[BusyBox] [PATCH] Busybox insmod and powerpc
Magnus Damm
damm at opensource.se
Tue Feb 20 18:48:25 UTC 2001
Hi all,
Now is insmod happily running on my embedded powerpc target.
The patch is against busybox-0.49.
I did some cleanup which is affecting all platforms...
Feedback, please!
Cheers /
Magnus
(Please CC me - I'm not on the list)
-------------- next part --------------
--- busybox-0.49/insmod.c Sat Jan 27 10:37:00 2001
+++ bb/insmod.c Tue Feb 20 19:39:54 2001
@@ -14,6 +14,12 @@
* very minor changes required to also work with StrongArm and presumably
* all ARM based systems.
*
+ * Magnus Damm <damm at opensource.se> added PowerPC support 20-Feb-2001.
+ * PowerPC specific code stolen from modutils-2.3.16,
+ * written by Paul Mackerras, Copyright 1996, 1997 Linux International.
+ * I've only tested the code on mpc8xx platforms in big-endian mode.
+ * Did some cleanup and added BB_USE_xxx_ENTRIES...
+ *
* Based almost entirely on the Linux modutils-2.3.11 implementation.
* Copyright 1996, 1997 Linux International.
* New implementation contributed by Richard Henderson <rth at tamu.edu>
@@ -52,6 +58,28 @@
#include <sys/syscall.h>
#include <linux/unistd.h>
+#if defined(__powerpc__)
+#define BB_USE_PLT_ENTRIES
+#define BB_PLT_ENTRY_SIZE 16
+#endif
+
+#if defined(__arm__)
+#define BB_USE_PLT_ENTRIES
+#define BB_PLT_ENTRY_SIZE 8
+#define BB_USE_GOT_ENTRIES
+#define BB_GOT_ENTRY_SIZE 8
+#endif
+
+#if defined(__sh__)
+#define BB_USE_GOT_ENTRIES
+#define BB_GOT_ENTRY_SIZE 4
+#endif
+
+#if defined(__i386__)
+#define BB_USE_GOT_ENTRIES
+#define BB_GOT_ENTRY_SIZE 4
+#endif
+
//----------------------------------------------------------------------------
//--------modutils module.h, lines 45-242
//----------------------------------------------------------------------------
@@ -311,21 +339,27 @@
#endif
#define ELFCLASSM ELFCLASS32
-#define ELFDATAM ELFDATA2LSB
-
-
#if defined(__sh__)
#define MATCH_MACHINE(x) (x == EM_SH)
#define SHT_RELM SHT_RELA
#define Elf32_RelM Elf32_Rela
+#define ELFDATAM ELFDATA2LSB
#elif defined(__arm__)
#define MATCH_MACHINE(x) (x == EM_ARM)
#define SHT_RELM SHT_REL
#define Elf32_RelM Elf32_Rel
+#define ELFDATAM ELFDATA2LSB
+
+#elif defined(__powerpc__)
+
+#define MATCH_MACHINE(x) (x == EM_PPC)
+#define SHT_RELM SHT_RELA
+#define Elf32_RelM Elf32_Rela
+#define ELFDATAM ELFDATA2MSB
#elif defined(__i386__)
@@ -340,6 +374,7 @@
#define SHT_RELM SHT_REL
#define Elf32_RelM Elf32_Rel
+#define ELFDATAM ELFDATA2LSB
#else
#error Sorry, but insmod.c does not yet support this architecture...
