd size */
81 physaddr_t ramdisk_size;
82
83 /** Command line magic block */
84 struct bzimage_cmdline cmdline_magic;
85 /** bzImage header */
86 struct bzimage_header bzhdr;
87 };
88
89 /**
90 * Parse bzImage header
91 *
92 * @v image bzImage file
93 * @v bzimg bzImage context
94 * @v src bzImage to parse
95 * @ret rc Return status code
96 */
bzimage_parse_header(struct image * image,struct bzimage_context * bzimg,userptr_t src)97 static int bzimage_parse_header ( struct image *image,
98 struct bzimage_context *bzimg,
99 userptr_t src ) {
100 unsigned int syssize;
101 int is_bzimage;
102
103 /* Sanity check */
104 if ( image->len < ( BZI_HDR_OFFSET + sizeof ( bzimg->bzhdr ) ) ) {
105 DBGC ( image, "bzImage %p too short for kernel header\n",
106 image );
107 return -ENOEXEC;
108 }
109
110 /* Read in header structures */
111 memset ( bzimg, 0, sizeof ( *bzimg ) );
112 copy_from_user ( &bzimg->cmdline_magic, src, BZI_CMDLINE_OFFSET,
113 sizeof ( bzimg->cmdline_magic ) );
114 copy_from_user ( &bzimg->bzhdr, src, BZI_HDR_OFFSET,
115 sizeof ( bzimg->bzhdr ) );
116
117 /* Calculate size of real-mode portion */
118 bzimg->rm_filesz = ( ( ( bzimg->bzhdr.setup_sects ?
119 bzimg->bzhdr.setup_sects : 4 ) + 1 ) << 9 );
120 if ( bzimg->rm_filesz > image->len ) {
121 DBGC ( image, "bzImage %p too short for %zd byte of setup\n",
122 image, bzimg->rm_filesz );
123 return -ENOEXEC;
124 }
125 bzimg->rm_memsz = BZI_ASSUMED_RM_SIZE;
126
127 /* Calculate size of protected-mode portion */
128 bzimg->pm_sz = ( image->len - bzimg->rm_filesz );
129 syssize = ( ( bzimg->pm_sz + 15 ) / 16 );
130
131 /* Check for signatures and determine version */
132 if ( bzimg->bzhdr.boot_flag != BZI_BOOT_FLAG ) {
133 DBGC ( image, "bzImage %p missing 55AA signature\n", image );
134 return -ENOEXEC;
135 }
136 if ( bzimg->bzhdr.header == BZI_SIGNATURE ) {
137 /* 2.00+ */
138 bzimg->version = bzimg->bzhdr.version;
139 } else {
140 /* Pre-2.00. Check that the syssize field is correct,
141 * as a guard against accepting arbitrary binary data,
142 * since the 55AA check is pretty lax. Note that the
143 * syssize field is unreliable for protocols between
144 * 2.00 and 2.03 inclusive, so we should not always
145 * check this field.
146 */
147 bzimg->version = 0x0100;
148 if ( bzimg->bzhdr.syssize != syssize ) {
149 DBGC ( image, "bzImage %p bad syssize %x (expected "
150 "%x)\n", image, bzimg->bzhdr.syssize, syssize );
151 return -ENOEXEC;
152 }
153 }
154
155 /* Determine image type */
156 is_bzimage = ( ( bzimg->version >= 0x0200 ) ?
157 ( bzimg->bzhdr.loadflags & BZI_LOAD_HIGH ) : 0 );
158
159 /* Calculate load address of real-mode portion */
160 bzimg->rm_kernel_seg = ( is_bzimage ? 0x1000 : 0x9000 );
161 bzimg->rm_kernel = real_to_user ( bzimg->rm_kernel_seg, 0 );
162
163 /* Allow space for the stack and heap */
164 bzimg->rm_memsz += BZI_STACK_SIZE;
165 bzimg->rm_heap = bzimg->rm_memsz;
166
167 /* Allow space for the command line */
168 bzimg->rm_cmdline = bzimg->rm_memsz;
169 bzimg->rm_memsz += BZI_CMDLINE_SIZE;
170
171 /* Calculate load address of protected-mode portion */
172 bzimg->pm_kernel = phys_to_user ( is_bzimage ? BZI_LOAD_HIGH_ADDR
173 : BZI_LOAD_LOW_ADDR );
174
175 /* Extract video mode */
176 bzimg->vid_mode = bzimg->bzhdr.vid_mode;
177
178 /* Extract memory limit */
179 bzimg->mem_limit = ( ( bzimg->version >= 0x0203 ) ?
