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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/efi.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/i386/kernel/efi.c')
-rw-r--r--arch/i386/kernel/efi.c635
1 files changed, 635 insertions, 0 deletions
diff --git a/arch/i386/kernel/efi.c b/arch/i386/kernel/efi.c
new file mode 100644
index 000000000000..9e5e0d8bd36e
--- /dev/null
+++ b/arch/i386/kernel/efi.c
@@ -0,0 +1,635 @@
1/*
2 * Extensible Firmware Interface
3 *
4 * Based on Extensible Firmware Interface Specification version 1.0
5 *
6 * Copyright (C) 1999 VA Linux Systems
7 * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
8 * Copyright (C) 1999-2002 Hewlett-Packard Co.
9 * David Mosberger-Tang <davidm@hpl.hp.com>
10 * Stephane Eranian <eranian@hpl.hp.com>
11 *
12 * All EFI Runtime Services are not implemented yet as EFI only
13 * supports physical mode addressing on SoftSDV. This is to be fixed
14 * in a future version. --drummond 1999-07-20
15 *
16 * Implemented EFI runtime services and virtual mode calls. --davidm
17 *
18 * Goutham Rao: <goutham.rao@intel.com>
19 * Skip non-WB memory and ignore empty memory ranges.
20 */
21
22#include <linux/config.h>
23#include <linux/kernel.h>
24#include <linux/init.h>
25#include <linux/mm.h>
26#include <linux/types.h>
27#include <linux/time.h>
28#include <linux/spinlock.h>
29#include <linux/bootmem.h>
30#include <linux/ioport.h>
31#include <linux/module.h>
32#include <linux/efi.h>
33
34#include <asm/setup.h>
35#include <asm/io.h>
36#include <asm/page.h>
37#include <asm/pgtable.h>
38#include <asm/processor.h>
39#include <asm/desc.h>
40#include <asm/tlbflush.h>
41
42#define EFI_DEBUG 0
43#define PFX "EFI: "
44
45extern efi_status_t asmlinkage efi_call_phys(void *, ...);
46
47struct efi efi;
48EXPORT_SYMBOL(efi);
49static struct efi efi_phys __initdata;
50struct efi_memory_map memmap __initdata;
51
52/*
53 * We require an early boot_ioremap mapping mechanism initially
54 */
55extern void * boot_ioremap(unsigned long, unsigned long);
56
57/*
58 * To make EFI call EFI runtime service in physical addressing mode we need
59 * prelog/epilog before/after the invocation to disable interrupt, to
60 * claim EFI runtime service handler exclusively and to duplicate a memory in
61 * low memory space say 0 - 3G.
62 */
63
64static unsigned long efi_rt_eflags;
65static DEFINE_SPINLOCK(efi_rt_lock);
66static pgd_t efi_bak_pg_dir_pointer[2];
67
68static void efi_call_phys_prelog(void)
69{
70 unsigned long cr4;
71 unsigned long temp;
72
73 spin_lock(&efi_rt_lock);
74 local_irq_save(efi_rt_eflags);
75
76 /*
77 * If I don't have PSE, I should just duplicate two entries in page
78 * directory. If I have PSE, I just need to duplicate one entry in
79 * page directory.
80 */
81 __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
82
83 if (cr4 & X86_CR4_PSE) {
84 efi_bak_pg_dir_pointer[0].pgd =
85 swapper_pg_dir[pgd_index(0)].pgd;
86 swapper_pg_dir[0].pgd =
87 swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
88 } else {
89 efi_bak_pg_dir_pointer[0].pgd =
90 swapper_pg_dir[pgd_index(0)].pgd;
91 efi_bak_pg_dir_pointer[1].pgd =
92 swapper_pg_dir[pgd_index(0x400000)].pgd;
93 swapper_pg_dir[pgd_index(0)].pgd =
94 swapper_pg_dir[pgd_index(PAGE_OFFSET)].pgd;
95 temp = PAGE_OFFSET + 0x400000;
96 swapper_pg_dir[pgd_index(0x400000)].pgd =
97 swapper_pg_dir[pgd_index(temp)].pgd;
98 }
99
100 /*
101 * After the lock is released, the original page table is restored.
