module.c

优龙2410linux2.6.8内核源代码

 * 	ldo 0(%r1), %r1
 * 	ldd 10(%r1), %r1
 * 	bve,n (%r1)
 */
	if (!millicode)
	{
		stub->insns[0] = 0x537b0000;	/* ldd 0(%dp),%dp	*/
		stub->insns[1] = 0x53610020;	/* ldd 10(%dp),%r1	*/
		stub->insns[2] = 0xe820d000;	/* bve (%r1)		*/
		stub->insns[3] = 0x537b0030;	/* ldd 18(%dp),%dp	*/

		stub->insns[0] |= reassemble_14(get_got(me, value, addend) & 0x3fff);
	}
	else
	{
		stub->insns[0] = 0x20200000;	/* ldil 0,%r1		*/
		stub->insns[1] = 0x34210000;	/* ldo 0(%r1), %r1	*/
		stub->insns[2] = 0x50210020;	/* ldd 10(%r1),%r1	*/
		stub->insns[3] = 0xe820d002;	/* bve,n (%r1)		*/

		stub->insns[0] |= reassemble_21(lrsel(value, addend));
		stub->insns[1] |= reassemble_14(rrsel(value, addend));
	}
#endif

	return (Elf_Addr)stub;
}

int apply_relocate(Elf_Shdr *sechdrs,
		   const char *strtab,
		   unsigned int symindex,
		   unsigned int relsec,
		   struct module *me)
{
	/* parisc should not need this ... */
	printk(KERN_ERR "module %s: RELOCATION unsupported\n",
	       me->name);
	return -ENOEXEC;
}

#ifndef __LP64__
int apply_relocate_add(Elf_Shdr *sechdrs,
		       const char *strtab,
		       unsigned int symindex,
		       unsigned int relsec,
		       struct module *me)
{
	int i;
	Elf32_Rela *rel = (void *)sechdrs[relsec].sh_addr;
	Elf32_Sym *sym;
	Elf32_Word *loc;
	Elf32_Addr val;
	Elf32_Sword addend;
	Elf32_Addr dot;
	//unsigned long dp = (unsigned long)$global$;
	register unsigned long dp asm ("r27");

	DEBUGP("Applying relocate section %u to %u\n", relsec,
	       sechdrs[relsec].sh_info);
	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
		/* This is where to make the change */
		loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
		      + rel[i].r_offset;
		/* This is the symbol it is referring to */
		sym = (Elf32_Sym *)sechdrs[symindex].sh_addr
			+ ELF32_R_SYM(rel[i].r_info);
		if (!sym->st_value) {
			printk(KERN_WARNING "%s: Unknown symbol %s\n",
			       me->name, strtab + sym->st_name);
			return -ENOENT;
		}
		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
		dot =  (Elf32_Addr)loc & ~0x03;

		val = sym->st_value;
		addend = rel[i].r_addend;

#if 0
#define r(t) ELF32_R_TYPE(rel[i].r_info)==t ? #t :
		DEBUGP("Symbol %s loc 0x%x val 0x%x addend 0x%x: %s\n",
			strtab + sym->st_name,
			(uint32_t)loc, val, addend,
			r(R_PARISC_PLABEL32)
			r(R_PARISC_DIR32)
			r(R_PARISC_DIR21L)
			r(R_PARISC_DIR14R)
			r(R_PARISC_SEGREL32)
			r(R_PARISC_DPREL21L)
			r(R_PARISC_DPREL14R)
			r(R_PARISC_PCREL17F)
			r(R_PARISC_PCREL22F)
			"UNKNOWN");
#undef r
#endif

		switch (ELF32_R_TYPE(rel[i].r_info)) {
		case R_PARISC_PLABEL32:
			/* 32-bit function address */
			/* no function descriptors... */
			*loc = fsel(val, addend);
			break;
		case R_PARISC_DIR32:
			/* direct 32-bit ref */
			*loc = fsel(val, addend);
			break;
		case R_PARISC_DIR21L:
			/* left 21 bits of effective address */
			val = lrsel(val, addend);
			*loc = mask(*loc, 21) | reassemble_21(val);
			break;
		case R_PARISC_DIR14R:
			/* right 14 bits of effective address */
			val = rrsel(val, addend);
			*loc = mask(*loc, 14) | reassemble_14(val);
			break;
		case R_PARISC_SEGREL32:
			/* 32-bit segment relative address */
			val -= (uint32_t)me->module_core;
			*loc = fsel(val, addend); 
			break;
		case R_PARISC_DPREL21L:
			/* left 21 bit of relative address */
			val = lrsel(val - dp, addend);
			*loc = mask(*loc, 21) | reassemble_21(val);
			break;
		case R_PARISC_DPREL14R:
			/* right 14 bit of relative address */
			val = rrsel(val - dp, addend);
			*loc = mask(*loc, 14) | reassemble_14(val);
			break;
		case R_PARISC_PCREL17F:
			/* 17-bit PC relative address */
			val = get_stub(me, val, addend, 0, is_init(me, loc));
			val = (val - dot - 8)/4;
			CHECK_RELOC(val, 17)
			*loc = (*loc & ~0x1f1ffd) | reassemble_17(val);
			break;
		case R_PARISC_PCREL22F:
			/* 22-bit PC relative address; only defined for pa20 */
			val = get_stub(me, val, addend, 0, is_init(me, loc));
			DEBUGP("STUB FOR %s loc %lx+%lx at %lx\n", 
			       strtab + sym->st_name, (unsigned long)loc, addend, 
			       val)
			val = (val - dot - 8)/4;
			CHECK_RELOC(val, 22);
			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
			break;