180 bzimg->bzhdr.initrd_addr_max : BZI_INITRD_MAX );
181
182 /* Extract command line size */
183 bzimg->cmdline_size = ( ( bzimg->version >= 0x0206 ) ?
184 bzimg->bzhdr.cmdline_size : BZI_CMDLINE_SIZE );
185
186 DBGC ( image, "bzImage %p version %04x RM %#lx+%#zx PM %#lx+%#zx "
187 "cmdlen %zd\n", image, bzimg->version,
188 user_to_phys ( bzimg->rm_kernel, 0 ), bzimg->rm_filesz,
189 user_to_phys ( bzimg->pm_kernel, 0 ), bzimg->pm_sz,
190 bzimg->cmdline_size );
191
192 return 0;
193 }
194
195 /**
196 * Update bzImage header in loaded kernel
197 *
198 * @v image bzImage file
199 * @v bzimg bzImage context
200 * @v dst bzImage to update
201 */
bzimage_update_header(struct image * image,struct bzimage_context * bzimg,userptr_t dst)202 static void bzimage_update_header ( struct image *image,
203 struct bzimage_context *bzimg,
204 userptr_t dst ) {
205
206 /* Set loader type */
207 if ( bzimg->version >= 0x0200 )
208 bzimg->bzhdr.type_of_loader = BZI_LOADER_TYPE_IPXE;
209
210 /* Set heap end pointer */
211 if ( bzimg->version >= 0x0201 ) {
212 bzimg->bzhdr.heap_end_ptr = ( bzimg->rm_heap - 0x200 );
213 bzimg->bzhdr.loadflags |= BZI_CAN_USE_HEAP;
214 }
215
216 /* Set command line */
217 if ( bzimg->version >= 0x0202 ) {
218 bzimg->bzhdr.cmd_line_ptr = user_to_phys ( bzimg->rm_kernel,
219 bzimg->rm_cmdline );
220 } else {
221 bzimg->cmdline_magic.magic = BZI_CMDLINE_MAGIC;
222 bzimg->cmdline_magic.offset = bzimg->rm_cmdline;
223 if ( bzimg->version >= 0x0200 )
224 bzimg->bzhdr.setup_move_size = bzimg->rm_memsz;
225 }
226
227 /* Set video mode */
228 bzimg->bzhdr.vid_mode = bzimg->vid_mode;
229
230 /* Set initrd address */
231 if ( bzimg->version >= 0x0200 ) {
232 bzimg->bzhdr.ramdisk_image = bzimg->ramdisk_image;
233 bzimg->bzhdr.ramdisk_size = bzimg->ramdisk_size;
234 }
235
236 /* Write out header structures */
237 copy_to_user ( dst, BZI_CMDLINE_OFFSET, &bzimg->cmdline_magic,
238 sizeof ( bzimg->cmdline_magic ) );
239 copy_to_user ( dst, BZI_HDR_OFFSET, &bzimg->bzhdr,
240 sizeof ( bzimg->bzhdr ) );
241
242 DBGC ( image, "bzImage %p vidmode %d\n", image, bzimg->vid_mode );
243 }
244
245 /**
246 * Parse kernel command line for bootloader parameters
247 *
248 * @v image bzImage file
249 * @v bzimg bzImage context
250 * @v cmdline Kernel command line
251 * @ret rc Return status code
252 */
bzimage_parse_cmdline(struct image * image,struct bzimage_context * bzimg,const char * cmdline)253 static int bzimage_parse_cmdline ( struct image *image,
254 struct bzimage_context *bzimg,
255 const char *cmdline ) {
256 char *vga;
257 char *mem;
258
259 /* Look for "vga=" */
260 if ( ( vga = strstr ( cmdline, "vga=" ) ) ) {
261 vga += 4;
262 if ( strcmp ( vga, "normal" ) == 0 ) {
263 bzimg->vid_mode = BZI_VID_MODE_NORMAL;
264 } else if ( strcmp ( vga, "ext" ) == 0 ) {
265 bzimg->vid_mode = BZI_VID_MODE_EXT;
266 } else if ( strcmp ( vga, "ask" ) == 0 ) {
267 bzimg->vid_mode = BZI_VID_MODE_ASK;
268 } else {
269 bzimg->vid_mode = strtoul ( vga, &vga, 0 );
270 if ( *vga && ( *vga != ' ' ) ) {
271 DBGC ( image, "bzImage %p strange \"vga=\""
272 "terminator '%c'\n", image, *vga );
273 }
274 }
275 }
276