102 */
103 local_flush_tlb();
104
105 cpu_gdt_descr[0].address = __pa(cpu_gdt_descr[0].address);
106 __asm__ __volatile__("lgdt %0":"=m"
107 (*(struct Xgt_desc_struct *) __pa(&cpu_gdt_descr[0])));
108}
109
110static void efi_call_phys_epilog(void)
111{
112 unsigned long cr4;
113
114 cpu_gdt_descr[0].address =
115 (unsigned long) __va(cpu_gdt_descr[0].address);
116 __asm__ __volatile__("lgdt %0":"=m"(cpu_gdt_descr));
117 __asm__ __volatile__("movl %%cr4, %0":"=r"(cr4));
118
119 if (cr4 & X86_CR4_PSE) {
120 swapper_pg_dir[pgd_index(0)].pgd =
121 efi_bak_pg_dir_pointer[0].pgd;
122 } else {
123 swapper_pg_dir[pgd_index(0)].pgd =
124 efi_bak_pg_dir_pointer[0].pgd;
125 swapper_pg_dir[pgd_index(0x400000)].pgd =
126 efi_bak_pg_dir_pointer[1].pgd;
127 }
128
129 /*
130 * After the lock is released, the original page table is restored.
131 */
132 local_flush_tlb();
133
134 local_irq_restore(efi_rt_eflags);
135 spin_unlock(&efi_rt_lock);
136}
137
138static efi_status_t
139phys_efi_set_virtual_address_map(unsigned long memory_map_size,
140 unsigned long descriptor_size,
141 u32 descriptor_version,
142 efi_memory_desc_t *virtual_map)
143{
144 efi_status_t status;
145
146 efi_call_phys_prelog();
147 status = efi_call_phys(efi_phys.set_virtual_address_map,
148 memory_map_size, descriptor_size,
149 descriptor_version, virtual_map);
150 efi_call_phys_epilog();
151 return status;
152}
153
154static efi_status_t
155phys_efi_get_time(efi_time_t *tm, efi_time_cap_t *tc)
156{
157 efi_status_t status;
158
159 efi_call_phys_prelog();
160 status = efi_call_phys(efi_phys.get_time, tm, tc);
161 efi_call_phys_epilog();
162 return status;
163}
164
165inline int efi_set_rtc_mmss(unsigned long nowtime)
166{
167 int real_seconds, real_minutes;
168 efi_status_t status;
169 efi_time_t eft;
170 efi_time_cap_t cap;
171
172 spin_lock(&efi_rt_lock);
173 status = efi.get_time(&eft, &cap);
174 spin_unlock(&efi_rt_lock);
175 if (status != EFI_SUCCESS)
176 panic("Ooops, efitime: can't read time!\n");
177 real_seconds = nowtime % 60;
178 real_minutes = nowtime / 60;
179
180 if (((abs(real_minutes - eft.minute) + 15)/30) & 1)
181 real_minutes += 30;
182 real_minutes %= 60;
183
184 eft.minute = real_minutes;
185 eft.second = real_seconds;
186
187 if (status != EFI_SUCCESS) {
188 printk("Ooops: efitime: can't read time!\n");
189 return -1;
190 }
191 return 0;
192}
193/*
194 * This should only be used during kernel init and before runtime
195 * services have been remapped, therefore, we'll need to call in physical
196 * mode. Note, this call isn't used later, so mark it __init.
197 */
198inline unsigned long __init efi_get_time(void)
199{
200 efi_status_t status;
201 efi_time_t eft;
202 efi_time_cap_t cap;
203
204 status = phys_efi_get_time(&eft, &cap);
205 if (status != EFI_SUCCESS)
206 printk("Oops: efitime: can't read time status: 0x%lx\n",status);
207
208 return mktime(eft.year, eft.month, eft.day, eft.hour,
209 eft.minute, eft.second);
210}
211
212int is_available_memory(efi_memory_desc_t * md)
213{
214 if (!(md->attribute & EFI_MEMORY_WB))
215 return 0;
216
217 switch (md->type) {
218 case EFI_LOADER_CODE:
219 case EFI_LOADER_DATA:
220 case EFI_BOOT_SERVICES_CODE:
221 case EFI_BOOT_SERVICES_DATA:
222 case EFI_CONVENTIONAL_MEMORY:
223 return 1;
224 }
225 return 0;
226}
227
228/*
229 * We need to map the EFI memory map again after paging_init().