@@ -540,8 +575,10 @@
/* Done ;-) */
-#if defined(__arm__)
-struct arm_plt_entry
+
+
+#if defined(BB_USE_PLT_ENTRIES)
+struct arch_plt_entry
{
int offset;
int allocated:1;
@@ -549,26 +586,32 @@
};
#endif
+#if defined(BB_USE_GOT_ENTRIES)
struct arch_got_entry {
int offset;
unsigned offset_done:1;
unsigned reloc_done:1;
};
+#endif
struct arch_file {
struct obj_file root;
-#if defined(__arm__)
- struct obj_section *plt;
+#if defined(BB_USE_PLT_ENTRIES)
+ struct obj_section *plt;
#endif
+#if defined(BB_USE_GOT_ENTRIES)
struct obj_section *got;
+#endif
};
struct arch_symbol {
struct obj_symbol root;
-#if defined(__arm__)
- struct arm_plt_entry pltent;
+#if defined(BB_USE_PLT_ENTRIES)
+ struct arch_plt_entry pltent;
#endif
+#if defined(BB_USE_GOT_ENTRIES)
struct arch_got_entry gotent;
+#endif
};
@@ -618,7 +661,8 @@
_syscall1(int, get_kernel_syms, struct old_kernel_sym *, ks)
#endif
-#if defined(__i386__) || defined(__m68k__) || defined(__arm__)
+#if defined(__i386__) || defined(__m68k__) || defined(__arm__) \
+ || defined(__powerpc__)
/* Jump through hoops to fixup error return codes */
#define __NR__create_module __NR_create_module
static inline _syscall2(long, _create_module, const char *, name, size_t,
@@ -673,7 +717,14 @@
{
struct arch_file *f;
f = xmalloc(sizeof(*f));
+
+#if defined(BB_USE_PLT_ENTRIES)
+ f->plt = NULL;
+#endif
+#if defined(BB_USE_GOT_ENTRIES)
f->got = NULL;
+#endif
+
return &f->root;
}
@@ -686,7 +737,14 @@
{
struct arch_symbol *sym;
sym = xmalloc(sizeof(*sym));
+
+#if defined(BB_USE_PLT_ENTRIES)
+ memset(&sym->pltent, 0, sizeof(sym->pltent));
+#endif
+#if defined(BB_USE_GOT_ENTRIES)
memset(&sym->gotent, 0, sizeof(sym->gotent));
+#endif
+
return &sym->root;
}
@@ -702,14 +760,14 @@
ElfW(Addr) *loc = (ElfW(Addr) *) (targsec->contents + rel->r_offset);
ElfW(Addr) dot = targsec->header.sh_addr + rel->r_offset;
+#if defined(BB_USE_GOT_ENTRIES)
ElfW(Addr) got = ifile->got ? ifile->got->header.sh_addr : 0;
-#if defined(__arm__)
+#endif
+#if defined(BB_USE_PLT_ENTRIES)
ElfW(Addr) plt = ifile->plt ? ifile->plt->header.sh_addr : 0;
-
- struct arm_plt_entry *pe;
+ struct arch_plt_entry *pe;
unsigned long *ip;
#endif
-
enum obj_reloc ret = obj_reloc_ok;
switch (ELF32_R_TYPE(rel->r_info)) {
@@ -723,6 +781,8 @@
case R_ARM_NONE:
#elif defined(__i386__)
case R_386_NONE:
+#elif defined(__powerpc__)
+ case R_PPC_NONE:
#endif
break;
@@ -731,11 +791,27 @@
#elif defined(__arm__)
case R_ARM_ABS32:
#elif defined(__i386__)
- case R_386_32:
+ case R_386_32:
+#elif defined(__powerpc__)
+ case R_PPC_ADDR32:
#endif
*loc += v;
break;
+#if defined(__powerpc__)
+ case R_PPC_ADDR16_HA:
+ *(unsigned short *)loc = (v + 0x8000) >> 16;
+ break;
+
+ case R_PPC_ADDR16_HI:
+ *(unsigned short *)loc = v >> 16;
+ break;
+
+ case R_PPC_ADDR16_LO:
+ *(unsigned short *)loc = v;
+ break;
+#endif
+
#if defined(__arm__)
#elif defined(__sh__)
case R_SH_REL32:
@@ -746,22 +822,48 @@
case R_386_PC32:
*loc += v - dot;
break;
+#elif defined(__powerpc__)
+ case R_PPC_REL32:
+ *loc = v - dot;
+ break;
#endif
#if defined(__sh__)
case R_SH_PLT32:
*loc = v - dot;
break;
-#elif defined(__arm__)
+#elif defined(__i386__)
+#endif
+
+#if defined(BB_USE_PLT_ENTRIES)
+
+#if defined(__arm__)
case R_ARM_PC24:
case R_ARM_PLT32:
+#endif
+#if defined(__powerpc__)
+ case R_PPC_REL24:
+#endif
/* find the plt entry and initialize it if necessary */
assert(isym != NULL);
- pe = (struct arm_plt_entry*) &isym->pltent;
+
+ pe = (struct arch_plt_entry*) &isym->pltent;
+
if (! pe->inited) {
ip = (unsigned long *) (ifile->plt->contents + pe->offset);
+
+ /* generate some machine code */
+
+#if defined(__arm__)