277 /* Look for "mem=" */
278 if ( ( mem = strstr ( cmdline, "mem=" ) ) ) {
279 mem += 4;
280 bzimg->mem_limit = strtoul ( mem, &mem, 0 );
281 switch ( *mem ) {
282 case 'G':
283 case 'g':
284 bzimg->mem_limit <<= 10;
285 /* Fall through */
286 case 'M':
287 case 'm':
288 bzimg->mem_limit <<= 10;
289 /* Fall through */
290 case 'K':
291 case 'k':
292 bzimg->mem_limit <<= 10;
293 break;
294 case '\0':
295 case ' ':
296 break;
297 default:
298 DBGC ( image, "bzImage %p strange \"mem=\" "
299 "terminator '%c'\n", image, *mem );
300 break;
301 }
302 bzimg->mem_limit -= 1;
303 }
304
305 return 0;
306 }
307
308 /**
309 * Set command line
310 *
311 * @v image bzImage image
312 * @v bzimg bzImage context
313 * @v cmdline Kernel command line
314 */
bzimage_set_cmdline(struct image * image,struct bzimage_context * bzimg,const char * cmdline)315 static void bzimage_set_cmdline ( struct image *image,
316 struct bzimage_context *bzimg,
317 const char *cmdline ) {
318 size_t cmdline_len;
319
320 /* Copy command line down to real-mode portion */
321 cmdline_len = ( strlen ( cmdline ) + 1 );
322 if ( cmdline_len > bzimg->cmdline_size )
323 cmdline_len = bzimg->cmdline_size;
324 copy_to_user ( bzimg->rm_kernel, bzimg->rm_cmdline,
325 cmdline, cmdline_len );
326 DBGC ( image, "bzImage %p command line \"%s\"\n", image, cmdline );
327 }
328
329 /**
330 * Parse standalone image command line for cpio parameters
331 *
332 * @v image bzImage file
333 * @v cpio CPIO header
334 * @v cmdline Command line
335 */
bzimage_parse_cpio_cmdline(struct image * image,struct cpio_header * cpio,const char * cmdline)336 static void bzimage_parse_cpio_cmdline ( struct image *image,
337 struct cpio_header *cpio,
338 const char *cmdline ) {
339 char *arg;
340 char *end;
341 unsigned int mode;
342
343 /* Look for "mode=" */
344 if ( ( arg = strstr ( cmdline, "mode=" ) ) ) {
345 arg += 5;
346 mode = strtoul ( arg, &end, 8 /* Octal for file mode */ );
347 if ( *end && ( *end != ' ' ) ) {
348 DBGC ( image, "bzImage %p strange \"mode=\""
349 "terminator '%c'\n", image, *end );
350 }
351 cpio_set_field ( cpio->c_mode, ( 0100000 | mode ) );
352 }
353 }
354
355 /**
356 * Align initrd length
357 *
358 * @v len Length
359 * @ret len Length rounded up to INITRD_ALIGN
360 */
bzimage_align(size_t len)361 static inline size_t bzimage_align ( size_t len ) {
362
363 return ( ( len + INITRD_ALIGN - 1 ) & ~( INITRD_ALIGN - 1 ) );
364 }
365
366 /**
367 * Load initrd
368 *
369 * @v image bzImage image
370 * @v initrd initrd image
371 * @v address Address at which to load, or UNULL
372 * @ret len Length of loaded image, excluding zero-padding
373 */
bzimage_load_initrd(struct image * image,struct image * initrd,userptr_t address)374 static size_t bzimage_load_initrd ( struct image *image,
375 struct image *initrd,
376 userptr_t address ) {
377 char *filename = initrd->cmdline;
378 char *cmdline;
379 struct cpio_header cpio;
380 size_t offset;
381 size_t name_len;
382 size_t pad_len;
383
384 /* Do not include kernel image itself as an initrd */
385 if ( initrd == image )
386 return 0;
387
388 /* Create cpio header for non-prebuilt images */