230 */
231void __init efi_map_memmap(void)
232{
233 memmap.map = NULL;
234
235 memmap.map = (efi_memory_desc_t *)
236 bt_ioremap((unsigned long) memmap.phys_map,
237 (memmap.nr_map * sizeof(efi_memory_desc_t)));
238
239 if (memmap.map == NULL)
240 printk(KERN_ERR PFX "Could not remap the EFI memmap!\n");
241}
242
243#if EFI_DEBUG
244static void __init print_efi_memmap(void)
245{
246 efi_memory_desc_t *md;
247 int i;
248
249 for (i = 0; i < memmap.nr_map; i++) {
250 md = &memmap.map[i];
251 printk(KERN_INFO "mem%02u: type=%u, attr=0x%llx, "
252 "range=[0x%016llx-0x%016llx) (%lluMB)\n",
253 i, md->type, md->attribute, md->phys_addr,
254 md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT),
255 (md->num_pages >> (20 - EFI_PAGE_SHIFT)));
256 }
257}
258#endif /* EFI_DEBUG */
259
260/*
261 * Walks the EFI memory map and calls CALLBACK once for each EFI
262 * memory descriptor that has memory that is available for kernel use.
263 */
264void efi_memmap_walk(efi_freemem_callback_t callback, void *arg)
265{
266 int prev_valid = 0;
267 struct range {
268 unsigned long start;
269 unsigned long end;
270 } prev, curr;
271 efi_memory_desc_t *md;
272 unsigned long start, end;
273 int i;
274
275 for (i = 0; i < memmap.nr_map; i++) {
276 md = &memmap.map[i];
277
278 if ((md->num_pages == 0) || (!is_available_memory(md)))
279 continue;
280
281 curr.start = md->phys_addr;
282 curr.end = curr.start + (md->num_pages << EFI_PAGE_SHIFT);
283
284 if (!prev_valid) {
285 prev = curr;
286 prev_valid = 1;
287 } else {
288 if (curr.start < prev.start)
289 printk(KERN_INFO PFX "Unordered memory map\n");
290 if (prev.end == curr.start)
291 prev.end = curr.end;
292 else {
293 start =
294 (unsigned long) (PAGE_ALIGN(prev.start));
295 end = (unsigned long) (prev.end & PAGE_MASK);
296 if ((end > start)
297 && (*callback) (start, end, arg) < 0)
298 return;
299 prev = curr;
300 }
301 }
302 }
303 if (prev_valid) {
304 start = (unsigned long) PAGE_ALIGN(prev.start);
305 end = (unsigned long) (prev.end & PAGE_MASK);
306 if (end > start)
307 (*callback) (start, end, arg);
308 }
309}
310
311void __init efi_init(void)
312{
313 efi_config_table_t *config_tables;
314 efi_runtime_services_t *runtime;
315 efi_char16_t *c16;
316 char vendor[100] = "unknown";
317 unsigned long num_config_tables;
318 int i = 0;
319
320 memset(&efi, 0, sizeof(efi) );
321 memset(&efi_phys, 0, sizeof(efi_phys));
322
323 efi_phys.systab = EFI_SYSTAB;
324 memmap.phys_map = EFI_MEMMAP;
325 memmap.nr_map = EFI_MEMMAP_SIZE/EFI_MEMDESC_SIZE;
326 memmap.desc_version = EFI_MEMDESC_VERSION;
327
328 efi.systab = (efi_system_table_t *)
329 boot_ioremap((unsigned long) efi_phys.systab,
330 sizeof(efi_system_table_t));
331 /*
332 * Verify the EFI Table
333 */
334 if (efi.systab == NULL)
335 printk(KERN_ERR PFX "Woah! Couldn't map the EFI system table.\n");
336 if (efi.systab->hdr.signature != EFI_SYSTEM_TABLE_SIGNATURE)