		default:
			printk(KERN_ERR "module %s: Unknown relocation: %u\n",
			       me->name, ELF32_R_TYPE(rel[i].r_info));
			return -ENOEXEC;
		}
	}

	return 0;
}

#else
int apply_relocate_add(Elf_Shdr *sechdrs,
		       const char *strtab,
		       unsigned int symindex,
		       unsigned int relsec,
		       struct module *me)
{
	int i;
	Elf64_Rela *rel = (void *)sechdrs[relsec].sh_addr;
	Elf64_Sym *sym;
	Elf64_Word *loc;
	Elf64_Xword *loc64;
	Elf64_Addr val;
	Elf64_Sxword addend;
	Elf64_Addr dot;

	DEBUGP("Applying relocate section %u to %u\n", relsec,
	       sechdrs[relsec].sh_info);
	for (i = 0; i < sechdrs[relsec].sh_size / sizeof(*rel); i++) {
		/* This is where to make the change */
		loc = (void *)sechdrs[sechdrs[relsec].sh_info].sh_addr
		      + rel[i].r_offset;
		/* This is the symbol it is referring to */
		sym = (Elf64_Sym *)sechdrs[symindex].sh_addr
			+ ELF64_R_SYM(rel[i].r_info);
		if (!sym->st_value) {
			printk(KERN_WARNING "%s: Unknown symbol %s\n",
			       me->name, strtab + sym->st_name);
			return -ENOENT;
		}
		//dot = (sechdrs[relsec].sh_addr + rel->r_offset) & ~0x03;
		dot = (Elf64_Addr)loc & ~0x03;
		loc64 = (Elf64_Xword *)loc;

		val = sym->st_value;
		addend = rel[i].r_addend;

#if 0
#define r(t) ELF64_R_TYPE(rel[i].r_info)==t ? #t :
		printk("Symbol %s loc %p val 0x%Lx addend 0x%Lx: %s\n",
			strtab + sym->st_name,
			loc, val, addend,
			r(R_PARISC_LTOFF14R)
			r(R_PARISC_LTOFF21L)
			r(R_PARISC_PCREL22F)
			r(R_PARISC_DIR64)
			r(R_PARISC_SEGREL32)
			r(R_PARISC_FPTR64)
			"UNKNOWN");
#undef r
#endif

		switch (ELF64_R_TYPE(rel[i].r_info)) {
		case R_PARISC_LTOFF21L:
			/* LT-relative; left 21 bits */
			val = get_got(me, val, addend);
			DEBUGP("LTOFF21L Symbol %s loc %p val %lx\n",
			       strtab + sym->st_name,
			       loc, val);
			val = lrsel(val, 0);
			*loc = mask(*loc, 21) | reassemble_21(val);
			break;
		case R_PARISC_LTOFF14R:
			/* L(ltoff(val+addend)) */
			/* LT-relative; right 14 bits */
			val = get_got(me, val, addend);
			val = rrsel(val, 0);
			DEBUGP("LTOFF14R Symbol %s loc %p val %lx\n",
			       strtab + sym->st_name,
			       loc, val);
			*loc = mask(*loc, 14) | reassemble_14(val);
			break;
		case R_PARISC_PCREL22F:
			/* PC-relative; 22 bits */
			DEBUGP("PCREL22F Symbol %s loc %p val %lx\n",
			       strtab + sym->st_name,
			       loc, val);
			/* can we reach it locally? */
			if(!is_local(me, (void *)val)) {
				if (strncmp(strtab + sym->st_name, "$$", 2)
				    == 0)
					val = get_stub(me, val, addend, 1,
						       is_init(me, loc));
				else
					val = get_stub(me, val, addend, 0,
						       is_init(me, loc));
			}
			DEBUGP("STUB FOR %s loc %lx, val %lx+%lx at %lx\n", 
			       strtab + sym->st_name, loc, sym->st_value,
			       addend, val);
			/* FIXME: local symbols work as long as the
			 * core and init pieces aren't separated too
			 * far.  If this is ever broken, you will trip
			 * the check below.  The way to fix it would
			 * be to generate local stubs to go between init
			 * and core */
			if((Elf64_Sxword)(val - dot - 8) > 0x800000 -1 ||
			   (Elf64_Sxword)(val - dot - 8) < -0x800000) {
				printk(KERN_ERR "Module %s, symbol %s is out of range for PCREL22F relocation\n",
				       me->name, strtab + sym->st_name);
				return -ENOEXEC;
			}
			val = (val - dot - 8)/4;
			*loc = (*loc & ~0x3ff1ffd) | reassemble_22(val);
			break;
		case R_PARISC_DIR64:
			/* 64-bit effective address */
			*loc64 = val + addend;
			break;
		case R_PARISC_SEGREL32:
			/* 32-bit segment relative address */
			val -= (uint64_t)me->module_core;
			*loc = fsel(val, addend); 
			break;
		case R_PARISC_FPTR64:
			/* 64-bit function address */
			if(is_local(me, (void *)(val + addend))) {
				*loc64 = get_fdesc(me, val+addend);
				DEBUGP("FDESC for %s at %p points to %lx\n",
				       strtab + sym->st_name, *loc64,
				       ((Elf_Fdesc *)*loc64)->addr);
			} else {
				/* if the symbol is not local to this
				 * module then val+addend is a pointer
				 * to the function descriptor */
				DEBUGP("Non local FPTR64 Symbol %s loc %p val %lx\n",
				       strtab + sym->st_name,
				       loc, val);
				*loc64 = val + addend;
			}
			break;