389 if ( filename && filename[0] ) {
390 cmdline = strchr ( filename, ' ' );
391 name_len = ( ( cmdline ? ( ( size_t ) ( cmdline - filename ) )
392 : strlen ( filename ) ) + 1 /* NUL */ );
393 memset ( &cpio, '0', sizeof ( cpio ) );
394 memcpy ( cpio.c_magic, CPIO_MAGIC, sizeof ( cpio.c_magic ) );
395 cpio_set_field ( cpio.c_mode, 0100644 );
396 cpio_set_field ( cpio.c_nlink, 1 );
397 cpio_set_field ( cpio.c_filesize, initrd->len );
398 cpio_set_field ( cpio.c_namesize, name_len );
399 if ( cmdline ) {
400 bzimage_parse_cpio_cmdline ( image, &cpio,
401 ( cmdline + 1 /* ' ' */ ));
402 }
403 offset = ( ( sizeof ( cpio ) + name_len + 0x03 ) & ~0x03 );
404 } else {
405 offset = 0;
406 name_len = 0;
407 }
408
409 /* Copy in initrd image body (and cpio header if applicable) */
410 if ( address ) {
411 memmove_user ( address, offset, initrd->data, 0, initrd->len );
412 if ( offset ) {
413 memset_user ( address, 0, 0, offset );
414 copy_to_user ( address, 0, &cpio, sizeof ( cpio ) );
415 copy_to_user ( address, sizeof ( cpio ), filename,
416 ( name_len - 1 /* NUL (or space) */ ) );
417 }
418 DBGC ( image, "bzImage %p initrd %p [%#08lx,%#08lx,%#08lx)"
419 "%s%s\n", image, initrd, user_to_phys ( address, 0 ),
420 user_to_phys ( address, offset ),
421 user_to_phys ( address, ( offset + initrd->len ) ),
422 ( filename ? " " : "" ), ( filename ? filename : "" ) );
423 DBGC2_MD5A ( image, user_to_phys ( address, offset ),
424 user_to_virt ( address, offset ), initrd->len );
425 }
426 offset += initrd->len;
427
428 /* Zero-pad to next INITRD_ALIGN boundary */
429 pad_len = ( ( -offset ) & ( INITRD_ALIGN - 1 ) );
430 if ( address )
431 memset_user ( address, offset, 0, pad_len );
432
433 return offset;
434 }
435
436 /**
437 * Check that initrds can be loaded
438 *
439 * @v image bzImage image
440 * @v bzimg bzImage context
441 * @ret rc Return status code
442 */
bzimage_check_initrds(struct image * image,struct bzimage_context * bzimg)443 static int bzimage_check_initrds ( struct image *image,
444 struct bzimage_context *bzimg ) {
445 struct image *initrd;
446 userptr_t bottom;
447 size_t len = 0;
448 int rc;
449
450 /* Calculate total loaded length of initrds */
451 for_each_image ( initrd ) {
452
453 /* Skip kernel */
454 if ( initrd == image )
455 continue;
456
457 /* Calculate length */
458 len += bzimage_load_initrd ( image, initrd, UNULL );
459 len = bzimage_align ( len );
460
461 DBGC ( image, "bzImage %p initrd %p from [%#08lx,%#08lx)%s%s\n",
462 image, initrd, user_to_phys ( initrd->data, 0 ),
463 user_to_phys ( initrd->data, initrd->len ),
464 ( initrd->cmdline ? " " : "" ),
465 ( initrd->cmdline ? initrd->cmdline : "" ) );
466 DBGC2_MD5A ( image, user_to_phys ( initrd->data, 0 ),
467 user_to_virt ( initrd->data, 0 ), initrd->len );
468 }
469
470 /* Calculate lowest usable address */
471 bottom = userptr_add ( bzimg->pm_kernel, bzimg->pm_sz );
472
473 /* Check that total length fits within space available for
474 * reshuffling. This is a conservative check, since CPIO
475 * headers are not present during reshuffling, but this
476 * doesn't hurt and keeps the code simple.