337 printk(KERN_ERR PFX "Woah! EFI system table signature incorrect\n");
338 if ((efi.systab->hdr.revision ^ EFI_SYSTEM_TABLE_REVISION) >> 16 != 0)
339 printk(KERN_ERR PFX
340 "Warning: EFI system table major version mismatch: "
341 "got %d.%02d, expected %d.%02d\n",
342 efi.systab->hdr.revision >> 16,
343 efi.systab->hdr.revision & 0xffff,
344 EFI_SYSTEM_TABLE_REVISION >> 16,
345 EFI_SYSTEM_TABLE_REVISION & 0xffff);
346 /*
347 * Grab some details from the system table
348 */
349 num_config_tables = efi.systab->nr_tables;
350 config_tables = (efi_config_table_t *)efi.systab->tables;
351 runtime = efi.systab->runtime;
352
353 /*
354 * Show what we know for posterity
355 */
356 c16 = (efi_char16_t *) boot_ioremap(efi.systab->fw_vendor, 2);
357 if (c16) {
358 for (i = 0; i < sizeof(vendor) && *c16; ++i)
359 vendor[i] = *c16++;
360 vendor[i] = '\0';
361 } else
362 printk(KERN_ERR PFX "Could not map the firmware vendor!\n");
363
364 printk(KERN_INFO PFX "EFI v%u.%.02u by %s \n",
365 efi.systab->hdr.revision >> 16,
366 efi.systab->hdr.revision & 0xffff, vendor);
367
368 /*
369 * Let's see what config tables the firmware passed to us.
370 */
371 config_tables = (efi_config_table_t *)
372 boot_ioremap((unsigned long) config_tables,
373 num_config_tables * sizeof(efi_config_table_t));
374
375 if (config_tables == NULL)
376 printk(KERN_ERR PFX "Could not map EFI Configuration Table!\n");
377
378 for (i = 0; i < num_config_tables; i++) {
379 if (efi_guidcmp(config_tables[i].guid, MPS_TABLE_GUID) == 0) {
380 efi.mps = (void *)config_tables[i].table;
381 printk(KERN_INFO " MPS=0x%lx ", config_tables[i].table);
382 } else
383 if (efi_guidcmp(config_tables[i].guid, ACPI_20_TABLE_GUID) == 0) {
384 efi.acpi20 = __va(config_tables[i].table);
385 printk(KERN_INFO " ACPI 2.0=0x%lx ", config_tables[i].table);
386 } else
387 if (efi_guidcmp(config_tables[i].guid, ACPI_TABLE_GUID) == 0) {
388 efi.acpi = __va(config_tables[i].table);
389 printk(KERN_INFO " ACPI=0x%lx ", config_tables[i].table);
390 } else
391 if (efi_guidcmp(config_tables[i].guid, SMBIOS_TABLE_GUID) == 0) {
392 efi.smbios = (void *) config_tables[i].table;
393 printk(KERN_INFO " SMBIOS=0x%lx ", config_tables[i].table);
394 } else
395 if (efi_guidcmp(config_tables[i].guid, HCDP_TABLE_GUID) == 0) {
396 efi.hcdp = (void *)config_tables[i].table;
397 printk(KERN_INFO " HCDP=0x%lx ", config_tables[i].table);
398 } else
399 if (efi_guidcmp(config_tables[i].guid, UGA_IO_PROTOCOL_GUID) == 0) {
400 efi.uga = (void *)config_tables[i].table;
401 printk(KERN_INFO " UGA=0x%lx ", config_tables[i].table);
402 }
403 }
404 printk("\n");
405
406 /*
407 * Check out the runtime services table. We need to map
408 * the runtime services table so that we can grab the physical
409 * address of several of the EFI runtime functions, needed to
410 * set the firmware into virtual mode.