		default:
			printk(KERN_ERR "module %s: Unknown relocation: %Lu\n",
			       me->name, ELF64_R_TYPE(rel[i].r_info));
			return -ENOEXEC;
		}
	}
	return 0;
}
#endif

int module_finalize(const Elf_Ehdr *hdr,
		    const Elf_Shdr *sechdrs,
		    struct module *me)
{
	int i;
	unsigned long nsyms;
	const char *strtab = NULL;
	Elf_Sym *newptr, *oldptr;
	Elf_Shdr *symhdr = NULL;
#ifdef DEBUG
	Elf_Fdesc *entry;
	u32 *addr;

	entry = (Elf_Fdesc *)me->init;
	printk("FINALIZE, ->init FPTR is %p, GP %lx ADDR %lx\n", entry,
	       entry->gp, entry->addr);
	addr = (u32 *)entry->addr;
	printk("INSNS: %x %x %x %x\n",
	       addr[0], addr[1], addr[2], addr[3]);
	printk("stubs used %ld, stubs max %ld\n"
	       "init_stubs used %ld, init stubs max %ld\n"
	       "got entries used %ld, gots max %ld\n"
	       "fdescs used %ld, fdescs max %ld\n",
	       me->arch.stub_count, me->arch.stub_max,
	       me->arch.init_stub_count, me->arch.init_stub_max,
	       me->arch.got_count, me->arch.got_max,
	       me->arch.fdesc_count, me->arch.fdesc_max);
#endif

	/* haven't filled in me->symtab yet, so have to find it
	 * ourselves */
	for (i = 1; i < hdr->e_shnum; i++) {
		if(sechdrs[i].sh_type == SHT_SYMTAB
		   && (sechdrs[i].sh_type & SHF_ALLOC)) {
			int strindex = sechdrs[i].sh_link;
			/* FIXME: AWFUL HACK
			 * The cast is to drop the const from
			 * the sechdrs pointer */
			symhdr = (Elf_Shdr *)&sechdrs[i];
			strtab = (char *)sechdrs[strindex].sh_addr;
			break;
		}
	}

	DEBUGP("module %s: strtab %p, symhdr %p\n",
	       me->name, strtab, symhdr);

	if(me->arch.got_count > MAX_GOTS) {
		printk(KERN_ERR "%s: Global Offset Table overflow (used %ld, allowed %d\n", me->name, me->arch.got_count, MAX_GOTS);
		return -EINVAL;
	}
	
	/* no symbol table */
	if(symhdr == NULL)
		return 0;

	oldptr = (void *)symhdr->sh_addr;
	newptr = oldptr + 1;	/* we start counting at 1 */
	nsyms = symhdr->sh_size / sizeof(Elf_Sym);
	DEBUGP("OLD num_symtab %lu\n", nsyms);

	for (i = 1; i < nsyms; i++) {
		oldptr++;	/* note, count starts at 1 so preincrement */
		if(strncmp(strtab + oldptr->st_name,
			      ".L", 2) == 0)
			continue;

		if(newptr != oldptr)
			*newptr++ = *oldptr;
		else
			newptr++;

	}
	nsyms = newptr - (Elf_Sym *)symhdr->sh_addr;
	DEBUGP("NEW num_symtab %lu\n", nsyms);
	symhdr->sh_size = nsyms * sizeof(Elf_Sym);
	return 0;
}

void module_arch_cleanup(struct module *mod)
{
}