477 */
478 if ( ( rc = initrd_reshuffle_check ( len, bottom ) ) != 0 ) {
479 DBGC ( image, "bzImage %p failed reshuffle check: %s\n",
480 image, strerror ( rc ) );
481 return rc;
482 }
483
484 /* Check that total length fits within kernel's memory limit */
485 if ( user_to_phys ( bottom, len ) > bzimg->mem_limit ) {
486 DBGC ( image, "bzImage %p not enough space for initrds\n",
487 image );
488 return -ENOBUFS;
489 }
490
491 return 0;
492 }
493
494 /**
495 * Load initrds, if any
496 *
497 * @v image bzImage image
498 * @v bzimg bzImage context
499 */
bzimage_load_initrds(struct image * image,struct bzimage_context * bzimg)500 static void bzimage_load_initrds ( struct image *image,
501 struct bzimage_context *bzimg ) {
502 struct image *initrd;
503 struct image *highest = NULL;
504 struct image *other;
505 userptr_t top;
506 userptr_t dest;
507 size_t offset;
508 size_t len;
509
510 /* Reshuffle initrds into desired order */
511 initrd_reshuffle ( userptr_add ( bzimg->pm_kernel, bzimg->pm_sz ) );
512
513 /* Find highest initrd */
514 for_each_image ( initrd ) {
515 if ( ( highest == NULL ) ||
516 ( userptr_sub ( initrd->data, highest->data ) > 0 ) ) {
517 highest = initrd;
518 }
519 }
520
521 /* Do nothing if there are no initrds */
522 if ( ! highest )
523 return;
524
525 /* Find highest usable address */
526 top = userptr_add ( highest->data, bzimage_align ( highest->len ) );
527 if ( user_to_phys ( top, -1 ) > bzimg->mem_limit ) {
528 top = phys_to_user ( ( bzimg->mem_limit + 1 ) &
529 ~( INITRD_ALIGN - 1 ) );
530 }
531 DBGC ( image, "bzImage %p loading initrds from %#08lx downwards\n",
532 image, user_to_phys ( top, -1 ) );
533
534 /* Load initrds in order */
535 for_each_image ( initrd ) {
536
537 /* Calculate cumulative length of following
538 * initrds (including padding).