411 */
412
413 runtime = (efi_runtime_services_t *) boot_ioremap((unsigned long)
414 runtime,
415 sizeof(efi_runtime_services_t));
416 if (runtime != NULL) {
417 /*
418 * We will only need *early* access to the following
419 * two EFI runtime services before set_virtual_address_map
420 * is invoked.
421 */
422 efi_phys.get_time = (efi_get_time_t *) runtime->get_time;
423 efi_phys.set_virtual_address_map =
424 (efi_set_virtual_address_map_t *)
425 runtime->set_virtual_address_map;
426 } else
427 printk(KERN_ERR PFX "Could not map the runtime service table!\n");
428
429 /* Map the EFI memory map for use until paging_init() */
430
431 memmap.map = (efi_memory_desc_t *)
432 boot_ioremap((unsigned long) EFI_MEMMAP, EFI_MEMMAP_SIZE);
433
434 if (memmap.map == NULL)
435 printk(KERN_ERR PFX "Could not map the EFI memory map!\n");
436
437 if (EFI_MEMDESC_SIZE != sizeof(efi_memory_desc_t)) {
438 printk(KERN_WARNING PFX "Warning! Kernel-defined memdesc doesn't "
439 "match the one from EFI!\n");
440 }
441#if EFI_DEBUG
442 print_efi_memmap();
443#endif
444}
445
446/*
447 * This function will switch the EFI runtime services to virtual mode.
448 * Essentially, look through the EFI memmap and map every region that
449 * has the runtime attribute bit set in its memory descriptor and update
450 * that memory descriptor with the virtual address obtained from ioremap().
451 * This enables the runtime services to be called without having to
452 * thunk back into physical mode for every invocation.
453 */
454
455void __init efi_enter_virtual_mode(void)
456{
457 efi_memory_desc_t *md;
458 efi_status_t status;
459 int i;
460
461 efi.systab = NULL;
462
463 for (i = 0; i < memmap.nr_map; i++) {
464 md = &memmap.map[i];
465
466 if (md->attribute & EFI_MEMORY_RUNTIME) {
467 md->virt_addr =
468 (unsigned long)ioremap(md->phys_addr,
469 md->num_pages << EFI_PAGE_SHIFT);
470 if (!(unsigned long)md->virt_addr) {
471 printk(KERN_ERR PFX "ioremap of 0x%lX failed\n",
472 (unsigned long)md->phys_addr);
473 }
474
475 if (((unsigned long)md->phys_addr <=
476 (unsigned long)efi_phys.systab) &&
477 ((unsigned long)efi_phys.systab <
478 md->phys_addr +
479 ((unsigned long)md->num_pages <<
480 EFI_PAGE_SHIFT))) {
481 unsigned long addr;
482
483 addr = md->virt_addr - md->phys_addr +
484 (unsigned long)efi_phys.systab;
485 efi.systab = (efi_system_table_t *)addr;
486 }
487 }
488 }
489
490 if (!efi.systab)
491 BUG();
492
493 status = phys_efi_set_virtual_address_map(
494 sizeof(efi_memory_desc_t) * memmap.nr_map,
495 sizeof(efi_memory_desc_t),
496 memmap.desc_version,
497 memmap.phys_map);
498
499 if (status != EFI_SUCCESS) {
500 printk (KERN_ALERT "You are screwed! "
501 "Unable to switch EFI into virtual mode "
502 "(status=%lx)\n", status);
503 panic("EFI call to SetVirtualAddressMap() failed!");
504 }
505
506 /*
507 * Now that EFI is in virtual mode, update the function
508 * pointers in the runtime service table to the new virtual addresses.
