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kernel-hacking-2024-linux-s.../arch/parisc/kernel/module.c
James Bottomley 6e1b9585aa [PARISC] Fix PCREL22F relocation problem for most modules 
The new problem, which has been affecting many more modules was that
our new ioremap really takes chunks out of our vmalloc space.  The net
result being that any two kernel vmalloc's now have to slot into the
chunked up space.  So the vmallocs for a modules init and core sectons
are no longer necessarily contiguous.  Unfortunately, the module loader
thinks that any internal symbol references should be satisfiable using the
jump instruction, which isn't true if the symbol is referenced from init
to core and vmalloc placed them a long way apart.

Fix this by introducing a new stub type for intra module inter sectional
jumps and using it.

Signed-off-by: James Bottomley <jejb@parisc-linux.org>
Signed-off-by: Kyle McMartin <kyle@parisc-linux.org>
2006-06-27 23:28:44 +00:00

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/* Kernel dynamically loadable module help for PARISC.
*
* The best reference for this stuff is probably the Processor-
* Specific ELF Supplement for PA-RISC:
* http://ftp.parisc-linux.org/docs/arch/elf-pa-hp.pdf
*
* Linux/PA-RISC Project (http://www.parisc-linux.org/)
* Copyright (C) 2003 Randolph Chung <tausq at debian . org>
*
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*
* Notes:
* - SEGREL32 handling
* We are not doing SEGREL32 handling correctly. According to the ABI, we
* should do a value offset, like this:
* if (is_init(me, (void *)val))
* val -= (uint32_t)me->module_init;
* else
* val -= (uint32_t)me->module_core;
* However, SEGREL32 is used only for PARISC unwind entries, and we want
* those entries to have an absolute address, and not just an offset.
*
* The unwind table mechanism has the ability to specify an offset for
* the unwind table; however, because we split off the init functions into
* a different piece of memory, it is not possible to do this using a
* single offset. Instead, we use the above hack for now.
*/
#include <linux/moduleloader.h>
#include <linux/elf.h>
#include <linux/vmalloc.h>
#include <linux/fs.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <asm/unwind.h>
#if 0
#define DEBUGP printk
#else
#define DEBUGP(fmt...)
#endif
#define CHECK_RELOC(val, bits) \
if ( ( !((val) & (1<<((bits)-1))) && ((val)>>(bits)) != 0 ) || \
( ((val) & (1<<((bits)-1))) && ((val)>>(bits)) != (((__typeof__(val))(~0))>>((bits)+2)))) { \
printk(KERN_ERR "module %s relocation of symbol %s is out of range (0x%lx in %d bits)\n", \
me->name, strtab + sym->st_name, (unsigned long)val, bits); \
return -ENOEXEC; \
}
/* Maximum number of GOT entries. We use a long displacement ldd from
* the bottom of the table, which has a maximum signed displacement of
* 0x3fff; however, since we're only going forward, this becomes
* 0x1fff, and thus, since each GOT entry is 8 bytes long we can have
* at most 1023 entries */
#define MAX_GOTS 1023
/* three functions to determine where in the module core
* or init pieces the location is */
static inline int is_init(struct module *me, void *loc)
{
return (loc >= me->module_init &&
loc <= (me->module_init + me->init_size));
}
static inline int is_core(struct module *me, void *loc)
{
return (loc >= me->module_core &&
loc <= (me->module_core + me->core_size));
}
static inline int is_local(struct module *me, void *loc)
{
return is_init(me, loc) || is_core(me, loc);
}
static inline int is_local_section(struct module *me, void *loc, void *dot)
{
return (is_init(me, loc) && is_init(me, dot)) ||
(is_core(me, loc) && is_core(me, dot));
}
#ifndef __LP64__
struct got_entry {
Elf32_Addr addr;
};
#define Elf_Fdesc Elf32_Fdesc
struct stub_entry {
Elf32_Word insns[2]; /* each stub entry has two insns */
};
#else
struct got_entry {
Elf64_Addr addr;
};
#define Elf_Fdesc Elf64_Fdesc
struct stub_entry {
Elf64_Word insns[4]; /* each stub entry has four insns */
};
#endif
/* Field selection types defined by hppa */
#define rnd(x) (((x)+0x1000)&~0x1fff)
/* fsel: full 32 bits */
#define fsel(v,a) ((v)+(a))
/* lsel: select left 21 bits */
#define lsel(v,a) (((v)+(a))>>11)
/* rsel: select right 11 bits */
#define rsel(v,a) (((v)+(a))&0x7ff)
/* lrsel with rounding of addend to nearest 8k */
#define lrsel(v,a) (((v)+rnd(a))>>11)