539 */
540 offset = 0;
541 for_each_image ( other ) {
542 if ( other == initrd )
543 offset = 0;
544 offset += bzimage_load_initrd ( image, other, UNULL );
545 offset = bzimage_align ( offset );
546 }
547
548 /* Load initrd at this address */
549 dest = userptr_add ( top, -offset );
550 len = bzimage_load_initrd ( image, initrd, dest );
551
552 /* Record initrd location */
553 if ( ! bzimg->ramdisk_image )
554 bzimg->ramdisk_image = user_to_phys ( dest, 0 );
555 bzimg->ramdisk_size = ( user_to_phys ( dest, len ) -
556 bzimg->ramdisk_image );
557 }
558 DBGC ( image, "bzImage %p initrds at [%#08lx,%#08lx)\n",
559 image, bzimg->ramdisk_image,
560 ( bzimg->ramdisk_image + bzimg->ramdisk_size ) );
561 }
562
563 /**
564 * Execute bzImage image
565 *
566 * @v image bzImage image
567 * @ret rc Return status code
568 */
bzimage_exec(struct image * image)569 static int bzimage_exec ( struct image *image ) {
570 struct bzimage_context bzimg;
571 const char *cmdline = ( image->cmdline ? image->cmdline : "" );
572 int rc;
573
574 /* Read and parse header from image */
575 if ( ( rc = bzimage_parse_header ( image, &bzimg,
576 image->data ) ) != 0 )
577 return rc;
578
579 /* Prepare segments */
580 if ( ( rc = prep_segment ( bzimg.rm_kernel, bzimg.rm_filesz,
581 bzimg.rm_memsz ) ) != 0 ) {
582 DBGC ( image, "bzImage %p could not prepare RM segment: %s\n",
583 image, strerror ( rc ) );
584 return rc;
585 }
586 if ( ( rc = prep_segment ( bzimg.pm_kernel, bzimg.pm_sz,
587 bzimg.pm_sz ) ) != 0 ) {
588 DBGC ( image, "bzImage %p could not prepare PM segment: %s\n",
589 image, strerror ( rc ) );
590 return rc;
591 }
592
593 /* Parse command line for bootloader parameters */
594 if ( ( rc = bzimage_parse_cmdline ( image, &bzimg, cmdline ) ) != 0)
595 return rc;
596
597 /* Check that initrds can be loaded */
598 if ( ( rc = bzimage_check_initrds ( image, &bzimg ) ) != 0 )
599 return rc;
600
601 /* Remove kernel from image list (without invalidating image pointer) */
602 unregister_image ( image_get ( image ) );
603
604 /* Load segments */
605 memcpy_user ( bzimg.rm_kernel, 0, image->data,
606 0, bzimg.rm_filesz );
607 memcpy_user ( bzimg.pm_kernel, 0, image->data,
608 bzimg.rm_filesz, bzimg.pm_sz );
609
610 /* Store command line */
611 bzimage_set_cmdline ( image, &bzimg, cmdline );
612
613 /* Prepare for exiting. Must do this before loading initrds,
614 * since loading the initrds will corrupt the external heap.
615 */
616 shutdown_boot();
617
618 /* Load any initrds */
619 bzimage_load_initrds ( image, &bzimg );
620
621 /* Update kernel header */
622 bzimage_update_header ( image, &bzimg, bzimg.rm_kernel );
623
624 DBGC ( image, "bzImage %p jumping to RM kernel at %04x:0000 "
625 "(stack %04x:%04zx)\n", image, ( bzimg.rm_kernel_seg + 0x20 ),
626 bzimg.rm_kernel_seg, bzimg.rm_heap );
627
628 /* Jump to the kernel */
629 __asm__ __volatile__ ( REAL_CODE ( "movw %w0, %%ds\n\t"
630 "movw %w0, %%es\n\t"
631 "movw %w0, %%fs\n\t"
632 "movw %w0, %%gs\n\t"
633 "movw %w0, %%ss\n\t"
634 "movw %w1, %%sp\n\t"
635 "pushw %w2\n\t"
636 "pushw $0\n\t"
637 "lret\n\t" )
638 : : "R" ( bzimg.rm_kernel_seg ),
639 "R" ( bzimg.rm_heap ),
640 "R" ( bzimg.rm_kernel_seg + 0x20 ) );
641
642 /* There is no way for the image to return, since we provide
643 * no return address.
644 */
645 assert ( 0 );
646
647 return -ECANCELED; /* -EIMPOSSIBLE */
648 }
649
650 /**
651 * Probe bzImage image
652 *
653 * @v image bzImage file
654 * @ret rc Return status code
655 */
bzimage_probe(struct image * image)656 int bzimage_probe ( struct image *image ) {
657 struct bzimage_context bzimg;
658 int rc;
659
660 /* Read and parse header from image */
661 if ( ( rc = bzimage_parse_header ( image, &bzimg,
662 image->data ) ) != 0 )
663 return rc;
664
665 return 0;
666 }
667
668 /** Linux bzImage image type */
669 struct image_type bzimage_image_type __image_type ( PROBE_NORMAL ) = {
670 .name = "bzImage",
671 .probe = bzimage_probe,
672 .exec = bzimage_exec,
673 };
674