ip[0] = 0xe51ff004; /* ldr pc,[pc,#-4] */
ip[1] = v; /* sym@ */
+#endif
+#if defined(__powerpc__)
+ ip[0] = 0x3d600000 + ((v + 0x8000) >> 16); /* lis r11,sym at ha */
+ ip[1] = 0x396b0000 + (v & 0xffff); /* addi r11,r11,sym at l */
+ ip[2] = 0x7d6903a6; /* mtctr r11 */
+ ip[3] = 0x4e800420; /* bctr */
+#endif
pe->inited = 1;
}
@@ -775,15 +877,18 @@
if (v & 3)
ret = obj_reloc_dangerous;
+ /* merge the offset into the instruction. */
+#if defined(__arm__)
/* Convert to words. */
v >>= 2;
- /* merge the offset into the instruction. */
*loc = (*loc & ~0x00ffffff) | ((v + *loc) & 0x00ffffff);
- break;
-#elif defined(__i386__)
#endif
-
+#if defined(__powerpc__)
+ *loc = (*loc & ~0x03fffffc) | (v & 0x03fffffc);
+#endif
+ break;
+#endif /* BB_USE_PLT_ENTRIES */
#if defined(__arm__)
#elif defined(__sh__)
@@ -809,6 +914,8 @@
break;
#endif
+#if defined(BB_USE_GOT_ENTRIES)
+
#if defined(__sh__)
case R_SH_GOTPC:
#elif defined(__arm__)
@@ -827,7 +934,7 @@
#if defined(__sh__)
case R_SH_GOT32:
#elif defined(__arm__)
- case R_ARM_GOT32:
+ case R_ARM_GOT32:
#elif defined(__i386__)
case R_386_GOT32:
#endif
@@ -849,7 +956,7 @@
#if defined(__sh__)
case R_SH_GOTOFF:
#elif defined(__arm__)
- case R_ARM_GOTOFF:
+ case R_ARM_GOTOFF:
#elif defined(__i386__)
case R_386_GOTOFF:
#endif
@@ -857,6 +964,8 @@
*loc += v - got;
break;
+#endif /* BB_USE_GOT_ENTRIES */
+
default:
printf("Warning: unhandled reloc %d\n",(int)ELF32_R_TYPE(rel->r_info));
ret = obj_reloc_unhandled;
@@ -869,8 +978,11 @@
int arch_create_got(struct obj_file *f)
{
struct arch_file *ifile = (struct arch_file *) f;
- int i, got_offset = 0, gotneeded = 0;
-#if defined(__arm__)
+ int i;
+#if defined(BB_USE_GOT_ENTRIES)
+ int got_offset = 0, gotneeded = 0;
+#endif
+#if defined(BB_USE_PLT_ENTRIES)
int plt_offset = 0, pltneeded = 0;
#endif
struct obj_section *relsec, *symsec, *strsec;
@@ -898,12 +1010,20 @@
switch (ELF32_R_TYPE(rel->r_info)) {
#if defined(__arm__)
case R_ARM_GOT32:
+ break;
#elif defined(__sh__)
case R_SH_GOT32:
+ break;
#elif defined(__i386__)
case R_386_GOT32:
+ break;
#endif
+
+#if defined(__powerpc__)
+ case R_PPC_REL24:
+ pltneeded = 1;
break;
+#endif
#if defined(__arm__)
case R_ARM_PC24:
@@ -936,17 +1056,18 @@
name = f->sections[extsym->st_shndx]->name;
}
intsym = (struct arch_symbol *) obj_find_symbol(f, name);
-
+#if defined(BB_USE_GOT_ENTRIES)
if (!intsym->gotent.offset_done) {
intsym->gotent.offset_done = 1;
intsym->gotent.offset = got_offset;
- got_offset += 4;
+ got_offset += BB_GOT_ENTRY_SIZE;
}
-#if defined(__arm__)
+#endif
+#if defined(BB_USE_PLT_ENTRIES)
if (pltneeded && intsym->pltent.allocated == 0) {
intsym->pltent.allocated = 1;
intsym->pltent.offset = plt_offset;
- plt_offset += 8;
+ plt_offset += BB_PLT_ENTRY_SIZE;
intsym->pltent.inited = 0;
pltneeded = 0;
}
@@ -954,27 +1075,29 @@
}
}
-#if defined(__arm__)
+#if defined(BB_USE_GOT_ENTRIES)
if (got_offset) {
struct obj_section* relsec = obj_find_section(f, ".got");
if (relsec) {
obj_extend_section(relsec, got_offset);
} else {
- relsec = obj_create_alloced_section(f, ".got", 8, got_offset);
+ relsec = obj_create_alloced_section(f, ".got",
+ BB_GOT_ENTRY_SIZE,
+ got_offset);
assert(relsec);
}
ifile->got = relsec;
}
+#endif
+#if defined(BB_USE_PLT_ENTRIES)
if (plt_offset)
- ifile->plt = obj_create_alloced_section(f, ".plt", 8, plt_offset);
-#else
- if (got_offset > 0 || gotneeded)
- ifile->got = obj_create_alloced_section(f, ".got", 4, got_offset);
+ ifile->plt = obj_create_alloced_section(f, ".plt",
+ BB_PLT_ENTRY_SIZE,
+ plt_offset);
#endif
-
return 1;
}
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