509 */
510
511 efi.get_time = (efi_get_time_t *) efi.systab->runtime->get_time;
512 efi.set_time = (efi_set_time_t *) efi.systab->runtime->set_time;
513 efi.get_wakeup_time = (efi_get_wakeup_time_t *)
514 efi.systab->runtime->get_wakeup_time;
515 efi.set_wakeup_time = (efi_set_wakeup_time_t *)
516 efi.systab->runtime->set_wakeup_time;
517 efi.get_variable = (efi_get_variable_t *)
518 efi.systab->runtime->get_variable;
519 efi.get_next_variable = (efi_get_next_variable_t *)
520 efi.systab->runtime->get_next_variable;
521 efi.set_variable = (efi_set_variable_t *)
522 efi.systab->runtime->set_variable;
523 efi.get_next_high_mono_count = (efi_get_next_high_mono_count_t *)
524 efi.systab->runtime->get_next_high_mono_count;
525 efi.reset_system = (efi_reset_system_t *)
526 efi.systab->runtime->reset_system;
527}
528
529void __init
530efi_initialize_iomem_resources(struct resource *code_resource,
531 struct resource *data_resource)
532{
533 struct resource *res;
534 efi_memory_desc_t *md;
535 int i;
536
537 for (i = 0; i < memmap.nr_map; i++) {
538 md = &memmap.map[i];
539
540 if ((md->phys_addr + (md->num_pages << EFI_PAGE_SHIFT)) >
541 0x100000000ULL)
542 continue;
543 res = alloc_bootmem_low(sizeof(struct resource));
544 switch (md->type) {
545 case EFI_RESERVED_TYPE:
546 res->name = "Reserved Memory";
547 break;
548 case EFI_LOADER_CODE:
549 res->name = "Loader Code";
550 break;
551 case EFI_LOADER_DATA:
552 res->name = "Loader Data";
553 break;
554 case EFI_BOOT_SERVICES_DATA:
555 res->name = "BootServices Data";
556 break;
557 case EFI_BOOT_SERVICES_CODE:
558 res->name = "BootServices Code";
559 break;
560 case EFI_RUNTIME_SERVICES_CODE:
561 res->name = "Runtime Service Code";
562 break;
563 case EFI_RUNTIME_SERVICES_DATA:
564 res->name = "Runtime Service Data";
565 break;
566 case EFI_CONVENTIONAL_MEMORY:
567 res->name = "Conventional Memory";
568 break;
569 case EFI_UNUSABLE_MEMORY:
570 res->name = "Unusable Memory";
571 break;
572 case EFI_ACPI_RECLAIM_MEMORY:
573 res->name = "ACPI Reclaim";
574 break;
575 case EFI_ACPI_MEMORY_NVS:
576 res->name = "ACPI NVS";
577 break;
578 case EFI_MEMORY_MAPPED_IO:
579 res->name = "Memory Mapped IO";
580 break;
581 case EFI_MEMORY_MAPPED_IO_PORT_SPACE:
582 res->name = "Memory Mapped IO Port Space";
583 break;
584 default:
585 res->name = "Reserved";
586 break;
587 }
588 res->start = md->phys_addr;
589 res->end = res->start + ((md->num_pages << EFI_PAGE_SHIFT) - 1);
590 res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
591 if (request_resource(&iomem_resource, res) < 0)
592 printk(KERN_ERR PFX "Failed to allocate res %s : 0x%lx-0x%lx\n",
593 res->name, res->start, res->end);
594 /*
595 * We don't know which region contains kernel data so we try
596 * it repeatedly and let the resource manager test it.
597 */
598 if (md->type == EFI_CONVENTIONAL_MEMORY) {
599 request_resource(res, code_resource);
600 request_resource(res, data_resource);
601 }
602 }
603}
604
605/*
606 * Convenience functions to obtain memory types and attributes
607 */
608
609u32 efi_mem_type(unsigned long phys_addr)
610{
611 efi_memory_desc_t *md;
612 int i;
613
614 for (i = 0; i < memmap.nr_map; i++) {
615 md = &memmap.map[i];
616 if ((md->phys_addr <= phys_addr) && (phys_addr <
617 (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
618 return md->type;
619 }
620 return 0;
621}
622
623u64 efi_mem_attributes(unsigned long phys_addr)
624{
625 efi_memory_desc_t *md;
626 int i;
627
628 for (i = 0; i < memmap.nr_map; i++) {
629 md = &memmap.map[i];
630 if ((md->phys_addr <= phys_addr) && (phys_addr <
631 (md->phys_addr + (md-> num_pages << EFI_PAGE_SHIFT)) ))
632 return md->attribute;
633 }
634 return 0;
635}