/* rrsel with rounding of addend to nearest 8k */
#define rrsel(v,a) ((((v)+rnd(a))&0x7ff)+((a)-rnd(a)))
#define mask(x,sz) ((x) & ~((1<<(sz))-1))
/* The reassemble_* functions prepare an immediate value for
insertion into an opcode. pa-risc uses all sorts of weird bitfields
in the instruction to hold the value. */
static inline int reassemble_14(int as14)
{
return (((as14 & 0x1fff) << 1) |
((as14 & 0x2000) >> 13));
}
static inline int reassemble_17(int as17)
{
return (((as17 & 0x10000) >> 16) |
((as17 & 0x0f800) << 5) |
((as17 & 0x00400) >> 8) |
((as17 & 0x003ff) << 3));
}
static inline int reassemble_21(int as21)
{
return (((as21 & 0x100000) >> 20) |
((as21 & 0x0ffe00) >> 8) |
((as21 & 0x000180) << 7) |
((as21 & 0x00007c) << 14) |
((as21 & 0x000003) << 12));
}
static inline int reassemble_22(int as22)
{
return (((as22 & 0x200000) >> 21) |
((as22 & 0x1f0000) << 5) |
((as22 & 0x00f800) << 5) |
((as22 & 0x000400) >> 8) |
((as22 & 0x0003ff) << 3));
}
void *module_alloc(unsigned long size)
{
if (size == 0)
return NULL;
return vmalloc(size);
}
#ifndef __LP64__
static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
{
return 0;
}
static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
{
return 0;
}
static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
{
unsigned long cnt = 0;
for (; n > 0; n--, rela++)
{
switch (ELF32_R_TYPE(rela->r_info)) {
case R_PARISC_PCREL17F:
case R_PARISC_PCREL22F:
cnt++;
}
}
return cnt;
}
#else
static inline unsigned long count_gots(const Elf_Rela *rela, unsigned long n)
{
unsigned long cnt = 0;
for (; n > 0; n--, rela++)
{
switch (ELF64_R_TYPE(rela->r_info)) {
case R_PARISC_LTOFF21L:
case R_PARISC_LTOFF14R:
case R_PARISC_PCREL22F:
cnt++;
}
}
return cnt;
}
static inline unsigned long count_fdescs(const Elf_Rela *rela, unsigned long n)
{
unsigned long cnt = 0;
for (; n > 0; n--, rela++)
{
switch (ELF64_R_TYPE(rela->r_info)) {
case R_PARISC_FPTR64:
cnt++;
}
}
return cnt;
}
static inline unsigned long count_stubs(const Elf_Rela *rela, unsigned long n)
{
unsigned long cnt = 0;
for (; n > 0; n--, rela++)
{
switch (ELF64_R_TYPE(rela->r_info)) {
case R_PARISC_PCREL22F:
cnt++;
}
}
return cnt;
}
#endif
/* Free memory returned from module_alloc */
void module_free(struct module *mod, void *module_region)
{
vfree(module_region);
/* FIXME: If module_region == mod->init_region, trim exception
table entries. */
}
#define CONST
int module_frob_arch_sections(CONST Elf_Ehdr *hdr,
CONST Elf_Shdr *sechdrs,
CONST char *secstrings,
struct module *me)
{
unsigned long gots = 0, fdescs = 0, stubs = 0, init_stubs = 0;
unsigned int i;
for (i = 1; i < hdr->e_shnum; i++) {
const Elf_Rela *rels = (void *)hdr + sechdrs[i].sh_offset;
unsigned long nrels = sechdrs[i].sh_size / sizeof(*rels);
if (strncmp(secstrings + sechdrs[i].sh_name,
".PARISC.unwind", 14) == 0)
me->arch.unwind_section = i;
if (sechdrs[i].sh_type != SHT_RELA)
continue;
/* some of these are not relevant for 32-bit/64-bit
* we leave them here to make the code common. the
* compiler will do its thing and optimize out the
* stuff we don't need
*/
gots += count_gots(rels, nrels);
fdescs += count_fdescs(rels, nrels);
if(strncmp(secstrings + sechdrs[i].sh_name,
".rela.init", 10) == 0)
init_stubs += count_stubs(rels, nrels);
else
stubs += count_stubs(rels, nrels);
}
/* align things a bit */
me->core_size = ALIGN(me->core_size, 16);
me->arch.got_offset = me->core_size;
me->core_size += gots * sizeof(struct got_entry);
me->core_size = ALIGN(me->core_size, 16);
me->arch.fdesc_offset = me->core_size;
me->core_size += fdescs * sizeof(Elf_Fdesc);
me->core_size = ALIGN(me->core_size, 16);
me->arch.stub_offset = me->core_size;
me->core_size += stubs * sizeof(struct stub_entry);
me->init_size = ALIGN(me->init_size, 16);
me->arch.init_stub_offset = me->init_size;
me->init_size += init_stubs * sizeof(struct stub_entry);
me->arch.got_max = gots;
me->arch.fdesc_max = fdescs;
me->arch.stub_max = stubs;
me->arch.init_stub_max = init_stubs;
return 0;
}
#ifdef __LP64__
static Elf64_Word get_got(struct module *me, unsigned long value, long addend)
{
unsigned int i;
struct got_entry *got;
value += addend;
BUG_ON(value == 0);
got = me->module_core + me->arch.got_offset;
for (i = 0; got[i].addr; i++)
if (got[i].addr == value)
goto out;
BUG_ON(++me->arch.got_count > me->arch.got_max);
got[i].addr = value;
out:
DEBUGP("GOT ENTRY %d[%x] val %lx\n", i, i*sizeof(struct got_entry),
value);
return i * sizeof(struct got_entry);
}
#endif /* __LP64__ */
#ifdef __LP64__
static Elf_Addr get_fdesc(struct module *me, unsigned long value)
{
Elf_Fdesc *fdesc = me->module_core + me->arch.fdesc_offset;
if (!value) {
printk(KERN_ERR "%s: zero OPD requested!\n", me->name);
return 0;
}
/* Look for existing fdesc entry. */
while (fdesc->addr) {
if (fdesc->addr == value)
return (Elf_Addr)fdesc;
fdesc++;
}
BUG_ON(++me->arch.fdesc_count > me->arch.fdesc_max);
/* Create new one */
fdesc->addr = value;
fdesc->gp = (Elf_Addr)me->module_core + me->arch.got_offset;
return (Elf_Addr)fdesc;
}
#endif /* __LP64__ */
enum elf_stub_type {
ELF_STUB_GOT,
ELF_STUB_MILLI,
ELF_STUB_DIRECT,
};
static Elf_Addr get_stub(struct module *me, unsigned long value, long addend,
enum elf_stub_type stub_type, int init_section)
{
unsigned long i;
struct stub_entry *stub;
if(init_section) {
i = me->arch.init_stub_count++;
BUG_ON(me->arch.init_stub_count > me->arch.init_stub_max);
stub = me->module_init + me->arch.init_stub_offset +
i * sizeof(struct stub_entry);
} else {
i = me->arch.stub_count++;
BUG_ON(me->arch.stub_count > me->arch.stub_max);
stub = me->module_core + me->arch.stub_offset +
i * sizeof(struct stub_entry);
}
#ifndef __LP64__
/* for 32-bit the stub looks like this:
* ldil L'XXX,%r1
* be,n R'XXX(%sr4,%r1)
*/
//value = *(unsigned long *)((value + addend) & ~3); /* why? */
stub->insns[0] = 0x20200000; /* ldil L'XXX,%r1 */
stub->insns[1] = 0xe0202002; /* be,n R'XXX(%sr4,%r1) */
stub->insns[0] |= reassemble_21(lrsel(value, addend));
stub->insns[1] |= reassemble_17(rrsel(value, addend) / 4);
#else
/* for 64-bit we have three kinds of stubs:
* for normal function calls:
* ldd 0(%dp),%dp
* ldd 10(%dp), %r1
* bve (%r1)
* ldd 18(%dp), %dp
*
* for millicode:
* ldil 0, %r1
* ldo 0(%r1), %r1
* ldd 10(%r1), %r1
* bve,n (%r1)
*
* for direct branches (jumps between different section of the
* same module):
* ldil 0, %r1
* ldo 0(%r1), %r1
* bve,n (%r1)
*/
switch (stub_type) {
case ELF_STUB_GOT:
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);
break;
case ELF_STUB_MILLI:
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));
break;
case ELF_STUB_DIRECT:
stub->insns[0] = 0x20200000; /* ldil 0,%r1 */
stub->insns[1] = 0x34210000; /* ldo 0(%r1), %r1 */
stub->insns[2] = 0xe820d002; /* bve,n (%r1) */
stub->insns[0] |= reassemble_21(lrsel(value, addend));
stub->insns[1] |= reassemble_14(rrsel(value, addend));
break;
}
#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 */
/* See note about special handling of SEGREL32 at
* the beginning of this file.
*/
*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, ELF_STUB_GOT, 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, ELF_STUB_GOT, 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_section(me, (void *)val, (void *)dot)) {
if (is_local(me, (void *)val))
/* this is the case where the
* symbol is local to the
* module, but in a different
* section, so stub the jump
* in case it's more than 22
* bits away */
val = get_stub(me, val, addend, ELF_STUB_DIRECT,
is_init(me, loc));
else if (strncmp(strtab + sym->st_name, "$$", 2)
== 0)
val = get_stub(me, val, addend, ELF_STUB_MILLI,
is_init(me, loc));
else
val = get_stub(me, val, addend, ELF_STUB_GOT,
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 */
/* See note about special handling of SEGREL32 at
* the beginning of this file.
*/
*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
static void
register_unwind_table(struct module *me,
const Elf_Shdr *sechdrs)
{
unsigned char *table, *end;
unsigned long gp;
if (!me->arch.unwind_section)
return;
table = (unsigned char *)sechdrs[me->arch.unwind_section].sh_addr;
end = table + sechdrs[me->arch.unwind_section].sh_size;
gp = (Elf_Addr)me->module_core + me->arch.got_offset;
DEBUGP("register_unwind_table(), sect = %d at 0x%p - 0x%p (gp=0x%lx)\n",
me->arch.unwind_section, table, end, gp);
me->arch.unwind = unwind_table_add(me->name, 0, gp, table, end);
}
static void
deregister_unwind_table(struct module *me)
{
if (me->arch.unwind)
unwind_table_remove(me->arch.unwind);
}
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
register_unwind_table(me, sechdrs);
/* 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)
{
deregister_unwind_table(mod);
}
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